1 files changed, 100 insertions, 0 deletions
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);