--- /dev/null
+From 964dbf186eaa84d409c359ddf09c827a3fbe8228 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com>
+Date: Wed, 17 Mar 2021 11:29:26 +0100
+Subject: [PATCH] net: dsa: tag_brcm: add support for legacy tags
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Add support for legacy Broadcom tags, which are similar to DSA_TAG_PROTO_BRCM.
+These tags are used on BCM5325, BCM5365 and BCM63xx switches.
+
+Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ include/net/dsa.h | 2 +
+ net/dsa/Kconfig | 7 +++
+ net/dsa/tag_brcm.c | 107 +++++++++++++++++++++++++++++++++++++++++++--
+ 3 files changed, 113 insertions(+), 3 deletions(-)
+
+--- a/include/net/dsa.h
++++ b/include/net/dsa.h
+@@ -45,10 +45,12 @@ struct phylink_link_state;
+ #define DSA_TAG_PROTO_OCELOT_VALUE 15
+ #define DSA_TAG_PROTO_AR9331_VALUE 16
+ #define DSA_TAG_PROTO_RTL4_A_VALUE 17
++#define DSA_TAG_PROTO_BRCM_LEGACY_VALUE 22
+
+ enum dsa_tag_protocol {
+ DSA_TAG_PROTO_NONE = DSA_TAG_PROTO_NONE_VALUE,
+ DSA_TAG_PROTO_BRCM = DSA_TAG_PROTO_BRCM_VALUE,
++ DSA_TAG_PROTO_BRCM_LEGACY = DSA_TAG_PROTO_BRCM_LEGACY_VALUE,
+ DSA_TAG_PROTO_BRCM_PREPEND = DSA_TAG_PROTO_BRCM_PREPEND_VALUE,
+ DSA_TAG_PROTO_DSA = DSA_TAG_PROTO_DSA_VALUE,
+ DSA_TAG_PROTO_EDSA = DSA_TAG_PROTO_EDSA_VALUE,
+--- a/net/dsa/Kconfig
++++ b/net/dsa/Kconfig
+@@ -47,6 +47,13 @@ config NET_DSA_TAG_BRCM
+ Say Y if you want to enable support for tagging frames for the
+ Broadcom switches which place the tag after the MAC source address.
+
++config NET_DSA_TAG_BRCM_LEGACY
++ tristate "Tag driver for Broadcom legacy switches using in-frame headers"
++ select NET_DSA_TAG_BRCM_COMMON
++ help
++ Say Y if you want to enable support for tagging frames for the
++ Broadcom legacy switches which place the tag after the MAC source
++ address.
+
+ config NET_DSA_TAG_BRCM_PREPEND
+ tristate "Tag driver for Broadcom switches using prepended headers"
+--- a/net/dsa/tag_brcm.c
++++ b/net/dsa/tag_brcm.c
+@@ -11,9 +11,26 @@
+
+ #include "dsa_priv.h"
+
+-/* This tag length is 4 bytes, older ones were 6 bytes, we do not
+- * handle them
+- */
++/* Legacy Broadcom tag (6 bytes) */
++#define BRCM_LEG_TAG_LEN 6
++
++/* Type fields */
++/* 1st byte in the tag */
++#define BRCM_LEG_TYPE_HI 0x88
++/* 2nd byte in the tag */
++#define BRCM_LEG_TYPE_LO 0x74
++
++/* Tag fields */
++/* 3rd byte in the tag */
++#define BRCM_LEG_UNICAST (0 << 5)
++#define BRCM_LEG_MULTICAST (1 << 5)
++#define BRCM_LEG_EGRESS (2 << 5)
++#define BRCM_LEG_INGRESS (3 << 5)
++
++/* 6th byte in the tag */
++#define BRCM_LEG_PORT_ID (0xf)
++
++/* Newer Broadcom tag (4 bytes) */
+ #define BRCM_TAG_LEN 4
+
+ /* Tag is constructed and desconstructed using byte by byte access
+@@ -194,6 +211,87 @@ DSA_TAG_DRIVER(brcm_netdev_ops);
+ MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM);
+ #endif
+
++#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
++static struct sk_buff *brcm_leg_tag_xmit(struct sk_buff *skb,
++ struct net_device *dev)
++{
++ struct dsa_port *dp = dsa_slave_to_port(dev);
++ u8 *brcm_tag;
++
++ /* The Ethernet switch we are interfaced with needs packets to be at
++ * least 64 bytes (including FCS) otherwise they will be discarded when
++ * they enter the switch port logic. When Broadcom tags are enabled, we
++ * need to make sure that packets are at least 70 bytes
++ * (including FCS and tag) because the length verification is done after
++ * the Broadcom tag is stripped off the ingress packet.
++ *
++ * Let dsa_slave_xmit() free the SKB
++ */
++ if (__skb_put_padto(skb, ETH_ZLEN + BRCM_LEG_TAG_LEN, false))
++ return NULL;
++
++ skb_push(skb, BRCM_LEG_TAG_LEN);
++
++ memmove(skb->data, skb->data + BRCM_LEG_TAG_LEN, 2 * ETH_ALEN);
++
++ brcm_tag = skb->data + 2 * ETH_ALEN;
++
++ /* Broadcom tag type */
++ brcm_tag[0] = BRCM_LEG_TYPE_HI;
++ brcm_tag[1] = BRCM_LEG_TYPE_LO;
++
++ /* Broadcom tag value */
++ brcm_tag[2] = BRCM_LEG_EGRESS;
++ brcm_tag[3] = 0;
++ brcm_tag[4] = 0;
++ brcm_tag[5] = dp->index & BRCM_LEG_PORT_ID;
++
++ return skb;
++}
++
++static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
++ struct net_device *dev,
++ struct packet_type *pt)
++{
++ int source_port;
++ u8 *brcm_tag;
++
++ if (unlikely(!pskb_may_pull(skb, BRCM_LEG_PORT_ID)))
++ return NULL;
++
++ brcm_tag = skb->data - 2;
++
++ source_port = brcm_tag[5] & BRCM_LEG_PORT_ID;
++
++ 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_LEG_TAG_LEN);
++
++ skb->offload_fwd_mark = 1;
++
++ /* Move the Ethernet DA and SA */
++ memmove(skb->data - ETH_HLEN,
++ skb->data - ETH_HLEN - BRCM_LEG_TAG_LEN,
++ 2 * ETH_ALEN);
++
++ return skb;
++}
++
++static const struct dsa_device_ops brcm_legacy_netdev_ops = {
++ .name = "brcm-legacy",
++ .proto = DSA_TAG_PROTO_BRCM_LEGACY,
++ .xmit = brcm_leg_tag_xmit,
++ .rcv = brcm_leg_tag_rcv,
++ .overhead = BRCM_LEG_TAG_LEN,
++};
++
++DSA_TAG_DRIVER(brcm_legacy_netdev_ops);
++MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_LEGACY);
++#endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY */
++
+ #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
+ static struct sk_buff *brcm_tag_xmit_prepend(struct sk_buff *skb,
+ struct net_device *dev)
+@@ -226,6 +324,9 @@ static struct dsa_tag_driver *dsa_tag_dr
+ #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM)
+ &DSA_TAG_DRIVER_NAME(brcm_netdev_ops),
+ #endif
++#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
++ &DSA_TAG_DRIVER_NAME(brcm_legacy_netdev_ops),
++#endif
+ #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
+ &DSA_TAG_DRIVER_NAME(brcm_prepend_netdev_ops),
+ #endif
projects / openwrt / openwrt.git / blobdiff