Commit 07bcf685 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'b53-legacy-tags'



Álvaro Fernández Rojas says:

====================
net: dsa: b53: support legacy tags

Legacy Broadcom tags are needed for older switches.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 73a2218c 46c5176c
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+1 −0
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ menuconfig B53
	tristate "Broadcom BCM53xx managed switch support"
	depends on NET_DSA
	select NET_DSA_TAG_BRCM
	select NET_DSA_TAG_BRCM_LEGACY
	select NET_DSA_TAG_BRCM_PREPEND
	help
	  This driver adds support for Broadcom managed switch chips. It supports
+7 −5
Original line number Diff line number Diff line
@@ -2055,15 +2055,17 @@ enum dsa_tag_protocol b53_get_tag_protocol(struct dsa_switch *ds, int port,
{
	struct b53_device *dev = ds->priv;

	/* Older models (5325, 5365) support a different tag format that we do
	 * not support in net/dsa/tag_brcm.c yet.
	 */
	if (is5325(dev) || is5365(dev) ||
	    !b53_can_enable_brcm_tags(ds, port, mprot)) {
	if (!b53_can_enable_brcm_tags(ds, port, mprot)) {
		dev->tag_protocol = DSA_TAG_PROTO_NONE;
		goto out;
	}

	/* Older models require a different 6 byte tag */
	if (is5325(dev) || is5365(dev) || is63xx(dev)) {
		dev->tag_protocol = DSA_TAG_PROTO_BRCM_LEGACY;
		goto out;
	}

	/* Broadcom BCM58xx chips have a flow accelerator on Port 8
	 * which requires us to use the prepended Broadcom tag type
	 */
+2 −0
Original line number Diff line number Diff line
@@ -49,10 +49,12 @@ struct phylink_link_state;
#define DSA_TAG_PROTO_XRS700X_VALUE		19
#define DSA_TAG_PROTO_OCELOT_8021Q_VALUE	20
#define DSA_TAG_PROTO_SEVILLE_VALUE		21
#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,
+7 −0
Original line number Diff line number Diff line
@@ -48,6 +48,13 @@ 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"
+104 −3
Original line number Diff line number Diff line
@@ -12,9 +12,26 @@

#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
@@ -195,6 +212,87 @@ 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)
@@ -227,6 +325,9 @@ static struct dsa_tag_driver *dsa_tag_driver_array[] = {
#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM)
	&DSA_TAG_DRIVER_NAME(brcm_netdev_ops),
#endif
#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
	&DSA_TAG_DRIVER_NAME(brcm_legacy_netdev_ops),
#endif
#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
	&DSA_TAG_DRIVER_NAME(brcm_prepend_netdev_ops),
#endif