Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

28 files changed, 14244 insertions, 0 deletions

diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
new file mode 100644
index 000000000..3eef72ce9
--- /dev/null
+++ b/net/dsa/Kconfig
@@ -0,0 +1,169 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+menuconfig NET_DSA
+	tristate "Distributed Switch Architecture"
+	depends on BRIDGE || BRIDGE=n
+	depends on HSR || HSR=n
+	depends on INET && NETDEVICES
+	select GRO_CELLS
+	select NET_SWITCHDEV
+	select PHYLINK
+	select NET_DEVLINK
+	imply NET_SELFTESTS
+	help
+	  Say Y if you want to enable support for the hardware switches supported
+	  by the Distributed Switch Architecture.
+
+if NET_DSA
+
+# Drivers must select the appropriate tagging format(s)
+
+config NET_DSA_TAG_AR9331
+	tristate "Tag driver for Atheros AR9331 SoC with built-in switch"
+	help
+	  Say Y or M if you want to enable support for tagging frames for
+	  the Atheros AR9331 SoC with built-in switch.
+
+config NET_DSA_TAG_BRCM_COMMON
+	tristate
+	default n
+
+config NET_DSA_TAG_BRCM
+	tristate "Tag driver for Broadcom switches using in-frame headers"
+	select NET_DSA_TAG_BRCM_COMMON
+	help
+	  Say Y if you want to enable support for tagging frames for the
+	  Broadcom switches which place the tag after the MAC source address.
+
+config NET_DSA_TAG_BRCM_LEGACY
+	tristate "Tag driver for Broadcom legacy switches using in-frame headers"
+	select NET_DSA_TAG_BRCM_COMMON
+	help
+	  Say Y if you want to enable support for tagging frames for the
+	  Broadcom legacy switches which place the tag after the MAC source
+	  address.
+
+config NET_DSA_TAG_BRCM_PREPEND
+	tristate "Tag driver for Broadcom switches using prepended headers"
+	select NET_DSA_TAG_BRCM_COMMON
+	help
+	  Say Y if you want to enable support for tagging frames for the
+	  Broadcom switches which places the tag before the Ethernet header
+	  (prepended).
+
+config NET_DSA_TAG_HELLCREEK
+	tristate "Tag driver for Hirschmann Hellcreek TSN switches"
+	help
+	  Say Y or M if you want to enable support for tagging frames
+	  for the Hirschmann Hellcreek TSN switches.
+
+config NET_DSA_TAG_GSWIP
+	tristate "Tag driver for Lantiq / Intel GSWIP switches"
+	help
+	  Say Y or M if you want to enable support for tagging frames for the
+	  Lantiq / Intel GSWIP switches.
+
+config NET_DSA_TAG_DSA_COMMON
+	tristate
+
+config NET_DSA_TAG_DSA
+	tristate "Tag driver for Marvell switches using DSA headers"
+	select NET_DSA_TAG_DSA_COMMON
+	help
+	  Say Y or M if you want to enable support for tagging frames for the
+	  Marvell switches which use DSA headers.
+
+config NET_DSA_TAG_EDSA
+	tristate "Tag driver for Marvell switches using EtherType DSA headers"
+	select NET_DSA_TAG_DSA_COMMON
+	help
+	  Say Y or M if you want to enable support for tagging frames for the
+	  Marvell switches which use EtherType DSA headers.
+
+config NET_DSA_TAG_MTK
+	tristate "Tag driver for Mediatek switches"
+	help
+	  Say Y or M if you want to enable support for tagging frames for
+	  Mediatek switches.
+
+config NET_DSA_TAG_KSZ
+	tristate "Tag driver for Microchip 8795/937x/9477/9893 families of switches"
+	help
+	  Say Y if you want to enable support for tagging frames for the
+	  Microchip 8795/937x/9477/9893 families of switches.
+
+config NET_DSA_TAG_OCELOT
+	tristate "Tag driver for Ocelot family of switches, using NPI port"
+	select PACKING
+	help
+	  Say Y or M if you want to enable NPI tagging for the Ocelot switches
+	  (VSC7511, VSC7512, VSC7513, VSC7514, VSC9953, VSC9959). In this mode,
+	  the frames over the Ethernet CPU port are prepended with a
+	  hardware-defined injection/extraction frame header.  Flow control
+	  (PAUSE frames) over the CPU port is not supported when operating in
+	  this mode.
+
+config NET_DSA_TAG_OCELOT_8021Q
+	tristate "Tag driver for Ocelot family of switches, using VLAN"
+	help
+	  Say Y or M if you want to enable support for tagging frames with a
+	  custom VLAN-based header. Frames that require timestamping, such as
+	  PTP, are not delivered over Ethernet but over register-based MMIO.
+	  Flow control over the CPU port is functional in this mode. When using
+	  this mode, less TCAM resources (VCAP IS1, IS2, ES0) are available for
+	  use with tc-flower.
+
+config NET_DSA_TAG_QCA
+	tristate "Tag driver for Qualcomm Atheros QCA8K switches"
+	help
+	  Say Y or M if you want to enable support for tagging frames for
+	  the Qualcomm Atheros QCA8K switches.
+
+config NET_DSA_TAG_RTL4_A
+	tristate "Tag driver for Realtek 4 byte protocol A tags"
+	help
+	  Say Y or M if you want to enable support for tagging frames for the
+	  Realtek switches with 4 byte protocol A tags, sich as found in
+	  the Realtek RTL8366RB.
+
+config NET_DSA_TAG_RTL8_4
+	tristate "Tag driver for Realtek 8 byte protocol 4 tags"
+	help
+	  Say Y or M if you want to enable support for tagging frames for Realtek
+	  switches with 8 byte protocol 4 tags, such as the Realtek RTL8365MB-VC.
+
+config NET_DSA_TAG_RZN1_A5PSW
+	tristate "Tag driver for Renesas RZ/N1 A5PSW switch"
+	help
+	  Say Y or M if you want to enable support for tagging frames for
+	  Renesas RZ/N1 embedded switch that uses an 8 byte tag located after
+	  destination MAC address.
+
+config NET_DSA_TAG_LAN9303
+	tristate "Tag driver for SMSC/Microchip LAN9303 family of switches"
+	help
+	  Say Y or M if you want to enable support for tagging frames for the
+	  SMSC/Microchip LAN9303 family of switches.
+
+config NET_DSA_TAG_SJA1105
+	tristate "Tag driver for NXP SJA1105 switches"
+	select PACKING
+	help
+	  Say Y or M if you want to enable support for tagging frames with the
+	  NXP SJA1105 switch family. Both the native tagging protocol (which
+	  is only for link-local traffic) as well as non-native tagging (based
+	  on a custom 802.1Q VLAN header) are available.
+
+config NET_DSA_TAG_TRAILER
+	tristate "Tag driver for switches using a trailer tag"
+	help
+	  Say Y or M if you want to enable support for tagging frames at
+	  with a trailed. e.g. Marvell 88E6060.
+
+config NET_DSA_TAG_XRS700X
+	tristate "Tag driver for XRS700x switches"
+	help
+	  Say Y or M if you want to enable support for tagging frames for
+	  Arrow SpeedChips XRS700x switches that use a single byte tag trailer.
+
+endif
diff --git a/net/dsa/Makefile b/net/dsa/Makefile
new file mode 100644
index 000000000..bf57ef3bc
--- /dev/null
+++ b/net/dsa/Makefile
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0
+# the core
+obj-$(CONFIG_NET_DSA) += dsa_core.o
+dsa_core-y += \
+	dsa.o \
+	dsa2.o \
+	master.o \
+	netlink.o \
+	port.o \
+	slave.o \
+	switch.o \
+	tag_8021q.o
+
+# tagging formats
+obj-$(CONFIG_NET_DSA_TAG_AR9331) += tag_ar9331.o
+obj-$(CONFIG_NET_DSA_TAG_BRCM_COMMON) += tag_brcm.o
+obj-$(CONFIG_NET_DSA_TAG_DSA_COMMON) += tag_dsa.o
+obj-$(CONFIG_NET_DSA_TAG_GSWIP) += tag_gswip.o
+obj-$(CONFIG_NET_DSA_TAG_HELLCREEK) += tag_hellcreek.o
+obj-$(CONFIG_NET_DSA_TAG_KSZ) += tag_ksz.o
+obj-$(CONFIG_NET_DSA_TAG_LAN9303) += tag_lan9303.o
+obj-$(CONFIG_NET_DSA_TAG_MTK) += tag_mtk.o
+obj-$(CONFIG_NET_DSA_TAG_OCELOT) += tag_ocelot.o
+obj-$(CONFIG_NET_DSA_TAG_OCELOT_8021Q) += tag_ocelot_8021q.o
+obj-$(CONFIG_NET_DSA_TAG_QCA) += tag_qca.o
+obj-$(CONFIG_NET_DSA_TAG_RTL4_A) += tag_rtl4_a.o
+obj-$(CONFIG_NET_DSA_TAG_RTL8_4) += tag_rtl8_4.o
+obj-$(CONFIG_NET_DSA_TAG_RZN1_A5PSW) += tag_rzn1_a5psw.o
+obj-$(CONFIG_NET_DSA_TAG_SJA1105) += tag_sja1105.o
+obj-$(CONFIG_NET_DSA_TAG_TRAILER) += tag_trailer.o
+obj-$(CONFIG_NET_DSA_TAG_XRS700X) += tag_xrs700x.o
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
new file mode 100644
index 000000000..64b14f655
--- /dev/null
+++ b/net/dsa/dsa.c
@@ -0,0 +1,570 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * net/dsa/dsa.c - Hardware switch handling
+ * Copyright (c) 2008-2009 Marvell Semiconductor
+ * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
+ */
+
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/sysfs.h>
+#include <linux/ptp_classify.h>
+
+#include "dsa_priv.h"
+
+static LIST_HEAD(dsa_tag_drivers_list);
+static DEFINE_MUTEX(dsa_tag_drivers_lock);
+
+static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
+					    struct net_device *dev)
+{
+	/* Just return the original SKB */
+	return skb;
+}
+
+static const struct dsa_device_ops none_ops = {
+	.name	= "none",
+	.proto	= DSA_TAG_PROTO_NONE,
+	.xmit	= dsa_slave_notag_xmit,
+	.rcv	= NULL,
+};
+
+DSA_TAG_DRIVER(none_ops);
+
+static void dsa_tag_driver_register(struct dsa_tag_driver *dsa_tag_driver,
+				    struct module *owner)
+{
+	dsa_tag_driver->owner = owner;
+
+	mutex_lock(&dsa_tag_drivers_lock);
+	list_add_tail(&dsa_tag_driver->list, &dsa_tag_drivers_list);
+	mutex_unlock(&dsa_tag_drivers_lock);
+}
+
+void dsa_tag_drivers_register(struct dsa_tag_driver *dsa_tag_driver_array[],
+			      unsigned int count, struct module *owner)
+{
+	unsigned int i;
+
+	for (i = 0; i < count; i++)
+		dsa_tag_driver_register(dsa_tag_driver_array[i], owner);
+}
+
+static void dsa_tag_driver_unregister(struct dsa_tag_driver *dsa_tag_driver)
+{
+	mutex_lock(&dsa_tag_drivers_lock);
+	list_del(&dsa_tag_driver->list);
+	mutex_unlock(&dsa_tag_drivers_lock);
+}
+EXPORT_SYMBOL_GPL(dsa_tag_drivers_register);
+
+void dsa_tag_drivers_unregister(struct dsa_tag_driver *dsa_tag_driver_array[],
+				unsigned int count)
+{
+	unsigned int i;
+
+	for (i = 0; i < count; i++)
+		dsa_tag_driver_unregister(dsa_tag_driver_array[i]);
+}
+EXPORT_SYMBOL_GPL(dsa_tag_drivers_unregister);
+
+const char *dsa_tag_protocol_to_str(const struct dsa_device_ops *ops)
+{
+	return ops->name;
+};
+
+/* Function takes a reference on the module owning the tagger,
+ * so dsa_tag_driver_put must be called afterwards.
+ */
+const struct dsa_device_ops *dsa_find_tagger_by_name(const char *buf)
+{
+	const struct dsa_device_ops *ops = ERR_PTR(-ENOPROTOOPT);
+	struct dsa_tag_driver *dsa_tag_driver;
+
+	mutex_lock(&dsa_tag_drivers_lock);
+	list_for_each_entry(dsa_tag_driver, &dsa_tag_drivers_list, list) {
+		const struct dsa_device_ops *tmp = dsa_tag_driver->ops;
+
+		if (!sysfs_streq(buf, tmp->name))
+			continue;
+
+		if (!try_module_get(dsa_tag_driver->owner))
+			break;
+
+		ops = tmp;
+		break;
+	}
+	mutex_unlock(&dsa_tag_drivers_lock);
+
+	return ops;
+}
+
+const struct dsa_device_ops *dsa_tag_driver_get(int tag_protocol)
+{
+	struct dsa_tag_driver *dsa_tag_driver;
+	const struct dsa_device_ops *ops;
+	bool found = false;
+
+	request_module("%s%d", DSA_TAG_DRIVER_ALIAS, tag_protocol);
+
+	mutex_lock(&dsa_tag_drivers_lock);
+	list_for_each_entry(dsa_tag_driver, &dsa_tag_drivers_list, list) {
+		ops = dsa_tag_driver->ops;
+		if (ops->proto == tag_protocol) {
+			found = true;
+			break;
+		}
+	}
+
+	if (found) {
+		if (!try_module_get(dsa_tag_driver->owner))
+			ops = ERR_PTR(-ENOPROTOOPT);
+	} else {
+		ops = ERR_PTR(-ENOPROTOOPT);
+	}
+
+	mutex_unlock(&dsa_tag_drivers_lock);
+
+	return ops;
+}
+
+void dsa_tag_driver_put(const struct dsa_device_ops *ops)
+{
+	struct dsa_tag_driver *dsa_tag_driver;
+
+	mutex_lock(&dsa_tag_drivers_lock);
+	list_for_each_entry(dsa_tag_driver, &dsa_tag_drivers_list, list) {
+		if (dsa_tag_driver->ops == ops) {
+			module_put(dsa_tag_driver->owner);
+			break;
+		}
+	}
+	mutex_unlock(&dsa_tag_drivers_lock);
+}
+
+static int dev_is_class(struct device *dev, void *class)
+{
+	if (dev->class != NULL && !strcmp(dev->class->name, class))
+		return 1;
+
+	return 0;
+}
+
+static struct device *dev_find_class(struct device *parent, char *class)
+{
+	if (dev_is_class(parent, class)) {
+		get_device(parent);
+		return parent;
+	}
+
+	return device_find_child(parent, class, dev_is_class);
+}
+
+struct net_device *dsa_dev_to_net_device(struct device *dev)
+{
+	struct device *d;
+
+	d = dev_find_class(dev, "net");
+	if (d != NULL) {
+		struct net_device *nd;
+
+		nd = to_net_dev(d);
+		dev_hold(nd);
+		put_device(d);
+
+		return nd;
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(dsa_dev_to_net_device);
+
+/* Determine if we should defer delivery of skb until we have a rx timestamp.
+ *
+ * Called from dsa_switch_rcv. For now, this will only work if tagging is
+ * enabled on the switch. Normally the MAC driver would retrieve the hardware
+ * timestamp when it reads the packet out of the hardware. However in a DSA
+ * switch, the DSA driver owning the interface to which the packet is
+ * delivered is never notified unless we do so here.
+ */
+static bool dsa_skb_defer_rx_timestamp(struct dsa_slave_priv *p,
+				       struct sk_buff *skb)
+{
+	struct dsa_switch *ds = p->dp->ds;
+	unsigned int type;
+
+	if (skb_headroom(skb) < ETH_HLEN)
+		return false;
+
+	__skb_push(skb, ETH_HLEN);
+
+	type = ptp_classify_raw(skb);
+
+	__skb_pull(skb, ETH_HLEN);
+
+	if (type == PTP_CLASS_NONE)
+		return false;
+
+	if (likely(ds->ops->port_rxtstamp))
+		return ds->ops->port_rxtstamp(ds, p->dp->index, skb, type);
+
+	return false;
+}
+
+static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
+			  struct packet_type *pt, struct net_device *unused)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	struct sk_buff *nskb = NULL;
+	struct dsa_slave_priv *p;
+
+	if (unlikely(!cpu_dp)) {
+		kfree_skb(skb);
+		return 0;
+	}
+
+	skb = skb_unshare(skb, GFP_ATOMIC);
+	if (!skb)
+		return 0;
+
+	nskb = cpu_dp->rcv(skb, dev);
+	if (!nskb) {
+		kfree_skb(skb);
+		return 0;
+	}
+
+	skb = nskb;
+	skb_push(skb, ETH_HLEN);
+	skb->pkt_type = PACKET_HOST;
+	skb->protocol = eth_type_trans(skb, skb->dev);
+
+	if (unlikely(!dsa_slave_dev_check(skb->dev))) {
+		/* Packet is to be injected directly on an upper
+		 * device, e.g. a team/bond, so skip all DSA-port
+		 * specific actions.
+		 */
+		netif_rx(skb);
+		return 0;
+	}
+
+	p = netdev_priv(skb->dev);
+
+	if (unlikely(cpu_dp->ds->untag_bridge_pvid)) {
+		nskb = dsa_untag_bridge_pvid(skb);
+		if (!nskb) {
+			kfree_skb(skb);
+			return 0;
+		}
+		skb = nskb;
+	}
+
+	dev_sw_netstats_rx_add(skb->dev, skb->len);
+
+	if (dsa_skb_defer_rx_timestamp(p, skb))
+		return 0;
+
+	gro_cells_receive(&p->gcells, skb);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static bool dsa_port_is_initialized(const struct dsa_port *dp)
+{
+	return dp->type == DSA_PORT_TYPE_USER && dp->slave;
+}
+
+int dsa_switch_suspend(struct dsa_switch *ds)
+{
+	struct dsa_port *dp;
+	int ret = 0;
+
+	/* Suspend slave network devices */
+	dsa_switch_for_each_port(dp, ds) {
+		if (!dsa_port_is_initialized(dp))
+			continue;
+
+		ret = dsa_slave_suspend(dp->slave);
+		if (ret)
+			return ret;
+	}
+
+	if (ds->ops->suspend)
+		ret = ds->ops->suspend(ds);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dsa_switch_suspend);
+
+int dsa_switch_resume(struct dsa_switch *ds)
+{
+	struct dsa_port *dp;
+	int ret = 0;
+
+	if (ds->ops->resume)
+		ret = ds->ops->resume(ds);
+
+	if (ret)
+		return ret;
+
+	/* Resume slave network devices */
+	dsa_switch_for_each_port(dp, ds) {
+		if (!dsa_port_is_initialized(dp))
+			continue;
+
+		ret = dsa_slave_resume(dp->slave);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dsa_switch_resume);
+#endif
+
+static struct packet_type dsa_pack_type __read_mostly = {
+	.type	= cpu_to_be16(ETH_P_XDSA),
+	.func	= dsa_switch_rcv,
+};
+
+static struct workqueue_struct *dsa_owq;
+
+bool dsa_schedule_work(struct work_struct *work)
+{
+	return queue_work(dsa_owq, work);
+}
+
+void dsa_flush_workqueue(void)
+{
+	flush_workqueue(dsa_owq);
+}
+EXPORT_SYMBOL_GPL(dsa_flush_workqueue);
+
+int dsa_devlink_param_get(struct devlink *dl, u32 id,
+			  struct devlink_param_gset_ctx *ctx)
+{
+	struct dsa_switch *ds = dsa_devlink_to_ds(dl);
+
+	if (!ds->ops->devlink_param_get)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_param_get(ds, id, ctx);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_param_get);
+
+int dsa_devlink_param_set(struct devlink *dl, u32 id,
+			  struct devlink_param_gset_ctx *ctx)
+{
+	struct dsa_switch *ds = dsa_devlink_to_ds(dl);
+
+	if (!ds->ops->devlink_param_set)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_param_set(ds, id, ctx);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_param_set);
+
+int dsa_devlink_params_register(struct dsa_switch *ds,
+				const struct devlink_param *params,
+				size_t params_count)
+{
+	return devlink_params_register(ds->devlink, params, params_count);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_params_register);
+
+void dsa_devlink_params_unregister(struct dsa_switch *ds,
+				   const struct devlink_param *params,
+				   size_t params_count)
+{
+	devlink_params_unregister(ds->devlink, params, params_count);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_params_unregister);
+
+int dsa_devlink_resource_register(struct dsa_switch *ds,
+				  const char *resource_name,
+				  u64 resource_size,
+				  u64 resource_id,
+				  u64 parent_resource_id,
+				  const struct devlink_resource_size_params *size_params)
+{
+	return devlink_resource_register(ds->devlink, resource_name,
+					 resource_size, resource_id,
+					 parent_resource_id,
+					 size_params);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_resource_register);
+
+void dsa_devlink_resources_unregister(struct dsa_switch *ds)
+{
+	devlink_resources_unregister(ds->devlink);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_resources_unregister);
+
+void dsa_devlink_resource_occ_get_register(struct dsa_switch *ds,
+					   u64 resource_id,
+					   devlink_resource_occ_get_t *occ_get,
+					   void *occ_get_priv)
+{
+	return devlink_resource_occ_get_register(ds->devlink, resource_id,
+						 occ_get, occ_get_priv);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_resource_occ_get_register);
+
+void dsa_devlink_resource_occ_get_unregister(struct dsa_switch *ds,
+					     u64 resource_id)
+{
+	devlink_resource_occ_get_unregister(ds->devlink, resource_id);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_resource_occ_get_unregister);
+
+struct devlink_region *
+dsa_devlink_region_create(struct dsa_switch *ds,
+			  const struct devlink_region_ops *ops,
+			  u32 region_max_snapshots, u64 region_size)
+{
+	return devlink_region_create(ds->devlink, ops, region_max_snapshots,
+				     region_size);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_region_create);
+
+struct devlink_region *
+dsa_devlink_port_region_create(struct dsa_switch *ds,
+			       int port,
+			       const struct devlink_port_region_ops *ops,
+			       u32 region_max_snapshots, u64 region_size)
+{
+	struct dsa_port *dp = dsa_to_port(ds, port);
+
+	return devlink_port_region_create(&dp->devlink_port, ops,
+					  region_max_snapshots,
+					  region_size);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_port_region_create);
+
+void dsa_devlink_region_destroy(struct devlink_region *region)
+{
+	devlink_region_destroy(region);
+}
+EXPORT_SYMBOL_GPL(dsa_devlink_region_destroy);
+
+struct dsa_port *dsa_port_from_netdev(struct net_device *netdev)
+{
+	if (!netdev || !dsa_slave_dev_check(netdev))
+		return ERR_PTR(-ENODEV);
+
+	return dsa_slave_to_port(netdev);
+}
+EXPORT_SYMBOL_GPL(dsa_port_from_netdev);
+
+bool dsa_db_equal(const struct dsa_db *a, const struct dsa_db *b)
+{
+	if (a->type != b->type)
+		return false;
+
+	switch (a->type) {
+	case DSA_DB_PORT:
+		return a->dp == b->dp;
+	case DSA_DB_LAG:
+		return a->lag.dev == b->lag.dev;
+	case DSA_DB_BRIDGE:
+		return a->bridge.num == b->bridge.num;
+	default:
+		WARN_ON(1);
+		return false;
+	}
+}
+
+bool dsa_fdb_present_in_other_db(struct dsa_switch *ds, int port,
+				 const unsigned char *addr, u16 vid,
+				 struct dsa_db db)
+{
+	struct dsa_port *dp = dsa_to_port(ds, port);
+	struct dsa_mac_addr *a;
+
+	lockdep_assert_held(&dp->addr_lists_lock);
+
+	list_for_each_entry(a, &dp->fdbs, list) {
+		if (!ether_addr_equal(a->addr, addr) || a->vid != vid)
+			continue;
+
+		if (a->db.type == db.type && !dsa_db_equal(&a->db, &db))
+			return true;
+	}
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(dsa_fdb_present_in_other_db);
+
+bool dsa_mdb_present_in_other_db(struct dsa_switch *ds, int port,
+				 const struct switchdev_obj_port_mdb *mdb,
+				 struct dsa_db db)
+{
+	struct dsa_port *dp = dsa_to_port(ds, port);
+	struct dsa_mac_addr *a;
+
+	lockdep_assert_held(&dp->addr_lists_lock);
+
+	list_for_each_entry(a, &dp->mdbs, list) {
+		if (!ether_addr_equal(a->addr, mdb->addr) || a->vid != mdb->vid)
+			continue;
+
+		if (a->db.type == db.type && !dsa_db_equal(&a->db, &db))
+			return true;
+	}
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(dsa_mdb_present_in_other_db);
+
+static int __init dsa_init_module(void)
+{
+	int rc;
+
+	dsa_owq = alloc_ordered_workqueue("dsa_ordered",
+					  WQ_MEM_RECLAIM);
+	if (!dsa_owq)
+		return -ENOMEM;
+
+	rc = dsa_slave_register_notifier();
+	if (rc)
+		goto register_notifier_fail;
+
+	dev_add_pack(&dsa_pack_type);
+
+	dsa_tag_driver_register(&DSA_TAG_DRIVER_NAME(none_ops),
+				THIS_MODULE);
+
+	rc = rtnl_link_register(&dsa_link_ops);
+	if (rc)
+		goto netlink_register_fail;
+
+	return 0;
+
+netlink_register_fail:
+	dsa_tag_driver_unregister(&DSA_TAG_DRIVER_NAME(none_ops));
+	dsa_slave_unregister_notifier();
+	dev_remove_pack(&dsa_pack_type);
+register_notifier_fail:
+	destroy_workqueue(dsa_owq);
+
+	return rc;
+}
+module_init(dsa_init_module);
+
+static void __exit dsa_cleanup_module(void)
+{
+	rtnl_link_unregister(&dsa_link_ops);
+	dsa_tag_driver_unregister(&DSA_TAG_DRIVER_NAME(none_ops));
+
+	dsa_slave_unregister_notifier();
+	dev_remove_pack(&dsa_pack_type);
+	destroy_workqueue(dsa_owq);
+}
+module_exit(dsa_cleanup_module);
+
+MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
+MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:dsa");
diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
new file mode 100644
index 000000000..5417f7b11
--- /dev/null
+++ b/net/dsa/dsa2.c
@@ -0,0 +1,1829 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * net/dsa/dsa2.c - Hardware switch handling, binding version 2
+ * Copyright (c) 2008-2009 Marvell Semiconductor
+ * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
+ * Copyright (c) 2016 Andrew Lunn <andrew@lunn.ch>
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/list.h>
+#include <linux/netdevice.h>
+#include <linux/slab.h>
+#include <linux/rtnetlink.h>
+#include <linux/of.h>
+#include <linux/of_mdio.h>
+#include <linux/of_net.h>
+#include <net/devlink.h>
+#include <net/sch_generic.h>
+
+#include "dsa_priv.h"
+
+static DEFINE_MUTEX(dsa2_mutex);
+LIST_HEAD(dsa_tree_list);
+
+/* Track the bridges with forwarding offload enabled */
+static unsigned long dsa_fwd_offloading_bridges;
+
+/**
+ * dsa_tree_notify - Execute code for all switches in a DSA switch tree.
+ * @dst: collection of struct dsa_switch devices to notify.
+ * @e: event, must be of type DSA_NOTIFIER_*
+ * @v: event-specific value.
+ *
+ * Given a struct dsa_switch_tree, this can be used to run a function once for
+ * each member DSA switch. The other alternative of traversing the tree is only
+ * through its ports list, which does not uniquely list the switches.
+ */
+int dsa_tree_notify(struct dsa_switch_tree *dst, unsigned long e, void *v)
+{
+	struct raw_notifier_head *nh = &dst->nh;
+	int err;
+
+	err = raw_notifier_call_chain(nh, e, v);
+
+	return notifier_to_errno(err);
+}
+
+/**
+ * dsa_broadcast - Notify all DSA trees in the system.
+ * @e: event, must be of type DSA_NOTIFIER_*
+ * @v: event-specific value.
+ *
+ * Can be used to notify the switching fabric of events such as cross-chip
+ * bridging between disjoint trees (such as islands of tagger-compatible
+ * switches bridged by an incompatible middle switch).
+ *
+ * WARNING: this function is not reliable during probe time, because probing
+ * between trees is asynchronous and not all DSA trees might have probed.
+ */
+int dsa_broadcast(unsigned long e, void *v)
+{
+	struct dsa_switch_tree *dst;
+	int err = 0;
+
+	list_for_each_entry(dst, &dsa_tree_list, list) {
+		err = dsa_tree_notify(dst, e, v);
+		if (err)
+			break;
+	}
+
+	return err;
+}
+
+/**
+ * dsa_lag_map() - Map LAG structure to a linear LAG array
+ * @dst: Tree in which to record the mapping.
+ * @lag: LAG structure that is to be mapped to the tree's array.
+ *
+ * dsa_lag_id/dsa_lag_by_id can then be used to translate between the
+ * two spaces. The size of the mapping space is determined by the
+ * driver by setting ds->num_lag_ids. It is perfectly legal to leave
+ * it unset if it is not needed, in which case these functions become
+ * no-ops.
+ */
+void dsa_lag_map(struct dsa_switch_tree *dst, struct dsa_lag *lag)
+{
+	unsigned int id;
+
+	for (id = 1; id <= dst->lags_len; id++) {
+		if (!dsa_lag_by_id(dst, id)) {
+			dst->lags[id - 1] = lag;
+			lag->id = id;
+			return;
+		}
+	}
+
+	/* No IDs left, which is OK. Some drivers do not need it. The
+	 * ones that do, e.g. mv88e6xxx, will discover that dsa_lag_id
+	 * returns an error for this device when joining the LAG. The
+	 * driver can then return -EOPNOTSUPP back to DSA, which will
+	 * fall back to a software LAG.
+	 */
+}
+
+/**
+ * dsa_lag_unmap() - Remove a LAG ID mapping
+ * @dst: Tree in which the mapping is recorded.
+ * @lag: LAG structure that was mapped.
+ *
+ * As there may be multiple users of the mapping, it is only removed
+ * if there are no other references to it.
+ */
+void dsa_lag_unmap(struct dsa_switch_tree *dst, struct dsa_lag *lag)
+{
+	unsigned int id;
+
+	dsa_lags_foreach_id(id, dst) {
+		if (dsa_lag_by_id(dst, id) == lag) {
+			dst->lags[id - 1] = NULL;
+			lag->id = 0;
+			break;
+		}
+	}
+}
+
+struct dsa_lag *dsa_tree_lag_find(struct dsa_switch_tree *dst,
+				  const struct net_device *lag_dev)
+{
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dsa_port_lag_dev_get(dp) == lag_dev)
+			return dp->lag;
+
+	return NULL;
+}
+
+struct dsa_bridge *dsa_tree_bridge_find(struct dsa_switch_tree *dst,
+					const struct net_device *br)
+{
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dsa_port_bridge_dev_get(dp) == br)
+			return dp->bridge;
+
+	return NULL;
+}
+
+static int dsa_bridge_num_find(const struct net_device *bridge_dev)
+{
+	struct dsa_switch_tree *dst;
+
+	list_for_each_entry(dst, &dsa_tree_list, list) {
+		struct dsa_bridge *bridge;
+
+		bridge = dsa_tree_bridge_find(dst, bridge_dev);
+		if (bridge)
+			return bridge->num;
+	}
+
+	return 0;
+}
+
+unsigned int dsa_bridge_num_get(const struct net_device *bridge_dev, int max)
+{
+	unsigned int bridge_num = dsa_bridge_num_find(bridge_dev);
+
+	/* Switches without FDB isolation support don't get unique
+	 * bridge numbering
+	 */
+	if (!max)
+		return 0;
+
+	if (!bridge_num) {
+		/* First port that requests FDB isolation or TX forwarding
+		 * offload for this bridge
+		 */
+		bridge_num = find_next_zero_bit(&dsa_fwd_offloading_bridges,
+						DSA_MAX_NUM_OFFLOADING_BRIDGES,
+						1);
+		if (bridge_num >= max)
+			return 0;
+
+		set_bit(bridge_num, &dsa_fwd_offloading_bridges);
+	}
+
+	return bridge_num;
+}
+
+void dsa_bridge_num_put(const struct net_device *bridge_dev,
+			unsigned int bridge_num)
+{
+	/* Since we refcount bridges, we know that when we call this function
+	 * it is no longer in use, so we can just go ahead and remove it from
+	 * the bit mask.
+	 */
+	clear_bit(bridge_num, &dsa_fwd_offloading_bridges);
+}
+
+struct dsa_switch *dsa_switch_find(int tree_index, int sw_index)
+{
+	struct dsa_switch_tree *dst;
+	struct dsa_port *dp;
+
+	list_for_each_entry(dst, &dsa_tree_list, list) {
+		if (dst->index != tree_index)
+			continue;
+
+		list_for_each_entry(dp, &dst->ports, list) {
+			if (dp->ds->index != sw_index)
+				continue;
+
+			return dp->ds;
+		}
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(dsa_switch_find);
+
+static struct dsa_switch_tree *dsa_tree_find(int index)
+{
+	struct dsa_switch_tree *dst;
+
+	list_for_each_entry(dst, &dsa_tree_list, list)
+		if (dst->index == index)
+			return dst;
+
+	return NULL;
+}
+
+static struct dsa_switch_tree *dsa_tree_alloc(int index)
+{
+	struct dsa_switch_tree *dst;
+
+	dst = kzalloc(sizeof(*dst), GFP_KERNEL);
+	if (!dst)
+		return NULL;
+
+	dst->index = index;
+
+	INIT_LIST_HEAD(&dst->rtable);
+
+	INIT_LIST_HEAD(&dst->ports);
+
+	INIT_LIST_HEAD(&dst->list);
+	list_add_tail(&dst->list, &dsa_tree_list);
+
+	kref_init(&dst->refcount);
+
+	return dst;
+}
+
+static void dsa_tree_free(struct dsa_switch_tree *dst)
+{
+	if (dst->tag_ops)
+		dsa_tag_driver_put(dst->tag_ops);
+	list_del(&dst->list);
+	kfree(dst);
+}
+
+static struct dsa_switch_tree *dsa_tree_get(struct dsa_switch_tree *dst)
+{
+	if (dst)
+		kref_get(&dst->refcount);
+
+	return dst;
+}
+
+static struct dsa_switch_tree *dsa_tree_touch(int index)
+{
+	struct dsa_switch_tree *dst;
+
+	dst = dsa_tree_find(index);
+	if (dst)
+		return dsa_tree_get(dst);
+	else
+		return dsa_tree_alloc(index);
+}
+
+static void dsa_tree_release(struct kref *ref)
+{
+	struct dsa_switch_tree *dst;
+
+	dst = container_of(ref, struct dsa_switch_tree, refcount);
+
+	dsa_tree_free(dst);
+}
+
+static void dsa_tree_put(struct dsa_switch_tree *dst)
+{
+	if (dst)
+		kref_put(&dst->refcount, dsa_tree_release);
+}
+
+static struct dsa_port *dsa_tree_find_port_by_node(struct dsa_switch_tree *dst,
+						   struct device_node *dn)
+{
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dp->dn == dn)
+			return dp;
+
+	return NULL;
+}
+
+static struct dsa_link *dsa_link_touch(struct dsa_port *dp,
+				       struct dsa_port *link_dp)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_switch_tree *dst;
+	struct dsa_link *dl;
+
+	dst = ds->dst;
+
+	list_for_each_entry(dl, &dst->rtable, list)
+		if (dl->dp == dp && dl->link_dp == link_dp)
+			return dl;
+
+	dl = kzalloc(sizeof(*dl), GFP_KERNEL);
+	if (!dl)
+		return NULL;
+
+	dl->dp = dp;
+	dl->link_dp = link_dp;
+
+	INIT_LIST_HEAD(&dl->list);
+	list_add_tail(&dl->list, &dst->rtable);
+
+	return dl;
+}
+
+static bool dsa_port_setup_routing_table(struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_switch_tree *dst = ds->dst;
+	struct device_node *dn = dp->dn;
+	struct of_phandle_iterator it;
+	struct dsa_port *link_dp;
+	struct dsa_link *dl;
+	int err;
+
+	of_for_each_phandle(&it, err, dn, "link", NULL, 0) {
+		link_dp = dsa_tree_find_port_by_node(dst, it.node);
+		if (!link_dp) {
+			of_node_put(it.node);
+			return false;
+		}
+
+		dl = dsa_link_touch(dp, link_dp);
+		if (!dl) {
+			of_node_put(it.node);
+			return false;
+		}
+	}
+
+	return true;
+}
+
+static bool dsa_tree_setup_routing_table(struct dsa_switch_tree *dst)
+{
+	bool complete = true;
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list) {
+		if (dsa_port_is_dsa(dp)) {
+			complete = dsa_port_setup_routing_table(dp);
+			if (!complete)
+				break;
+		}
+	}
+
+	return complete;
+}
+
+static struct dsa_port *dsa_tree_find_first_cpu(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dsa_port_is_cpu(dp))
+			return dp;
+
+	return NULL;
+}
+
+struct net_device *dsa_tree_find_first_master(struct dsa_switch_tree *dst)
+{
+	struct device_node *ethernet;
+	struct net_device *master;
+	struct dsa_port *cpu_dp;
+
+	cpu_dp = dsa_tree_find_first_cpu(dst);
+	ethernet = of_parse_phandle(cpu_dp->dn, "ethernet", 0);
+	master = of_find_net_device_by_node(ethernet);
+	of_node_put(ethernet);
+
+	return master;
+}
+
+/* Assign the default CPU port (the first one in the tree) to all ports of the
+ * fabric which don't already have one as part of their own switch.
+ */
+static int dsa_tree_setup_default_cpu(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *cpu_dp, *dp;
+
+	cpu_dp = dsa_tree_find_first_cpu(dst);
+	if (!cpu_dp) {
+		pr_err("DSA: tree %d has no CPU port\n", dst->index);
+		return -EINVAL;
+	}
+
+	list_for_each_entry(dp, &dst->ports, list) {
+		if (dp->cpu_dp)
+			continue;
+
+		if (dsa_port_is_user(dp) || dsa_port_is_dsa(dp))
+			dp->cpu_dp = cpu_dp;
+	}
+
+	return 0;
+}
+
+/* Perform initial assignment of CPU ports to user ports and DSA links in the
+ * fabric, giving preference to CPU ports local to each switch. Default to
+ * using the first CPU port in the switch tree if the port does not have a CPU
+ * port local to this switch.
+ */
+static int dsa_tree_setup_cpu_ports(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *cpu_dp, *dp;
+
+	list_for_each_entry(cpu_dp, &dst->ports, list) {
+		if (!dsa_port_is_cpu(cpu_dp))
+			continue;
+
+		/* Prefer a local CPU port */
+		dsa_switch_for_each_port(dp, cpu_dp->ds) {
+			/* Prefer the first local CPU port found */
+			if (dp->cpu_dp)
+				continue;
+
+			if (dsa_port_is_user(dp) || dsa_port_is_dsa(dp))
+				dp->cpu_dp = cpu_dp;
+		}
+	}
+
+	return dsa_tree_setup_default_cpu(dst);
+}
+
+static void dsa_tree_teardown_cpu_ports(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dsa_port_is_user(dp) || dsa_port_is_dsa(dp))
+			dp->cpu_dp = NULL;
+}
+
+static int dsa_port_devlink_setup(struct dsa_port *dp)
+{
+	struct devlink_port *dlp = &dp->devlink_port;
+	struct dsa_switch_tree *dst = dp->ds->dst;
+	struct devlink_port_attrs attrs = {};
+	struct devlink *dl = dp->ds->devlink;
+	struct dsa_switch *ds = dp->ds;
+	const unsigned char *id;
+	unsigned char len;
+	int err;
+
+	memset(dlp, 0, sizeof(*dlp));
+	devlink_port_init(dl, dlp);
+
+	if (ds->ops->port_setup) {
+		err = ds->ops->port_setup(ds, dp->index);
+		if (err)
+			return err;
+	}
+
+	id = (const unsigned char *)&dst->index;
+	len = sizeof(dst->index);
+
+	attrs.phys.port_number = dp->index;
+	memcpy(attrs.switch_id.id, id, len);
+	attrs.switch_id.id_len = len;
+
+	switch (dp->type) {
+	case DSA_PORT_TYPE_UNUSED:
+		attrs.flavour = DEVLINK_PORT_FLAVOUR_UNUSED;
+		break;
+	case DSA_PORT_TYPE_CPU:
+		attrs.flavour = DEVLINK_PORT_FLAVOUR_CPU;
+		break;
+	case DSA_PORT_TYPE_DSA:
+		attrs.flavour = DEVLINK_PORT_FLAVOUR_DSA;
+		break;
+	case DSA_PORT_TYPE_USER:
+		attrs.flavour = DEVLINK_PORT_FLAVOUR_PHYSICAL;
+		break;
+	}
+
+	devlink_port_attrs_set(dlp, &attrs);
+	err = devlink_port_register(dl, dlp, dp->index);
+	if (err) {
+		if (ds->ops->port_teardown)
+			ds->ops->port_teardown(ds, dp->index);
+		return err;
+	}
+
+	return 0;
+}
+
+static void dsa_port_devlink_teardown(struct dsa_port *dp)
+{
+	struct devlink_port *dlp = &dp->devlink_port;
+	struct dsa_switch *ds = dp->ds;
+
+	devlink_port_unregister(dlp);
+
+	if (ds->ops->port_teardown)
+		ds->ops->port_teardown(ds, dp->index);
+
+	devlink_port_fini(dlp);
+}
+
+static int dsa_port_setup(struct dsa_port *dp)
+{
+	struct devlink_port *dlp = &dp->devlink_port;
+	bool dsa_port_link_registered = false;
+	struct dsa_switch *ds = dp->ds;
+	bool dsa_port_enabled = false;
+	int err = 0;
+
+	if (dp->setup)
+		return 0;
+
+	err = dsa_port_devlink_setup(dp);
+	if (err)
+		return err;
+
+	switch (dp->type) {
+	case DSA_PORT_TYPE_UNUSED:
+		dsa_port_disable(dp);
+		break;
+	case DSA_PORT_TYPE_CPU:
+		if (dp->dn) {
+			err = dsa_shared_port_link_register_of(dp);
+			if (err)
+				break;
+			dsa_port_link_registered = true;
+		} else {
+			dev_warn(ds->dev,
+				 "skipping link registration for CPU port %d\n",
+				 dp->index);
+		}
+
+		err = dsa_port_enable(dp, NULL);
+		if (err)
+			break;
+		dsa_port_enabled = true;
+
+		break;
+	case DSA_PORT_TYPE_DSA:
+		if (dp->dn) {
+			err = dsa_shared_port_link_register_of(dp);
+			if (err)
+				break;
+			dsa_port_link_registered = true;
+		} else {
+			dev_warn(ds->dev,
+				 "skipping link registration for DSA port %d\n",
+				 dp->index);
+		}
+
+		err = dsa_port_enable(dp, NULL);
+		if (err)
+			break;
+		dsa_port_enabled = true;
+
+		break;
+	case DSA_PORT_TYPE_USER:
+		of_get_mac_address(dp->dn, dp->mac);
+		err = dsa_slave_create(dp);
+		if (err)
+			break;
+
+		devlink_port_type_eth_set(dlp, dp->slave);
+		break;
+	}
+
+	if (err && dsa_port_enabled)
+		dsa_port_disable(dp);
+	if (err && dsa_port_link_registered)
+		dsa_shared_port_link_unregister_of(dp);
+	if (err) {
+		dsa_port_devlink_teardown(dp);
+		return err;
+	}
+
+	dp->setup = true;
+
+	return 0;
+}
+
+static void dsa_port_teardown(struct dsa_port *dp)
+{
+	struct devlink_port *dlp = &dp->devlink_port;
+
+	if (!dp->setup)
+		return;
+
+	devlink_port_type_clear(dlp);
+
+	switch (dp->type) {
+	case DSA_PORT_TYPE_UNUSED:
+		break;
+	case DSA_PORT_TYPE_CPU:
+		dsa_port_disable(dp);
+		if (dp->dn)
+			dsa_shared_port_link_unregister_of(dp);
+		break;
+	case DSA_PORT_TYPE_DSA:
+		dsa_port_disable(dp);
+		if (dp->dn)
+			dsa_shared_port_link_unregister_of(dp);
+		break;
+	case DSA_PORT_TYPE_USER:
+		if (dp->slave) {
+			dsa_slave_destroy(dp->slave);
+			dp->slave = NULL;
+		}
+		break;
+	}
+
+	dsa_port_devlink_teardown(dp);
+
+	dp->setup = false;
+}
+
+static int dsa_port_setup_as_unused(struct dsa_port *dp)
+{
+	dp->type = DSA_PORT_TYPE_UNUSED;
+	return dsa_port_setup(dp);
+}
+
+static int dsa_devlink_info_get(struct devlink *dl,
+				struct devlink_info_req *req,
+				struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dsa_devlink_to_ds(dl);
+
+	if (ds->ops->devlink_info_get)
+		return ds->ops->devlink_info_get(ds, req, extack);
+
+	return -EOPNOTSUPP;
+}
+
+static int dsa_devlink_sb_pool_get(struct devlink *dl,
+				   unsigned int sb_index, u16 pool_index,
+				   struct devlink_sb_pool_info *pool_info)
+{
+	struct dsa_switch *ds = dsa_devlink_to_ds(dl);
+
+	if (!ds->ops->devlink_sb_pool_get)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_sb_pool_get(ds, sb_index, pool_index,
+					    pool_info);
+}
+
+static int dsa_devlink_sb_pool_set(struct devlink *dl, unsigned int sb_index,
+				   u16 pool_index, u32 size,
+				   enum devlink_sb_threshold_type threshold_type,
+				   struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dsa_devlink_to_ds(dl);
+
+	if (!ds->ops->devlink_sb_pool_set)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_sb_pool_set(ds, sb_index, pool_index, size,
+					    threshold_type, extack);
+}
+
+static int dsa_devlink_sb_port_pool_get(struct devlink_port *dlp,
+					unsigned int sb_index, u16 pool_index,
+					u32 *p_threshold)
+{
+	struct dsa_switch *ds = dsa_devlink_port_to_ds(dlp);
+	int port = dsa_devlink_port_to_port(dlp);
+
+	if (!ds->ops->devlink_sb_port_pool_get)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_sb_port_pool_get(ds, port, sb_index,
+						 pool_index, p_threshold);
+}
+
+static int dsa_devlink_sb_port_pool_set(struct devlink_port *dlp,
+					unsigned int sb_index, u16 pool_index,
+					u32 threshold,
+					struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dsa_devlink_port_to_ds(dlp);
+	int port = dsa_devlink_port_to_port(dlp);
+
+	if (!ds->ops->devlink_sb_port_pool_set)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_sb_port_pool_set(ds, port, sb_index,
+						 pool_index, threshold, extack);
+}
+
+static int
+dsa_devlink_sb_tc_pool_bind_get(struct devlink_port *dlp,
+				unsigned int sb_index, u16 tc_index,
+				enum devlink_sb_pool_type pool_type,
+				u16 *p_pool_index, u32 *p_threshold)
+{
+	struct dsa_switch *ds = dsa_devlink_port_to_ds(dlp);
+	int port = dsa_devlink_port_to_port(dlp);
+
+	if (!ds->ops->devlink_sb_tc_pool_bind_get)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_sb_tc_pool_bind_get(ds, port, sb_index,
+						    tc_index, pool_type,
+						    p_pool_index, p_threshold);
+}
+
+static int
+dsa_devlink_sb_tc_pool_bind_set(struct devlink_port *dlp,
+				unsigned int sb_index, u16 tc_index,
+				enum devlink_sb_pool_type pool_type,
+				u16 pool_index, u32 threshold,
+				struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dsa_devlink_port_to_ds(dlp);
+	int port = dsa_devlink_port_to_port(dlp);
+
+	if (!ds->ops->devlink_sb_tc_pool_bind_set)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_sb_tc_pool_bind_set(ds, port, sb_index,
+						    tc_index, pool_type,
+						    pool_index, threshold,
+						    extack);
+}
+
+static int dsa_devlink_sb_occ_snapshot(struct devlink *dl,
+				       unsigned int sb_index)
+{
+	struct dsa_switch *ds = dsa_devlink_to_ds(dl);
+
+	if (!ds->ops->devlink_sb_occ_snapshot)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_sb_occ_snapshot(ds, sb_index);
+}
+
+static int dsa_devlink_sb_occ_max_clear(struct devlink *dl,
+					unsigned int sb_index)
+{
+	struct dsa_switch *ds = dsa_devlink_to_ds(dl);
+
+	if (!ds->ops->devlink_sb_occ_max_clear)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_sb_occ_max_clear(ds, sb_index);
+}
+
+static int dsa_devlink_sb_occ_port_pool_get(struct devlink_port *dlp,
+					    unsigned int sb_index,
+					    u16 pool_index, u32 *p_cur,
+					    u32 *p_max)
+{
+	struct dsa_switch *ds = dsa_devlink_port_to_ds(dlp);
+	int port = dsa_devlink_port_to_port(dlp);
+
+	if (!ds->ops->devlink_sb_occ_port_pool_get)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_sb_occ_port_pool_get(ds, port, sb_index,
+						     pool_index, p_cur, p_max);
+}
+
+static int
+dsa_devlink_sb_occ_tc_port_bind_get(struct devlink_port *dlp,
+				    unsigned int sb_index, u16 tc_index,
+				    enum devlink_sb_pool_type pool_type,
+				    u32 *p_cur, u32 *p_max)
+{
+	struct dsa_switch *ds = dsa_devlink_port_to_ds(dlp);
+	int port = dsa_devlink_port_to_port(dlp);
+
+	if (!ds->ops->devlink_sb_occ_tc_port_bind_get)
+		return -EOPNOTSUPP;
+
+	return ds->ops->devlink_sb_occ_tc_port_bind_get(ds, port,
+							sb_index, tc_index,
+							pool_type, p_cur,
+							p_max);
+}
+
+static const struct devlink_ops dsa_devlink_ops = {
+	.info_get			= dsa_devlink_info_get,
+	.sb_pool_get			= dsa_devlink_sb_pool_get,
+	.sb_pool_set			= dsa_devlink_sb_pool_set,
+	.sb_port_pool_get		= dsa_devlink_sb_port_pool_get,
+	.sb_port_pool_set		= dsa_devlink_sb_port_pool_set,
+	.sb_tc_pool_bind_get		= dsa_devlink_sb_tc_pool_bind_get,
+	.sb_tc_pool_bind_set		= dsa_devlink_sb_tc_pool_bind_set,
+	.sb_occ_snapshot		= dsa_devlink_sb_occ_snapshot,
+	.sb_occ_max_clear		= dsa_devlink_sb_occ_max_clear,
+	.sb_occ_port_pool_get		= dsa_devlink_sb_occ_port_pool_get,
+	.sb_occ_tc_port_bind_get	= dsa_devlink_sb_occ_tc_port_bind_get,
+};
+
+static int dsa_switch_setup_tag_protocol(struct dsa_switch *ds)
+{
+	const struct dsa_device_ops *tag_ops = ds->dst->tag_ops;
+	struct dsa_switch_tree *dst = ds->dst;
+	int err;
+
+	if (tag_ops->proto == dst->default_proto)
+		goto connect;
+
+	rtnl_lock();
+	err = ds->ops->change_tag_protocol(ds, tag_ops->proto);
+	rtnl_unlock();
+	if (err) {
+		dev_err(ds->dev, "Unable to use tag protocol \"%s\": %pe\n",
+			tag_ops->name, ERR_PTR(err));
+		return err;
+	}
+
+connect:
+	if (tag_ops->connect) {
+		err = tag_ops->connect(ds);
+		if (err)
+			return err;
+	}
+
+	if (ds->ops->connect_tag_protocol) {
+		err = ds->ops->connect_tag_protocol(ds, tag_ops->proto);
+		if (err) {
+			dev_err(ds->dev,
+				"Unable to connect to tag protocol \"%s\": %pe\n",
+				tag_ops->name, ERR_PTR(err));
+			goto disconnect;
+		}
+	}
+
+	return 0;
+
+disconnect:
+	if (tag_ops->disconnect)
+		tag_ops->disconnect(ds);
+
+	return err;
+}
+
+static void dsa_switch_teardown_tag_protocol(struct dsa_switch *ds)
+{
+	const struct dsa_device_ops *tag_ops = ds->dst->tag_ops;
+
+	if (tag_ops->disconnect)
+		tag_ops->disconnect(ds);
+}
+
+static int dsa_switch_setup(struct dsa_switch *ds)
+{
+	struct dsa_devlink_priv *dl_priv;
+	struct device_node *dn;
+	int err;
+
+	if (ds->setup)
+		return 0;
+
+	/* Initialize ds->phys_mii_mask before registering the slave MDIO bus
+	 * driver and before ops->setup() has run, since the switch drivers and
+	 * the slave MDIO bus driver rely on these values for probing PHY
+	 * devices or not
+	 */
+	ds->phys_mii_mask |= dsa_user_ports(ds);
+
+	/* Add the switch to devlink before calling setup, so that setup can
+	 * add dpipe tables
+	 */
+	ds->devlink =
+		devlink_alloc(&dsa_devlink_ops, sizeof(*dl_priv), ds->dev);
+	if (!ds->devlink)
+		return -ENOMEM;
+	dl_priv = devlink_priv(ds->devlink);
+	dl_priv->ds = ds;
+
+	err = dsa_switch_register_notifier(ds);
+	if (err)
+		goto devlink_free;
+
+	ds->configure_vlan_while_not_filtering = true;
+
+	err = ds->ops->setup(ds);
+	if (err < 0)
+		goto unregister_notifier;
+
+	err = dsa_switch_setup_tag_protocol(ds);
+	if (err)
+		goto teardown;
+
+	if (!ds->slave_mii_bus && ds->ops->phy_read) {
+		ds->slave_mii_bus = mdiobus_alloc();
+		if (!ds->slave_mii_bus) {
+			err = -ENOMEM;
+			goto teardown;
+		}
+
+		dsa_slave_mii_bus_init(ds);
+
+		dn = of_get_child_by_name(ds->dev->of_node, "mdio");
+
+		err = of_mdiobus_register(ds->slave_mii_bus, dn);
+		of_node_put(dn);
+		if (err < 0)
+			goto free_slave_mii_bus;
+	}
+
+	ds->setup = true;
+	devlink_register(ds->devlink);
+	return 0;
+
+free_slave_mii_bus:
+	if (ds->slave_mii_bus && ds->ops->phy_read)
+		mdiobus_free(ds->slave_mii_bus);
+teardown:
+	if (ds->ops->teardown)
+		ds->ops->teardown(ds);
+unregister_notifier:
+	dsa_switch_unregister_notifier(ds);
+devlink_free:
+	devlink_free(ds->devlink);
+	ds->devlink = NULL;
+	return err;
+}
+
+static void dsa_switch_teardown(struct dsa_switch *ds)
+{
+	if (!ds->setup)
+		return;
+
+	if (ds->devlink)
+		devlink_unregister(ds->devlink);
+
+	if (ds->slave_mii_bus && ds->ops->phy_read) {
+		mdiobus_unregister(ds->slave_mii_bus);
+		mdiobus_free(ds->slave_mii_bus);
+		ds->slave_mii_bus = NULL;
+	}
+
+	dsa_switch_teardown_tag_protocol(ds);
+
+	if (ds->ops->teardown)
+		ds->ops->teardown(ds);
+
+	dsa_switch_unregister_notifier(ds);
+
+	if (ds->devlink) {
+		devlink_free(ds->devlink);
+		ds->devlink = NULL;
+	}
+
+	ds->setup = false;
+}
+
+/* First tear down the non-shared, then the shared ports. This ensures that
+ * all work items scheduled by our switchdev handlers for user ports have
+ * completed before we destroy the refcounting kept on the shared ports.
+ */
+static void dsa_tree_teardown_ports(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dsa_port_is_user(dp) || dsa_port_is_unused(dp))
+			dsa_port_teardown(dp);
+
+	dsa_flush_workqueue();
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dsa_port_is_dsa(dp) || dsa_port_is_cpu(dp))
+			dsa_port_teardown(dp);
+}
+
+static void dsa_tree_teardown_switches(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		dsa_switch_teardown(dp->ds);
+}
+
+/* Bring shared ports up first, then non-shared ports */
+static int dsa_tree_setup_ports(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *dp;
+	int err = 0;
+
+	list_for_each_entry(dp, &dst->ports, list) {
+		if (dsa_port_is_dsa(dp) || dsa_port_is_cpu(dp)) {
+			err = dsa_port_setup(dp);
+			if (err)
+				goto teardown;
+		}
+	}
+
+	list_for_each_entry(dp, &dst->ports, list) {
+		if (dsa_port_is_user(dp) || dsa_port_is_unused(dp)) {
+			err = dsa_port_setup(dp);
+			if (err) {
+				err = dsa_port_setup_as_unused(dp);
+				if (err)
+					goto teardown;
+			}
+		}
+	}
+
+	return 0;
+
+teardown:
+	dsa_tree_teardown_ports(dst);
+
+	return err;
+}
+
+static int dsa_tree_setup_switches(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *dp;
+	int err = 0;
+
+	list_for_each_entry(dp, &dst->ports, list) {
+		err = dsa_switch_setup(dp->ds);
+		if (err) {
+			dsa_tree_teardown_switches(dst);
+			break;
+		}
+	}
+
+	return err;
+}
+
+static int dsa_tree_setup_master(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *cpu_dp;
+	int err = 0;
+
+	rtnl_lock();
+
+	dsa_tree_for_each_cpu_port(cpu_dp, dst) {
+		struct net_device *master = cpu_dp->master;
+		bool admin_up = (master->flags & IFF_UP) &&
+				!qdisc_tx_is_noop(master);
+
+		err = dsa_master_setup(master, cpu_dp);
+		if (err)
+			break;
+
+		/* Replay master state event */
+		dsa_tree_master_admin_state_change(dst, master, admin_up);
+		dsa_tree_master_oper_state_change(dst, master,
+						  netif_oper_up(master));
+	}
+
+	rtnl_unlock();
+
+	return err;
+}
+
+static void dsa_tree_teardown_master(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *cpu_dp;
+
+	rtnl_lock();
+
+	dsa_tree_for_each_cpu_port(cpu_dp, dst) {
+		struct net_device *master = cpu_dp->master;
+
+		/* Synthesizing an "admin down" state is sufficient for
+		 * the switches to get a notification if the master is
+		 * currently up and running.
+		 */
+		dsa_tree_master_admin_state_change(dst, master, false);
+
+		dsa_master_teardown(master);
+	}
+
+	rtnl_unlock();
+}
+
+static int dsa_tree_setup_lags(struct dsa_switch_tree *dst)
+{
+	unsigned int len = 0;
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list) {
+		if (dp->ds->num_lag_ids > len)
+			len = dp->ds->num_lag_ids;
+	}
+
+	if (!len)
+		return 0;
+
+	dst->lags = kcalloc(len, sizeof(*dst->lags), GFP_KERNEL);
+	if (!dst->lags)
+		return -ENOMEM;
+
+	dst->lags_len = len;
+	return 0;
+}
+
+static void dsa_tree_teardown_lags(struct dsa_switch_tree *dst)
+{
+	kfree(dst->lags);
+}
+
+static int dsa_tree_setup(struct dsa_switch_tree *dst)
+{
+	bool complete;
+	int err;
+
+	if (dst->setup) {
+		pr_err("DSA: tree %d already setup! Disjoint trees?\n",
+		       dst->index);
+		return -EEXIST;
+	}
+
+	complete = dsa_tree_setup_routing_table(dst);
+	if (!complete)
+		return 0;
+
+	err = dsa_tree_setup_cpu_ports(dst);
+	if (err)
+		return err;
+
+	err = dsa_tree_setup_switches(dst);
+	if (err)
+		goto teardown_cpu_ports;
+
+	err = dsa_tree_setup_ports(dst);
+	if (err)
+		goto teardown_switches;
+
+	err = dsa_tree_setup_master(dst);
+	if (err)
+		goto teardown_ports;
+
+	err = dsa_tree_setup_lags(dst);
+	if (err)
+		goto teardown_master;
+
+	dst->setup = true;
+
+	pr_info("DSA: tree %d setup\n", dst->index);
+
+	return 0;
+
+teardown_master:
+	dsa_tree_teardown_master(dst);
+teardown_ports:
+	dsa_tree_teardown_ports(dst);
+teardown_switches:
+	dsa_tree_teardown_switches(dst);
+teardown_cpu_ports:
+	dsa_tree_teardown_cpu_ports(dst);
+
+	return err;
+}
+
+static void dsa_tree_teardown(struct dsa_switch_tree *dst)
+{
+	struct dsa_link *dl, *next;
+
+	if (!dst->setup)
+		return;
+
+	dsa_tree_teardown_lags(dst);
+
+	dsa_tree_teardown_master(dst);
+
+	dsa_tree_teardown_ports(dst);
+
+	dsa_tree_teardown_switches(dst);
+
+	dsa_tree_teardown_cpu_ports(dst);
+
+	list_for_each_entry_safe(dl, next, &dst->rtable, list) {
+		list_del(&dl->list);
+		kfree(dl);
+	}
+
+	pr_info("DSA: tree %d torn down\n", dst->index);
+
+	dst->setup = false;
+}
+
+static int dsa_tree_bind_tag_proto(struct dsa_switch_tree *dst,
+				   const struct dsa_device_ops *tag_ops)
+{
+	const struct dsa_device_ops *old_tag_ops = dst->tag_ops;
+	struct dsa_notifier_tag_proto_info info;
+	int err;
+
+	dst->tag_ops = tag_ops;
+
+	/* Notify the switches from this tree about the connection
+	 * to the new tagger
+	 */
+	info.tag_ops = tag_ops;
+	err = dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO_CONNECT, &info);
+	if (err && err != -EOPNOTSUPP)
+		goto out_disconnect;
+
+	/* Notify the old tagger about the disconnection from this tree */
+	info.tag_ops = old_tag_ops;
+	dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO_DISCONNECT, &info);
+
+	return 0;
+
+out_disconnect:
+	info.tag_ops = tag_ops;
+	dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO_DISCONNECT, &info);
+	dst->tag_ops = old_tag_ops;
+
+	return err;
+}
+
+/* Since the dsa/tagging sysfs device attribute is per master, the assumption
+ * is that all DSA switches within a tree share the same tagger, otherwise
+ * they would have formed disjoint trees (different "dsa,member" values).
+ */
+int dsa_tree_change_tag_proto(struct dsa_switch_tree *dst,
+			      const struct dsa_device_ops *tag_ops,
+			      const struct dsa_device_ops *old_tag_ops)
+{
+	struct dsa_notifier_tag_proto_info info;
+	struct dsa_port *dp;
+	int err = -EBUSY;
+
+	if (!rtnl_trylock())
+		return restart_syscall();
+
+	/* At the moment we don't allow changing the tag protocol under
+	 * traffic. The rtnl_mutex also happens to serialize concurrent
+	 * attempts to change the tagging protocol. If we ever lift the IFF_UP
+	 * restriction, there needs to be another mutex which serializes this.
+	 */
+	dsa_tree_for_each_user_port(dp, dst) {
+		if (dsa_port_to_master(dp)->flags & IFF_UP)
+			goto out_unlock;
+
+		if (dp->slave->flags & IFF_UP)
+			goto out_unlock;
+	}
+
+	/* Notify the tag protocol change */
+	info.tag_ops = tag_ops;
+	err = dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO, &info);
+	if (err)
+		goto out_unwind_tagger;
+
+	err = dsa_tree_bind_tag_proto(dst, tag_ops);
+	if (err)
+		goto out_unwind_tagger;
+
+	rtnl_unlock();
+
+	return 0;
+
+out_unwind_tagger:
+	info.tag_ops = old_tag_ops;
+	dsa_tree_notify(dst, DSA_NOTIFIER_TAG_PROTO, &info);
+out_unlock:
+	rtnl_unlock();
+	return err;
+}
+
+static void dsa_tree_master_state_change(struct dsa_switch_tree *dst,
+					 struct net_device *master)
+{
+	struct dsa_notifier_master_state_info info;
+	struct dsa_port *cpu_dp = master->dsa_ptr;
+
+	info.master = master;
+	info.operational = dsa_port_master_is_operational(cpu_dp);
+
+	dsa_tree_notify(dst, DSA_NOTIFIER_MASTER_STATE_CHANGE, &info);
+}
+
+void dsa_tree_master_admin_state_change(struct dsa_switch_tree *dst,
+					struct net_device *master,
+					bool up)
+{
+	struct dsa_port *cpu_dp = master->dsa_ptr;
+	bool notify = false;
+
+	/* Don't keep track of admin state on LAG DSA masters,
+	 * but rather just of physical DSA masters
+	 */
+	if (netif_is_lag_master(master))
+		return;
+
+	if ((dsa_port_master_is_operational(cpu_dp)) !=
+	    (up && cpu_dp->master_oper_up))
+		notify = true;
+
+	cpu_dp->master_admin_up = up;
+
+	if (notify)
+		dsa_tree_master_state_change(dst, master);
+}
+
+void dsa_tree_master_oper_state_change(struct dsa_switch_tree *dst,
+				       struct net_device *master,
+				       bool up)
+{
+	struct dsa_port *cpu_dp = master->dsa_ptr;
+	bool notify = false;
+
+	/* Don't keep track of oper state on LAG DSA masters,
+	 * but rather just of physical DSA masters
+	 */
+	if (netif_is_lag_master(master))
+		return;
+
+	if ((dsa_port_master_is_operational(cpu_dp)) !=
+	    (cpu_dp->master_admin_up && up))
+		notify = true;
+
+	cpu_dp->master_oper_up = up;
+
+	if (notify)
+		dsa_tree_master_state_change(dst, master);
+}
+
+static struct dsa_port *dsa_port_touch(struct dsa_switch *ds, int index)
+{
+	struct dsa_switch_tree *dst = ds->dst;
+	struct dsa_port *dp;
+
+	dsa_switch_for_each_port(dp, ds)
+		if (dp->index == index)
+			return dp;
+
+	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
+	if (!dp)
+		return NULL;
+
+	dp->ds = ds;
+	dp->index = index;
+
+	mutex_init(&dp->addr_lists_lock);
+	mutex_init(&dp->vlans_lock);
+	INIT_LIST_HEAD(&dp->fdbs);
+	INIT_LIST_HEAD(&dp->mdbs);
+	INIT_LIST_HEAD(&dp->vlans);
+	INIT_LIST_HEAD(&dp->list);
+	list_add_tail(&dp->list, &dst->ports);
+
+	return dp;
+}
+
+static int dsa_port_parse_user(struct dsa_port *dp, const char *name)
+{
+	if (!name)
+		name = "eth%d";
+
+	dp->type = DSA_PORT_TYPE_USER;
+	dp->name = name;
+
+	return 0;
+}
+
+static int dsa_port_parse_dsa(struct dsa_port *dp)
+{
+	dp->type = DSA_PORT_TYPE_DSA;
+
+	return 0;
+}
+
+static enum dsa_tag_protocol dsa_get_tag_protocol(struct dsa_port *dp,
+						  struct net_device *master)
+{
+	enum dsa_tag_protocol tag_protocol = DSA_TAG_PROTO_NONE;
+	struct dsa_switch *mds, *ds = dp->ds;
+	unsigned int mdp_upstream;
+	struct dsa_port *mdp;
+
+	/* It is possible to stack DSA switches onto one another when that
+	 * happens the switch driver may want to know if its tagging protocol
+	 * is going to work in such a configuration.
+	 */
+	if (dsa_slave_dev_check(master)) {
+		mdp = dsa_slave_to_port(master);
+		mds = mdp->ds;
+		mdp_upstream = dsa_upstream_port(mds, mdp->index);
+		tag_protocol = mds->ops->get_tag_protocol(mds, mdp_upstream,
+							  DSA_TAG_PROTO_NONE);
+	}
+
+	/* If the master device is not itself a DSA slave in a disjoint DSA
+	 * tree, then return immediately.
+	 */
+	return ds->ops->get_tag_protocol(ds, dp->index, tag_protocol);
+}
+
+static int dsa_port_parse_cpu(struct dsa_port *dp, struct net_device *master,
+			      const char *user_protocol)
+{
+	const struct dsa_device_ops *tag_ops = NULL;
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_switch_tree *dst = ds->dst;
+	enum dsa_tag_protocol default_proto;
+
+	/* Find out which protocol the switch would prefer. */
+	default_proto = dsa_get_tag_protocol(dp, master);
+	if (dst->default_proto) {
+		if (dst->default_proto != default_proto) {
+			dev_err(ds->dev,
+				"A DSA switch tree can have only one tagging protocol\n");
+			return -EINVAL;
+		}
+	} else {
+		dst->default_proto = default_proto;
+	}
+
+	/* See if the user wants to override that preference. */
+	if (user_protocol) {
+		if (!ds->ops->change_tag_protocol) {
+			dev_err(ds->dev, "Tag protocol cannot be modified\n");
+			return -EINVAL;
+		}
+
+		tag_ops = dsa_find_tagger_by_name(user_protocol);
+		if (IS_ERR(tag_ops)) {
+			dev_warn(ds->dev,
+				 "Failed to find a tagging driver for protocol %s, using default\n",
+				 user_protocol);
+			tag_ops = NULL;
+		}
+	}
+
+	if (!tag_ops)
+		tag_ops = dsa_tag_driver_get(default_proto);
+
+	if (IS_ERR(tag_ops)) {
+		if (PTR_ERR(tag_ops) == -ENOPROTOOPT)
+			return -EPROBE_DEFER;
+
+		dev_warn(ds->dev, "No tagger for this switch\n");
+		return PTR_ERR(tag_ops);
+	}
+
+	if (dst->tag_ops) {
+		if (dst->tag_ops != tag_ops) {
+			dev_err(ds->dev,
+				"A DSA switch tree can have only one tagging protocol\n");
+
+			dsa_tag_driver_put(tag_ops);
+			return -EINVAL;
+		}
+
+		/* In the case of multiple CPU ports per switch, the tagging
+		 * protocol is still reference-counted only per switch tree.
+		 */
+		dsa_tag_driver_put(tag_ops);
+	} else {
+		dst->tag_ops = tag_ops;
+	}
+
+	dp->master = master;
+	dp->type = DSA_PORT_TYPE_CPU;
+	dsa_port_set_tag_protocol(dp, dst->tag_ops);
+	dp->dst = dst;
+
+	/* At this point, the tree may be configured to use a different
+	 * tagger than the one chosen by the switch driver during
+	 * .setup, in the case when a user selects a custom protocol
+	 * through the DT.
+	 *
+	 * This is resolved by syncing the driver with the tree in
+	 * dsa_switch_setup_tag_protocol once .setup has run and the
+	 * driver is ready to accept calls to .change_tag_protocol. If
+	 * the driver does not support the custom protocol at that
+	 * point, the tree is wholly rejected, thereby ensuring that the
+	 * tree and driver are always in agreement on the protocol to
+	 * use.
+	 */
+	return 0;
+}
+
+static int dsa_port_parse_of(struct dsa_port *dp, struct device_node *dn)
+{
+	struct device_node *ethernet = of_parse_phandle(dn, "ethernet", 0);
+	const char *name = of_get_property(dn, "label", NULL);
+	bool link = of_property_read_bool(dn, "link");
+
+	dp->dn = dn;
+
+	if (ethernet) {
+		struct net_device *master;
+		const char *user_protocol;
+
+		master = of_find_net_device_by_node(ethernet);
+		of_node_put(ethernet);
+		if (!master)
+			return -EPROBE_DEFER;
+
+		user_protocol = of_get_property(dn, "dsa-tag-protocol", NULL);
+		return dsa_port_parse_cpu(dp, master, user_protocol);
+	}
+
+	if (link)
+		return dsa_port_parse_dsa(dp);
+
+	return dsa_port_parse_user(dp, name);
+}
+
+static int dsa_switch_parse_ports_of(struct dsa_switch *ds,
+				     struct device_node *dn)
+{
+	struct device_node *ports, *port;
+	struct dsa_port *dp;
+	int err = 0;
+	u32 reg;
+
+	ports = of_get_child_by_name(dn, "ports");
+	if (!ports) {
+		/* The second possibility is "ethernet-ports" */
+		ports = of_get_child_by_name(dn, "ethernet-ports");
+		if (!ports) {
+			dev_err(ds->dev, "no ports child node found\n");
+			return -EINVAL;
+		}
+	}
+
+	for_each_available_child_of_node(ports, port) {
+		err = of_property_read_u32(port, "reg", &reg);
+		if (err) {
+			of_node_put(port);
+			goto out_put_node;
+		}
+
+		if (reg >= ds->num_ports) {
+			dev_err(ds->dev, "port %pOF index %u exceeds num_ports (%u)\n",
+				port, reg, ds->num_ports);
+			of_node_put(port);
+			err = -EINVAL;
+			goto out_put_node;
+		}
+
+		dp = dsa_to_port(ds, reg);
+
+		err = dsa_port_parse_of(dp, port);
+		if (err) {
+			of_node_put(port);
+			goto out_put_node;
+		}
+	}
+
+out_put_node:
+	of_node_put(ports);
+	return err;
+}
+
+static int dsa_switch_parse_member_of(struct dsa_switch *ds,
+				      struct device_node *dn)
+{
+	u32 m[2] = { 0, 0 };
+	int sz;
+
+	/* Don't error out if this optional property isn't found */
+	sz = of_property_read_variable_u32_array(dn, "dsa,member", m, 2, 2);
+	if (sz < 0 && sz != -EINVAL)
+		return sz;
+
+	ds->index = m[1];
+
+	ds->dst = dsa_tree_touch(m[0]);
+	if (!ds->dst)
+		return -ENOMEM;
+
+	if (dsa_switch_find(ds->dst->index, ds->index)) {
+		dev_err(ds->dev,
+			"A DSA switch with index %d already exists in tree %d\n",
+			ds->index, ds->dst->index);
+		return -EEXIST;
+	}
+
+	if (ds->dst->last_switch < ds->index)
+		ds->dst->last_switch = ds->index;
+
+	return 0;
+}
+
+static int dsa_switch_touch_ports(struct dsa_switch *ds)
+{
+	struct dsa_port *dp;
+	int port;
+
+	for (port = 0; port < ds->num_ports; port++) {
+		dp = dsa_port_touch(ds, port);
+		if (!dp)
+			return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static int dsa_switch_parse_of(struct dsa_switch *ds, struct device_node *dn)
+{
+	int err;
+
+	err = dsa_switch_parse_member_of(ds, dn);
+	if (err)
+		return err;
+
+	err = dsa_switch_touch_ports(ds);
+	if (err)
+		return err;
+
+	return dsa_switch_parse_ports_of(ds, dn);
+}
+
+static int dsa_port_parse(struct dsa_port *dp, const char *name,
+			  struct device *dev)
+{
+	if (!strcmp(name, "cpu")) {
+		struct net_device *master;
+
+		master = dsa_dev_to_net_device(dev);
+		if (!master)
+			return -EPROBE_DEFER;
+
+		dev_put(master);
+
+		return dsa_port_parse_cpu(dp, master, NULL);
+	}
+
+	if (!strcmp(name, "dsa"))
+		return dsa_port_parse_dsa(dp);
+
+	return dsa_port_parse_user(dp, name);
+}
+
+static int dsa_switch_parse_ports(struct dsa_switch *ds,
+				  struct dsa_chip_data *cd)
+{
+	bool valid_name_found = false;
+	struct dsa_port *dp;
+	struct device *dev;
+	const char *name;
+	unsigned int i;
+	int err;
+
+	for (i = 0; i < DSA_MAX_PORTS; i++) {
+		name = cd->port_names[i];
+		dev = cd->netdev[i];
+		dp = dsa_to_port(ds, i);
+
+		if (!name)
+			continue;
+
+		err = dsa_port_parse(dp, name, dev);
+		if (err)
+			return err;
+
+		valid_name_found = true;
+	}
+
+	if (!valid_name_found && i == DSA_MAX_PORTS)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int dsa_switch_parse(struct dsa_switch *ds, struct dsa_chip_data *cd)
+{
+	int err;
+
+	ds->cd = cd;
+
+	/* We don't support interconnected switches nor multiple trees via
+	 * platform data, so this is the unique switch of the tree.
+	 */
+	ds->index = 0;
+	ds->dst = dsa_tree_touch(0);
+	if (!ds->dst)
+		return -ENOMEM;
+
+	err = dsa_switch_touch_ports(ds);
+	if (err)
+		return err;
+
+	return dsa_switch_parse_ports(ds, cd);
+}
+
+static void dsa_switch_release_ports(struct dsa_switch *ds)
+{
+	struct dsa_port *dp, *next;
+
+	dsa_switch_for_each_port_safe(dp, next, ds) {
+		WARN_ON(!list_empty(&dp->fdbs));
+		WARN_ON(!list_empty(&dp->mdbs));
+		WARN_ON(!list_empty(&dp->vlans));
+		list_del(&dp->list);
+		kfree(dp);
+	}
+}
+
+static int dsa_switch_probe(struct dsa_switch *ds)
+{
+	struct dsa_switch_tree *dst;
+	struct dsa_chip_data *pdata;
+	struct device_node *np;
+	int err;
+
+	if (!ds->dev)
+		return -ENODEV;
+
+	pdata = ds->dev->platform_data;
+	np = ds->dev->of_node;
+
+	if (!ds->num_ports)
+		return -EINVAL;
+
+	if (np) {
+		err = dsa_switch_parse_of(ds, np);
+		if (err)
+			dsa_switch_release_ports(ds);
+	} else if (pdata) {
+		err = dsa_switch_parse(ds, pdata);
+		if (err)
+			dsa_switch_release_ports(ds);
+	} else {
+		err = -ENODEV;
+	}
+
+	if (err)
+		return err;
+
+	dst = ds->dst;
+	dsa_tree_get(dst);
+	err = dsa_tree_setup(dst);
+	if (err) {
+		dsa_switch_release_ports(ds);
+		dsa_tree_put(dst);
+	}
+
+	return err;
+}
+
+int dsa_register_switch(struct dsa_switch *ds)
+{
+	int err;
+
+	mutex_lock(&dsa2_mutex);
+	err = dsa_switch_probe(ds);
+	dsa_tree_put(ds->dst);
+	mutex_unlock(&dsa2_mutex);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(dsa_register_switch);
+
+static void dsa_switch_remove(struct dsa_switch *ds)
+{
+	struct dsa_switch_tree *dst = ds->dst;
+
+	dsa_tree_teardown(dst);
+	dsa_switch_release_ports(ds);
+	dsa_tree_put(dst);
+}
+
+void dsa_unregister_switch(struct dsa_switch *ds)
+{
+	mutex_lock(&dsa2_mutex);
+	dsa_switch_remove(ds);
+	mutex_unlock(&dsa2_mutex);
+}
+EXPORT_SYMBOL_GPL(dsa_unregister_switch);
+
+/* If the DSA master chooses to unregister its net_device on .shutdown, DSA is
+ * blocking that operation from completion, due to the dev_hold taken inside
+ * netdev_upper_dev_link. Unlink the DSA slave interfaces from being uppers of
+ * the DSA master, so that the system can reboot successfully.
+ */
+void dsa_switch_shutdown(struct dsa_switch *ds)
+{
+	struct net_device *master, *slave_dev;
+	struct dsa_port *dp;
+
+	mutex_lock(&dsa2_mutex);
+
+	if (!ds->setup)
+		goto out;
+
+	rtnl_lock();
+
+	dsa_switch_for_each_user_port(dp, ds) {
+		master = dsa_port_to_master(dp);
+		slave_dev = dp->slave;
+
+		netdev_upper_dev_unlink(master, slave_dev);
+	}
+
+	/* Disconnect from further netdevice notifiers on the master,
+	 * since netdev_uses_dsa() will now return false.
+	 */
+	dsa_switch_for_each_cpu_port(dp, ds)
+		dp->master->dsa_ptr = NULL;
+
+	rtnl_unlock();
+out:
+	mutex_unlock(&dsa2_mutex);
+}
+EXPORT_SYMBOL_GPL(dsa_switch_shutdown);
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
new file mode 100644
index 000000000..71e9707d1
--- /dev/null
+++ b/net/dsa/dsa_priv.h
@@ -0,0 +1,588 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * net/dsa/dsa_priv.h - Hardware switch handling
+ * Copyright (c) 2008-2009 Marvell Semiconductor
+ */
+
+#ifndef __DSA_PRIV_H
+#define __DSA_PRIV_H
+
+#include <linux/if_bridge.h>
+#include <linux/if_vlan.h>
+#include <linux/phy.h>
+#include <linux/netdevice.h>
+#include <linux/netpoll.h>
+#include <net/dsa.h>
+#include <net/gro_cells.h>
+
+#define DSA_MAX_NUM_OFFLOADING_BRIDGES		BITS_PER_LONG
+
+enum {
+	DSA_NOTIFIER_AGEING_TIME,
+	DSA_NOTIFIER_BRIDGE_JOIN,
+	DSA_NOTIFIER_BRIDGE_LEAVE,
+	DSA_NOTIFIER_FDB_ADD,
+	DSA_NOTIFIER_FDB_DEL,
+	DSA_NOTIFIER_HOST_FDB_ADD,
+	DSA_NOTIFIER_HOST_FDB_DEL,
+	DSA_NOTIFIER_LAG_FDB_ADD,
+	DSA_NOTIFIER_LAG_FDB_DEL,
+	DSA_NOTIFIER_LAG_CHANGE,
+	DSA_NOTIFIER_LAG_JOIN,
+	DSA_NOTIFIER_LAG_LEAVE,
+	DSA_NOTIFIER_MDB_ADD,
+	DSA_NOTIFIER_MDB_DEL,
+	DSA_NOTIFIER_HOST_MDB_ADD,
+	DSA_NOTIFIER_HOST_MDB_DEL,
+	DSA_NOTIFIER_VLAN_ADD,
+	DSA_NOTIFIER_VLAN_DEL,
+	DSA_NOTIFIER_HOST_VLAN_ADD,
+	DSA_NOTIFIER_HOST_VLAN_DEL,
+	DSA_NOTIFIER_MTU,
+	DSA_NOTIFIER_TAG_PROTO,
+	DSA_NOTIFIER_TAG_PROTO_CONNECT,
+	DSA_NOTIFIER_TAG_PROTO_DISCONNECT,
+	DSA_NOTIFIER_TAG_8021Q_VLAN_ADD,
+	DSA_NOTIFIER_TAG_8021Q_VLAN_DEL,
+	DSA_NOTIFIER_MASTER_STATE_CHANGE,
+};
+
+/* DSA_NOTIFIER_AGEING_TIME */
+struct dsa_notifier_ageing_time_info {
+	unsigned int ageing_time;
+};
+
+/* DSA_NOTIFIER_BRIDGE_* */
+struct dsa_notifier_bridge_info {
+	const struct dsa_port *dp;
+	struct dsa_bridge bridge;
+	bool tx_fwd_offload;
+	struct netlink_ext_ack *extack;
+};
+
+/* DSA_NOTIFIER_FDB_* */
+struct dsa_notifier_fdb_info {
+	const struct dsa_port *dp;
+	const unsigned char *addr;
+	u16 vid;
+	struct dsa_db db;
+};
+
+/* DSA_NOTIFIER_LAG_FDB_* */
+struct dsa_notifier_lag_fdb_info {
+	struct dsa_lag *lag;
+	const unsigned char *addr;
+	u16 vid;
+	struct dsa_db db;
+};
+
+/* DSA_NOTIFIER_MDB_* */
+struct dsa_notifier_mdb_info {
+	const struct dsa_port *dp;
+	const struct switchdev_obj_port_mdb *mdb;
+	struct dsa_db db;
+};
+
+/* DSA_NOTIFIER_LAG_* */
+struct dsa_notifier_lag_info {
+	const struct dsa_port *dp;
+	struct dsa_lag lag;
+	struct netdev_lag_upper_info *info;
+	struct netlink_ext_ack *extack;
+};
+
+/* DSA_NOTIFIER_VLAN_* */
+struct dsa_notifier_vlan_info {
+	const struct dsa_port *dp;
+	const struct switchdev_obj_port_vlan *vlan;
+	struct netlink_ext_ack *extack;
+};
+
+/* DSA_NOTIFIER_MTU */
+struct dsa_notifier_mtu_info {
+	const struct dsa_port *dp;
+	int mtu;
+};
+
+/* DSA_NOTIFIER_TAG_PROTO_* */
+struct dsa_notifier_tag_proto_info {
+	const struct dsa_device_ops *tag_ops;
+};
+
+/* DSA_NOTIFIER_TAG_8021Q_VLAN_* */
+struct dsa_notifier_tag_8021q_vlan_info {
+	const struct dsa_port *dp;
+	u16 vid;
+};
+
+/* DSA_NOTIFIER_MASTER_STATE_CHANGE */
+struct dsa_notifier_master_state_info {
+	const struct net_device *master;
+	bool operational;
+};
+
+struct dsa_switchdev_event_work {
+	struct net_device *dev;
+	struct net_device *orig_dev;
+	struct work_struct work;
+	unsigned long event;
+	/* Specific for SWITCHDEV_FDB_ADD_TO_DEVICE and
+	 * SWITCHDEV_FDB_DEL_TO_DEVICE
+	 */
+	unsigned char addr[ETH_ALEN];
+	u16 vid;
+	bool host_addr;
+};
+
+enum dsa_standalone_event {
+	DSA_UC_ADD,
+	DSA_UC_DEL,
+	DSA_MC_ADD,
+	DSA_MC_DEL,
+};
+
+struct dsa_standalone_event_work {
+	struct work_struct work;
+	struct net_device *dev;
+	enum dsa_standalone_event event;
+	unsigned char addr[ETH_ALEN];
+	u16 vid;
+};
+
+struct dsa_slave_priv {
+	/* Copy of CPU port xmit for faster access in slave transmit hot path */
+	struct sk_buff *	(*xmit)(struct sk_buff *skb,
+					struct net_device *dev);
+
+	struct gro_cells	gcells;
+
+	/* DSA port data, such as switch, port index, etc. */
+	struct dsa_port		*dp;
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	struct netpoll		*netpoll;
+#endif
+
+	/* TC context */
+	struct list_head	mall_tc_list;
+};
+
+/* dsa.c */
+const struct dsa_device_ops *dsa_tag_driver_get(int tag_protocol);
+void dsa_tag_driver_put(const struct dsa_device_ops *ops);
+const struct dsa_device_ops *dsa_find_tagger_by_name(const char *buf);
+
+bool dsa_db_equal(const struct dsa_db *a, const struct dsa_db *b);
+
+bool dsa_schedule_work(struct work_struct *work);
+const char *dsa_tag_protocol_to_str(const struct dsa_device_ops *ops);
+
+static inline int dsa_tag_protocol_overhead(const struct dsa_device_ops *ops)
+{
+	return ops->needed_headroom + ops->needed_tailroom;
+}
+
+/* master.c */
+int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp);
+void dsa_master_teardown(struct net_device *dev);
+int dsa_master_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp,
+			 struct netdev_lag_upper_info *uinfo,
+			 struct netlink_ext_ack *extack);
+void dsa_master_lag_teardown(struct net_device *lag_dev,
+			     struct dsa_port *cpu_dp);
+
+static inline struct net_device *dsa_master_find_slave(struct net_device *dev,
+						       int device, int port)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	struct dsa_switch_tree *dst = cpu_dp->dst;
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dp->ds->index == device && dp->index == port &&
+		    dp->type == DSA_PORT_TYPE_USER)
+			return dp->slave;
+
+	return NULL;
+}
+
+/* netlink.c */
+extern struct rtnl_link_ops dsa_link_ops __read_mostly;
+
+/* port.c */
+bool dsa_port_supports_hwtstamp(struct dsa_port *dp, struct ifreq *ifr);
+void dsa_port_set_tag_protocol(struct dsa_port *cpu_dp,
+			       const struct dsa_device_ops *tag_ops);
+int dsa_port_set_state(struct dsa_port *dp, u8 state, bool do_fast_age);
+int dsa_port_set_mst_state(struct dsa_port *dp,
+			   const struct switchdev_mst_state *state,
+			   struct netlink_ext_ack *extack);
+int dsa_port_enable_rt(struct dsa_port *dp, struct phy_device *phy);
+int dsa_port_enable(struct dsa_port *dp, struct phy_device *phy);
+void dsa_port_disable_rt(struct dsa_port *dp);
+void dsa_port_disable(struct dsa_port *dp);
+int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br,
+			 struct netlink_ext_ack *extack);
+void dsa_port_pre_bridge_leave(struct dsa_port *dp, struct net_device *br);
+void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br);
+int dsa_port_lag_change(struct dsa_port *dp,
+			struct netdev_lag_lower_state_info *linfo);
+int dsa_port_lag_join(struct dsa_port *dp, struct net_device *lag_dev,
+		      struct netdev_lag_upper_info *uinfo,
+		      struct netlink_ext_ack *extack);
+void dsa_port_pre_lag_leave(struct dsa_port *dp, struct net_device *lag_dev);
+void dsa_port_lag_leave(struct dsa_port *dp, struct net_device *lag_dev);
+int dsa_port_vlan_filtering(struct dsa_port *dp, bool vlan_filtering,
+			    struct netlink_ext_ack *extack);
+bool dsa_port_skip_vlan_configuration(struct dsa_port *dp);
+int dsa_port_ageing_time(struct dsa_port *dp, clock_t ageing_clock);
+int dsa_port_mst_enable(struct dsa_port *dp, bool on,
+			struct netlink_ext_ack *extack);
+int dsa_port_vlan_msti(struct dsa_port *dp,
+		       const struct switchdev_vlan_msti *msti);
+int dsa_port_mtu_change(struct dsa_port *dp, int new_mtu);
+int dsa_port_fdb_add(struct dsa_port *dp, const unsigned char *addr,
+		     u16 vid);
+int dsa_port_fdb_del(struct dsa_port *dp, const unsigned char *addr,
+		     u16 vid);
+int dsa_port_standalone_host_fdb_add(struct dsa_port *dp,
+				     const unsigned char *addr, u16 vid);
+int dsa_port_standalone_host_fdb_del(struct dsa_port *dp,
+				     const unsigned char *addr, u16 vid);
+int dsa_port_bridge_host_fdb_add(struct dsa_port *dp, const unsigned char *addr,
+				 u16 vid);
+int dsa_port_bridge_host_fdb_del(struct dsa_port *dp, const unsigned char *addr,
+				 u16 vid);
+int dsa_port_lag_fdb_add(struct dsa_port *dp, const unsigned char *addr,
+			 u16 vid);
+int dsa_port_lag_fdb_del(struct dsa_port *dp, const unsigned char *addr,
+			 u16 vid);
+int dsa_port_fdb_dump(struct dsa_port *dp, dsa_fdb_dump_cb_t *cb, void *data);
+int dsa_port_mdb_add(const struct dsa_port *dp,
+		     const struct switchdev_obj_port_mdb *mdb);
+int dsa_port_mdb_del(const struct dsa_port *dp,
+		     const struct switchdev_obj_port_mdb *mdb);
+int dsa_port_standalone_host_mdb_add(const struct dsa_port *dp,
+				     const struct switchdev_obj_port_mdb *mdb);
+int dsa_port_standalone_host_mdb_del(const struct dsa_port *dp,
+				     const struct switchdev_obj_port_mdb *mdb);
+int dsa_port_bridge_host_mdb_add(const struct dsa_port *dp,
+				 const struct switchdev_obj_port_mdb *mdb);
+int dsa_port_bridge_host_mdb_del(const struct dsa_port *dp,
+				 const struct switchdev_obj_port_mdb *mdb);
+int dsa_port_pre_bridge_flags(const struct dsa_port *dp,
+			      struct switchdev_brport_flags flags,
+			      struct netlink_ext_ack *extack);
+int dsa_port_bridge_flags(struct dsa_port *dp,
+			  struct switchdev_brport_flags flags,
+			  struct netlink_ext_ack *extack);
+int dsa_port_vlan_add(struct dsa_port *dp,
+		      const struct switchdev_obj_port_vlan *vlan,
+		      struct netlink_ext_ack *extack);
+int dsa_port_vlan_del(struct dsa_port *dp,
+		      const struct switchdev_obj_port_vlan *vlan);
+int dsa_port_host_vlan_add(struct dsa_port *dp,
+			   const struct switchdev_obj_port_vlan *vlan,
+			   struct netlink_ext_ack *extack);
+int dsa_port_host_vlan_del(struct dsa_port *dp,
+			   const struct switchdev_obj_port_vlan *vlan);
+int dsa_port_mrp_add(const struct dsa_port *dp,
+		     const struct switchdev_obj_mrp *mrp);
+int dsa_port_mrp_del(const struct dsa_port *dp,
+		     const struct switchdev_obj_mrp *mrp);
+int dsa_port_mrp_add_ring_role(const struct dsa_port *dp,
+			       const struct switchdev_obj_ring_role_mrp *mrp);
+int dsa_port_mrp_del_ring_role(const struct dsa_port *dp,
+			       const struct switchdev_obj_ring_role_mrp *mrp);
+int dsa_port_phylink_create(struct dsa_port *dp);
+void dsa_port_phylink_destroy(struct dsa_port *dp);
+int dsa_shared_port_link_register_of(struct dsa_port *dp);
+void dsa_shared_port_link_unregister_of(struct dsa_port *dp);
+int dsa_port_hsr_join(struct dsa_port *dp, struct net_device *hsr);
+void dsa_port_hsr_leave(struct dsa_port *dp, struct net_device *hsr);
+int dsa_port_tag_8021q_vlan_add(struct dsa_port *dp, u16 vid, bool broadcast);
+void dsa_port_tag_8021q_vlan_del(struct dsa_port *dp, u16 vid, bool broadcast);
+void dsa_port_set_host_flood(struct dsa_port *dp, bool uc, bool mc);
+int dsa_port_change_master(struct dsa_port *dp, struct net_device *master,
+			   struct netlink_ext_ack *extack);
+
+/* slave.c */
+extern const struct dsa_device_ops notag_netdev_ops;
+extern struct notifier_block dsa_slave_switchdev_notifier;
+extern struct notifier_block dsa_slave_switchdev_blocking_notifier;
+
+void dsa_slave_mii_bus_init(struct dsa_switch *ds);
+int dsa_slave_create(struct dsa_port *dp);
+void dsa_slave_destroy(struct net_device *slave_dev);
+int dsa_slave_suspend(struct net_device *slave_dev);
+int dsa_slave_resume(struct net_device *slave_dev);
+int dsa_slave_register_notifier(void);
+void dsa_slave_unregister_notifier(void);
+void dsa_slave_sync_ha(struct net_device *dev);
+void dsa_slave_unsync_ha(struct net_device *dev);
+void dsa_slave_setup_tagger(struct net_device *slave);
+int dsa_slave_change_mtu(struct net_device *dev, int new_mtu);
+int dsa_slave_change_master(struct net_device *dev, struct net_device *master,
+			    struct netlink_ext_ack *extack);
+int dsa_slave_manage_vlan_filtering(struct net_device *dev,
+				    bool vlan_filtering);
+
+static inline struct dsa_port *dsa_slave_to_port(const struct net_device *dev)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+
+	return p->dp;
+}
+
+static inline struct net_device *
+dsa_slave_to_master(const struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return dsa_port_to_master(dp);
+}
+
+/* If under a bridge with vlan_filtering=0, make sure to send pvid-tagged
+ * frames as untagged, since the bridge will not untag them.
+ */
+static inline struct sk_buff *dsa_untag_bridge_pvid(struct sk_buff *skb)
+{
+	struct dsa_port *dp = dsa_slave_to_port(skb->dev);
+	struct net_device *br = dsa_port_bridge_dev_get(dp);
+	struct net_device *dev = skb->dev;
+	struct net_device *upper_dev;
+	u16 vid, pvid, proto;
+	int err;
+
+	if (!br || br_vlan_enabled(br))
+		return skb;
+
+	err = br_vlan_get_proto(br, &proto);
+	if (err)
+		return skb;
+
+	/* Move VLAN tag from data to hwaccel */
+	if (!skb_vlan_tag_present(skb) && skb->protocol == htons(proto)) {
+		skb = skb_vlan_untag(skb);
+		if (!skb)
+			return NULL;
+	}
+
+	if (!skb_vlan_tag_present(skb))
+		return skb;
+
+	vid = skb_vlan_tag_get_id(skb);
+
+	/* We already run under an RCU read-side critical section since
+	 * we are called from netif_receive_skb_list_internal().
+	 */
+	err = br_vlan_get_pvid_rcu(dev, &pvid);
+	if (err)
+		return skb;
+
+	if (vid != pvid)
+		return skb;
+
+	/* The sad part about attempting to untag from DSA is that we
+	 * don't know, unless we check, if the skb will end up in
+	 * the bridge's data path - br_allowed_ingress() - or not.
+	 * For example, there might be an 8021q upper for the
+	 * default_pvid of the bridge, which will steal VLAN-tagged traffic
+	 * from the bridge's data path. This is a configuration that DSA
+	 * supports because vlan_filtering is 0. In that case, we should
+	 * definitely keep the tag, to make sure it keeps working.
+	 */
+	upper_dev = __vlan_find_dev_deep_rcu(br, htons(proto), vid);
+	if (upper_dev)
+		return skb;
+
+	__vlan_hwaccel_clear_tag(skb);
+
+	return skb;
+}
+
+/* For switches without hardware support for DSA tagging to be able
+ * to support termination through the bridge.
+ */
+static inline struct net_device *
+dsa_find_designated_bridge_port_by_vid(struct net_device *master, u16 vid)
+{
+	struct dsa_port *cpu_dp = master->dsa_ptr;
+	struct dsa_switch_tree *dst = cpu_dp->dst;
+	struct bridge_vlan_info vinfo;
+	struct net_device *slave;
+	struct dsa_port *dp;
+	int err;
+
+	list_for_each_entry(dp, &dst->ports, list) {
+		if (dp->type != DSA_PORT_TYPE_USER)
+			continue;
+
+		if (!dp->bridge)
+			continue;
+
+		if (dp->stp_state != BR_STATE_LEARNING &&
+		    dp->stp_state != BR_STATE_FORWARDING)
+			continue;
+
+		/* Since the bridge might learn this packet, keep the CPU port
+		 * affinity with the port that will be used for the reply on
+		 * xmit.
+		 */
+		if (dp->cpu_dp != cpu_dp)
+			continue;
+
+		slave = dp->slave;
+
+		err = br_vlan_get_info_rcu(slave, vid, &vinfo);
+		if (err)
+			continue;
+
+		return slave;
+	}
+
+	return NULL;
+}
+
+/* If the ingress port offloads the bridge, we mark the frame as autonomously
+ * forwarded by hardware, so the software bridge doesn't forward in twice, back
+ * to us, because we already did. However, if we're in fallback mode and we do
+ * software bridging, we are not offloading it, therefore the dp->bridge
+ * pointer is not populated, and flooding needs to be done by software (we are
+ * effectively operating in standalone ports mode).
+ */
+static inline void dsa_default_offload_fwd_mark(struct sk_buff *skb)
+{
+	struct dsa_port *dp = dsa_slave_to_port(skb->dev);
+
+	skb->offload_fwd_mark = !!(dp->bridge);
+}
+
+/* Helper for removing DSA header tags from packets in the RX path.
+ * Must not be called before skb_pull(len).
+ *                                                                 skb->data
+ *                                                                         |
+ *                                                                         v
+ * |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
+ * +-----------------------+-----------------------+---------------+-------+
+ * |    Destination MAC    |      Source MAC       |  DSA header   | EType |
+ * +-----------------------+-----------------------+---------------+-------+
+ *                                                 |               |
+ * <----- len ----->                               <----- len ----->
+ *                 |
+ *       >>>>>>>   v
+ *       >>>>>>>   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
+ *       >>>>>>>   +-----------------------+-----------------------+-------+
+ *       >>>>>>>   |    Destination MAC    |      Source MAC       | EType |
+ *                 +-----------------------+-----------------------+-------+
+ *                                                                         ^
+ *                                                                         |
+ *                                                                 skb->data
+ */
+static inline void dsa_strip_etype_header(struct sk_buff *skb, int len)
+{
+	memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - len, 2 * ETH_ALEN);
+}
+
+/* Helper for creating space for DSA header tags in TX path packets.
+ * Must not be called before skb_push(len).
+ *
+ * Before:
+ *
+ *       <<<<<<<   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
+ * ^     <<<<<<<   +-----------------------+-----------------------+-------+
+ * |     <<<<<<<   |    Destination MAC    |      Source MAC       | EType |
+ * |               +-----------------------+-----------------------+-------+
+ * <----- len ----->
+ * |
+ * |
+ * skb->data
+ *
+ * After:
+ *
+ * |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
+ * +-----------------------+-----------------------+---------------+-------+
+ * |    Destination MAC    |      Source MAC       |  DSA header   | EType |
+ * +-----------------------+-----------------------+---------------+-------+
+ * ^                                               |               |
+ * |                                               <----- len ----->
+ * skb->data
+ */
+static inline void dsa_alloc_etype_header(struct sk_buff *skb, int len)
+{
+	memmove(skb->data, skb->data + len, 2 * ETH_ALEN);
+}
+
+/* On RX, eth_type_trans() on the DSA master pulls ETH_HLEN bytes starting from
+ * skb_mac_header(skb), which leaves skb->data pointing at the first byte after
+ * what the DSA master perceives as the EtherType (the beginning of the L3
+ * protocol). Since DSA EtherType header taggers treat the EtherType as part of
+ * the DSA tag itself, and the EtherType is 2 bytes in length, the DSA header
+ * is located 2 bytes behind skb->data. Note that EtherType in this context
+ * means the first 2 bytes of the DSA header, not the encapsulated EtherType
+ * that will become visible after the DSA header is stripped.
+ */
+static inline void *dsa_etype_header_pos_rx(struct sk_buff *skb)
+{
+	return skb->data - 2;
+}
+
+/* On TX, skb->data points to skb_mac_header(skb), which means that EtherType
+ * header taggers start exactly where the EtherType is (the EtherType is
+ * treated as part of the DSA header).
+ */
+static inline void *dsa_etype_header_pos_tx(struct sk_buff *skb)
+{
+	return skb->data + 2 * ETH_ALEN;
+}
+
+/* switch.c */
+int dsa_switch_register_notifier(struct dsa_switch *ds);
+void dsa_switch_unregister_notifier(struct dsa_switch *ds);
+
+static inline bool dsa_switch_supports_uc_filtering(struct dsa_switch *ds)
+{
+	return ds->ops->port_fdb_add && ds->ops->port_fdb_del &&
+	       ds->fdb_isolation && !ds->vlan_filtering_is_global &&
+	       !ds->needs_standalone_vlan_filtering;
+}
+
+static inline bool dsa_switch_supports_mc_filtering(struct dsa_switch *ds)
+{
+	return ds->ops->port_mdb_add && ds->ops->port_mdb_del &&
+	       ds->fdb_isolation && !ds->vlan_filtering_is_global &&
+	       !ds->needs_standalone_vlan_filtering;
+}
+
+/* dsa2.c */
+void dsa_lag_map(struct dsa_switch_tree *dst, struct dsa_lag *lag);
+void dsa_lag_unmap(struct dsa_switch_tree *dst, struct dsa_lag *lag);
+struct dsa_lag *dsa_tree_lag_find(struct dsa_switch_tree *dst,
+				  const struct net_device *lag_dev);
+struct net_device *dsa_tree_find_first_master(struct dsa_switch_tree *dst);
+int dsa_tree_notify(struct dsa_switch_tree *dst, unsigned long e, void *v);
+int dsa_broadcast(unsigned long e, void *v);
+int dsa_tree_change_tag_proto(struct dsa_switch_tree *dst,
+			      const struct dsa_device_ops *tag_ops,
+			      const struct dsa_device_ops *old_tag_ops);
+void dsa_tree_master_admin_state_change(struct dsa_switch_tree *dst,
+					struct net_device *master,
+					bool up);
+void dsa_tree_master_oper_state_change(struct dsa_switch_tree *dst,
+				       struct net_device *master,
+				       bool up);
+unsigned int dsa_bridge_num_get(const struct net_device *bridge_dev, int max);
+void dsa_bridge_num_put(const struct net_device *bridge_dev,
+			unsigned int bridge_num);
+struct dsa_bridge *dsa_tree_bridge_find(struct dsa_switch_tree *dst,
+					const struct net_device *br);
+
+/* tag_8021q.c */
+int dsa_switch_tag_8021q_vlan_add(struct dsa_switch *ds,
+				  struct dsa_notifier_tag_8021q_vlan_info *info);
+int dsa_switch_tag_8021q_vlan_del(struct dsa_switch *ds,
+				  struct dsa_notifier_tag_8021q_vlan_info *info);
+
+extern struct list_head dsa_tree_list;
+
+#endif
diff --git a/net/dsa/master.c b/net/dsa/master.c
new file mode 100644
index 000000000..421de1665
--- /dev/null
+++ b/net/dsa/master.c
@@ -0,0 +1,478 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Handling of a master device, switching frames via its switch fabric CPU port
+ *
+ * Copyright (c) 2017 Savoir-faire Linux Inc.
+ *	Vivien Didelot <vivien.didelot@savoirfairelinux.com>
+ */
+
+#include "dsa_priv.h"
+
+static int dsa_master_get_regs_len(struct net_device *dev)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	int port = cpu_dp->index;
+	int ret = 0;
+	int len;
+
+	if (ops->get_regs_len) {
+		len = ops->get_regs_len(dev);
+		if (len < 0)
+			return len;
+		ret += len;
+	}
+
+	ret += sizeof(struct ethtool_drvinfo);
+	ret += sizeof(struct ethtool_regs);
+
+	if (ds->ops->get_regs_len) {
+		len = ds->ops->get_regs_len(ds, port);
+		if (len < 0)
+			return len;
+		ret += len;
+	}
+
+	return ret;
+}
+
+static void dsa_master_get_regs(struct net_device *dev,
+				struct ethtool_regs *regs, void *data)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct ethtool_drvinfo *cpu_info;
+	struct ethtool_regs *cpu_regs;
+	int port = cpu_dp->index;
+	int len;
+
+	if (ops->get_regs_len && ops->get_regs) {
+		len = ops->get_regs_len(dev);
+		if (len < 0)
+			return;
+		regs->len = len;
+		ops->get_regs(dev, regs, data);
+		data += regs->len;
+	}
+
+	cpu_info = (struct ethtool_drvinfo *)data;
+	strscpy(cpu_info->driver, "dsa", sizeof(cpu_info->driver));
+	data += sizeof(*cpu_info);
+	cpu_regs = (struct ethtool_regs *)data;
+	data += sizeof(*cpu_regs);
+
+	if (ds->ops->get_regs_len && ds->ops->get_regs) {
+		len = ds->ops->get_regs_len(ds, port);
+		if (len < 0)
+			return;
+		cpu_regs->len = len;
+		ds->ops->get_regs(ds, port, cpu_regs, data);
+	}
+}
+
+static void dsa_master_get_ethtool_stats(struct net_device *dev,
+					 struct ethtool_stats *stats,
+					 uint64_t *data)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	int port = cpu_dp->index;
+	int count = 0;
+
+	if (ops->get_sset_count && ops->get_ethtool_stats) {
+		count = ops->get_sset_count(dev, ETH_SS_STATS);
+		ops->get_ethtool_stats(dev, stats, data);
+	}
+
+	if (ds->ops->get_ethtool_stats)
+		ds->ops->get_ethtool_stats(ds, port, data + count);
+}
+
+static void dsa_master_get_ethtool_phy_stats(struct net_device *dev,
+					     struct ethtool_stats *stats,
+					     uint64_t *data)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	int port = cpu_dp->index;
+	int count = 0;
+
+	if (dev->phydev && !ops->get_ethtool_phy_stats) {
+		count = phy_ethtool_get_sset_count(dev->phydev);
+		if (count >= 0)
+			phy_ethtool_get_stats(dev->phydev, stats, data);
+	} else if (ops->get_sset_count && ops->get_ethtool_phy_stats) {
+		count = ops->get_sset_count(dev, ETH_SS_PHY_STATS);
+		ops->get_ethtool_phy_stats(dev, stats, data);
+	}
+
+	if (count < 0)
+		count = 0;
+
+	if (ds->ops->get_ethtool_phy_stats)
+		ds->ops->get_ethtool_phy_stats(ds, port, data + count);
+}
+
+static int dsa_master_get_sset_count(struct net_device *dev, int sset)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	int count = 0;
+
+	if (sset == ETH_SS_PHY_STATS && dev->phydev &&
+	    !ops->get_ethtool_phy_stats)
+		count = phy_ethtool_get_sset_count(dev->phydev);
+	else if (ops->get_sset_count)
+		count = ops->get_sset_count(dev, sset);
+
+	if (count < 0)
+		count = 0;
+
+	if (ds->ops->get_sset_count)
+		count += ds->ops->get_sset_count(ds, cpu_dp->index, sset);
+
+	return count;
+}
+
+static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset,
+				   uint8_t *data)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	int port = cpu_dp->index;
+	int len = ETH_GSTRING_LEN;
+	int mcount = 0, count, i;
+	uint8_t pfx[4];
+	uint8_t *ndata;
+
+	snprintf(pfx, sizeof(pfx), "p%.2d", port);
+	/* We do not want to be NULL-terminated, since this is a prefix */
+	pfx[sizeof(pfx) - 1] = '_';
+
+	if (stringset == ETH_SS_PHY_STATS && dev->phydev &&
+	    !ops->get_ethtool_phy_stats) {
+		mcount = phy_ethtool_get_sset_count(dev->phydev);
+		if (mcount < 0)
+			mcount = 0;
+		else
+			phy_ethtool_get_strings(dev->phydev, data);
+	} else if (ops->get_sset_count && ops->get_strings) {
+		mcount = ops->get_sset_count(dev, stringset);
+		if (mcount < 0)
+			mcount = 0;
+		ops->get_strings(dev, stringset, data);
+	}
+
+	if (ds->ops->get_strings) {
+		ndata = data + mcount * len;
+		/* This function copies ETH_GSTRINGS_LEN bytes, we will mangle
+		 * the output after to prepend our CPU port prefix we
+		 * constructed earlier
+		 */
+		ds->ops->get_strings(ds, port, stringset, ndata);
+		count = ds->ops->get_sset_count(ds, port, stringset);
+		if (count < 0)
+			return;
+		for (i = 0; i < count; i++) {
+			memmove(ndata + (i * len + sizeof(pfx)),
+				ndata + i * len, len - sizeof(pfx));
+			memcpy(ndata + i * len, pfx, sizeof(pfx));
+		}
+	}
+}
+
+static int dsa_master_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct dsa_switch_tree *dst;
+	int err = -EOPNOTSUPP;
+	struct dsa_port *dp;
+
+	dst = ds->dst;
+
+	switch (cmd) {
+	case SIOCGHWTSTAMP:
+	case SIOCSHWTSTAMP:
+		/* Deny PTP operations on master if there is at least one
+		 * switch in the tree that is PTP capable.
+		 */
+		list_for_each_entry(dp, &dst->ports, list)
+			if (dsa_port_supports_hwtstamp(dp, ifr))
+				return -EBUSY;
+		break;
+	}
+
+	if (dev->netdev_ops->ndo_eth_ioctl)
+		err = dev->netdev_ops->ndo_eth_ioctl(dev, ifr, cmd);
+
+	return err;
+}
+
+static const struct dsa_netdevice_ops dsa_netdev_ops = {
+	.ndo_eth_ioctl = dsa_master_ioctl,
+};
+
+static int dsa_master_ethtool_setup(struct net_device *dev)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct ethtool_ops *ops;
+
+	if (netif_is_lag_master(dev))
+		return 0;
+
+	ops = devm_kzalloc(ds->dev, sizeof(*ops), GFP_KERNEL);
+	if (!ops)
+		return -ENOMEM;
+
+	cpu_dp->orig_ethtool_ops = dev->ethtool_ops;
+	if (cpu_dp->orig_ethtool_ops)
+		memcpy(ops, cpu_dp->orig_ethtool_ops, sizeof(*ops));
+
+	ops->get_regs_len = dsa_master_get_regs_len;
+	ops->get_regs = dsa_master_get_regs;
+	ops->get_sset_count = dsa_master_get_sset_count;
+	ops->get_ethtool_stats = dsa_master_get_ethtool_stats;
+	ops->get_strings = dsa_master_get_strings;
+	ops->get_ethtool_phy_stats = dsa_master_get_ethtool_phy_stats;
+
+	dev->ethtool_ops = ops;
+
+	return 0;
+}
+
+static void dsa_master_ethtool_teardown(struct net_device *dev)
+{
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+
+	if (netif_is_lag_master(dev))
+		return;
+
+	dev->ethtool_ops = cpu_dp->orig_ethtool_ops;
+	cpu_dp->orig_ethtool_ops = NULL;
+}
+
+static void dsa_netdev_ops_set(struct net_device *dev,
+			       const struct dsa_netdevice_ops *ops)
+{
+	if (netif_is_lag_master(dev))
+		return;
+
+	dev->dsa_ptr->netdev_ops = ops;
+}
+
+/* Keep the master always promiscuous if the tagging protocol requires that
+ * (garbles MAC DA) or if it doesn't support unicast filtering, case in which
+ * it would revert to promiscuous mode as soon as we call dev_uc_add() on it
+ * anyway.
+ */
+static void dsa_master_set_promiscuity(struct net_device *dev, int inc)
+{
+	const struct dsa_device_ops *ops = dev->dsa_ptr->tag_ops;
+
+	if ((dev->priv_flags & IFF_UNICAST_FLT) && !ops->promisc_on_master)
+		return;
+
+	ASSERT_RTNL();
+
+	dev_set_promiscuity(dev, inc);
+}
+
+static ssize_t tagging_show(struct device *d, struct device_attribute *attr,
+			    char *buf)
+{
+	struct net_device *dev = to_net_dev(d);
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+
+	return sprintf(buf, "%s\n",
+		       dsa_tag_protocol_to_str(cpu_dp->tag_ops));
+}
+
+static ssize_t tagging_store(struct device *d, struct device_attribute *attr,
+			     const char *buf, size_t count)
+{
+	const struct dsa_device_ops *new_tag_ops, *old_tag_ops;
+	struct net_device *dev = to_net_dev(d);
+	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	int err;
+
+	old_tag_ops = cpu_dp->tag_ops;
+	new_tag_ops = dsa_find_tagger_by_name(buf);
+	/* Bad tagger name, or module is not loaded? */
+	if (IS_ERR(new_tag_ops))
+		return PTR_ERR(new_tag_ops);
+
+	if (new_tag_ops == old_tag_ops)
+		/* Drop the temporarily held duplicate reference, since
+		 * the DSA switch tree uses this tagger.
+		 */
+		goto out;
+
+	err = dsa_tree_change_tag_proto(cpu_dp->ds->dst, new_tag_ops,
+					old_tag_ops);
+	if (err) {
+		/* On failure the old tagger is restored, so we don't need the
+		 * driver for the new one.
+		 */
+		dsa_tag_driver_put(new_tag_ops);
+		return err;
+	}
+
+	/* On success we no longer need the module for the old tagging protocol
+	 */
+out:
+	dsa_tag_driver_put(old_tag_ops);
+	return count;
+}
+static DEVICE_ATTR_RW(tagging);
+
+static struct attribute *dsa_slave_attrs[] = {
+	&dev_attr_tagging.attr,
+	NULL
+};
+
+static const struct attribute_group dsa_group = {
+	.name	= "dsa",
+	.attrs	= dsa_slave_attrs,
+};
+
+static void dsa_master_reset_mtu(struct net_device *dev)
+{
+	int err;
+
+	err = dev_set_mtu(dev, ETH_DATA_LEN);
+	if (err)
+		netdev_dbg(dev,
+			   "Unable to reset MTU to exclude DSA overheads\n");
+}
+
+int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
+{
+	const struct dsa_device_ops *tag_ops = cpu_dp->tag_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct device_link *consumer_link;
+	int mtu, ret;
+
+	mtu = ETH_DATA_LEN + dsa_tag_protocol_overhead(tag_ops);
+
+	/* The DSA master must use SET_NETDEV_DEV for this to work. */
+	if (!netif_is_lag_master(dev)) {
+		consumer_link = device_link_add(ds->dev, dev->dev.parent,
+						DL_FLAG_AUTOREMOVE_CONSUMER);
+		if (!consumer_link)
+			netdev_err(dev,
+				   "Failed to create a device link to DSA switch %s\n",
+				   dev_name(ds->dev));
+	}
+
+	/* The switch driver may not implement ->port_change_mtu(), case in
+	 * which dsa_slave_change_mtu() will not update the master MTU either,
+	 * so we need to do that here.
+	 */
+	ret = dev_set_mtu(dev, mtu);
+	if (ret)
+		netdev_warn(dev, "error %d setting MTU to %d to include DSA overhead\n",
+			    ret, mtu);
+
+	/* If we use a tagging format that doesn't have an ethertype
+	 * field, make sure that all packets from this point on get
+	 * sent to the tag format's receive function.
+	 */
+	wmb();
+
+	dev->dsa_ptr = cpu_dp;
+
+	dsa_master_set_promiscuity(dev, 1);
+
+	ret = dsa_master_ethtool_setup(dev);
+	if (ret)
+		goto out_err_reset_promisc;
+
+	dsa_netdev_ops_set(dev, &dsa_netdev_ops);
+
+	ret = sysfs_create_group(&dev->dev.kobj, &dsa_group);
+	if (ret)
+		goto out_err_ndo_teardown;
+
+	return ret;
+
+out_err_ndo_teardown:
+	dsa_netdev_ops_set(dev, NULL);
+	dsa_master_ethtool_teardown(dev);
+out_err_reset_promisc:
+	dsa_master_set_promiscuity(dev, -1);
+	return ret;
+}
+
+void dsa_master_teardown(struct net_device *dev)
+{
+	sysfs_remove_group(&dev->dev.kobj, &dsa_group);
+	dsa_netdev_ops_set(dev, NULL);
+	dsa_master_ethtool_teardown(dev);
+	dsa_master_reset_mtu(dev);
+	dsa_master_set_promiscuity(dev, -1);
+
+	dev->dsa_ptr = NULL;
+
+	/* If we used a tagging format that doesn't have an ethertype
+	 * field, make sure that all packets from this point get sent
+	 * without the tag and go through the regular receive path.
+	 */
+	wmb();
+}
+
+int dsa_master_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp,
+			 struct netdev_lag_upper_info *uinfo,
+			 struct netlink_ext_ack *extack)
+{
+	bool master_setup = false;
+	int err;
+
+	if (!netdev_uses_dsa(lag_dev)) {
+		err = dsa_master_setup(lag_dev, cpu_dp);
+		if (err)
+			return err;
+
+		master_setup = true;
+	}
+
+	err = dsa_port_lag_join(cpu_dp, lag_dev, uinfo, extack);
+	if (err) {
+		if (extack && !extack->_msg)
+			NL_SET_ERR_MSG_MOD(extack,
+					   "CPU port failed to join LAG");
+		goto out_master_teardown;
+	}
+
+	return 0;
+
+out_master_teardown:
+	if (master_setup)
+		dsa_master_teardown(lag_dev);
+	return err;
+}
+
+/* Tear down a master if there isn't any other user port on it,
+ * optionally also destroying LAG information.
+ */
+void dsa_master_lag_teardown(struct net_device *lag_dev,
+			     struct dsa_port *cpu_dp)
+{
+	struct net_device *upper;
+	struct list_head *iter;
+
+	dsa_port_lag_leave(cpu_dp, lag_dev);
+
+	netdev_for_each_upper_dev_rcu(lag_dev, upper, iter)
+		if (dsa_slave_dev_check(upper))
+			return;
+
+	dsa_master_teardown(lag_dev);
+}
diff --git a/net/dsa/netlink.c b/net/dsa/netlink.c
new file mode 100644
index 000000000..ecf9ed1de
--- /dev/null
+++ b/net/dsa/netlink.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2022 NXP
+ */
+#include <linux/netdevice.h>
+#include <net/rtnetlink.h>
+
+#include "dsa_priv.h"
+
+static const struct nla_policy dsa_policy[IFLA_DSA_MAX + 1] = {
+	[IFLA_DSA_MASTER]	= { .type = NLA_U32 },
+};
+
+static int dsa_changelink(struct net_device *dev, struct nlattr *tb[],
+			  struct nlattr *data[],
+			  struct netlink_ext_ack *extack)
+{
+	int err;
+
+	if (!data)
+		return 0;
+
+	if (data[IFLA_DSA_MASTER]) {
+		u32 ifindex = nla_get_u32(data[IFLA_DSA_MASTER]);
+		struct net_device *master;
+
+		master = __dev_get_by_index(dev_net(dev), ifindex);
+		if (!master)
+			return -EINVAL;
+
+		err = dsa_slave_change_master(dev, master, extack);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static size_t dsa_get_size(const struct net_device *dev)
+{
+	return nla_total_size(sizeof(u32)) +	/* IFLA_DSA_MASTER  */
+	       0;
+}
+
+static int dsa_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+
+	if (nla_put_u32(skb, IFLA_DSA_MASTER, master->ifindex))
+		return -EMSGSIZE;
+
+	return 0;
+}
+
+struct rtnl_link_ops dsa_link_ops __read_mostly = {
+	.kind			= "dsa",
+	.priv_size		= sizeof(struct dsa_port),
+	.maxtype		= IFLA_DSA_MAX,
+	.policy			= dsa_policy,
+	.changelink		= dsa_changelink,
+	.get_size		= dsa_get_size,
+	.fill_info		= dsa_fill_info,
+	.netns_refund		= true,
+};
diff --git a/net/dsa/port.c b/net/dsa/port.c
new file mode 100644
index 000000000..750fe68d9
--- /dev/null
+++ b/net/dsa/port.c
@@ -0,0 +1,2083 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Handling of a single switch port
+ *
+ * Copyright (c) 2017 Savoir-faire Linux Inc.
+ *	Vivien Didelot <vivien.didelot@savoirfairelinux.com>
+ */
+
+#include <linux/if_bridge.h>
+#include <linux/netdevice.h>
+#include <linux/notifier.h>
+#include <linux/of_mdio.h>
+#include <linux/of_net.h>
+
+#include "dsa_priv.h"
+
+/**
+ * dsa_port_notify - Notify the switching fabric of changes to a port
+ * @dp: port on which change occurred
+ * @e: event, must be of type DSA_NOTIFIER_*
+ * @v: event-specific value.
+ *
+ * Notify all switches in the DSA tree that this port's switch belongs to,
+ * including this switch itself, of an event. Allows the other switches to
+ * reconfigure themselves for cross-chip operations. Can also be used to
+ * reconfigure ports without net_devices (CPU ports, DSA links) whenever
+ * a user port's state changes.
+ */
+static int dsa_port_notify(const struct dsa_port *dp, unsigned long e, void *v)
+{
+	return dsa_tree_notify(dp->ds->dst, e, v);
+}
+
+static void dsa_port_notify_bridge_fdb_flush(const struct dsa_port *dp, u16 vid)
+{
+	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
+	struct switchdev_notifier_fdb_info info = {
+		.vid = vid,
+	};
+
+	/* When the port becomes standalone it has already left the bridge.
+	 * Don't notify the bridge in that case.
+	 */
+	if (!brport_dev)
+		return;
+
+	call_switchdev_notifiers(SWITCHDEV_FDB_FLUSH_TO_BRIDGE,
+				 brport_dev, &info.info, NULL);
+}
+
+static void dsa_port_fast_age(const struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->port_fast_age)
+		return;
+
+	ds->ops->port_fast_age(ds, dp->index);
+
+	/* flush all VLANs */
+	dsa_port_notify_bridge_fdb_flush(dp, 0);
+}
+
+static int dsa_port_vlan_fast_age(const struct dsa_port *dp, u16 vid)
+{
+	struct dsa_switch *ds = dp->ds;
+	int err;
+
+	if (!ds->ops->port_vlan_fast_age)
+		return -EOPNOTSUPP;
+
+	err = ds->ops->port_vlan_fast_age(ds, dp->index, vid);
+
+	if (!err)
+		dsa_port_notify_bridge_fdb_flush(dp, vid);
+
+	return err;
+}
+
+static int dsa_port_msti_fast_age(const struct dsa_port *dp, u16 msti)
+{
+	DECLARE_BITMAP(vids, VLAN_N_VID) = { 0 };
+	int err, vid;
+
+	err = br_mst_get_info(dsa_port_bridge_dev_get(dp), msti, vids);
+	if (err)
+		return err;
+
+	for_each_set_bit(vid, vids, VLAN_N_VID) {
+		err = dsa_port_vlan_fast_age(dp, vid);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static bool dsa_port_can_configure_learning(struct dsa_port *dp)
+{
+	struct switchdev_brport_flags flags = {
+		.mask = BR_LEARNING,
+	};
+	struct dsa_switch *ds = dp->ds;
+	int err;
+
+	if (!ds->ops->port_bridge_flags || !ds->ops->port_pre_bridge_flags)
+		return false;
+
+	err = ds->ops->port_pre_bridge_flags(ds, dp->index, flags, NULL);
+	return !err;
+}
+
+bool dsa_port_supports_hwtstamp(struct dsa_port *dp, struct ifreq *ifr)
+{
+	struct dsa_switch *ds = dp->ds;
+	int err;
+
+	if (!ds->ops->port_hwtstamp_get || !ds->ops->port_hwtstamp_set)
+		return false;
+
+	/* "See through" shim implementations of the "get" method.
+	 * This will clobber the ifreq structure, but we will either return an
+	 * error, or the master will overwrite it with proper values.
+	 */
+	err = ds->ops->port_hwtstamp_get(ds, dp->index, ifr);
+	return err != -EOPNOTSUPP;
+}
+
+int dsa_port_set_state(struct dsa_port *dp, u8 state, bool do_fast_age)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+
+	if (!ds->ops->port_stp_state_set)
+		return -EOPNOTSUPP;
+
+	ds->ops->port_stp_state_set(ds, port, state);
+
+	if (!dsa_port_can_configure_learning(dp) ||
+	    (do_fast_age && dp->learning)) {
+		/* Fast age FDB entries or flush appropriate forwarding database
+		 * for the given port, if we are moving it from Learning or
+		 * Forwarding state, to Disabled or Blocking or Listening state.
+		 * Ports that were standalone before the STP state change don't
+		 * need to fast age the FDB, since address learning is off in
+		 * standalone mode.
+		 */
+
+		if ((dp->stp_state == BR_STATE_LEARNING ||
+		     dp->stp_state == BR_STATE_FORWARDING) &&
+		    (state == BR_STATE_DISABLED ||
+		     state == BR_STATE_BLOCKING ||
+		     state == BR_STATE_LISTENING))
+			dsa_port_fast_age(dp);
+	}
+
+	dp->stp_state = state;
+
+	return 0;
+}
+
+static void dsa_port_set_state_now(struct dsa_port *dp, u8 state,
+				   bool do_fast_age)
+{
+	struct dsa_switch *ds = dp->ds;
+	int err;
+
+	err = dsa_port_set_state(dp, state, do_fast_age);
+	if (err && err != -EOPNOTSUPP) {
+		dev_err(ds->dev, "port %d failed to set STP state %u: %pe\n",
+			dp->index, state, ERR_PTR(err));
+	}
+}
+
+int dsa_port_set_mst_state(struct dsa_port *dp,
+			   const struct switchdev_mst_state *state,
+			   struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dp->ds;
+	u8 prev_state;
+	int err;
+
+	if (!ds->ops->port_mst_state_set)
+		return -EOPNOTSUPP;
+
+	err = br_mst_get_state(dsa_port_to_bridge_port(dp), state->msti,
+			       &prev_state);
+	if (err)
+		return err;
+
+	err = ds->ops->port_mst_state_set(ds, dp->index, state);
+	if (err)
+		return err;
+
+	if (!(dp->learning &&
+	      (prev_state == BR_STATE_LEARNING ||
+	       prev_state == BR_STATE_FORWARDING) &&
+	      (state->state == BR_STATE_DISABLED ||
+	       state->state == BR_STATE_BLOCKING ||
+	       state->state == BR_STATE_LISTENING)))
+		return 0;
+
+	err = dsa_port_msti_fast_age(dp, state->msti);
+	if (err)
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Unable to flush associated VLANs");
+
+	return 0;
+}
+
+int dsa_port_enable_rt(struct dsa_port *dp, struct phy_device *phy)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+	int err;
+
+	if (ds->ops->port_enable) {
+		err = ds->ops->port_enable(ds, port, phy);
+		if (err)
+			return err;
+	}
+
+	if (!dp->bridge)
+		dsa_port_set_state_now(dp, BR_STATE_FORWARDING, false);
+
+	if (dp->pl)
+		phylink_start(dp->pl);
+
+	return 0;
+}
+
+int dsa_port_enable(struct dsa_port *dp, struct phy_device *phy)
+{
+	int err;
+
+	rtnl_lock();
+	err = dsa_port_enable_rt(dp, phy);
+	rtnl_unlock();
+
+	return err;
+}
+
+void dsa_port_disable_rt(struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+
+	if (dp->pl)
+		phylink_stop(dp->pl);
+
+	if (!dp->bridge)
+		dsa_port_set_state_now(dp, BR_STATE_DISABLED, false);
+
+	if (ds->ops->port_disable)
+		ds->ops->port_disable(ds, port);
+}
+
+void dsa_port_disable(struct dsa_port *dp)
+{
+	rtnl_lock();
+	dsa_port_disable_rt(dp);
+	rtnl_unlock();
+}
+
+static void dsa_port_reset_vlan_filtering(struct dsa_port *dp,
+					  struct dsa_bridge bridge)
+{
+	struct netlink_ext_ack extack = {0};
+	bool change_vlan_filtering = false;
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_port *other_dp;
+	bool vlan_filtering;
+	int err;
+
+	if (ds->needs_standalone_vlan_filtering &&
+	    !br_vlan_enabled(bridge.dev)) {
+		change_vlan_filtering = true;
+		vlan_filtering = true;
+	} else if (!ds->needs_standalone_vlan_filtering &&
+		   br_vlan_enabled(bridge.dev)) {
+		change_vlan_filtering = true;
+		vlan_filtering = false;
+	}
+
+	/* If the bridge was vlan_filtering, the bridge core doesn't trigger an
+	 * event for changing vlan_filtering setting upon slave ports leaving
+	 * it. That is a good thing, because that lets us handle it and also
+	 * handle the case where the switch's vlan_filtering setting is global
+	 * (not per port). When that happens, the correct moment to trigger the
+	 * vlan_filtering callback is only when the last port leaves the last
+	 * VLAN-aware bridge.
+	 */
+	if (change_vlan_filtering && ds->vlan_filtering_is_global) {
+		dsa_switch_for_each_port(other_dp, ds) {
+			struct net_device *br = dsa_port_bridge_dev_get(other_dp);
+
+			if (br && br_vlan_enabled(br)) {
+				change_vlan_filtering = false;
+				break;
+			}
+		}
+	}
+
+	if (!change_vlan_filtering)
+		return;
+
+	err = dsa_port_vlan_filtering(dp, vlan_filtering, &extack);
+	if (extack._msg) {
+		dev_err(ds->dev, "port %d: %s\n", dp->index,
+			extack._msg);
+	}
+	if (err && err != -EOPNOTSUPP) {
+		dev_err(ds->dev,
+			"port %d failed to reset VLAN filtering to %d: %pe\n",
+		       dp->index, vlan_filtering, ERR_PTR(err));
+	}
+}
+
+static int dsa_port_inherit_brport_flags(struct dsa_port *dp,
+					 struct netlink_ext_ack *extack)
+{
+	const unsigned long mask = BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD |
+				   BR_BCAST_FLOOD | BR_PORT_LOCKED;
+	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
+	int flag, err;
+
+	for_each_set_bit(flag, &mask, 32) {
+		struct switchdev_brport_flags flags = {0};
+
+		flags.mask = BIT(flag);
+
+		if (br_port_flag_is_set(brport_dev, BIT(flag)))
+			flags.val = BIT(flag);
+
+		err = dsa_port_bridge_flags(dp, flags, extack);
+		if (err && err != -EOPNOTSUPP)
+			return err;
+	}
+
+	return 0;
+}
+
+static void dsa_port_clear_brport_flags(struct dsa_port *dp)
+{
+	const unsigned long val = BR_FLOOD | BR_MCAST_FLOOD | BR_BCAST_FLOOD;
+	const unsigned long mask = BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD |
+				   BR_BCAST_FLOOD | BR_PORT_LOCKED;
+	int flag, err;
+
+	for_each_set_bit(flag, &mask, 32) {
+		struct switchdev_brport_flags flags = {0};
+
+		flags.mask = BIT(flag);
+		flags.val = val & BIT(flag);
+
+		err = dsa_port_bridge_flags(dp, flags, NULL);
+		if (err && err != -EOPNOTSUPP)
+			dev_err(dp->ds->dev,
+				"failed to clear bridge port flag %lu: %pe\n",
+				flags.val, ERR_PTR(err));
+	}
+}
+
+static int dsa_port_switchdev_sync_attrs(struct dsa_port *dp,
+					 struct netlink_ext_ack *extack)
+{
+	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
+	struct net_device *br = dsa_port_bridge_dev_get(dp);
+	int err;
+
+	err = dsa_port_inherit_brport_flags(dp, extack);
+	if (err)
+		return err;
+
+	err = dsa_port_set_state(dp, br_port_get_stp_state(brport_dev), false);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = dsa_port_vlan_filtering(dp, br_vlan_enabled(br), extack);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = dsa_port_ageing_time(dp, br_get_ageing_time(br));
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	return 0;
+}
+
+static void dsa_port_switchdev_unsync_attrs(struct dsa_port *dp,
+					    struct dsa_bridge bridge)
+{
+	/* Configure the port for standalone mode (no address learning,
+	 * flood everything).
+	 * The bridge only emits SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS events
+	 * when the user requests it through netlink or sysfs, but not
+	 * automatically at port join or leave, so we need to handle resetting
+	 * the brport flags ourselves. But we even prefer it that way, because
+	 * otherwise, some setups might never get the notification they need,
+	 * for example, when a port leaves a LAG that offloads the bridge,
+	 * it becomes standalone, but as far as the bridge is concerned, no
+	 * port ever left.
+	 */
+	dsa_port_clear_brport_flags(dp);
+
+	/* Port left the bridge, put in BR_STATE_DISABLED by the bridge layer,
+	 * so allow it to be in BR_STATE_FORWARDING to be kept functional
+	 */
+	dsa_port_set_state_now(dp, BR_STATE_FORWARDING, true);
+
+	dsa_port_reset_vlan_filtering(dp, bridge);
+
+	/* Ageing time may be global to the switch chip, so don't change it
+	 * here because we have no good reason (or value) to change it to.
+	 */
+}
+
+static int dsa_port_bridge_create(struct dsa_port *dp,
+				  struct net_device *br,
+				  struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_bridge *bridge;
+
+	bridge = dsa_tree_bridge_find(ds->dst, br);
+	if (bridge) {
+		refcount_inc(&bridge->refcount);
+		dp->bridge = bridge;
+		return 0;
+	}
+
+	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
+	if (!bridge)
+		return -ENOMEM;
+
+	refcount_set(&bridge->refcount, 1);
+
+	bridge->dev = br;
+
+	bridge->num = dsa_bridge_num_get(br, ds->max_num_bridges);
+	if (ds->max_num_bridges && !bridge->num) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Range of offloadable bridges exceeded");
+		kfree(bridge);
+		return -EOPNOTSUPP;
+	}
+
+	dp->bridge = bridge;
+
+	return 0;
+}
+
+static void dsa_port_bridge_destroy(struct dsa_port *dp,
+				    const struct net_device *br)
+{
+	struct dsa_bridge *bridge = dp->bridge;
+
+	dp->bridge = NULL;
+
+	if (!refcount_dec_and_test(&bridge->refcount))
+		return;
+
+	if (bridge->num)
+		dsa_bridge_num_put(br, bridge->num);
+
+	kfree(bridge);
+}
+
+static bool dsa_port_supports_mst(struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	return ds->ops->vlan_msti_set &&
+		ds->ops->port_mst_state_set &&
+		ds->ops->port_vlan_fast_age &&
+		dsa_port_can_configure_learning(dp);
+}
+
+int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br,
+			 struct netlink_ext_ack *extack)
+{
+	struct dsa_notifier_bridge_info info = {
+		.dp = dp,
+		.extack = extack,
+	};
+	struct net_device *dev = dp->slave;
+	struct net_device *brport_dev;
+	int err;
+
+	if (br_mst_enabled(br) && !dsa_port_supports_mst(dp))
+		return -EOPNOTSUPP;
+
+	/* Here the interface is already bridged. Reflect the current
+	 * configuration so that drivers can program their chips accordingly.
+	 */
+	err = dsa_port_bridge_create(dp, br, extack);
+	if (err)
+		return err;
+
+	brport_dev = dsa_port_to_bridge_port(dp);
+
+	info.bridge = *dp->bridge;
+	err = dsa_broadcast(DSA_NOTIFIER_BRIDGE_JOIN, &info);
+	if (err)
+		goto out_rollback;
+
+	/* Drivers which support bridge TX forwarding should set this */
+	dp->bridge->tx_fwd_offload = info.tx_fwd_offload;
+
+	err = switchdev_bridge_port_offload(brport_dev, dev, dp,
+					    &dsa_slave_switchdev_notifier,
+					    &dsa_slave_switchdev_blocking_notifier,
+					    dp->bridge->tx_fwd_offload, extack);
+	if (err)
+		goto out_rollback_unbridge;
+
+	err = dsa_port_switchdev_sync_attrs(dp, extack);
+	if (err)
+		goto out_rollback_unoffload;
+
+	return 0;
+
+out_rollback_unoffload:
+	switchdev_bridge_port_unoffload(brport_dev, dp,
+					&dsa_slave_switchdev_notifier,
+					&dsa_slave_switchdev_blocking_notifier);
+	dsa_flush_workqueue();
+out_rollback_unbridge:
+	dsa_broadcast(DSA_NOTIFIER_BRIDGE_LEAVE, &info);
+out_rollback:
+	dsa_port_bridge_destroy(dp, br);
+	return err;
+}
+
+void dsa_port_pre_bridge_leave(struct dsa_port *dp, struct net_device *br)
+{
+	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
+
+	/* Don't try to unoffload something that is not offloaded */
+	if (!brport_dev)
+		return;
+
+	switchdev_bridge_port_unoffload(brport_dev, dp,
+					&dsa_slave_switchdev_notifier,
+					&dsa_slave_switchdev_blocking_notifier);
+
+	dsa_flush_workqueue();
+}
+
+void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br)
+{
+	struct dsa_notifier_bridge_info info = {
+		.dp = dp,
+	};
+	int err;
+
+	/* If the port could not be offloaded to begin with, then
+	 * there is nothing to do.
+	 */
+	if (!dp->bridge)
+		return;
+
+	info.bridge = *dp->bridge;
+
+	/* Here the port is already unbridged. Reflect the current configuration
+	 * so that drivers can program their chips accordingly.
+	 */
+	dsa_port_bridge_destroy(dp, br);
+
+	err = dsa_broadcast(DSA_NOTIFIER_BRIDGE_LEAVE, &info);
+	if (err)
+		dev_err(dp->ds->dev,
+			"port %d failed to notify DSA_NOTIFIER_BRIDGE_LEAVE: %pe\n",
+			dp->index, ERR_PTR(err));
+
+	dsa_port_switchdev_unsync_attrs(dp, info.bridge);
+}
+
+int dsa_port_lag_change(struct dsa_port *dp,
+			struct netdev_lag_lower_state_info *linfo)
+{
+	struct dsa_notifier_lag_info info = {
+		.dp = dp,
+	};
+	bool tx_enabled;
+
+	if (!dp->lag)
+		return 0;
+
+	/* On statically configured aggregates (e.g. loadbalance
+	 * without LACP) ports will always be tx_enabled, even if the
+	 * link is down. Thus we require both link_up and tx_enabled
+	 * in order to include it in the tx set.
+	 */
+	tx_enabled = linfo->link_up && linfo->tx_enabled;
+
+	if (tx_enabled == dp->lag_tx_enabled)
+		return 0;
+
+	dp->lag_tx_enabled = tx_enabled;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_LAG_CHANGE, &info);
+}
+
+static int dsa_port_lag_create(struct dsa_port *dp,
+			       struct net_device *lag_dev)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_lag *lag;
+
+	lag = dsa_tree_lag_find(ds->dst, lag_dev);
+	if (lag) {
+		refcount_inc(&lag->refcount);
+		dp->lag = lag;
+		return 0;
+	}
+
+	lag = kzalloc(sizeof(*lag), GFP_KERNEL);
+	if (!lag)
+		return -ENOMEM;
+
+	refcount_set(&lag->refcount, 1);
+	mutex_init(&lag->fdb_lock);
+	INIT_LIST_HEAD(&lag->fdbs);
+	lag->dev = lag_dev;
+	dsa_lag_map(ds->dst, lag);
+	dp->lag = lag;
+
+	return 0;
+}
+
+static void dsa_port_lag_destroy(struct dsa_port *dp)
+{
+	struct dsa_lag *lag = dp->lag;
+
+	dp->lag = NULL;
+	dp->lag_tx_enabled = false;
+
+	if (!refcount_dec_and_test(&lag->refcount))
+		return;
+
+	WARN_ON(!list_empty(&lag->fdbs));
+	dsa_lag_unmap(dp->ds->dst, lag);
+	kfree(lag);
+}
+
+int dsa_port_lag_join(struct dsa_port *dp, struct net_device *lag_dev,
+		      struct netdev_lag_upper_info *uinfo,
+		      struct netlink_ext_ack *extack)
+{
+	struct dsa_notifier_lag_info info = {
+		.dp = dp,
+		.info = uinfo,
+		.extack = extack,
+	};
+	struct net_device *bridge_dev;
+	int err;
+
+	err = dsa_port_lag_create(dp, lag_dev);
+	if (err)
+		goto err_lag_create;
+
+	info.lag = *dp->lag;
+	err = dsa_port_notify(dp, DSA_NOTIFIER_LAG_JOIN, &info);
+	if (err)
+		goto err_lag_join;
+
+	bridge_dev = netdev_master_upper_dev_get(lag_dev);
+	if (!bridge_dev || !netif_is_bridge_master(bridge_dev))
+		return 0;
+
+	err = dsa_port_bridge_join(dp, bridge_dev, extack);
+	if (err)
+		goto err_bridge_join;
+
+	return 0;
+
+err_bridge_join:
+	dsa_port_notify(dp, DSA_NOTIFIER_LAG_LEAVE, &info);
+err_lag_join:
+	dsa_port_lag_destroy(dp);
+err_lag_create:
+	return err;
+}
+
+void dsa_port_pre_lag_leave(struct dsa_port *dp, struct net_device *lag_dev)
+{
+	struct net_device *br = dsa_port_bridge_dev_get(dp);
+
+	if (br)
+		dsa_port_pre_bridge_leave(dp, br);
+}
+
+void dsa_port_lag_leave(struct dsa_port *dp, struct net_device *lag_dev)
+{
+	struct net_device *br = dsa_port_bridge_dev_get(dp);
+	struct dsa_notifier_lag_info info = {
+		.dp = dp,
+	};
+	int err;
+
+	if (!dp->lag)
+		return;
+
+	/* Port might have been part of a LAG that in turn was
+	 * attached to a bridge.
+	 */
+	if (br)
+		dsa_port_bridge_leave(dp, br);
+
+	info.lag = *dp->lag;
+
+	dsa_port_lag_destroy(dp);
+
+	err = dsa_port_notify(dp, DSA_NOTIFIER_LAG_LEAVE, &info);
+	if (err)
+		dev_err(dp->ds->dev,
+			"port %d failed to notify DSA_NOTIFIER_LAG_LEAVE: %pe\n",
+			dp->index, ERR_PTR(err));
+}
+
+/* Must be called under rcu_read_lock() */
+static bool dsa_port_can_apply_vlan_filtering(struct dsa_port *dp,
+					      bool vlan_filtering,
+					      struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_port *other_dp;
+	int err;
+
+	/* VLAN awareness was off, so the question is "can we turn it on".
+	 * We may have had 8021q uppers, those need to go. Make sure we don't
+	 * enter an inconsistent state: deny changing the VLAN awareness state
+	 * as long as we have 8021q uppers.
+	 */
+	if (vlan_filtering && dsa_port_is_user(dp)) {
+		struct net_device *br = dsa_port_bridge_dev_get(dp);
+		struct net_device *upper_dev, *slave = dp->slave;
+		struct list_head *iter;
+
+		netdev_for_each_upper_dev_rcu(slave, upper_dev, iter) {
+			struct bridge_vlan_info br_info;
+			u16 vid;
+
+			if (!is_vlan_dev(upper_dev))
+				continue;
+
+			vid = vlan_dev_vlan_id(upper_dev);
+
+			/* br_vlan_get_info() returns -EINVAL or -ENOENT if the
+			 * device, respectively the VID is not found, returning
+			 * 0 means success, which is a failure for us here.
+			 */
+			err = br_vlan_get_info(br, vid, &br_info);
+			if (err == 0) {
+				NL_SET_ERR_MSG_MOD(extack,
+						   "Must first remove VLAN uppers having VIDs also present in bridge");
+				return false;
+			}
+		}
+	}
+
+	if (!ds->vlan_filtering_is_global)
+		return true;
+
+	/* For cases where enabling/disabling VLAN awareness is global to the
+	 * switch, we need to handle the case where multiple bridges span
+	 * different ports of the same switch device and one of them has a
+	 * different setting than what is being requested.
+	 */
+	dsa_switch_for_each_port(other_dp, ds) {
+		struct net_device *other_br = dsa_port_bridge_dev_get(other_dp);
+
+		/* If it's the same bridge, it also has same
+		 * vlan_filtering setting => no need to check
+		 */
+		if (!other_br || other_br == dsa_port_bridge_dev_get(dp))
+			continue;
+
+		if (br_vlan_enabled(other_br) != vlan_filtering) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "VLAN filtering is a global setting");
+			return false;
+		}
+	}
+	return true;
+}
+
+int dsa_port_vlan_filtering(struct dsa_port *dp, bool vlan_filtering,
+			    struct netlink_ext_ack *extack)
+{
+	bool old_vlan_filtering = dsa_port_is_vlan_filtering(dp);
+	struct dsa_switch *ds = dp->ds;
+	bool apply;
+	int err;
+
+	if (!ds->ops->port_vlan_filtering)
+		return -EOPNOTSUPP;
+
+	/* We are called from dsa_slave_switchdev_blocking_event(),
+	 * which is not under rcu_read_lock(), unlike
+	 * dsa_slave_switchdev_event().
+	 */
+	rcu_read_lock();
+	apply = dsa_port_can_apply_vlan_filtering(dp, vlan_filtering, extack);
+	rcu_read_unlock();
+	if (!apply)
+		return -EINVAL;
+
+	if (dsa_port_is_vlan_filtering(dp) == vlan_filtering)
+		return 0;
+
+	err = ds->ops->port_vlan_filtering(ds, dp->index, vlan_filtering,
+					   extack);
+	if (err)
+		return err;
+
+	if (ds->vlan_filtering_is_global) {
+		struct dsa_port *other_dp;
+
+		ds->vlan_filtering = vlan_filtering;
+
+		dsa_switch_for_each_user_port(other_dp, ds) {
+			struct net_device *slave = other_dp->slave;
+
+			/* We might be called in the unbind path, so not
+			 * all slave devices might still be registered.
+			 */
+			if (!slave)
+				continue;
+
+			err = dsa_slave_manage_vlan_filtering(slave,
+							      vlan_filtering);
+			if (err)
+				goto restore;
+		}
+	} else {
+		dp->vlan_filtering = vlan_filtering;
+
+		err = dsa_slave_manage_vlan_filtering(dp->slave,
+						      vlan_filtering);
+		if (err)
+			goto restore;
+	}
+
+	return 0;
+
+restore:
+	ds->ops->port_vlan_filtering(ds, dp->index, old_vlan_filtering, NULL);
+
+	if (ds->vlan_filtering_is_global)
+		ds->vlan_filtering = old_vlan_filtering;
+	else
+		dp->vlan_filtering = old_vlan_filtering;
+
+	return err;
+}
+
+/* This enforces legacy behavior for switch drivers which assume they can't
+ * receive VLAN configuration when enslaved to a bridge with vlan_filtering=0
+ */
+bool dsa_port_skip_vlan_configuration(struct dsa_port *dp)
+{
+	struct net_device *br = dsa_port_bridge_dev_get(dp);
+	struct dsa_switch *ds = dp->ds;
+
+	if (!br)
+		return false;
+
+	return !ds->configure_vlan_while_not_filtering && !br_vlan_enabled(br);
+}
+
+int dsa_port_ageing_time(struct dsa_port *dp, clock_t ageing_clock)
+{
+	unsigned long ageing_jiffies = clock_t_to_jiffies(ageing_clock);
+	unsigned int ageing_time = jiffies_to_msecs(ageing_jiffies);
+	struct dsa_notifier_ageing_time_info info;
+	int err;
+
+	info.ageing_time = ageing_time;
+
+	err = dsa_port_notify(dp, DSA_NOTIFIER_AGEING_TIME, &info);
+	if (err)
+		return err;
+
+	dp->ageing_time = ageing_time;
+
+	return 0;
+}
+
+int dsa_port_mst_enable(struct dsa_port *dp, bool on,
+			struct netlink_ext_ack *extack)
+{
+	if (on && !dsa_port_supports_mst(dp)) {
+		NL_SET_ERR_MSG_MOD(extack, "Hardware does not support MST");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+int dsa_port_pre_bridge_flags(const struct dsa_port *dp,
+			      struct switchdev_brport_flags flags,
+			      struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->port_pre_bridge_flags)
+		return -EINVAL;
+
+	return ds->ops->port_pre_bridge_flags(ds, dp->index, flags, extack);
+}
+
+int dsa_port_bridge_flags(struct dsa_port *dp,
+			  struct switchdev_brport_flags flags,
+			  struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dp->ds;
+	int err;
+
+	if (!ds->ops->port_bridge_flags)
+		return -EOPNOTSUPP;
+
+	err = ds->ops->port_bridge_flags(ds, dp->index, flags, extack);
+	if (err)
+		return err;
+
+	if (flags.mask & BR_LEARNING) {
+		bool learning = flags.val & BR_LEARNING;
+
+		if (learning == dp->learning)
+			return 0;
+
+		if ((dp->learning && !learning) &&
+		    (dp->stp_state == BR_STATE_LEARNING ||
+		     dp->stp_state == BR_STATE_FORWARDING))
+			dsa_port_fast_age(dp);
+
+		dp->learning = learning;
+	}
+
+	return 0;
+}
+
+void dsa_port_set_host_flood(struct dsa_port *dp, bool uc, bool mc)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->port_set_host_flood)
+		ds->ops->port_set_host_flood(ds, dp->index, uc, mc);
+}
+
+int dsa_port_vlan_msti(struct dsa_port *dp,
+		       const struct switchdev_vlan_msti *msti)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->vlan_msti_set)
+		return -EOPNOTSUPP;
+
+	return ds->ops->vlan_msti_set(ds, *dp->bridge, msti);
+}
+
+int dsa_port_mtu_change(struct dsa_port *dp, int new_mtu)
+{
+	struct dsa_notifier_mtu_info info = {
+		.dp = dp,
+		.mtu = new_mtu,
+	};
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_MTU, &info);
+}
+
+int dsa_port_fdb_add(struct dsa_port *dp, const unsigned char *addr,
+		     u16 vid)
+{
+	struct dsa_notifier_fdb_info info = {
+		.dp = dp,
+		.addr = addr,
+		.vid = vid,
+		.db = {
+			.type = DSA_DB_BRIDGE,
+			.bridge = *dp->bridge,
+		},
+	};
+
+	/* Refcounting takes bridge.num as a key, and should be global for all
+	 * bridges in the absence of FDB isolation, and per bridge otherwise.
+	 * Force the bridge.num to zero here in the absence of FDB isolation.
+	 */
+	if (!dp->ds->fdb_isolation)
+		info.db.bridge.num = 0;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_FDB_ADD, &info);
+}
+
+int dsa_port_fdb_del(struct dsa_port *dp, const unsigned char *addr,
+		     u16 vid)
+{
+	struct dsa_notifier_fdb_info info = {
+		.dp = dp,
+		.addr = addr,
+		.vid = vid,
+		.db = {
+			.type = DSA_DB_BRIDGE,
+			.bridge = *dp->bridge,
+		},
+	};
+
+	if (!dp->ds->fdb_isolation)
+		info.db.bridge.num = 0;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_FDB_DEL, &info);
+}
+
+static int dsa_port_host_fdb_add(struct dsa_port *dp,
+				 const unsigned char *addr, u16 vid,
+				 struct dsa_db db)
+{
+	struct dsa_notifier_fdb_info info = {
+		.dp = dp,
+		.addr = addr,
+		.vid = vid,
+		.db = db,
+	};
+
+	if (!dp->ds->fdb_isolation)
+		info.db.bridge.num = 0;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_HOST_FDB_ADD, &info);
+}
+
+int dsa_port_standalone_host_fdb_add(struct dsa_port *dp,
+				     const unsigned char *addr, u16 vid)
+{
+	struct dsa_db db = {
+		.type = DSA_DB_PORT,
+		.dp = dp,
+	};
+
+	return dsa_port_host_fdb_add(dp, addr, vid, db);
+}
+
+int dsa_port_bridge_host_fdb_add(struct dsa_port *dp,
+				 const unsigned char *addr, u16 vid)
+{
+	struct net_device *master = dsa_port_to_master(dp);
+	struct dsa_db db = {
+		.type = DSA_DB_BRIDGE,
+		.bridge = *dp->bridge,
+	};
+	int err;
+
+	/* Avoid a call to __dev_set_promiscuity() on the master, which
+	 * requires rtnl_lock(), since we can't guarantee that is held here,
+	 * and we can't take it either.
+	 */
+	if (master->priv_flags & IFF_UNICAST_FLT) {
+		err = dev_uc_add(master, addr);
+		if (err)
+			return err;
+	}
+
+	return dsa_port_host_fdb_add(dp, addr, vid, db);
+}
+
+static int dsa_port_host_fdb_del(struct dsa_port *dp,
+				 const unsigned char *addr, u16 vid,
+				 struct dsa_db db)
+{
+	struct dsa_notifier_fdb_info info = {
+		.dp = dp,
+		.addr = addr,
+		.vid = vid,
+		.db = db,
+	};
+
+	if (!dp->ds->fdb_isolation)
+		info.db.bridge.num = 0;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_HOST_FDB_DEL, &info);
+}
+
+int dsa_port_standalone_host_fdb_del(struct dsa_port *dp,
+				     const unsigned char *addr, u16 vid)
+{
+	struct dsa_db db = {
+		.type = DSA_DB_PORT,
+		.dp = dp,
+	};
+
+	return dsa_port_host_fdb_del(dp, addr, vid, db);
+}
+
+int dsa_port_bridge_host_fdb_del(struct dsa_port *dp,
+				 const unsigned char *addr, u16 vid)
+{
+	struct net_device *master = dsa_port_to_master(dp);
+	struct dsa_db db = {
+		.type = DSA_DB_BRIDGE,
+		.bridge = *dp->bridge,
+	};
+	int err;
+
+	if (master->priv_flags & IFF_UNICAST_FLT) {
+		err = dev_uc_del(master, addr);
+		if (err)
+			return err;
+	}
+
+	return dsa_port_host_fdb_del(dp, addr, vid, db);
+}
+
+int dsa_port_lag_fdb_add(struct dsa_port *dp, const unsigned char *addr,
+			 u16 vid)
+{
+	struct dsa_notifier_lag_fdb_info info = {
+		.lag = dp->lag,
+		.addr = addr,
+		.vid = vid,
+		.db = {
+			.type = DSA_DB_BRIDGE,
+			.bridge = *dp->bridge,
+		},
+	};
+
+	if (!dp->ds->fdb_isolation)
+		info.db.bridge.num = 0;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_LAG_FDB_ADD, &info);
+}
+
+int dsa_port_lag_fdb_del(struct dsa_port *dp, const unsigned char *addr,
+			 u16 vid)
+{
+	struct dsa_notifier_lag_fdb_info info = {
+		.lag = dp->lag,
+		.addr = addr,
+		.vid = vid,
+		.db = {
+			.type = DSA_DB_BRIDGE,
+			.bridge = *dp->bridge,
+		},
+	};
+
+	if (!dp->ds->fdb_isolation)
+		info.db.bridge.num = 0;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_LAG_FDB_DEL, &info);
+}
+
+int dsa_port_fdb_dump(struct dsa_port *dp, dsa_fdb_dump_cb_t *cb, void *data)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+
+	if (!ds->ops->port_fdb_dump)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_fdb_dump(ds, port, cb, data);
+}
+
+int dsa_port_mdb_add(const struct dsa_port *dp,
+		     const struct switchdev_obj_port_mdb *mdb)
+{
+	struct dsa_notifier_mdb_info info = {
+		.dp = dp,
+		.mdb = mdb,
+		.db = {
+			.type = DSA_DB_BRIDGE,
+			.bridge = *dp->bridge,
+		},
+	};
+
+	if (!dp->ds->fdb_isolation)
+		info.db.bridge.num = 0;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_MDB_ADD, &info);
+}
+
+int dsa_port_mdb_del(const struct dsa_port *dp,
+		     const struct switchdev_obj_port_mdb *mdb)
+{
+	struct dsa_notifier_mdb_info info = {
+		.dp = dp,
+		.mdb = mdb,
+		.db = {
+			.type = DSA_DB_BRIDGE,
+			.bridge = *dp->bridge,
+		},
+	};
+
+	if (!dp->ds->fdb_isolation)
+		info.db.bridge.num = 0;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_MDB_DEL, &info);
+}
+
+static int dsa_port_host_mdb_add(const struct dsa_port *dp,
+				 const struct switchdev_obj_port_mdb *mdb,
+				 struct dsa_db db)
+{
+	struct dsa_notifier_mdb_info info = {
+		.dp = dp,
+		.mdb = mdb,
+		.db = db,
+	};
+
+	if (!dp->ds->fdb_isolation)
+		info.db.bridge.num = 0;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_HOST_MDB_ADD, &info);
+}
+
+int dsa_port_standalone_host_mdb_add(const struct dsa_port *dp,
+				     const struct switchdev_obj_port_mdb *mdb)
+{
+	struct dsa_db db = {
+		.type = DSA_DB_PORT,
+		.dp = dp,
+	};
+
+	return dsa_port_host_mdb_add(dp, mdb, db);
+}
+
+int dsa_port_bridge_host_mdb_add(const struct dsa_port *dp,
+				 const struct switchdev_obj_port_mdb *mdb)
+{
+	struct net_device *master = dsa_port_to_master(dp);
+	struct dsa_db db = {
+		.type = DSA_DB_BRIDGE,
+		.bridge = *dp->bridge,
+	};
+	int err;
+
+	err = dev_mc_add(master, mdb->addr);
+	if (err)
+		return err;
+
+	return dsa_port_host_mdb_add(dp, mdb, db);
+}
+
+static int dsa_port_host_mdb_del(const struct dsa_port *dp,
+				 const struct switchdev_obj_port_mdb *mdb,
+				 struct dsa_db db)
+{
+	struct dsa_notifier_mdb_info info = {
+		.dp = dp,
+		.mdb = mdb,
+		.db = db,
+	};
+
+	if (!dp->ds->fdb_isolation)
+		info.db.bridge.num = 0;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_HOST_MDB_DEL, &info);
+}
+
+int dsa_port_standalone_host_mdb_del(const struct dsa_port *dp,
+				     const struct switchdev_obj_port_mdb *mdb)
+{
+	struct dsa_db db = {
+		.type = DSA_DB_PORT,
+		.dp = dp,
+	};
+
+	return dsa_port_host_mdb_del(dp, mdb, db);
+}
+
+int dsa_port_bridge_host_mdb_del(const struct dsa_port *dp,
+				 const struct switchdev_obj_port_mdb *mdb)
+{
+	struct net_device *master = dsa_port_to_master(dp);
+	struct dsa_db db = {
+		.type = DSA_DB_BRIDGE,
+		.bridge = *dp->bridge,
+	};
+	int err;
+
+	err = dev_mc_del(master, mdb->addr);
+	if (err)
+		return err;
+
+	return dsa_port_host_mdb_del(dp, mdb, db);
+}
+
+int dsa_port_vlan_add(struct dsa_port *dp,
+		      const struct switchdev_obj_port_vlan *vlan,
+		      struct netlink_ext_ack *extack)
+{
+	struct dsa_notifier_vlan_info info = {
+		.dp = dp,
+		.vlan = vlan,
+		.extack = extack,
+	};
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_VLAN_ADD, &info);
+}
+
+int dsa_port_vlan_del(struct dsa_port *dp,
+		      const struct switchdev_obj_port_vlan *vlan)
+{
+	struct dsa_notifier_vlan_info info = {
+		.dp = dp,
+		.vlan = vlan,
+	};
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_VLAN_DEL, &info);
+}
+
+int dsa_port_host_vlan_add(struct dsa_port *dp,
+			   const struct switchdev_obj_port_vlan *vlan,
+			   struct netlink_ext_ack *extack)
+{
+	struct net_device *master = dsa_port_to_master(dp);
+	struct dsa_notifier_vlan_info info = {
+		.dp = dp,
+		.vlan = vlan,
+		.extack = extack,
+	};
+	int err;
+
+	err = dsa_port_notify(dp, DSA_NOTIFIER_HOST_VLAN_ADD, &info);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	vlan_vid_add(master, htons(ETH_P_8021Q), vlan->vid);
+
+	return err;
+}
+
+int dsa_port_host_vlan_del(struct dsa_port *dp,
+			   const struct switchdev_obj_port_vlan *vlan)
+{
+	struct net_device *master = dsa_port_to_master(dp);
+	struct dsa_notifier_vlan_info info = {
+		.dp = dp,
+		.vlan = vlan,
+	};
+	int err;
+
+	err = dsa_port_notify(dp, DSA_NOTIFIER_HOST_VLAN_DEL, &info);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	vlan_vid_del(master, htons(ETH_P_8021Q), vlan->vid);
+
+	return err;
+}
+
+int dsa_port_mrp_add(const struct dsa_port *dp,
+		     const struct switchdev_obj_mrp *mrp)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->port_mrp_add)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_mrp_add(ds, dp->index, mrp);
+}
+
+int dsa_port_mrp_del(const struct dsa_port *dp,
+		     const struct switchdev_obj_mrp *mrp)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->port_mrp_del)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_mrp_del(ds, dp->index, mrp);
+}
+
+int dsa_port_mrp_add_ring_role(const struct dsa_port *dp,
+			       const struct switchdev_obj_ring_role_mrp *mrp)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->port_mrp_add_ring_role)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_mrp_add_ring_role(ds, dp->index, mrp);
+}
+
+int dsa_port_mrp_del_ring_role(const struct dsa_port *dp,
+			       const struct switchdev_obj_ring_role_mrp *mrp)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->port_mrp_del_ring_role)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_mrp_del_ring_role(ds, dp->index, mrp);
+}
+
+static int dsa_port_assign_master(struct dsa_port *dp,
+				  struct net_device *master,
+				  struct netlink_ext_ack *extack,
+				  bool fail_on_err)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index, err;
+
+	err = ds->ops->port_change_master(ds, port, master, extack);
+	if (err && !fail_on_err)
+		dev_err(ds->dev, "port %d failed to assign master %s: %pe\n",
+			port, master->name, ERR_PTR(err));
+
+	if (err && fail_on_err)
+		return err;
+
+	dp->cpu_dp = master->dsa_ptr;
+	dp->cpu_port_in_lag = netif_is_lag_master(master);
+
+	return 0;
+}
+
+/* Change the dp->cpu_dp affinity for a user port. Note that both cross-chip
+ * notifiers and drivers have implicit assumptions about user-to-CPU-port
+ * mappings, so we unfortunately cannot delay the deletion of the objects
+ * (switchdev, standalone addresses, standalone VLANs) on the old CPU port
+ * until the new CPU port has been set up. So we need to completely tear down
+ * the old CPU port before changing it, and restore it on errors during the
+ * bringup of the new one.
+ */
+int dsa_port_change_master(struct dsa_port *dp, struct net_device *master,
+			   struct netlink_ext_ack *extack)
+{
+	struct net_device *bridge_dev = dsa_port_bridge_dev_get(dp);
+	struct net_device *old_master = dsa_port_to_master(dp);
+	struct net_device *dev = dp->slave;
+	struct dsa_switch *ds = dp->ds;
+	bool vlan_filtering;
+	int err, tmp;
+
+	/* Bridges may hold host FDB, MDB and VLAN objects. These need to be
+	 * migrated, so dynamically unoffload and later reoffload the bridge
+	 * port.
+	 */
+	if (bridge_dev) {
+		dsa_port_pre_bridge_leave(dp, bridge_dev);
+		dsa_port_bridge_leave(dp, bridge_dev);
+	}
+
+	/* The port might still be VLAN filtering even if it's no longer
+	 * under a bridge, either due to ds->vlan_filtering_is_global or
+	 * ds->needs_standalone_vlan_filtering. In turn this means VLANs
+	 * on the CPU port.
+	 */
+	vlan_filtering = dsa_port_is_vlan_filtering(dp);
+	if (vlan_filtering) {
+		err = dsa_slave_manage_vlan_filtering(dev, false);
+		if (err) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "Failed to remove standalone VLANs");
+			goto rewind_old_bridge;
+		}
+	}
+
+	/* Standalone addresses, and addresses of upper interfaces like
+	 * VLAN, LAG, HSR need to be migrated.
+	 */
+	dsa_slave_unsync_ha(dev);
+
+	err = dsa_port_assign_master(dp, master, extack, true);
+	if (err)
+		goto rewind_old_addrs;
+
+	dsa_slave_sync_ha(dev);
+
+	if (vlan_filtering) {
+		err = dsa_slave_manage_vlan_filtering(dev, true);
+		if (err) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "Failed to restore standalone VLANs");
+			goto rewind_new_addrs;
+		}
+	}
+
+	if (bridge_dev) {
+		err = dsa_port_bridge_join(dp, bridge_dev, extack);
+		if (err && err == -EOPNOTSUPP) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "Failed to reoffload bridge");
+			goto rewind_new_vlan;
+		}
+	}
+
+	return 0;
+
+rewind_new_vlan:
+	if (vlan_filtering)
+		dsa_slave_manage_vlan_filtering(dev, false);
+
+rewind_new_addrs:
+	dsa_slave_unsync_ha(dev);
+
+	dsa_port_assign_master(dp, old_master, NULL, false);
+
+/* Restore the objects on the old CPU port */
+rewind_old_addrs:
+	dsa_slave_sync_ha(dev);
+
+	if (vlan_filtering) {
+		tmp = dsa_slave_manage_vlan_filtering(dev, true);
+		if (tmp) {
+			dev_err(ds->dev,
+				"port %d failed to restore standalone VLANs: %pe\n",
+				dp->index, ERR_PTR(tmp));
+		}
+	}
+
+rewind_old_bridge:
+	if (bridge_dev) {
+		tmp = dsa_port_bridge_join(dp, bridge_dev, extack);
+		if (tmp) {
+			dev_err(ds->dev,
+				"port %d failed to rejoin bridge %s: %pe\n",
+				dp->index, bridge_dev->name, ERR_PTR(tmp));
+		}
+	}
+
+	return err;
+}
+
+void dsa_port_set_tag_protocol(struct dsa_port *cpu_dp,
+			       const struct dsa_device_ops *tag_ops)
+{
+	cpu_dp->rcv = tag_ops->rcv;
+	cpu_dp->tag_ops = tag_ops;
+}
+
+static struct phy_device *dsa_port_get_phy_device(struct dsa_port *dp)
+{
+	struct device_node *phy_dn;
+	struct phy_device *phydev;
+
+	phy_dn = of_parse_phandle(dp->dn, "phy-handle", 0);
+	if (!phy_dn)
+		return NULL;
+
+	phydev = of_phy_find_device(phy_dn);
+	if (!phydev) {
+		of_node_put(phy_dn);
+		return ERR_PTR(-EPROBE_DEFER);
+	}
+
+	of_node_put(phy_dn);
+	return phydev;
+}
+
+static void dsa_port_phylink_validate(struct phylink_config *config,
+				      unsigned long *supported,
+				      struct phylink_link_state *state)
+{
+	struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->phylink_validate) {
+		if (config->mac_capabilities)
+			phylink_generic_validate(config, supported, state);
+		return;
+	}
+
+	ds->ops->phylink_validate(ds, dp->index, supported, state);
+}
+
+static void dsa_port_phylink_mac_pcs_get_state(struct phylink_config *config,
+					       struct phylink_link_state *state)
+{
+	struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
+	struct dsa_switch *ds = dp->ds;
+	int err;
+
+	/* Only called for inband modes */
+	if (!ds->ops->phylink_mac_link_state) {
+		state->link = 0;
+		return;
+	}
+
+	err = ds->ops->phylink_mac_link_state(ds, dp->index, state);
+	if (err < 0) {
+		dev_err(ds->dev, "p%d: phylink_mac_link_state() failed: %d\n",
+			dp->index, err);
+		state->link = 0;
+	}
+}
+
+static struct phylink_pcs *
+dsa_port_phylink_mac_select_pcs(struct phylink_config *config,
+				phy_interface_t interface)
+{
+	struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
+	struct phylink_pcs *pcs = ERR_PTR(-EOPNOTSUPP);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->phylink_mac_select_pcs)
+		pcs = ds->ops->phylink_mac_select_pcs(ds, dp->index, interface);
+
+	return pcs;
+}
+
+static void dsa_port_phylink_mac_config(struct phylink_config *config,
+					unsigned int mode,
+					const struct phylink_link_state *state)
+{
+	struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->phylink_mac_config)
+		return;
+
+	ds->ops->phylink_mac_config(ds, dp->index, mode, state);
+}
+
+static void dsa_port_phylink_mac_an_restart(struct phylink_config *config)
+{
+	struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->phylink_mac_an_restart)
+		return;
+
+	ds->ops->phylink_mac_an_restart(ds, dp->index);
+}
+
+static void dsa_port_phylink_mac_link_down(struct phylink_config *config,
+					   unsigned int mode,
+					   phy_interface_t interface)
+{
+	struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
+	struct phy_device *phydev = NULL;
+	struct dsa_switch *ds = dp->ds;
+
+	if (dsa_port_is_user(dp))
+		phydev = dp->slave->phydev;
+
+	if (!ds->ops->phylink_mac_link_down) {
+		if (ds->ops->adjust_link && phydev)
+			ds->ops->adjust_link(ds, dp->index, phydev);
+		return;
+	}
+
+	ds->ops->phylink_mac_link_down(ds, dp->index, mode, interface);
+}
+
+static void dsa_port_phylink_mac_link_up(struct phylink_config *config,
+					 struct phy_device *phydev,
+					 unsigned int mode,
+					 phy_interface_t interface,
+					 int speed, int duplex,
+					 bool tx_pause, bool rx_pause)
+{
+	struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->phylink_mac_link_up) {
+		if (ds->ops->adjust_link && phydev)
+			ds->ops->adjust_link(ds, dp->index, phydev);
+		return;
+	}
+
+	ds->ops->phylink_mac_link_up(ds, dp->index, mode, interface, phydev,
+				     speed, duplex, tx_pause, rx_pause);
+}
+
+static const struct phylink_mac_ops dsa_port_phylink_mac_ops = {
+	.validate = dsa_port_phylink_validate,
+	.mac_select_pcs = dsa_port_phylink_mac_select_pcs,
+	.mac_pcs_get_state = dsa_port_phylink_mac_pcs_get_state,
+	.mac_config = dsa_port_phylink_mac_config,
+	.mac_an_restart = dsa_port_phylink_mac_an_restart,
+	.mac_link_down = dsa_port_phylink_mac_link_down,
+	.mac_link_up = dsa_port_phylink_mac_link_up,
+};
+
+int dsa_port_phylink_create(struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+	phy_interface_t mode;
+	struct phylink *pl;
+	int err;
+
+	err = of_get_phy_mode(dp->dn, &mode);
+	if (err)
+		mode = PHY_INTERFACE_MODE_NA;
+
+	/* Presence of phylink_mac_link_state or phylink_mac_an_restart is
+	 * an indicator of a legacy phylink driver.
+	 */
+	if (ds->ops->phylink_mac_link_state ||
+	    ds->ops->phylink_mac_an_restart)
+		dp->pl_config.legacy_pre_march2020 = true;
+
+	if (ds->ops->phylink_get_caps)
+		ds->ops->phylink_get_caps(ds, dp->index, &dp->pl_config);
+
+	pl = phylink_create(&dp->pl_config, of_fwnode_handle(dp->dn),
+			    mode, &dsa_port_phylink_mac_ops);
+	if (IS_ERR(pl)) {
+		pr_err("error creating PHYLINK: %ld\n", PTR_ERR(pl));
+		return PTR_ERR(pl);
+	}
+
+	dp->pl = pl;
+
+	return 0;
+}
+
+void dsa_port_phylink_destroy(struct dsa_port *dp)
+{
+	phylink_destroy(dp->pl);
+	dp->pl = NULL;
+}
+
+static int dsa_shared_port_setup_phy_of(struct dsa_port *dp, bool enable)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct phy_device *phydev;
+	int port = dp->index;
+	int err = 0;
+
+	phydev = dsa_port_get_phy_device(dp);
+	if (!phydev)
+		return 0;
+
+	if (IS_ERR(phydev))
+		return PTR_ERR(phydev);
+
+	if (enable) {
+		err = genphy_resume(phydev);
+		if (err < 0)
+			goto err_put_dev;
+
+		err = genphy_read_status(phydev);
+		if (err < 0)
+			goto err_put_dev;
+	} else {
+		err = genphy_suspend(phydev);
+		if (err < 0)
+			goto err_put_dev;
+	}
+
+	if (ds->ops->adjust_link)
+		ds->ops->adjust_link(ds, port, phydev);
+
+	dev_dbg(ds->dev, "enabled port's phy: %s", phydev_name(phydev));
+
+err_put_dev:
+	put_device(&phydev->mdio.dev);
+	return err;
+}
+
+static int dsa_shared_port_fixed_link_register_of(struct dsa_port *dp)
+{
+	struct device_node *dn = dp->dn;
+	struct dsa_switch *ds = dp->ds;
+	struct phy_device *phydev;
+	int port = dp->index;
+	phy_interface_t mode;
+	int err;
+
+	err = of_phy_register_fixed_link(dn);
+	if (err) {
+		dev_err(ds->dev,
+			"failed to register the fixed PHY of port %d\n",
+			port);
+		return err;
+	}
+
+	phydev = of_phy_find_device(dn);
+
+	err = of_get_phy_mode(dn, &mode);
+	if (err)
+		mode = PHY_INTERFACE_MODE_NA;
+	phydev->interface = mode;
+
+	genphy_read_status(phydev);
+
+	if (ds->ops->adjust_link)
+		ds->ops->adjust_link(ds, port, phydev);
+
+	put_device(&phydev->mdio.dev);
+
+	return 0;
+}
+
+static int dsa_shared_port_phylink_register(struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct device_node *port_dn = dp->dn;
+	int err;
+
+	dp->pl_config.dev = ds->dev;
+	dp->pl_config.type = PHYLINK_DEV;
+
+	err = dsa_port_phylink_create(dp);
+	if (err)
+		return err;
+
+	err = phylink_of_phy_connect(dp->pl, port_dn, 0);
+	if (err && err != -ENODEV) {
+		pr_err("could not attach to PHY: %d\n", err);
+		goto err_phy_connect;
+	}
+
+	return 0;
+
+err_phy_connect:
+	dsa_port_phylink_destroy(dp);
+	return err;
+}
+
+/* During the initial DSA driver migration to OF, port nodes were sometimes
+ * added to device trees with no indication of how they should operate from a
+ * link management perspective (phy-handle, fixed-link, etc). Additionally, the
+ * phy-mode may be absent. The interpretation of these port OF nodes depends on
+ * their type.
+ *
+ * User ports with no phy-handle or fixed-link are expected to connect to an
+ * internal PHY located on the ds->slave_mii_bus at an MDIO address equal to
+ * the port number. This description is still actively supported.
+ *
+ * Shared (CPU and DSA) ports with no phy-handle or fixed-link are expected to
+ * operate at the maximum speed that their phy-mode is capable of. If the
+ * phy-mode is absent, they are expected to operate using the phy-mode
+ * supported by the port that gives the highest link speed. It is unspecified
+ * if the port should use flow control or not, half duplex or full duplex, or
+ * if the phy-mode is a SERDES link, whether in-band autoneg is expected to be
+ * enabled or not.
+ *
+ * In the latter case of shared ports, omitting the link management description
+ * from the firmware node is deprecated and strongly discouraged. DSA uses
+ * phylink, which rejects the firmware nodes of these ports for lacking
+ * required properties.
+ *
+ * For switches in this table, DSA will skip enforcing validation and will
+ * later omit registering a phylink instance for the shared ports, if they lack
+ * a fixed-link, a phy-handle, or a managed = "in-band-status" property.
+ * It becomes the responsibility of the driver to ensure that these ports
+ * operate at the maximum speed (whatever this means) and will interoperate
+ * with the DSA master or other cascade port, since phylink methods will not be
+ * invoked for them.
+ *
+ * If you are considering expanding this table for newly introduced switches,
+ * think again. It is OK to remove switches from this table if there aren't DT
+ * blobs in circulation which rely on defaulting the shared ports.
+ */
+static const char * const dsa_switches_apply_workarounds[] = {
+#if IS_ENABLED(CONFIG_NET_DSA_XRS700X)
+	"arrow,xrs7003e",
+	"arrow,xrs7003f",
+	"arrow,xrs7004e",
+	"arrow,xrs7004f",
+#endif
+#if IS_ENABLED(CONFIG_B53)
+	"brcm,bcm5325",
+	"brcm,bcm53115",
+	"brcm,bcm53125",
+	"brcm,bcm53128",
+	"brcm,bcm5365",
+	"brcm,bcm5389",
+	"brcm,bcm5395",
+	"brcm,bcm5397",
+	"brcm,bcm5398",
+	"brcm,bcm53010-srab",
+	"brcm,bcm53011-srab",
+	"brcm,bcm53012-srab",
+	"brcm,bcm53018-srab",
+	"brcm,bcm53019-srab",
+	"brcm,bcm5301x-srab",
+	"brcm,bcm11360-srab",
+	"brcm,bcm58522-srab",
+	"brcm,bcm58525-srab",
+	"brcm,bcm58535-srab",
+	"brcm,bcm58622-srab",
+	"brcm,bcm58623-srab",
+	"brcm,bcm58625-srab",
+	"brcm,bcm88312-srab",
+	"brcm,cygnus-srab",
+	"brcm,nsp-srab",
+	"brcm,omega-srab",
+	"brcm,bcm3384-switch",
+	"brcm,bcm6328-switch",
+	"brcm,bcm6368-switch",
+	"brcm,bcm63xx-switch",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_BCM_SF2)
+	"brcm,bcm7445-switch-v4.0",
+	"brcm,bcm7278-switch-v4.0",
+	"brcm,bcm7278-switch-v4.8",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_LANTIQ_GSWIP)
+	"lantiq,xrx200-gswip",
+	"lantiq,xrx300-gswip",
+	"lantiq,xrx330-gswip",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_MV88E6060)
+	"marvell,mv88e6060",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_MV88E6XXX)
+	"marvell,mv88e6085",
+	"marvell,mv88e6190",
+	"marvell,mv88e6250",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_MICROCHIP_KSZ_COMMON)
+	"microchip,ksz8765",
+	"microchip,ksz8794",
+	"microchip,ksz8795",
+	"microchip,ksz8863",
+	"microchip,ksz8873",
+	"microchip,ksz9477",
+	"microchip,ksz9897",
+	"microchip,ksz9893",
+	"microchip,ksz9563",
+	"microchip,ksz8563",
+	"microchip,ksz9567",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_SMSC_LAN9303_MDIO)
+	"smsc,lan9303-mdio",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_SMSC_LAN9303_I2C)
+	"smsc,lan9303-i2c",
+#endif
+	NULL,
+};
+
+static void dsa_shared_port_validate_of(struct dsa_port *dp,
+					bool *missing_phy_mode,
+					bool *missing_link_description)
+{
+	struct device_node *dn = dp->dn, *phy_np;
+	struct dsa_switch *ds = dp->ds;
+	phy_interface_t mode;
+
+	*missing_phy_mode = false;
+	*missing_link_description = false;
+
+	if (of_get_phy_mode(dn, &mode)) {
+		*missing_phy_mode = true;
+		dev_err(ds->dev,
+			"OF node %pOF of %s port %d lacks the required \"phy-mode\" property\n",
+			dn, dsa_port_is_cpu(dp) ? "CPU" : "DSA", dp->index);
+	}
+
+	/* Note: of_phy_is_fixed_link() also returns true for
+	 * managed = "in-band-status"
+	 */
+	if (of_phy_is_fixed_link(dn))
+		return;
+
+	phy_np = of_parse_phandle(dn, "phy-handle", 0);
+	if (phy_np) {
+		of_node_put(phy_np);
+		return;
+	}
+
+	*missing_link_description = true;
+
+	dev_err(ds->dev,
+		"OF node %pOF of %s port %d lacks the required \"phy-handle\", \"fixed-link\" or \"managed\" properties\n",
+		dn, dsa_port_is_cpu(dp) ? "CPU" : "DSA", dp->index);
+}
+
+int dsa_shared_port_link_register_of(struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+	bool missing_link_description;
+	bool missing_phy_mode;
+	int port = dp->index;
+
+	dsa_shared_port_validate_of(dp, &missing_phy_mode,
+				    &missing_link_description);
+
+	if ((missing_phy_mode || missing_link_description) &&
+	    !of_device_compatible_match(ds->dev->of_node,
+					dsa_switches_apply_workarounds))
+		return -EINVAL;
+
+	if (!ds->ops->adjust_link) {
+		if (missing_link_description) {
+			dev_warn(ds->dev,
+				 "Skipping phylink registration for %s port %d\n",
+				 dsa_port_is_cpu(dp) ? "CPU" : "DSA", dp->index);
+		} else {
+			if (ds->ops->phylink_mac_link_down)
+				ds->ops->phylink_mac_link_down(ds, port,
+					MLO_AN_FIXED, PHY_INTERFACE_MODE_NA);
+
+			return dsa_shared_port_phylink_register(dp);
+		}
+		return 0;
+	}
+
+	dev_warn(ds->dev,
+		 "Using legacy PHYLIB callbacks. Please migrate to PHYLINK!\n");
+
+	if (of_phy_is_fixed_link(dp->dn))
+		return dsa_shared_port_fixed_link_register_of(dp);
+	else
+		return dsa_shared_port_setup_phy_of(dp, true);
+}
+
+void dsa_shared_port_link_unregister_of(struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->adjust_link && dp->pl) {
+		rtnl_lock();
+		phylink_disconnect_phy(dp->pl);
+		rtnl_unlock();
+		dsa_port_phylink_destroy(dp);
+		return;
+	}
+
+	if (of_phy_is_fixed_link(dp->dn))
+		of_phy_deregister_fixed_link(dp->dn);
+	else
+		dsa_shared_port_setup_phy_of(dp, false);
+}
+
+int dsa_port_hsr_join(struct dsa_port *dp, struct net_device *hsr)
+{
+	struct dsa_switch *ds = dp->ds;
+	int err;
+
+	if (!ds->ops->port_hsr_join)
+		return -EOPNOTSUPP;
+
+	dp->hsr_dev = hsr;
+
+	err = ds->ops->port_hsr_join(ds, dp->index, hsr);
+	if (err)
+		dp->hsr_dev = NULL;
+
+	return err;
+}
+
+void dsa_port_hsr_leave(struct dsa_port *dp, struct net_device *hsr)
+{
+	struct dsa_switch *ds = dp->ds;
+	int err;
+
+	dp->hsr_dev = NULL;
+
+	if (ds->ops->port_hsr_leave) {
+		err = ds->ops->port_hsr_leave(ds, dp->index, hsr);
+		if (err)
+			dev_err(dp->ds->dev,
+				"port %d failed to leave HSR %s: %pe\n",
+				dp->index, hsr->name, ERR_PTR(err));
+	}
+}
+
+int dsa_port_tag_8021q_vlan_add(struct dsa_port *dp, u16 vid, bool broadcast)
+{
+	struct dsa_notifier_tag_8021q_vlan_info info = {
+		.dp = dp,
+		.vid = vid,
+	};
+
+	if (broadcast)
+		return dsa_broadcast(DSA_NOTIFIER_TAG_8021Q_VLAN_ADD, &info);
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_TAG_8021Q_VLAN_ADD, &info);
+}
+
+void dsa_port_tag_8021q_vlan_del(struct dsa_port *dp, u16 vid, bool broadcast)
+{
+	struct dsa_notifier_tag_8021q_vlan_info info = {
+		.dp = dp,
+		.vid = vid,
+	};
+	int err;
+
+	if (broadcast)
+		err = dsa_broadcast(DSA_NOTIFIER_TAG_8021Q_VLAN_DEL, &info);
+	else
+		err = dsa_port_notify(dp, DSA_NOTIFIER_TAG_8021Q_VLAN_DEL, &info);
+	if (err)
+		dev_err(dp->ds->dev,
+			"port %d failed to notify tag_8021q VLAN %d deletion: %pe\n",
+			dp->index, vid, ERR_PTR(err));
+}
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
new file mode 100644
index 000000000..5fe075bf4
--- /dev/null
+++ b/net/dsa/slave.c
@@ -0,0 +1,3491 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * net/dsa/slave.c - Slave device handling
+ * Copyright (c) 2008-2009 Marvell Semiconductor
+ */
+
+#include <linux/list.h>
+#include <linux/etherdevice.h>
+#include <linux/netdevice.h>
+#include <linux/phy.h>
+#include <linux/phy_fixed.h>
+#include <linux/phylink.h>
+#include <linux/of_net.h>
+#include <linux/of_mdio.h>
+#include <linux/mdio.h>
+#include <net/rtnetlink.h>
+#include <net/pkt_cls.h>
+#include <net/selftests.h>
+#include <net/tc_act/tc_mirred.h>
+#include <linux/if_bridge.h>
+#include <linux/if_hsr.h>
+#include <net/dcbnl.h>
+#include <linux/netpoll.h>
+
+#include "dsa_priv.h"
+
+static void dsa_slave_standalone_event_work(struct work_struct *work)
+{
+	struct dsa_standalone_event_work *standalone_work =
+		container_of(work, struct dsa_standalone_event_work, work);
+	const unsigned char *addr = standalone_work->addr;
+	struct net_device *dev = standalone_work->dev;
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_mdb mdb;
+	struct dsa_switch *ds = dp->ds;
+	u16 vid = standalone_work->vid;
+	int err;
+
+	switch (standalone_work->event) {
+	case DSA_UC_ADD:
+		err = dsa_port_standalone_host_fdb_add(dp, addr, vid);
+		if (err) {
+			dev_err(ds->dev,
+				"port %d failed to add %pM vid %d to fdb: %d\n",
+				dp->index, addr, vid, err);
+			break;
+		}
+		break;
+
+	case DSA_UC_DEL:
+		err = dsa_port_standalone_host_fdb_del(dp, addr, vid);
+		if (err) {
+			dev_err(ds->dev,
+				"port %d failed to delete %pM vid %d from fdb: %d\n",
+				dp->index, addr, vid, err);
+		}
+
+		break;
+	case DSA_MC_ADD:
+		ether_addr_copy(mdb.addr, addr);
+		mdb.vid = vid;
+
+		err = dsa_port_standalone_host_mdb_add(dp, &mdb);
+		if (err) {
+			dev_err(ds->dev,
+				"port %d failed to add %pM vid %d to mdb: %d\n",
+				dp->index, addr, vid, err);
+			break;
+		}
+		break;
+	case DSA_MC_DEL:
+		ether_addr_copy(mdb.addr, addr);
+		mdb.vid = vid;
+
+		err = dsa_port_standalone_host_mdb_del(dp, &mdb);
+		if (err) {
+			dev_err(ds->dev,
+				"port %d failed to delete %pM vid %d from mdb: %d\n",
+				dp->index, addr, vid, err);
+		}
+
+		break;
+	}
+
+	kfree(standalone_work);
+}
+
+static int dsa_slave_schedule_standalone_work(struct net_device *dev,
+					      enum dsa_standalone_event event,
+					      const unsigned char *addr,
+					      u16 vid)
+{
+	struct dsa_standalone_event_work *standalone_work;
+
+	standalone_work = kzalloc(sizeof(*standalone_work), GFP_ATOMIC);
+	if (!standalone_work)
+		return -ENOMEM;
+
+	INIT_WORK(&standalone_work->work, dsa_slave_standalone_event_work);
+	standalone_work->event = event;
+	standalone_work->dev = dev;
+
+	ether_addr_copy(standalone_work->addr, addr);
+	standalone_work->vid = vid;
+
+	dsa_schedule_work(&standalone_work->work);
+
+	return 0;
+}
+
+static int dsa_slave_sync_uc(struct net_device *dev,
+			     const unsigned char *addr)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	dev_uc_add(master, addr);
+
+	if (!dsa_switch_supports_uc_filtering(dp->ds))
+		return 0;
+
+	return dsa_slave_schedule_standalone_work(dev, DSA_UC_ADD, addr, 0);
+}
+
+static int dsa_slave_unsync_uc(struct net_device *dev,
+			       const unsigned char *addr)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	dev_uc_del(master, addr);
+
+	if (!dsa_switch_supports_uc_filtering(dp->ds))
+		return 0;
+
+	return dsa_slave_schedule_standalone_work(dev, DSA_UC_DEL, addr, 0);
+}
+
+static int dsa_slave_sync_mc(struct net_device *dev,
+			     const unsigned char *addr)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	dev_mc_add(master, addr);
+
+	if (!dsa_switch_supports_mc_filtering(dp->ds))
+		return 0;
+
+	return dsa_slave_schedule_standalone_work(dev, DSA_MC_ADD, addr, 0);
+}
+
+static int dsa_slave_unsync_mc(struct net_device *dev,
+			       const unsigned char *addr)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	dev_mc_del(master, addr);
+
+	if (!dsa_switch_supports_mc_filtering(dp->ds))
+		return 0;
+
+	return dsa_slave_schedule_standalone_work(dev, DSA_MC_DEL, addr, 0);
+}
+
+void dsa_slave_sync_ha(struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	struct netdev_hw_addr *ha;
+
+	netif_addr_lock_bh(dev);
+
+	netdev_for_each_synced_mc_addr(ha, dev)
+		dsa_slave_sync_mc(dev, ha->addr);
+
+	netdev_for_each_synced_uc_addr(ha, dev)
+		dsa_slave_sync_uc(dev, ha->addr);
+
+	netif_addr_unlock_bh(dev);
+
+	if (dsa_switch_supports_uc_filtering(ds) ||
+	    dsa_switch_supports_mc_filtering(ds))
+		dsa_flush_workqueue();
+}
+
+void dsa_slave_unsync_ha(struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	struct netdev_hw_addr *ha;
+
+	netif_addr_lock_bh(dev);
+
+	netdev_for_each_synced_uc_addr(ha, dev)
+		dsa_slave_unsync_uc(dev, ha->addr);
+
+	netdev_for_each_synced_mc_addr(ha, dev)
+		dsa_slave_unsync_mc(dev, ha->addr);
+
+	netif_addr_unlock_bh(dev);
+
+	if (dsa_switch_supports_uc_filtering(ds) ||
+	    dsa_switch_supports_mc_filtering(ds))
+		dsa_flush_workqueue();
+}
+
+/* slave mii_bus handling ***************************************************/
+static int dsa_slave_phy_read(struct mii_bus *bus, int addr, int reg)
+{
+	struct dsa_switch *ds = bus->priv;
+
+	if (ds->phys_mii_mask & (1 << addr))
+		return ds->ops->phy_read(ds, addr, reg);
+
+	return 0xffff;
+}
+
+static int dsa_slave_phy_write(struct mii_bus *bus, int addr, int reg, u16 val)
+{
+	struct dsa_switch *ds = bus->priv;
+
+	if (ds->phys_mii_mask & (1 << addr))
+		return ds->ops->phy_write(ds, addr, reg, val);
+
+	return 0;
+}
+
+void dsa_slave_mii_bus_init(struct dsa_switch *ds)
+{
+	ds->slave_mii_bus->priv = (void *)ds;
+	ds->slave_mii_bus->name = "dsa slave smi";
+	ds->slave_mii_bus->read = dsa_slave_phy_read;
+	ds->slave_mii_bus->write = dsa_slave_phy_write;
+	snprintf(ds->slave_mii_bus->id, MII_BUS_ID_SIZE, "dsa-%d.%d",
+		 ds->dst->index, ds->index);
+	ds->slave_mii_bus->parent = ds->dev;
+	ds->slave_mii_bus->phy_mask = ~ds->phys_mii_mask;
+}
+
+
+/* slave device handling ****************************************************/
+static int dsa_slave_get_iflink(const struct net_device *dev)
+{
+	return dsa_slave_to_master(dev)->ifindex;
+}
+
+static int dsa_slave_open(struct net_device *dev)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	int err;
+
+	err = dev_open(master, NULL);
+	if (err < 0) {
+		netdev_err(dev, "failed to open master %s\n", master->name);
+		goto out;
+	}
+
+	if (dsa_switch_supports_uc_filtering(ds)) {
+		err = dsa_port_standalone_host_fdb_add(dp, dev->dev_addr, 0);
+		if (err)
+			goto out;
+	}
+
+	if (!ether_addr_equal(dev->dev_addr, master->dev_addr)) {
+		err = dev_uc_add(master, dev->dev_addr);
+		if (err < 0)
+			goto del_host_addr;
+	}
+
+	err = dsa_port_enable_rt(dp, dev->phydev);
+	if (err)
+		goto del_unicast;
+
+	return 0;
+
+del_unicast:
+	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
+		dev_uc_del(master, dev->dev_addr);
+del_host_addr:
+	if (dsa_switch_supports_uc_filtering(ds))
+		dsa_port_standalone_host_fdb_del(dp, dev->dev_addr, 0);
+out:
+	return err;
+}
+
+static int dsa_slave_close(struct net_device *dev)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	dsa_port_disable_rt(dp);
+
+	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
+		dev_uc_del(master, dev->dev_addr);
+
+	if (dsa_switch_supports_uc_filtering(ds))
+		dsa_port_standalone_host_fdb_del(dp, dev->dev_addr, 0);
+
+	return 0;
+}
+
+static void dsa_slave_manage_host_flood(struct net_device *dev)
+{
+	bool mc = dev->flags & (IFF_PROMISC | IFF_ALLMULTI);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	bool uc = dev->flags & IFF_PROMISC;
+
+	dsa_port_set_host_flood(dp, uc, mc);
+}
+
+static void dsa_slave_change_rx_flags(struct net_device *dev, int change)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (change & IFF_ALLMULTI)
+		dev_set_allmulti(master,
+				 dev->flags & IFF_ALLMULTI ? 1 : -1);
+	if (change & IFF_PROMISC)
+		dev_set_promiscuity(master,
+				    dev->flags & IFF_PROMISC ? 1 : -1);
+
+	if (dsa_switch_supports_uc_filtering(ds) &&
+	    dsa_switch_supports_mc_filtering(ds))
+		dsa_slave_manage_host_flood(dev);
+}
+
+static void dsa_slave_set_rx_mode(struct net_device *dev)
+{
+	__dev_mc_sync(dev, dsa_slave_sync_mc, dsa_slave_unsync_mc);
+	__dev_uc_sync(dev, dsa_slave_sync_uc, dsa_slave_unsync_uc);
+}
+
+static int dsa_slave_set_mac_address(struct net_device *dev, void *a)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	struct sockaddr *addr = a;
+	int err;
+
+	if (!is_valid_ether_addr(addr->sa_data))
+		return -EADDRNOTAVAIL;
+
+	/* If the port is down, the address isn't synced yet to hardware or
+	 * to the DSA master, so there is nothing to change.
+	 */
+	if (!(dev->flags & IFF_UP))
+		goto out_change_dev_addr;
+
+	if (dsa_switch_supports_uc_filtering(ds)) {
+		err = dsa_port_standalone_host_fdb_add(dp, addr->sa_data, 0);
+		if (err)
+			return err;
+	}
+
+	if (!ether_addr_equal(addr->sa_data, master->dev_addr)) {
+		err = dev_uc_add(master, addr->sa_data);
+		if (err < 0)
+			goto del_unicast;
+	}
+
+	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
+		dev_uc_del(master, dev->dev_addr);
+
+	if (dsa_switch_supports_uc_filtering(ds))
+		dsa_port_standalone_host_fdb_del(dp, dev->dev_addr, 0);
+
+out_change_dev_addr:
+	eth_hw_addr_set(dev, addr->sa_data);
+
+	return 0;
+
+del_unicast:
+	if (dsa_switch_supports_uc_filtering(ds))
+		dsa_port_standalone_host_fdb_del(dp, addr->sa_data, 0);
+
+	return err;
+}
+
+struct dsa_slave_dump_ctx {
+	struct net_device *dev;
+	struct sk_buff *skb;
+	struct netlink_callback *cb;
+	int idx;
+};
+
+static int
+dsa_slave_port_fdb_do_dump(const unsigned char *addr, u16 vid,
+			   bool is_static, void *data)
+{
+	struct dsa_slave_dump_ctx *dump = data;
+	u32 portid = NETLINK_CB(dump->cb->skb).portid;
+	u32 seq = dump->cb->nlh->nlmsg_seq;
+	struct nlmsghdr *nlh;
+	struct ndmsg *ndm;
+
+	if (dump->idx < dump->cb->args[2])
+		goto skip;
+
+	nlh = nlmsg_put(dump->skb, portid, seq, RTM_NEWNEIGH,
+			sizeof(*ndm), NLM_F_MULTI);
+	if (!nlh)
+		return -EMSGSIZE;
+
+	ndm = nlmsg_data(nlh);
+	ndm->ndm_family  = AF_BRIDGE;
+	ndm->ndm_pad1    = 0;
+	ndm->ndm_pad2    = 0;
+	ndm->ndm_flags   = NTF_SELF;
+	ndm->ndm_type    = 0;
+	ndm->ndm_ifindex = dump->dev->ifindex;
+	ndm->ndm_state   = is_static ? NUD_NOARP : NUD_REACHABLE;
+
+	if (nla_put(dump->skb, NDA_LLADDR, ETH_ALEN, addr))
+		goto nla_put_failure;
+
+	if (vid && nla_put_u16(dump->skb, NDA_VLAN, vid))
+		goto nla_put_failure;
+
+	nlmsg_end(dump->skb, nlh);
+
+skip:
+	dump->idx++;
+	return 0;
+
+nla_put_failure:
+	nlmsg_cancel(dump->skb, nlh);
+	return -EMSGSIZE;
+}
+
+static int
+dsa_slave_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb,
+		   struct net_device *dev, struct net_device *filter_dev,
+		   int *idx)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_slave_dump_ctx dump = {
+		.dev = dev,
+		.skb = skb,
+		.cb = cb,
+		.idx = *idx,
+	};
+	int err;
+
+	err = dsa_port_fdb_dump(dp, dsa_slave_port_fdb_do_dump, &dump);
+	*idx = dump.idx;
+
+	return err;
+}
+
+static int dsa_slave_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct dsa_switch *ds = p->dp->ds;
+	int port = p->dp->index;
+
+	/* Pass through to switch driver if it supports timestamping */
+	switch (cmd) {
+	case SIOCGHWTSTAMP:
+		if (ds->ops->port_hwtstamp_get)
+			return ds->ops->port_hwtstamp_get(ds, port, ifr);
+		break;
+	case SIOCSHWTSTAMP:
+		if (ds->ops->port_hwtstamp_set)
+			return ds->ops->port_hwtstamp_set(ds, port, ifr);
+		break;
+	}
+
+	return phylink_mii_ioctl(p->dp->pl, ifr, cmd);
+}
+
+static int dsa_slave_port_attr_set(struct net_device *dev, const void *ctx,
+				   const struct switchdev_attr *attr,
+				   struct netlink_ext_ack *extack)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	int ret;
+
+	if (ctx && ctx != dp)
+		return 0;
+
+	switch (attr->id) {
+	case SWITCHDEV_ATTR_ID_PORT_STP_STATE:
+		if (!dsa_port_offloads_bridge_port(dp, attr->orig_dev))
+			return -EOPNOTSUPP;
+
+		ret = dsa_port_set_state(dp, attr->u.stp_state, true);
+		break;
+	case SWITCHDEV_ATTR_ID_PORT_MST_STATE:
+		if (!dsa_port_offloads_bridge_port(dp, attr->orig_dev))
+			return -EOPNOTSUPP;
+
+		ret = dsa_port_set_mst_state(dp, &attr->u.mst_state, extack);
+		break;
+	case SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING:
+		if (!dsa_port_offloads_bridge_dev(dp, attr->orig_dev))
+			return -EOPNOTSUPP;
+
+		ret = dsa_port_vlan_filtering(dp, attr->u.vlan_filtering,
+					      extack);
+		break;
+	case SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME:
+		if (!dsa_port_offloads_bridge_dev(dp, attr->orig_dev))
+			return -EOPNOTSUPP;
+
+		ret = dsa_port_ageing_time(dp, attr->u.ageing_time);
+		break;
+	case SWITCHDEV_ATTR_ID_BRIDGE_MST:
+		if (!dsa_port_offloads_bridge_dev(dp, attr->orig_dev))
+			return -EOPNOTSUPP;
+
+		ret = dsa_port_mst_enable(dp, attr->u.mst, extack);
+		break;
+	case SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS:
+		if (!dsa_port_offloads_bridge_port(dp, attr->orig_dev))
+			return -EOPNOTSUPP;
+
+		ret = dsa_port_pre_bridge_flags(dp, attr->u.brport_flags,
+						extack);
+		break;
+	case SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS:
+		if (!dsa_port_offloads_bridge_port(dp, attr->orig_dev))
+			return -EOPNOTSUPP;
+
+		ret = dsa_port_bridge_flags(dp, attr->u.brport_flags, extack);
+		break;
+	case SWITCHDEV_ATTR_ID_VLAN_MSTI:
+		if (!dsa_port_offloads_bridge_dev(dp, attr->orig_dev))
+			return -EOPNOTSUPP;
+
+		ret = dsa_port_vlan_msti(dp, &attr->u.vlan_msti);
+		break;
+	default:
+		ret = -EOPNOTSUPP;
+		break;
+	}
+
+	return ret;
+}
+
+/* Must be called under rcu_read_lock() */
+static int
+dsa_slave_vlan_check_for_8021q_uppers(struct net_device *slave,
+				      const struct switchdev_obj_port_vlan *vlan)
+{
+	struct net_device *upper_dev;
+	struct list_head *iter;
+
+	netdev_for_each_upper_dev_rcu(slave, upper_dev, iter) {
+		u16 vid;
+
+		if (!is_vlan_dev(upper_dev))
+			continue;
+
+		vid = vlan_dev_vlan_id(upper_dev);
+		if (vid == vlan->vid)
+			return -EBUSY;
+	}
+
+	return 0;
+}
+
+static int dsa_slave_vlan_add(struct net_device *dev,
+			      const struct switchdev_obj *obj,
+			      struct netlink_ext_ack *extack)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_vlan *vlan;
+	int err;
+
+	if (dsa_port_skip_vlan_configuration(dp)) {
+		NL_SET_ERR_MSG_MOD(extack, "skipping configuration of VLAN");
+		return 0;
+	}
+
+	vlan = SWITCHDEV_OBJ_PORT_VLAN(obj);
+
+	/* Deny adding a bridge VLAN when there is already an 802.1Q upper with
+	 * the same VID.
+	 */
+	if (br_vlan_enabled(dsa_port_bridge_dev_get(dp))) {
+		rcu_read_lock();
+		err = dsa_slave_vlan_check_for_8021q_uppers(dev, vlan);
+		rcu_read_unlock();
+		if (err) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "Port already has a VLAN upper with this VID");
+			return err;
+		}
+	}
+
+	return dsa_port_vlan_add(dp, vlan, extack);
+}
+
+/* Offload a VLAN installed on the bridge or on a foreign interface by
+ * installing it as a VLAN towards the CPU port.
+ */
+static int dsa_slave_host_vlan_add(struct net_device *dev,
+				   const struct switchdev_obj *obj,
+				   struct netlink_ext_ack *extack)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_vlan vlan;
+
+	/* Do nothing if this is a software bridge */
+	if (!dp->bridge)
+		return -EOPNOTSUPP;
+
+	if (dsa_port_skip_vlan_configuration(dp)) {
+		NL_SET_ERR_MSG_MOD(extack, "skipping configuration of VLAN");
+		return 0;
+	}
+
+	vlan = *SWITCHDEV_OBJ_PORT_VLAN(obj);
+
+	/* Even though drivers often handle CPU membership in special ways,
+	 * it doesn't make sense to program a PVID, so clear this flag.
+	 */
+	vlan.flags &= ~BRIDGE_VLAN_INFO_PVID;
+
+	return dsa_port_host_vlan_add(dp, &vlan, extack);
+}
+
+static int dsa_slave_port_obj_add(struct net_device *dev, const void *ctx,
+				  const struct switchdev_obj *obj,
+				  struct netlink_ext_ack *extack)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	int err;
+
+	if (ctx && ctx != dp)
+		return 0;
+
+	switch (obj->id) {
+	case SWITCHDEV_OBJ_ID_PORT_MDB:
+		if (!dsa_port_offloads_bridge_port(dp, obj->orig_dev))
+			return -EOPNOTSUPP;
+
+		err = dsa_port_mdb_add(dp, SWITCHDEV_OBJ_PORT_MDB(obj));
+		break;
+	case SWITCHDEV_OBJ_ID_HOST_MDB:
+		if (!dsa_port_offloads_bridge_dev(dp, obj->orig_dev))
+			return -EOPNOTSUPP;
+
+		err = dsa_port_bridge_host_mdb_add(dp, SWITCHDEV_OBJ_PORT_MDB(obj));
+		break;
+	case SWITCHDEV_OBJ_ID_PORT_VLAN:
+		if (dsa_port_offloads_bridge_port(dp, obj->orig_dev))
+			err = dsa_slave_vlan_add(dev, obj, extack);
+		else
+			err = dsa_slave_host_vlan_add(dev, obj, extack);
+		break;
+	case SWITCHDEV_OBJ_ID_MRP:
+		if (!dsa_port_offloads_bridge_dev(dp, obj->orig_dev))
+			return -EOPNOTSUPP;
+
+		err = dsa_port_mrp_add(dp, SWITCHDEV_OBJ_MRP(obj));
+		break;
+	case SWITCHDEV_OBJ_ID_RING_ROLE_MRP:
+		if (!dsa_port_offloads_bridge_dev(dp, obj->orig_dev))
+			return -EOPNOTSUPP;
+
+		err = dsa_port_mrp_add_ring_role(dp,
+						 SWITCHDEV_OBJ_RING_ROLE_MRP(obj));
+		break;
+	default:
+		err = -EOPNOTSUPP;
+		break;
+	}
+
+	return err;
+}
+
+static int dsa_slave_vlan_del(struct net_device *dev,
+			      const struct switchdev_obj *obj)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_vlan *vlan;
+
+	if (dsa_port_skip_vlan_configuration(dp))
+		return 0;
+
+	vlan = SWITCHDEV_OBJ_PORT_VLAN(obj);
+
+	return dsa_port_vlan_del(dp, vlan);
+}
+
+static int dsa_slave_host_vlan_del(struct net_device *dev,
+				   const struct switchdev_obj *obj)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_vlan *vlan;
+
+	/* Do nothing if this is a software bridge */
+	if (!dp->bridge)
+		return -EOPNOTSUPP;
+
+	if (dsa_port_skip_vlan_configuration(dp))
+		return 0;
+
+	vlan = SWITCHDEV_OBJ_PORT_VLAN(obj);
+
+	return dsa_port_host_vlan_del(dp, vlan);
+}
+
+static int dsa_slave_port_obj_del(struct net_device *dev, const void *ctx,
+				  const struct switchdev_obj *obj)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	int err;
+
+	if (ctx && ctx != dp)
+		return 0;
+
+	switch (obj->id) {
+	case SWITCHDEV_OBJ_ID_PORT_MDB:
+		if (!dsa_port_offloads_bridge_port(dp, obj->orig_dev))
+			return -EOPNOTSUPP;
+
+		err = dsa_port_mdb_del(dp, SWITCHDEV_OBJ_PORT_MDB(obj));
+		break;
+	case SWITCHDEV_OBJ_ID_HOST_MDB:
+		if (!dsa_port_offloads_bridge_dev(dp, obj->orig_dev))
+			return -EOPNOTSUPP;
+
+		err = dsa_port_bridge_host_mdb_del(dp, SWITCHDEV_OBJ_PORT_MDB(obj));
+		break;
+	case SWITCHDEV_OBJ_ID_PORT_VLAN:
+		if (dsa_port_offloads_bridge_port(dp, obj->orig_dev))
+			err = dsa_slave_vlan_del(dev, obj);
+		else
+			err = dsa_slave_host_vlan_del(dev, obj);
+		break;
+	case SWITCHDEV_OBJ_ID_MRP:
+		if (!dsa_port_offloads_bridge_dev(dp, obj->orig_dev))
+			return -EOPNOTSUPP;
+
+		err = dsa_port_mrp_del(dp, SWITCHDEV_OBJ_MRP(obj));
+		break;
+	case SWITCHDEV_OBJ_ID_RING_ROLE_MRP:
+		if (!dsa_port_offloads_bridge_dev(dp, obj->orig_dev))
+			return -EOPNOTSUPP;
+
+		err = dsa_port_mrp_del_ring_role(dp,
+						 SWITCHDEV_OBJ_RING_ROLE_MRP(obj));
+		break;
+	default:
+		err = -EOPNOTSUPP;
+		break;
+	}
+
+	return err;
+}
+
+static inline netdev_tx_t dsa_slave_netpoll_send_skb(struct net_device *dev,
+						     struct sk_buff *skb)
+{
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	struct dsa_slave_priv *p = netdev_priv(dev);
+
+	return netpoll_send_skb(p->netpoll, skb);
+#else
+	BUG();
+	return NETDEV_TX_OK;
+#endif
+}
+
+static void dsa_skb_tx_timestamp(struct dsa_slave_priv *p,
+				 struct sk_buff *skb)
+{
+	struct dsa_switch *ds = p->dp->ds;
+
+	if (!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP))
+		return;
+
+	if (!ds->ops->port_txtstamp)
+		return;
+
+	ds->ops->port_txtstamp(ds, p->dp->index, skb);
+}
+
+netdev_tx_t dsa_enqueue_skb(struct sk_buff *skb, struct net_device *dev)
+{
+	/* SKB for netpoll still need to be mangled with the protocol-specific
+	 * tag to be successfully transmitted
+	 */
+	if (unlikely(netpoll_tx_running(dev)))
+		return dsa_slave_netpoll_send_skb(dev, skb);
+
+	/* Queue the SKB for transmission on the parent interface, but
+	 * do not modify its EtherType
+	 */
+	skb->dev = dsa_slave_to_master(dev);
+	dev_queue_xmit(skb);
+
+	return NETDEV_TX_OK;
+}
+EXPORT_SYMBOL_GPL(dsa_enqueue_skb);
+
+static int dsa_realloc_skb(struct sk_buff *skb, struct net_device *dev)
+{
+	int needed_headroom = dev->needed_headroom;
+	int needed_tailroom = dev->needed_tailroom;
+
+	/* For tail taggers, we need to pad short frames ourselves, to ensure
+	 * that the tail tag does not fail at its role of being at the end of
+	 * the packet, once the master interface pads the frame. Account for
+	 * that pad length here, and pad later.
+	 */
+	if (unlikely(needed_tailroom && skb->len < ETH_ZLEN))
+		needed_tailroom += ETH_ZLEN - skb->len;
+	/* skb_headroom() returns unsigned int... */
+	needed_headroom = max_t(int, needed_headroom - skb_headroom(skb), 0);
+	needed_tailroom = max_t(int, needed_tailroom - skb_tailroom(skb), 0);
+
+	if (likely(!needed_headroom && !needed_tailroom && !skb_cloned(skb)))
+		/* No reallocation needed, yay! */
+		return 0;
+
+	return pskb_expand_head(skb, needed_headroom, needed_tailroom,
+				GFP_ATOMIC);
+}
+
+static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct sk_buff *nskb;
+
+	dev_sw_netstats_tx_add(dev, 1, skb->len);
+
+	memset(skb->cb, 0, sizeof(skb->cb));
+
+	/* Handle tx timestamp if any */
+	dsa_skb_tx_timestamp(p, skb);
+
+	if (dsa_realloc_skb(skb, dev)) {
+		dev_kfree_skb_any(skb);
+		return NETDEV_TX_OK;
+	}
+
+	/* needed_tailroom should still be 'warm' in the cache line from
+	 * dsa_realloc_skb(), which has also ensured that padding is safe.
+	 */
+	if (dev->needed_tailroom)
+		eth_skb_pad(skb);
+
+	/* Transmit function may have to reallocate the original SKB,
+	 * in which case it must have freed it. Only free it here on error.
+	 */
+	nskb = p->xmit(skb, dev);
+	if (!nskb) {
+		kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
+
+	return dsa_enqueue_skb(nskb, dev);
+}
+
+/* ethtool operations *******************************************************/
+
+static void dsa_slave_get_drvinfo(struct net_device *dev,
+				  struct ethtool_drvinfo *drvinfo)
+{
+	strscpy(drvinfo->driver, "dsa", sizeof(drvinfo->driver));
+	strscpy(drvinfo->fw_version, "N/A", sizeof(drvinfo->fw_version));
+	strscpy(drvinfo->bus_info, "platform", sizeof(drvinfo->bus_info));
+}
+
+static int dsa_slave_get_regs_len(struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_regs_len)
+		return ds->ops->get_regs_len(ds, dp->index);
+
+	return -EOPNOTSUPP;
+}
+
+static void
+dsa_slave_get_regs(struct net_device *dev, struct ethtool_regs *regs, void *_p)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_regs)
+		ds->ops->get_regs(ds, dp->index, regs, _p);
+}
+
+static int dsa_slave_nway_reset(struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return phylink_ethtool_nway_reset(dp->pl);
+}
+
+static int dsa_slave_get_eeprom_len(struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->cd && ds->cd->eeprom_len)
+		return ds->cd->eeprom_len;
+
+	if (ds->ops->get_eeprom_len)
+		return ds->ops->get_eeprom_len(ds);
+
+	return 0;
+}
+
+static int dsa_slave_get_eeprom(struct net_device *dev,
+				struct ethtool_eeprom *eeprom, u8 *data)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_eeprom)
+		return ds->ops->get_eeprom(ds, eeprom, data);
+
+	return -EOPNOTSUPP;
+}
+
+static int dsa_slave_set_eeprom(struct net_device *dev,
+				struct ethtool_eeprom *eeprom, u8 *data)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->set_eeprom)
+		return ds->ops->set_eeprom(ds, eeprom, data);
+
+	return -EOPNOTSUPP;
+}
+
+static void dsa_slave_get_strings(struct net_device *dev,
+				  uint32_t stringset, uint8_t *data)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (stringset == ETH_SS_STATS) {
+		int len = ETH_GSTRING_LEN;
+
+		strncpy(data, "tx_packets", len);
+		strncpy(data + len, "tx_bytes", len);
+		strncpy(data + 2 * len, "rx_packets", len);
+		strncpy(data + 3 * len, "rx_bytes", len);
+		if (ds->ops->get_strings)
+			ds->ops->get_strings(ds, dp->index, stringset,
+					     data + 4 * len);
+	} else if (stringset ==  ETH_SS_TEST) {
+		net_selftest_get_strings(data);
+	}
+
+}
+
+static void dsa_slave_get_ethtool_stats(struct net_device *dev,
+					struct ethtool_stats *stats,
+					uint64_t *data)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	struct pcpu_sw_netstats *s;
+	unsigned int start;
+	int i;
+
+	for_each_possible_cpu(i) {
+		u64 tx_packets, tx_bytes, rx_packets, rx_bytes;
+
+		s = per_cpu_ptr(dev->tstats, i);
+		do {
+			start = u64_stats_fetch_begin_irq(&s->syncp);
+			tx_packets = u64_stats_read(&s->tx_packets);
+			tx_bytes = u64_stats_read(&s->tx_bytes);
+			rx_packets = u64_stats_read(&s->rx_packets);
+			rx_bytes = u64_stats_read(&s->rx_bytes);
+		} while (u64_stats_fetch_retry_irq(&s->syncp, start));
+		data[0] += tx_packets;
+		data[1] += tx_bytes;
+		data[2] += rx_packets;
+		data[3] += rx_bytes;
+	}
+	if (ds->ops->get_ethtool_stats)
+		ds->ops->get_ethtool_stats(ds, dp->index, data + 4);
+}
+
+static int dsa_slave_get_sset_count(struct net_device *dev, int sset)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (sset == ETH_SS_STATS) {
+		int count = 0;
+
+		if (ds->ops->get_sset_count) {
+			count = ds->ops->get_sset_count(ds, dp->index, sset);
+			if (count < 0)
+				return count;
+		}
+
+		return count + 4;
+	} else if (sset ==  ETH_SS_TEST) {
+		return net_selftest_get_count();
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static void dsa_slave_get_eth_phy_stats(struct net_device *dev,
+					struct ethtool_eth_phy_stats *phy_stats)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_eth_phy_stats)
+		ds->ops->get_eth_phy_stats(ds, dp->index, phy_stats);
+}
+
+static void dsa_slave_get_eth_mac_stats(struct net_device *dev,
+					struct ethtool_eth_mac_stats *mac_stats)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_eth_mac_stats)
+		ds->ops->get_eth_mac_stats(ds, dp->index, mac_stats);
+}
+
+static void
+dsa_slave_get_eth_ctrl_stats(struct net_device *dev,
+			     struct ethtool_eth_ctrl_stats *ctrl_stats)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_eth_ctrl_stats)
+		ds->ops->get_eth_ctrl_stats(ds, dp->index, ctrl_stats);
+}
+
+static void
+dsa_slave_get_rmon_stats(struct net_device *dev,
+			 struct ethtool_rmon_stats *rmon_stats,
+			 const struct ethtool_rmon_hist_range **ranges)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_rmon_stats)
+		ds->ops->get_rmon_stats(ds, dp->index, rmon_stats, ranges);
+}
+
+static void dsa_slave_net_selftest(struct net_device *ndev,
+				   struct ethtool_test *etest, u64 *buf)
+{
+	struct dsa_port *dp = dsa_slave_to_port(ndev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->self_test) {
+		ds->ops->self_test(ds, dp->index, etest, buf);
+		return;
+	}
+
+	net_selftest(ndev, etest, buf);
+}
+
+static void dsa_slave_get_wol(struct net_device *dev, struct ethtool_wolinfo *w)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	phylink_ethtool_get_wol(dp->pl, w);
+
+	if (ds->ops->get_wol)
+		ds->ops->get_wol(ds, dp->index, w);
+}
+
+static int dsa_slave_set_wol(struct net_device *dev, struct ethtool_wolinfo *w)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	int ret = -EOPNOTSUPP;
+
+	phylink_ethtool_set_wol(dp->pl, w);
+
+	if (ds->ops->set_wol)
+		ret = ds->ops->set_wol(ds, dp->index, w);
+
+	return ret;
+}
+
+static int dsa_slave_set_eee(struct net_device *dev, struct ethtool_eee *e)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	int ret;
+
+	/* Port's PHY and MAC both need to be EEE capable */
+	if (!dev->phydev || !dp->pl)
+		return -ENODEV;
+
+	if (!ds->ops->set_mac_eee)
+		return -EOPNOTSUPP;
+
+	ret = ds->ops->set_mac_eee(ds, dp->index, e);
+	if (ret)
+		return ret;
+
+	return phylink_ethtool_set_eee(dp->pl, e);
+}
+
+static int dsa_slave_get_eee(struct net_device *dev, struct ethtool_eee *e)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	int ret;
+
+	/* Port's PHY and MAC both need to be EEE capable */
+	if (!dev->phydev || !dp->pl)
+		return -ENODEV;
+
+	if (!ds->ops->get_mac_eee)
+		return -EOPNOTSUPP;
+
+	ret = ds->ops->get_mac_eee(ds, dp->index, e);
+	if (ret)
+		return ret;
+
+	return phylink_ethtool_get_eee(dp->pl, e);
+}
+
+static int dsa_slave_get_link_ksettings(struct net_device *dev,
+					struct ethtool_link_ksettings *cmd)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return phylink_ethtool_ksettings_get(dp->pl, cmd);
+}
+
+static int dsa_slave_set_link_ksettings(struct net_device *dev,
+					const struct ethtool_link_ksettings *cmd)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return phylink_ethtool_ksettings_set(dp->pl, cmd);
+}
+
+static void dsa_slave_get_pause_stats(struct net_device *dev,
+				  struct ethtool_pause_stats *pause_stats)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_pause_stats)
+		ds->ops->get_pause_stats(ds, dp->index, pause_stats);
+}
+
+static void dsa_slave_get_pauseparam(struct net_device *dev,
+				     struct ethtool_pauseparam *pause)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	phylink_ethtool_get_pauseparam(dp->pl, pause);
+}
+
+static int dsa_slave_set_pauseparam(struct net_device *dev,
+				    struct ethtool_pauseparam *pause)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return phylink_ethtool_set_pauseparam(dp->pl, pause);
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static int dsa_slave_netpoll_setup(struct net_device *dev,
+				   struct netpoll_info *ni)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct netpoll *netpoll;
+	int err = 0;
+
+	netpoll = kzalloc(sizeof(*netpoll), GFP_KERNEL);
+	if (!netpoll)
+		return -ENOMEM;
+
+	err = __netpoll_setup(netpoll, master);
+	if (err) {
+		kfree(netpoll);
+		goto out;
+	}
+
+	p->netpoll = netpoll;
+out:
+	return err;
+}
+
+static void dsa_slave_netpoll_cleanup(struct net_device *dev)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct netpoll *netpoll = p->netpoll;
+
+	if (!netpoll)
+		return;
+
+	p->netpoll = NULL;
+
+	__netpoll_free(netpoll);
+}
+
+static void dsa_slave_poll_controller(struct net_device *dev)
+{
+}
+#endif
+
+static struct dsa_mall_tc_entry *
+dsa_slave_mall_tc_entry_find(struct net_device *dev, unsigned long cookie)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct dsa_mall_tc_entry *mall_tc_entry;
+
+	list_for_each_entry(mall_tc_entry, &p->mall_tc_list, list)
+		if (mall_tc_entry->cookie == cookie)
+			return mall_tc_entry;
+
+	return NULL;
+}
+
+static int
+dsa_slave_add_cls_matchall_mirred(struct net_device *dev,
+				  struct tc_cls_matchall_offload *cls,
+				  bool ingress)
+{
+	struct netlink_ext_ack *extack = cls->common.extack;
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct dsa_mall_mirror_tc_entry *mirror;
+	struct dsa_mall_tc_entry *mall_tc_entry;
+	struct dsa_switch *ds = dp->ds;
+	struct flow_action_entry *act;
+	struct dsa_port *to_dp;
+	int err;
+
+	if (!ds->ops->port_mirror_add)
+		return -EOPNOTSUPP;
+
+	if (!flow_action_basic_hw_stats_check(&cls->rule->action,
+					      cls->common.extack))
+		return -EOPNOTSUPP;
+
+	act = &cls->rule->action.entries[0];
+
+	if (!act->dev)
+		return -EINVAL;
+
+	if (!dsa_slave_dev_check(act->dev))
+		return -EOPNOTSUPP;
+
+	mall_tc_entry = kzalloc(sizeof(*mall_tc_entry), GFP_KERNEL);
+	if (!mall_tc_entry)
+		return -ENOMEM;
+
+	mall_tc_entry->cookie = cls->cookie;
+	mall_tc_entry->type = DSA_PORT_MALL_MIRROR;
+	mirror = &mall_tc_entry->mirror;
+
+	to_dp = dsa_slave_to_port(act->dev);
+
+	mirror->to_local_port = to_dp->index;
+	mirror->ingress = ingress;
+
+	err = ds->ops->port_mirror_add(ds, dp->index, mirror, ingress, extack);
+	if (err) {
+		kfree(mall_tc_entry);
+		return err;
+	}
+
+	list_add_tail(&mall_tc_entry->list, &p->mall_tc_list);
+
+	return err;
+}
+
+static int
+dsa_slave_add_cls_matchall_police(struct net_device *dev,
+				  struct tc_cls_matchall_offload *cls,
+				  bool ingress)
+{
+	struct netlink_ext_ack *extack = cls->common.extack;
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct dsa_mall_policer_tc_entry *policer;
+	struct dsa_mall_tc_entry *mall_tc_entry;
+	struct dsa_switch *ds = dp->ds;
+	struct flow_action_entry *act;
+	int err;
+
+	if (!ds->ops->port_policer_add) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Policing offload not implemented");
+		return -EOPNOTSUPP;
+	}
+
+	if (!ingress) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Only supported on ingress qdisc");
+		return -EOPNOTSUPP;
+	}
+
+	if (!flow_action_basic_hw_stats_check(&cls->rule->action,
+					      cls->common.extack))
+		return -EOPNOTSUPP;
+
+	list_for_each_entry(mall_tc_entry, &p->mall_tc_list, list) {
+		if (mall_tc_entry->type == DSA_PORT_MALL_POLICER) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "Only one port policer allowed");
+			return -EEXIST;
+		}
+	}
+
+	act = &cls->rule->action.entries[0];
+
+	mall_tc_entry = kzalloc(sizeof(*mall_tc_entry), GFP_KERNEL);
+	if (!mall_tc_entry)
+		return -ENOMEM;
+
+	mall_tc_entry->cookie = cls->cookie;
+	mall_tc_entry->type = DSA_PORT_MALL_POLICER;
+	policer = &mall_tc_entry->policer;
+	policer->rate_bytes_per_sec = act->police.rate_bytes_ps;
+	policer->burst = act->police.burst;
+
+	err = ds->ops->port_policer_add(ds, dp->index, policer);
+	if (err) {
+		kfree(mall_tc_entry);
+		return err;
+	}
+
+	list_add_tail(&mall_tc_entry->list, &p->mall_tc_list);
+
+	return err;
+}
+
+static int dsa_slave_add_cls_matchall(struct net_device *dev,
+				      struct tc_cls_matchall_offload *cls,
+				      bool ingress)
+{
+	int err = -EOPNOTSUPP;
+
+	if (cls->common.protocol == htons(ETH_P_ALL) &&
+	    flow_offload_has_one_action(&cls->rule->action) &&
+	    cls->rule->action.entries[0].id == FLOW_ACTION_MIRRED)
+		err = dsa_slave_add_cls_matchall_mirred(dev, cls, ingress);
+	else if (flow_offload_has_one_action(&cls->rule->action) &&
+		 cls->rule->action.entries[0].id == FLOW_ACTION_POLICE)
+		err = dsa_slave_add_cls_matchall_police(dev, cls, ingress);
+
+	return err;
+}
+
+static void dsa_slave_del_cls_matchall(struct net_device *dev,
+				       struct tc_cls_matchall_offload *cls)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_mall_tc_entry *mall_tc_entry;
+	struct dsa_switch *ds = dp->ds;
+
+	mall_tc_entry = dsa_slave_mall_tc_entry_find(dev, cls->cookie);
+	if (!mall_tc_entry)
+		return;
+
+	list_del(&mall_tc_entry->list);
+
+	switch (mall_tc_entry->type) {
+	case DSA_PORT_MALL_MIRROR:
+		if (ds->ops->port_mirror_del)
+			ds->ops->port_mirror_del(ds, dp->index,
+						 &mall_tc_entry->mirror);
+		break;
+	case DSA_PORT_MALL_POLICER:
+		if (ds->ops->port_policer_del)
+			ds->ops->port_policer_del(ds, dp->index);
+		break;
+	default:
+		WARN_ON(1);
+	}
+
+	kfree(mall_tc_entry);
+}
+
+static int dsa_slave_setup_tc_cls_matchall(struct net_device *dev,
+					   struct tc_cls_matchall_offload *cls,
+					   bool ingress)
+{
+	if (cls->common.chain_index)
+		return -EOPNOTSUPP;
+
+	switch (cls->command) {
+	case TC_CLSMATCHALL_REPLACE:
+		return dsa_slave_add_cls_matchall(dev, cls, ingress);
+	case TC_CLSMATCHALL_DESTROY:
+		dsa_slave_del_cls_matchall(dev, cls);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int dsa_slave_add_cls_flower(struct net_device *dev,
+				    struct flow_cls_offload *cls,
+				    bool ingress)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+
+	if (!ds->ops->cls_flower_add)
+		return -EOPNOTSUPP;
+
+	return ds->ops->cls_flower_add(ds, port, cls, ingress);
+}
+
+static int dsa_slave_del_cls_flower(struct net_device *dev,
+				    struct flow_cls_offload *cls,
+				    bool ingress)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+
+	if (!ds->ops->cls_flower_del)
+		return -EOPNOTSUPP;
+
+	return ds->ops->cls_flower_del(ds, port, cls, ingress);
+}
+
+static int dsa_slave_stats_cls_flower(struct net_device *dev,
+				      struct flow_cls_offload *cls,
+				      bool ingress)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+
+	if (!ds->ops->cls_flower_stats)
+		return -EOPNOTSUPP;
+
+	return ds->ops->cls_flower_stats(ds, port, cls, ingress);
+}
+
+static int dsa_slave_setup_tc_cls_flower(struct net_device *dev,
+					 struct flow_cls_offload *cls,
+					 bool ingress)
+{
+	switch (cls->command) {
+	case FLOW_CLS_REPLACE:
+		return dsa_slave_add_cls_flower(dev, cls, ingress);
+	case FLOW_CLS_DESTROY:
+		return dsa_slave_del_cls_flower(dev, cls, ingress);
+	case FLOW_CLS_STATS:
+		return dsa_slave_stats_cls_flower(dev, cls, ingress);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int dsa_slave_setup_tc_block_cb(enum tc_setup_type type, void *type_data,
+				       void *cb_priv, bool ingress)
+{
+	struct net_device *dev = cb_priv;
+
+	if (!tc_can_offload(dev))
+		return -EOPNOTSUPP;
+
+	switch (type) {
+	case TC_SETUP_CLSMATCHALL:
+		return dsa_slave_setup_tc_cls_matchall(dev, type_data, ingress);
+	case TC_SETUP_CLSFLOWER:
+		return dsa_slave_setup_tc_cls_flower(dev, type_data, ingress);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int dsa_slave_setup_tc_block_cb_ig(enum tc_setup_type type,
+					  void *type_data, void *cb_priv)
+{
+	return dsa_slave_setup_tc_block_cb(type, type_data, cb_priv, true);
+}
+
+static int dsa_slave_setup_tc_block_cb_eg(enum tc_setup_type type,
+					  void *type_data, void *cb_priv)
+{
+	return dsa_slave_setup_tc_block_cb(type, type_data, cb_priv, false);
+}
+
+static LIST_HEAD(dsa_slave_block_cb_list);
+
+static int dsa_slave_setup_tc_block(struct net_device *dev,
+				    struct flow_block_offload *f)
+{
+	struct flow_block_cb *block_cb;
+	flow_setup_cb_t *cb;
+
+	if (f->binder_type == FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS)
+		cb = dsa_slave_setup_tc_block_cb_ig;
+	else if (f->binder_type == FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
+		cb = dsa_slave_setup_tc_block_cb_eg;
+	else
+		return -EOPNOTSUPP;
+
+	f->driver_block_list = &dsa_slave_block_cb_list;
+
+	switch (f->command) {
+	case FLOW_BLOCK_BIND:
+		if (flow_block_cb_is_busy(cb, dev, &dsa_slave_block_cb_list))
+			return -EBUSY;
+
+		block_cb = flow_block_cb_alloc(cb, dev, dev, NULL);
+		if (IS_ERR(block_cb))
+			return PTR_ERR(block_cb);
+
+		flow_block_cb_add(block_cb, f);
+		list_add_tail(&block_cb->driver_list, &dsa_slave_block_cb_list);
+		return 0;
+	case FLOW_BLOCK_UNBIND:
+		block_cb = flow_block_cb_lookup(f->block, cb, dev);
+		if (!block_cb)
+			return -ENOENT;
+
+		flow_block_cb_remove(block_cb, f);
+		list_del(&block_cb->driver_list);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int dsa_slave_setup_ft_block(struct dsa_switch *ds, int port,
+				    void *type_data)
+{
+	struct net_device *master = dsa_port_to_master(dsa_to_port(ds, port));
+
+	if (!master->netdev_ops->ndo_setup_tc)
+		return -EOPNOTSUPP;
+
+	return master->netdev_ops->ndo_setup_tc(master, TC_SETUP_FT, type_data);
+}
+
+static int dsa_slave_setup_tc(struct net_device *dev, enum tc_setup_type type,
+			      void *type_data)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	switch (type) {
+	case TC_SETUP_BLOCK:
+		return dsa_slave_setup_tc_block(dev, type_data);
+	case TC_SETUP_FT:
+		return dsa_slave_setup_ft_block(ds, dp->index, type_data);
+	default:
+		break;
+	}
+
+	if (!ds->ops->port_setup_tc)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_setup_tc(ds, dp->index, type, type_data);
+}
+
+static int dsa_slave_get_rxnfc(struct net_device *dev,
+			       struct ethtool_rxnfc *nfc, u32 *rule_locs)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->get_rxnfc)
+		return -EOPNOTSUPP;
+
+	return ds->ops->get_rxnfc(ds, dp->index, nfc, rule_locs);
+}
+
+static int dsa_slave_set_rxnfc(struct net_device *dev,
+			       struct ethtool_rxnfc *nfc)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->set_rxnfc)
+		return -EOPNOTSUPP;
+
+	return ds->ops->set_rxnfc(ds, dp->index, nfc);
+}
+
+static int dsa_slave_get_ts_info(struct net_device *dev,
+				 struct ethtool_ts_info *ts)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct dsa_switch *ds = p->dp->ds;
+
+	if (!ds->ops->get_ts_info)
+		return -EOPNOTSUPP;
+
+	return ds->ops->get_ts_info(ds, p->dp->index, ts);
+}
+
+static int dsa_slave_vlan_rx_add_vid(struct net_device *dev, __be16 proto,
+				     u16 vid)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_vlan vlan = {
+		.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
+		.vid = vid,
+		/* This API only allows programming tagged, non-PVID VIDs */
+		.flags = 0,
+	};
+	struct netlink_ext_ack extack = {0};
+	int ret;
+
+	/* User port... */
+	ret = dsa_port_vlan_add(dp, &vlan, &extack);
+	if (ret) {
+		if (extack._msg)
+			netdev_err(dev, "%s\n", extack._msg);
+		return ret;
+	}
+
+	/* And CPU port... */
+	ret = dsa_port_host_vlan_add(dp, &vlan, &extack);
+	if (ret) {
+		if (extack._msg)
+			netdev_err(dev, "CPU port %d: %s\n", dp->cpu_dp->index,
+				   extack._msg);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int dsa_slave_vlan_rx_kill_vid(struct net_device *dev, __be16 proto,
+				      u16 vid)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_vlan vlan = {
+		.vid = vid,
+		/* This API only allows programming tagged, non-PVID VIDs */
+		.flags = 0,
+	};
+	int err;
+
+	err = dsa_port_vlan_del(dp, &vlan);
+	if (err)
+		return err;
+
+	return dsa_port_host_vlan_del(dp, &vlan);
+}
+
+static int dsa_slave_restore_vlan(struct net_device *vdev, int vid, void *arg)
+{
+	__be16 proto = vdev ? vlan_dev_vlan_proto(vdev) : htons(ETH_P_8021Q);
+
+	return dsa_slave_vlan_rx_add_vid(arg, proto, vid);
+}
+
+static int dsa_slave_clear_vlan(struct net_device *vdev, int vid, void *arg)
+{
+	__be16 proto = vdev ? vlan_dev_vlan_proto(vdev) : htons(ETH_P_8021Q);
+
+	return dsa_slave_vlan_rx_kill_vid(arg, proto, vid);
+}
+
+/* Keep the VLAN RX filtering list in sync with the hardware only if VLAN
+ * filtering is enabled. The baseline is that only ports that offload a
+ * VLAN-aware bridge are VLAN-aware, and standalone ports are VLAN-unaware,
+ * but there are exceptions for quirky hardware.
+ *
+ * If ds->vlan_filtering_is_global = true, then standalone ports which share
+ * the same switch with other ports that offload a VLAN-aware bridge are also
+ * inevitably VLAN-aware.
+ *
+ * To summarize, a DSA switch port offloads:
+ *
+ * - If standalone (this includes software bridge, software LAG):
+ *     - if ds->needs_standalone_vlan_filtering = true, OR if
+ *       (ds->vlan_filtering_is_global = true AND there are bridges spanning
+ *       this switch chip which have vlan_filtering=1)
+ *         - the 8021q upper VLANs
+ *     - else (standalone VLAN filtering is not needed, VLAN filtering is not
+ *       global, or it is, but no port is under a VLAN-aware bridge):
+ *         - no VLAN (any 8021q upper is a software VLAN)
+ *
+ * - If under a vlan_filtering=0 bridge which it offload:
+ *     - if ds->configure_vlan_while_not_filtering = true (default):
+ *         - the bridge VLANs. These VLANs are committed to hardware but inactive.
+ *     - else (deprecated):
+ *         - no VLAN. The bridge VLANs are not restored when VLAN awareness is
+ *           enabled, so this behavior is broken and discouraged.
+ *
+ * - If under a vlan_filtering=1 bridge which it offload:
+ *     - the bridge VLANs
+ *     - the 8021q upper VLANs
+ */
+int dsa_slave_manage_vlan_filtering(struct net_device *slave,
+				    bool vlan_filtering)
+{
+	int err;
+
+	if (vlan_filtering) {
+		slave->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
+
+		err = vlan_for_each(slave, dsa_slave_restore_vlan, slave);
+		if (err) {
+			vlan_for_each(slave, dsa_slave_clear_vlan, slave);
+			slave->features &= ~NETIF_F_HW_VLAN_CTAG_FILTER;
+			return err;
+		}
+	} else {
+		err = vlan_for_each(slave, dsa_slave_clear_vlan, slave);
+		if (err)
+			return err;
+
+		slave->features &= ~NETIF_F_HW_VLAN_CTAG_FILTER;
+	}
+
+	return 0;
+}
+
+struct dsa_hw_port {
+	struct list_head list;
+	struct net_device *dev;
+	int old_mtu;
+};
+
+static int dsa_hw_port_list_set_mtu(struct list_head *hw_port_list, int mtu)
+{
+	const struct dsa_hw_port *p;
+	int err;
+
+	list_for_each_entry(p, hw_port_list, list) {
+		if (p->dev->mtu == mtu)
+			continue;
+
+		err = dev_set_mtu(p->dev, mtu);
+		if (err)
+			goto rollback;
+	}
+
+	return 0;
+
+rollback:
+	list_for_each_entry_continue_reverse(p, hw_port_list, list) {
+		if (p->dev->mtu == p->old_mtu)
+			continue;
+
+		if (dev_set_mtu(p->dev, p->old_mtu))
+			netdev_err(p->dev, "Failed to restore MTU\n");
+	}
+
+	return err;
+}
+
+static void dsa_hw_port_list_free(struct list_head *hw_port_list)
+{
+	struct dsa_hw_port *p, *n;
+
+	list_for_each_entry_safe(p, n, hw_port_list, list)
+		kfree(p);
+}
+
+/* Make the hardware datapath to/from @dev limited to a common MTU */
+static void dsa_bridge_mtu_normalization(struct dsa_port *dp)
+{
+	struct list_head hw_port_list;
+	struct dsa_switch_tree *dst;
+	int min_mtu = ETH_MAX_MTU;
+	struct dsa_port *other_dp;
+	int err;
+
+	if (!dp->ds->mtu_enforcement_ingress)
+		return;
+
+	if (!dp->bridge)
+		return;
+
+	INIT_LIST_HEAD(&hw_port_list);
+
+	/* Populate the list of ports that are part of the same bridge
+	 * as the newly added/modified port
+	 */
+	list_for_each_entry(dst, &dsa_tree_list, list) {
+		list_for_each_entry(other_dp, &dst->ports, list) {
+			struct dsa_hw_port *hw_port;
+			struct net_device *slave;
+
+			if (other_dp->type != DSA_PORT_TYPE_USER)
+				continue;
+
+			if (!dsa_port_bridge_same(dp, other_dp))
+				continue;
+
+			if (!other_dp->ds->mtu_enforcement_ingress)
+				continue;
+
+			slave = other_dp->slave;
+
+			if (min_mtu > slave->mtu)
+				min_mtu = slave->mtu;
+
+			hw_port = kzalloc(sizeof(*hw_port), GFP_KERNEL);
+			if (!hw_port)
+				goto out;
+
+			hw_port->dev = slave;
+			hw_port->old_mtu = slave->mtu;
+
+			list_add(&hw_port->list, &hw_port_list);
+		}
+	}
+
+	/* Attempt to configure the entire hardware bridge to the newly added
+	 * interface's MTU first, regardless of whether the intention of the
+	 * user was to raise or lower it.
+	 */
+	err = dsa_hw_port_list_set_mtu(&hw_port_list, dp->slave->mtu);
+	if (!err)
+		goto out;
+
+	/* Clearly that didn't work out so well, so just set the minimum MTU on
+	 * all hardware bridge ports now. If this fails too, then all ports will
+	 * still have their old MTU rolled back anyway.
+	 */
+	dsa_hw_port_list_set_mtu(&hw_port_list, min_mtu);
+
+out:
+	dsa_hw_port_list_free(&hw_port_list);
+}
+
+int dsa_slave_change_mtu(struct net_device *dev, int new_mtu)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_port *cpu_dp = dp->cpu_dp;
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_port *other_dp;
+	int largest_mtu = 0;
+	int new_master_mtu;
+	int old_master_mtu;
+	int mtu_limit;
+	int overhead;
+	int cpu_mtu;
+	int err;
+
+	if (!ds->ops->port_change_mtu)
+		return -EOPNOTSUPP;
+
+	dsa_tree_for_each_user_port(other_dp, ds->dst) {
+		int slave_mtu;
+
+		/* During probe, this function will be called for each slave
+		 * device, while not all of them have been allocated. That's
+		 * ok, it doesn't change what the maximum is, so ignore it.
+		 */
+		if (!other_dp->slave)
+			continue;
+
+		/* Pretend that we already applied the setting, which we
+		 * actually haven't (still haven't done all integrity checks)
+		 */
+		if (dp == other_dp)
+			slave_mtu = new_mtu;
+		else
+			slave_mtu = other_dp->slave->mtu;
+
+		if (largest_mtu < slave_mtu)
+			largest_mtu = slave_mtu;
+	}
+
+	overhead = dsa_tag_protocol_overhead(cpu_dp->tag_ops);
+	mtu_limit = min_t(int, master->max_mtu, dev->max_mtu + overhead);
+	old_master_mtu = master->mtu;
+	new_master_mtu = largest_mtu + overhead;
+	if (new_master_mtu > mtu_limit)
+		return -ERANGE;
+
+	/* If the master MTU isn't over limit, there's no need to check the CPU
+	 * MTU, since that surely isn't either.
+	 */
+	cpu_mtu = largest_mtu;
+
+	/* Start applying stuff */
+	if (new_master_mtu != old_master_mtu) {
+		err = dev_set_mtu(master, new_master_mtu);
+		if (err < 0)
+			goto out_master_failed;
+
+		/* We only need to propagate the MTU of the CPU port to
+		 * upstream switches, so emit a notifier which updates them.
+		 */
+		err = dsa_port_mtu_change(cpu_dp, cpu_mtu);
+		if (err)
+			goto out_cpu_failed;
+	}
+
+	err = ds->ops->port_change_mtu(ds, dp->index, new_mtu);
+	if (err)
+		goto out_port_failed;
+
+	dev->mtu = new_mtu;
+
+	dsa_bridge_mtu_normalization(dp);
+
+	return 0;
+
+out_port_failed:
+	if (new_master_mtu != old_master_mtu)
+		dsa_port_mtu_change(cpu_dp, old_master_mtu - overhead);
+out_cpu_failed:
+	if (new_master_mtu != old_master_mtu)
+		dev_set_mtu(master, old_master_mtu);
+out_master_failed:
+	return err;
+}
+
+static int __maybe_unused
+dsa_slave_dcbnl_set_default_prio(struct net_device *dev, struct dcb_app *app)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	unsigned long mask, new_prio;
+	int err, port = dp->index;
+
+	if (!ds->ops->port_set_default_prio)
+		return -EOPNOTSUPP;
+
+	err = dcb_ieee_setapp(dev, app);
+	if (err)
+		return err;
+
+	mask = dcb_ieee_getapp_mask(dev, app);
+	new_prio = __fls(mask);
+
+	err = ds->ops->port_set_default_prio(ds, port, new_prio);
+	if (err) {
+		dcb_ieee_delapp(dev, app);
+		return err;
+	}
+
+	return 0;
+}
+
+static int __maybe_unused
+dsa_slave_dcbnl_add_dscp_prio(struct net_device *dev, struct dcb_app *app)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	unsigned long mask, new_prio;
+	int err, port = dp->index;
+	u8 dscp = app->protocol;
+
+	if (!ds->ops->port_add_dscp_prio)
+		return -EOPNOTSUPP;
+
+	if (dscp >= 64) {
+		netdev_err(dev, "DSCP APP entry with protocol value %u is invalid\n",
+			   dscp);
+		return -EINVAL;
+	}
+
+	err = dcb_ieee_setapp(dev, app);
+	if (err)
+		return err;
+
+	mask = dcb_ieee_getapp_mask(dev, app);
+	new_prio = __fls(mask);
+
+	err = ds->ops->port_add_dscp_prio(ds, port, dscp, new_prio);
+	if (err) {
+		dcb_ieee_delapp(dev, app);
+		return err;
+	}
+
+	return 0;
+}
+
+static int __maybe_unused dsa_slave_dcbnl_ieee_setapp(struct net_device *dev,
+						      struct dcb_app *app)
+{
+	switch (app->selector) {
+	case IEEE_8021QAZ_APP_SEL_ETHERTYPE:
+		switch (app->protocol) {
+		case 0:
+			return dsa_slave_dcbnl_set_default_prio(dev, app);
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	case IEEE_8021QAZ_APP_SEL_DSCP:
+		return dsa_slave_dcbnl_add_dscp_prio(dev, app);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int __maybe_unused
+dsa_slave_dcbnl_del_default_prio(struct net_device *dev, struct dcb_app *app)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	unsigned long mask, new_prio;
+	int err, port = dp->index;
+
+	if (!ds->ops->port_set_default_prio)
+		return -EOPNOTSUPP;
+
+	err = dcb_ieee_delapp(dev, app);
+	if (err)
+		return err;
+
+	mask = dcb_ieee_getapp_mask(dev, app);
+	new_prio = mask ? __fls(mask) : 0;
+
+	err = ds->ops->port_set_default_prio(ds, port, new_prio);
+	if (err) {
+		dcb_ieee_setapp(dev, app);
+		return err;
+	}
+
+	return 0;
+}
+
+static int __maybe_unused
+dsa_slave_dcbnl_del_dscp_prio(struct net_device *dev, struct dcb_app *app)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	int err, port = dp->index;
+	u8 dscp = app->protocol;
+
+	if (!ds->ops->port_del_dscp_prio)
+		return -EOPNOTSUPP;
+
+	err = dcb_ieee_delapp(dev, app);
+	if (err)
+		return err;
+
+	err = ds->ops->port_del_dscp_prio(ds, port, dscp, app->priority);
+	if (err) {
+		dcb_ieee_setapp(dev, app);
+		return err;
+	}
+
+	return 0;
+}
+
+static int __maybe_unused dsa_slave_dcbnl_ieee_delapp(struct net_device *dev,
+						      struct dcb_app *app)
+{
+	switch (app->selector) {
+	case IEEE_8021QAZ_APP_SEL_ETHERTYPE:
+		switch (app->protocol) {
+		case 0:
+			return dsa_slave_dcbnl_del_default_prio(dev, app);
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	case IEEE_8021QAZ_APP_SEL_DSCP:
+		return dsa_slave_dcbnl_del_dscp_prio(dev, app);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+/* Pre-populate the DCB application priority table with the priorities
+ * configured during switch setup, which we read from hardware here.
+ */
+static int dsa_slave_dcbnl_init(struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+	int err;
+
+	if (ds->ops->port_get_default_prio) {
+		int prio = ds->ops->port_get_default_prio(ds, port);
+		struct dcb_app app = {
+			.selector = IEEE_8021QAZ_APP_SEL_ETHERTYPE,
+			.protocol = 0,
+			.priority = prio,
+		};
+
+		if (prio < 0)
+			return prio;
+
+		err = dcb_ieee_setapp(dev, &app);
+		if (err)
+			return err;
+	}
+
+	if (ds->ops->port_get_dscp_prio) {
+		int protocol;
+
+		for (protocol = 0; protocol < 64; protocol++) {
+			struct dcb_app app = {
+				.selector = IEEE_8021QAZ_APP_SEL_DSCP,
+				.protocol = protocol,
+			};
+			int prio;
+
+			prio = ds->ops->port_get_dscp_prio(ds, port, protocol);
+			if (prio == -EOPNOTSUPP)
+				continue;
+			if (prio < 0)
+				return prio;
+
+			app.priority = prio;
+
+			err = dcb_ieee_setapp(dev, &app);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static const struct ethtool_ops dsa_slave_ethtool_ops = {
+	.get_drvinfo		= dsa_slave_get_drvinfo,
+	.get_regs_len		= dsa_slave_get_regs_len,
+	.get_regs		= dsa_slave_get_regs,
+	.nway_reset		= dsa_slave_nway_reset,
+	.get_link		= ethtool_op_get_link,
+	.get_eeprom_len		= dsa_slave_get_eeprom_len,
+	.get_eeprom		= dsa_slave_get_eeprom,
+	.set_eeprom		= dsa_slave_set_eeprom,
+	.get_strings		= dsa_slave_get_strings,
+	.get_ethtool_stats	= dsa_slave_get_ethtool_stats,
+	.get_sset_count		= dsa_slave_get_sset_count,
+	.get_eth_phy_stats	= dsa_slave_get_eth_phy_stats,
+	.get_eth_mac_stats	= dsa_slave_get_eth_mac_stats,
+	.get_eth_ctrl_stats	= dsa_slave_get_eth_ctrl_stats,
+	.get_rmon_stats		= dsa_slave_get_rmon_stats,
+	.set_wol		= dsa_slave_set_wol,
+	.get_wol		= dsa_slave_get_wol,
+	.set_eee		= dsa_slave_set_eee,
+	.get_eee		= dsa_slave_get_eee,
+	.get_link_ksettings	= dsa_slave_get_link_ksettings,
+	.set_link_ksettings	= dsa_slave_set_link_ksettings,
+	.get_pause_stats	= dsa_slave_get_pause_stats,
+	.get_pauseparam		= dsa_slave_get_pauseparam,
+	.set_pauseparam		= dsa_slave_set_pauseparam,
+	.get_rxnfc		= dsa_slave_get_rxnfc,
+	.set_rxnfc		= dsa_slave_set_rxnfc,
+	.get_ts_info		= dsa_slave_get_ts_info,
+	.self_test		= dsa_slave_net_selftest,
+};
+
+static const struct dcbnl_rtnl_ops __maybe_unused dsa_slave_dcbnl_ops = {
+	.ieee_setapp		= dsa_slave_dcbnl_ieee_setapp,
+	.ieee_delapp		= dsa_slave_dcbnl_ieee_delapp,
+};
+
+static struct devlink_port *dsa_slave_get_devlink_port(struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return &dp->devlink_port;
+}
+
+static void dsa_slave_get_stats64(struct net_device *dev,
+				  struct rtnl_link_stats64 *s)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->get_stats64)
+		ds->ops->get_stats64(ds, dp->index, s);
+	else
+		dev_get_tstats64(dev, s);
+}
+
+static int dsa_slave_fill_forward_path(struct net_device_path_ctx *ctx,
+				       struct net_device_path *path)
+{
+	struct dsa_port *dp = dsa_slave_to_port(ctx->dev);
+	struct net_device *master = dsa_port_to_master(dp);
+	struct dsa_port *cpu_dp = dp->cpu_dp;
+
+	path->dev = ctx->dev;
+	path->type = DEV_PATH_DSA;
+	path->dsa.proto = cpu_dp->tag_ops->proto;
+	path->dsa.port = dp->index;
+	ctx->dev = master;
+
+	return 0;
+}
+
+static const struct net_device_ops dsa_slave_netdev_ops = {
+	.ndo_open	 	= dsa_slave_open,
+	.ndo_stop		= dsa_slave_close,
+	.ndo_start_xmit		= dsa_slave_xmit,
+	.ndo_change_rx_flags	= dsa_slave_change_rx_flags,
+	.ndo_set_rx_mode	= dsa_slave_set_rx_mode,
+	.ndo_set_mac_address	= dsa_slave_set_mac_address,
+	.ndo_fdb_dump		= dsa_slave_fdb_dump,
+	.ndo_eth_ioctl		= dsa_slave_ioctl,
+	.ndo_get_iflink		= dsa_slave_get_iflink,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_netpoll_setup	= dsa_slave_netpoll_setup,
+	.ndo_netpoll_cleanup	= dsa_slave_netpoll_cleanup,
+	.ndo_poll_controller	= dsa_slave_poll_controller,
+#endif
+	.ndo_setup_tc		= dsa_slave_setup_tc,
+	.ndo_get_stats64	= dsa_slave_get_stats64,
+	.ndo_vlan_rx_add_vid	= dsa_slave_vlan_rx_add_vid,
+	.ndo_vlan_rx_kill_vid	= dsa_slave_vlan_rx_kill_vid,
+	.ndo_get_devlink_port	= dsa_slave_get_devlink_port,
+	.ndo_change_mtu		= dsa_slave_change_mtu,
+	.ndo_fill_forward_path	= dsa_slave_fill_forward_path,
+};
+
+static struct device_type dsa_type = {
+	.name	= "dsa",
+};
+
+void dsa_port_phylink_mac_change(struct dsa_switch *ds, int port, bool up)
+{
+	const struct dsa_port *dp = dsa_to_port(ds, port);
+
+	if (dp->pl)
+		phylink_mac_change(dp->pl, up);
+}
+EXPORT_SYMBOL_GPL(dsa_port_phylink_mac_change);
+
+static void dsa_slave_phylink_fixed_state(struct phylink_config *config,
+					  struct phylink_link_state *state)
+{
+	struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
+	struct dsa_switch *ds = dp->ds;
+
+	/* No need to check that this operation is valid, the callback would
+	 * not be called if it was not.
+	 */
+	ds->ops->phylink_fixed_state(ds, dp->index, state);
+}
+
+/* slave device setup *******************************************************/
+static int dsa_slave_phy_connect(struct net_device *slave_dev, int addr,
+				 u32 flags)
+{
+	struct dsa_port *dp = dsa_slave_to_port(slave_dev);
+	struct dsa_switch *ds = dp->ds;
+
+	slave_dev->phydev = mdiobus_get_phy(ds->slave_mii_bus, addr);
+	if (!slave_dev->phydev) {
+		netdev_err(slave_dev, "no phy at %d\n", addr);
+		return -ENODEV;
+	}
+
+	slave_dev->phydev->dev_flags |= flags;
+
+	return phylink_connect_phy(dp->pl, slave_dev->phydev);
+}
+
+static int dsa_slave_phy_setup(struct net_device *slave_dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(slave_dev);
+	struct device_node *port_dn = dp->dn;
+	struct dsa_switch *ds = dp->ds;
+	u32 phy_flags = 0;
+	int ret;
+
+	dp->pl_config.dev = &slave_dev->dev;
+	dp->pl_config.type = PHYLINK_NETDEV;
+
+	/* The get_fixed_state callback takes precedence over polling the
+	 * link GPIO in PHYLINK (see phylink_get_fixed_state).  Only set
+	 * this if the switch provides such a callback.
+	 */
+	if (ds->ops->phylink_fixed_state) {
+		dp->pl_config.get_fixed_state = dsa_slave_phylink_fixed_state;
+		dp->pl_config.poll_fixed_state = true;
+	}
+
+	ret = dsa_port_phylink_create(dp);
+	if (ret)
+		return ret;
+
+	if (ds->ops->get_phy_flags)
+		phy_flags = ds->ops->get_phy_flags(ds, dp->index);
+
+	ret = phylink_of_phy_connect(dp->pl, port_dn, phy_flags);
+	if (ret == -ENODEV && ds->slave_mii_bus) {
+		/* We could not connect to a designated PHY or SFP, so try to
+		 * use the switch internal MDIO bus instead
+		 */
+		ret = dsa_slave_phy_connect(slave_dev, dp->index, phy_flags);
+	}
+	if (ret) {
+		netdev_err(slave_dev, "failed to connect to PHY: %pe\n",
+			   ERR_PTR(ret));
+		dsa_port_phylink_destroy(dp);
+	}
+
+	return ret;
+}
+
+void dsa_slave_setup_tagger(struct net_device *slave)
+{
+	struct dsa_port *dp = dsa_slave_to_port(slave);
+	struct net_device *master = dsa_port_to_master(dp);
+	struct dsa_slave_priv *p = netdev_priv(slave);
+	const struct dsa_port *cpu_dp = dp->cpu_dp;
+	const struct dsa_switch *ds = dp->ds;
+
+	slave->needed_headroom = cpu_dp->tag_ops->needed_headroom;
+	slave->needed_tailroom = cpu_dp->tag_ops->needed_tailroom;
+	/* Try to save one extra realloc later in the TX path (in the master)
+	 * by also inheriting the master's needed headroom and tailroom.
+	 * The 8021q driver also does this.
+	 */
+	slave->needed_headroom += master->needed_headroom;
+	slave->needed_tailroom += master->needed_tailroom;
+
+	p->xmit = cpu_dp->tag_ops->xmit;
+
+	slave->features = master->vlan_features | NETIF_F_HW_TC;
+	slave->hw_features |= NETIF_F_HW_TC;
+	slave->features |= NETIF_F_LLTX;
+	if (slave->needed_tailroom)
+		slave->features &= ~(NETIF_F_SG | NETIF_F_FRAGLIST);
+	if (ds->needs_standalone_vlan_filtering)
+		slave->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
+}
+
+int dsa_slave_suspend(struct net_device *slave_dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(slave_dev);
+
+	if (!netif_running(slave_dev))
+		return 0;
+
+	netif_device_detach(slave_dev);
+
+	rtnl_lock();
+	phylink_stop(dp->pl);
+	rtnl_unlock();
+
+	return 0;
+}
+
+int dsa_slave_resume(struct net_device *slave_dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(slave_dev);
+
+	if (!netif_running(slave_dev))
+		return 0;
+
+	netif_device_attach(slave_dev);
+
+	rtnl_lock();
+	phylink_start(dp->pl);
+	rtnl_unlock();
+
+	return 0;
+}
+
+int dsa_slave_create(struct dsa_port *port)
+{
+	struct net_device *master = dsa_port_to_master(port);
+	struct dsa_switch *ds = port->ds;
+	const char *name = port->name;
+	struct net_device *slave_dev;
+	struct dsa_slave_priv *p;
+	int ret;
+
+	if (!ds->num_tx_queues)
+		ds->num_tx_queues = 1;
+
+	slave_dev = alloc_netdev_mqs(sizeof(struct dsa_slave_priv), name,
+				     NET_NAME_UNKNOWN, ether_setup,
+				     ds->num_tx_queues, 1);
+	if (slave_dev == NULL)
+		return -ENOMEM;
+
+	slave_dev->rtnl_link_ops = &dsa_link_ops;
+	slave_dev->ethtool_ops = &dsa_slave_ethtool_ops;
+#if IS_ENABLED(CONFIG_DCB)
+	slave_dev->dcbnl_ops = &dsa_slave_dcbnl_ops;
+#endif
+	if (!is_zero_ether_addr(port->mac))
+		eth_hw_addr_set(slave_dev, port->mac);
+	else
+		eth_hw_addr_inherit(slave_dev, master);
+	slave_dev->priv_flags |= IFF_NO_QUEUE;
+	if (dsa_switch_supports_uc_filtering(ds))
+		slave_dev->priv_flags |= IFF_UNICAST_FLT;
+	slave_dev->netdev_ops = &dsa_slave_netdev_ops;
+	if (ds->ops->port_max_mtu)
+		slave_dev->max_mtu = ds->ops->port_max_mtu(ds, port->index);
+	SET_NETDEV_DEVTYPE(slave_dev, &dsa_type);
+
+	SET_NETDEV_DEV(slave_dev, port->ds->dev);
+	slave_dev->dev.of_node = port->dn;
+	slave_dev->vlan_features = master->vlan_features;
+
+	p = netdev_priv(slave_dev);
+	slave_dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
+	if (!slave_dev->tstats) {
+		free_netdev(slave_dev);
+		return -ENOMEM;
+	}
+
+	ret = gro_cells_init(&p->gcells, slave_dev);
+	if (ret)
+		goto out_free;
+
+	p->dp = port;
+	INIT_LIST_HEAD(&p->mall_tc_list);
+	port->slave = slave_dev;
+	dsa_slave_setup_tagger(slave_dev);
+
+	netif_carrier_off(slave_dev);
+
+	ret = dsa_slave_phy_setup(slave_dev);
+	if (ret) {
+		netdev_err(slave_dev,
+			   "error %d setting up PHY for tree %d, switch %d, port %d\n",
+			   ret, ds->dst->index, ds->index, port->index);
+		goto out_gcells;
+	}
+
+	rtnl_lock();
+
+	ret = dsa_slave_change_mtu(slave_dev, ETH_DATA_LEN);
+	if (ret && ret != -EOPNOTSUPP)
+		dev_warn(ds->dev, "nonfatal error %d setting MTU to %d on port %d\n",
+			 ret, ETH_DATA_LEN, port->index);
+
+	ret = register_netdevice(slave_dev);
+	if (ret) {
+		netdev_err(master, "error %d registering interface %s\n",
+			   ret, slave_dev->name);
+		rtnl_unlock();
+		goto out_phy;
+	}
+
+	if (IS_ENABLED(CONFIG_DCB)) {
+		ret = dsa_slave_dcbnl_init(slave_dev);
+		if (ret) {
+			netdev_err(slave_dev,
+				   "failed to initialize DCB: %pe\n",
+				   ERR_PTR(ret));
+			rtnl_unlock();
+			goto out_unregister;
+		}
+	}
+
+	ret = netdev_upper_dev_link(master, slave_dev, NULL);
+
+	rtnl_unlock();
+
+	if (ret)
+		goto out_unregister;
+
+	return 0;
+
+out_unregister:
+	unregister_netdev(slave_dev);
+out_phy:
+	rtnl_lock();
+	phylink_disconnect_phy(p->dp->pl);
+	rtnl_unlock();
+	dsa_port_phylink_destroy(p->dp);
+out_gcells:
+	gro_cells_destroy(&p->gcells);
+out_free:
+	free_percpu(slave_dev->tstats);
+	free_netdev(slave_dev);
+	port->slave = NULL;
+	return ret;
+}
+
+void dsa_slave_destroy(struct net_device *slave_dev)
+{
+	struct net_device *master = dsa_slave_to_master(slave_dev);
+	struct dsa_port *dp = dsa_slave_to_port(slave_dev);
+	struct dsa_slave_priv *p = netdev_priv(slave_dev);
+
+	netif_carrier_off(slave_dev);
+	rtnl_lock();
+	netdev_upper_dev_unlink(master, slave_dev);
+	unregister_netdevice(slave_dev);
+	phylink_disconnect_phy(dp->pl);
+	rtnl_unlock();
+
+	dsa_port_phylink_destroy(dp);
+	gro_cells_destroy(&p->gcells);
+	free_percpu(slave_dev->tstats);
+	free_netdev(slave_dev);
+}
+
+int dsa_slave_change_master(struct net_device *dev, struct net_device *master,
+			    struct netlink_ext_ack *extack)
+{
+	struct net_device *old_master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	struct net_device *upper;
+	struct list_head *iter;
+	int err;
+
+	if (master == old_master)
+		return 0;
+
+	if (!ds->ops->port_change_master) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Driver does not support changing DSA master");
+		return -EOPNOTSUPP;
+	}
+
+	if (!netdev_uses_dsa(master)) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Interface not eligible as DSA master");
+		return -EOPNOTSUPP;
+	}
+
+	netdev_for_each_upper_dev_rcu(master, upper, iter) {
+		if (dsa_slave_dev_check(upper))
+			continue;
+		if (netif_is_bridge_master(upper))
+			continue;
+		NL_SET_ERR_MSG_MOD(extack, "Cannot join master with unknown uppers");
+		return -EOPNOTSUPP;
+	}
+
+	/* Since we allow live-changing the DSA master, plus we auto-open the
+	 * DSA master when the user port opens => we need to ensure that the
+	 * new DSA master is open too.
+	 */
+	if (dev->flags & IFF_UP) {
+		err = dev_open(master, extack);
+		if (err)
+			return err;
+	}
+
+	netdev_upper_dev_unlink(old_master, dev);
+
+	err = netdev_upper_dev_link(master, dev, extack);
+	if (err)
+		goto out_revert_old_master_unlink;
+
+	err = dsa_port_change_master(dp, master, extack);
+	if (err)
+		goto out_revert_master_link;
+
+	/* Update the MTU of the new CPU port through cross-chip notifiers */
+	err = dsa_slave_change_mtu(dev, dev->mtu);
+	if (err && err != -EOPNOTSUPP) {
+		netdev_warn(dev,
+			    "nonfatal error updating MTU with new master: %pe\n",
+			    ERR_PTR(err));
+	}
+
+	/* If the port doesn't have its own MAC address and relies on the DSA
+	 * master's one, inherit it again from the new DSA master.
+	 */
+	if (is_zero_ether_addr(dp->mac))
+		eth_hw_addr_inherit(dev, master);
+
+	return 0;
+
+out_revert_master_link:
+	netdev_upper_dev_unlink(master, dev);
+out_revert_old_master_unlink:
+	netdev_upper_dev_link(old_master, dev, NULL);
+	return err;
+}
+
+bool dsa_slave_dev_check(const struct net_device *dev)
+{
+	return dev->netdev_ops == &dsa_slave_netdev_ops;
+}
+EXPORT_SYMBOL_GPL(dsa_slave_dev_check);
+
+static int dsa_slave_changeupper(struct net_device *dev,
+				 struct netdev_notifier_changeupper_info *info)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct netlink_ext_ack *extack;
+	int err = NOTIFY_DONE;
+
+	if (!dsa_slave_dev_check(dev))
+		return err;
+
+	extack = netdev_notifier_info_to_extack(&info->info);
+
+	if (netif_is_bridge_master(info->upper_dev)) {
+		if (info->linking) {
+			err = dsa_port_bridge_join(dp, info->upper_dev, extack);
+			if (!err)
+				dsa_bridge_mtu_normalization(dp);
+			if (err == -EOPNOTSUPP) {
+				if (extack && !extack->_msg)
+					NL_SET_ERR_MSG_MOD(extack,
+							   "Offloading not supported");
+				err = 0;
+			}
+			err = notifier_from_errno(err);
+		} else {
+			dsa_port_bridge_leave(dp, info->upper_dev);
+			err = NOTIFY_OK;
+		}
+	} else if (netif_is_lag_master(info->upper_dev)) {
+		if (info->linking) {
+			err = dsa_port_lag_join(dp, info->upper_dev,
+						info->upper_info, extack);
+			if (err == -EOPNOTSUPP) {
+				NL_SET_ERR_MSG_MOD(info->info.extack,
+						   "Offloading not supported");
+				err = 0;
+			}
+			err = notifier_from_errno(err);
+		} else {
+			dsa_port_lag_leave(dp, info->upper_dev);
+			err = NOTIFY_OK;
+		}
+	} else if (is_hsr_master(info->upper_dev)) {
+		if (info->linking) {
+			err = dsa_port_hsr_join(dp, info->upper_dev);
+			if (err == -EOPNOTSUPP) {
+				NL_SET_ERR_MSG_MOD(info->info.extack,
+						   "Offloading not supported");
+				err = 0;
+			}
+			err = notifier_from_errno(err);
+		} else {
+			dsa_port_hsr_leave(dp, info->upper_dev);
+			err = NOTIFY_OK;
+		}
+	}
+
+	return err;
+}
+
+static int dsa_slave_prechangeupper(struct net_device *dev,
+				    struct netdev_notifier_changeupper_info *info)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	if (!dsa_slave_dev_check(dev))
+		return NOTIFY_DONE;
+
+	if (netif_is_bridge_master(info->upper_dev) && !info->linking)
+		dsa_port_pre_bridge_leave(dp, info->upper_dev);
+	else if (netif_is_lag_master(info->upper_dev) && !info->linking)
+		dsa_port_pre_lag_leave(dp, info->upper_dev);
+	/* dsa_port_pre_hsr_leave is not yet necessary since hsr cannot be
+	 * meaningfully enslaved to a bridge yet
+	 */
+
+	return NOTIFY_DONE;
+}
+
+static int
+dsa_slave_lag_changeupper(struct net_device *dev,
+			  struct netdev_notifier_changeupper_info *info)
+{
+	struct net_device *lower;
+	struct list_head *iter;
+	int err = NOTIFY_DONE;
+	struct dsa_port *dp;
+
+	if (!netif_is_lag_master(dev))
+		return err;
+
+	netdev_for_each_lower_dev(dev, lower, iter) {
+		if (!dsa_slave_dev_check(lower))
+			continue;
+
+		dp = dsa_slave_to_port(lower);
+		if (!dp->lag)
+			/* Software LAG */
+			continue;
+
+		err = dsa_slave_changeupper(lower, info);
+		if (notifier_to_errno(err))
+			break;
+	}
+
+	return err;
+}
+
+/* Same as dsa_slave_lag_changeupper() except that it calls
+ * dsa_slave_prechangeupper()
+ */
+static int
+dsa_slave_lag_prechangeupper(struct net_device *dev,
+			     struct netdev_notifier_changeupper_info *info)
+{
+	struct net_device *lower;
+	struct list_head *iter;
+	int err = NOTIFY_DONE;
+	struct dsa_port *dp;
+
+	if (!netif_is_lag_master(dev))
+		return err;
+
+	netdev_for_each_lower_dev(dev, lower, iter) {
+		if (!dsa_slave_dev_check(lower))
+			continue;
+
+		dp = dsa_slave_to_port(lower);
+		if (!dp->lag)
+			/* Software LAG */
+			continue;
+
+		err = dsa_slave_prechangeupper(lower, info);
+		if (notifier_to_errno(err))
+			break;
+	}
+
+	return err;
+}
+
+static int
+dsa_prevent_bridging_8021q_upper(struct net_device *dev,
+				 struct netdev_notifier_changeupper_info *info)
+{
+	struct netlink_ext_ack *ext_ack;
+	struct net_device *slave, *br;
+	struct dsa_port *dp;
+
+	ext_ack = netdev_notifier_info_to_extack(&info->info);
+
+	if (!is_vlan_dev(dev))
+		return NOTIFY_DONE;
+
+	slave = vlan_dev_real_dev(dev);
+	if (!dsa_slave_dev_check(slave))
+		return NOTIFY_DONE;
+
+	dp = dsa_slave_to_port(slave);
+	br = dsa_port_bridge_dev_get(dp);
+	if (!br)
+		return NOTIFY_DONE;
+
+	/* Deny enslaving a VLAN device into a VLAN-aware bridge */
+	if (br_vlan_enabled(br) &&
+	    netif_is_bridge_master(info->upper_dev) && info->linking) {
+		NL_SET_ERR_MSG_MOD(ext_ack,
+				   "Cannot enslave VLAN device into VLAN aware bridge");
+		return notifier_from_errno(-EINVAL);
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int
+dsa_slave_check_8021q_upper(struct net_device *dev,
+			    struct netdev_notifier_changeupper_info *info)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct net_device *br = dsa_port_bridge_dev_get(dp);
+	struct bridge_vlan_info br_info;
+	struct netlink_ext_ack *extack;
+	int err = NOTIFY_DONE;
+	u16 vid;
+
+	if (!br || !br_vlan_enabled(br))
+		return NOTIFY_DONE;
+
+	extack = netdev_notifier_info_to_extack(&info->info);
+	vid = vlan_dev_vlan_id(info->upper_dev);
+
+	/* br_vlan_get_info() returns -EINVAL or -ENOENT if the
+	 * device, respectively the VID is not found, returning
+	 * 0 means success, which is a failure for us here.
+	 */
+	err = br_vlan_get_info(br, vid, &br_info);
+	if (err == 0) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "This VLAN is already configured by the bridge");
+		return notifier_from_errno(-EBUSY);
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int
+dsa_slave_prechangeupper_sanity_check(struct net_device *dev,
+				      struct netdev_notifier_changeupper_info *info)
+{
+	struct dsa_switch *ds;
+	struct dsa_port *dp;
+	int err;
+
+	if (!dsa_slave_dev_check(dev))
+		return dsa_prevent_bridging_8021q_upper(dev, info);
+
+	dp = dsa_slave_to_port(dev);
+	ds = dp->ds;
+
+	if (ds->ops->port_prechangeupper) {
+		err = ds->ops->port_prechangeupper(ds, dp->index, info);
+		if (err)
+			return notifier_from_errno(err);
+	}
+
+	if (is_vlan_dev(info->upper_dev))
+		return dsa_slave_check_8021q_upper(dev, info);
+
+	return NOTIFY_DONE;
+}
+
+/* To be eligible as a DSA master, a LAG must have all lower interfaces be
+ * eligible DSA masters. Additionally, all LAG slaves must be DSA masters of
+ * switches in the same switch tree.
+ */
+static int dsa_lag_master_validate(struct net_device *lag_dev,
+				   struct netlink_ext_ack *extack)
+{
+	struct net_device *lower1, *lower2;
+	struct list_head *iter1, *iter2;
+
+	netdev_for_each_lower_dev(lag_dev, lower1, iter1) {
+		netdev_for_each_lower_dev(lag_dev, lower2, iter2) {
+			if (!netdev_uses_dsa(lower1) ||
+			    !netdev_uses_dsa(lower2)) {
+				NL_SET_ERR_MSG_MOD(extack,
+						   "All LAG ports must be eligible as DSA masters");
+				return notifier_from_errno(-EINVAL);
+			}
+
+			if (lower1 == lower2)
+				continue;
+
+			if (!dsa_port_tree_same(lower1->dsa_ptr,
+						lower2->dsa_ptr)) {
+				NL_SET_ERR_MSG_MOD(extack,
+						   "LAG contains DSA masters of disjoint switch trees");
+				return notifier_from_errno(-EINVAL);
+			}
+		}
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int
+dsa_master_prechangeupper_sanity_check(struct net_device *master,
+				       struct netdev_notifier_changeupper_info *info)
+{
+	struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(&info->info);
+
+	if (!netdev_uses_dsa(master))
+		return NOTIFY_DONE;
+
+	if (!info->linking)
+		return NOTIFY_DONE;
+
+	/* Allow DSA switch uppers */
+	if (dsa_slave_dev_check(info->upper_dev))
+		return NOTIFY_DONE;
+
+	/* Allow bridge uppers of DSA masters, subject to further
+	 * restrictions in dsa_bridge_prechangelower_sanity_check()
+	 */
+	if (netif_is_bridge_master(info->upper_dev))
+		return NOTIFY_DONE;
+
+	/* Allow LAG uppers, subject to further restrictions in
+	 * dsa_lag_master_prechangelower_sanity_check()
+	 */
+	if (netif_is_lag_master(info->upper_dev))
+		return dsa_lag_master_validate(info->upper_dev, extack);
+
+	NL_SET_ERR_MSG_MOD(extack,
+			   "DSA master cannot join unknown upper interfaces");
+	return notifier_from_errno(-EBUSY);
+}
+
+static int
+dsa_lag_master_prechangelower_sanity_check(struct net_device *dev,
+					   struct netdev_notifier_changeupper_info *info)
+{
+	struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(&info->info);
+	struct net_device *lag_dev = info->upper_dev;
+	struct net_device *lower;
+	struct list_head *iter;
+
+	if (!netdev_uses_dsa(lag_dev) || !netif_is_lag_master(lag_dev))
+		return NOTIFY_DONE;
+
+	if (!info->linking)
+		return NOTIFY_DONE;
+
+	if (!netdev_uses_dsa(dev)) {
+		NL_SET_ERR_MSG(extack,
+			       "Only DSA masters can join a LAG DSA master");
+		return notifier_from_errno(-EINVAL);
+	}
+
+	netdev_for_each_lower_dev(lag_dev, lower, iter) {
+		if (!dsa_port_tree_same(dev->dsa_ptr, lower->dsa_ptr)) {
+			NL_SET_ERR_MSG(extack,
+				       "Interface is DSA master for a different switch tree than this LAG");
+			return notifier_from_errno(-EINVAL);
+		}
+
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+/* Don't allow bridging of DSA masters, since the bridge layer rx_handler
+ * prevents the DSA fake ethertype handler to be invoked, so we don't get the
+ * chance to strip off and parse the DSA switch tag protocol header (the bridge
+ * layer just returns RX_HANDLER_CONSUMED, stopping RX processing for these
+ * frames).
+ * The only case where that would not be an issue is when bridging can already
+ * be offloaded, such as when the DSA master is itself a DSA or plain switchdev
+ * port, and is bridged only with other ports from the same hardware device.
+ */
+static int
+dsa_bridge_prechangelower_sanity_check(struct net_device *new_lower,
+				       struct netdev_notifier_changeupper_info *info)
+{
+	struct net_device *br = info->upper_dev;
+	struct netlink_ext_ack *extack;
+	struct net_device *lower;
+	struct list_head *iter;
+
+	if (!netif_is_bridge_master(br))
+		return NOTIFY_DONE;
+
+	if (!info->linking)
+		return NOTIFY_DONE;
+
+	extack = netdev_notifier_info_to_extack(&info->info);
+
+	netdev_for_each_lower_dev(br, lower, iter) {
+		if (!netdev_uses_dsa(new_lower) && !netdev_uses_dsa(lower))
+			continue;
+
+		if (!netdev_port_same_parent_id(lower, new_lower)) {
+			NL_SET_ERR_MSG(extack,
+				       "Cannot do software bridging with a DSA master");
+			return notifier_from_errno(-EINVAL);
+		}
+	}
+
+	return NOTIFY_DONE;
+}
+
+static void dsa_tree_migrate_ports_from_lag_master(struct dsa_switch_tree *dst,
+						   struct net_device *lag_dev)
+{
+	struct net_device *new_master = dsa_tree_find_first_master(dst);
+	struct dsa_port *dp;
+	int err;
+
+	dsa_tree_for_each_user_port(dp, dst) {
+		if (dsa_port_to_master(dp) != lag_dev)
+			continue;
+
+		err = dsa_slave_change_master(dp->slave, new_master, NULL);
+		if (err) {
+			netdev_err(dp->slave,
+				   "failed to restore master to %s: %pe\n",
+				   new_master->name, ERR_PTR(err));
+		}
+	}
+}
+
+static int dsa_master_lag_join(struct net_device *master,
+			       struct net_device *lag_dev,
+			       struct netdev_lag_upper_info *uinfo,
+			       struct netlink_ext_ack *extack)
+{
+	struct dsa_port *cpu_dp = master->dsa_ptr;
+	struct dsa_switch_tree *dst = cpu_dp->dst;
+	struct dsa_port *dp;
+	int err;
+
+	err = dsa_master_lag_setup(lag_dev, cpu_dp, uinfo, extack);
+	if (err)
+		return err;
+
+	dsa_tree_for_each_user_port(dp, dst) {
+		if (dsa_port_to_master(dp) != master)
+			continue;
+
+		err = dsa_slave_change_master(dp->slave, lag_dev, extack);
+		if (err)
+			goto restore;
+	}
+
+	return 0;
+
+restore:
+	dsa_tree_for_each_user_port_continue_reverse(dp, dst) {
+		if (dsa_port_to_master(dp) != lag_dev)
+			continue;
+
+		err = dsa_slave_change_master(dp->slave, master, NULL);
+		if (err) {
+			netdev_err(dp->slave,
+				   "failed to restore master to %s: %pe\n",
+				   master->name, ERR_PTR(err));
+		}
+	}
+
+	dsa_master_lag_teardown(lag_dev, master->dsa_ptr);
+
+	return err;
+}
+
+static void dsa_master_lag_leave(struct net_device *master,
+				 struct net_device *lag_dev)
+{
+	struct dsa_port *dp, *cpu_dp = lag_dev->dsa_ptr;
+	struct dsa_switch_tree *dst = cpu_dp->dst;
+	struct dsa_port *new_cpu_dp = NULL;
+	struct net_device *lower;
+	struct list_head *iter;
+
+	netdev_for_each_lower_dev(lag_dev, lower, iter) {
+		if (netdev_uses_dsa(lower)) {
+			new_cpu_dp = lower->dsa_ptr;
+			break;
+		}
+	}
+
+	if (new_cpu_dp) {
+		/* Update the CPU port of the user ports still under the LAG
+		 * so that dsa_port_to_master() continues to work properly
+		 */
+		dsa_tree_for_each_user_port(dp, dst)
+			if (dsa_port_to_master(dp) == lag_dev)
+				dp->cpu_dp = new_cpu_dp;
+
+		/* Update the index of the virtual CPU port to match the lowest
+		 * physical CPU port
+		 */
+		lag_dev->dsa_ptr = new_cpu_dp;
+		wmb();
+	} else {
+		/* If the LAG DSA master has no ports left, migrate back all
+		 * user ports to the first physical CPU port
+		 */
+		dsa_tree_migrate_ports_from_lag_master(dst, lag_dev);
+	}
+
+	/* This DSA master has left its LAG in any case, so let
+	 * the CPU port leave the hardware LAG as well
+	 */
+	dsa_master_lag_teardown(lag_dev, master->dsa_ptr);
+}
+
+static int dsa_master_changeupper(struct net_device *dev,
+				  struct netdev_notifier_changeupper_info *info)
+{
+	struct netlink_ext_ack *extack;
+	int err = NOTIFY_DONE;
+
+	if (!netdev_uses_dsa(dev))
+		return err;
+
+	extack = netdev_notifier_info_to_extack(&info->info);
+
+	if (netif_is_lag_master(info->upper_dev)) {
+		if (info->linking) {
+			err = dsa_master_lag_join(dev, info->upper_dev,
+						  info->upper_info, extack);
+			err = notifier_from_errno(err);
+		} else {
+			dsa_master_lag_leave(dev, info->upper_dev);
+			err = NOTIFY_OK;
+		}
+	}
+
+	return err;
+}
+
+static int dsa_slave_netdevice_event(struct notifier_block *nb,
+				     unsigned long event, void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+	switch (event) {
+	case NETDEV_PRECHANGEUPPER: {
+		struct netdev_notifier_changeupper_info *info = ptr;
+		int err;
+
+		err = dsa_slave_prechangeupper_sanity_check(dev, info);
+		if (notifier_to_errno(err))
+			return err;
+
+		err = dsa_master_prechangeupper_sanity_check(dev, info);
+		if (notifier_to_errno(err))
+			return err;
+
+		err = dsa_lag_master_prechangelower_sanity_check(dev, info);
+		if (notifier_to_errno(err))
+			return err;
+
+		err = dsa_bridge_prechangelower_sanity_check(dev, info);
+		if (notifier_to_errno(err))
+			return err;
+
+		err = dsa_slave_prechangeupper(dev, ptr);
+		if (notifier_to_errno(err))
+			return err;
+
+		err = dsa_slave_lag_prechangeupper(dev, ptr);
+		if (notifier_to_errno(err))
+			return err;
+
+		break;
+	}
+	case NETDEV_CHANGEUPPER: {
+		int err;
+
+		err = dsa_slave_changeupper(dev, ptr);
+		if (notifier_to_errno(err))
+			return err;
+
+		err = dsa_slave_lag_changeupper(dev, ptr);
+		if (notifier_to_errno(err))
+			return err;
+
+		err = dsa_master_changeupper(dev, ptr);
+		if (notifier_to_errno(err))
+			return err;
+
+		break;
+	}
+	case NETDEV_CHANGELOWERSTATE: {
+		struct netdev_notifier_changelowerstate_info *info = ptr;
+		struct dsa_port *dp;
+		int err = 0;
+
+		if (dsa_slave_dev_check(dev)) {
+			dp = dsa_slave_to_port(dev);
+
+			err = dsa_port_lag_change(dp, info->lower_state_info);
+		}
+
+		/* Mirror LAG port events on DSA masters that are in
+		 * a LAG towards their respective switch CPU ports
+		 */
+		if (netdev_uses_dsa(dev)) {
+			dp = dev->dsa_ptr;
+
+			err = dsa_port_lag_change(dp, info->lower_state_info);
+		}
+
+		return notifier_from_errno(err);
+	}
+	case NETDEV_CHANGE:
+	case NETDEV_UP: {
+		/* Track state of master port.
+		 * DSA driver may require the master port (and indirectly
+		 * the tagger) to be available for some special operation.
+		 */
+		if (netdev_uses_dsa(dev)) {
+			struct dsa_port *cpu_dp = dev->dsa_ptr;
+			struct dsa_switch_tree *dst = cpu_dp->ds->dst;
+
+			/* Track when the master port is UP */
+			dsa_tree_master_oper_state_change(dst, dev,
+							  netif_oper_up(dev));
+
+			/* Track when the master port is ready and can accept
+			 * packet.
+			 * NETDEV_UP event is not enough to flag a port as ready.
+			 * We also have to wait for linkwatch_do_dev to dev_activate
+			 * and emit a NETDEV_CHANGE event.
+			 * We check if a master port is ready by checking if the dev
+			 * have a qdisc assigned and is not noop.
+			 */
+			dsa_tree_master_admin_state_change(dst, dev,
+							   !qdisc_tx_is_noop(dev));
+
+			return NOTIFY_OK;
+		}
+
+		return NOTIFY_DONE;
+	}
+	case NETDEV_GOING_DOWN: {
+		struct dsa_port *dp, *cpu_dp;
+		struct dsa_switch_tree *dst;
+		LIST_HEAD(close_list);
+
+		if (!netdev_uses_dsa(dev))
+			return NOTIFY_DONE;
+
+		cpu_dp = dev->dsa_ptr;
+		dst = cpu_dp->ds->dst;
+
+		dsa_tree_master_admin_state_change(dst, dev, false);
+
+		list_for_each_entry(dp, &dst->ports, list) {
+			if (!dsa_port_is_user(dp))
+				continue;
+
+			if (dp->cpu_dp != cpu_dp)
+				continue;
+
+			list_add(&dp->slave->close_list, &close_list);
+		}
+
+		dev_close_many(&close_list, true);
+
+		return NOTIFY_OK;
+	}
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static void
+dsa_fdb_offload_notify(struct dsa_switchdev_event_work *switchdev_work)
+{
+	struct switchdev_notifier_fdb_info info = {};
+
+	info.addr = switchdev_work->addr;
+	info.vid = switchdev_work->vid;
+	info.offloaded = true;
+	call_switchdev_notifiers(SWITCHDEV_FDB_OFFLOADED,
+				 switchdev_work->orig_dev, &info.info, NULL);
+}
+
+static void dsa_slave_switchdev_event_work(struct work_struct *work)
+{
+	struct dsa_switchdev_event_work *switchdev_work =
+		container_of(work, struct dsa_switchdev_event_work, work);
+	const unsigned char *addr = switchdev_work->addr;
+	struct net_device *dev = switchdev_work->dev;
+	u16 vid = switchdev_work->vid;
+	struct dsa_switch *ds;
+	struct dsa_port *dp;
+	int err;
+
+	dp = dsa_slave_to_port(dev);
+	ds = dp->ds;
+
+	switch (switchdev_work->event) {
+	case SWITCHDEV_FDB_ADD_TO_DEVICE:
+		if (switchdev_work->host_addr)
+			err = dsa_port_bridge_host_fdb_add(dp, addr, vid);
+		else if (dp->lag)
+			err = dsa_port_lag_fdb_add(dp, addr, vid);
+		else
+			err = dsa_port_fdb_add(dp, addr, vid);
+		if (err) {
+			dev_err(ds->dev,
+				"port %d failed to add %pM vid %d to fdb: %d\n",
+				dp->index, addr, vid, err);
+			break;
+		}
+		dsa_fdb_offload_notify(switchdev_work);
+		break;
+
+	case SWITCHDEV_FDB_DEL_TO_DEVICE:
+		if (switchdev_work->host_addr)
+			err = dsa_port_bridge_host_fdb_del(dp, addr, vid);
+		else if (dp->lag)
+			err = dsa_port_lag_fdb_del(dp, addr, vid);
+		else
+			err = dsa_port_fdb_del(dp, addr, vid);
+		if (err) {
+			dev_err(ds->dev,
+				"port %d failed to delete %pM vid %d from fdb: %d\n",
+				dp->index, addr, vid, err);
+		}
+
+		break;
+	}
+
+	kfree(switchdev_work);
+}
+
+static bool dsa_foreign_dev_check(const struct net_device *dev,
+				  const struct net_device *foreign_dev)
+{
+	const struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch_tree *dst = dp->ds->dst;
+
+	if (netif_is_bridge_master(foreign_dev))
+		return !dsa_tree_offloads_bridge_dev(dst, foreign_dev);
+
+	if (netif_is_bridge_port(foreign_dev))
+		return !dsa_tree_offloads_bridge_port(dst, foreign_dev);
+
+	/* Everything else is foreign */
+	return true;
+}
+
+static int dsa_slave_fdb_event(struct net_device *dev,
+			       struct net_device *orig_dev,
+			       unsigned long event, const void *ctx,
+			       const struct switchdev_notifier_fdb_info *fdb_info)
+{
+	struct dsa_switchdev_event_work *switchdev_work;
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	bool host_addr = fdb_info->is_local;
+	struct dsa_switch *ds = dp->ds;
+
+	if (ctx && ctx != dp)
+		return 0;
+
+	if (!dp->bridge)
+		return 0;
+
+	if (switchdev_fdb_is_dynamically_learned(fdb_info)) {
+		if (dsa_port_offloads_bridge_port(dp, orig_dev))
+			return 0;
+
+		/* FDB entries learned by the software bridge or by foreign
+		 * bridge ports should be installed as host addresses only if
+		 * the driver requests assisted learning.
+		 */
+		if (!ds->assisted_learning_on_cpu_port)
+			return 0;
+	}
+
+	/* Also treat FDB entries on foreign interfaces bridged with us as host
+	 * addresses.
+	 */
+	if (dsa_foreign_dev_check(dev, orig_dev))
+		host_addr = true;
+
+	/* Check early that we're not doing work in vain.
+	 * Host addresses on LAG ports still require regular FDB ops,
+	 * since the CPU port isn't in a LAG.
+	 */
+	if (dp->lag && !host_addr) {
+		if (!ds->ops->lag_fdb_add || !ds->ops->lag_fdb_del)
+			return -EOPNOTSUPP;
+	} else {
+		if (!ds->ops->port_fdb_add || !ds->ops->port_fdb_del)
+			return -EOPNOTSUPP;
+	}
+
+	switchdev_work = kzalloc(sizeof(*switchdev_work), GFP_ATOMIC);
+	if (!switchdev_work)
+		return -ENOMEM;
+
+	netdev_dbg(dev, "%s FDB entry towards %s, addr %pM vid %d%s\n",
+		   event == SWITCHDEV_FDB_ADD_TO_DEVICE ? "Adding" : "Deleting",
+		   orig_dev->name, fdb_info->addr, fdb_info->vid,
+		   host_addr ? " as host address" : "");
+
+	INIT_WORK(&switchdev_work->work, dsa_slave_switchdev_event_work);
+	switchdev_work->event = event;
+	switchdev_work->dev = dev;
+	switchdev_work->orig_dev = orig_dev;
+
+	ether_addr_copy(switchdev_work->addr, fdb_info->addr);
+	switchdev_work->vid = fdb_info->vid;
+	switchdev_work->host_addr = host_addr;
+
+	dsa_schedule_work(&switchdev_work->work);
+
+	return 0;
+}
+
+/* Called under rcu_read_lock() */
+static int dsa_slave_switchdev_event(struct notifier_block *unused,
+				     unsigned long event, void *ptr)
+{
+	struct net_device *dev = switchdev_notifier_info_to_dev(ptr);
+	int err;
+
+	switch (event) {
+	case SWITCHDEV_PORT_ATTR_SET:
+		err = switchdev_handle_port_attr_set(dev, ptr,
+						     dsa_slave_dev_check,
+						     dsa_slave_port_attr_set);
+		return notifier_from_errno(err);
+	case SWITCHDEV_FDB_ADD_TO_DEVICE:
+	case SWITCHDEV_FDB_DEL_TO_DEVICE:
+		err = switchdev_handle_fdb_event_to_device(dev, event, ptr,
+							   dsa_slave_dev_check,
+							   dsa_foreign_dev_check,
+							   dsa_slave_fdb_event);
+		return notifier_from_errno(err);
+	default:
+		return NOTIFY_DONE;
+	}
+
+	return NOTIFY_OK;
+}
+
+static int dsa_slave_switchdev_blocking_event(struct notifier_block *unused,
+					      unsigned long event, void *ptr)
+{
+	struct net_device *dev = switchdev_notifier_info_to_dev(ptr);
+	int err;
+
+	switch (event) {
+	case SWITCHDEV_PORT_OBJ_ADD:
+		err = switchdev_handle_port_obj_add_foreign(dev, ptr,
+							    dsa_slave_dev_check,
+							    dsa_foreign_dev_check,
+							    dsa_slave_port_obj_add);
+		return notifier_from_errno(err);
+	case SWITCHDEV_PORT_OBJ_DEL:
+		err = switchdev_handle_port_obj_del_foreign(dev, ptr,
+							    dsa_slave_dev_check,
+							    dsa_foreign_dev_check,
+							    dsa_slave_port_obj_del);
+		return notifier_from_errno(err);
+	case SWITCHDEV_PORT_ATTR_SET:
+		err = switchdev_handle_port_attr_set(dev, ptr,
+						     dsa_slave_dev_check,
+						     dsa_slave_port_attr_set);
+		return notifier_from_errno(err);
+	}
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block dsa_slave_nb __read_mostly = {
+	.notifier_call  = dsa_slave_netdevice_event,
+};
+
+struct notifier_block dsa_slave_switchdev_notifier = {
+	.notifier_call = dsa_slave_switchdev_event,
+};
+
+struct notifier_block dsa_slave_switchdev_blocking_notifier = {
+	.notifier_call = dsa_slave_switchdev_blocking_event,
+};
+
+int dsa_slave_register_notifier(void)
+{
+	struct notifier_block *nb;
+	int err;
+
+	err = register_netdevice_notifier(&dsa_slave_nb);
+	if (err)
+		return err;
+
+	err = register_switchdev_notifier(&dsa_slave_switchdev_notifier);
+	if (err)
+		goto err_switchdev_nb;
+
+	nb = &dsa_slave_switchdev_blocking_notifier;
+	err = register_switchdev_blocking_notifier(nb);
+	if (err)
+		goto err_switchdev_blocking_nb;
+
+	return 0;
+
+err_switchdev_blocking_nb:
+	unregister_switchdev_notifier(&dsa_slave_switchdev_notifier);
+err_switchdev_nb:
+	unregister_netdevice_notifier(&dsa_slave_nb);
+	return err;
+}
+
+void dsa_slave_unregister_notifier(void)
+{
+	struct notifier_block *nb;
+	int err;
+
+	nb = &dsa_slave_switchdev_blocking_notifier;
+	err = unregister_switchdev_blocking_notifier(nb);
+	if (err)
+		pr_err("DSA: failed to unregister switchdev blocking notifier (%d)\n", err);
+
+	err = unregister_switchdev_notifier(&dsa_slave_switchdev_notifier);
+	if (err)
+		pr_err("DSA: failed to unregister switchdev notifier (%d)\n", err);
+
+	err = unregister_netdevice_notifier(&dsa_slave_nb);
+	if (err)
+		pr_err("DSA: failed to unregister slave notifier (%d)\n", err);
+}
diff --git a/net/dsa/switch.c b/net/dsa/switch.c
new file mode 100644
index 000000000..ce56acdba
--- /dev/null
+++ b/net/dsa/switch.c
@@ -0,0 +1,1030 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Handling of a single switch chip, part of a switch fabric
+ *
+ * Copyright (c) 2017 Savoir-faire Linux Inc.
+ *	Vivien Didelot <vivien.didelot@savoirfairelinux.com>
+ */
+
+#include <linux/if_bridge.h>
+#include <linux/netdevice.h>
+#include <linux/notifier.h>
+#include <linux/if_vlan.h>
+#include <net/switchdev.h>
+
+#include "dsa_priv.h"
+
+static unsigned int dsa_switch_fastest_ageing_time(struct dsa_switch *ds,
+						   unsigned int ageing_time)
+{
+	struct dsa_port *dp;
+
+	dsa_switch_for_each_port(dp, ds)
+		if (dp->ageing_time && dp->ageing_time < ageing_time)
+			ageing_time = dp->ageing_time;
+
+	return ageing_time;
+}
+
+static int dsa_switch_ageing_time(struct dsa_switch *ds,
+				  struct dsa_notifier_ageing_time_info *info)
+{
+	unsigned int ageing_time = info->ageing_time;
+
+	if (ds->ageing_time_min && ageing_time < ds->ageing_time_min)
+		return -ERANGE;
+
+	if (ds->ageing_time_max && ageing_time > ds->ageing_time_max)
+		return -ERANGE;
+
+	/* Program the fastest ageing time in case of multiple bridges */
+	ageing_time = dsa_switch_fastest_ageing_time(ds, ageing_time);
+
+	if (ds->ops->set_ageing_time)
+		return ds->ops->set_ageing_time(ds, ageing_time);
+
+	return 0;
+}
+
+static bool dsa_port_mtu_match(struct dsa_port *dp,
+			       struct dsa_notifier_mtu_info *info)
+{
+	return dp == info->dp || dsa_port_is_dsa(dp) || dsa_port_is_cpu(dp);
+}
+
+static int dsa_switch_mtu(struct dsa_switch *ds,
+			  struct dsa_notifier_mtu_info *info)
+{
+	struct dsa_port *dp;
+	int ret;
+
+	if (!ds->ops->port_change_mtu)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_mtu_match(dp, info)) {
+			ret = ds->ops->port_change_mtu(ds, dp->index,
+						       info->mtu);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_bridge_join(struct dsa_switch *ds,
+				  struct dsa_notifier_bridge_info *info)
+{
+	int err;
+
+	if (info->dp->ds == ds) {
+		if (!ds->ops->port_bridge_join)
+			return -EOPNOTSUPP;
+
+		err = ds->ops->port_bridge_join(ds, info->dp->index,
+						info->bridge,
+						&info->tx_fwd_offload,
+						info->extack);
+		if (err)
+			return err;
+	}
+
+	if (info->dp->ds != ds && ds->ops->crosschip_bridge_join) {
+		err = ds->ops->crosschip_bridge_join(ds,
+						     info->dp->ds->dst->index,
+						     info->dp->ds->index,
+						     info->dp->index,
+						     info->bridge,
+						     info->extack);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int dsa_switch_bridge_leave(struct dsa_switch *ds,
+				   struct dsa_notifier_bridge_info *info)
+{
+	if (info->dp->ds == ds && ds->ops->port_bridge_leave)
+		ds->ops->port_bridge_leave(ds, info->dp->index, info->bridge);
+
+	if (info->dp->ds != ds && ds->ops->crosschip_bridge_leave)
+		ds->ops->crosschip_bridge_leave(ds, info->dp->ds->dst->index,
+						info->dp->ds->index,
+						info->dp->index,
+						info->bridge);
+
+	return 0;
+}
+
+/* Matches for all upstream-facing ports (the CPU port and all upstream-facing
+ * DSA links) that sit between the targeted port on which the notifier was
+ * emitted and its dedicated CPU port.
+ */
+static bool dsa_port_host_address_match(struct dsa_port *dp,
+					const struct dsa_port *targeted_dp)
+{
+	struct dsa_port *cpu_dp = targeted_dp->cpu_dp;
+
+	if (dsa_switch_is_upstream_of(dp->ds, targeted_dp->ds))
+		return dp->index == dsa_towards_port(dp->ds, cpu_dp->ds->index,
+						     cpu_dp->index);
+
+	return false;
+}
+
+static struct dsa_mac_addr *dsa_mac_addr_find(struct list_head *addr_list,
+					      const unsigned char *addr, u16 vid,
+					      struct dsa_db db)
+{
+	struct dsa_mac_addr *a;
+
+	list_for_each_entry(a, addr_list, list)
+		if (ether_addr_equal(a->addr, addr) && a->vid == vid &&
+		    dsa_db_equal(&a->db, &db))
+			return a;
+
+	return NULL;
+}
+
+static int dsa_port_do_mdb_add(struct dsa_port *dp,
+			       const struct switchdev_obj_port_mdb *mdb,
+			       struct dsa_db db)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_mac_addr *a;
+	int port = dp->index;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
+		return ds->ops->port_mdb_add(ds, port, mdb, db);
+
+	mutex_lock(&dp->addr_lists_lock);
+
+	a = dsa_mac_addr_find(&dp->mdbs, mdb->addr, mdb->vid, db);
+	if (a) {
+		refcount_inc(&a->refcount);
+		goto out;
+	}
+
+	a = kzalloc(sizeof(*a), GFP_KERNEL);
+	if (!a) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ds->ops->port_mdb_add(ds, port, mdb, db);
+	if (err) {
+		kfree(a);
+		goto out;
+	}
+
+	ether_addr_copy(a->addr, mdb->addr);
+	a->vid = mdb->vid;
+	a->db = db;
+	refcount_set(&a->refcount, 1);
+	list_add_tail(&a->list, &dp->mdbs);
+
+out:
+	mutex_unlock(&dp->addr_lists_lock);
+
+	return err;
+}
+
+static int dsa_port_do_mdb_del(struct dsa_port *dp,
+			       const struct switchdev_obj_port_mdb *mdb,
+			       struct dsa_db db)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_mac_addr *a;
+	int port = dp->index;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
+		return ds->ops->port_mdb_del(ds, port, mdb, db);
+
+	mutex_lock(&dp->addr_lists_lock);
+
+	a = dsa_mac_addr_find(&dp->mdbs, mdb->addr, mdb->vid, db);
+	if (!a) {
+		err = -ENOENT;
+		goto out;
+	}
+
+	if (!refcount_dec_and_test(&a->refcount))
+		goto out;
+
+	err = ds->ops->port_mdb_del(ds, port, mdb, db);
+	if (err) {
+		refcount_set(&a->refcount, 1);
+		goto out;
+	}
+
+	list_del(&a->list);
+	kfree(a);
+
+out:
+	mutex_unlock(&dp->addr_lists_lock);
+
+	return err;
+}
+
+static int dsa_port_do_fdb_add(struct dsa_port *dp, const unsigned char *addr,
+			       u16 vid, struct dsa_db db)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_mac_addr *a;
+	int port = dp->index;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
+		return ds->ops->port_fdb_add(ds, port, addr, vid, db);
+
+	mutex_lock(&dp->addr_lists_lock);
+
+	a = dsa_mac_addr_find(&dp->fdbs, addr, vid, db);
+	if (a) {
+		refcount_inc(&a->refcount);
+		goto out;
+	}
+
+	a = kzalloc(sizeof(*a), GFP_KERNEL);
+	if (!a) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ds->ops->port_fdb_add(ds, port, addr, vid, db);
+	if (err) {
+		kfree(a);
+		goto out;
+	}
+
+	ether_addr_copy(a->addr, addr);
+	a->vid = vid;
+	a->db = db;
+	refcount_set(&a->refcount, 1);
+	list_add_tail(&a->list, &dp->fdbs);
+
+out:
+	mutex_unlock(&dp->addr_lists_lock);
+
+	return err;
+}
+
+static int dsa_port_do_fdb_del(struct dsa_port *dp, const unsigned char *addr,
+			       u16 vid, struct dsa_db db)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_mac_addr *a;
+	int port = dp->index;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
+		return ds->ops->port_fdb_del(ds, port, addr, vid, db);
+
+	mutex_lock(&dp->addr_lists_lock);
+
+	a = dsa_mac_addr_find(&dp->fdbs, addr, vid, db);
+	if (!a) {
+		err = -ENOENT;
+		goto out;
+	}
+
+	if (!refcount_dec_and_test(&a->refcount))
+		goto out;
+
+	err = ds->ops->port_fdb_del(ds, port, addr, vid, db);
+	if (err) {
+		refcount_set(&a->refcount, 1);
+		goto out;
+	}
+
+	list_del(&a->list);
+	kfree(a);
+
+out:
+	mutex_unlock(&dp->addr_lists_lock);
+
+	return err;
+}
+
+static int dsa_switch_do_lag_fdb_add(struct dsa_switch *ds, struct dsa_lag *lag,
+				     const unsigned char *addr, u16 vid,
+				     struct dsa_db db)
+{
+	struct dsa_mac_addr *a;
+	int err = 0;
+
+	mutex_lock(&lag->fdb_lock);
+
+	a = dsa_mac_addr_find(&lag->fdbs, addr, vid, db);
+	if (a) {
+		refcount_inc(&a->refcount);
+		goto out;
+	}
+
+	a = kzalloc(sizeof(*a), GFP_KERNEL);
+	if (!a) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ds->ops->lag_fdb_add(ds, *lag, addr, vid, db);
+	if (err) {
+		kfree(a);
+		goto out;
+	}
+
+	ether_addr_copy(a->addr, addr);
+	a->vid = vid;
+	a->db = db;
+	refcount_set(&a->refcount, 1);
+	list_add_tail(&a->list, &lag->fdbs);
+
+out:
+	mutex_unlock(&lag->fdb_lock);
+
+	return err;
+}
+
+static int dsa_switch_do_lag_fdb_del(struct dsa_switch *ds, struct dsa_lag *lag,
+				     const unsigned char *addr, u16 vid,
+				     struct dsa_db db)
+{
+	struct dsa_mac_addr *a;
+	int err = 0;
+
+	mutex_lock(&lag->fdb_lock);
+
+	a = dsa_mac_addr_find(&lag->fdbs, addr, vid, db);
+	if (!a) {
+		err = -ENOENT;
+		goto out;
+	}
+
+	if (!refcount_dec_and_test(&a->refcount))
+		goto out;
+
+	err = ds->ops->lag_fdb_del(ds, *lag, addr, vid, db);
+	if (err) {
+		refcount_set(&a->refcount, 1);
+		goto out;
+	}
+
+	list_del(&a->list);
+	kfree(a);
+
+out:
+	mutex_unlock(&lag->fdb_lock);
+
+	return err;
+}
+
+static int dsa_switch_host_fdb_add(struct dsa_switch *ds,
+				   struct dsa_notifier_fdb_info *info)
+{
+	struct dsa_port *dp;
+	int err = 0;
+
+	if (!ds->ops->port_fdb_add)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_address_match(dp, info->dp)) {
+			if (dsa_port_is_cpu(dp) && info->dp->cpu_port_in_lag) {
+				err = dsa_switch_do_lag_fdb_add(ds, dp->lag,
+								info->addr,
+								info->vid,
+								info->db);
+			} else {
+				err = dsa_port_do_fdb_add(dp, info->addr,
+							  info->vid, info->db);
+			}
+			if (err)
+				break;
+		}
+	}
+
+	return err;
+}
+
+static int dsa_switch_host_fdb_del(struct dsa_switch *ds,
+				   struct dsa_notifier_fdb_info *info)
+{
+	struct dsa_port *dp;
+	int err = 0;
+
+	if (!ds->ops->port_fdb_del)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_address_match(dp, info->dp)) {
+			if (dsa_port_is_cpu(dp) && info->dp->cpu_port_in_lag) {
+				err = dsa_switch_do_lag_fdb_del(ds, dp->lag,
+								info->addr,
+								info->vid,
+								info->db);
+			} else {
+				err = dsa_port_do_fdb_del(dp, info->addr,
+							  info->vid, info->db);
+			}
+			if (err)
+				break;
+		}
+	}
+
+	return err;
+}
+
+static int dsa_switch_fdb_add(struct dsa_switch *ds,
+			      struct dsa_notifier_fdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
+	struct dsa_port *dp = dsa_to_port(ds, port);
+
+	if (!ds->ops->port_fdb_add)
+		return -EOPNOTSUPP;
+
+	return dsa_port_do_fdb_add(dp, info->addr, info->vid, info->db);
+}
+
+static int dsa_switch_fdb_del(struct dsa_switch *ds,
+			      struct dsa_notifier_fdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
+	struct dsa_port *dp = dsa_to_port(ds, port);
+
+	if (!ds->ops->port_fdb_del)
+		return -EOPNOTSUPP;
+
+	return dsa_port_do_fdb_del(dp, info->addr, info->vid, info->db);
+}
+
+static int dsa_switch_lag_fdb_add(struct dsa_switch *ds,
+				  struct dsa_notifier_lag_fdb_info *info)
+{
+	struct dsa_port *dp;
+
+	if (!ds->ops->lag_fdb_add)
+		return -EOPNOTSUPP;
+
+	/* Notify switch only if it has a port in this LAG */
+	dsa_switch_for_each_port(dp, ds)
+		if (dsa_port_offloads_lag(dp, info->lag))
+			return dsa_switch_do_lag_fdb_add(ds, info->lag,
+							 info->addr, info->vid,
+							 info->db);
+
+	return 0;
+}
+
+static int dsa_switch_lag_fdb_del(struct dsa_switch *ds,
+				  struct dsa_notifier_lag_fdb_info *info)
+{
+	struct dsa_port *dp;
+
+	if (!ds->ops->lag_fdb_del)
+		return -EOPNOTSUPP;
+
+	/* Notify switch only if it has a port in this LAG */
+	dsa_switch_for_each_port(dp, ds)
+		if (dsa_port_offloads_lag(dp, info->lag))
+			return dsa_switch_do_lag_fdb_del(ds, info->lag,
+							 info->addr, info->vid,
+							 info->db);
+
+	return 0;
+}
+
+static int dsa_switch_lag_change(struct dsa_switch *ds,
+				 struct dsa_notifier_lag_info *info)
+{
+	if (info->dp->ds == ds && ds->ops->port_lag_change)
+		return ds->ops->port_lag_change(ds, info->dp->index);
+
+	if (info->dp->ds != ds && ds->ops->crosschip_lag_change)
+		return ds->ops->crosschip_lag_change(ds, info->dp->ds->index,
+						     info->dp->index);
+
+	return 0;
+}
+
+static int dsa_switch_lag_join(struct dsa_switch *ds,
+			       struct dsa_notifier_lag_info *info)
+{
+	if (info->dp->ds == ds && ds->ops->port_lag_join)
+		return ds->ops->port_lag_join(ds, info->dp->index, info->lag,
+					      info->info, info->extack);
+
+	if (info->dp->ds != ds && ds->ops->crosschip_lag_join)
+		return ds->ops->crosschip_lag_join(ds, info->dp->ds->index,
+						   info->dp->index, info->lag,
+						   info->info, info->extack);
+
+	return -EOPNOTSUPP;
+}
+
+static int dsa_switch_lag_leave(struct dsa_switch *ds,
+				struct dsa_notifier_lag_info *info)
+{
+	if (info->dp->ds == ds && ds->ops->port_lag_leave)
+		return ds->ops->port_lag_leave(ds, info->dp->index, info->lag);
+
+	if (info->dp->ds != ds && ds->ops->crosschip_lag_leave)
+		return ds->ops->crosschip_lag_leave(ds, info->dp->ds->index,
+						    info->dp->index, info->lag);
+
+	return -EOPNOTSUPP;
+}
+
+static int dsa_switch_mdb_add(struct dsa_switch *ds,
+			      struct dsa_notifier_mdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
+	struct dsa_port *dp = dsa_to_port(ds, port);
+
+	if (!ds->ops->port_mdb_add)
+		return -EOPNOTSUPP;
+
+	return dsa_port_do_mdb_add(dp, info->mdb, info->db);
+}
+
+static int dsa_switch_mdb_del(struct dsa_switch *ds,
+			      struct dsa_notifier_mdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
+	struct dsa_port *dp = dsa_to_port(ds, port);
+
+	if (!ds->ops->port_mdb_del)
+		return -EOPNOTSUPP;
+
+	return dsa_port_do_mdb_del(dp, info->mdb, info->db);
+}
+
+static int dsa_switch_host_mdb_add(struct dsa_switch *ds,
+				   struct dsa_notifier_mdb_info *info)
+{
+	struct dsa_port *dp;
+	int err = 0;
+
+	if (!ds->ops->port_mdb_add)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_address_match(dp, info->dp)) {
+			err = dsa_port_do_mdb_add(dp, info->mdb, info->db);
+			if (err)
+				break;
+		}
+	}
+
+	return err;
+}
+
+static int dsa_switch_host_mdb_del(struct dsa_switch *ds,
+				   struct dsa_notifier_mdb_info *info)
+{
+	struct dsa_port *dp;
+	int err = 0;
+
+	if (!ds->ops->port_mdb_del)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_address_match(dp, info->dp)) {
+			err = dsa_port_do_mdb_del(dp, info->mdb, info->db);
+			if (err)
+				break;
+		}
+	}
+
+	return err;
+}
+
+/* Port VLANs match on the targeted port and on all DSA ports */
+static bool dsa_port_vlan_match(struct dsa_port *dp,
+				struct dsa_notifier_vlan_info *info)
+{
+	return dsa_port_is_dsa(dp) || dp == info->dp;
+}
+
+/* Host VLANs match on the targeted port's CPU port, and on all DSA ports
+ * (upstream and downstream) of that switch and its upstream switches.
+ */
+static bool dsa_port_host_vlan_match(struct dsa_port *dp,
+				     const struct dsa_port *targeted_dp)
+{
+	struct dsa_port *cpu_dp = targeted_dp->cpu_dp;
+
+	if (dsa_switch_is_upstream_of(dp->ds, targeted_dp->ds))
+		return dsa_port_is_dsa(dp) || dp == cpu_dp;
+
+	return false;
+}
+
+static struct dsa_vlan *dsa_vlan_find(struct list_head *vlan_list,
+				      const struct switchdev_obj_port_vlan *vlan)
+{
+	struct dsa_vlan *v;
+
+	list_for_each_entry(v, vlan_list, list)
+		if (v->vid == vlan->vid)
+			return v;
+
+	return NULL;
+}
+
+static int dsa_port_do_vlan_add(struct dsa_port *dp,
+				const struct switchdev_obj_port_vlan *vlan,
+				struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+	struct dsa_vlan *v;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports. */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
+		return ds->ops->port_vlan_add(ds, port, vlan, extack);
+
+	/* No need to propagate on shared ports the existing VLANs that were
+	 * re-notified after just the flags have changed. This would cause a
+	 * refcount bump which we need to avoid, since it unbalances the
+	 * additions with the deletions.
+	 */
+	if (vlan->changed)
+		return 0;
+
+	mutex_lock(&dp->vlans_lock);
+
+	v = dsa_vlan_find(&dp->vlans, vlan);
+	if (v) {
+		refcount_inc(&v->refcount);
+		goto out;
+	}
+
+	v = kzalloc(sizeof(*v), GFP_KERNEL);
+	if (!v) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ds->ops->port_vlan_add(ds, port, vlan, extack);
+	if (err) {
+		kfree(v);
+		goto out;
+	}
+
+	v->vid = vlan->vid;
+	refcount_set(&v->refcount, 1);
+	list_add_tail(&v->list, &dp->vlans);
+
+out:
+	mutex_unlock(&dp->vlans_lock);
+
+	return err;
+}
+
+static int dsa_port_do_vlan_del(struct dsa_port *dp,
+				const struct switchdev_obj_port_vlan *vlan)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+	struct dsa_vlan *v;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
+		return ds->ops->port_vlan_del(ds, port, vlan);
+
+	mutex_lock(&dp->vlans_lock);
+
+	v = dsa_vlan_find(&dp->vlans, vlan);
+	if (!v) {
+		err = -ENOENT;
+		goto out;
+	}
+
+	if (!refcount_dec_and_test(&v->refcount))
+		goto out;
+
+	err = ds->ops->port_vlan_del(ds, port, vlan);
+	if (err) {
+		refcount_set(&v->refcount, 1);
+		goto out;
+	}
+
+	list_del(&v->list);
+	kfree(v);
+
+out:
+	mutex_unlock(&dp->vlans_lock);
+
+	return err;
+}
+
+static int dsa_switch_vlan_add(struct dsa_switch *ds,
+			       struct dsa_notifier_vlan_info *info)
+{
+	struct dsa_port *dp;
+	int err;
+
+	if (!ds->ops->port_vlan_add)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_vlan_match(dp, info)) {
+			err = dsa_port_do_vlan_add(dp, info->vlan,
+						   info->extack);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_vlan_del(struct dsa_switch *ds,
+			       struct dsa_notifier_vlan_info *info)
+{
+	struct dsa_port *dp;
+	int err;
+
+	if (!ds->ops->port_vlan_del)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_vlan_match(dp, info)) {
+			err = dsa_port_do_vlan_del(dp, info->vlan);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_host_vlan_add(struct dsa_switch *ds,
+				    struct dsa_notifier_vlan_info *info)
+{
+	struct dsa_port *dp;
+	int err;
+
+	if (!ds->ops->port_vlan_add)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_vlan_match(dp, info->dp)) {
+			err = dsa_port_do_vlan_add(dp, info->vlan,
+						   info->extack);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_host_vlan_del(struct dsa_switch *ds,
+				    struct dsa_notifier_vlan_info *info)
+{
+	struct dsa_port *dp;
+	int err;
+
+	if (!ds->ops->port_vlan_del)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_vlan_match(dp, info->dp)) {
+			err = dsa_port_do_vlan_del(dp, info->vlan);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_change_tag_proto(struct dsa_switch *ds,
+				       struct dsa_notifier_tag_proto_info *info)
+{
+	const struct dsa_device_ops *tag_ops = info->tag_ops;
+	struct dsa_port *dp, *cpu_dp;
+	int err;
+
+	if (!ds->ops->change_tag_protocol)
+		return -EOPNOTSUPP;
+
+	ASSERT_RTNL();
+
+	err = ds->ops->change_tag_protocol(ds, tag_ops->proto);
+	if (err)
+		return err;
+
+	dsa_switch_for_each_cpu_port(cpu_dp, ds)
+		dsa_port_set_tag_protocol(cpu_dp, tag_ops);
+
+	/* Now that changing the tag protocol can no longer fail, let's update
+	 * the remaining bits which are "duplicated for faster access", and the
+	 * bits that depend on the tagger, such as the MTU.
+	 */
+	dsa_switch_for_each_user_port(dp, ds) {
+		struct net_device *slave = dp->slave;
+
+		dsa_slave_setup_tagger(slave);
+
+		/* rtnl_mutex is held in dsa_tree_change_tag_proto */
+		dsa_slave_change_mtu(slave, slave->mtu);
+	}
+
+	return 0;
+}
+
+/* We use the same cross-chip notifiers to inform both the tagger side, as well
+ * as the switch side, of connection and disconnection events.
+ * Since ds->tagger_data is owned by the tagger, it isn't a hard error if the
+ * switch side doesn't support connecting to this tagger, and therefore, the
+ * fact that we don't disconnect the tagger side doesn't constitute a memory
+ * leak: the tagger will still operate with persistent per-switch memory, just
+ * with the switch side unconnected to it. What does constitute a hard error is
+ * when the switch side supports connecting but fails.
+ */
+static int
+dsa_switch_connect_tag_proto(struct dsa_switch *ds,
+			     struct dsa_notifier_tag_proto_info *info)
+{
+	const struct dsa_device_ops *tag_ops = info->tag_ops;
+	int err;
+
+	/* Notify the new tagger about the connection to this switch */
+	if (tag_ops->connect) {
+		err = tag_ops->connect(ds);
+		if (err)
+			return err;
+	}
+
+	if (!ds->ops->connect_tag_protocol)
+		return -EOPNOTSUPP;
+
+	/* Notify the switch about the connection to the new tagger */
+	err = ds->ops->connect_tag_protocol(ds, tag_ops->proto);
+	if (err) {
+		/* Revert the new tagger's connection to this tree */
+		if (tag_ops->disconnect)
+			tag_ops->disconnect(ds);
+		return err;
+	}
+
+	return 0;
+}
+
+static int
+dsa_switch_disconnect_tag_proto(struct dsa_switch *ds,
+				struct dsa_notifier_tag_proto_info *info)
+{
+	const struct dsa_device_ops *tag_ops = info->tag_ops;
+
+	/* Notify the tagger about the disconnection from this switch */
+	if (tag_ops->disconnect && ds->tagger_data)
+		tag_ops->disconnect(ds);
+
+	/* No need to notify the switch, since it shouldn't have any
+	 * resources to tear down
+	 */
+	return 0;
+}
+
+static int
+dsa_switch_master_state_change(struct dsa_switch *ds,
+			       struct dsa_notifier_master_state_info *info)
+{
+	if (!ds->ops->master_state_change)
+		return 0;
+
+	ds->ops->master_state_change(ds, info->master, info->operational);
+
+	return 0;
+}
+
+static int dsa_switch_event(struct notifier_block *nb,
+			    unsigned long event, void *info)
+{
+	struct dsa_switch *ds = container_of(nb, struct dsa_switch, nb);
+	int err;
+
+	switch (event) {
+	case DSA_NOTIFIER_AGEING_TIME:
+		err = dsa_switch_ageing_time(ds, info);
+		break;
+	case DSA_NOTIFIER_BRIDGE_JOIN:
+		err = dsa_switch_bridge_join(ds, info);
+		break;
+	case DSA_NOTIFIER_BRIDGE_LEAVE:
+		err = dsa_switch_bridge_leave(ds, info);
+		break;
+	case DSA_NOTIFIER_FDB_ADD:
+		err = dsa_switch_fdb_add(ds, info);
+		break;
+	case DSA_NOTIFIER_FDB_DEL:
+		err = dsa_switch_fdb_del(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_FDB_ADD:
+		err = dsa_switch_host_fdb_add(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_FDB_DEL:
+		err = dsa_switch_host_fdb_del(ds, info);
+		break;
+	case DSA_NOTIFIER_LAG_FDB_ADD:
+		err = dsa_switch_lag_fdb_add(ds, info);
+		break;
+	case DSA_NOTIFIER_LAG_FDB_DEL:
+		err = dsa_switch_lag_fdb_del(ds, info);
+		break;
+	case DSA_NOTIFIER_LAG_CHANGE:
+		err = dsa_switch_lag_change(ds, info);
+		break;
+	case DSA_NOTIFIER_LAG_JOIN:
+		err = dsa_switch_lag_join(ds, info);
+		break;
+	case DSA_NOTIFIER_LAG_LEAVE:
+		err = dsa_switch_lag_leave(ds, info);
+		break;
+	case DSA_NOTIFIER_MDB_ADD:
+		err = dsa_switch_mdb_add(ds, info);
+		break;
+	case DSA_NOTIFIER_MDB_DEL:
+		err = dsa_switch_mdb_del(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_MDB_ADD:
+		err = dsa_switch_host_mdb_add(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_MDB_DEL:
+		err = dsa_switch_host_mdb_del(ds, info);
+		break;
+	case DSA_NOTIFIER_VLAN_ADD:
+		err = dsa_switch_vlan_add(ds, info);
+		break;
+	case DSA_NOTIFIER_VLAN_DEL:
+		err = dsa_switch_vlan_del(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_VLAN_ADD:
+		err = dsa_switch_host_vlan_add(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_VLAN_DEL:
+		err = dsa_switch_host_vlan_del(ds, info);
+		break;
+	case DSA_NOTIFIER_MTU:
+		err = dsa_switch_mtu(ds, info);
+		break;
+	case DSA_NOTIFIER_TAG_PROTO:
+		err = dsa_switch_change_tag_proto(ds, info);
+		break;
+	case DSA_NOTIFIER_TAG_PROTO_CONNECT:
+		err = dsa_switch_connect_tag_proto(ds, info);
+		break;
+	case DSA_NOTIFIER_TAG_PROTO_DISCONNECT:
+		err = dsa_switch_disconnect_tag_proto(ds, info);
+		break;
+	case DSA_NOTIFIER_TAG_8021Q_VLAN_ADD:
+		err = dsa_switch_tag_8021q_vlan_add(ds, info);
+		break;
+	case DSA_NOTIFIER_TAG_8021Q_VLAN_DEL:
+		err = dsa_switch_tag_8021q_vlan_del(ds, info);
+		break;
+	case DSA_NOTIFIER_MASTER_STATE_CHANGE:
+		err = dsa_switch_master_state_change(ds, info);
+		break;
+	default:
+		err = -EOPNOTSUPP;
+		break;
+	}
+
+	if (err)
+		dev_dbg(ds->dev, "breaking chain for DSA event %lu (%d)\n",
+			event, err);
+
+	return notifier_from_errno(err);
+}
+
+int dsa_switch_register_notifier(struct dsa_switch *ds)
+{
+	ds->nb.notifier_call = dsa_switch_event;
+
+	return raw_notifier_chain_register(&ds->dst->nh, &ds->nb);
+}
+
+void dsa_switch_unregister_notifier(struct dsa_switch *ds)
+{
+	int err;
+
+	err = raw_notifier_chain_unregister(&ds->dst->nh, &ds->nb);
+	if (err)
+		dev_err(ds->dev, "failed to unregister notifier (%d)\n", err);
+}
diff --git a/net/dsa/tag_8021q.c b/net/dsa/tag_8021q.c
new file mode 100644
index 000000000..89371b164
--- /dev/null
+++ b/net/dsa/tag_8021q.c
@@ -0,0 +1,507 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019, Vladimir Oltean <olteanv@gmail.com>
+ *
+ * This module is not a complete tagger implementation. It only provides
+ * primitives for taggers that rely on 802.1Q VLAN tags to use.
+ */
+#include <linux/if_vlan.h>
+#include <linux/dsa/8021q.h>
+
+#include "dsa_priv.h"
+
+/* Binary structure of the fake 12-bit VID field (when the TPID is
+ * ETH_P_DSA_8021Q):
+ *
+ * | 11  | 10  |  9  |  8  |  7  |  6  |  5  |  4  |  3  |  2  |  1  |  0  |
+ * +-----------+-----+-----------------+-----------+-----------------------+
+ * |    RSV    | VBID|    SWITCH_ID    |   VBID    |          PORT         |
+ * +-----------+-----+-----------------+-----------+-----------------------+
+ *
+ * RSV - VID[11:10]:
+ *	Reserved. Must be set to 3 (0b11).
+ *
+ * SWITCH_ID - VID[8:6]:
+ *	Index of switch within DSA tree. Must be between 0 and 7.
+ *
+ * VBID - { VID[9], VID[5:4] }:
+ *	Virtual bridge ID. If between 1 and 7, packet targets the broadcast
+ *	domain of a bridge. If transmitted as zero, packet targets a single
+ *	port.
+ *
+ * PORT - VID[3:0]:
+ *	Index of switch port. Must be between 0 and 15.
+ */
+
+#define DSA_8021Q_RSV_VAL		3
+#define DSA_8021Q_RSV_SHIFT		10
+#define DSA_8021Q_RSV_MASK		GENMASK(11, 10)
+#define DSA_8021Q_RSV			((DSA_8021Q_RSV_VAL << DSA_8021Q_RSV_SHIFT) & \
+							       DSA_8021Q_RSV_MASK)
+
+#define DSA_8021Q_SWITCH_ID_SHIFT	6
+#define DSA_8021Q_SWITCH_ID_MASK	GENMASK(8, 6)
+#define DSA_8021Q_SWITCH_ID(x)		(((x) << DSA_8021Q_SWITCH_ID_SHIFT) & \
+						 DSA_8021Q_SWITCH_ID_MASK)
+
+#define DSA_8021Q_VBID_HI_SHIFT		9
+#define DSA_8021Q_VBID_HI_MASK		GENMASK(9, 9)
+#define DSA_8021Q_VBID_LO_SHIFT		4
+#define DSA_8021Q_VBID_LO_MASK		GENMASK(5, 4)
+#define DSA_8021Q_VBID_HI(x)		(((x) & GENMASK(2, 2)) >> 2)
+#define DSA_8021Q_VBID_LO(x)		((x) & GENMASK(1, 0))
+#define DSA_8021Q_VBID(x)		\
+		(((DSA_8021Q_VBID_LO(x) << DSA_8021Q_VBID_LO_SHIFT) & \
+		  DSA_8021Q_VBID_LO_MASK) | \
+		 ((DSA_8021Q_VBID_HI(x) << DSA_8021Q_VBID_HI_SHIFT) & \
+		  DSA_8021Q_VBID_HI_MASK))
+
+#define DSA_8021Q_PORT_SHIFT		0
+#define DSA_8021Q_PORT_MASK		GENMASK(3, 0)
+#define DSA_8021Q_PORT(x)		(((x) << DSA_8021Q_PORT_SHIFT) & \
+						 DSA_8021Q_PORT_MASK)
+
+u16 dsa_tag_8021q_bridge_vid(unsigned int bridge_num)
+{
+	/* The VBID value of 0 is reserved for precise TX, but it is also
+	 * reserved/invalid for the bridge_num, so all is well.
+	 */
+	return DSA_8021Q_RSV | DSA_8021Q_VBID(bridge_num);
+}
+EXPORT_SYMBOL_GPL(dsa_tag_8021q_bridge_vid);
+
+/* Returns the VID that will be installed as pvid for this switch port, sent as
+ * tagged egress towards the CPU port and decoded by the rcv function.
+ */
+u16 dsa_tag_8021q_standalone_vid(const struct dsa_port *dp)
+{
+	return DSA_8021Q_RSV | DSA_8021Q_SWITCH_ID(dp->ds->index) |
+	       DSA_8021Q_PORT(dp->index);
+}
+EXPORT_SYMBOL_GPL(dsa_tag_8021q_standalone_vid);
+
+/* Returns the decoded switch ID from the RX VID. */
+int dsa_8021q_rx_switch_id(u16 vid)
+{
+	return (vid & DSA_8021Q_SWITCH_ID_MASK) >> DSA_8021Q_SWITCH_ID_SHIFT;
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_rx_switch_id);
+
+/* Returns the decoded port ID from the RX VID. */
+int dsa_8021q_rx_source_port(u16 vid)
+{
+	return (vid & DSA_8021Q_PORT_MASK) >> DSA_8021Q_PORT_SHIFT;
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_rx_source_port);
+
+/* Returns the decoded VBID from the RX VID. */
+static int dsa_tag_8021q_rx_vbid(u16 vid)
+{
+	u16 vbid_hi = (vid & DSA_8021Q_VBID_HI_MASK) >> DSA_8021Q_VBID_HI_SHIFT;
+	u16 vbid_lo = (vid & DSA_8021Q_VBID_LO_MASK) >> DSA_8021Q_VBID_LO_SHIFT;
+
+	return (vbid_hi << 2) | vbid_lo;
+}
+
+bool vid_is_dsa_8021q(u16 vid)
+{
+	u16 rsv = (vid & DSA_8021Q_RSV_MASK) >> DSA_8021Q_RSV_SHIFT;
+
+	return rsv == DSA_8021Q_RSV_VAL;
+}
+EXPORT_SYMBOL_GPL(vid_is_dsa_8021q);
+
+static struct dsa_tag_8021q_vlan *
+dsa_tag_8021q_vlan_find(struct dsa_8021q_context *ctx, int port, u16 vid)
+{
+	struct dsa_tag_8021q_vlan *v;
+
+	list_for_each_entry(v, &ctx->vlans, list)
+		if (v->vid == vid && v->port == port)
+			return v;
+
+	return NULL;
+}
+
+static int dsa_port_do_tag_8021q_vlan_add(struct dsa_port *dp, u16 vid,
+					  u16 flags)
+{
+	struct dsa_8021q_context *ctx = dp->ds->tag_8021q_ctx;
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_tag_8021q_vlan *v;
+	int port = dp->index;
+	int err;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
+		return ds->ops->tag_8021q_vlan_add(ds, port, vid, flags);
+
+	v = dsa_tag_8021q_vlan_find(ctx, port, vid);
+	if (v) {
+		refcount_inc(&v->refcount);
+		return 0;
+	}
+
+	v = kzalloc(sizeof(*v), GFP_KERNEL);
+	if (!v)
+		return -ENOMEM;
+
+	err = ds->ops->tag_8021q_vlan_add(ds, port, vid, flags);
+	if (err) {
+		kfree(v);
+		return err;
+	}
+
+	v->vid = vid;
+	v->port = port;
+	refcount_set(&v->refcount, 1);
+	list_add_tail(&v->list, &ctx->vlans);
+
+	return 0;
+}
+
+static int dsa_port_do_tag_8021q_vlan_del(struct dsa_port *dp, u16 vid)
+{
+	struct dsa_8021q_context *ctx = dp->ds->tag_8021q_ctx;
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_tag_8021q_vlan *v;
+	int port = dp->index;
+	int err;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
+		return ds->ops->tag_8021q_vlan_del(ds, port, vid);
+
+	v = dsa_tag_8021q_vlan_find(ctx, port, vid);
+	if (!v)
+		return -ENOENT;
+
+	if (!refcount_dec_and_test(&v->refcount))
+		return 0;
+
+	err = ds->ops->tag_8021q_vlan_del(ds, port, vid);
+	if (err) {
+		refcount_inc(&v->refcount);
+		return err;
+	}
+
+	list_del(&v->list);
+	kfree(v);
+
+	return 0;
+}
+
+static bool
+dsa_port_tag_8021q_vlan_match(struct dsa_port *dp,
+			      struct dsa_notifier_tag_8021q_vlan_info *info)
+{
+	return dsa_port_is_dsa(dp) || dsa_port_is_cpu(dp) || dp == info->dp;
+}
+
+int dsa_switch_tag_8021q_vlan_add(struct dsa_switch *ds,
+				  struct dsa_notifier_tag_8021q_vlan_info *info)
+{
+	struct dsa_port *dp;
+	int err;
+
+	/* Since we use dsa_broadcast(), there might be other switches in other
+	 * trees which don't support tag_8021q, so don't return an error.
+	 * Or they might even support tag_8021q but have not registered yet to
+	 * use it (maybe they use another tagger currently).
+	 */
+	if (!ds->ops->tag_8021q_vlan_add || !ds->tag_8021q_ctx)
+		return 0;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_tag_8021q_vlan_match(dp, info)) {
+			u16 flags = 0;
+
+			if (dsa_port_is_user(dp))
+				flags |= BRIDGE_VLAN_INFO_UNTAGGED |
+					 BRIDGE_VLAN_INFO_PVID;
+
+			err = dsa_port_do_tag_8021q_vlan_add(dp, info->vid,
+							     flags);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+int dsa_switch_tag_8021q_vlan_del(struct dsa_switch *ds,
+				  struct dsa_notifier_tag_8021q_vlan_info *info)
+{
+	struct dsa_port *dp;
+	int err;
+
+	if (!ds->ops->tag_8021q_vlan_del || !ds->tag_8021q_ctx)
+		return 0;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_tag_8021q_vlan_match(dp, info)) {
+			err = dsa_port_do_tag_8021q_vlan_del(dp, info->vid);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+/* There are 2 ways of offloading tag_8021q VLANs.
+ *
+ * One is to use a hardware TCAM to push the port's standalone VLAN into the
+ * frame when forwarding it to the CPU, as an egress modification rule on the
+ * CPU port. This is preferable because it has no side effects for the
+ * autonomous forwarding path, and accomplishes tag_8021q's primary goal of
+ * identifying the source port of each packet based on VLAN ID.
+ *
+ * The other is to commit the tag_8021q VLAN as a PVID to the VLAN table, and
+ * to configure the port as VLAN-unaware. This is less preferable because
+ * unique source port identification can only be done for standalone ports;
+ * under a VLAN-unaware bridge, all ports share the same tag_8021q VLAN as
+ * PVID, and under a VLAN-aware bridge, packets received by software will not
+ * have tag_8021q VLANs appended, just bridge VLANs.
+ *
+ * For tag_8021q implementations of the second type, this method is used to
+ * replace the standalone tag_8021q VLAN of a port with the tag_8021q VLAN to
+ * be used for VLAN-unaware bridging.
+ */
+int dsa_tag_8021q_bridge_join(struct dsa_switch *ds, int port,
+			      struct dsa_bridge bridge)
+{
+	struct dsa_port *dp = dsa_to_port(ds, port);
+	u16 standalone_vid, bridge_vid;
+	int err;
+
+	/* Delete the standalone VLAN of the port and replace it with a
+	 * bridging VLAN
+	 */
+	standalone_vid = dsa_tag_8021q_standalone_vid(dp);
+	bridge_vid = dsa_tag_8021q_bridge_vid(bridge.num);
+
+	err = dsa_port_tag_8021q_vlan_add(dp, bridge_vid, true);
+	if (err)
+		return err;
+
+	dsa_port_tag_8021q_vlan_del(dp, standalone_vid, false);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dsa_tag_8021q_bridge_join);
+
+void dsa_tag_8021q_bridge_leave(struct dsa_switch *ds, int port,
+				struct dsa_bridge bridge)
+{
+	struct dsa_port *dp = dsa_to_port(ds, port);
+	u16 standalone_vid, bridge_vid;
+	int err;
+
+	/* Delete the bridging VLAN of the port and replace it with a
+	 * standalone VLAN
+	 */
+	standalone_vid = dsa_tag_8021q_standalone_vid(dp);
+	bridge_vid = dsa_tag_8021q_bridge_vid(bridge.num);
+
+	err = dsa_port_tag_8021q_vlan_add(dp, standalone_vid, false);
+	if (err) {
+		dev_err(ds->dev,
+			"Failed to delete tag_8021q standalone VLAN %d from port %d: %pe\n",
+			standalone_vid, port, ERR_PTR(err));
+	}
+
+	dsa_port_tag_8021q_vlan_del(dp, bridge_vid, true);
+}
+EXPORT_SYMBOL_GPL(dsa_tag_8021q_bridge_leave);
+
+/* Set up a port's standalone tag_8021q VLAN */
+static int dsa_tag_8021q_port_setup(struct dsa_switch *ds, int port)
+{
+	struct dsa_8021q_context *ctx = ds->tag_8021q_ctx;
+	struct dsa_port *dp = dsa_to_port(ds, port);
+	u16 vid = dsa_tag_8021q_standalone_vid(dp);
+	struct net_device *master;
+	int err;
+
+	/* The CPU port is implicitly configured by
+	 * configuring the front-panel ports
+	 */
+	if (!dsa_port_is_user(dp))
+		return 0;
+
+	master = dsa_port_to_master(dp);
+
+	err = dsa_port_tag_8021q_vlan_add(dp, vid, false);
+	if (err) {
+		dev_err(ds->dev,
+			"Failed to apply standalone VID %d to port %d: %pe\n",
+			vid, port, ERR_PTR(err));
+		return err;
+	}
+
+	/* Add the VLAN to the master's RX filter. */
+	vlan_vid_add(master, ctx->proto, vid);
+
+	return err;
+}
+
+static void dsa_tag_8021q_port_teardown(struct dsa_switch *ds, int port)
+{
+	struct dsa_8021q_context *ctx = ds->tag_8021q_ctx;
+	struct dsa_port *dp = dsa_to_port(ds, port);
+	u16 vid = dsa_tag_8021q_standalone_vid(dp);
+	struct net_device *master;
+
+	/* The CPU port is implicitly configured by
+	 * configuring the front-panel ports
+	 */
+	if (!dsa_port_is_user(dp))
+		return;
+
+	master = dsa_port_to_master(dp);
+
+	dsa_port_tag_8021q_vlan_del(dp, vid, false);
+
+	vlan_vid_del(master, ctx->proto, vid);
+}
+
+static int dsa_tag_8021q_setup(struct dsa_switch *ds)
+{
+	int err, port;
+
+	ASSERT_RTNL();
+
+	for (port = 0; port < ds->num_ports; port++) {
+		err = dsa_tag_8021q_port_setup(ds, port);
+		if (err < 0) {
+			dev_err(ds->dev,
+				"Failed to setup VLAN tagging for port %d: %pe\n",
+				port, ERR_PTR(err));
+			return err;
+		}
+	}
+
+	return 0;
+}
+
+static void dsa_tag_8021q_teardown(struct dsa_switch *ds)
+{
+	int port;
+
+	ASSERT_RTNL();
+
+	for (port = 0; port < ds->num_ports; port++)
+		dsa_tag_8021q_port_teardown(ds, port);
+}
+
+int dsa_tag_8021q_register(struct dsa_switch *ds, __be16 proto)
+{
+	struct dsa_8021q_context *ctx;
+	int err;
+
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->proto = proto;
+	ctx->ds = ds;
+
+	INIT_LIST_HEAD(&ctx->vlans);
+
+	ds->tag_8021q_ctx = ctx;
+
+	err = dsa_tag_8021q_setup(ds);
+	if (err)
+		goto err_free;
+
+	return 0;
+
+err_free:
+	kfree(ctx);
+	return err;
+}
+EXPORT_SYMBOL_GPL(dsa_tag_8021q_register);
+
+void dsa_tag_8021q_unregister(struct dsa_switch *ds)
+{
+	struct dsa_8021q_context *ctx = ds->tag_8021q_ctx;
+	struct dsa_tag_8021q_vlan *v, *n;
+
+	dsa_tag_8021q_teardown(ds);
+
+	list_for_each_entry_safe(v, n, &ctx->vlans, list) {
+		list_del(&v->list);
+		kfree(v);
+	}
+
+	ds->tag_8021q_ctx = NULL;
+
+	kfree(ctx);
+}
+EXPORT_SYMBOL_GPL(dsa_tag_8021q_unregister);
+
+struct sk_buff *dsa_8021q_xmit(struct sk_buff *skb, struct net_device *netdev,
+			       u16 tpid, u16 tci)
+{
+	/* skb->data points at skb_mac_header, which
+	 * is fine for vlan_insert_tag.
+	 */
+	return vlan_insert_tag(skb, htons(tpid), tci);
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_xmit);
+
+struct net_device *dsa_tag_8021q_find_port_by_vbid(struct net_device *master,
+						   int vbid)
+{
+	struct dsa_port *cpu_dp = master->dsa_ptr;
+	struct dsa_switch_tree *dst = cpu_dp->dst;
+	struct dsa_port *dp;
+
+	if (WARN_ON(!vbid))
+		return NULL;
+
+	dsa_tree_for_each_user_port(dp, dst) {
+		if (!dp->bridge)
+			continue;
+
+		if (dp->stp_state != BR_STATE_LEARNING &&
+		    dp->stp_state != BR_STATE_FORWARDING)
+			continue;
+
+		if (dp->cpu_dp != cpu_dp)
+			continue;
+
+		if (dsa_port_bridge_num_get(dp) == vbid)
+			return dp->slave;
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(dsa_tag_8021q_find_port_by_vbid);
+
+void dsa_8021q_rcv(struct sk_buff *skb, int *source_port, int *switch_id,
+		   int *vbid)
+{
+	u16 vid, tci;
+
+	if (skb_vlan_tag_present(skb)) {
+		tci = skb_vlan_tag_get(skb);
+		__vlan_hwaccel_clear_tag(skb);
+	} else {
+		skb_push_rcsum(skb, ETH_HLEN);
+		__skb_vlan_pop(skb, &tci);
+		skb_pull_rcsum(skb, ETH_HLEN);
+	}
+
+	vid = tci & VLAN_VID_MASK;
+
+	*source_port = dsa_8021q_rx_source_port(vid);
+	*switch_id = dsa_8021q_rx_switch_id(vid);
+
+	if (vbid)
+		*vbid = dsa_tag_8021q_rx_vbid(vid);
+
+	skb->priority = (tci & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_rcv);
diff --git a/net/dsa/tag_ar9331.c b/net/dsa/tag_ar9331.c
new file mode 100644
index 000000000..8a02ac442
--- /dev/null
+++ b/net/dsa/tag_ar9331.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Pengutronix, Oleksij Rempel <kernel@pengutronix.de>
+ */
+
+
+#include <linux/bitfield.h>
+#include <linux/etherdevice.h>
+
+#include "dsa_priv.h"
+
+#define AR9331_HDR_LEN			2
+#define AR9331_HDR_VERSION		1
+
+#define AR9331_HDR_VERSION_MASK		GENMASK(15, 14)
+#define AR9331_HDR_PRIORITY_MASK	GENMASK(13, 12)
+#define AR9331_HDR_TYPE_MASK		GENMASK(10, 8)
+#define AR9331_HDR_BROADCAST		BIT(7)
+#define AR9331_HDR_FROM_CPU		BIT(6)
+/* AR9331_HDR_RESERVED - not used or may be version field.
+ * According to the AR8216 doc it should 0b10. On AR9331 it is 0b11 on RX path
+ * and should be set to 0b11 to make it work.
+ */
+#define AR9331_HDR_RESERVED_MASK	GENMASK(5, 4)
+#define AR9331_HDR_PORT_NUM_MASK	GENMASK(3, 0)
+
+static struct sk_buff *ar9331_tag_xmit(struct sk_buff *skb,
+				       struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	__le16 *phdr;
+	u16 hdr;
+
+	phdr = skb_push(skb, AR9331_HDR_LEN);
+
+	hdr = FIELD_PREP(AR9331_HDR_VERSION_MASK, AR9331_HDR_VERSION);
+	hdr |= AR9331_HDR_FROM_CPU | dp->index;
+	/* 0b10 for AR8216 and 0b11 for AR9331 */
+	hdr |= AR9331_HDR_RESERVED_MASK;
+
+	phdr[0] = cpu_to_le16(hdr);
+
+	return skb;
+}
+
+static struct sk_buff *ar9331_tag_rcv(struct sk_buff *skb,
+				      struct net_device *ndev)
+{
+	u8 ver, port;
+	u16 hdr;
+
+	if (unlikely(!pskb_may_pull(skb, AR9331_HDR_LEN)))
+		return NULL;
+
+	hdr = le16_to_cpu(*(__le16 *)skb_mac_header(skb));
+
+	ver = FIELD_GET(AR9331_HDR_VERSION_MASK, hdr);
+	if (unlikely(ver != AR9331_HDR_VERSION)) {
+		netdev_warn_once(ndev, "%s:%i wrong header version 0x%2x\n",
+				 __func__, __LINE__, hdr);
+		return NULL;
+	}
+
+	if (unlikely(hdr & AR9331_HDR_FROM_CPU)) {
+		netdev_warn_once(ndev, "%s:%i packet should not be from cpu 0x%2x\n",
+				 __func__, __LINE__, hdr);
+		return NULL;
+	}
+
+	skb_pull_rcsum(skb, AR9331_HDR_LEN);
+
+	/* Get source port information */
+	port = FIELD_GET(AR9331_HDR_PORT_NUM_MASK, hdr);
+
+	skb->dev = dsa_master_find_slave(ndev, 0, port);
+	if (!skb->dev)
+		return NULL;
+
+	return skb;
+}
+
+static const struct dsa_device_ops ar9331_netdev_ops = {
+	.name	= "ar9331",
+	.proto	= DSA_TAG_PROTO_AR9331,
+	.xmit	= ar9331_tag_xmit,
+	.rcv	= ar9331_tag_rcv,
+	.needed_headroom = AR9331_HDR_LEN,
+};
+
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_AR9331);
+module_dsa_tag_driver(ar9331_netdev_ops);
diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
new file mode 100644
index 000000000..a65d62fb9
--- /dev/null
+++ b/net/dsa/tag_brcm.c
@@ -0,0 +1,334 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Broadcom tag support
+ *
+ * Copyright (C) 2014 Broadcom Corporation
+ */
+
+#include <linux/dsa/brcm.h>
+#include <linux/etherdevice.h>
+#include <linux/if_vlan.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "dsa_priv.h"
+
+/* Legacy Broadcom tag (6 bytes) */
+#define BRCM_LEG_TAG_LEN	6
+
+/* Type fields */
+/* 1st byte in the tag */
+#define BRCM_LEG_TYPE_HI	0x88
+/* 2nd byte in the tag */
+#define BRCM_LEG_TYPE_LO	0x74
+
+/* Tag fields */
+/* 3rd byte in the tag */
+#define BRCM_LEG_UNICAST	(0 << 5)
+#define BRCM_LEG_MULTICAST	(1 << 5)
+#define BRCM_LEG_EGRESS		(2 << 5)
+#define BRCM_LEG_INGRESS	(3 << 5)
+
+/* 6th byte in the tag */
+#define BRCM_LEG_PORT_ID	(0xf)
+
+/* Newer Broadcom tag (4 bytes) */
+#define BRCM_TAG_LEN	4
+
+/* Tag is constructed and deconstructed using byte by byte access
+ * because the tag is placed after the MAC Source Address, which does
+ * not make it 4-bytes aligned, so this might cause unaligned accesses
+ * on most systems where this is used.
+ */
+
+/* Ingress and egress opcodes */
+#define BRCM_OPCODE_SHIFT	5
+#define BRCM_OPCODE_MASK	0x7
+
+/* Ingress fields */
+/* 1st byte in the tag */
+#define BRCM_IG_TC_SHIFT	2
+#define BRCM_IG_TC_MASK		0x7
+/* 2nd byte in the tag */
+#define BRCM_IG_TE_MASK		0x3
+#define BRCM_IG_TS_SHIFT	7
+/* 3rd byte in the tag */
+#define BRCM_IG_DSTMAP2_MASK	1
+#define BRCM_IG_DSTMAP1_MASK	0xff
+
+/* Egress fields */
+
+/* 2nd byte in the tag */
+#define BRCM_EG_CID_MASK	0xff
+
+/* 3rd byte in the tag */
+#define BRCM_EG_RC_MASK		0xff
+#define  BRCM_EG_RC_RSVD	(3 << 6)
+#define  BRCM_EG_RC_EXCEPTION	(1 << 5)
+#define  BRCM_EG_RC_PROT_SNOOP	(1 << 4)
+#define  BRCM_EG_RC_PROT_TERM	(1 << 3)
+#define  BRCM_EG_RC_SWITCH	(1 << 2)
+#define  BRCM_EG_RC_MAC_LEARN	(1 << 1)
+#define  BRCM_EG_RC_MIRROR	(1 << 0)
+#define BRCM_EG_TC_SHIFT	5
+#define BRCM_EG_TC_MASK		0x7
+#define BRCM_EG_PID_MASK	0x1f
+
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM) || \
+	IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
+
+static struct sk_buff *brcm_tag_xmit_ll(struct sk_buff *skb,
+					struct net_device *dev,
+					unsigned int offset)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u16 queue = skb_get_queue_mapping(skb);
+	u8 *brcm_tag;
+
+	/* The Ethernet switch we are interfaced with needs packets to be at
+	 * least 64 bytes (including FCS) otherwise they will be discarded when
+	 * they enter the switch port logic. When Broadcom tags are enabled, we
+	 * need to make sure that packets are at least 68 bytes
+	 * (including FCS and tag) because the length verification is done after
+	 * the Broadcom tag is stripped off the ingress packet.
+	 *
+	 * Let dsa_slave_xmit() free the SKB
+	 */
+	if (__skb_put_padto(skb, ETH_ZLEN + BRCM_TAG_LEN, false))
+		return NULL;
+
+	skb_push(skb, BRCM_TAG_LEN);
+
+	if (offset)
+		dsa_alloc_etype_header(skb, BRCM_TAG_LEN);
+
+	brcm_tag = skb->data + offset;
+
+	/* Set the ingress opcode, traffic class, tag enforcement is
+	 * deprecated
+	 */
+	brcm_tag[0] = (1 << BRCM_OPCODE_SHIFT) |
+		       ((queue & BRCM_IG_TC_MASK) << BRCM_IG_TC_SHIFT);
+	brcm_tag[1] = 0;
+	brcm_tag[2] = 0;
+	if (dp->index == 8)
+		brcm_tag[2] = BRCM_IG_DSTMAP2_MASK;
+	brcm_tag[3] = (1 << dp->index) & BRCM_IG_DSTMAP1_MASK;
+
+	/* Now tell the master network device about the desired output queue
+	 * as well
+	 */
+	skb_set_queue_mapping(skb, BRCM_TAG_SET_PORT_QUEUE(dp->index, queue));
+
+	return skb;
+}
+
+/* Frames with this tag have one of these two layouts:
+ * -----------------------------------
+ * | MAC DA | MAC SA | 4b tag | Type | DSA_TAG_PROTO_BRCM
+ * -----------------------------------
+ * -----------------------------------
+ * | 4b tag | MAC DA | MAC SA | Type | DSA_TAG_PROTO_BRCM_PREPEND
+ * -----------------------------------
+ * In both cases, at receive time, skb->data points 2 bytes before the actual
+ * Ethernet type field and we have an offset of 4bytes between where skb->data
+ * and where the payload starts. So the same low-level receive function can be
+ * used.
+ */
+static struct sk_buff *brcm_tag_rcv_ll(struct sk_buff *skb,
+				       struct net_device *dev,
+				       unsigned int offset)
+{
+	int source_port;
+	u8 *brcm_tag;
+
+	if (unlikely(!pskb_may_pull(skb, BRCM_TAG_LEN)))
+		return NULL;
+
+	brcm_tag = skb->data - offset;
+
+	/* The opcode should never be different than 0b000 */
+	if (unlikely((brcm_tag[0] >> BRCM_OPCODE_SHIFT) & BRCM_OPCODE_MASK))
+		return NULL;
+
+	/* We should never see a reserved reason code without knowing how to
+	 * handle it
+	 */
+	if (unlikely(brcm_tag[2] & BRCM_EG_RC_RSVD))
+		return NULL;
+
+	/* Locate which port this is coming from */
+	source_port = brcm_tag[3] & BRCM_EG_PID_MASK;
+
+	skb->dev = dsa_master_find_slave(dev, 0, source_port);
+	if (!skb->dev)
+		return NULL;
+
+	/* Remove Broadcom tag and update checksum */
+	skb_pull_rcsum(skb, BRCM_TAG_LEN);
+
+	dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+#endif
+
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM)
+static struct sk_buff *brcm_tag_xmit(struct sk_buff *skb,
+				     struct net_device *dev)
+{
+	/* Build the tag after the MAC Source Address */
+	return brcm_tag_xmit_ll(skb, dev, 2 * ETH_ALEN);
+}
+
+
+static struct sk_buff *brcm_tag_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	struct sk_buff *nskb;
+
+	/* skb->data points to the EtherType, the tag is right before it */
+	nskb = brcm_tag_rcv_ll(skb, dev, 2);
+	if (!nskb)
+		return nskb;
+
+	dsa_strip_etype_header(skb, BRCM_TAG_LEN);
+
+	return nskb;
+}
+
+static const struct dsa_device_ops brcm_netdev_ops = {
+	.name	= "brcm",
+	.proto	= DSA_TAG_PROTO_BRCM,
+	.xmit	= brcm_tag_xmit,
+	.rcv	= brcm_tag_rcv,
+	.needed_headroom = BRCM_TAG_LEN,
+};
+
+DSA_TAG_DRIVER(brcm_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM);
+#endif
+
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
+static struct sk_buff *brcm_leg_tag_xmit(struct sk_buff *skb,
+					 struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u8 *brcm_tag;
+
+	/* The Ethernet switch we are interfaced with needs packets to be at
+	 * least 64 bytes (including FCS) otherwise they will be discarded when
+	 * they enter the switch port logic. When Broadcom tags are enabled, we
+	 * need to make sure that packets are at least 70 bytes
+	 * (including FCS and tag) because the length verification is done after
+	 * the Broadcom tag is stripped off the ingress packet.
+	 *
+	 * Let dsa_slave_xmit() free the SKB
+	 */
+	if (__skb_put_padto(skb, ETH_ZLEN + BRCM_LEG_TAG_LEN, false))
+		return NULL;
+
+	skb_push(skb, BRCM_LEG_TAG_LEN);
+
+	dsa_alloc_etype_header(skb, BRCM_LEG_TAG_LEN);
+
+	brcm_tag = skb->data + 2 * ETH_ALEN;
+
+	/* Broadcom tag type */
+	brcm_tag[0] = BRCM_LEG_TYPE_HI;
+	brcm_tag[1] = BRCM_LEG_TYPE_LO;
+
+	/* Broadcom tag value */
+	brcm_tag[2] = BRCM_LEG_EGRESS;
+	brcm_tag[3] = 0;
+	brcm_tag[4] = 0;
+	brcm_tag[5] = dp->index & BRCM_LEG_PORT_ID;
+
+	return skb;
+}
+
+static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
+					struct net_device *dev)
+{
+	int len = BRCM_LEG_TAG_LEN;
+	int source_port;
+	u8 *brcm_tag;
+
+	if (unlikely(!pskb_may_pull(skb, BRCM_LEG_PORT_ID)))
+		return NULL;
+
+	brcm_tag = dsa_etype_header_pos_rx(skb);
+
+	source_port = brcm_tag[5] & BRCM_LEG_PORT_ID;
+
+	skb->dev = dsa_master_find_slave(dev, 0, source_port);
+	if (!skb->dev)
+		return NULL;
+
+	/* VLAN tag is added by BCM63xx internal switch */
+	if (netdev_uses_dsa(skb->dev))
+		len += VLAN_HLEN;
+
+	/* Remove Broadcom tag and update checksum */
+	skb_pull_rcsum(skb, len);
+
+	dsa_default_offload_fwd_mark(skb);
+
+	dsa_strip_etype_header(skb, len);
+
+	return skb;
+}
+
+static const struct dsa_device_ops brcm_legacy_netdev_ops = {
+	.name = "brcm-legacy",
+	.proto = DSA_TAG_PROTO_BRCM_LEGACY,
+	.xmit = brcm_leg_tag_xmit,
+	.rcv = brcm_leg_tag_rcv,
+	.needed_headroom = BRCM_LEG_TAG_LEN,
+};
+
+DSA_TAG_DRIVER(brcm_legacy_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_LEGACY);
+#endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY */
+
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
+static struct sk_buff *brcm_tag_xmit_prepend(struct sk_buff *skb,
+					     struct net_device *dev)
+{
+	/* tag is prepended to the packet */
+	return brcm_tag_xmit_ll(skb, dev, 0);
+}
+
+static struct sk_buff *brcm_tag_rcv_prepend(struct sk_buff *skb,
+					    struct net_device *dev)
+{
+	/* tag is prepended to the packet */
+	return brcm_tag_rcv_ll(skb, dev, ETH_HLEN);
+}
+
+static const struct dsa_device_ops brcm_prepend_netdev_ops = {
+	.name	= "brcm-prepend",
+	.proto	= DSA_TAG_PROTO_BRCM_PREPEND,
+	.xmit	= brcm_tag_xmit_prepend,
+	.rcv	= brcm_tag_rcv_prepend,
+	.needed_headroom = BRCM_TAG_LEN,
+};
+
+DSA_TAG_DRIVER(brcm_prepend_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_PREPEND);
+#endif
+
+static struct dsa_tag_driver *dsa_tag_driver_array[] =	{
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM)
+	&DSA_TAG_DRIVER_NAME(brcm_netdev_ops),
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
+	&DSA_TAG_DRIVER_NAME(brcm_legacy_netdev_ops),
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
+	&DSA_TAG_DRIVER_NAME(brcm_prepend_netdev_ops),
+#endif
+};
+
+module_dsa_tag_drivers(dsa_tag_driver_array);
+
+MODULE_LICENSE("GPL");
diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c
new file mode 100644
index 000000000..e4b6e3f2a
--- /dev/null
+++ b/net/dsa/tag_dsa.c
@@ -0,0 +1,406 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Regular and Ethertype DSA tagging
+ * Copyright (c) 2008-2009 Marvell Semiconductor
+ *
+ * Regular DSA
+ * -----------
+
+ * For untagged (in 802.1Q terms) packets, the switch will splice in
+ * the tag between the SA and the ethertype of the original
+ * packet. Tagged frames will instead have their outermost .1Q tag
+ * converted to a DSA tag. It expects the same layout when receiving
+ * packets from the CPU.
+ *
+ * Example:
+ *
+ *     .----.----.----.---------
+ * Pu: | DA | SA | ET | Payload ...
+ *     '----'----'----'---------
+ *       6    6    2       N
+ *     .----.----.--------.-----.----.---------
+ * Pt: | DA | SA | 0x8100 | TCI | ET | Payload ...
+ *     '----'----'--------'-----'----'---------
+ *       6    6       2      2    2       N
+ *     .----.----.-----.----.---------
+ * Pd: | DA | SA | DSA | ET | Payload ...
+ *     '----'----'-----'----'---------
+ *       6    6     4    2       N
+ *
+ * No matter if a packet is received untagged (Pu) or tagged (Pt),
+ * they will both have the same layout (Pd) when they are sent to the
+ * CPU. This is done by ignoring 802.3, replacing the ethertype field
+ * with more metadata, among which is a bit to signal if the original
+ * packet was tagged or not.
+ *
+ * Ethertype DSA
+ * -------------
+ * Uses the exact same tag format as regular DSA, but also includes a
+ * proper ethertype field (which the mv88e6xxx driver sets to
+ * ETH_P_EDSA/0xdada) followed by two zero bytes:
+ *
+ * .----.----.--------.--------.-----.----.---------
+ * | DA | SA | 0xdada | 0x0000 | DSA | ET | Payload ...
+ * '----'----'--------'--------'-----'----'---------
+ *   6    6       2        2      4    2       N
+ */
+
+#include <linux/dsa/mv88e6xxx.h>
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "dsa_priv.h"
+
+#define DSA_HLEN	4
+
+/**
+ * enum dsa_cmd - DSA Command
+ * @DSA_CMD_TO_CPU: Set on packets that were trapped or mirrored to
+ *     the CPU port. This is needed to implement control protocols,
+ *     e.g. STP and LLDP, that must not allow those control packets to
+ *     be switched according to the normal rules.
+ * @DSA_CMD_FROM_CPU: Used by the CPU to send a packet to a specific
+ *     port, ignoring all the barriers that the switch normally
+ *     enforces (VLANs, STP port states etc.). No source address
+ *     learning takes place. "sudo send packet"
+ * @DSA_CMD_TO_SNIFFER: Set on the copies of packets that matched some
+ *     user configured ingress or egress monitor criteria. These are
+ *     forwarded by the switch tree to the user configured ingress or
+ *     egress monitor port, which can be set to the CPU port or a
+ *     regular port. If the destination is a regular port, the tag
+ *     will be removed before egressing the port. If the destination
+ *     is the CPU port, the tag will not be removed.
+ * @DSA_CMD_FORWARD: This tag is used on all bulk traffic passing
+ *     through the switch tree, including the flows that are directed
+ *     towards the CPU. Its device/port tuple encodes the original
+ *     source port on which the packet ingressed. It can also be used
+ *     on transmit by the CPU to defer the forwarding decision to the
+ *     hardware, based on the current config of PVT/VTU/ATU
+ *     etc. Source address learning takes places if enabled on the
+ *     receiving DSA/CPU port.
+ */
+enum dsa_cmd {
+	DSA_CMD_TO_CPU     = 0,
+	DSA_CMD_FROM_CPU   = 1,
+	DSA_CMD_TO_SNIFFER = 2,
+	DSA_CMD_FORWARD    = 3
+};
+
+/**
+ * enum dsa_code - TO_CPU Code
+ *
+ * @DSA_CODE_MGMT_TRAP: DA was classified as a management
+ *     address. Typical examples include STP BPDUs and LLDP.
+ * @DSA_CODE_FRAME2REG: Response to a "remote management" request.
+ * @DSA_CODE_IGMP_MLD_TRAP: IGMP/MLD signaling.
+ * @DSA_CODE_POLICY_TRAP: Frame matched some policy configuration on
+ *     the device. Typical examples are matching on DA/SA/VID and DHCP
+ *     snooping.
+ * @DSA_CODE_ARP_MIRROR: The name says it all really.
+ * @DSA_CODE_POLICY_MIRROR: Same as @DSA_CODE_POLICY_TRAP, but the
+ *     particular policy was set to trigger a mirror instead of a
+ *     trap.
+ * @DSA_CODE_RESERVED_6: Unused on all devices up to at least 6393X.
+ * @DSA_CODE_RESERVED_7: Unused on all devices up to at least 6393X.
+ *
+ * A 3-bit code is used to relay why a particular frame was sent to
+ * the CPU. We only use this to determine if the packet was mirrored
+ * or trapped, i.e. whether the packet has been forwarded by hardware
+ * or not.
+ *
+ * This is the superset of all possible codes. Any particular device
+ * may only implement a subset.
+ */
+enum dsa_code {
+	DSA_CODE_MGMT_TRAP     = 0,
+	DSA_CODE_FRAME2REG     = 1,
+	DSA_CODE_IGMP_MLD_TRAP = 2,
+	DSA_CODE_POLICY_TRAP   = 3,
+	DSA_CODE_ARP_MIRROR    = 4,
+	DSA_CODE_POLICY_MIRROR = 5,
+	DSA_CODE_RESERVED_6    = 6,
+	DSA_CODE_RESERVED_7    = 7
+};
+
+static struct sk_buff *dsa_xmit_ll(struct sk_buff *skb, struct net_device *dev,
+				   u8 extra)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct net_device *br_dev;
+	u8 tag_dev, tag_port;
+	enum dsa_cmd cmd;
+	u8 *dsa_header;
+
+	if (skb->offload_fwd_mark) {
+		unsigned int bridge_num = dsa_port_bridge_num_get(dp);
+		struct dsa_switch_tree *dst = dp->ds->dst;
+
+		cmd = DSA_CMD_FORWARD;
+
+		/* When offloading forwarding for a bridge, inject FORWARD
+		 * packets on behalf of a virtual switch device with an index
+		 * past the physical switches.
+		 */
+		tag_dev = dst->last_switch + bridge_num;
+		tag_port = 0;
+	} else {
+		cmd = DSA_CMD_FROM_CPU;
+		tag_dev = dp->ds->index;
+		tag_port = dp->index;
+	}
+
+	br_dev = dsa_port_bridge_dev_get(dp);
+
+	/* If frame is already 802.1Q tagged, we can convert it to a DSA
+	 * tag (avoiding a memmove), but only if the port is standalone
+	 * (in which case we always send FROM_CPU) or if the port's
+	 * bridge has VLAN filtering enabled (in which case the CPU port
+	 * will be a member of the VLAN).
+	 */
+	if (skb->protocol == htons(ETH_P_8021Q) &&
+	    (!br_dev || br_vlan_enabled(br_dev))) {
+		if (extra) {
+			skb_push(skb, extra);
+			dsa_alloc_etype_header(skb, extra);
+		}
+
+		/* Construct tagged DSA tag from 802.1Q tag. */
+		dsa_header = dsa_etype_header_pos_tx(skb) + extra;
+		dsa_header[0] = (cmd << 6) | 0x20 | tag_dev;
+		dsa_header[1] = tag_port << 3;
+
+		/* Move CFI field from byte 2 to byte 1. */
+		if (dsa_header[2] & 0x10) {
+			dsa_header[1] |= 0x01;
+			dsa_header[2] &= ~0x10;
+		}
+	} else {
+		u16 vid;
+
+		vid = br_dev ? MV88E6XXX_VID_BRIDGED : MV88E6XXX_VID_STANDALONE;
+
+		skb_push(skb, DSA_HLEN + extra);
+		dsa_alloc_etype_header(skb, DSA_HLEN + extra);
+
+		/* Construct DSA header from untagged frame. */
+		dsa_header = dsa_etype_header_pos_tx(skb) + extra;
+
+		dsa_header[0] = (cmd << 6) | tag_dev;
+		dsa_header[1] = tag_port << 3;
+		dsa_header[2] = vid >> 8;
+		dsa_header[3] = vid & 0xff;
+	}
+
+	return skb;
+}
+
+static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev,
+				  u8 extra)
+{
+	bool trap = false, trunk = false;
+	int source_device, source_port;
+	enum dsa_code code;
+	enum dsa_cmd cmd;
+	u8 *dsa_header;
+
+	/* The ethertype field is part of the DSA header. */
+	dsa_header = dsa_etype_header_pos_rx(skb);
+
+	cmd = dsa_header[0] >> 6;
+	switch (cmd) {
+	case DSA_CMD_FORWARD:
+		trunk = !!(dsa_header[1] & 4);
+		break;
+
+	case DSA_CMD_TO_CPU:
+		code = (dsa_header[1] & 0x6) | ((dsa_header[2] >> 4) & 1);
+
+		switch (code) {
+		case DSA_CODE_FRAME2REG:
+			/* Remote management is not implemented yet,
+			 * drop.
+			 */
+			return NULL;
+		case DSA_CODE_ARP_MIRROR:
+		case DSA_CODE_POLICY_MIRROR:
+			/* Mark mirrored packets to notify any upper
+			 * device (like a bridge) that forwarding has
+			 * already been done by hardware.
+			 */
+			break;
+		case DSA_CODE_MGMT_TRAP:
+		case DSA_CODE_IGMP_MLD_TRAP:
+		case DSA_CODE_POLICY_TRAP:
+			/* Traps have, by definition, not been
+			 * forwarded by hardware, so don't mark them.
+			 */
+			trap = true;
+			break;
+		default:
+			/* Reserved code, this could be anything. Drop
+			 * seems like the safest option.
+			 */
+			return NULL;
+		}
+
+		break;
+
+	default:
+		return NULL;
+	}
+
+	source_device = dsa_header[0] & 0x1f;
+	source_port = (dsa_header[1] >> 3) & 0x1f;
+
+	if (trunk) {
+		struct dsa_port *cpu_dp = dev->dsa_ptr;
+		struct dsa_lag *lag;
+
+		/* The exact source port is not available in the tag,
+		 * so we inject the frame directly on the upper
+		 * team/bond.
+		 */
+		lag = dsa_lag_by_id(cpu_dp->dst, source_port + 1);
+		skb->dev = lag ? lag->dev : NULL;
+	} else {
+		skb->dev = dsa_master_find_slave(dev, source_device,
+						 source_port);
+	}
+
+	if (!skb->dev)
+		return NULL;
+
+	/* When using LAG offload, skb->dev is not a DSA slave interface,
+	 * so we cannot call dsa_default_offload_fwd_mark and we need to
+	 * special-case it.
+	 */
+	if (trunk)
+		skb->offload_fwd_mark = true;
+	else if (!trap)
+		dsa_default_offload_fwd_mark(skb);
+
+	/* If the 'tagged' bit is set; convert the DSA tag to a 802.1Q
+	 * tag, and delete the ethertype (extra) if applicable. If the
+	 * 'tagged' bit is cleared; delete the DSA tag, and ethertype
+	 * if applicable.
+	 */
+	if (dsa_header[0] & 0x20) {
+		u8 new_header[4];
+
+		/* Insert 802.1Q ethertype and copy the VLAN-related
+		 * fields, but clear the bit that will hold CFI (since
+		 * DSA uses that bit location for another purpose).
+		 */
+		new_header[0] = (ETH_P_8021Q >> 8) & 0xff;
+		new_header[1] = ETH_P_8021Q & 0xff;
+		new_header[2] = dsa_header[2] & ~0x10;
+		new_header[3] = dsa_header[3];
+
+		/* Move CFI bit from its place in the DSA header to
+		 * its 802.1Q-designated place.
+		 */
+		if (dsa_header[1] & 0x01)
+			new_header[2] |= 0x10;
+
+		/* Update packet checksum if skb is CHECKSUM_COMPLETE. */
+		if (skb->ip_summed == CHECKSUM_COMPLETE) {
+			__wsum c = skb->csum;
+			c = csum_add(c, csum_partial(new_header + 2, 2, 0));
+			c = csum_sub(c, csum_partial(dsa_header + 2, 2, 0));
+			skb->csum = c;
+		}
+
+		memcpy(dsa_header, new_header, DSA_HLEN);
+
+		if (extra)
+			dsa_strip_etype_header(skb, extra);
+	} else {
+		skb_pull_rcsum(skb, DSA_HLEN);
+		dsa_strip_etype_header(skb, DSA_HLEN + extra);
+	}
+
+	return skb;
+}
+
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_DSA)
+
+static struct sk_buff *dsa_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	return dsa_xmit_ll(skb, dev, 0);
+}
+
+static struct sk_buff *dsa_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	if (unlikely(!pskb_may_pull(skb, DSA_HLEN)))
+		return NULL;
+
+	return dsa_rcv_ll(skb, dev, 0);
+}
+
+static const struct dsa_device_ops dsa_netdev_ops = {
+	.name	  = "dsa",
+	.proto	  = DSA_TAG_PROTO_DSA,
+	.xmit	  = dsa_xmit,
+	.rcv	  = dsa_rcv,
+	.needed_headroom = DSA_HLEN,
+};
+
+DSA_TAG_DRIVER(dsa_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_DSA);
+#endif	/* CONFIG_NET_DSA_TAG_DSA */
+
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_EDSA)
+
+#define EDSA_HLEN 8
+
+static struct sk_buff *edsa_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	u8 *edsa_header;
+
+	skb = dsa_xmit_ll(skb, dev, EDSA_HLEN - DSA_HLEN);
+	if (!skb)
+		return NULL;
+
+	edsa_header = dsa_etype_header_pos_tx(skb);
+	edsa_header[0] = (ETH_P_EDSA >> 8) & 0xff;
+	edsa_header[1] = ETH_P_EDSA & 0xff;
+	edsa_header[2] = 0x00;
+	edsa_header[3] = 0x00;
+	return skb;
+}
+
+static struct sk_buff *edsa_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	if (unlikely(!pskb_may_pull(skb, EDSA_HLEN)))
+		return NULL;
+
+	skb_pull_rcsum(skb, EDSA_HLEN - DSA_HLEN);
+
+	return dsa_rcv_ll(skb, dev, EDSA_HLEN - DSA_HLEN);
+}
+
+static const struct dsa_device_ops edsa_netdev_ops = {
+	.name	  = "edsa",
+	.proto	  = DSA_TAG_PROTO_EDSA,
+	.xmit	  = edsa_xmit,
+	.rcv	  = edsa_rcv,
+	.needed_headroom = EDSA_HLEN,
+};
+
+DSA_TAG_DRIVER(edsa_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_EDSA);
+#endif	/* CONFIG_NET_DSA_TAG_EDSA */
+
+static struct dsa_tag_driver *dsa_tag_drivers[] = {
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_DSA)
+	&DSA_TAG_DRIVER_NAME(dsa_netdev_ops),
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_EDSA)
+	&DSA_TAG_DRIVER_NAME(edsa_netdev_ops),
+#endif
+};
+
+module_dsa_tag_drivers(dsa_tag_drivers);
+
+MODULE_LICENSE("GPL");
diff --git a/net/dsa/tag_gswip.c b/net/dsa/tag_gswip.c
new file mode 100644
index 000000000..df7140984
--- /dev/null
+++ b/net/dsa/tag_gswip.c
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel / Lantiq GSWIP V2.0 PMAC tag support
+ *
+ * Copyright (C) 2017 - 2018 Hauke Mehrtens <hauke@hauke-m.de>
+ */
+
+#include <linux/bitops.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <net/dsa.h>
+
+#include "dsa_priv.h"
+
+#define GSWIP_TX_HEADER_LEN		4
+
+/* special tag in TX path header */
+/* Byte 0 */
+#define GSWIP_TX_SLPID_SHIFT		0	/* source port ID */
+#define  GSWIP_TX_SLPID_CPU		2
+#define  GSWIP_TX_SLPID_APP1		3
+#define  GSWIP_TX_SLPID_APP2		4
+#define  GSWIP_TX_SLPID_APP3		5
+#define  GSWIP_TX_SLPID_APP4		6
+#define  GSWIP_TX_SLPID_APP5		7
+
+/* Byte 1 */
+#define GSWIP_TX_CRCGEN_DIS		BIT(7)
+#define GSWIP_TX_DPID_SHIFT		0	/* destination group ID */
+#define  GSWIP_TX_DPID_ELAN		0
+#define  GSWIP_TX_DPID_EWAN		1
+#define  GSWIP_TX_DPID_CPU		2
+#define  GSWIP_TX_DPID_APP1		3
+#define  GSWIP_TX_DPID_APP2		4
+#define  GSWIP_TX_DPID_APP3		5
+#define  GSWIP_TX_DPID_APP4		6
+#define  GSWIP_TX_DPID_APP5		7
+
+/* Byte 2 */
+#define GSWIP_TX_PORT_MAP_EN		BIT(7)
+#define GSWIP_TX_PORT_MAP_SEL		BIT(6)
+#define GSWIP_TX_LRN_DIS		BIT(5)
+#define GSWIP_TX_CLASS_EN		BIT(4)
+#define GSWIP_TX_CLASS_SHIFT		0
+#define GSWIP_TX_CLASS_MASK		GENMASK(3, 0)
+
+/* Byte 3 */
+#define GSWIP_TX_DPID_EN		BIT(0)
+#define GSWIP_TX_PORT_MAP_SHIFT		1
+#define GSWIP_TX_PORT_MAP_MASK		GENMASK(6, 1)
+
+#define GSWIP_RX_HEADER_LEN	8
+
+/* special tag in RX path header */
+/* Byte 7 */
+#define GSWIP_RX_SPPID_SHIFT		4
+#define GSWIP_RX_SPPID_MASK		GENMASK(6, 4)
+
+static struct sk_buff *gswip_tag_xmit(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u8 *gswip_tag;
+
+	skb_push(skb, GSWIP_TX_HEADER_LEN);
+
+	gswip_tag = skb->data;
+	gswip_tag[0] = GSWIP_TX_SLPID_CPU;
+	gswip_tag[1] = GSWIP_TX_DPID_ELAN;
+	gswip_tag[2] = GSWIP_TX_PORT_MAP_EN | GSWIP_TX_PORT_MAP_SEL;
+	gswip_tag[3] = BIT(dp->index + GSWIP_TX_PORT_MAP_SHIFT) & GSWIP_TX_PORT_MAP_MASK;
+	gswip_tag[3] |= GSWIP_TX_DPID_EN;
+
+	return skb;
+}
+
+static struct sk_buff *gswip_tag_rcv(struct sk_buff *skb,
+				     struct net_device *dev)
+{
+	int port;
+	u8 *gswip_tag;
+
+	if (unlikely(!pskb_may_pull(skb, GSWIP_RX_HEADER_LEN)))
+		return NULL;
+
+	gswip_tag = skb->data - ETH_HLEN;
+
+	/* Get source port information */
+	port = (gswip_tag[7] & GSWIP_RX_SPPID_MASK) >> GSWIP_RX_SPPID_SHIFT;
+	skb->dev = dsa_master_find_slave(dev, 0, port);
+	if (!skb->dev)
+		return NULL;
+
+	/* remove GSWIP tag */
+	skb_pull_rcsum(skb, GSWIP_RX_HEADER_LEN);
+
+	return skb;
+}
+
+static const struct dsa_device_ops gswip_netdev_ops = {
+	.name = "gswip",
+	.proto	= DSA_TAG_PROTO_GSWIP,
+	.xmit = gswip_tag_xmit,
+	.rcv = gswip_tag_rcv,
+	.needed_headroom = GSWIP_RX_HEADER_LEN,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_GSWIP);
+
+module_dsa_tag_driver(gswip_netdev_ops);
diff --git a/net/dsa/tag_hellcreek.c b/net/dsa/tag_hellcreek.c
new file mode 100644
index 000000000..53a206d11
--- /dev/null
+++ b/net/dsa/tag_hellcreek.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * net/dsa/tag_hellcreek.c - Hirschmann Hellcreek switch tag format handling
+ *
+ * Copyright (C) 2019,2020 Linutronix GmbH
+ * Author Kurt Kanzenbach <kurt@linutronix.de>
+ *
+ * Based on tag_ksz.c.
+ */
+
+#include <linux/skbuff.h>
+#include <net/dsa.h>
+
+#include "dsa_priv.h"
+
+#define HELLCREEK_TAG_LEN	1
+
+static struct sk_buff *hellcreek_xmit(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u8 *tag;
+
+	/* Calculate checksums (if required) before adding the trailer tag to
+	 * avoid including it in calculations. That would lead to wrong
+	 * checksums after the switch strips the tag.
+	 */
+	if (skb->ip_summed == CHECKSUM_PARTIAL &&
+	    skb_checksum_help(skb))
+		return NULL;
+
+	/* Tag encoding */
+	tag  = skb_put(skb, HELLCREEK_TAG_LEN);
+	*tag = BIT(dp->index);
+
+	return skb;
+}
+
+static struct sk_buff *hellcreek_rcv(struct sk_buff *skb,
+				     struct net_device *dev)
+{
+	/* Tag decoding */
+	u8 *tag = skb_tail_pointer(skb) - HELLCREEK_TAG_LEN;
+	unsigned int port = tag[0] & 0x03;
+
+	skb->dev = dsa_master_find_slave(dev, 0, port);
+	if (!skb->dev) {
+		netdev_warn_once(dev, "Failed to get source port: %d\n", port);
+		return NULL;
+	}
+
+	if (pskb_trim_rcsum(skb, skb->len - HELLCREEK_TAG_LEN))
+		return NULL;
+
+	dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+
+static const struct dsa_device_ops hellcreek_netdev_ops = {
+	.name	  = "hellcreek",
+	.proto	  = DSA_TAG_PROTO_HELLCREEK,
+	.xmit	  = hellcreek_xmit,
+	.rcv	  = hellcreek_rcv,
+	.needed_tailroom = HELLCREEK_TAG_LEN,
+};
+
+MODULE_LICENSE("Dual MIT/GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_HELLCREEK);
+
+module_dsa_tag_driver(hellcreek_netdev_ops);
diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c
new file mode 100644
index 000000000..429250298
--- /dev/null
+++ b/net/dsa/tag_ksz.c
@@ -0,0 +1,264 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * net/dsa/tag_ksz.c - Microchip KSZ Switch tag format handling
+ * Copyright (c) 2017 Microchip Technology
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <net/dsa.h>
+#include "dsa_priv.h"
+
+/* Typically only one byte is used for tail tag. */
+#define KSZ_EGRESS_TAG_LEN		1
+#define KSZ_INGRESS_TAG_LEN		1
+
+static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,
+				      struct net_device *dev,
+				      unsigned int port, unsigned int len)
+{
+	skb->dev = dsa_master_find_slave(dev, 0, port);
+	if (!skb->dev)
+		return NULL;
+
+	if (pskb_trim_rcsum(skb, skb->len - len))
+		return NULL;
+
+	dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+
+/*
+ * For Ingress (Host -> KSZ8795), 1 byte is added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
+ *
+ * For Egress (KSZ8795 -> Host), 1 byte is added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0 : zero-based value represents port
+ *	  (eg, 0x00=port1, 0x02=port3, 0x06=port7)
+ */
+
+#define KSZ8795_TAIL_TAG_OVERRIDE	BIT(6)
+#define KSZ8795_TAIL_TAG_LOOKUP		BIT(7)
+
+static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u8 *tag;
+	u8 *addr;
+
+	if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
+		return NULL;
+
+	/* Tag encoding */
+	tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
+	addr = skb_mac_header(skb);
+
+	*tag = 1 << dp->index;
+	if (is_link_local_ether_addr(addr))
+		*tag |= KSZ8795_TAIL_TAG_OVERRIDE;
+
+	return skb;
+}
+
+static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
+
+	return ksz_common_rcv(skb, dev, tag[0] & 7, KSZ_EGRESS_TAG_LEN);
+}
+
+static const struct dsa_device_ops ksz8795_netdev_ops = {
+	.name	= "ksz8795",
+	.proto	= DSA_TAG_PROTO_KSZ8795,
+	.xmit	= ksz8795_xmit,
+	.rcv	= ksz8795_rcv,
+	.needed_tailroom = KSZ_INGRESS_TAG_LEN,
+};
+
+DSA_TAG_DRIVER(ksz8795_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795);
+
+/*
+ * For Ingress (Host -> KSZ9477), 2 bytes are added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0 : Prioritization (not used now)
+ * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
+ *
+ * For Egress (KSZ9477 -> Host), 1 byte is added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0 : zero-based value represents port
+ *	  (eg, 0x00=port1, 0x02=port3, 0x06=port7)
+ */
+
+#define KSZ9477_INGRESS_TAG_LEN		2
+#define KSZ9477_PTP_TAG_LEN		4
+#define KSZ9477_PTP_TAG_INDICATION	0x80
+
+#define KSZ9477_TAIL_TAG_OVERRIDE	BIT(9)
+#define KSZ9477_TAIL_TAG_LOOKUP		BIT(10)
+
+static struct sk_buff *ksz9477_xmit(struct sk_buff *skb,
+				    struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	__be16 *tag;
+	u8 *addr;
+	u16 val;
+
+	if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
+		return NULL;
+
+	/* Tag encoding */
+	tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN);
+	addr = skb_mac_header(skb);
+
+	val = BIT(dp->index);
+
+	if (is_link_local_ether_addr(addr))
+		val |= KSZ9477_TAIL_TAG_OVERRIDE;
+
+	*tag = cpu_to_be16(val);
+
+	return skb;
+}
+
+static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	/* Tag decoding */
+	u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
+	unsigned int port = tag[0] & 7;
+	unsigned int len = KSZ_EGRESS_TAG_LEN;
+
+	/* Extra 4-bytes PTP timestamp */
+	if (tag[0] & KSZ9477_PTP_TAG_INDICATION)
+		len += KSZ9477_PTP_TAG_LEN;
+
+	return ksz_common_rcv(skb, dev, port, len);
+}
+
+static const struct dsa_device_ops ksz9477_netdev_ops = {
+	.name	= "ksz9477",
+	.proto	= DSA_TAG_PROTO_KSZ9477,
+	.xmit	= ksz9477_xmit,
+	.rcv	= ksz9477_rcv,
+	.needed_tailroom = KSZ9477_INGRESS_TAG_LEN,
+};
+
+DSA_TAG_DRIVER(ksz9477_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477);
+
+#define KSZ9893_TAIL_TAG_OVERRIDE	BIT(5)
+#define KSZ9893_TAIL_TAG_LOOKUP		BIT(6)
+
+static struct sk_buff *ksz9893_xmit(struct sk_buff *skb,
+				    struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u8 *addr;
+	u8 *tag;
+
+	if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
+		return NULL;
+
+	/* Tag encoding */
+	tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
+	addr = skb_mac_header(skb);
+
+	*tag = BIT(dp->index);
+
+	if (is_link_local_ether_addr(addr))
+		*tag |= KSZ9893_TAIL_TAG_OVERRIDE;
+
+	return skb;
+}
+
+static const struct dsa_device_ops ksz9893_netdev_ops = {
+	.name	= "ksz9893",
+	.proto	= DSA_TAG_PROTO_KSZ9893,
+	.xmit	= ksz9893_xmit,
+	.rcv	= ksz9477_rcv,
+	.needed_tailroom = KSZ_INGRESS_TAG_LEN,
+};
+
+DSA_TAG_DRIVER(ksz9893_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893);
+
+/* For xmit, 2 bytes are added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0 : represents tag override, lookup and valid
+ * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8)
+ *
+ * For rcv, 1 byte is added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0 : zero-based value represents port
+ *	  (eg, 0x00=port1, 0x02=port3, 0x07=port8)
+ */
+#define LAN937X_EGRESS_TAG_LEN		2
+
+#define LAN937X_TAIL_TAG_BLOCKING_OVERRIDE	BIT(11)
+#define LAN937X_TAIL_TAG_LOOKUP			BIT(12)
+#define LAN937X_TAIL_TAG_VALID			BIT(13)
+#define LAN937X_TAIL_TAG_PORT_MASK		7
+
+static struct sk_buff *lan937x_xmit(struct sk_buff *skb,
+				    struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	const struct ethhdr *hdr = eth_hdr(skb);
+	__be16 *tag;
+	u16 val;
+
+	if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
+		return NULL;
+
+	tag = skb_put(skb, LAN937X_EGRESS_TAG_LEN);
+
+	val = BIT(dp->index);
+
+	if (is_link_local_ether_addr(hdr->h_dest))
+		val |= LAN937X_TAIL_TAG_BLOCKING_OVERRIDE;
+
+	/* Tail tag valid bit - This bit should always be set by the CPU */
+	val |= LAN937X_TAIL_TAG_VALID;
+
+	put_unaligned_be16(val, tag);
+
+	return skb;
+}
+
+static const struct dsa_device_ops lan937x_netdev_ops = {
+	.name	= "lan937x",
+	.proto	= DSA_TAG_PROTO_LAN937X,
+	.xmit	= lan937x_xmit,
+	.rcv	= ksz9477_rcv,
+	.needed_tailroom = LAN937X_EGRESS_TAG_LEN,
+};
+
+DSA_TAG_DRIVER(lan937x_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN937X);
+
+static struct dsa_tag_driver *dsa_tag_driver_array[] = {
+	&DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops),
+	&DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops),
+	&DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops),
+	&DSA_TAG_DRIVER_NAME(lan937x_netdev_ops),
+};
+
+module_dsa_tag_drivers(dsa_tag_driver_array);
+
+MODULE_LICENSE("GPL");
diff --git a/net/dsa/tag_lan9303.c b/net/dsa/tag_lan9303.c
new file mode 100644
index 000000000..98d7d7120
--- /dev/null
+++ b/net/dsa/tag_lan9303.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017 Pengutronix, Juergen Borleis <jbe@pengutronix.de>
+ */
+#include <linux/dsa/lan9303.h>
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "dsa_priv.h"
+
+/* To define the outgoing port and to discover the incoming port a regular
+ * VLAN tag is used by the LAN9303. But its VID meaning is 'special':
+ *
+ *       Dest MAC       Src MAC        TAG    Type
+ * ...| 1 2 3 4 5 6 | 1 2 3 4 5 6 | 1 2 3 4 | 1 2 |...
+ *                                |<------->|
+ * TAG:
+ *    |<------------->|
+ *    |  1  2 | 3  4  |
+ *      TPID    VID
+ *     0x8100
+ *
+ * VID bit 3 indicates a request for an ALR lookup.
+ *
+ * If VID bit 3 is zero, then bits 0 and 1 specify the destination port
+ * (0, 1, 2) or broadcast (3) or the source port (1, 2).
+ *
+ * VID bit 4 is used to specify if the STP port state should be overridden.
+ * Required when no forwarding between the external ports should happen.
+ */
+
+#define LAN9303_TAG_LEN 4
+# define LAN9303_TAG_TX_USE_ALR BIT(3)
+# define LAN9303_TAG_TX_STP_OVERRIDE BIT(4)
+# define LAN9303_TAG_RX_IGMP BIT(3)
+# define LAN9303_TAG_RX_STP BIT(4)
+# define LAN9303_TAG_RX_TRAPPED_TO_CPU (LAN9303_TAG_RX_IGMP | \
+					LAN9303_TAG_RX_STP)
+
+/* Decide whether to transmit using ALR lookup, or transmit directly to
+ * port using tag. ALR learning is performed only when using ALR lookup.
+ * If the two external ports are bridged and the frame is unicast,
+ * then use ALR lookup to allow ALR learning on CPU port.
+ * Otherwise transmit directly to port with STP state override.
+ * See also: lan9303_separate_ports() and lan9303.pdf 6.4.10.1
+ */
+static int lan9303_xmit_use_arl(struct dsa_port *dp, u8 *dest_addr)
+{
+	struct lan9303 *chip = dp->ds->priv;
+
+	return chip->is_bridged && !is_multicast_ether_addr(dest_addr);
+}
+
+static struct sk_buff *lan9303_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	__be16 *lan9303_tag;
+	u16 tag;
+
+	/* provide 'LAN9303_TAG_LEN' bytes additional space */
+	skb_push(skb, LAN9303_TAG_LEN);
+
+	/* make room between MACs and Ether-Type */
+	dsa_alloc_etype_header(skb, LAN9303_TAG_LEN);
+
+	lan9303_tag = dsa_etype_header_pos_tx(skb);
+
+	tag = lan9303_xmit_use_arl(dp, skb->data) ?
+		LAN9303_TAG_TX_USE_ALR :
+		dp->index | LAN9303_TAG_TX_STP_OVERRIDE;
+	lan9303_tag[0] = htons(ETH_P_8021Q);
+	lan9303_tag[1] = htons(tag);
+
+	return skb;
+}
+
+static struct sk_buff *lan9303_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	u16 lan9303_tag1;
+	unsigned int source_port;
+
+	if (unlikely(!pskb_may_pull(skb, LAN9303_TAG_LEN))) {
+		dev_warn_ratelimited(&dev->dev,
+				     "Dropping packet, cannot pull\n");
+		return NULL;
+	}
+
+	if (skb_vlan_tag_present(skb)) {
+		lan9303_tag1 = skb_vlan_tag_get(skb);
+		__vlan_hwaccel_clear_tag(skb);
+	} else {
+		skb_push_rcsum(skb, ETH_HLEN);
+		__skb_vlan_pop(skb, &lan9303_tag1);
+		skb_pull_rcsum(skb, ETH_HLEN);
+	}
+
+	source_port = lan9303_tag1 & 0x3;
+
+	skb->dev = dsa_master_find_slave(dev, 0, source_port);
+	if (!skb->dev) {
+		dev_warn_ratelimited(&dev->dev, "Dropping packet due to invalid source port\n");
+		return NULL;
+	}
+
+	if (!(lan9303_tag1 & LAN9303_TAG_RX_TRAPPED_TO_CPU))
+		dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+
+static const struct dsa_device_ops lan9303_netdev_ops = {
+	.name = "lan9303",
+	.proto	= DSA_TAG_PROTO_LAN9303,
+	.xmit = lan9303_xmit,
+	.rcv = lan9303_rcv,
+	.needed_headroom = LAN9303_TAG_LEN,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN9303);
+
+module_dsa_tag_driver(lan9303_netdev_ops);
diff --git a/net/dsa/tag_mtk.c b/net/dsa/tag_mtk.c
new file mode 100644
index 000000000..415d8ece2
--- /dev/null
+++ b/net/dsa/tag_mtk.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Mediatek DSA Tag support
+ * Copyright (C) 2017 Landen Chao <landen.chao@mediatek.com>
+ *		      Sean Wang <sean.wang@mediatek.com>
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/if_vlan.h>
+
+#include "dsa_priv.h"
+
+#define MTK_HDR_LEN		4
+#define MTK_HDR_XMIT_UNTAGGED		0
+#define MTK_HDR_XMIT_TAGGED_TPID_8100	1
+#define MTK_HDR_XMIT_TAGGED_TPID_88A8	2
+#define MTK_HDR_RECV_SOURCE_PORT_MASK	GENMASK(2, 0)
+#define MTK_HDR_XMIT_DP_BIT_MASK	GENMASK(5, 0)
+#define MTK_HDR_XMIT_SA_DIS		BIT(6)
+
+static struct sk_buff *mtk_tag_xmit(struct sk_buff *skb,
+				    struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u8 xmit_tpid;
+	u8 *mtk_tag;
+
+	/* Build the special tag after the MAC Source Address. If VLAN header
+	 * is present, it's required that VLAN header and special tag is
+	 * being combined. Only in this way we can allow the switch can parse
+	 * the both special and VLAN tag at the same time and then look up VLAN
+	 * table with VID.
+	 */
+	switch (skb->protocol) {
+	case htons(ETH_P_8021Q):
+		xmit_tpid = MTK_HDR_XMIT_TAGGED_TPID_8100;
+		break;
+	case htons(ETH_P_8021AD):
+		xmit_tpid = MTK_HDR_XMIT_TAGGED_TPID_88A8;
+		break;
+	default:
+		xmit_tpid = MTK_HDR_XMIT_UNTAGGED;
+		skb_push(skb, MTK_HDR_LEN);
+		dsa_alloc_etype_header(skb, MTK_HDR_LEN);
+	}
+
+	mtk_tag = dsa_etype_header_pos_tx(skb);
+
+	/* Mark tag attribute on special tag insertion to notify hardware
+	 * whether that's a combined special tag with 802.1Q header.
+	 */
+	mtk_tag[0] = xmit_tpid;
+	mtk_tag[1] = (1 << dp->index) & MTK_HDR_XMIT_DP_BIT_MASK;
+
+	/* Tag control information is kept for 802.1Q */
+	if (xmit_tpid == MTK_HDR_XMIT_UNTAGGED) {
+		mtk_tag[2] = 0;
+		mtk_tag[3] = 0;
+	}
+
+	return skb;
+}
+
+static struct sk_buff *mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	u16 hdr;
+	int port;
+	__be16 *phdr;
+
+	if (unlikely(!pskb_may_pull(skb, MTK_HDR_LEN)))
+		return NULL;
+
+	phdr = dsa_etype_header_pos_rx(skb);
+	hdr = ntohs(*phdr);
+
+	/* Remove MTK tag and recalculate checksum. */
+	skb_pull_rcsum(skb, MTK_HDR_LEN);
+
+	dsa_strip_etype_header(skb, MTK_HDR_LEN);
+
+	/* Get source port information */
+	port = (hdr & MTK_HDR_RECV_SOURCE_PORT_MASK);
+
+	skb->dev = dsa_master_find_slave(dev, 0, port);
+	if (!skb->dev)
+		return NULL;
+
+	dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+
+static const struct dsa_device_ops mtk_netdev_ops = {
+	.name		= "mtk",
+	.proto		= DSA_TAG_PROTO_MTK,
+	.xmit		= mtk_tag_xmit,
+	.rcv		= mtk_tag_rcv,
+	.needed_headroom = MTK_HDR_LEN,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_MTK);
+
+module_dsa_tag_driver(mtk_netdev_ops);
diff --git a/net/dsa/tag_ocelot.c b/net/dsa/tag_ocelot.c
new file mode 100644
index 000000000..0d81f172b
--- /dev/null
+++ b/net/dsa/tag_ocelot.c
@@ -0,0 +1,216 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2019 NXP
+ */
+#include <linux/dsa/ocelot.h>
+#include "dsa_priv.h"
+
+/* If the port is under a VLAN-aware bridge, remove the VLAN header from the
+ * payload and move it into the DSA tag, which will make the switch classify
+ * the packet to the bridge VLAN. Otherwise, leave the classified VLAN at zero,
+ * which is the pvid of standalone and VLAN-unaware bridge ports.
+ */
+static void ocelot_xmit_get_vlan_info(struct sk_buff *skb, struct dsa_port *dp,
+				      u64 *vlan_tci, u64 *tag_type)
+{
+	struct net_device *br = dsa_port_bridge_dev_get(dp);
+	struct vlan_ethhdr *hdr;
+	u16 proto, tci;
+
+	if (!br || !br_vlan_enabled(br)) {
+		*vlan_tci = 0;
+		*tag_type = IFH_TAG_TYPE_C;
+		return;
+	}
+
+	hdr = (struct vlan_ethhdr *)skb_mac_header(skb);
+	br_vlan_get_proto(br, &proto);
+
+	if (ntohs(hdr->h_vlan_proto) == proto) {
+		__skb_vlan_pop(skb, &tci);
+		*vlan_tci = tci;
+	} else {
+		rcu_read_lock();
+		br_vlan_get_pvid_rcu(br, &tci);
+		rcu_read_unlock();
+		*vlan_tci = tci;
+	}
+
+	*tag_type = (proto != ETH_P_8021Q) ? IFH_TAG_TYPE_S : IFH_TAG_TYPE_C;
+}
+
+static void ocelot_xmit_common(struct sk_buff *skb, struct net_device *netdev,
+			       __be32 ifh_prefix, void **ifh)
+{
+	struct dsa_port *dp = dsa_slave_to_port(netdev);
+	struct dsa_switch *ds = dp->ds;
+	u64 vlan_tci, tag_type;
+	void *injection;
+	__be32 *prefix;
+	u32 rew_op = 0;
+	u64 qos_class;
+
+	ocelot_xmit_get_vlan_info(skb, dp, &vlan_tci, &tag_type);
+
+	qos_class = netdev_get_num_tc(netdev) ?
+		    netdev_get_prio_tc_map(netdev, skb->priority) : skb->priority;
+
+	injection = skb_push(skb, OCELOT_TAG_LEN);
+	prefix = skb_push(skb, OCELOT_SHORT_PREFIX_LEN);
+
+	*prefix = ifh_prefix;
+	memset(injection, 0, OCELOT_TAG_LEN);
+	ocelot_ifh_set_bypass(injection, 1);
+	ocelot_ifh_set_src(injection, ds->num_ports);
+	ocelot_ifh_set_qos_class(injection, qos_class);
+	ocelot_ifh_set_vlan_tci(injection, vlan_tci);
+	ocelot_ifh_set_tag_type(injection, tag_type);
+
+	rew_op = ocelot_ptp_rew_op(skb);
+	if (rew_op)
+		ocelot_ifh_set_rew_op(injection, rew_op);
+
+	*ifh = injection;
+}
+
+static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
+				   struct net_device *netdev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(netdev);
+	void *injection;
+
+	ocelot_xmit_common(skb, netdev, cpu_to_be32(0x8880000a), &injection);
+	ocelot_ifh_set_dest(injection, BIT_ULL(dp->index));
+
+	return skb;
+}
+
+static struct sk_buff *seville_xmit(struct sk_buff *skb,
+				    struct net_device *netdev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(netdev);
+	void *injection;
+
+	ocelot_xmit_common(skb, netdev, cpu_to_be32(0x88800005), &injection);
+	seville_ifh_set_dest(injection, BIT_ULL(dp->index));
+
+	return skb;
+}
+
+static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
+				  struct net_device *netdev)
+{
+	u64 src_port, qos_class;
+	u64 vlan_tci, tag_type;
+	u8 *start = skb->data;
+	struct dsa_port *dp;
+	u8 *extraction;
+	u16 vlan_tpid;
+	u64 rew_val;
+
+	/* Revert skb->data by the amount consumed by the DSA master,
+	 * so it points to the beginning of the frame.
+	 */
+	skb_push(skb, ETH_HLEN);
+	/* We don't care about the short prefix, it is just for easy entrance
+	 * into the DSA master's RX filter. Discard it now by moving it into
+	 * the headroom.
+	 */
+	skb_pull(skb, OCELOT_SHORT_PREFIX_LEN);
+	/* And skb->data now points to the extraction frame header.
+	 * Keep a pointer to it.
+	 */
+	extraction = skb->data;
+	/* Now the EFH is part of the headroom as well */
+	skb_pull(skb, OCELOT_TAG_LEN);
+	/* Reset the pointer to the real MAC header */
+	skb_reset_mac_header(skb);
+	skb_reset_mac_len(skb);
+	/* And move skb->data to the correct location again */
+	skb_pull(skb, ETH_HLEN);
+
+	/* Remove from inet csum the extraction header */
+	skb_postpull_rcsum(skb, start, OCELOT_TOTAL_TAG_LEN);
+
+	ocelot_xfh_get_src_port(extraction, &src_port);
+	ocelot_xfh_get_qos_class(extraction, &qos_class);
+	ocelot_xfh_get_tag_type(extraction, &tag_type);
+	ocelot_xfh_get_vlan_tci(extraction, &vlan_tci);
+	ocelot_xfh_get_rew_val(extraction, &rew_val);
+
+	skb->dev = dsa_master_find_slave(netdev, 0, src_port);
+	if (!skb->dev)
+		/* The switch will reflect back some frames sent through
+		 * sockets opened on the bare DSA master. These will come back
+		 * with src_port equal to the index of the CPU port, for which
+		 * there is no slave registered. So don't print any error
+		 * message here (ignore and drop those frames).
+		 */
+		return NULL;
+
+	dsa_default_offload_fwd_mark(skb);
+	skb->priority = qos_class;
+	OCELOT_SKB_CB(skb)->tstamp_lo = rew_val;
+
+	/* Ocelot switches copy frames unmodified to the CPU. However, it is
+	 * possible for the user to request a VLAN modification through
+	 * VCAP_IS1_ACT_VID_REPLACE_ENA. In this case, what will happen is that
+	 * the VLAN ID field from the Extraction Header gets updated, but the
+	 * 802.1Q header does not (the classified VLAN only becomes visible on
+	 * egress through the "port tag" of front-panel ports).
+	 * So, for traffic extracted by the CPU, we want to pick up the
+	 * classified VLAN and manually replace the existing 802.1Q header from
+	 * the packet with it, so that the operating system is always up to
+	 * date with the result of tc-vlan actions.
+	 * NOTE: In VLAN-unaware mode, we don't want to do that, we want the
+	 * frame to remain unmodified, because the classified VLAN is always
+	 * equal to the pvid of the ingress port and should not be used for
+	 * processing.
+	 */
+	dp = dsa_slave_to_port(skb->dev);
+	vlan_tpid = tag_type ? ETH_P_8021AD : ETH_P_8021Q;
+
+	if (dsa_port_is_vlan_filtering(dp) &&
+	    eth_hdr(skb)->h_proto == htons(vlan_tpid)) {
+		u16 dummy_vlan_tci;
+
+		skb_push_rcsum(skb, ETH_HLEN);
+		__skb_vlan_pop(skb, &dummy_vlan_tci);
+		skb_pull_rcsum(skb, ETH_HLEN);
+		__vlan_hwaccel_put_tag(skb, htons(vlan_tpid), vlan_tci);
+	}
+
+	return skb;
+}
+
+static const struct dsa_device_ops ocelot_netdev_ops = {
+	.name			= "ocelot",
+	.proto			= DSA_TAG_PROTO_OCELOT,
+	.xmit			= ocelot_xmit,
+	.rcv			= ocelot_rcv,
+	.needed_headroom	= OCELOT_TOTAL_TAG_LEN,
+	.promisc_on_master	= true,
+};
+
+DSA_TAG_DRIVER(ocelot_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT);
+
+static const struct dsa_device_ops seville_netdev_ops = {
+	.name			= "seville",
+	.proto			= DSA_TAG_PROTO_SEVILLE,
+	.xmit			= seville_xmit,
+	.rcv			= ocelot_rcv,
+	.needed_headroom	= OCELOT_TOTAL_TAG_LEN,
+	.promisc_on_master	= true,
+};
+
+DSA_TAG_DRIVER(seville_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SEVILLE);
+
+static struct dsa_tag_driver *ocelot_tag_driver_array[] = {
+	&DSA_TAG_DRIVER_NAME(ocelot_netdev_ops),
+	&DSA_TAG_DRIVER_NAME(seville_netdev_ops),
+};
+
+module_dsa_tag_drivers(ocelot_tag_driver_array);
+
+MODULE_LICENSE("GPL v2");
diff --git a/net/dsa/tag_ocelot_8021q.c b/net/dsa/tag_ocelot_8021q.c
new file mode 100644
index 000000000..37ccf0040
--- /dev/null
+++ b/net/dsa/tag_ocelot_8021q.c
@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2020-2021 NXP
+ *
+ * An implementation of the software-defined tag_8021q.c tagger format, which
+ * also preserves full functionality under a vlan_filtering bridge. It does
+ * this by using the TCAM engines for:
+ * - pushing the RX VLAN as a second, outer tag, on egress towards the CPU port
+ * - redirecting towards the correct front port based on TX VLAN and popping
+ *   that on egress
+ */
+#include <linux/dsa/8021q.h>
+#include <linux/dsa/ocelot.h>
+#include "dsa_priv.h"
+
+struct ocelot_8021q_tagger_private {
+	struct ocelot_8021q_tagger_data data; /* Must be first */
+	struct kthread_worker *xmit_worker;
+};
+
+static struct sk_buff *ocelot_defer_xmit(struct dsa_port *dp,
+					 struct sk_buff *skb)
+{
+	struct ocelot_8021q_tagger_private *priv = dp->ds->tagger_data;
+	struct ocelot_8021q_tagger_data *data = &priv->data;
+	void (*xmit_work_fn)(struct kthread_work *work);
+	struct felix_deferred_xmit_work *xmit_work;
+	struct kthread_worker *xmit_worker;
+
+	xmit_work_fn = data->xmit_work_fn;
+	xmit_worker = priv->xmit_worker;
+
+	if (!xmit_work_fn || !xmit_worker)
+		return NULL;
+
+	/* PTP over IP packets need UDP checksumming. We may have inherited
+	 * NETIF_F_HW_CSUM from the DSA master, but these packets are not sent
+	 * through the DSA master, so calculate the checksum here.
+	 */
+	if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
+		return NULL;
+
+	xmit_work = kzalloc(sizeof(*xmit_work), GFP_ATOMIC);
+	if (!xmit_work)
+		return NULL;
+
+	/* Calls felix_port_deferred_xmit in felix.c */
+	kthread_init_work(&xmit_work->work, xmit_work_fn);
+	/* Increase refcount so the kfree_skb in dsa_slave_xmit
+	 * won't really free the packet.
+	 */
+	xmit_work->dp = dp;
+	xmit_work->skb = skb_get(skb);
+
+	kthread_queue_work(xmit_worker, &xmit_work->work);
+
+	return NULL;
+}
+
+static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
+				   struct net_device *netdev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(netdev);
+	u16 queue_mapping = skb_get_queue_mapping(skb);
+	u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
+	u16 tx_vid = dsa_tag_8021q_standalone_vid(dp);
+	struct ethhdr *hdr = eth_hdr(skb);
+
+	if (ocelot_ptp_rew_op(skb) || is_link_local_ether_addr(hdr->h_dest))
+		return ocelot_defer_xmit(dp, skb);
+
+	return dsa_8021q_xmit(skb, netdev, ETH_P_8021Q,
+			      ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
+}
+
+static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
+				  struct net_device *netdev)
+{
+	int src_port, switch_id;
+
+	dsa_8021q_rcv(skb, &src_port, &switch_id, NULL);
+
+	skb->dev = dsa_master_find_slave(netdev, switch_id, src_port);
+	if (!skb->dev)
+		return NULL;
+
+	dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+
+static void ocelot_disconnect(struct dsa_switch *ds)
+{
+	struct ocelot_8021q_tagger_private *priv = ds->tagger_data;
+
+	kthread_destroy_worker(priv->xmit_worker);
+	kfree(priv);
+	ds->tagger_data = NULL;
+}
+
+static int ocelot_connect(struct dsa_switch *ds)
+{
+	struct ocelot_8021q_tagger_private *priv;
+	int err;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->xmit_worker = kthread_create_worker(0, "felix_xmit");
+	if (IS_ERR(priv->xmit_worker)) {
+		err = PTR_ERR(priv->xmit_worker);
+		kfree(priv);
+		return err;
+	}
+
+	ds->tagger_data = priv;
+
+	return 0;
+}
+
+static const struct dsa_device_ops ocelot_8021q_netdev_ops = {
+	.name			= "ocelot-8021q",
+	.proto			= DSA_TAG_PROTO_OCELOT_8021Q,
+	.xmit			= ocelot_xmit,
+	.rcv			= ocelot_rcv,
+	.connect		= ocelot_connect,
+	.disconnect		= ocelot_disconnect,
+	.needed_headroom	= VLAN_HLEN,
+	.promisc_on_master	= true,
+};
+
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT_8021Q);
+
+module_dsa_tag_driver(ocelot_8021q_netdev_ops);
diff --git a/net/dsa/tag_qca.c b/net/dsa/tag_qca.c
new file mode 100644
index 000000000..57d2e00f1
--- /dev/null
+++ b/net/dsa/tag_qca.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2015, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/bitfield.h>
+#include <net/dsa.h>
+#include <linux/dsa/tag_qca.h>
+
+#include "dsa_priv.h"
+
+static struct sk_buff *qca_tag_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	__be16 *phdr;
+	u16 hdr;
+
+	skb_push(skb, QCA_HDR_LEN);
+
+	dsa_alloc_etype_header(skb, QCA_HDR_LEN);
+	phdr = dsa_etype_header_pos_tx(skb);
+
+	/* Set the version field, and set destination port information */
+	hdr = FIELD_PREP(QCA_HDR_XMIT_VERSION, QCA_HDR_VERSION);
+	hdr |= QCA_HDR_XMIT_FROM_CPU;
+	hdr |= FIELD_PREP(QCA_HDR_XMIT_DP_BIT, BIT(dp->index));
+
+	*phdr = htons(hdr);
+
+	return skb;
+}
+
+static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	struct qca_tagger_data *tagger_data;
+	struct dsa_port *dp = dev->dsa_ptr;
+	struct dsa_switch *ds = dp->ds;
+	u8 ver, pk_type;
+	__be16 *phdr;
+	int port;
+	u16 hdr;
+
+	BUILD_BUG_ON(sizeof(struct qca_mgmt_ethhdr) != QCA_HDR_MGMT_HEADER_LEN + QCA_HDR_LEN);
+
+	tagger_data = ds->tagger_data;
+
+	if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN)))
+		return NULL;
+
+	phdr = dsa_etype_header_pos_rx(skb);
+	hdr = ntohs(*phdr);
+
+	/* Make sure the version is correct */
+	ver = FIELD_GET(QCA_HDR_RECV_VERSION, hdr);
+	if (unlikely(ver != QCA_HDR_VERSION))
+		return NULL;
+
+	/* Get pk type */
+	pk_type = FIELD_GET(QCA_HDR_RECV_TYPE, hdr);
+
+	/* Ethernet mgmt read/write packet */
+	if (pk_type == QCA_HDR_RECV_TYPE_RW_REG_ACK) {
+		if (likely(tagger_data->rw_reg_ack_handler))
+			tagger_data->rw_reg_ack_handler(ds, skb);
+		return NULL;
+	}
+
+	/* Ethernet MIB counter packet */
+	if (pk_type == QCA_HDR_RECV_TYPE_MIB) {
+		if (likely(tagger_data->mib_autocast_handler))
+			tagger_data->mib_autocast_handler(ds, skb);
+		return NULL;
+	}
+
+	/* Remove QCA tag and recalculate checksum */
+	skb_pull_rcsum(skb, QCA_HDR_LEN);
+	dsa_strip_etype_header(skb, QCA_HDR_LEN);
+
+	/* Get source port information */
+	port = FIELD_GET(QCA_HDR_RECV_SOURCE_PORT, hdr);
+
+	skb->dev = dsa_master_find_slave(dev, 0, port);
+	if (!skb->dev)
+		return NULL;
+
+	return skb;
+}
+
+static int qca_tag_connect(struct dsa_switch *ds)
+{
+	struct qca_tagger_data *tagger_data;
+
+	tagger_data = kzalloc(sizeof(*tagger_data), GFP_KERNEL);
+	if (!tagger_data)
+		return -ENOMEM;
+
+	ds->tagger_data = tagger_data;
+
+	return 0;
+}
+
+static void qca_tag_disconnect(struct dsa_switch *ds)
+{
+	kfree(ds->tagger_data);
+	ds->tagger_data = NULL;
+}
+
+static const struct dsa_device_ops qca_netdev_ops = {
+	.name	= "qca",
+	.proto	= DSA_TAG_PROTO_QCA,
+	.connect = qca_tag_connect,
+	.disconnect = qca_tag_disconnect,
+	.xmit	= qca_tag_xmit,
+	.rcv	= qca_tag_rcv,
+	.needed_headroom = QCA_HDR_LEN,
+	.promisc_on_master = true,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_QCA);
+
+module_dsa_tag_driver(qca_netdev_ops);
diff --git a/net/dsa/tag_rtl4_a.c b/net/dsa/tag_rtl4_a.c
new file mode 100644
index 000000000..6d928ee3e
--- /dev/null
+++ b/net/dsa/tag_rtl4_a.c
@@ -0,0 +1,124 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Handler for Realtek 4 byte DSA switch tags
+ * Currently only supports protocol "A" found in RTL8366RB
+ * Copyright (c) 2020 Linus Walleij <linus.walleij@linaro.org>
+ *
+ * This "proprietary tag" header looks like so:
+ *
+ * -------------------------------------------------
+ * | MAC DA | MAC SA | 0x8899 | 2 bytes tag | Type |
+ * -------------------------------------------------
+ *
+ * The 2 bytes tag form a 16 bit big endian word. The exact
+ * meaning has been guessed from packet dumps from ingress
+ * frames.
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/bits.h>
+
+#include "dsa_priv.h"
+
+#define RTL4_A_HDR_LEN		4
+#define RTL4_A_ETHERTYPE	0x8899
+#define RTL4_A_PROTOCOL_SHIFT	12
+/*
+ * 0x1 = Realtek Remote Control protocol (RRCP)
+ * 0x2/0x3 seems to be used for loopback testing
+ * 0x9 = RTL8306 DSA protocol
+ * 0xa = RTL8366RB DSA protocol
+ */
+#define RTL4_A_PROTOCOL_RTL8366RB	0xa
+
+static struct sk_buff *rtl4a_tag_xmit(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	__be16 *p;
+	u8 *tag;
+	u16 out;
+
+	/* Pad out to at least 60 bytes */
+	if (unlikely(__skb_put_padto(skb, ETH_ZLEN, false)))
+		return NULL;
+
+	netdev_dbg(dev, "add realtek tag to package to port %d\n",
+		   dp->index);
+	skb_push(skb, RTL4_A_HDR_LEN);
+
+	dsa_alloc_etype_header(skb, RTL4_A_HDR_LEN);
+	tag = dsa_etype_header_pos_tx(skb);
+
+	/* Set Ethertype */
+	p = (__be16 *)tag;
+	*p = htons(RTL4_A_ETHERTYPE);
+
+	out = (RTL4_A_PROTOCOL_RTL8366RB << RTL4_A_PROTOCOL_SHIFT);
+	/* The lower bits indicate the port number */
+	out |= BIT(dp->index);
+
+	p = (__be16 *)(tag + 2);
+	*p = htons(out);
+
+	return skb;
+}
+
+static struct sk_buff *rtl4a_tag_rcv(struct sk_buff *skb,
+				     struct net_device *dev)
+{
+	u16 protport;
+	__be16 *p;
+	u16 etype;
+	u8 *tag;
+	u8 prot;
+	u8 port;
+
+	if (unlikely(!pskb_may_pull(skb, RTL4_A_HDR_LEN)))
+		return NULL;
+
+	tag = dsa_etype_header_pos_rx(skb);
+	p = (__be16 *)tag;
+	etype = ntohs(*p);
+	if (etype != RTL4_A_ETHERTYPE) {
+		/* Not custom, just pass through */
+		netdev_dbg(dev, "non-realtek ethertype 0x%04x\n", etype);
+		return skb;
+	}
+	p = (__be16 *)(tag + 2);
+	protport = ntohs(*p);
+	/* The 4 upper bits are the protocol */
+	prot = (protport >> RTL4_A_PROTOCOL_SHIFT) & 0x0f;
+	if (prot != RTL4_A_PROTOCOL_RTL8366RB) {
+		netdev_err(dev, "unknown realtek protocol 0x%01x\n", prot);
+		return NULL;
+	}
+	port = protport & 0xff;
+
+	skb->dev = dsa_master_find_slave(dev, 0, port);
+	if (!skb->dev) {
+		netdev_dbg(dev, "could not find slave for port %d\n", port);
+		return NULL;
+	}
+
+	/* Remove RTL4 tag and recalculate checksum */
+	skb_pull_rcsum(skb, RTL4_A_HDR_LEN);
+
+	dsa_strip_etype_header(skb, RTL4_A_HDR_LEN);
+
+	dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+
+static const struct dsa_device_ops rtl4a_netdev_ops = {
+	.name	= "rtl4a",
+	.proto	= DSA_TAG_PROTO_RTL4_A,
+	.xmit	= rtl4a_tag_xmit,
+	.rcv	= rtl4a_tag_rcv,
+	.needed_headroom = RTL4_A_HDR_LEN,
+};
+module_dsa_tag_driver(rtl4a_netdev_ops);
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL4_A);
diff --git a/net/dsa/tag_rtl8_4.c b/net/dsa/tag_rtl8_4.c
new file mode 100644
index 000000000..a593ead7f
--- /dev/null
+++ b/net/dsa/tag_rtl8_4.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Handler for Realtek 8 byte switch tags
+ *
+ * Copyright (C) 2021 Alvin Šipraga <alsi@bang-olufsen.dk>
+ *
+ * NOTE: Currently only supports protocol "4" found in the RTL8365MB, hence
+ * named tag_rtl8_4.
+ *
+ * This tag has the following format:
+ *
+ *  0                                  7|8                                 15
+ *  |-----------------------------------+-----------------------------------|---
+ *  |                               (16-bit)                                | ^
+ *  |                       Realtek EtherType [0x8899]                      | |
+ *  |-----------------------------------+-----------------------------------| 8
+ *  |              (8-bit)              |              (8-bit)              |
+ *  |          Protocol [0x04]          |              REASON               | b
+ *  |-----------------------------------+-----------------------------------| y
+ *  |   (1)  | (1) | (2) |   (1)  | (3) | (1)  | (1) |    (1)    |   (5)    | t
+ *  | FID_EN |  X  | FID | PRI_EN | PRI | KEEP |  X  | LEARN_DIS |    X     | e
+ *  |-----------------------------------+-----------------------------------| s
+ *  |   (1)  |                       (15-bit)                               | |
+ *  |  ALLOW |                        TX/RX                                 | v
+ *  |-----------------------------------+-----------------------------------|---
+ *
+ * With the following field descriptions:
+ *
+ *    field      | description
+ *   ------------+-------------
+ *    Realtek    | 0x8899: indicates that this is a proprietary Realtek tag;
+ *     EtherType |         note that Realtek uses the same EtherType for
+ *               |         other incompatible tag formats (e.g. tag_rtl4_a.c)
+ *    Protocol   | 0x04: indicates that this tag conforms to this format
+ *    X          | reserved
+ *   ------------+-------------
+ *    REASON     | reason for forwarding packet to CPU
+ *               | 0: packet was forwarded or flooded to CPU
+ *               | 80: packet was trapped to CPU
+ *    FID_EN     | 1: packet has an FID
+ *               | 0: no FID
+ *    FID        | FID of packet (if FID_EN=1)
+ *    PRI_EN     | 1: force priority of packet
+ *               | 0: don't force priority
+ *    PRI        | priority of packet (if PRI_EN=1)
+ *    KEEP       | preserve packet VLAN tag format
+ *    LEARN_DIS  | don't learn the source MAC address of the packet
+ *    ALLOW      | 1: treat TX/RX field as an allowance port mask, meaning the
+ *               |    packet may only be forwarded to ports specified in the
+ *               |    mask
+ *               | 0: no allowance port mask, TX/RX field is the forwarding
+ *               |    port mask
+ *    TX/RX      | TX (switch->CPU): port number the packet was received on
+ *               | RX (CPU->switch): forwarding port mask (if ALLOW=0)
+ *               |                   allowance port mask (if ALLOW=1)
+ *
+ * The tag can be positioned before Ethertype, using tag "rtl8_4":
+ *
+ *  +--------+--------+------------+------+-----
+ *  | MAC DA | MAC SA | 8 byte tag | Type | ...
+ *  +--------+--------+------------+------+-----
+ *
+ * The tag can also appear between the end of the payload and before the CRC,
+ * using tag "rtl8_4t":
+ *
+ * +--------+--------+------+-----+---------+------------+-----+
+ * | MAC DA | MAC SA | TYPE | ... | payload | 8-byte tag | CRC |
+ * +--------+--------+------+-----+---------+------------+-----+
+ *
+ * The added bytes after the payload will break most checksums, either in
+ * software or hardware. To avoid this issue, if the checksum is still pending,
+ * this tagger checksums the packet in software before adding the tag.
+ *
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/etherdevice.h>
+
+#include "dsa_priv.h"
+
+/* Protocols supported:
+ *
+ * 0x04 = RTL8365MB DSA protocol
+ */
+
+#define RTL8_4_TAG_LEN			8
+
+#define RTL8_4_PROTOCOL			GENMASK(15, 8)
+#define   RTL8_4_PROTOCOL_RTL8365MB	0x04
+#define RTL8_4_REASON			GENMASK(7, 0)
+#define   RTL8_4_REASON_FORWARD		0
+#define   RTL8_4_REASON_TRAP		80
+
+#define RTL8_4_LEARN_DIS		BIT(5)
+
+#define RTL8_4_TX			GENMASK(3, 0)
+#define RTL8_4_RX			GENMASK(10, 0)
+
+static void rtl8_4_write_tag(struct sk_buff *skb, struct net_device *dev,
+			     void *tag)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	__be16 tag16[RTL8_4_TAG_LEN / 2];
+
+	/* Set Realtek EtherType */
+	tag16[0] = htons(ETH_P_REALTEK);
+
+	/* Set Protocol; zero REASON */
+	tag16[1] = htons(FIELD_PREP(RTL8_4_PROTOCOL, RTL8_4_PROTOCOL_RTL8365MB));
+
+	/* Zero FID_EN, FID, PRI_EN, PRI, KEEP; set LEARN_DIS */
+	tag16[2] = htons(FIELD_PREP(RTL8_4_LEARN_DIS, 1));
+
+	/* Zero ALLOW; set RX (CPU->switch) forwarding port mask */
+	tag16[3] = htons(FIELD_PREP(RTL8_4_RX, BIT(dp->index)));
+
+	memcpy(tag, tag16, RTL8_4_TAG_LEN);
+}
+
+static struct sk_buff *rtl8_4_tag_xmit(struct sk_buff *skb,
+				       struct net_device *dev)
+{
+	skb_push(skb, RTL8_4_TAG_LEN);
+
+	dsa_alloc_etype_header(skb, RTL8_4_TAG_LEN);
+
+	rtl8_4_write_tag(skb, dev, dsa_etype_header_pos_tx(skb));
+
+	return skb;
+}
+
+static struct sk_buff *rtl8_4t_tag_xmit(struct sk_buff *skb,
+					struct net_device *dev)
+{
+	/* Calculate the checksum here if not done yet as trailing tags will
+	 * break either software or hardware based checksum
+	 */
+	if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
+		return NULL;
+
+	rtl8_4_write_tag(skb, dev, skb_put(skb, RTL8_4_TAG_LEN));
+
+	return skb;
+}
+
+static int rtl8_4_read_tag(struct sk_buff *skb, struct net_device *dev,
+			   void *tag)
+{
+	__be16 tag16[RTL8_4_TAG_LEN / 2];
+	u16 etype;
+	u8 reason;
+	u8 proto;
+	u8 port;
+
+	memcpy(tag16, tag, RTL8_4_TAG_LEN);
+
+	/* Parse Realtek EtherType */
+	etype = ntohs(tag16[0]);
+	if (unlikely(etype != ETH_P_REALTEK)) {
+		dev_warn_ratelimited(&dev->dev,
+				     "non-realtek ethertype 0x%04x\n", etype);
+		return -EPROTO;
+	}
+
+	/* Parse Protocol */
+	proto = FIELD_GET(RTL8_4_PROTOCOL, ntohs(tag16[1]));
+	if (unlikely(proto != RTL8_4_PROTOCOL_RTL8365MB)) {
+		dev_warn_ratelimited(&dev->dev,
+				     "unknown realtek protocol 0x%02x\n",
+				     proto);
+		return -EPROTO;
+	}
+
+	/* Parse REASON */
+	reason = FIELD_GET(RTL8_4_REASON, ntohs(tag16[1]));
+
+	/* Parse TX (switch->CPU) */
+	port = FIELD_GET(RTL8_4_TX, ntohs(tag16[3]));
+	skb->dev = dsa_master_find_slave(dev, 0, port);
+	if (!skb->dev) {
+		dev_warn_ratelimited(&dev->dev,
+				     "could not find slave for port %d\n",
+				     port);
+		return -ENOENT;
+	}
+
+	if (reason != RTL8_4_REASON_TRAP)
+		dsa_default_offload_fwd_mark(skb);
+
+	return 0;
+}
+
+static struct sk_buff *rtl8_4_tag_rcv(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	if (unlikely(!pskb_may_pull(skb, RTL8_4_TAG_LEN)))
+		return NULL;
+
+	if (unlikely(rtl8_4_read_tag(skb, dev, dsa_etype_header_pos_rx(skb))))
+		return NULL;
+
+	/* Remove tag and recalculate checksum */
+	skb_pull_rcsum(skb, RTL8_4_TAG_LEN);
+
+	dsa_strip_etype_header(skb, RTL8_4_TAG_LEN);
+
+	return skb;
+}
+
+static struct sk_buff *rtl8_4t_tag_rcv(struct sk_buff *skb,
+				       struct net_device *dev)
+{
+	if (skb_linearize(skb))
+		return NULL;
+
+	if (unlikely(rtl8_4_read_tag(skb, dev, skb_tail_pointer(skb) - RTL8_4_TAG_LEN)))
+		return NULL;
+
+	if (pskb_trim_rcsum(skb, skb->len - RTL8_4_TAG_LEN))
+		return NULL;
+
+	return skb;
+}
+
+/* Ethertype version */
+static const struct dsa_device_ops rtl8_4_netdev_ops = {
+	.name = "rtl8_4",
+	.proto = DSA_TAG_PROTO_RTL8_4,
+	.xmit = rtl8_4_tag_xmit,
+	.rcv = rtl8_4_tag_rcv,
+	.needed_headroom = RTL8_4_TAG_LEN,
+};
+
+DSA_TAG_DRIVER(rtl8_4_netdev_ops);
+
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL8_4);
+
+/* Tail version */
+static const struct dsa_device_ops rtl8_4t_netdev_ops = {
+	.name = "rtl8_4t",
+	.proto = DSA_TAG_PROTO_RTL8_4T,
+	.xmit = rtl8_4t_tag_xmit,
+	.rcv = rtl8_4t_tag_rcv,
+	.needed_tailroom = RTL8_4_TAG_LEN,
+};
+
+DSA_TAG_DRIVER(rtl8_4t_netdev_ops);
+
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_RTL8_4T);
+
+static struct dsa_tag_driver *dsa_tag_drivers[] = {
+	&DSA_TAG_DRIVER_NAME(rtl8_4_netdev_ops),
+	&DSA_TAG_DRIVER_NAME(rtl8_4t_netdev_ops),
+};
+module_dsa_tag_drivers(dsa_tag_drivers);
+
+MODULE_LICENSE("GPL");
diff --git a/net/dsa/tag_rzn1_a5psw.c b/net/dsa/tag_rzn1_a5psw.c
new file mode 100644
index 000000000..e2a5ee6ae
--- /dev/null
+++ b/net/dsa/tag_rzn1_a5psw.c
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 Schneider Electric
+ *
+ * Clément Léger <clement.leger@bootlin.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/etherdevice.h>
+#include <linux/if_ether.h>
+#include <net/dsa.h>
+
+#include "dsa_priv.h"
+
+/* To define the outgoing port and to discover the incoming port a TAG is
+ * inserted after Src MAC :
+ *
+ *       Dest MAC       Src MAC           TAG         Type
+ * ...| 1 2 3 4 5 6 | 1 2 3 4 5 6 | 1 2 3 4 5 6 7 8 | 1 2 |...
+ *                                |<--------------->|
+ *
+ * See struct a5psw_tag for layout
+ */
+
+#define ETH_P_DSA_A5PSW			0xE001
+#define A5PSW_TAG_LEN			8
+#define A5PSW_CTRL_DATA_FORCE_FORWARD	BIT(0)
+/* This is both used for xmit tag and rcv tagging */
+#define A5PSW_CTRL_DATA_PORT		GENMASK(3, 0)
+
+struct a5psw_tag {
+	__be16 ctrl_tag;
+	__be16 ctrl_data;
+	__be16 ctrl_data2_hi;
+	__be16 ctrl_data2_lo;
+};
+
+static struct sk_buff *a5psw_tag_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct a5psw_tag *ptag;
+	u32 data2_val;
+
+	BUILD_BUG_ON(sizeof(*ptag) != A5PSW_TAG_LEN);
+
+	/* The Ethernet switch we are interfaced with needs packets to be at
+	 * least 60 bytes otherwise they will be discarded when they enter the
+	 * switch port logic.
+	 */
+	if (__skb_put_padto(skb, ETH_ZLEN, false))
+		return NULL;
+
+	/* provide 'A5PSW_TAG_LEN' bytes additional space */
+	skb_push(skb, A5PSW_TAG_LEN);
+
+	/* make room between MACs and Ether-Type to insert tag */
+	dsa_alloc_etype_header(skb, A5PSW_TAG_LEN);
+
+	ptag = dsa_etype_header_pos_tx(skb);
+
+	data2_val = FIELD_PREP(A5PSW_CTRL_DATA_PORT, BIT(dp->index));
+	ptag->ctrl_tag = htons(ETH_P_DSA_A5PSW);
+	ptag->ctrl_data = htons(A5PSW_CTRL_DATA_FORCE_FORWARD);
+	ptag->ctrl_data2_lo = htons(data2_val);
+	ptag->ctrl_data2_hi = 0;
+
+	return skb;
+}
+
+static struct sk_buff *a5psw_tag_rcv(struct sk_buff *skb,
+				     struct net_device *dev)
+{
+	struct a5psw_tag *tag;
+	int port;
+
+	if (unlikely(!pskb_may_pull(skb, A5PSW_TAG_LEN))) {
+		dev_warn_ratelimited(&dev->dev,
+				     "Dropping packet, cannot pull\n");
+		return NULL;
+	}
+
+	tag = dsa_etype_header_pos_rx(skb);
+
+	if (tag->ctrl_tag != htons(ETH_P_DSA_A5PSW)) {
+		dev_warn_ratelimited(&dev->dev, "Dropping packet due to invalid TAG marker\n");
+		return NULL;
+	}
+
+	port = FIELD_GET(A5PSW_CTRL_DATA_PORT, ntohs(tag->ctrl_data));
+
+	skb->dev = dsa_master_find_slave(dev, 0, port);
+	if (!skb->dev)
+		return NULL;
+
+	skb_pull_rcsum(skb, A5PSW_TAG_LEN);
+	dsa_strip_etype_header(skb, A5PSW_TAG_LEN);
+
+	dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+
+static const struct dsa_device_ops a5psw_netdev_ops = {
+	.name	= "a5psw",
+	.proto	= DSA_TAG_PROTO_RZN1_A5PSW,
+	.xmit	= a5psw_tag_xmit,
+	.rcv	= a5psw_tag_rcv,
+	.needed_headroom = A5PSW_TAG_LEN,
+};
+
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_A5PSW);
+module_dsa_tag_driver(a5psw_netdev_ops);
diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
new file mode 100644
index 000000000..143348962
--- /dev/null
+++ b/net/dsa/tag_sja1105.c
@@ -0,0 +1,804 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019, Vladimir Oltean <olteanv@gmail.com>
+ */
+#include <linux/if_vlan.h>
+#include <linux/dsa/sja1105.h>
+#include <linux/dsa/8021q.h>
+#include <linux/packing.h>
+#include "dsa_priv.h"
+
+/* Is this a TX or an RX header? */
+#define SJA1110_HEADER_HOST_TO_SWITCH		BIT(15)
+
+/* RX header */
+#define SJA1110_RX_HEADER_IS_METADATA		BIT(14)
+#define SJA1110_RX_HEADER_HOST_ONLY		BIT(13)
+#define SJA1110_RX_HEADER_HAS_TRAILER		BIT(12)
+
+/* Trap-to-host format (no trailer present) */
+#define SJA1110_RX_HEADER_SRC_PORT(x)		(((x) & GENMASK(7, 4)) >> 4)
+#define SJA1110_RX_HEADER_SWITCH_ID(x)		((x) & GENMASK(3, 0))
+
+/* Timestamp format (trailer present) */
+#define SJA1110_RX_HEADER_TRAILER_POS(x)	((x) & GENMASK(11, 0))
+
+#define SJA1110_RX_TRAILER_SWITCH_ID(x)		(((x) & GENMASK(7, 4)) >> 4)
+#define SJA1110_RX_TRAILER_SRC_PORT(x)		((x) & GENMASK(3, 0))
+
+/* Meta frame format (for 2-step TX timestamps) */
+#define SJA1110_RX_HEADER_N_TS(x)		(((x) & GENMASK(8, 4)) >> 4)
+
+/* TX header */
+#define SJA1110_TX_HEADER_UPDATE_TC		BIT(14)
+#define SJA1110_TX_HEADER_TAKE_TS		BIT(13)
+#define SJA1110_TX_HEADER_TAKE_TS_CASC		BIT(12)
+#define SJA1110_TX_HEADER_HAS_TRAILER		BIT(11)
+
+/* Only valid if SJA1110_TX_HEADER_HAS_TRAILER is false */
+#define SJA1110_TX_HEADER_PRIO(x)		(((x) << 7) & GENMASK(10, 7))
+#define SJA1110_TX_HEADER_TSTAMP_ID(x)		((x) & GENMASK(7, 0))
+
+/* Only valid if SJA1110_TX_HEADER_HAS_TRAILER is true */
+#define SJA1110_TX_HEADER_TRAILER_POS(x)	((x) & GENMASK(10, 0))
+
+#define SJA1110_TX_TRAILER_TSTAMP_ID(x)		(((x) << 24) & GENMASK(31, 24))
+#define SJA1110_TX_TRAILER_PRIO(x)		(((x) << 21) & GENMASK(23, 21))
+#define SJA1110_TX_TRAILER_SWITCHID(x)		(((x) << 12) & GENMASK(15, 12))
+#define SJA1110_TX_TRAILER_DESTPORTS(x)		(((x) << 1) & GENMASK(11, 1))
+
+#define SJA1110_META_TSTAMP_SIZE		10
+
+#define SJA1110_HEADER_LEN			4
+#define SJA1110_RX_TRAILER_LEN			13
+#define SJA1110_TX_TRAILER_LEN			4
+#define SJA1110_MAX_PADDING_LEN			15
+
+struct sja1105_tagger_private {
+	struct sja1105_tagger_data data; /* Must be first */
+	/* Protects concurrent access to the meta state machine
+	 * from taggers running on multiple ports on SMP systems
+	 */
+	spinlock_t meta_lock;
+	struct sk_buff *stampable_skb;
+	struct kthread_worker *xmit_worker;
+};
+
+static struct sja1105_tagger_private *
+sja1105_tagger_private(struct dsa_switch *ds)
+{
+	return ds->tagger_data;
+}
+
+/* Similar to is_link_local_ether_addr(hdr->h_dest) but also covers PTP */
+static inline bool sja1105_is_link_local(const struct sk_buff *skb)
+{
+	const struct ethhdr *hdr = eth_hdr(skb);
+	u64 dmac = ether_addr_to_u64(hdr->h_dest);
+
+	if (ntohs(hdr->h_proto) == ETH_P_SJA1105_META)
+		return false;
+	if ((dmac & SJA1105_LINKLOCAL_FILTER_A_MASK) ==
+		    SJA1105_LINKLOCAL_FILTER_A)
+		return true;
+	if ((dmac & SJA1105_LINKLOCAL_FILTER_B_MASK) ==
+		    SJA1105_LINKLOCAL_FILTER_B)
+		return true;
+	return false;
+}
+
+struct sja1105_meta {
+	u64 tstamp;
+	u64 dmac_byte_4;
+	u64 dmac_byte_3;
+	u64 source_port;
+	u64 switch_id;
+};
+
+static void sja1105_meta_unpack(const struct sk_buff *skb,
+				struct sja1105_meta *meta)
+{
+	u8 *buf = skb_mac_header(skb) + ETH_HLEN;
+
+	/* UM10944.pdf section 4.2.17 AVB Parameters:
+	 * Structure of the meta-data follow-up frame.
+	 * It is in network byte order, so there are no quirks
+	 * while unpacking the meta frame.
+	 *
+	 * Also SJA1105 E/T only populates bits 23:0 of the timestamp
+	 * whereas P/Q/R/S does 32 bits. Since the structure is the
+	 * same and the E/T puts zeroes in the high-order byte, use
+	 * a unified unpacking command for both device series.
+	 */
+	packing(buf,     &meta->tstamp,     31, 0, 4, UNPACK, 0);
+	packing(buf + 4, &meta->dmac_byte_3, 7, 0, 1, UNPACK, 0);
+	packing(buf + 5, &meta->dmac_byte_4, 7, 0, 1, UNPACK, 0);
+	packing(buf + 6, &meta->source_port, 7, 0, 1, UNPACK, 0);
+	packing(buf + 7, &meta->switch_id,   7, 0, 1, UNPACK, 0);
+}
+
+static inline bool sja1105_is_meta_frame(const struct sk_buff *skb)
+{
+	const struct ethhdr *hdr = eth_hdr(skb);
+	u64 smac = ether_addr_to_u64(hdr->h_source);
+	u64 dmac = ether_addr_to_u64(hdr->h_dest);
+
+	if (smac != SJA1105_META_SMAC)
+		return false;
+	if (dmac != SJA1105_META_DMAC)
+		return false;
+	if (ntohs(hdr->h_proto) != ETH_P_SJA1105_META)
+		return false;
+	return true;
+}
+
+/* Calls sja1105_port_deferred_xmit in sja1105_main.c */
+static struct sk_buff *sja1105_defer_xmit(struct dsa_port *dp,
+					  struct sk_buff *skb)
+{
+	struct sja1105_tagger_data *tagger_data = sja1105_tagger_data(dp->ds);
+	struct sja1105_tagger_private *priv = sja1105_tagger_private(dp->ds);
+	void (*xmit_work_fn)(struct kthread_work *work);
+	struct sja1105_deferred_xmit_work *xmit_work;
+	struct kthread_worker *xmit_worker;
+
+	xmit_work_fn = tagger_data->xmit_work_fn;
+	xmit_worker = priv->xmit_worker;
+
+	if (!xmit_work_fn || !xmit_worker)
+		return NULL;
+
+	xmit_work = kzalloc(sizeof(*xmit_work), GFP_ATOMIC);
+	if (!xmit_work)
+		return NULL;
+
+	kthread_init_work(&xmit_work->work, xmit_work_fn);
+	/* Increase refcount so the kfree_skb in dsa_slave_xmit
+	 * won't really free the packet.
+	 */
+	xmit_work->dp = dp;
+	xmit_work->skb = skb_get(skb);
+
+	kthread_queue_work(xmit_worker, &xmit_work->work);
+
+	return NULL;
+}
+
+/* Send VLAN tags with a TPID that blends in with whatever VLAN protocol a
+ * bridge spanning ports of this switch might have.
+ */
+static u16 sja1105_xmit_tpid(struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_port *other_dp;
+	u16 proto;
+
+	/* Since VLAN awareness is global, then if this port is VLAN-unaware,
+	 * all ports are. Use the VLAN-unaware TPID used for tag_8021q.
+	 */
+	if (!dsa_port_is_vlan_filtering(dp))
+		return ETH_P_SJA1105;
+
+	/* Port is VLAN-aware, so there is a bridge somewhere (a single one,
+	 * we're sure about that). It may not be on this port though, so we
+	 * need to find it.
+	 */
+	dsa_switch_for_each_port(other_dp, ds) {
+		struct net_device *br = dsa_port_bridge_dev_get(other_dp);
+
+		if (!br)
+			continue;
+
+		/* Error is returned only if CONFIG_BRIDGE_VLAN_FILTERING,
+		 * which seems pointless to handle, as our port cannot become
+		 * VLAN-aware in that case.
+		 */
+		br_vlan_get_proto(br, &proto);
+
+		return proto;
+	}
+
+	WARN_ONCE(1, "Port is VLAN-aware but cannot find associated bridge!\n");
+
+	return ETH_P_SJA1105;
+}
+
+static struct sk_buff *sja1105_imprecise_xmit(struct sk_buff *skb,
+					      struct net_device *netdev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(netdev);
+	unsigned int bridge_num = dsa_port_bridge_num_get(dp);
+	struct net_device *br = dsa_port_bridge_dev_get(dp);
+	u16 tx_vid;
+
+	/* If the port is under a VLAN-aware bridge, just slide the
+	 * VLAN-tagged packet into the FDB and hope for the best.
+	 * This works because we support a single VLAN-aware bridge
+	 * across the entire dst, and its VLANs cannot be shared with
+	 * any standalone port.
+	 */
+	if (br_vlan_enabled(br))
+		return skb;
+
+	/* If the port is under a VLAN-unaware bridge, use an imprecise
+	 * TX VLAN that targets the bridge's entire broadcast domain,
+	 * instead of just the specific port.
+	 */
+	tx_vid = dsa_tag_8021q_bridge_vid(bridge_num);
+
+	return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp), tx_vid);
+}
+
+/* Transform untagged control packets into pvid-tagged control packets so that
+ * all packets sent by this tagger are VLAN-tagged and we can configure the
+ * switch to drop untagged packets coming from the DSA master.
+ */
+static struct sk_buff *sja1105_pvid_tag_control_pkt(struct dsa_port *dp,
+						    struct sk_buff *skb, u8 pcp)
+{
+	__be16 xmit_tpid = htons(sja1105_xmit_tpid(dp));
+	struct vlan_ethhdr *hdr;
+
+	/* If VLAN tag is in hwaccel area, move it to the payload
+	 * to deal with both cases uniformly and to ensure that
+	 * the VLANs are added in the right order.
+	 */
+	if (unlikely(skb_vlan_tag_present(skb))) {
+		skb = __vlan_hwaccel_push_inside(skb);
+		if (!skb)
+			return NULL;
+	}
+
+	hdr = (struct vlan_ethhdr *)skb_mac_header(skb);
+
+	/* If skb is already VLAN-tagged, leave that VLAN ID in place */
+	if (hdr->h_vlan_proto == xmit_tpid)
+		return skb;
+
+	return vlan_insert_tag(skb, xmit_tpid, (pcp << VLAN_PRIO_SHIFT) |
+			       SJA1105_DEFAULT_VLAN);
+}
+
+static struct sk_buff *sja1105_xmit(struct sk_buff *skb,
+				    struct net_device *netdev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(netdev);
+	u16 queue_mapping = skb_get_queue_mapping(skb);
+	u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
+	u16 tx_vid = dsa_tag_8021q_standalone_vid(dp);
+
+	if (skb->offload_fwd_mark)
+		return sja1105_imprecise_xmit(skb, netdev);
+
+	/* Transmitting management traffic does not rely upon switch tagging,
+	 * but instead SPI-installed management routes. Part 2 of this
+	 * is the .port_deferred_xmit driver callback.
+	 */
+	if (unlikely(sja1105_is_link_local(skb))) {
+		skb = sja1105_pvid_tag_control_pkt(dp, skb, pcp);
+		if (!skb)
+			return NULL;
+
+		return sja1105_defer_xmit(dp, skb);
+	}
+
+	return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp),
+			     ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
+}
+
+static struct sk_buff *sja1110_xmit(struct sk_buff *skb,
+				    struct net_device *netdev)
+{
+	struct sk_buff *clone = SJA1105_SKB_CB(skb)->clone;
+	struct dsa_port *dp = dsa_slave_to_port(netdev);
+	u16 queue_mapping = skb_get_queue_mapping(skb);
+	u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
+	u16 tx_vid = dsa_tag_8021q_standalone_vid(dp);
+	__be32 *tx_trailer;
+	__be16 *tx_header;
+	int trailer_pos;
+
+	if (skb->offload_fwd_mark)
+		return sja1105_imprecise_xmit(skb, netdev);
+
+	/* Transmitting control packets is done using in-band control
+	 * extensions, while data packets are transmitted using
+	 * tag_8021q TX VLANs.
+	 */
+	if (likely(!sja1105_is_link_local(skb)))
+		return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp),
+				     ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
+
+	skb = sja1105_pvid_tag_control_pkt(dp, skb, pcp);
+	if (!skb)
+		return NULL;
+
+	skb_push(skb, SJA1110_HEADER_LEN);
+
+	dsa_alloc_etype_header(skb, SJA1110_HEADER_LEN);
+
+	trailer_pos = skb->len;
+
+	tx_header = dsa_etype_header_pos_tx(skb);
+	tx_trailer = skb_put(skb, SJA1110_TX_TRAILER_LEN);
+
+	tx_header[0] = htons(ETH_P_SJA1110);
+	tx_header[1] = htons(SJA1110_HEADER_HOST_TO_SWITCH |
+			     SJA1110_TX_HEADER_HAS_TRAILER |
+			     SJA1110_TX_HEADER_TRAILER_POS(trailer_pos));
+	*tx_trailer = cpu_to_be32(SJA1110_TX_TRAILER_PRIO(pcp) |
+				  SJA1110_TX_TRAILER_SWITCHID(dp->ds->index) |
+				  SJA1110_TX_TRAILER_DESTPORTS(BIT(dp->index)));
+	if (clone) {
+		u8 ts_id = SJA1105_SKB_CB(clone)->ts_id;
+
+		tx_header[1] |= htons(SJA1110_TX_HEADER_TAKE_TS);
+		*tx_trailer |= cpu_to_be32(SJA1110_TX_TRAILER_TSTAMP_ID(ts_id));
+	}
+
+	return skb;
+}
+
+static void sja1105_transfer_meta(struct sk_buff *skb,
+				  const struct sja1105_meta *meta)
+{
+	struct ethhdr *hdr = eth_hdr(skb);
+
+	hdr->h_dest[3] = meta->dmac_byte_3;
+	hdr->h_dest[4] = meta->dmac_byte_4;
+	SJA1105_SKB_CB(skb)->tstamp = meta->tstamp;
+}
+
+/* This is a simple state machine which follows the hardware mechanism of
+ * generating RX timestamps:
+ *
+ * After each timestampable skb (all traffic for which send_meta1 and
+ * send_meta0 is true, aka all MAC-filtered link-local traffic) a meta frame
+ * containing a partial timestamp is immediately generated by the switch and
+ * sent as a follow-up to the link-local frame on the CPU port.
+ *
+ * The meta frames have no unique identifier (such as sequence number) by which
+ * one may pair them to the correct timestampable frame.
+ * Instead, the switch has internal logic that ensures no frames are sent on
+ * the CPU port between a link-local timestampable frame and its corresponding
+ * meta follow-up. It also ensures strict ordering between ports (lower ports
+ * have higher priority towards the CPU port). For this reason, a per-port
+ * data structure is not needed/desirable.
+ *
+ * This function pairs the link-local frame with its partial timestamp from the
+ * meta follow-up frame. The full timestamp will be reconstructed later in a
+ * work queue.
+ */
+static struct sk_buff
+*sja1105_rcv_meta_state_machine(struct sk_buff *skb,
+				struct sja1105_meta *meta,
+				bool is_link_local,
+				bool is_meta)
+{
+	/* Step 1: A timestampable frame was received.
+	 * Buffer it until we get its meta frame.
+	 */
+	if (is_link_local) {
+		struct dsa_port *dp = dsa_slave_to_port(skb->dev);
+		struct sja1105_tagger_private *priv;
+		struct dsa_switch *ds = dp->ds;
+
+		priv = sja1105_tagger_private(ds);
+
+		spin_lock(&priv->meta_lock);
+		/* Was this a link-local frame instead of the meta
+		 * that we were expecting?
+		 */
+		if (priv->stampable_skb) {
+			dev_err_ratelimited(ds->dev,
+					    "Expected meta frame, is %12llx "
+					    "in the DSA master multicast filter?\n",
+					    SJA1105_META_DMAC);
+			kfree_skb(priv->stampable_skb);
+		}
+
+		/* Hold a reference to avoid dsa_switch_rcv
+		 * from freeing the skb.
+		 */
+		priv->stampable_skb = skb_get(skb);
+		spin_unlock(&priv->meta_lock);
+
+		/* Tell DSA we got nothing */
+		return NULL;
+
+	/* Step 2: The meta frame arrived.
+	 * Time to take the stampable skb out of the closet, annotate it
+	 * with the partial timestamp, and pretend that we received it
+	 * just now (basically masquerade the buffered frame as the meta
+	 * frame, which serves no further purpose).
+	 */
+	} else if (is_meta) {
+		struct dsa_port *dp = dsa_slave_to_port(skb->dev);
+		struct sja1105_tagger_private *priv;
+		struct dsa_switch *ds = dp->ds;
+		struct sk_buff *stampable_skb;
+
+		priv = sja1105_tagger_private(ds);
+
+		spin_lock(&priv->meta_lock);
+
+		stampable_skb = priv->stampable_skb;
+		priv->stampable_skb = NULL;
+
+		/* Was this a meta frame instead of the link-local
+		 * that we were expecting?
+		 */
+		if (!stampable_skb) {
+			dev_err_ratelimited(ds->dev,
+					    "Unexpected meta frame\n");
+			spin_unlock(&priv->meta_lock);
+			return NULL;
+		}
+
+		if (stampable_skb->dev != skb->dev) {
+			dev_err_ratelimited(ds->dev,
+					    "Meta frame on wrong port\n");
+			spin_unlock(&priv->meta_lock);
+			return NULL;
+		}
+
+		/* Free the meta frame and give DSA the buffered stampable_skb
+		 * for further processing up the network stack.
+		 */
+		kfree_skb(skb);
+		skb = stampable_skb;
+		sja1105_transfer_meta(skb, meta);
+
+		spin_unlock(&priv->meta_lock);
+	}
+
+	return skb;
+}
+
+static bool sja1105_skb_has_tag_8021q(const struct sk_buff *skb)
+{
+	u16 tpid = ntohs(eth_hdr(skb)->h_proto);
+
+	return tpid == ETH_P_SJA1105 || tpid == ETH_P_8021Q ||
+	       skb_vlan_tag_present(skb);
+}
+
+static bool sja1110_skb_has_inband_control_extension(const struct sk_buff *skb)
+{
+	return ntohs(eth_hdr(skb)->h_proto) == ETH_P_SJA1110;
+}
+
+/* If the VLAN in the packet is a tag_8021q one, set @source_port and
+ * @switch_id and strip the header. Otherwise set @vid and keep it in the
+ * packet.
+ */
+static void sja1105_vlan_rcv(struct sk_buff *skb, int *source_port,
+			     int *switch_id, int *vbid, u16 *vid)
+{
+	struct vlan_ethhdr *hdr = (struct vlan_ethhdr *)skb_mac_header(skb);
+	u16 vlan_tci;
+
+	if (skb_vlan_tag_present(skb))
+		vlan_tci = skb_vlan_tag_get(skb);
+	else
+		vlan_tci = ntohs(hdr->h_vlan_TCI);
+
+	if (vid_is_dsa_8021q(vlan_tci & VLAN_VID_MASK))
+		return dsa_8021q_rcv(skb, source_port, switch_id, vbid);
+
+	/* Try our best with imprecise RX */
+	*vid = vlan_tci & VLAN_VID_MASK;
+}
+
+static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
+				   struct net_device *netdev)
+{
+	int source_port = -1, switch_id = -1, vbid = -1;
+	struct sja1105_meta meta = {0};
+	struct ethhdr *hdr;
+	bool is_link_local;
+	bool is_meta;
+	u16 vid;
+
+	hdr = eth_hdr(skb);
+	is_link_local = sja1105_is_link_local(skb);
+	is_meta = sja1105_is_meta_frame(skb);
+
+	if (is_link_local) {
+		/* Management traffic path. Switch embeds the switch ID and
+		 * port ID into bytes of the destination MAC, courtesy of
+		 * the incl_srcpt options.
+		 */
+		source_port = hdr->h_dest[3];
+		switch_id = hdr->h_dest[4];
+	} else if (is_meta) {
+		sja1105_meta_unpack(skb, &meta);
+		source_port = meta.source_port;
+		switch_id = meta.switch_id;
+	}
+
+	/* Normal data plane traffic and link-local frames are tagged with
+	 * a tag_8021q VLAN which we have to strip
+	 */
+	if (sja1105_skb_has_tag_8021q(skb)) {
+		int tmp_source_port = -1, tmp_switch_id = -1;
+
+		sja1105_vlan_rcv(skb, &tmp_source_port, &tmp_switch_id, &vbid,
+				 &vid);
+		/* Preserve the source information from the INCL_SRCPT option,
+		 * if available. This allows us to not overwrite a valid source
+		 * port and switch ID with zeroes when receiving link-local
+		 * frames from a VLAN-unaware bridged port (non-zero vbid) or a
+		 * VLAN-aware bridged port (non-zero vid). Furthermore, the
+		 * tag_8021q source port information is only of trust when the
+		 * vbid is 0 (precise port). Otherwise, tmp_source_port and
+		 * tmp_switch_id will be zeroes.
+		 */
+		if (vbid == 0 && source_port == -1)
+			source_port = tmp_source_port;
+		if (vbid == 0 && switch_id == -1)
+			switch_id = tmp_switch_id;
+	} else if (source_port == -1 && switch_id == -1) {
+		/* Packets with no source information have no chance of
+		 * getting accepted, drop them straight away.
+		 */
+		return NULL;
+	}
+
+	if (source_port != -1 && switch_id != -1)
+		skb->dev = dsa_master_find_slave(netdev, switch_id, source_port);
+	else if (vbid >= 1)
+		skb->dev = dsa_tag_8021q_find_port_by_vbid(netdev, vbid);
+	else
+		skb->dev = dsa_find_designated_bridge_port_by_vid(netdev, vid);
+	if (!skb->dev) {
+		netdev_warn(netdev, "Couldn't decode source port\n");
+		return NULL;
+	}
+
+	if (!is_link_local)
+		dsa_default_offload_fwd_mark(skb);
+
+	return sja1105_rcv_meta_state_machine(skb, &meta, is_link_local,
+					      is_meta);
+}
+
+static struct sk_buff *sja1110_rcv_meta(struct sk_buff *skb, u16 rx_header)
+{
+	u8 *buf = dsa_etype_header_pos_rx(skb) + SJA1110_HEADER_LEN;
+	int switch_id = SJA1110_RX_HEADER_SWITCH_ID(rx_header);
+	int n_ts = SJA1110_RX_HEADER_N_TS(rx_header);
+	struct sja1105_tagger_data *tagger_data;
+	struct net_device *master = skb->dev;
+	struct dsa_port *cpu_dp;
+	struct dsa_switch *ds;
+	int i;
+
+	cpu_dp = master->dsa_ptr;
+	ds = dsa_switch_find(cpu_dp->dst->index, switch_id);
+	if (!ds) {
+		net_err_ratelimited("%s: cannot find switch id %d\n",
+				    master->name, switch_id);
+		return NULL;
+	}
+
+	tagger_data = sja1105_tagger_data(ds);
+	if (!tagger_data->meta_tstamp_handler)
+		return NULL;
+
+	for (i = 0; i <= n_ts; i++) {
+		u8 ts_id, source_port, dir;
+		u64 tstamp;
+
+		ts_id = buf[0];
+		source_port = (buf[1] & GENMASK(7, 4)) >> 4;
+		dir = (buf[1] & BIT(3)) >> 3;
+		tstamp = be64_to_cpu(*(__be64 *)(buf + 2));
+
+		tagger_data->meta_tstamp_handler(ds, source_port, ts_id, dir,
+						 tstamp);
+
+		buf += SJA1110_META_TSTAMP_SIZE;
+	}
+
+	/* Discard the meta frame, we've consumed the timestamps it contained */
+	return NULL;
+}
+
+static struct sk_buff *sja1110_rcv_inband_control_extension(struct sk_buff *skb,
+							    int *source_port,
+							    int *switch_id,
+							    bool *host_only)
+{
+	u16 rx_header;
+
+	if (unlikely(!pskb_may_pull(skb, SJA1110_HEADER_LEN)))
+		return NULL;
+
+	/* skb->data points to skb_mac_header(skb) + ETH_HLEN, which is exactly
+	 * what we need because the caller has checked the EtherType (which is
+	 * located 2 bytes back) and we just need a pointer to the header that
+	 * comes afterwards.
+	 */
+	rx_header = ntohs(*(__be16 *)skb->data);
+
+	if (rx_header & SJA1110_RX_HEADER_HOST_ONLY)
+		*host_only = true;
+
+	if (rx_header & SJA1110_RX_HEADER_IS_METADATA)
+		return sja1110_rcv_meta(skb, rx_header);
+
+	/* Timestamp frame, we have a trailer */
+	if (rx_header & SJA1110_RX_HEADER_HAS_TRAILER) {
+		int start_of_padding = SJA1110_RX_HEADER_TRAILER_POS(rx_header);
+		u8 *rx_trailer = skb_tail_pointer(skb) - SJA1110_RX_TRAILER_LEN;
+		u64 *tstamp = &SJA1105_SKB_CB(skb)->tstamp;
+		u8 last_byte = rx_trailer[12];
+
+		/* The timestamp is unaligned, so we need to use packing()
+		 * to get it
+		 */
+		packing(rx_trailer, tstamp, 63, 0, 8, UNPACK, 0);
+
+		*source_port = SJA1110_RX_TRAILER_SRC_PORT(last_byte);
+		*switch_id = SJA1110_RX_TRAILER_SWITCH_ID(last_byte);
+
+		/* skb->len counts from skb->data, while start_of_padding
+		 * counts from the destination MAC address. Right now skb->data
+		 * is still as set by the DSA master, so to trim away the
+		 * padding and trailer we need to account for the fact that
+		 * skb->data points to skb_mac_header(skb) + ETH_HLEN.
+		 */
+		if (pskb_trim_rcsum(skb, start_of_padding - ETH_HLEN))
+			return NULL;
+	/* Trap-to-host frame, no timestamp trailer */
+	} else {
+		*source_port = SJA1110_RX_HEADER_SRC_PORT(rx_header);
+		*switch_id = SJA1110_RX_HEADER_SWITCH_ID(rx_header);
+	}
+
+	/* Advance skb->data past the DSA header */
+	skb_pull_rcsum(skb, SJA1110_HEADER_LEN);
+
+	dsa_strip_etype_header(skb, SJA1110_HEADER_LEN);
+
+	/* With skb->data in its final place, update the MAC header
+	 * so that eth_hdr() continues to works properly.
+	 */
+	skb_set_mac_header(skb, -ETH_HLEN);
+
+	return skb;
+}
+
+static struct sk_buff *sja1110_rcv(struct sk_buff *skb,
+				   struct net_device *netdev)
+{
+	int source_port = -1, switch_id = -1, vbid = -1;
+	bool host_only = false;
+	u16 vid = 0;
+
+	if (sja1110_skb_has_inband_control_extension(skb)) {
+		skb = sja1110_rcv_inband_control_extension(skb, &source_port,
+							   &switch_id,
+							   &host_only);
+		if (!skb)
+			return NULL;
+	}
+
+	/* Packets with in-band control extensions might still have RX VLANs */
+	if (likely(sja1105_skb_has_tag_8021q(skb)))
+		sja1105_vlan_rcv(skb, &source_port, &switch_id, &vbid, &vid);
+
+	if (vbid >= 1)
+		skb->dev = dsa_tag_8021q_find_port_by_vbid(netdev, vbid);
+	else if (source_port == -1 || switch_id == -1)
+		skb->dev = dsa_find_designated_bridge_port_by_vid(netdev, vid);
+	else
+		skb->dev = dsa_master_find_slave(netdev, switch_id, source_port);
+	if (!skb->dev) {
+		netdev_warn(netdev, "Couldn't decode source port\n");
+		return NULL;
+	}
+
+	if (!host_only)
+		dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+
+static void sja1105_flow_dissect(const struct sk_buff *skb, __be16 *proto,
+				 int *offset)
+{
+	/* No tag added for management frames, all ok */
+	if (unlikely(sja1105_is_link_local(skb)))
+		return;
+
+	dsa_tag_generic_flow_dissect(skb, proto, offset);
+}
+
+static void sja1110_flow_dissect(const struct sk_buff *skb, __be16 *proto,
+				 int *offset)
+{
+	/* Management frames have 2 DSA tags on RX, so the needed_headroom we
+	 * declared is fine for the generic dissector adjustment procedure.
+	 */
+	if (unlikely(sja1105_is_link_local(skb)))
+		return dsa_tag_generic_flow_dissect(skb, proto, offset);
+
+	/* For the rest, there is a single DSA tag, the tag_8021q one */
+	*offset = VLAN_HLEN;
+	*proto = ((__be16 *)skb->data)[(VLAN_HLEN / 2) - 1];
+}
+
+static void sja1105_disconnect(struct dsa_switch *ds)
+{
+	struct sja1105_tagger_private *priv = ds->tagger_data;
+
+	kthread_destroy_worker(priv->xmit_worker);
+	kfree(priv);
+	ds->tagger_data = NULL;
+}
+
+static int sja1105_connect(struct dsa_switch *ds)
+{
+	struct sja1105_tagger_private *priv;
+	struct kthread_worker *xmit_worker;
+	int err;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	spin_lock_init(&priv->meta_lock);
+
+	xmit_worker = kthread_create_worker(0, "dsa%d:%d_xmit",
+					    ds->dst->index, ds->index);
+	if (IS_ERR(xmit_worker)) {
+		err = PTR_ERR(xmit_worker);
+		kfree(priv);
+		return err;
+	}
+
+	priv->xmit_worker = xmit_worker;
+	ds->tagger_data = priv;
+
+	return 0;
+}
+
+static const struct dsa_device_ops sja1105_netdev_ops = {
+	.name = "sja1105",
+	.proto = DSA_TAG_PROTO_SJA1105,
+	.xmit = sja1105_xmit,
+	.rcv = sja1105_rcv,
+	.connect = sja1105_connect,
+	.disconnect = sja1105_disconnect,
+	.needed_headroom = VLAN_HLEN,
+	.flow_dissect = sja1105_flow_dissect,
+	.promisc_on_master = true,
+};
+
+DSA_TAG_DRIVER(sja1105_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1105);
+
+static const struct dsa_device_ops sja1110_netdev_ops = {
+	.name = "sja1110",
+	.proto = DSA_TAG_PROTO_SJA1110,
+	.xmit = sja1110_xmit,
+	.rcv = sja1110_rcv,
+	.connect = sja1105_connect,
+	.disconnect = sja1105_disconnect,
+	.flow_dissect = sja1110_flow_dissect,
+	.needed_headroom = SJA1110_HEADER_LEN + VLAN_HLEN,
+	.needed_tailroom = SJA1110_RX_TRAILER_LEN + SJA1110_MAX_PADDING_LEN,
+};
+
+DSA_TAG_DRIVER(sja1110_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1110);
+
+static struct dsa_tag_driver *sja1105_tag_driver_array[] = {
+	&DSA_TAG_DRIVER_NAME(sja1105_netdev_ops),
+	&DSA_TAG_DRIVER_NAME(sja1110_netdev_ops),
+};
+
+module_dsa_tag_drivers(sja1105_tag_driver_array);
+
+MODULE_LICENSE("GPL v2");
diff --git a/net/dsa/tag_trailer.c b/net/dsa/tag_trailer.c
new file mode 100644
index 000000000..5749ba85c
--- /dev/null
+++ b/net/dsa/tag_trailer.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * net/dsa/tag_trailer.c - Trailer tag format handling
+ * Copyright (c) 2008-2009 Marvell Semiconductor
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "dsa_priv.h"
+
+static struct sk_buff *trailer_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u8 *trailer;
+
+	trailer = skb_put(skb, 4);
+	trailer[0] = 0x80;
+	trailer[1] = 1 << dp->index;
+	trailer[2] = 0x10;
+	trailer[3] = 0x00;
+
+	return skb;
+}
+
+static struct sk_buff *trailer_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	u8 *trailer;
+	int source_port;
+
+	if (skb_linearize(skb))
+		return NULL;
+
+	trailer = skb_tail_pointer(skb) - 4;
+	if (trailer[0] != 0x80 || (trailer[1] & 0xf8) != 0x00 ||
+	    (trailer[2] & 0xef) != 0x00 || trailer[3] != 0x00)
+		return NULL;
+
+	source_port = trailer[1] & 7;
+
+	skb->dev = dsa_master_find_slave(dev, 0, source_port);
+	if (!skb->dev)
+		return NULL;
+
+	if (pskb_trim_rcsum(skb, skb->len - 4))
+		return NULL;
+
+	return skb;
+}
+
+static const struct dsa_device_ops trailer_netdev_ops = {
+	.name	= "trailer",
+	.proto	= DSA_TAG_PROTO_TRAILER,
+	.xmit	= trailer_xmit,
+	.rcv	= trailer_rcv,
+	.needed_tailroom = 4,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_TRAILER);
+
+module_dsa_tag_driver(trailer_netdev_ops);
diff --git a/net/dsa/tag_xrs700x.c b/net/dsa/tag_xrs700x.c
new file mode 100644
index 000000000..ff442b8af
--- /dev/null
+++ b/net/dsa/tag_xrs700x.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * XRS700x tag format handling
+ * Copyright (c) 2008-2009 Marvell Semiconductor
+ * Copyright (c) 2020 NovaTech LLC
+ */
+
+#include <linux/bitops.h>
+
+#include "dsa_priv.h"
+
+static struct sk_buff *xrs700x_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_port *partner, *dp = dsa_slave_to_port(dev);
+	u8 *trailer;
+
+	trailer = skb_put(skb, 1);
+	trailer[0] = BIT(dp->index);
+
+	if (dp->hsr_dev)
+		dsa_hsr_foreach_port(partner, dp->ds, dp->hsr_dev)
+			if (partner != dp)
+				trailer[0] |= BIT(partner->index);
+
+	return skb;
+}
+
+static struct sk_buff *xrs700x_rcv(struct sk_buff *skb, struct net_device *dev)
+{
+	int source_port;
+	u8 *trailer;
+
+	trailer = skb_tail_pointer(skb) - 1;
+
+	source_port = ffs((int)trailer[0]) - 1;
+
+	if (source_port < 0)
+		return NULL;
+
+	skb->dev = dsa_master_find_slave(dev, 0, source_port);
+	if (!skb->dev)
+		return NULL;
+
+	if (pskb_trim_rcsum(skb, skb->len - 1))
+		return NULL;
+
+	/* Frame is forwarded by hardware, don't forward in software. */
+	dsa_default_offload_fwd_mark(skb);
+
+	return skb;
+}
+
+static const struct dsa_device_ops xrs700x_netdev_ops = {
+	.name	= "xrs700x",
+	.proto	= DSA_TAG_PROTO_XRS700X,
+	.xmit	= xrs700x_xmit,
+	.rcv	= xrs700x_rcv,
+	.needed_tailroom = 1,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_XRS700X);
+
+module_dsa_tag_driver(xrs700x_netdev_ops);