Adding upstream version 5.10.209.upstream/5.10.209

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

23 files changed, 8413 insertions, 0 deletions

diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
new file mode 100644
index 000000000..1f9b9b110
--- /dev/null
+++ b/net/dsa/Kconfig
@@ -0,0 +1,131 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config HAVE_NET_DSA
+	def_bool y
+	depends on INET && NETDEVICES && !S390
+
+# Drivers must select NET_DSA and the appropriate tagging format
+
+menuconfig NET_DSA
+	tristate "Distributed Switch Architecture"
+	depends on HAVE_NET_DSA
+	depends on BRIDGE || BRIDGE=n
+	select GRO_CELLS
+	select NET_SWITCHDEV
+	select PHYLINK
+	select NET_DEVLINK
+	help
+	  Say Y if you want to enable support for the hardware switches supported
+	  by the Distributed Switch Architecture.
+
+if NET_DSA
+
+# tagging formats
+config NET_DSA_TAG_8021Q
+	tristate
+	select VLAN_8021Q
+	help
+	  Unlike the other tagging protocols, the 802.1Q config option simply
+	  provides helpers for other tagging implementations that might rely on
+	  VLAN in one way or another. It is not a complete solution.
+
+	  Drivers which use these helpers should select this as dependency.
+
+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_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_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
+	tristate "Tag driver for Marvell switches using DSA headers"
+	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"
+	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 8795/9477/9893 families of switches"
+	help
+	  Say Y if you want to enable support for tagging frames for the
+	  Microchip 8795/9477/9893 families of 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_OCELOT
+	tristate "Tag driver for Ocelot family of switches"
+	select PACKING
+	help
+	  Say Y or M if you want to enable support for tagging frames for the
+	  Ocelot switches (VSC7511, VSC7512, VSC7513, VSC7514, VSC9959).
+
+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_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 NET_DSA_TAG_8021Q
+	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.
+
+endif
diff --git a/net/dsa/Makefile b/net/dsa/Makefile
new file mode 100644
index 000000000..4f47b2025
--- /dev/null
+++ b/net/dsa/Makefile
@@ -0,0 +1,20 @@
+# SPDX-License-Identifier: GPL-2.0
+# the core
+obj-$(CONFIG_NET_DSA) += dsa_core.o
+dsa_core-y += dsa.o dsa2.o master.o port.o slave.o switch.o
+
+# tagging formats
+obj-$(CONFIG_NET_DSA_TAG_8021Q) += tag_8021q.o
+obj-$(CONFIG_NET_DSA_TAG_AR9331) += tag_ar9331.o
+obj-$(CONFIG_NET_DSA_TAG_BRCM_COMMON) += tag_brcm.o
+obj-$(CONFIG_NET_DSA_TAG_DSA) += tag_dsa.o
+obj-$(CONFIG_NET_DSA_TAG_EDSA) += tag_edsa.o
+obj-$(CONFIG_NET_DSA_TAG_GSWIP) += tag_gswip.o
+obj-$(CONFIG_NET_DSA_TAG_KSZ) += tag_ksz.o
+obj-$(CONFIG_NET_DSA_TAG_RTL4_A) += tag_rtl4_a.o
+obj-$(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-$(CONFIG_NET_DSA_TAG_QCA) += tag_qca.o
+obj-$(CONFIG_NET_DSA_TAG_SJA1105) += tag_sja1105.o
+obj-$(CONFIG_NET_DSA_TAG_TRAILER) += tag_trailer.o
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
new file mode 100644
index 000000000..2131bf2b3
--- /dev/null
+++ b/net/dsa/dsa.c
@@ -0,0 +1,495 @@
+// 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/platform_device.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/of_mdio.h>
+#include <linux/of_platform.h>
+#include <linux/of_net.h>
+#include <linux/netdevice.h>
+#include <linux/sysfs.h>
+#include <linux/phy_fixed.h>
+#include <linux/ptp_classify.h>
+#include <linux/etherdevice.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;
+};
+
+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 pcpu_sw_netstats *s;
+	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, pt);
+	if (!nskb) {
+		kfree_skb(skb);
+		return 0;
+	}
+
+	skb = nskb;
+	p = netdev_priv(skb->dev);
+	skb_push(skb, ETH_HLEN);
+	skb->pkt_type = PACKET_HOST;
+	skb->protocol = eth_type_trans(skb, 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;
+	}
+
+	s = this_cpu_ptr(p->stats64);
+	u64_stats_update_begin(&s->syncp);
+	s->rx_packets++;
+	s->rx_bytes += skb->len;
+	u64_stats_update_end(&s->syncp);
+
+	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_is_port_initialized(struct dsa_switch *ds, int p)
+{
+	const struct dsa_port *dp = dsa_to_port(ds, p);
+
+	return dp->type == DSA_PORT_TYPE_USER && dp->slave;
+}
+
+int dsa_switch_suspend(struct dsa_switch *ds)
+{
+	int i, ret = 0;
+
+	/* Suspend slave network devices */
+	for (i = 0; i < ds->num_ports; i++) {
+		if (!dsa_is_port_initialized(ds, i))
+			continue;
+
+		ret = dsa_slave_suspend(dsa_to_port(ds, i)->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)
+{
+	int i, ret = 0;
+
+	if (ds->ops->resume)
+		ret = ds->ops->resume(ds);
+
+	if (ret)
+		return ret;
+
+	/* Resume slave network devices */
+	for (i = 0; i < ds->num_ports; i++) {
+		if (!dsa_is_port_initialized(ds, i))
+			continue;
+
+		ret = dsa_slave_resume(dsa_to_port(ds, i)->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);
+}
+
+static ATOMIC_NOTIFIER_HEAD(dsa_notif_chain);
+
+int register_dsa_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_register(&dsa_notif_chain, nb);
+}
+EXPORT_SYMBOL_GPL(register_dsa_notifier);
+
+int unregister_dsa_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_unregister(&dsa_notif_chain, nb);
+}
+EXPORT_SYMBOL_GPL(unregister_dsa_notifier);
+
+int call_dsa_notifiers(unsigned long val, struct net_device *dev,
+		       struct dsa_notifier_info *info)
+{
+	info->dev = dev;
+	return atomic_notifier_call_chain(&dsa_notif_chain, val, info);
+}
+EXPORT_SYMBOL_GPL(call_dsa_notifiers);
+
+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, NULL);
+}
+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);
+
+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);
+
+	return 0;
+
+register_notifier_fail:
+	destroy_workqueue(dsa_owq);
+
+	return rc;
+}
+module_init(dsa_init_module);
+
+static void __exit dsa_cleanup_module(void)
+{
+	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..f543fca6d
--- /dev/null
+++ b/net/dsa/dsa2.c
@@ -0,0 +1,1027 @@
+// 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_net.h>
+#include <net/devlink.h>
+
+#include "dsa_priv.h"
+
+static DEFINE_MUTEX(dsa2_mutex);
+LIST_HEAD(dsa_tree_list);
+
+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)
+{
+	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 bool dsa_port_is_dsa(struct dsa_port *port)
+{
+	return port->type == DSA_PORT_TYPE_DSA;
+}
+
+static bool dsa_port_is_cpu(struct dsa_port *port)
+{
+	return port->type == DSA_PORT_TYPE_CPU;
+}
+
+static bool dsa_port_is_user(struct dsa_port *dp)
+{
+	return dp->type == DSA_PORT_TYPE_USER;
+}
+
+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;
+}
+
+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;
+	}
+
+	/* Assign the default CPU port to all ports of the fabric */
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dsa_port_is_user(dp) || dsa_port_is_dsa(dp))
+			dp->cpu_dp = cpu_dp;
+
+	return 0;
+}
+
+static void dsa_tree_teardown_default_cpu(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_setup(struct dsa_port *dp)
+{
+	struct devlink_port *dlp = &dp->devlink_port;
+	bool dsa_port_link_registered = false;
+	bool dsa_port_enabled = false;
+	int err = 0;
+
+	if (dp->setup)
+		return 0;
+
+	switch (dp->type) {
+	case DSA_PORT_TYPE_UNUSED:
+		dsa_port_disable(dp);
+		break;
+	case DSA_PORT_TYPE_CPU:
+		err = dsa_port_link_register_of(dp);
+		if (err)
+			break;
+		dsa_port_link_registered = true;
+
+		err = dsa_port_enable(dp, NULL);
+		if (err)
+			break;
+		dsa_port_enabled = true;
+
+		break;
+	case DSA_PORT_TYPE_DSA:
+		err = dsa_port_link_register_of(dp);
+		if (err)
+			break;
+		dsa_port_link_registered = true;
+
+		err = dsa_port_enable(dp, NULL);
+		if (err)
+			break;
+		dsa_port_enabled = true;
+
+		break;
+	case DSA_PORT_TYPE_USER:
+		dp->mac = of_get_mac_address(dp->dn);
+		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_port_link_unregister_of(dp);
+	if (err)
+		return err;
+
+	dp->setup = true;
+
+	return 0;
+}
+
+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;
+	const unsigned char *id;
+	unsigned char len;
+	int 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;
+	memset(dlp, 0, sizeof(*dlp));
+
+	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)
+		dp->devlink_port_setup = true;
+
+	return err;
+}
+
+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);
+		dsa_tag_driver_put(dp->tag_ops);
+		dsa_port_link_unregister_of(dp);
+		break;
+	case DSA_PORT_TYPE_DSA:
+		dsa_port_disable(dp);
+		dsa_port_link_unregister_of(dp);
+		break;
+	case DSA_PORT_TYPE_USER:
+		if (dp->slave) {
+			dsa_slave_destroy(dp->slave);
+			dp->slave = NULL;
+		}
+		break;
+	}
+
+	dp->setup = false;
+}
+
+static void dsa_port_devlink_teardown(struct dsa_port *dp)
+{
+	struct devlink_port *dlp = &dp->devlink_port;
+
+	if (dp->devlink_port_setup)
+		devlink_port_unregister(dlp);
+	dp->devlink_port_setup = false;
+}
+
+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 const struct devlink_ops dsa_devlink_ops = {
+	.info_get = dsa_devlink_info_get,
+};
+
+static int dsa_switch_setup(struct dsa_switch *ds)
+{
+	struct dsa_devlink_priv *dl_priv;
+	struct dsa_port *dp;
+	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));
+	if (!ds->devlink)
+		return -ENOMEM;
+	dl_priv = devlink_priv(ds->devlink);
+	dl_priv->ds = ds;
+
+	err = devlink_register(ds->devlink, ds->dev);
+	if (err)
+		goto free_devlink;
+
+	/* Setup devlink port instances now, so that the switch
+	 * setup() can register regions etc, against the ports
+	 */
+	list_for_each_entry(dp, &ds->dst->ports, list) {
+		if (dp->ds == ds) {
+			err = dsa_port_devlink_setup(dp);
+			if (err)
+				goto unregister_devlink_ports;
+		}
+	}
+
+	err = dsa_switch_register_notifier(ds);
+	if (err)
+		goto unregister_devlink_ports;
+
+	err = ds->ops->setup(ds);
+	if (err < 0)
+		goto unregister_notifier;
+
+	devlink_params_publish(ds->devlink);
+
+	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);
+
+		err = mdiobus_register(ds->slave_mii_bus);
+		if (err < 0)
+			goto free_slave_mii_bus;
+	}
+
+	ds->setup = true;
+
+	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);
+unregister_devlink_ports:
+	list_for_each_entry(dp, &ds->dst->ports, list)
+		if (dp->ds == ds)
+			dsa_port_devlink_teardown(dp);
+	devlink_unregister(ds->devlink);
+free_devlink:
+	devlink_free(ds->devlink);
+	ds->devlink = NULL;
+
+	return err;
+}
+
+static void dsa_switch_teardown(struct dsa_switch *ds)
+{
+	struct dsa_port *dp;
+
+	if (!ds->setup)
+		return;
+
+	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_unregister_notifier(ds);
+
+	if (ds->ops->teardown)
+		ds->ops->teardown(ds);
+
+	if (ds->devlink) {
+		list_for_each_entry(dp, &ds->dst->ports, list)
+			if (dp->ds == ds)
+				dsa_port_devlink_teardown(dp);
+		devlink_unregister(ds->devlink);
+		devlink_free(ds->devlink);
+		ds->devlink = NULL;
+	}
+
+	ds->setup = false;
+}
+
+static int dsa_tree_setup_switches(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *dp;
+	int err;
+
+	list_for_each_entry(dp, &dst->ports, list) {
+		err = dsa_switch_setup(dp->ds);
+		if (err)
+			goto teardown;
+	}
+
+	list_for_each_entry(dp, &dst->ports, list) {
+		err = dsa_port_setup(dp);
+		if (err) {
+			dsa_port_devlink_teardown(dp);
+			dp->type = DSA_PORT_TYPE_UNUSED;
+			err = dsa_port_devlink_setup(dp);
+			if (err)
+				goto teardown;
+			continue;
+		}
+	}
+
+	return 0;
+
+teardown:
+	list_for_each_entry(dp, &dst->ports, list)
+		dsa_port_teardown(dp);
+
+	list_for_each_entry(dp, &dst->ports, list)
+		dsa_switch_teardown(dp->ds);
+
+	return err;
+}
+
+static void dsa_tree_teardown_switches(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		dsa_port_teardown(dp);
+
+	list_for_each_entry(dp, &dst->ports, list)
+		dsa_switch_teardown(dp->ds);
+}
+
+static int dsa_tree_setup_master(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *dp;
+	int err;
+
+	list_for_each_entry(dp, &dst->ports, list) {
+		if (dsa_port_is_cpu(dp)) {
+			err = dsa_master_setup(dp->master, dp);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static void dsa_tree_teardown_master(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dsa_port_is_cpu(dp))
+			dsa_master_teardown(dp->master);
+}
+
+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_default_cpu(dst);
+	if (err)
+		return err;
+
+	err = dsa_tree_setup_switches(dst);
+	if (err)
+		goto teardown_default_cpu;
+
+	err = dsa_tree_setup_master(dst);
+	if (err)
+		goto teardown_switches;
+
+	dst->setup = true;
+
+	pr_info("DSA: tree %d setup\n", dst->index);
+
+	return 0;
+
+teardown_switches:
+	dsa_tree_teardown_switches(dst);
+teardown_default_cpu:
+	dsa_tree_teardown_default_cpu(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_master(dst);
+
+	dsa_tree_teardown_switches(dst);
+
+	dsa_tree_teardown_default_cpu(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 struct dsa_port *dsa_port_touch(struct dsa_switch *ds, int index)
+{
+	struct dsa_switch_tree *dst = ds->dst;
+	struct dsa_port *dp;
+
+	list_for_each_entry(dp, &dst->ports, list)
+		if (dp->ds == ds && dp->index == index)
+			return dp;
+
+	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
+	if (!dp)
+		return NULL;
+
+	dp->ds = ds;
+	dp->index = index;
+
+	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)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_switch_tree *dst = ds->dst;
+	const struct dsa_device_ops *tag_ops;
+	enum dsa_tag_protocol tag_protocol;
+
+	tag_protocol = dsa_get_tag_protocol(dp, master);
+	tag_ops = dsa_tag_driver_get(tag_protocol);
+	if (IS_ERR(tag_ops)) {
+		if (PTR_ERR(tag_ops) == -ENOPROTOOPT)
+			return -EPROBE_DEFER;
+		dev_warn(ds->dev, "No tagger for this switch\n");
+		dp->master = NULL;
+		return PTR_ERR(tag_ops);
+	}
+
+	dp->master = master;
+	dp->type = DSA_PORT_TYPE_CPU;
+	dp->filter = tag_ops->filter;
+	dp->rcv = tag_ops->rcv;
+	dp->tag_ops = tag_ops;
+	dp->dst = dst;
+
+	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;
+
+		master = of_find_net_device_by_node(ethernet);
+		of_node_put(ethernet);
+		if (!master)
+			return -EPROBE_DEFER;
+
+		return dsa_port_parse_cpu(dp, master);
+	}
+
+	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)
+			goto out_put_node;
+
+		if (reg >= ds->num_ports) {
+			err = -EINVAL;
+			goto out_put_node;
+		}
+
+		dp = dsa_to_port(ds, reg);
+
+		err = dsa_port_parse_of(dp, port);
+		if (err)
+			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;
+
+	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);
+	}
+
+	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_switch_tree *dst = ds->dst;
+	struct dsa_port *dp, *next;
+
+	list_for_each_entry_safe(dp, next, &dst->ports, list) {
+		if (dp->ds != ds)
+			continue;
+		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);
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
new file mode 100644
index 000000000..12998bf04
--- /dev/null
+++ b/net/dsa/dsa_priv.h
@@ -0,0 +1,264 @@
+/* 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/phy.h>
+#include <linux/netdevice.h>
+#include <linux/netpoll.h>
+#include <net/dsa.h>
+#include <net/gro_cells.h>
+
+enum {
+	DSA_NOTIFIER_AGEING_TIME,
+	DSA_NOTIFIER_BRIDGE_JOIN,
+	DSA_NOTIFIER_BRIDGE_LEAVE,
+	DSA_NOTIFIER_FDB_ADD,
+	DSA_NOTIFIER_FDB_DEL,
+	DSA_NOTIFIER_MDB_ADD,
+	DSA_NOTIFIER_MDB_DEL,
+	DSA_NOTIFIER_VLAN_ADD,
+	DSA_NOTIFIER_VLAN_DEL,
+	DSA_NOTIFIER_MTU,
+};
+
+/* DSA_NOTIFIER_AGEING_TIME */
+struct dsa_notifier_ageing_time_info {
+	struct switchdev_trans *trans;
+	unsigned int ageing_time;
+};
+
+/* DSA_NOTIFIER_BRIDGE_* */
+struct dsa_notifier_bridge_info {
+	struct net_device *br;
+	int tree_index;
+	int sw_index;
+	int port;
+};
+
+/* DSA_NOTIFIER_FDB_* */
+struct dsa_notifier_fdb_info {
+	int sw_index;
+	int port;
+	const unsigned char *addr;
+	u16 vid;
+};
+
+/* DSA_NOTIFIER_MDB_* */
+struct dsa_notifier_mdb_info {
+	const struct switchdev_obj_port_mdb *mdb;
+	struct switchdev_trans *trans;
+	int sw_index;
+	int port;
+};
+
+/* DSA_NOTIFIER_VLAN_* */
+struct dsa_notifier_vlan_info {
+	const struct switchdev_obj_port_vlan *vlan;
+	struct switchdev_trans *trans;
+	int sw_index;
+	int port;
+};
+
+/* DSA_NOTIFIER_MTU */
+struct dsa_notifier_mtu_info {
+	bool propagate_upstream;
+	int sw_index;
+	int port;
+	int mtu;
+};
+
+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 pcpu_sw_netstats	__percpu *stats64;
+
+	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);
+
+bool dsa_schedule_work(struct work_struct *work);
+const char *dsa_tag_protocol_to_str(const struct dsa_device_ops *ops);
+
+int dsa_legacy_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
+		       struct net_device *dev,
+		       const unsigned char *addr, u16 vid,
+		       u16 flags,
+		       struct netlink_ext_ack *extack);
+int dsa_legacy_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
+		       struct net_device *dev,
+		       const unsigned char *addr, u16 vid);
+
+/* master.c */
+int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp);
+void dsa_master_teardown(struct net_device *dev);
+
+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;
+}
+
+/* port.c */
+int dsa_port_set_state(struct dsa_port *dp, u8 state,
+		       struct switchdev_trans *trans);
+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);
+void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br);
+int dsa_port_vlan_filtering(struct dsa_port *dp, bool vlan_filtering,
+			    struct switchdev_trans *trans);
+bool dsa_port_skip_vlan_configuration(struct dsa_port *dp);
+int dsa_port_ageing_time(struct dsa_port *dp, clock_t ageing_clock,
+			 struct switchdev_trans *trans);
+int dsa_port_mtu_change(struct dsa_port *dp, int new_mtu,
+			bool propagate_upstream);
+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_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,
+		     struct switchdev_trans *trans);
+int dsa_port_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, unsigned long flags,
+			      struct switchdev_trans *trans);
+int dsa_port_bridge_flags(const struct dsa_port *dp, unsigned long flags,
+			  struct switchdev_trans *trans);
+int dsa_port_mrouter(struct dsa_port *dp, bool mrouter,
+		     struct switchdev_trans *trans);
+int dsa_port_vlan_add(struct dsa_port *dp,
+		      const struct switchdev_obj_port_vlan *vlan,
+		      struct switchdev_trans *trans);
+int dsa_port_vlan_del(struct dsa_port *dp,
+		      const struct switchdev_obj_port_vlan *vlan);
+int dsa_port_link_register_of(struct dsa_port *dp);
+void dsa_port_link_unregister_of(struct dsa_port *dp);
+extern const struct phylink_mac_ops dsa_port_phylink_mac_ops;
+
+/* slave.c */
+extern const struct dsa_device_ops notag_netdev_ops;
+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);
+bool dsa_slave_dev_check(const struct net_device *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);
+
+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 dp->cpu_dp->master;
+}
+
+/* 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 = dp->bridge_dev;
+	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;
+}
+
+/* switch.c */
+int dsa_switch_register_notifier(struct dsa_switch *ds);
+void dsa_switch_unregister_notifier(struct dsa_switch *ds);
+
+/* dsa2.c */
+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..45bd627b4
--- /dev/null
+++ b/net/dsa/master.c
@@ -0,0 +1,378 @@
+// 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;
+	strlcpy(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 (dp->ds->ops->port_hwtstamp_get ||
+			    dp->ds->ops->port_hwtstamp_set)
+				return -EBUSY;
+		break;
+	}
+
+	if (dev->netdev_ops->ndo_do_ioctl)
+		err = dev->netdev_ops->ndo_do_ioctl(dev, ifr, cmd);
+
+	return err;
+}
+
+static const struct dsa_netdevice_ops dsa_netdev_ops = {
+	.ndo_do_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;
+
+	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;
+
+	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)
+{
+	dev->dsa_ptr->netdev_ops = ops;
+}
+
+static void dsa_master_set_promiscuity(struct net_device *dev, int inc)
+{
+	const struct dsa_device_ops *ops = dev->dsa_ptr->tag_ops;
+
+	if (!ops->promisc_on_master)
+		return;
+
+	rtnl_lock();
+	dev_set_promiscuity(dev, inc);
+	rtnl_unlock();
+}
+
+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 DEVICE_ATTR_RO(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;
+
+	rtnl_lock();
+	err = dev_set_mtu(dev, ETH_DATA_LEN);
+	if (err)
+		netdev_dbg(dev,
+			   "Unable to reset MTU to exclude DSA overheads\n");
+	rtnl_unlock();
+}
+
+static struct lock_class_key dsa_master_addr_list_lock_key;
+
+int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
+{
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct device_link *consumer_link;
+	int ret;
+
+	/* The DSA master must use SET_NETDEV_DEV for this to work. */
+	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));
+
+	rtnl_lock();
+	ret = dev_set_mtu(dev, ETH_DATA_LEN + cpu_dp->tag_ops->overhead);
+	rtnl_unlock();
+	if (ret)
+		netdev_warn(dev, "error %d setting MTU to include DSA overhead\n",
+			    ret);
+
+	/* 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;
+	lockdep_set_class(&dev->addr_list_lock,
+			  &dsa_master_addr_list_lock_key);
+
+	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();
+}
diff --git a/net/dsa/port.c b/net/dsa/port.c
new file mode 100644
index 000000000..c9d552c4c
--- /dev/null
+++ b/net/dsa/port.c
@@ -0,0 +1,814 @@
+// 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/notifier.h>
+#include <linux/of_mdio.h>
+#include <linux/of_net.h>
+
+#include "dsa_priv.h"
+
+static 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) {
+		struct raw_notifier_head *nh = &dst->nh;
+
+		err = raw_notifier_call_chain(nh, e, v);
+		err = notifier_to_errno(err);
+		if (err)
+			break;
+	}
+
+	return err;
+}
+
+static int dsa_port_notify(const struct dsa_port *dp, unsigned long e, void *v)
+{
+	struct raw_notifier_head *nh = &dp->ds->dst->nh;
+	int err;
+
+	err = raw_notifier_call_chain(nh, e, v);
+
+	return notifier_to_errno(err);
+}
+
+int dsa_port_set_state(struct dsa_port *dp, u8 state,
+		       struct switchdev_trans *trans)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+
+	if (switchdev_trans_ph_prepare(trans))
+		return ds->ops->port_stp_state_set ? 0 : -EOPNOTSUPP;
+
+	if (ds->ops->port_stp_state_set)
+		ds->ops->port_stp_state_set(ds, port, state);
+
+	if (ds->ops->port_fast_age) {
+		/* 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.
+		 */
+
+		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))
+			ds->ops->port_fast_age(ds, port);
+	}
+
+	dp->stp_state = state;
+
+	return 0;
+}
+
+static void dsa_port_set_state_now(struct dsa_port *dp, u8 state)
+{
+	int err;
+
+	err = dsa_port_set_state(dp, state, NULL);
+	if (err)
+		pr_err("DSA: failed to set STP state %u (%d)\n", state, err);
+}
+
+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_dev)
+		dsa_port_set_state_now(dp, BR_STATE_FORWARDING);
+
+	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_dev)
+		dsa_port_set_state_now(dp, BR_STATE_DISABLED);
+
+	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();
+}
+
+int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br)
+{
+	struct dsa_notifier_bridge_info info = {
+		.tree_index = dp->ds->dst->index,
+		.sw_index = dp->ds->index,
+		.port = dp->index,
+		.br = br,
+	};
+	int err;
+
+	/* Set the flooding mode before joining the port in the switch */
+	err = dsa_port_bridge_flags(dp, BR_FLOOD | BR_MCAST_FLOOD, NULL);
+	if (err)
+		return err;
+
+	/* Here the interface is already bridged. Reflect the current
+	 * configuration so that drivers can program their chips accordingly.
+	 */
+	dp->bridge_dev = br;
+
+	err = dsa_broadcast(DSA_NOTIFIER_BRIDGE_JOIN, &info);
+
+	/* The bridging is rolled back on error */
+	if (err) {
+		dsa_port_bridge_flags(dp, 0, NULL);
+		dp->bridge_dev = NULL;
+	}
+
+	return err;
+}
+
+void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br)
+{
+	struct dsa_notifier_bridge_info info = {
+		.tree_index = dp->ds->dst->index,
+		.sw_index = dp->ds->index,
+		.port = dp->index,
+		.br = br,
+	};
+	int err;
+
+	/* Here the port is already unbridged. Reflect the current configuration
+	 * so that drivers can program their chips accordingly.
+	 */
+	dp->bridge_dev = NULL;
+
+	err = dsa_broadcast(DSA_NOTIFIER_BRIDGE_LEAVE, &info);
+	if (err)
+		pr_err("DSA: failed to notify DSA_NOTIFIER_BRIDGE_LEAVE\n");
+
+	/* Port is leaving the bridge, disable flooding */
+	dsa_port_bridge_flags(dp, 0, NULL);
+
+	/* 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);
+}
+
+/* Must be called under rcu_read_lock() */
+static bool dsa_port_can_apply_vlan_filtering(struct dsa_port *dp,
+					      bool vlan_filtering)
+{
+	struct dsa_switch *ds = dp->ds;
+	int err, i;
+
+	/* 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_is_user_port(ds, dp->index)) {
+		struct net_device *upper_dev, *slave = dp->slave;
+		struct net_device *br = dp->bridge_dev;
+		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) {
+				dev_err(ds->dev, "Must remove upper %s first\n",
+					upper_dev->name);
+				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.
+	 */
+	for (i = 0; i < ds->num_ports; i++) {
+		struct net_device *other_bridge;
+
+		other_bridge = dsa_to_port(ds, i)->bridge_dev;
+		if (!other_bridge)
+			continue;
+		/* If it's the same bridge, it also has same
+		 * vlan_filtering setting => no need to check
+		 */
+		if (other_bridge == dp->bridge_dev)
+			continue;
+		if (br_vlan_enabled(other_bridge) != vlan_filtering) {
+			dev_err(ds->dev, "VLAN filtering is a global setting\n");
+			return false;
+		}
+	}
+	return true;
+}
+
+int dsa_port_vlan_filtering(struct dsa_port *dp, bool vlan_filtering,
+			    struct switchdev_trans *trans)
+{
+	struct dsa_switch *ds = dp->ds;
+	int err;
+
+	if (switchdev_trans_ph_prepare(trans)) {
+		bool apply;
+
+		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);
+		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,
+					   trans);
+	if (err)
+		return err;
+
+	if (switchdev_trans_ph_commit(trans)) {
+		if (ds->vlan_filtering_is_global)
+			ds->vlan_filtering = vlan_filtering;
+		else
+			dp->vlan_filtering = vlan_filtering;
+	}
+
+	return 0;
+}
+
+/* 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 dsa_switch *ds = dp->ds;
+
+	if (!dp->bridge_dev)
+		return false;
+
+	return (!ds->configure_vlan_while_not_filtering &&
+		!br_vlan_enabled(dp->bridge_dev));
+}
+
+int dsa_port_ageing_time(struct dsa_port *dp, clock_t ageing_clock,
+			 struct switchdev_trans *trans)
+{
+	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 = {
+		.ageing_time = ageing_time,
+		.trans = trans,
+	};
+
+	if (switchdev_trans_ph_prepare(trans))
+		return dsa_port_notify(dp, DSA_NOTIFIER_AGEING_TIME, &info);
+
+	dp->ageing_time = ageing_time;
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_AGEING_TIME, &info);
+}
+
+int dsa_port_pre_bridge_flags(const struct dsa_port *dp, unsigned long flags,
+			      struct switchdev_trans *trans)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->port_egress_floods ||
+	    (flags & ~(BR_FLOOD | BR_MCAST_FLOOD)))
+		return -EINVAL;
+
+	return 0;
+}
+
+int dsa_port_bridge_flags(const struct dsa_port *dp, unsigned long flags,
+			  struct switchdev_trans *trans)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+	int err = 0;
+
+	if (switchdev_trans_ph_prepare(trans))
+		return 0;
+
+	if (ds->ops->port_egress_floods)
+		err = ds->ops->port_egress_floods(ds, port, flags & BR_FLOOD,
+						  flags & BR_MCAST_FLOOD);
+
+	return err;
+}
+
+int dsa_port_mrouter(struct dsa_port *dp, bool mrouter,
+		     struct switchdev_trans *trans)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+
+	if (switchdev_trans_ph_prepare(trans))
+		return ds->ops->port_egress_floods ? 0 : -EOPNOTSUPP;
+
+	return ds->ops->port_egress_floods(ds, port, true, mrouter);
+}
+
+int dsa_port_mtu_change(struct dsa_port *dp, int new_mtu,
+			bool propagate_upstream)
+{
+	struct dsa_notifier_mtu_info info = {
+		.sw_index = dp->ds->index,
+		.propagate_upstream = propagate_upstream,
+		.port = dp->index,
+		.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 = {
+		.sw_index = dp->ds->index,
+		.port = dp->index,
+		.addr = addr,
+		.vid = vid,
+	};
+
+	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 = {
+		.sw_index = dp->ds->index,
+		.port = dp->index,
+		.addr = addr,
+		.vid = vid,
+
+	};
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_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 switchdev_trans *trans)
+{
+	struct dsa_notifier_mdb_info info = {
+		.sw_index = dp->ds->index,
+		.port = dp->index,
+		.trans = trans,
+		.mdb = mdb,
+	};
+
+	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 = {
+		.sw_index = dp->ds->index,
+		.port = dp->index,
+		.mdb = mdb,
+	};
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_MDB_DEL, &info);
+}
+
+int dsa_port_vlan_add(struct dsa_port *dp,
+		      const struct switchdev_obj_port_vlan *vlan,
+		      struct switchdev_trans *trans)
+{
+	struct dsa_notifier_vlan_info info = {
+		.sw_index = dp->ds->index,
+		.port = dp->index,
+		.trans = trans,
+		.vlan = vlan,
+	};
+
+	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 = {
+		.sw_index = dp->ds->index,
+		.port = dp->index,
+		.vlan = vlan,
+	};
+
+	return dsa_port_notify(dp, DSA_NOTIFIER_VLAN_DEL, &info);
+}
+
+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)
+		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 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_is_user_port(ds, dp->index))
+		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);
+}
+
+const struct phylink_mac_ops dsa_port_phylink_mac_ops = {
+	.validate = dsa_port_phylink_validate,
+	.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,
+};
+
+static int dsa_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_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_port_phylink_register(struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct device_node *port_dn = dp->dn;
+	phy_interface_t mode;
+	int err;
+
+	err = of_get_phy_mode(port_dn, &mode);
+	if (err)
+		mode = PHY_INTERFACE_MODE_NA;
+
+	dp->pl_config.dev = ds->dev;
+	dp->pl_config.type = PHYLINK_DEV;
+	dp->pl_config.pcs_poll = ds->pcs_poll;
+
+	dp->pl = phylink_create(&dp->pl_config, of_fwnode_handle(port_dn),
+				mode, &dsa_port_phylink_mac_ops);
+	if (IS_ERR(dp->pl)) {
+		pr_err("error creating PHYLINK: %ld\n", PTR_ERR(dp->pl));
+		return PTR_ERR(dp->pl);
+	}
+
+	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:
+	phylink_destroy(dp->pl);
+	return err;
+}
+
+int dsa_port_link_register_of(struct dsa_port *dp)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct device_node *phy_np;
+	int port = dp->index;
+
+	if (!ds->ops->adjust_link) {
+		phy_np = of_parse_phandle(dp->dn, "phy-handle", 0);
+		if (of_phy_is_fixed_link(dp->dn) || phy_np) {
+			if (ds->ops->phylink_mac_link_down)
+				ds->ops->phylink_mac_link_down(ds, port,
+					MLO_AN_FIXED, PHY_INTERFACE_MODE_NA);
+			of_node_put(phy_np);
+			return dsa_port_phylink_register(dp);
+		}
+		of_node_put(phy_np);
+		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_port_fixed_link_register_of(dp);
+	else
+		return dsa_port_setup_phy_of(dp, true);
+}
+
+void dsa_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();
+		phylink_destroy(dp->pl);
+		dp->pl = NULL;
+		return;
+	}
+
+	if (of_phy_is_fixed_link(dp->dn))
+		of_phy_deregister_fixed_link(dp->dn);
+	else
+		dsa_port_setup_phy_of(dp, false);
+}
+
+int dsa_port_get_phy_strings(struct dsa_port *dp, uint8_t *data)
+{
+	struct phy_device *phydev;
+	int ret = -EOPNOTSUPP;
+
+	if (of_phy_is_fixed_link(dp->dn))
+		return ret;
+
+	phydev = dsa_port_get_phy_device(dp);
+	if (IS_ERR_OR_NULL(phydev))
+		return ret;
+
+	ret = phy_ethtool_get_strings(phydev, data);
+	put_device(&phydev->mdio.dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dsa_port_get_phy_strings);
+
+int dsa_port_get_ethtool_phy_stats(struct dsa_port *dp, uint64_t *data)
+{
+	struct phy_device *phydev;
+	int ret = -EOPNOTSUPP;
+
+	if (of_phy_is_fixed_link(dp->dn))
+		return ret;
+
+	phydev = dsa_port_get_phy_device(dp);
+	if (IS_ERR_OR_NULL(phydev))
+		return ret;
+
+	ret = phy_ethtool_get_stats(phydev, NULL, data);
+	put_device(&phydev->mdio.dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dsa_port_get_ethtool_phy_stats);
+
+int dsa_port_get_phy_sset_count(struct dsa_port *dp)
+{
+	struct phy_device *phydev;
+	int ret = -EOPNOTSUPP;
+
+	if (of_phy_is_fixed_link(dp->dn))
+		return ret;
+
+	phydev = dsa_port_get_phy_device(dp);
+	if (IS_ERR_OR_NULL(phydev))
+		return ret;
+
+	ret = phy_ethtool_get_sset_count(phydev);
+	put_device(&phydev->mdio.dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dsa_port_get_phy_sset_count);
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
new file mode 100644
index 000000000..65b125bb3
--- /dev/null
+++ b/net/dsa/slave.c
@@ -0,0 +1,2251 @@
+// 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/tc_act/tc_mirred.h>
+#include <linux/if_bridge.h>
+#include <linux/netpoll.h>
+#include <linux/ptp_classify.h>
+
+#include "dsa_priv.h"
+
+/* 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);
+	int err;
+
+	if (!(master->flags & IFF_UP))
+		return -ENETDOWN;
+
+	if (!ether_addr_equal(dev->dev_addr, master->dev_addr)) {
+		err = dev_uc_add(master, dev->dev_addr);
+		if (err < 0)
+			goto out;
+	}
+
+	if (dev->flags & IFF_ALLMULTI) {
+		err = dev_set_allmulti(master, 1);
+		if (err < 0)
+			goto del_unicast;
+	}
+	if (dev->flags & IFF_PROMISC) {
+		err = dev_set_promiscuity(master, 1);
+		if (err < 0)
+			goto clear_allmulti;
+	}
+
+	err = dsa_port_enable_rt(dp, dev->phydev);
+	if (err)
+		goto clear_promisc;
+
+	return 0;
+
+clear_promisc:
+	if (dev->flags & IFF_PROMISC)
+		dev_set_promiscuity(master, -1);
+clear_allmulti:
+	if (dev->flags & IFF_ALLMULTI)
+		dev_set_allmulti(master, -1);
+del_unicast:
+	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
+		dev_uc_del(master, dev->dev_addr);
+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);
+
+	dsa_port_disable_rt(dp);
+
+	dev_mc_unsync(master, dev);
+	dev_uc_unsync(master, dev);
+	if (dev->flags & IFF_ALLMULTI)
+		dev_set_allmulti(master, -1);
+	if (dev->flags & IFF_PROMISC)
+		dev_set_promiscuity(master, -1);
+
+	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
+		dev_uc_del(master, dev->dev_addr);
+
+	return 0;
+}
+
+static void dsa_slave_change_rx_flags(struct net_device *dev, int change)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	if (dev->flags & IFF_UP) {
+		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);
+	}
+}
+
+static void dsa_slave_set_rx_mode(struct net_device *dev)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+
+	dev_mc_sync(master, dev);
+	dev_uc_sync(master, dev);
+}
+
+static int dsa_slave_set_mac_address(struct net_device *dev, void *a)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct sockaddr *addr = a;
+	int err;
+
+	if (!is_valid_ether_addr(addr->sa_data))
+		return -EADDRNOTAVAIL;
+
+	if (!(dev->flags & IFF_UP))
+		goto out;
+
+	if (!ether_addr_equal(addr->sa_data, master->dev_addr)) {
+		err = dev_uc_add(master, addr->sa_data);
+		if (err < 0)
+			return err;
+	}
+
+	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
+		dev_uc_del(master, dev->dev_addr);
+
+out:
+	ether_addr_copy(dev->dev_addr, addr->sa_data);
+
+	return 0;
+}
+
+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 struct switchdev_attr *attr,
+				   struct switchdev_trans *trans)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	int ret;
+
+	switch (attr->id) {
+	case SWITCHDEV_ATTR_ID_PORT_STP_STATE:
+		ret = dsa_port_set_state(dp, attr->u.stp_state, trans);
+		break;
+	case SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING:
+		ret = dsa_port_vlan_filtering(dp, attr->u.vlan_filtering,
+					      trans);
+		break;
+	case SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME:
+		ret = dsa_port_ageing_time(dp, attr->u.ageing_time, trans);
+		break;
+	case SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS:
+		ret = dsa_port_pre_bridge_flags(dp, attr->u.brport_flags,
+						trans);
+		break;
+	case SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS:
+		ret = dsa_port_bridge_flags(dp, attr->u.brport_flags, trans);
+		break;
+	case SWITCHDEV_ATTR_ID_BRIDGE_MROUTER:
+		ret = dsa_port_mrouter(dp->cpu_dp, attr->u.mrouter, trans);
+		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_begin && vid <= vlan->vid_end)
+			return -EBUSY;
+	}
+
+	return 0;
+}
+
+static int dsa_slave_vlan_add(struct net_device *dev,
+			      const struct switchdev_obj *obj,
+			      struct switchdev_trans *trans)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_vlan vlan;
+	int vid, err;
+
+	if (obj->orig_dev != dev)
+		return -EOPNOTSUPP;
+
+	if (dsa_port_skip_vlan_configuration(dp))
+		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 (trans->ph_prepare && br_vlan_enabled(dp->bridge_dev)) {
+		rcu_read_lock();
+		err = dsa_slave_vlan_check_for_8021q_uppers(dev, &vlan);
+		rcu_read_unlock();
+		if (err)
+			return err;
+	}
+
+	err = dsa_port_vlan_add(dp, &vlan, trans);
+	if (err)
+		return err;
+
+	/* We need the dedicated CPU port to be a member of the VLAN as well.
+	 * 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;
+
+	err = dsa_port_vlan_add(dp->cpu_dp, &vlan, trans);
+	if (err)
+		return err;
+
+	for (vid = vlan.vid_begin; vid <= vlan.vid_end; vid++) {
+		err = vlan_vid_add(master, htons(ETH_P_8021Q), vid);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int dsa_slave_port_obj_add(struct net_device *dev,
+				  const struct switchdev_obj *obj,
+				  struct switchdev_trans *trans,
+				  struct netlink_ext_ack *extack)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	int err;
+
+	/* For the prepare phase, ensure the full set of changes is feasable in
+	 * one go in order to signal a failure properly. If an operation is not
+	 * supported, return -EOPNOTSUPP.
+	 */
+
+	switch (obj->id) {
+	case SWITCHDEV_OBJ_ID_PORT_MDB:
+		if (obj->orig_dev != dev)
+			return -EOPNOTSUPP;
+		err = dsa_port_mdb_add(dp, SWITCHDEV_OBJ_PORT_MDB(obj), trans);
+		break;
+	case SWITCHDEV_OBJ_ID_HOST_MDB:
+		/* DSA can directly translate this to a normal MDB add,
+		 * but on the CPU port.
+		 */
+		err = dsa_port_mdb_add(dp->cpu_dp, SWITCHDEV_OBJ_PORT_MDB(obj),
+				       trans);
+		break;
+	case SWITCHDEV_OBJ_ID_PORT_VLAN:
+		err = dsa_slave_vlan_add(dev, obj, trans);
+		break;
+	default:
+		err = -EOPNOTSUPP;
+		break;
+	}
+
+	return err;
+}
+
+static int dsa_slave_vlan_del(struct net_device *dev,
+			      const struct switchdev_obj *obj)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_vlan *vlan;
+	int vid, err;
+
+	if (obj->orig_dev != dev)
+		return -EOPNOTSUPP;
+
+	if (dsa_port_skip_vlan_configuration(dp))
+		return 0;
+
+	vlan = SWITCHDEV_OBJ_PORT_VLAN(obj);
+
+	/* Do not deprogram the CPU port as it may be shared with other user
+	 * ports which can be members of this VLAN as well.
+	 */
+	err = dsa_port_vlan_del(dp, vlan);
+	if (err)
+		return err;
+
+	for (vid = vlan->vid_begin; vid <= vlan->vid_end; vid++)
+		vlan_vid_del(master, htons(ETH_P_8021Q), vid);
+
+	return 0;
+}
+
+static int dsa_slave_port_obj_del(struct net_device *dev,
+				  const struct switchdev_obj *obj)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	int err;
+
+	switch (obj->id) {
+	case SWITCHDEV_OBJ_ID_PORT_MDB:
+		if (obj->orig_dev != dev)
+			return -EOPNOTSUPP;
+		err = dsa_port_mdb_del(dp, SWITCHDEV_OBJ_PORT_MDB(obj));
+		break;
+	case SWITCHDEV_OBJ_ID_HOST_MDB:
+		/* DSA can directly translate this to a normal MDB add,
+		 * but on the CPU port.
+		 */
+		err = dsa_port_mdb_del(dp->cpu_dp, SWITCHDEV_OBJ_PORT_MDB(obj));
+		break;
+	case SWITCHDEV_OBJ_ID_PORT_VLAN:
+		err = dsa_slave_vlan_del(dev, obj);
+		break;
+	default:
+		err = -EOPNOTSUPP;
+		break;
+	}
+
+	return err;
+}
+
+static int dsa_slave_get_port_parent_id(struct net_device *dev,
+					struct netdev_phys_item_id *ppid)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_switch_tree *dst = ds->dst;
+
+	/* For non-legacy ports, devlink is used and it takes
+	 * care of the name generation. This ndo implementation
+	 * should be removed with legacy support.
+	 */
+	if (dp->ds->devlink)
+		return -EOPNOTSUPP;
+
+	ppid->id_len = sizeof(dst->index);
+	memcpy(&ppid->id, &dst->index, ppid->id_len);
+
+	return 0;
+}
+
+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;
+	struct sk_buff *clone;
+	unsigned int type;
+
+	type = ptp_classify_raw(skb);
+	if (type == PTP_CLASS_NONE)
+		return;
+
+	if (!ds->ops->port_txtstamp)
+		return;
+
+	clone = skb_clone_sk(skb);
+	if (!clone)
+		return;
+
+	DSA_SKB_CB(skb)->clone = clone;
+
+	if (ds->ops->port_txtstamp(ds, p->dp->index, clone, type))
+		return;
+
+	kfree_skb(clone);
+}
+
+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 pcpu_sw_netstats *s;
+	struct sk_buff *nskb;
+
+	s = this_cpu_ptr(p->stats64);
+	u64_stats_update_begin(&s->syncp);
+	s->tx_packets++;
+	s->tx_bytes += skb->len;
+	u64_stats_update_end(&s->syncp);
+
+	DSA_SKB_CB(skb)->clone = NULL;
+
+	/* Identify PTP protocol packets, clone them, and pass them to the
+	 * switch driver
+	 */
+	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)
+{
+	strlcpy(drvinfo->driver, "dsa", sizeof(drvinfo->driver));
+	strlcpy(drvinfo->fw_version, "N/A", sizeof(drvinfo->fw_version));
+	strlcpy(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);
+	}
+}
+
+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_slave_priv *p = netdev_priv(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(p->stats64, i);
+		do {
+			start = u64_stats_fetch_begin_irq(&s->syncp);
+			tx_packets = s->tx_packets;
+			tx_bytes = s->tx_bytes;
+			rx_packets = s->rx_packets;
+			rx_bytes = 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;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+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_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 int dsa_slave_get_phys_port_name(struct net_device *dev,
+					char *name, size_t len)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	/* For non-legacy ports, devlink is used and it takes
+	 * care of the name generation. This ndo implementation
+	 * should be removed with legacy support.
+	 */
+	if (dp->ds->devlink)
+		return -EOPNOTSUPP;
+
+	if (snprintf(name, len, "p%d", dp->index) >= len)
+		return -EINVAL;
+
+	return 0;
+}
+
+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 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);
+	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_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;
+
+	if (type == TC_SETUP_BLOCK)
+		return dsa_slave_setup_tc_block(dev, type_data);
+
+	if (!ds->ops->port_setup_tc)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_setup_tc(ds, dp->index, type, type_data);
+}
+
+static void dsa_slave_get_stats64(struct net_device *dev,
+				  struct rtnl_link_stats64 *stats)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+
+	netdev_stats_to_stats64(stats, &dev->stats);
+	dev_fetch_sw_netstats(stats, p->stats64);
+}
+
+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 net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_vlan vlan = {
+		.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
+		.vid_begin = vid,
+		.vid_end = vid,
+		/* This API only allows programming tagged, non-PVID VIDs */
+		.flags = 0,
+	};
+	struct switchdev_trans trans;
+	int ret;
+
+	/* User port... */
+	trans.ph_prepare = true;
+	ret = dsa_port_vlan_add(dp, &vlan, &trans);
+	if (ret)
+		return ret;
+
+	trans.ph_prepare = false;
+	ret = dsa_port_vlan_add(dp, &vlan, &trans);
+	if (ret)
+		return ret;
+
+	/* And CPU port... */
+	trans.ph_prepare = true;
+	ret = dsa_port_vlan_add(dp->cpu_dp, &vlan, &trans);
+	if (ret)
+		return ret;
+
+	trans.ph_prepare = false;
+	ret = dsa_port_vlan_add(dp->cpu_dp, &vlan, &trans);
+	if (ret)
+		return ret;
+
+	return vlan_vid_add(master, proto, vid);
+}
+
+static int dsa_slave_vlan_rx_kill_vid(struct net_device *dev, __be16 proto,
+				      u16 vid)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct switchdev_obj_port_vlan vlan = {
+		.vid_begin = vid,
+		.vid_end = vid,
+		/* This API only allows programming tagged, non-PVID VIDs */
+		.flags = 0,
+	};
+	int err;
+
+	/* Do not deprogram the CPU port as it may be shared with other user
+	 * ports which can be members of this VLAN as well.
+	 */
+	err = dsa_port_vlan_del(dp, &vlan);
+	if (err)
+		return err;
+
+	vlan_vid_del(master, proto, vid);
+
+	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_dev)
+		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 (other_dp->bridge_dev != dp->bridge_dev)
+				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);
+}
+
+static 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_slave_priv *p = netdev_priv(dev);
+	struct dsa_switch *ds = p->dp->ds;
+	struct dsa_port *cpu_dp;
+	int port = p->dp->index;
+	int largest_mtu = 0;
+	int new_master_mtu;
+	int old_master_mtu;
+	int mtu_limit;
+	int cpu_mtu;
+	int err, i;
+
+	if (!ds->ops->port_change_mtu)
+		return -EOPNOTSUPP;
+
+	for (i = 0; i < ds->num_ports; i++) {
+		int slave_mtu;
+
+		if (!dsa_is_user_port(ds, i))
+			continue;
+
+		/* 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 (!dsa_to_port(ds, i)->slave)
+			continue;
+
+		/* Pretend that we already applied the setting, which we
+		 * actually haven't (still haven't done all integrity checks)
+		 */
+		if (i == port)
+			slave_mtu = new_mtu;
+		else
+			slave_mtu = dsa_to_port(ds, i)->slave->mtu;
+
+		if (largest_mtu < slave_mtu)
+			largest_mtu = slave_mtu;
+	}
+
+	cpu_dp = dsa_to_port(ds, port)->cpu_dp;
+
+	mtu_limit = min_t(int, master->max_mtu, dev->max_mtu);
+	old_master_mtu = master->mtu;
+	new_master_mtu = largest_mtu + cpu_dp->tag_ops->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.
+		 */
+		err = dsa_port_mtu_change(cpu_dp, cpu_mtu, true);
+		if (err)
+			goto out_cpu_failed;
+	}
+
+	err = dsa_port_mtu_change(dp, new_mtu, false);
+	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 -
+				    cpu_dp->tag_ops->overhead,
+				    true);
+out_cpu_failed:
+	if (new_master_mtu != old_master_mtu)
+		dev_set_mtu(master, old_master_mtu);
+out_master_failed:
+	return err;
+}
+
+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,
+	.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_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,
+};
+
+/* legacy way, bypassing the bridge *****************************************/
+int dsa_legacy_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
+		       struct net_device *dev,
+		       const unsigned char *addr, u16 vid,
+		       u16 flags,
+		       struct netlink_ext_ack *extack)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return dsa_port_fdb_add(dp, addr, vid);
+}
+
+int dsa_legacy_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
+		       struct net_device *dev,
+		       const unsigned char *addr, u16 vid)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return dsa_port_fdb_del(dp, addr, vid);
+}
+
+static struct devlink_port *dsa_slave_get_devlink_port(struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return dp->ds->devlink ? &dp->devlink_port : NULL;
+}
+
+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_add		= dsa_legacy_fdb_add,
+	.ndo_fdb_del		= dsa_legacy_fdb_del,
+	.ndo_fdb_dump		= dsa_slave_fdb_dump,
+	.ndo_do_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_get_phys_port_name	= dsa_slave_get_phys_port_name,
+	.ndo_setup_tc		= dsa_slave_setup_tc,
+	.ndo_get_stats64	= dsa_slave_get_stats64,
+	.ndo_get_port_parent_id	= dsa_slave_get_port_parent_id,
+	.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,
+};
+
+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)
+{
+	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;
+	}
+
+	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;
+	phy_interface_t mode;
+	u32 phy_flags = 0;
+	int ret;
+
+	ret = of_get_phy_mode(port_dn, &mode);
+	if (ret)
+		mode = PHY_INTERFACE_MODE_NA;
+
+	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;
+	}
+
+	dp->pl = phylink_create(&dp->pl_config, of_fwnode_handle(port_dn), mode,
+				&dsa_port_phylink_mac_ops);
+	if (IS_ERR(dp->pl)) {
+		netdev_err(slave_dev,
+			   "error creating PHYLINK: %ld\n", PTR_ERR(dp->pl));
+		return PTR_ERR(dp->pl);
+	}
+
+	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);
+	}
+	if (ret) {
+		netdev_err(slave_dev, "failed to connect to PHY: %pe\n",
+			   ERR_PTR(ret));
+		phylink_destroy(dp->pl);
+	}
+
+	return ret;
+}
+
+static struct lock_class_key dsa_slave_netdev_xmit_lock_key;
+static void dsa_slave_set_lockdep_class_one(struct net_device *dev,
+					    struct netdev_queue *txq,
+					    void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock,
+			  &dsa_slave_netdev_xmit_lock_key);
+}
+
+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;
+}
+
+static void dsa_slave_notify(struct net_device *dev, unsigned long val)
+{
+	struct net_device *master = dsa_slave_to_master(dev);
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_notifier_register_info rinfo = {
+		.switch_number = dp->ds->index,
+		.port_number = dp->index,
+		.master = master,
+		.info.dev = dev,
+	};
+
+	call_dsa_notifiers(val, dev, &rinfo.info);
+}
+
+int dsa_slave_create(struct dsa_port *port)
+{
+	const struct dsa_port *cpu_dp = port->cpu_dp;
+	struct net_device *master = cpu_dp->master;
+	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->features = master->vlan_features | NETIF_F_HW_TC;
+	if (ds->ops->port_vlan_add && ds->ops->port_vlan_del)
+		slave_dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
+	slave_dev->hw_features |= NETIF_F_HW_TC;
+	slave_dev->features |= NETIF_F_LLTX;
+	slave_dev->ethtool_ops = &dsa_slave_ethtool_ops;
+	if (!IS_ERR_OR_NULL(port->mac))
+		ether_addr_copy(slave_dev->dev_addr, port->mac);
+	else
+		eth_hw_addr_inherit(slave_dev, master);
+	slave_dev->priv_flags |= IFF_NO_QUEUE;
+	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);
+	if (cpu_dp->tag_ops->tail_tag)
+		slave_dev->needed_tailroom = cpu_dp->tag_ops->overhead;
+	else
+		slave_dev->needed_headroom = cpu_dp->tag_ops->overhead;
+	/* 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_dev->needed_headroom += master->needed_headroom;
+	slave_dev->needed_tailroom += master->needed_tailroom;
+	SET_NETDEV_DEVTYPE(slave_dev, &dsa_type);
+
+	netdev_for_each_tx_queue(slave_dev, dsa_slave_set_lockdep_class_one,
+				 NULL);
+
+	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);
+	p->stats64 = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
+	if (!p->stats64) {
+		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);
+	p->xmit = cpu_dp->tag_ops->xmit;
+	port->slave = slave_dev;
+
+	rtnl_lock();
+	ret = dsa_slave_change_mtu(slave_dev, ETH_DATA_LEN);
+	rtnl_unlock();
+	if (ret && ret != -EOPNOTSUPP)
+		dev_warn(ds->dev, "nonfatal error %d setting MTU on port %d\n",
+			 ret, port->index);
+
+	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;
+	}
+
+	dsa_slave_notify(slave_dev, DSA_PORT_REGISTER);
+
+	rtnl_lock();
+
+	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;
+	}
+
+	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();
+	phylink_destroy(p->dp->pl);
+out_gcells:
+	gro_cells_destroy(&p->gcells);
+out_free:
+	free_percpu(p->stats64);
+	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_slave_notify(slave_dev, DSA_PORT_UNREGISTER);
+	phylink_destroy(dp->pl);
+	gro_cells_destroy(&p->gcells);
+	free_percpu(p->stats64);
+	free_netdev(slave_dev);
+}
+
+bool dsa_slave_dev_check(const struct net_device *dev)
+{
+	return dev->netdev_ops == &dsa_slave_netdev_ops;
+}
+
+static int dsa_slave_changeupper(struct net_device *dev,
+				 struct netdev_notifier_changeupper_info *info)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	int err = NOTIFY_DONE;
+
+	if (netif_is_bridge_master(info->upper_dev)) {
+		if (info->linking) {
+			err = dsa_port_bridge_join(dp, info->upper_dev);
+			if (!err)
+				dsa_bridge_mtu_normalization(dp);
+			err = notifier_from_errno(err);
+		} else {
+			dsa_port_bridge_leave(dp, info->upper_dev);
+			err = NOTIFY_OK;
+		}
+	}
+
+	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;
+	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);
+	if (!dp->bridge_dev)
+		return NOTIFY_DONE;
+
+	/* Deny enslaving a VLAN device into a VLAN-aware bridge */
+	if (br_vlan_enabled(dp->bridge_dev) &&
+	    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 = dp->bridge_dev;
+	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_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;
+
+		if (!dsa_slave_dev_check(dev))
+			return dsa_prevent_bridging_8021q_upper(dev, ptr);
+
+		if (is_vlan_dev(info->upper_dev))
+			return dsa_slave_check_8021q_upper(dev, ptr);
+		break;
+	}
+	case NETDEV_CHANGEUPPER:
+		if (!dsa_slave_dev_check(dev))
+			return NOTIFY_DONE;
+
+		return dsa_slave_changeupper(dev, ptr);
+	}
+
+	return NOTIFY_DONE;
+}
+
+struct dsa_switchdev_event_work {
+	struct work_struct work;
+	struct switchdev_notifier_fdb_info fdb_info;
+	struct net_device *dev;
+	unsigned long event;
+};
+
+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);
+	struct net_device *dev = switchdev_work->dev;
+	struct switchdev_notifier_fdb_info *fdb_info;
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	int err;
+
+	rtnl_lock();
+	switch (switchdev_work->event) {
+	case SWITCHDEV_FDB_ADD_TO_DEVICE:
+		fdb_info = &switchdev_work->fdb_info;
+		if (!fdb_info->added_by_user)
+			break;
+
+		err = dsa_port_fdb_add(dp, fdb_info->addr, fdb_info->vid);
+		if (err) {
+			netdev_dbg(dev, "fdb add failed err=%d\n", err);
+			break;
+		}
+		fdb_info->offloaded = true;
+		call_switchdev_notifiers(SWITCHDEV_FDB_OFFLOADED, dev,
+					 &fdb_info->info, NULL);
+		break;
+
+	case SWITCHDEV_FDB_DEL_TO_DEVICE:
+		fdb_info = &switchdev_work->fdb_info;
+		if (!fdb_info->added_by_user)
+			break;
+
+		err = dsa_port_fdb_del(dp, fdb_info->addr, fdb_info->vid);
+		if (err) {
+			netdev_dbg(dev, "fdb del failed err=%d\n", err);
+			dev_close(dev);
+		}
+		break;
+	}
+	rtnl_unlock();
+
+	kfree(switchdev_work->fdb_info.addr);
+	kfree(switchdev_work);
+	dev_put(dev);
+}
+
+static int
+dsa_slave_switchdev_fdb_work_init(struct dsa_switchdev_event_work *
+				  switchdev_work,
+				  const struct switchdev_notifier_fdb_info *
+				  fdb_info)
+{
+	memcpy(&switchdev_work->fdb_info, fdb_info,
+	       sizeof(switchdev_work->fdb_info));
+	switchdev_work->fdb_info.addr = kzalloc(ETH_ALEN, GFP_ATOMIC);
+	if (!switchdev_work->fdb_info.addr)
+		return -ENOMEM;
+	ether_addr_copy((u8 *)switchdev_work->fdb_info.addr,
+			fdb_info->addr);
+	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);
+	struct dsa_switchdev_event_work *switchdev_work;
+	int err;
+
+	if (event == 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);
+	}
+
+	if (!dsa_slave_dev_check(dev))
+		return NOTIFY_DONE;
+
+	switchdev_work = kzalloc(sizeof(*switchdev_work), GFP_ATOMIC);
+	if (!switchdev_work)
+		return NOTIFY_BAD;
+
+	INIT_WORK(&switchdev_work->work,
+		  dsa_slave_switchdev_event_work);
+	switchdev_work->dev = dev;
+	switchdev_work->event = event;
+
+	switch (event) {
+	case SWITCHDEV_FDB_ADD_TO_DEVICE:
+	case SWITCHDEV_FDB_DEL_TO_DEVICE:
+		if (dsa_slave_switchdev_fdb_work_init(switchdev_work, ptr))
+			goto err_fdb_work_init;
+		dev_hold(dev);
+		break;
+	default:
+		kfree(switchdev_work);
+		return NOTIFY_DONE;
+	}
+
+	dsa_schedule_work(&switchdev_work->work);
+	return NOTIFY_OK;
+
+err_fdb_work_init:
+	kfree(switchdev_work);
+	return NOTIFY_BAD;
+}
+
+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(dev, ptr,
+						    dsa_slave_dev_check,
+						    dsa_slave_port_obj_add);
+		return notifier_from_errno(err);
+	case SWITCHDEV_PORT_OBJ_DEL:
+		err = switchdev_handle_port_obj_del(dev, ptr,
+						    dsa_slave_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,
+};
+
+static struct notifier_block dsa_slave_switchdev_notifier = {
+	.notifier_call = dsa_slave_switchdev_event,
+};
+
+static 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..a44035872
--- /dev/null
+++ b/net/dsa/switch.c
@@ -0,0 +1,373 @@
+// 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)
+{
+	int i;
+
+	for (i = 0; i < ds->num_ports; ++i) {
+		struct dsa_port *dp = dsa_to_port(ds, i);
+
+		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;
+	struct switchdev_trans *trans = info->trans;
+
+	if (switchdev_trans_ph_prepare(trans)) {
+		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;
+		return 0;
+	}
+
+	/* 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_switch_mtu_match(struct dsa_switch *ds, int port,
+				 struct dsa_notifier_mtu_info *info)
+{
+	if (ds->index == info->sw_index)
+		return (port == info->port) || dsa_is_dsa_port(ds, port);
+
+	if (!info->propagate_upstream)
+		return false;
+
+	if (dsa_is_dsa_port(ds, port) || dsa_is_cpu_port(ds, port))
+		return true;
+
+	return false;
+}
+
+static int dsa_switch_mtu(struct dsa_switch *ds,
+			  struct dsa_notifier_mtu_info *info)
+{
+	int port, ret;
+
+	if (!ds->ops->port_change_mtu)
+		return -EOPNOTSUPP;
+
+	for (port = 0; port < ds->num_ports; port++) {
+		if (dsa_switch_mtu_match(ds, port, info)) {
+			ret = ds->ops->port_change_mtu(ds, port, info->mtu);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_bridge_join(struct dsa_switch *ds,
+				  struct dsa_notifier_bridge_info *info)
+{
+	struct dsa_switch_tree *dst = ds->dst;
+
+	if (dst->index == info->tree_index && ds->index == info->sw_index &&
+	    ds->ops->port_bridge_join)
+		return ds->ops->port_bridge_join(ds, info->port, info->br);
+
+	if ((dst->index != info->tree_index || ds->index != info->sw_index) &&
+	    ds->ops->crosschip_bridge_join)
+		return ds->ops->crosschip_bridge_join(ds, info->tree_index,
+						      info->sw_index,
+						      info->port, info->br);
+
+	return 0;
+}
+
+static int dsa_switch_bridge_leave(struct dsa_switch *ds,
+				   struct dsa_notifier_bridge_info *info)
+{
+	bool unset_vlan_filtering = br_vlan_enabled(info->br);
+	struct dsa_switch_tree *dst = ds->dst;
+	int err, i;
+
+	if (dst->index == info->tree_index && ds->index == info->sw_index &&
+	    ds->ops->port_bridge_leave)
+		ds->ops->port_bridge_leave(ds, info->port, info->br);
+
+	if ((dst->index != info->tree_index || ds->index != info->sw_index) &&
+	    ds->ops->crosschip_bridge_leave)
+		ds->ops->crosschip_bridge_leave(ds, info->tree_index,
+						info->sw_index, info->port,
+						info->br);
+
+	/* 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 left this bridge.
+	 */
+	if (unset_vlan_filtering && ds->vlan_filtering_is_global) {
+		for (i = 0; i < ds->num_ports; i++) {
+			if (i == info->port)
+				continue;
+			if (dsa_to_port(ds, i)->bridge_dev == info->br) {
+				unset_vlan_filtering = false;
+				break;
+			}
+		}
+	}
+	if (unset_vlan_filtering) {
+		struct switchdev_trans trans;
+
+		trans.ph_prepare = true;
+		err = dsa_port_vlan_filtering(dsa_to_port(ds, info->port),
+					      false, &trans);
+		if (err && err != EOPNOTSUPP)
+			return err;
+
+		trans.ph_prepare = false;
+		err = dsa_port_vlan_filtering(dsa_to_port(ds, info->port),
+					      false, &trans);
+		if (err && err != EOPNOTSUPP)
+			return err;
+	}
+	return 0;
+}
+
+static int dsa_switch_fdb_add(struct dsa_switch *ds,
+			      struct dsa_notifier_fdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->sw_index, info->port);
+
+	if (!ds->ops->port_fdb_add)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_fdb_add(ds, port, info->addr, info->vid);
+}
+
+static int dsa_switch_fdb_del(struct dsa_switch *ds,
+			      struct dsa_notifier_fdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->sw_index, info->port);
+
+	if (!ds->ops->port_fdb_del)
+		return -EOPNOTSUPP;
+
+	return ds->ops->port_fdb_del(ds, port, info->addr, info->vid);
+}
+
+static bool dsa_switch_mdb_match(struct dsa_switch *ds, int port,
+				 struct dsa_notifier_mdb_info *info)
+{
+	if (ds->index == info->sw_index && port == info->port)
+		return true;
+
+	if (dsa_is_dsa_port(ds, port))
+		return true;
+
+	return false;
+}
+
+static int dsa_switch_mdb_prepare(struct dsa_switch *ds,
+				  struct dsa_notifier_mdb_info *info)
+{
+	int port, err;
+
+	if (!ds->ops->port_mdb_prepare || !ds->ops->port_mdb_add)
+		return -EOPNOTSUPP;
+
+	for (port = 0; port < ds->num_ports; port++) {
+		if (dsa_switch_mdb_match(ds, port, info)) {
+			err = ds->ops->port_mdb_prepare(ds, port, info->mdb);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_mdb_add(struct dsa_switch *ds,
+			      struct dsa_notifier_mdb_info *info)
+{
+	int port;
+
+	if (switchdev_trans_ph_prepare(info->trans))
+		return dsa_switch_mdb_prepare(ds, info);
+
+	if (!ds->ops->port_mdb_add)
+		return 0;
+
+	for (port = 0; port < ds->num_ports; port++)
+		if (dsa_switch_mdb_match(ds, port, info))
+			ds->ops->port_mdb_add(ds, port, info->mdb);
+
+	return 0;
+}
+
+static int dsa_switch_mdb_del(struct dsa_switch *ds,
+			      struct dsa_notifier_mdb_info *info)
+{
+	if (!ds->ops->port_mdb_del)
+		return -EOPNOTSUPP;
+
+	if (ds->index == info->sw_index)
+		return ds->ops->port_mdb_del(ds, info->port, info->mdb);
+
+	return 0;
+}
+
+static bool dsa_switch_vlan_match(struct dsa_switch *ds, int port,
+				  struct dsa_notifier_vlan_info *info)
+{
+	if (ds->index == info->sw_index && port == info->port)
+		return true;
+
+	if (dsa_is_dsa_port(ds, port))
+		return true;
+
+	return false;
+}
+
+static int dsa_switch_vlan_prepare(struct dsa_switch *ds,
+				   struct dsa_notifier_vlan_info *info)
+{
+	int port, err;
+
+	if (!ds->ops->port_vlan_prepare || !ds->ops->port_vlan_add)
+		return -EOPNOTSUPP;
+
+	for (port = 0; port < ds->num_ports; port++) {
+		if (dsa_switch_vlan_match(ds, port, info)) {
+			err = ds->ops->port_vlan_prepare(ds, port, info->vlan);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_vlan_add(struct dsa_switch *ds,
+			       struct dsa_notifier_vlan_info *info)
+{
+	int port;
+
+	if (switchdev_trans_ph_prepare(info->trans))
+		return dsa_switch_vlan_prepare(ds, info);
+
+	if (!ds->ops->port_vlan_add)
+		return 0;
+
+	for (port = 0; port < ds->num_ports; port++)
+		if (dsa_switch_vlan_match(ds, port, info))
+			ds->ops->port_vlan_add(ds, port, info->vlan);
+
+	return 0;
+}
+
+static int dsa_switch_vlan_del(struct dsa_switch *ds,
+			       struct dsa_notifier_vlan_info *info)
+{
+	if (!ds->ops->port_vlan_del)
+		return -EOPNOTSUPP;
+
+	if (ds->index == info->sw_index)
+		return ds->ops->port_vlan_del(ds, info->port, info->vlan);
+
+	/* Do not deprogram the DSA links as they may be used as conduit
+	 * for other VLAN members in the fabric.
+	 */
+	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_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_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_MTU:
+		err = dsa_switch_mtu(ds, info);
+		break;
+	default:
+		err = -EOPNOTSUPP;
+		break;
+	}
+
+	/* Non-switchdev operations cannot be rolled back. If a DSA driver
+	 * returns an error during the chained call, switch chips may be in an
+	 * inconsistent state.
+	 */
+	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..a00b513c2
--- /dev/null
+++ b/net/dsa/tag_8021q.c
@@ -0,0 +1,463 @@
+// 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. The
+ * dsa_8021q_netdev_ops is registered for API compliance and not used
+ * directly by callers.
+ */
+#include <linux/if_bridge.h>
+#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  |
+ * +-----------+-----+-----------------+-----------+-----------------------+
+ * |    DIR    | SVL |    SWITCH_ID    |  SUBVLAN  |          PORT         |
+ * +-----------+-----+-----------------+-----------+-----------------------+
+ *
+ * DIR - VID[11:10]:
+ *	Direction flags.
+ *	* 1 (0b01) for RX VLAN,
+ *	* 2 (0b10) for TX VLAN.
+ *	These values make the special VIDs of 0, 1 and 4095 to be left
+ *	unused by this coding scheme.
+ *
+ * SVL/SUBVLAN - { VID[9], VID[5:4] }:
+ *	Sub-VLAN encoding. Valid only when DIR indicates an RX VLAN.
+ *	* 0 (0b000): Field does not encode a sub-VLAN, either because
+ *	received traffic is untagged, PVID-tagged or because a second
+ *	VLAN tag is present after this tag and not inside of it.
+ *	* 1 (0b001): Received traffic is tagged with a VID value private
+ *	to the host. This field encodes the index in the host's lookup
+ *	table through which the value of the ingress VLAN ID can be
+ *	recovered.
+ *	* 2 (0b010): Field encodes a sub-VLAN.
+ *	...
+ *	* 7 (0b111): Field encodes a sub-VLAN.
+ *	When DIR indicates a TX VLAN, SUBVLAN must be transmitted as zero
+ *	(by the host) and ignored on receive (by the switch).
+ *
+ * SWITCH_ID - VID[8:6]:
+ *	Index of switch within DSA tree. Must be between 0 and 7.
+ *
+ * PORT - VID[3:0]:
+ *	Index of switch port. Must be between 0 and 15.
+ */
+
+#define DSA_8021Q_DIR_SHIFT		10
+#define DSA_8021Q_DIR_MASK		GENMASK(11, 10)
+#define DSA_8021Q_DIR(x)		(((x) << DSA_8021Q_DIR_SHIFT) & \
+						 DSA_8021Q_DIR_MASK)
+#define DSA_8021Q_DIR_RX		DSA_8021Q_DIR(1)
+#define DSA_8021Q_DIR_TX		DSA_8021Q_DIR(2)
+
+#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_SUBVLAN_HI_SHIFT	9
+#define DSA_8021Q_SUBVLAN_HI_MASK	GENMASK(9, 9)
+#define DSA_8021Q_SUBVLAN_LO_SHIFT	4
+#define DSA_8021Q_SUBVLAN_LO_MASK	GENMASK(5, 4)
+#define DSA_8021Q_SUBVLAN_HI(x)		(((x) & GENMASK(2, 2)) >> 2)
+#define DSA_8021Q_SUBVLAN_LO(x)		((x) & GENMASK(1, 0))
+#define DSA_8021Q_SUBVLAN(x)		\
+		(((DSA_8021Q_SUBVLAN_LO(x) << DSA_8021Q_SUBVLAN_LO_SHIFT) & \
+		  DSA_8021Q_SUBVLAN_LO_MASK) | \
+		 ((DSA_8021Q_SUBVLAN_HI(x) << DSA_8021Q_SUBVLAN_HI_SHIFT) & \
+		  DSA_8021Q_SUBVLAN_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)
+
+/* Returns the VID to be inserted into the frame from xmit for switch steering
+ * instructions on egress. Encodes switch ID and port ID.
+ */
+u16 dsa_8021q_tx_vid(struct dsa_switch *ds, int port)
+{
+	return DSA_8021Q_DIR_TX | DSA_8021Q_SWITCH_ID(ds->index) |
+	       DSA_8021Q_PORT(port);
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_tx_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_8021q_rx_vid(struct dsa_switch *ds, int port)
+{
+	return DSA_8021Q_DIR_RX | DSA_8021Q_SWITCH_ID(ds->index) |
+	       DSA_8021Q_PORT(port);
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_rx_vid);
+
+u16 dsa_8021q_rx_vid_subvlan(struct dsa_switch *ds, int port, u16 subvlan)
+{
+	return DSA_8021Q_DIR_RX | DSA_8021Q_SWITCH_ID(ds->index) |
+	       DSA_8021Q_PORT(port) | DSA_8021Q_SUBVLAN(subvlan);
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_rx_vid_subvlan);
+
+/* 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 subvlan from the RX VID. */
+u16 dsa_8021q_rx_subvlan(u16 vid)
+{
+	u16 svl_hi, svl_lo;
+
+	svl_hi = (vid & DSA_8021Q_SUBVLAN_HI_MASK) >>
+		 DSA_8021Q_SUBVLAN_HI_SHIFT;
+	svl_lo = (vid & DSA_8021Q_SUBVLAN_LO_MASK) >>
+		 DSA_8021Q_SUBVLAN_LO_SHIFT;
+
+	return (svl_hi << 2) | svl_lo;
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_rx_subvlan);
+
+bool vid_is_dsa_8021q(u16 vid)
+{
+	return ((vid & DSA_8021Q_DIR_MASK) == DSA_8021Q_DIR_RX ||
+		(vid & DSA_8021Q_DIR_MASK) == DSA_8021Q_DIR_TX);
+}
+EXPORT_SYMBOL_GPL(vid_is_dsa_8021q);
+
+/* If @enabled is true, installs @vid with @flags into the switch port's HW
+ * filter.
+ * If @enabled is false, deletes @vid (ignores @flags) from the port. Had the
+ * user explicitly configured this @vid through the bridge core, then the @vid
+ * is installed again, but this time with the flags from the bridge layer.
+ */
+static int dsa_8021q_vid_apply(struct dsa_8021q_context *ctx, int port, u16 vid,
+			       u16 flags, bool enabled)
+{
+	struct dsa_port *dp = dsa_to_port(ctx->ds, port);
+
+	if (enabled)
+		return ctx->ops->vlan_add(ctx->ds, dp->index, vid, flags);
+
+	return ctx->ops->vlan_del(ctx->ds, dp->index, vid);
+}
+
+/* RX VLAN tagging (left) and TX VLAN tagging (right) setup shown for a single
+ * front-panel switch port (here swp0).
+ *
+ * Port identification through VLAN (802.1Q) tags has different requirements
+ * for it to work effectively:
+ *  - On RX (ingress from network): each front-panel port must have a pvid
+ *    that uniquely identifies it, and the egress of this pvid must be tagged
+ *    towards the CPU port, so that software can recover the source port based
+ *    on the VID in the frame. But this would only work for standalone ports;
+ *    if bridged, this VLAN setup would break autonomous forwarding and would
+ *    force all switched traffic to pass through the CPU. So we must also make
+ *    the other front-panel ports members of this VID we're adding, albeit
+ *    we're not making it their PVID (they'll still have their own).
+ *    By the way - just because we're installing the same VID in multiple
+ *    switch ports doesn't mean that they'll start to talk to one another, even
+ *    while not bridged: the final forwarding decision is still an AND between
+ *    the L2 forwarding information (which is limiting forwarding in this case)
+ *    and the VLAN-based restrictions (of which there are none in this case,
+ *    since all ports are members).
+ *  - On TX (ingress from CPU and towards network) we are faced with a problem.
+ *    If we were to tag traffic (from within DSA) with the port's pvid, all
+ *    would be well, assuming the switch ports were standalone. Frames would
+ *    have no choice but to be directed towards the correct front-panel port.
+ *    But because we also want the RX VLAN to not break bridging, then
+ *    inevitably that means that we have to give them a choice (of what
+ *    front-panel port to go out on), and therefore we cannot steer traffic
+ *    based on the RX VID. So what we do is simply install one more VID on the
+ *    front-panel and CPU ports, and profit off of the fact that steering will
+ *    work just by virtue of the fact that there is only one other port that's
+ *    a member of the VID we're tagging the traffic with - the desired one.
+ *
+ * So at the end, each front-panel port will have one RX VID (also the PVID),
+ * the RX VID of all other front-panel ports, and one TX VID. Whereas the CPU
+ * port will have the RX and TX VIDs of all front-panel ports, and on top of
+ * that, is also tagged-input and tagged-output (VLAN trunk).
+ *
+ *               CPU port                               CPU port
+ * +-------------+-----+-------------+    +-------------+-----+-------------+
+ * |  RX VID     |     |             |    |  TX VID     |     |             |
+ * |  of swp0    |     |             |    |  of swp0    |     |             |
+ * |             +-----+             |    |             +-----+             |
+ * |                ^ T              |    |                | Tagged         |
+ * |                |                |    |                | ingress        |
+ * |    +-------+---+---+-------+    |    |    +-----------+                |
+ * |    |       |       |       |    |    |    | Untagged                   |
+ * |    |     U v     U v     U v    |    |    v egress                     |
+ * | +-----+ +-----+ +-----+ +-----+ |    | +-----+ +-----+ +-----+ +-----+ |
+ * | |     | |     | |     | |     | |    | |     | |     | |     | |     | |
+ * | |PVID | |     | |     | |     | |    | |     | |     | |     | |     | |
+ * +-+-----+-+-----+-+-----+-+-----+-+    +-+-----+-+-----+-+-----+-+-----+-+
+ *   swp0    swp1    swp2    swp3           swp0    swp1    swp2    swp3
+ */
+static int dsa_8021q_setup_port(struct dsa_8021q_context *ctx, int port,
+				bool enabled)
+{
+	int upstream = dsa_upstream_port(ctx->ds, port);
+	u16 rx_vid = dsa_8021q_rx_vid(ctx->ds, port);
+	u16 tx_vid = dsa_8021q_tx_vid(ctx->ds, port);
+	struct net_device *master;
+	int i, err, subvlan;
+
+	/* The CPU port is implicitly configured by
+	 * configuring the front-panel ports
+	 */
+	if (!dsa_is_user_port(ctx->ds, port))
+		return 0;
+
+	master = dsa_to_port(ctx->ds, port)->cpu_dp->master;
+
+	/* Add this user port's RX VID to the membership list of all others
+	 * (including itself). This is so that bridging will not be hindered.
+	 * L2 forwarding rules still take precedence when there are no VLAN
+	 * restrictions, so there are no concerns about leaking traffic.
+	 */
+	for (i = 0; i < ctx->ds->num_ports; i++) {
+		u16 flags;
+
+		if (i == upstream)
+			continue;
+		else if (i == port)
+			/* The RX VID is pvid on this port */
+			flags = BRIDGE_VLAN_INFO_UNTAGGED |
+				BRIDGE_VLAN_INFO_PVID;
+		else
+			/* The RX VID is a regular VLAN on all others */
+			flags = BRIDGE_VLAN_INFO_UNTAGGED;
+
+		err = dsa_8021q_vid_apply(ctx, i, rx_vid, flags, enabled);
+		if (err) {
+			dev_err(ctx->ds->dev,
+				"Failed to apply RX VID %d to port %d: %d\n",
+				rx_vid, port, err);
+			return err;
+		}
+	}
+
+	/* CPU port needs to see this port's RX VID
+	 * as tagged egress.
+	 */
+	err = dsa_8021q_vid_apply(ctx, upstream, rx_vid, 0, enabled);
+	if (err) {
+		dev_err(ctx->ds->dev,
+			"Failed to apply RX VID %d to port %d: %d\n",
+			rx_vid, port, err);
+		return err;
+	}
+
+	/* Add to the master's RX filter not only @rx_vid, but in fact
+	 * the entire subvlan range, just in case this DSA switch might
+	 * want to use sub-VLANs.
+	 */
+	for (subvlan = 0; subvlan < DSA_8021Q_N_SUBVLAN; subvlan++) {
+		u16 vid = dsa_8021q_rx_vid_subvlan(ctx->ds, port, subvlan);
+
+		if (enabled)
+			vlan_vid_add(master, ctx->proto, vid);
+		else
+			vlan_vid_del(master, ctx->proto, vid);
+	}
+
+	/* Finally apply the TX VID on this port and on the CPU port */
+	err = dsa_8021q_vid_apply(ctx, port, tx_vid, BRIDGE_VLAN_INFO_UNTAGGED,
+				  enabled);
+	if (err) {
+		dev_err(ctx->ds->dev,
+			"Failed to apply TX VID %d on port %d: %d\n",
+			tx_vid, port, err);
+		return err;
+	}
+	err = dsa_8021q_vid_apply(ctx, upstream, tx_vid, 0, enabled);
+	if (err) {
+		dev_err(ctx->ds->dev,
+			"Failed to apply TX VID %d on port %d: %d\n",
+			tx_vid, upstream, err);
+		return err;
+	}
+
+	return err;
+}
+
+int dsa_8021q_setup(struct dsa_8021q_context *ctx, bool enabled)
+{
+	int rc, port;
+
+	ASSERT_RTNL();
+
+	for (port = 0; port < ctx->ds->num_ports; port++) {
+		rc = dsa_8021q_setup_port(ctx, port, enabled);
+		if (rc < 0) {
+			dev_err(ctx->ds->dev,
+				"Failed to setup VLAN tagging for port %d: %d\n",
+				port, rc);
+			return rc;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_setup);
+
+static int dsa_8021q_crosschip_link_apply(struct dsa_8021q_context *ctx,
+					  int port,
+					  struct dsa_8021q_context *other_ctx,
+					  int other_port, bool enabled)
+{
+	u16 rx_vid = dsa_8021q_rx_vid(ctx->ds, port);
+
+	/* @rx_vid of local @ds port @port goes to @other_port of
+	 * @other_ds
+	 */
+	return dsa_8021q_vid_apply(other_ctx, other_port, rx_vid,
+				   BRIDGE_VLAN_INFO_UNTAGGED, enabled);
+}
+
+static int dsa_8021q_crosschip_link_add(struct dsa_8021q_context *ctx, int port,
+					struct dsa_8021q_context *other_ctx,
+					int other_port)
+{
+	struct dsa_8021q_crosschip_link *c;
+
+	list_for_each_entry(c, &ctx->crosschip_links, list) {
+		if (c->port == port && c->other_ctx == other_ctx &&
+		    c->other_port == other_port) {
+			refcount_inc(&c->refcount);
+			return 0;
+		}
+	}
+
+	dev_dbg(ctx->ds->dev,
+		"adding crosschip link from port %d to %s port %d\n",
+		port, dev_name(other_ctx->ds->dev), other_port);
+
+	c = kzalloc(sizeof(*c), GFP_KERNEL);
+	if (!c)
+		return -ENOMEM;
+
+	c->port = port;
+	c->other_ctx = other_ctx;
+	c->other_port = other_port;
+	refcount_set(&c->refcount, 1);
+
+	list_add(&c->list, &ctx->crosschip_links);
+
+	return 0;
+}
+
+static void dsa_8021q_crosschip_link_del(struct dsa_8021q_context *ctx,
+					 struct dsa_8021q_crosschip_link *c,
+					 bool *keep)
+{
+	*keep = !refcount_dec_and_test(&c->refcount);
+
+	if (*keep)
+		return;
+
+	dev_dbg(ctx->ds->dev,
+		"deleting crosschip link from port %d to %s port %d\n",
+		c->port, dev_name(c->other_ctx->ds->dev), c->other_port);
+
+	list_del(&c->list);
+	kfree(c);
+}
+
+/* Make traffic from local port @port be received by remote port @other_port.
+ * This means that our @rx_vid needs to be installed on @other_ds's upstream
+ * and user ports. The user ports should be egress-untagged so that they can
+ * pop the dsa_8021q VLAN. But the @other_upstream can be either egress-tagged
+ * or untagged: it doesn't matter, since it should never egress a frame having
+ * our @rx_vid.
+ */
+int dsa_8021q_crosschip_bridge_join(struct dsa_8021q_context *ctx, int port,
+				    struct dsa_8021q_context *other_ctx,
+				    int other_port)
+{
+	/* @other_upstream is how @other_ds reaches us. If we are part
+	 * of disjoint trees, then we are probably connected through
+	 * our CPU ports. If we're part of the same tree though, we should
+	 * probably use dsa_towards_port.
+	 */
+	int other_upstream = dsa_upstream_port(other_ctx->ds, other_port);
+	int rc;
+
+	rc = dsa_8021q_crosschip_link_add(ctx, port, other_ctx, other_port);
+	if (rc)
+		return rc;
+
+	rc = dsa_8021q_crosschip_link_apply(ctx, port, other_ctx,
+					    other_port, true);
+	if (rc)
+		return rc;
+
+	rc = dsa_8021q_crosschip_link_add(ctx, port, other_ctx, other_upstream);
+	if (rc)
+		return rc;
+
+	return dsa_8021q_crosschip_link_apply(ctx, port, other_ctx,
+					      other_upstream, true);
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_crosschip_bridge_join);
+
+int dsa_8021q_crosschip_bridge_leave(struct dsa_8021q_context *ctx, int port,
+				     struct dsa_8021q_context *other_ctx,
+				     int other_port)
+{
+	int other_upstream = dsa_upstream_port(other_ctx->ds, other_port);
+	struct dsa_8021q_crosschip_link *c, *n;
+
+	list_for_each_entry_safe(c, n, &ctx->crosschip_links, list) {
+		if (c->port == port && c->other_ctx == other_ctx &&
+		    (c->other_port == other_port ||
+		     c->other_port == other_upstream)) {
+			struct dsa_8021q_context *other_ctx = c->other_ctx;
+			int other_port = c->other_port;
+			bool keep;
+			int rc;
+
+			dsa_8021q_crosschip_link_del(ctx, c, &keep);
+			if (keep)
+				continue;
+
+			rc = dsa_8021q_crosschip_link_apply(ctx, port,
+							    other_ctx,
+							    other_port,
+							    false);
+			if (rc)
+				return rc;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dsa_8021q_crosschip_bridge_leave);
+
+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);
+
+MODULE_LICENSE("GPL v2");
diff --git a/net/dsa/tag_ar9331.c b/net/dsa/tag_ar9331.c
new file mode 100644
index 000000000..002cf7f95
--- /dev/null
+++ b/net/dsa/tag_ar9331.c
@@ -0,0 +1,93 @@
+// 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,
+				      struct packet_type *pt)
+{
+	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,
+	.overhead = 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..e934dace3
--- /dev/null
+++ b/net/dsa/tag_brcm.c
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Broadcom tag support
+ *
+ * Copyright (C) 2014 Broadcom Corporation
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "dsa_priv.h"
+
+/* This tag length is 4 bytes, older ones were 6 bytes, we do not
+ * handle them
+ */
+#define BRCM_TAG_LEN	4
+
+/* Tag is constructed and desconstructed 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)
+		memmove(skb->data, skb->data + BRCM_TAG_LEN, offset);
+
+	brcm_tag = skb->data + offset;
+
+	/* Set the ingress opcode, traffic class, tag enforcment 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,
+				       struct packet_type *pt,
+				       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);
+
+	skb->offload_fwd_mark = 1;
+
+	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 packet_type *pt)
+{
+	struct sk_buff *nskb;
+
+	/* skb->data points to the EtherType, the tag is right before it */
+	nskb = brcm_tag_rcv_ll(skb, dev, pt, 2);
+	if (!nskb)
+		return nskb;
+
+	/* Move the Ethernet DA and SA */
+	memmove(nskb->data - ETH_HLEN,
+		nskb->data - ETH_HLEN - BRCM_TAG_LEN,
+		2 * ETH_ALEN);
+
+	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,
+	.overhead = 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_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,
+					    struct packet_type *pt)
+{
+	/* tag is prepended to the packet */
+	return brcm_tag_rcv_ll(skb, dev, pt, 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,
+	.overhead = 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_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..63d690a0f
--- /dev/null
+++ b/net/dsa/tag_dsa.c
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * net/dsa/tag_dsa.c - (Non-ethertype) DSA tagging
+ * Copyright (c) 2008-2009 Marvell Semiconductor
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "dsa_priv.h"
+
+#define DSA_HLEN	4
+
+static struct sk_buff *dsa_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u8 *dsa_header;
+
+	/*
+	 * Convert the outermost 802.1q tag to a DSA tag for tagged
+	 * packets, or insert a DSA tag between the addresses and
+	 * the ethertype field for untagged packets.
+	 */
+	if (skb->protocol == htons(ETH_P_8021Q)) {
+		/*
+		 * Construct tagged FROM_CPU DSA tag from 802.1q tag.
+		 */
+		dsa_header = skb->data + 2 * ETH_ALEN;
+		dsa_header[0] = 0x60 | dp->ds->index;
+		dsa_header[1] = dp->index << 3;
+
+		/*
+		 * Move CFI field from byte 2 to byte 1.
+		 */
+		if (dsa_header[2] & 0x10) {
+			dsa_header[1] |= 0x01;
+			dsa_header[2] &= ~0x10;
+		}
+	} else {
+		skb_push(skb, DSA_HLEN);
+
+		memmove(skb->data, skb->data + DSA_HLEN, 2 * ETH_ALEN);
+
+		/*
+		 * Construct untagged FROM_CPU DSA tag.
+		 */
+		dsa_header = skb->data + 2 * ETH_ALEN;
+		dsa_header[0] = 0x40 | dp->ds->index;
+		dsa_header[1] = dp->index << 3;
+		dsa_header[2] = 0x00;
+		dsa_header[3] = 0x00;
+	}
+
+	return skb;
+}
+
+static struct sk_buff *dsa_rcv(struct sk_buff *skb, struct net_device *dev,
+			       struct packet_type *pt)
+{
+	u8 *dsa_header;
+	int source_device;
+	int source_port;
+
+	if (unlikely(!pskb_may_pull(skb, DSA_HLEN)))
+		return NULL;
+
+	/*
+	 * The ethertype field is part of the DSA header.
+	 */
+	dsa_header = skb->data - 2;
+
+	/*
+	 * Check that frame type is either TO_CPU or FORWARD.
+	 */
+	if ((dsa_header[0] & 0xc0) != 0x00 && (dsa_header[0] & 0xc0) != 0xc0)
+		return NULL;
+
+	/*
+	 * Determine source device and port.
+	 */
+	source_device = dsa_header[0] & 0x1f;
+	source_port = (dsa_header[1] >> 3) & 0x1f;
+
+	skb->dev = dsa_master_find_slave(dev, source_device, source_port);
+	if (!skb->dev)
+		return NULL;
+
+	/*
+	 * Convert the DSA header to an 802.1q header if the 'tagged'
+	 * bit in the DSA header is set.  If the 'tagged' bit is clear,
+	 * delete the DSA header entirely.
+	 */
+	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);
+	} else {
+		/*
+		 * Remove DSA tag and update checksum.
+		 */
+		skb_pull_rcsum(skb, DSA_HLEN);
+		memmove(skb->data - ETH_HLEN,
+			skb->data - ETH_HLEN - DSA_HLEN,
+			2 * ETH_ALEN);
+	}
+
+	skb->offload_fwd_mark = 1;
+
+	return skb;
+}
+
+static const struct dsa_device_ops dsa_netdev_ops = {
+	.name	= "dsa",
+	.proto	= DSA_TAG_PROTO_DSA,
+	.xmit	= dsa_xmit,
+	.rcv	= dsa_rcv,
+	.overhead = DSA_HLEN,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_DSA);
+
+module_dsa_tag_driver(dsa_netdev_ops);
diff --git a/net/dsa/tag_edsa.c b/net/dsa/tag_edsa.c
new file mode 100644
index 000000000..abf70a29d
--- /dev/null
+++ b/net/dsa/tag_edsa.c
@@ -0,0 +1,202 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * net/dsa/tag_edsa.c - Ethertype DSA tagging
+ * Copyright (c) 2008-2009 Marvell Semiconductor
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "dsa_priv.h"
+
+#define DSA_HLEN	4
+#define EDSA_HLEN	8
+
+#define FRAME_TYPE_TO_CPU	0x00
+#define FRAME_TYPE_FORWARD	0x03
+
+#define TO_CPU_CODE_MGMT_TRAP		0x00
+#define TO_CPU_CODE_FRAME2REG		0x01
+#define TO_CPU_CODE_IGMP_MLD_TRAP	0x02
+#define TO_CPU_CODE_POLICY_TRAP		0x03
+#define TO_CPU_CODE_ARP_MIRROR		0x04
+#define TO_CPU_CODE_POLICY_MIRROR	0x05
+
+static struct sk_buff *edsa_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	u8 *edsa_header;
+
+	/*
+	 * Convert the outermost 802.1q tag to a DSA tag and prepend
+	 * a DSA ethertype field is the packet is tagged, or insert
+	 * a DSA ethertype plus DSA tag between the addresses and the
+	 * current ethertype field if the packet is untagged.
+	 */
+	if (skb->protocol == htons(ETH_P_8021Q)) {
+		skb_push(skb, DSA_HLEN);
+
+		memmove(skb->data, skb->data + DSA_HLEN, 2 * ETH_ALEN);
+
+		/*
+		 * Construct tagged FROM_CPU DSA tag from 802.1q tag.
+		 */
+		edsa_header = skb->data + 2 * ETH_ALEN;
+		edsa_header[0] = (ETH_P_EDSA >> 8) & 0xff;
+		edsa_header[1] = ETH_P_EDSA & 0xff;
+		edsa_header[2] = 0x00;
+		edsa_header[3] = 0x00;
+		edsa_header[4] = 0x60 | dp->ds->index;
+		edsa_header[5] = dp->index << 3;
+
+		/*
+		 * Move CFI field from byte 6 to byte 5.
+		 */
+		if (edsa_header[6] & 0x10) {
+			edsa_header[5] |= 0x01;
+			edsa_header[6] &= ~0x10;
+		}
+	} else {
+		skb_push(skb, EDSA_HLEN);
+
+		memmove(skb->data, skb->data + EDSA_HLEN, 2 * ETH_ALEN);
+
+		/*
+		 * Construct untagged FROM_CPU DSA tag.
+		 */
+		edsa_header = skb->data + 2 * ETH_ALEN;
+		edsa_header[0] = (ETH_P_EDSA >> 8) & 0xff;
+		edsa_header[1] = ETH_P_EDSA & 0xff;
+		edsa_header[2] = 0x00;
+		edsa_header[3] = 0x00;
+		edsa_header[4] = 0x40 | dp->ds->index;
+		edsa_header[5] = dp->index << 3;
+		edsa_header[6] = 0x00;
+		edsa_header[7] = 0x00;
+	}
+
+	return skb;
+}
+
+static struct sk_buff *edsa_rcv(struct sk_buff *skb, struct net_device *dev,
+				struct packet_type *pt)
+{
+	u8 *edsa_header;
+	int frame_type;
+	int code;
+	int source_device;
+	int source_port;
+
+	if (unlikely(!pskb_may_pull(skb, EDSA_HLEN)))
+		return NULL;
+
+	/*
+	 * Skip the two null bytes after the ethertype.
+	 */
+	edsa_header = skb->data + 2;
+
+	/*
+	 * Check that frame type is either TO_CPU or FORWARD.
+	 */
+	frame_type = edsa_header[0] >> 6;
+
+	switch (frame_type) {
+	case FRAME_TYPE_TO_CPU:
+		code = (edsa_header[1] & 0x6) | ((edsa_header[2] >> 4) & 1);
+
+		/*
+		 * Mark the frame to never egress on any port of the same switch
+		 * unless it's a trapped IGMP/MLD packet, in which case the
+		 * bridge might want to forward it.
+		 */
+		if (code != TO_CPU_CODE_IGMP_MLD_TRAP)
+			skb->offload_fwd_mark = 1;
+
+		break;
+
+	case FRAME_TYPE_FORWARD:
+		skb->offload_fwd_mark = 1;
+		break;
+
+	default:
+		return NULL;
+	}
+
+	/*
+	 * Determine source device and port.
+	 */
+	source_device = edsa_header[0] & 0x1f;
+	source_port = (edsa_header[1] >> 3) & 0x1f;
+
+	skb->dev = dsa_master_find_slave(dev, source_device, source_port);
+	if (!skb->dev)
+		return NULL;
+
+	/*
+	 * If the 'tagged' bit is set, convert the DSA tag to a 802.1q
+	 * tag and delete the ethertype part.  If the 'tagged' bit is
+	 * clear, delete the ethertype and the DSA tag parts.
+	 */
+	if (edsa_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] = edsa_header[2] & ~0x10;
+		new_header[3] = edsa_header[3];
+
+		/*
+		 * Move CFI bit from its place in the DSA header to
+		 * its 802.1q-designated place.
+		 */
+		if (edsa_header[1] & 0x01)
+			new_header[2] |= 0x10;
+
+		skb_pull_rcsum(skb, DSA_HLEN);
+
+		/*
+		 * 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(edsa_header + 2, 2, 0));
+			skb->csum = c;
+		}
+
+		memcpy(edsa_header, new_header, DSA_HLEN);
+
+		memmove(skb->data - ETH_HLEN,
+			skb->data - ETH_HLEN - DSA_HLEN,
+			2 * ETH_ALEN);
+	} else {
+		/*
+		 * Remove DSA tag and update checksum.
+		 */
+		skb_pull_rcsum(skb, EDSA_HLEN);
+		memmove(skb->data - ETH_HLEN,
+			skb->data - ETH_HLEN - EDSA_HLEN,
+			2 * ETH_ALEN);
+	}
+
+	return skb;
+}
+
+static const struct dsa_device_ops edsa_netdev_ops = {
+	.name	= "edsa",
+	.proto	= DSA_TAG_PROTO_EDSA,
+	.xmit	= edsa_xmit,
+	.rcv	= edsa_rcv,
+	.overhead = EDSA_HLEN,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_EDSA);
+
+module_dsa_tag_driver(edsa_netdev_ops);
diff --git a/net/dsa/tag_gswip.c b/net/dsa/tag_gswip.c
new file mode 100644
index 000000000..2f5bd5e33
--- /dev/null
+++ b/net/dsa/tag_gswip.c
@@ -0,0 +1,112 @@
+// 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,
+				     struct packet_type *pt)
+{
+	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,
+	.overhead = 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_ksz.c b/net/dsa/tag_ksz.c
new file mode 100644
index 000000000..230ddf45d
--- /dev/null
+++ b/net/dsa/tag_ksz.c
@@ -0,0 +1,202 @@
+// 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 <linux/slab.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;
+
+	skb->offload_fwd_mark = true;
+
+	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;
+
+	/* 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,
+				  struct packet_type *pt)
+{
+	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,
+	.overhead = KSZ_INGRESS_TAG_LEN,
+	.tail_tag = true,
+};
+
+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;
+
+	/* 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,
+				   struct packet_type *pt)
+{
+	/* 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,
+	.overhead = KSZ9477_INGRESS_TAG_LEN,
+	.tail_tag = true,
+};
+
+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;
+
+	/* 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,
+	.overhead = KSZ_INGRESS_TAG_LEN,
+	.tail_tag = true,
+};
+
+DSA_TAG_DRIVER(ksz9893_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893);
+
+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),
+};
+
+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..aa1318dcc
--- /dev/null
+++ b/net/dsa/tag_lan9303.c
@@ -0,0 +1,134 @@
+// 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 */
+	memmove(skb->data, skb->data + LAN9303_TAG_LEN, 2 * ETH_ALEN);
+
+	lan9303_tag = (__be16 *)(skb->data + 2 * ETH_ALEN);
+	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,
+				   struct packet_type *pt)
+{
+	__be16 *lan9303_tag;
+	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;
+	}
+
+	/* '->data' points into the middle of our special VLAN tag information:
+	 *
+	 * ~ MAC src   | 0x81 | 0x00 | 0xyy | 0xzz | ether type
+	 *                           ^
+	 *                        ->data
+	 */
+	lan9303_tag = (__be16 *)(skb->data - 2);
+
+	if (lan9303_tag[0] != htons(ETH_P_8021Q)) {
+		dev_warn_ratelimited(&dev->dev, "Dropping packet due to invalid VLAN marker\n");
+		return NULL;
+	}
+
+	lan9303_tag1 = ntohs(lan9303_tag[1]);
+	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;
+	}
+
+	/* remove the special VLAN tag between the MAC addresses
+	 * and the current ethertype field.
+	 */
+	skb_pull_rcsum(skb, 2 + 2);
+	memmove(skb->data - ETH_HLEN, skb->data - (ETH_HLEN + LAN9303_TAG_LEN),
+		2 * ETH_ALEN);
+	skb->offload_fwd_mark = !(lan9303_tag1 & LAN9303_TAG_RX_TRAPPED_TO_CPU);
+
+	return skb;
+}
+
+static const struct dsa_device_ops lan9303_netdev_ops = {
+	.name = "lan9303",
+	.proto	= DSA_TAG_PROTO_LAN9303,
+	.xmit = lan9303_xmit,
+	.rcv = lan9303_rcv,
+	.overhead = 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..597484876
--- /dev/null
+++ b/net/dsa/tag_mtk.c
@@ -0,0 +1,123 @@
+// 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;
+	unsigned char *dest = eth_hdr(skb)->h_dest;
+	bool is_multicast_skb = is_multicast_ether_addr(dest) &&
+				!is_broadcast_ether_addr(dest);
+
+	/* 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);
+		memmove(skb->data, skb->data + MTK_HDR_LEN, 2 * ETH_ALEN);
+	}
+
+	mtk_tag = skb->data + 2 * ETH_ALEN;
+
+	/* 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;
+
+	/* Disable SA learning for multicast frames */
+	if (unlikely(is_multicast_skb))
+		mtk_tag[1] |= MTK_HDR_XMIT_SA_DIS;
+
+	/* 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,
+				   struct packet_type *pt)
+{
+	u16 hdr;
+	int port;
+	__be16 *phdr;
+	unsigned char *dest = eth_hdr(skb)->h_dest;
+	bool is_multicast_skb = is_multicast_ether_addr(dest) &&
+				!is_broadcast_ether_addr(dest);
+
+	if (unlikely(!pskb_may_pull(skb, MTK_HDR_LEN)))
+		return NULL;
+
+	/* The MTK header is added by the switch between src addr
+	 * and ethertype at this point, skb->data points to 2 bytes
+	 * after src addr so header should be 2 bytes right before.
+	 */
+	phdr = (__be16 *)(skb->data - 2);
+	hdr = ntohs(*phdr);
+
+	/* Remove MTK tag and recalculate checksum. */
+	skb_pull_rcsum(skb, MTK_HDR_LEN);
+
+	memmove(skb->data - ETH_HLEN,
+		skb->data - ETH_HLEN - MTK_HDR_LEN,
+		2 * ETH_ALEN);
+
+	/* 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;
+
+	/* Only unicast or broadcast frames are offloaded */
+	if (likely(!is_multicast_skb))
+		skb->offload_fwd_mark = 1;
+
+	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,
+	.overhead	= 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..16a1afd5b
--- /dev/null
+++ b/net/dsa/tag_ocelot.c
@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2019 NXP Semiconductors
+ */
+#include <soc/mscc/ocelot.h>
+#include <linux/packing.h>
+#include "dsa_priv.h"
+
+/* The CPU injection header and the CPU extraction header can have 3 types of
+ * prefixes: long, short and no prefix. The format of the header itself is the
+ * same in all 3 cases.
+ *
+ * Extraction with long prefix:
+ *
+ * +-------------------+-------------------+------+------+------------+-------+
+ * | ff:ff:ff:ff:ff:ff | ff:ff:ff:ff:ff:ff | 8880 | 000a | extraction | frame |
+ * |                   |                   |      |      |   header   |       |
+ * +-------------------+-------------------+------+------+------------+-------+
+ *        48 bits             48 bits      16 bits 16 bits  128 bits
+ *
+ * Extraction with short prefix:
+ *
+ *                                         +------+------+------------+-------+
+ *                                         | 8880 | 000a | extraction | frame |
+ *                                         |      |      |   header   |       |
+ *                                         +------+------+------------+-------+
+ *                                         16 bits 16 bits  128 bits
+ *
+ * Extraction with no prefix:
+ *
+ *                                                       +------------+-------+
+ *                                                       | extraction | frame |
+ *                                                       |   header   |       |
+ *                                                       +------------+-------+
+ *                                                          128 bits
+ *
+ *
+ * Injection with long prefix:
+ *
+ * +-------------------+-------------------+------+------+------------+-------+
+ * |      any dmac     |      any smac     | 8880 | 000a | injection  | frame |
+ * |                   |                   |      |      |   header   |       |
+ * +-------------------+-------------------+------+------+------------+-------+
+ *        48 bits             48 bits      16 bits 16 bits  128 bits
+ *
+ * Injection with short prefix:
+ *
+ *                                         +------+------+------------+-------+
+ *                                         | 8880 | 000a | injection  | frame |
+ *                                         |      |      |   header   |       |
+ *                                         +------+------+------------+-------+
+ *                                         16 bits 16 bits  128 bits
+ *
+ * Injection with no prefix:
+ *
+ *                                                       +------------+-------+
+ *                                                       | injection  | frame |
+ *                                                       |   header   |       |
+ *                                                       +------------+-------+
+ *                                                          128 bits
+ *
+ * The injection header looks like this (network byte order, bit 127
+ * is part of lowest address byte in memory, bit 0 is part of highest
+ * address byte):
+ *
+ *         +------+------+------+------+------+------+------+------+
+ * 127:120 |BYPASS| MASQ |          MASQ_PORT        |REW_OP|REW_OP|
+ *         +------+------+------+------+------+------+------+------+
+ * 119:112 |                         REW_OP                        |
+ *         +------+------+------+------+------+------+------+------+
+ * 111:104 |                         REW_VAL                       |
+ *         +------+------+------+------+------+------+------+------+
+ * 103: 96 |                         REW_VAL                       |
+ *         +------+------+------+------+------+------+------+------+
+ *  95: 88 |                         REW_VAL                       |
+ *         +------+------+------+------+------+------+------+------+
+ *  87: 80 |                         REW_VAL                       |
+ *         +------+------+------+------+------+------+------+------+
+ *  79: 72 |                          RSV                          |
+ *         +------+------+------+------+------+------+------+------+
+ *  71: 64 |            RSV            |           DEST            |
+ *         +------+------+------+------+------+------+------+------+
+ *  63: 56 |                         DEST                          |
+ *         +------+------+------+------+------+------+------+------+
+ *  55: 48 |                          RSV                          |
+ *         +------+------+------+------+------+------+------+------+
+ *  47: 40 |  RSV |         SRC_PORT          |     RSV     |TFRM_TIMER|
+ *         +------+------+------+------+------+------+------+------+
+ *  39: 32 |     TFRM_TIMER     |               RSV                |
+ *         +------+------+------+------+------+------+------+------+
+ *  31: 24 |  RSV |  DP  |   POP_CNT   |           CPUQ            |
+ *         +------+------+------+------+------+------+------+------+
+ *  23: 16 |           CPUQ            |      QOS_CLASS     |TAG_TYPE|
+ *         +------+------+------+------+------+------+------+------+
+ *  15:  8 |         PCP        |  DEI |            VID            |
+ *         +------+------+------+------+------+------+------+------+
+ *   7:  0 |                          VID                          |
+ *         +------+------+------+------+------+------+------+------+
+ *
+ * And the extraction header looks like this:
+ *
+ *         +------+------+------+------+------+------+------+------+
+ * 127:120 |  RSV |                  REW_OP                        |
+ *         +------+------+------+------+------+------+------+------+
+ * 119:112 |       REW_OP       |              REW_VAL             |
+ *         +------+------+------+------+------+------+------+------+
+ * 111:104 |                         REW_VAL                       |
+ *         +------+------+------+------+------+------+------+------+
+ * 103: 96 |                         REW_VAL                       |
+ *         +------+------+------+------+------+------+------+------+
+ *  95: 88 |                         REW_VAL                       |
+ *         +------+------+------+------+------+------+------+------+
+ *  87: 80 |       REW_VAL      |               LLEN               |
+ *         +------+------+------+------+------+------+------+------+
+ *  79: 72 | LLEN |                      WLEN                      |
+ *         +------+------+------+------+------+------+------+------+
+ *  71: 64 | WLEN |                      RSV                       |
+ *         +------+------+------+------+------+------+------+------+
+ *  63: 56 |                          RSV                          |
+ *         +------+------+------+------+------+------+------+------+
+ *  55: 48 |                          RSV                          |
+ *         +------+------+------+------+------+------+------+------+
+ *  47: 40 | RSV  |          SRC_PORT         |       ACL_ID       |
+ *         +------+------+------+------+------+------+------+------+
+ *  39: 32 |       ACL_ID       |  RSV |         SFLOW_ID          |
+ *         +------+------+------+------+------+------+------+------+
+ *  31: 24 |ACL_HIT| DP  |  LRN_FLAGS  |           CPUQ            |
+ *         +------+------+------+------+------+------+------+------+
+ *  23: 16 |           CPUQ            |      QOS_CLASS     |TAG_TYPE|
+ *         +------+------+------+------+------+------+------+------+
+ *  15:  8 |         PCP        |  DEI |            VID            |
+ *         +------+------+------+------+------+------+------+------+
+ *   7:  0 |                          VID                          |
+ *         +------+------+------+------+------+------+------+------+
+ */
+
+static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
+				   struct net_device *netdev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(netdev);
+	struct sk_buff *clone = DSA_SKB_CB(skb)->clone;
+	struct dsa_switch *ds = dp->ds;
+	struct ocelot *ocelot = ds->priv;
+	struct ocelot_port *ocelot_port;
+	u8 *prefix, *injection;
+	u64 qos_class, rew_op;
+
+	ocelot_port = ocelot->ports[dp->index];
+
+	injection = skb_push(skb, OCELOT_TAG_LEN);
+
+	prefix = skb_push(skb, OCELOT_SHORT_PREFIX_LEN);
+
+	memcpy(prefix, ocelot_port->xmit_template, OCELOT_TOTAL_TAG_LEN);
+
+	/* Fix up the fields which are not statically determined
+	 * in the template
+	 */
+	qos_class = skb->priority;
+	packing(injection, &qos_class, 19,  17, OCELOT_TAG_LEN, PACK, 0);
+
+	/* TX timestamping was requested */
+	if (clone) {
+		rew_op = ocelot_port->ptp_cmd;
+		/* Retrieve timestamp ID populated inside skb->cb[0] of the
+		 * clone by ocelot_port_add_txtstamp_skb
+		 */
+		if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP)
+			rew_op |= clone->cb[0] << 3;
+
+		packing(injection, &rew_op, 125, 117, OCELOT_TAG_LEN, PACK, 0);
+	}
+
+	return skb;
+}
+
+static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
+				  struct net_device *netdev,
+				  struct packet_type *pt)
+{
+	struct dsa_port *cpu_dp = netdev->dsa_ptr;
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct ocelot *ocelot = ds->priv;
+	u64 src_port, qos_class;
+	u64 vlan_tci, tag_type;
+	u8 *start = skb->data;
+	u8 *extraction;
+	u16 vlan_tpid;
+
+	/* 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);
+
+	packing(extraction, &src_port,  46, 43, OCELOT_TAG_LEN, UNPACK, 0);
+	packing(extraction, &qos_class, 19, 17, OCELOT_TAG_LEN, UNPACK, 0);
+	packing(extraction, &tag_type,  16, 16, OCELOT_TAG_LEN, UNPACK, 0);
+	packing(extraction, &vlan_tci,  15,  0, OCELOT_TAG_LEN, UNPACK, 0);
+
+	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;
+
+	skb->offload_fwd_mark = 1;
+	skb->priority = qos_class;
+
+	/* 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.
+	 */
+	vlan_tpid = tag_type ? ETH_P_8021AD : ETH_P_8021Q;
+
+	if (ocelot->ports[src_port]->vlan_aware &&
+	    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,
+	.overhead		= OCELOT_TOTAL_TAG_LEN,
+	.promisc_on_master	= true,
+};
+
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT);
+
+module_dsa_tag_driver(ocelot_netdev_ops);
diff --git a/net/dsa/tag_qca.c b/net/dsa/tag_qca.c
new file mode 100644
index 000000000..88181b52f
--- /dev/null
+++ b/net/dsa/tag_qca.c
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2015, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/etherdevice.h>
+
+#include "dsa_priv.h"
+
+#define QCA_HDR_LEN	2
+#define QCA_HDR_VERSION	0x2
+
+#define QCA_HDR_RECV_VERSION_MASK	GENMASK(15, 14)
+#define QCA_HDR_RECV_VERSION_S		14
+#define QCA_HDR_RECV_PRIORITY_MASK	GENMASK(13, 11)
+#define QCA_HDR_RECV_PRIORITY_S		11
+#define QCA_HDR_RECV_TYPE_MASK		GENMASK(10, 6)
+#define QCA_HDR_RECV_TYPE_S		6
+#define QCA_HDR_RECV_FRAME_IS_TAGGED	BIT(3)
+#define QCA_HDR_RECV_SOURCE_PORT_MASK	GENMASK(2, 0)
+
+#define QCA_HDR_XMIT_VERSION_MASK	GENMASK(15, 14)
+#define QCA_HDR_XMIT_VERSION_S		14
+#define QCA_HDR_XMIT_PRIORITY_MASK	GENMASK(13, 11)
+#define QCA_HDR_XMIT_PRIORITY_S		11
+#define QCA_HDR_XMIT_CONTROL_MASK	GENMASK(10, 8)
+#define QCA_HDR_XMIT_CONTROL_S		8
+#define QCA_HDR_XMIT_FROM_CPU		BIT(7)
+#define QCA_HDR_XMIT_DP_BIT_MASK	GENMASK(6, 0)
+
+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);
+
+	memmove(skb->data, skb->data + QCA_HDR_LEN, 2 * ETH_ALEN);
+	phdr = (__be16 *)(skb->data + 2 * ETH_ALEN);
+
+	/* Set the version field, and set destination port information */
+	hdr = QCA_HDR_VERSION << QCA_HDR_XMIT_VERSION_S |
+		QCA_HDR_XMIT_FROM_CPU | BIT(dp->index);
+
+	*phdr = htons(hdr);
+
+	return skb;
+}
+
+static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev,
+				   struct packet_type *pt)
+{
+	u8 ver;
+	u16  hdr;
+	int port;
+	__be16 *phdr;
+
+	if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN)))
+		return NULL;
+
+	/* The QCA header is added by the switch between src addr and Ethertype
+	 * At this point, skb->data points to ethertype so header should be
+	 * right before
+	 */
+	phdr = (__be16 *)(skb->data - 2);
+	hdr = ntohs(*phdr);
+
+	/* Make sure the version is correct */
+	ver = (hdr & QCA_HDR_RECV_VERSION_MASK) >> QCA_HDR_RECV_VERSION_S;
+	if (unlikely(ver != QCA_HDR_VERSION))
+		return NULL;
+
+	/* Remove QCA tag and recalculate checksum */
+	skb_pull_rcsum(skb, QCA_HDR_LEN);
+	memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - QCA_HDR_LEN,
+		ETH_HLEN - QCA_HDR_LEN);
+
+	/* Get source port information */
+	port = (hdr & QCA_HDR_RECV_SOURCE_PORT_MASK);
+
+	skb->dev = dsa_master_find_slave(dev, 0, port);
+	if (!skb->dev)
+		return NULL;
+
+	return skb;
+}
+
+static const struct dsa_device_ops qca_netdev_ops = {
+	.name	= "qca",
+	.proto	= DSA_TAG_PROTO_QCA,
+	.xmit	= qca_tag_xmit,
+	.rcv	= qca_tag_rcv,
+	.overhead = QCA_HDR_LEN,
+};
+
+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..24375ebd6
--- /dev/null
+++ b/net/dsa/tag_rtl4_a.c
@@ -0,0 +1,133 @@
+// 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);
+
+	memmove(skb->data, skb->data + RTL4_A_HDR_LEN, 2 * ETH_ALEN);
+	tag = skb->data + 2 * ETH_ALEN;
+
+	/* Set Ethertype */
+	p = (__be16 *)tag;
+	*p = htons(RTL4_A_ETHERTYPE);
+
+	out = (RTL4_A_PROTOCOL_RTL8366RB << RTL4_A_PROTOCOL_SHIFT) | (2 << 8);
+	/* 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,
+				     struct packet_type *pt)
+{
+	u16 protport;
+	__be16 *p;
+	u16 etype;
+	u8 *tag;
+	u8 prot;
+	u8 port;
+
+	if (unlikely(!pskb_may_pull(skb, RTL4_A_HDR_LEN)))
+		return NULL;
+
+	/* The RTL4 header has its own custom Ethertype 0x8899 and that
+	 * starts right at the beginning of the packet, after the src
+	 * ethernet addr. Apparantly skb->data always points 2 bytes in,
+	 * behind the Ethertype.
+	 */
+	tag = skb->data - 2;
+	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);
+
+	/* Move ethernet DA and SA in front of the data */
+	memmove(skb->data - ETH_HLEN,
+		skb->data - ETH_HLEN - RTL4_A_HDR_LEN,
+		2 * ETH_ALEN);
+
+	skb->offload_fwd_mark = 1;
+
+	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,
+	.overhead = 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_sja1105.c b/net/dsa/tag_sja1105.c
new file mode 100644
index 000000000..07876160e
--- /dev/null
+++ b/net/dsa/tag_sja1105.c
@@ -0,0 +1,373 @@
+// 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"
+
+/* 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;
+}
+
+static bool sja1105_can_use_vlan_as_tags(const struct sk_buff *skb)
+{
+	struct vlan_ethhdr *hdr = vlan_eth_hdr(skb);
+	u16 vlan_tci;
+
+	if (hdr->h_vlan_proto == htons(ETH_P_SJA1105))
+		return true;
+
+	if (hdr->h_vlan_proto != htons(ETH_P_8021Q) &&
+	    !skb_vlan_tag_present(skb))
+		return false;
+
+	if (skb_vlan_tag_present(skb))
+		vlan_tci = skb_vlan_tag_get(skb);
+	else
+		vlan_tci = ntohs(hdr->h_vlan_TCI);
+
+	return vid_is_dsa_8021q(vlan_tci & VLAN_VID_MASK);
+}
+
+/* This is the first time the tagger sees the frame on RX.
+ * Figure out if we can decode it.
+ */
+static bool sja1105_filter(const struct sk_buff *skb, struct net_device *dev)
+{
+	if (sja1105_can_use_vlan_as_tags(skb))
+		return true;
+	if (sja1105_is_link_local(skb))
+		return true;
+	if (sja1105_is_meta_frame(skb))
+		return true;
+	return false;
+}
+
+/* Calls sja1105_port_deferred_xmit in sja1105_main.c */
+static struct sk_buff *sja1105_defer_xmit(struct sja1105_port *sp,
+					  struct sk_buff *skb)
+{
+	/* Increase refcount so the kfree_skb in dsa_slave_xmit
+	 * won't really free the packet.
+	 */
+	skb_queue_tail(&sp->xmit_queue, skb_get(skb));
+	kthread_queue_work(sp->xmit_worker, &sp->xmit_work);
+
+	return NULL;
+}
+
+static u16 sja1105_xmit_tpid(struct sja1105_port *sp)
+{
+	return sp->xmit_tpid;
+}
+
+static struct sk_buff *sja1105_xmit(struct sk_buff *skb,
+				    struct net_device *netdev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(netdev);
+	u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index);
+	u16 queue_mapping = skb_get_queue_mapping(skb);
+	u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
+
+	/* 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)))
+		return sja1105_defer_xmit(dp->priv, skb);
+
+	return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp->priv),
+			     ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
+}
+
+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)->meta_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)
+{
+	struct sja1105_port *sp;
+	struct dsa_port *dp;
+
+	dp = dsa_slave_to_port(skb->dev);
+	sp = dp->priv;
+
+	/* Step 1: A timestampable frame was received.
+	 * Buffer it until we get its meta frame.
+	 */
+	if (is_link_local) {
+		if (!test_bit(SJA1105_HWTS_RX_EN, &sp->data->state))
+			/* Do normal processing. */
+			return skb;
+
+		spin_lock(&sp->data->meta_lock);
+		/* Was this a link-local frame instead of the meta
+		 * that we were expecting?
+		 */
+		if (sp->data->stampable_skb) {
+			dev_err_ratelimited(dp->ds->dev,
+					    "Expected meta frame, is %12llx "
+					    "in the DSA master multicast filter?\n",
+					    SJA1105_META_DMAC);
+			kfree_skb(sp->data->stampable_skb);
+		}
+
+		/* Hold a reference to avoid dsa_switch_rcv
+		 * from freeing the skb.
+		 */
+		sp->data->stampable_skb = skb_get(skb);
+		spin_unlock(&sp->data->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 sk_buff *stampable_skb;
+
+		/* Drop the meta frame if we're not in the right state
+		 * to process it.
+		 */
+		if (!test_bit(SJA1105_HWTS_RX_EN, &sp->data->state))
+			return NULL;
+
+		spin_lock(&sp->data->meta_lock);
+
+		stampable_skb = sp->data->stampable_skb;
+		sp->data->stampable_skb = NULL;
+
+		/* Was this a meta frame instead of the link-local
+		 * that we were expecting?
+		 */
+		if (!stampable_skb) {
+			dev_err_ratelimited(dp->ds->dev,
+					    "Unexpected meta frame\n");
+			spin_unlock(&sp->data->meta_lock);
+			return NULL;
+		}
+
+		if (stampable_skb->dev != skb->dev) {
+			dev_err_ratelimited(dp->ds->dev,
+					    "Meta frame on wrong port\n");
+			spin_unlock(&sp->data->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(&sp->data->meta_lock);
+	}
+
+	return skb;
+}
+
+static void sja1105_decode_subvlan(struct sk_buff *skb, u16 subvlan)
+{
+	struct dsa_port *dp = dsa_slave_to_port(skb->dev);
+	struct sja1105_port *sp = dp->priv;
+	u16 vid = sp->subvlan_map[subvlan];
+	u16 vlan_tci;
+
+	if (vid == VLAN_N_VID)
+		return;
+
+	vlan_tci = (skb->priority << VLAN_PRIO_SHIFT) | vid;
+	__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tci);
+}
+
+static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
+				   struct net_device *netdev,
+				   struct packet_type *pt)
+{
+	struct sja1105_meta meta = {0};
+	int source_port, switch_id;
+	struct ethhdr *hdr;
+	u16 tpid, vid, tci;
+	bool is_link_local;
+	u16 subvlan = 0;
+	bool is_tagged;
+	bool is_meta;
+
+	hdr = eth_hdr(skb);
+	tpid = ntohs(hdr->h_proto);
+	is_tagged = (tpid == ETH_P_SJA1105 || tpid == ETH_P_8021Q ||
+		     skb_vlan_tag_present(skb));
+	is_link_local = sja1105_is_link_local(skb);
+	is_meta = sja1105_is_meta_frame(skb);
+
+	skb->offload_fwd_mark = 1;
+
+	if (is_tagged) {
+		/* Normal traffic path. */
+		skb_push_rcsum(skb, ETH_HLEN);
+		if (skb_vlan_tag_present(skb)) {
+			tci = skb_vlan_tag_get(skb);
+			__vlan_hwaccel_clear_tag(skb);
+		} else {
+			__skb_vlan_pop(skb, &tci);
+		}
+		skb_pull_rcsum(skb, ETH_HLEN);
+		skb_reset_network_header(skb);
+		skb_reset_transport_header(skb);
+
+		vid = tci & VLAN_VID_MASK;
+		source_port = dsa_8021q_rx_source_port(vid);
+		switch_id = dsa_8021q_rx_switch_id(vid);
+		skb->priority = (tci & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
+		subvlan = dsa_8021q_rx_subvlan(vid);
+	} else 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];
+		/* Clear the DMAC bytes that were mangled by the switch */
+		hdr->h_dest[3] = 0;
+		hdr->h_dest[4] = 0;
+	} else if (is_meta) {
+		sja1105_meta_unpack(skb, &meta);
+		source_port = meta.source_port;
+		switch_id = meta.switch_id;
+	} else {
+		return NULL;
+	}
+
+	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 (subvlan)
+		sja1105_decode_subvlan(skb, subvlan);
+
+	return sja1105_rcv_meta_state_machine(skb, &meta, is_link_local,
+					      is_meta);
+}
+
+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 const struct dsa_device_ops sja1105_netdev_ops = {
+	.name = "sja1105",
+	.proto = DSA_TAG_PROTO_SJA1105,
+	.xmit = sja1105_xmit,
+	.rcv = sja1105_rcv,
+	.filter = sja1105_filter,
+	.overhead = VLAN_HLEN,
+	.flow_dissect = sja1105_flow_dissect,
+	.promisc_on_master = true,
+};
+
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1105);
+
+module_dsa_tag_driver(sja1105_netdev_ops);
diff --git a/net/dsa/tag_trailer.c b/net/dsa/tag_trailer.c
new file mode 100644
index 000000000..5b97ede56
--- /dev/null
+++ b/net/dsa/tag_trailer.c
@@ -0,0 +1,65 @@
+// 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,
+				   struct packet_type *pt)
+{
+	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,
+	.overhead = 4,
+	.tail_tag = true,
+};
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_TRAILER);
+
+module_dsa_tag_driver(trailer_netdev_ops);