mirrors/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-12-27 11:06:41 -05:00
Code Issues Packages Projects Releases Wiki Activity

net: dsa: tag_brcm: add support for legacy FCS tags

Browse Source 
Add support for legacy Broadcom FCS tags, which are similar to
DSA_TAG_PROTO_BRCM_LEGACY.
BCM5325 and BCM5365 switches require including the original FCS value and
length, as opposed to BCM63xx switches.
Adding the original FCS value and length to DSA_TAG_PROTO_BRCM_LEGACY would
impact performance of BCM63xx switches, so it's better to create a new tag.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://patch.msgid.link/20250614080000.1884236-3-noltari@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Álvaro Fernández Rojas
2025-06-14 09:59:48 +02:00
committed by Jakub Kicinski
parent a4daaf063f
commit ef07df397a
3 changed files with 88 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
include/net/dsa.h
View File

@@ -54,11 +54,13 @@ struct tc_action;
#define DSA_TAG_PROTO_RZN1_A5PSW_VALUE 26
#define DSA_TAG_PROTO_LAN937X_VALUE 27
#define DSA_TAG_PROTO_VSC73XX_8021Q_VALUE 28
#define DSA_TAG_PROTO_BRCM_LEGACY_FCS_VALUE 29
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_LEGACY_FCS = DSA_TAG_PROTO_BRCM_LEGACY_FCS_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,

16
net/dsa/Kconfig
View File

@@ -42,12 +42,24 @@ config NET_DSA_TAG_BRCM
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"
tristate "Tag driver for BCM63xx 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
BCM63xx legacy switches which place the tag after the MAC source
address.
This tag is used in BCM63xx legacy switches which work without the
original FCS and length before the tag insertion.
config NET_DSA_TAG_BRCM_LEGACY_FCS
tristate "Tag driver for BCM53xx 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
BCM53xx legacy switches which place the tag after the MAC source
address.
This tag is used in BCM53xx legacy switches which expect original
FCS and length before the tag insertion to be present.
config NET_DSA_TAG_BRCM_PREPEND
tristate "Tag driver for Broadcom switches using prepended headers"

73
net/dsa/tag_brcm.c
View File

@@ -15,6 +15,7 @@
#define BRCM_NAME "brcm"
#define BRCM_LEGACY_NAME "brcm-legacy"
#define BRCM_LEGACY_FCS_NAME "brcm-legacy-fcs"
#define BRCM_PREPEND_NAME "brcm-prepend"
/* Legacy Broadcom tag (6 bytes) */
@@ -32,6 +33,10 @@
#define BRCM_LEG_MULTICAST (1 << 5)
#define BRCM_LEG_EGRESS (2 << 5)
#define BRCM_LEG_INGRESS (3 << 5)
#define BRCM_LEG_LEN_HI(x) (((x) >> 8) & 0x7)
/* 4th byte in the tag */
#define BRCM_LEG_LEN_LO(x) ((x) & 0xff)
/* 6th byte in the tag */
#define BRCM_LEG_PORT_ID (0xf)
@@ -212,7 +217,8 @@ DSA_TAG_DRIVER(brcm_netdev_ops);
MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM, BRCM_NAME);
#endif
#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY) || \
IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY_FCS)
static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
struct net_device *dev)
{
@@ -244,7 +250,9 @@ static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
return skb;
}
#endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY || CONFIG_NET_DSA_TAG_BRCM_LEGACY_FCS */
#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)
{
@@ -294,6 +302,66 @@ DSA_TAG_DRIVER(brcm_legacy_netdev_ops);
MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_LEGACY, BRCM_LEGACY_NAME);
#endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY */
#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY_FCS)
static struct sk_buff *brcm_leg_fcs_tag_xmit(struct sk_buff *skb,
struct net_device *dev)
{
struct dsa_port *dp = dsa_user_to_port(dev);
unsigned int fcs_len;
__le32 fcs_val;
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_user_xmit() free the SKB.
*/
if (__skb_put_padto(skb, ETH_ZLEN + BRCM_LEG_TAG_LEN, false))
return NULL;
fcs_len = skb->len;
fcs_val = cpu_to_le32(crc32_le(~0, skb->data, fcs_len) ^ ~0);
skb_push(skb, BRCM_LEG_TAG_LEN);
dsa_alloc_etype_header(skb, BRCM_LEG_TAG_LEN);
brcm_tag = skb->data + 2 * ETH_ALEN;
/* Broadcom tag type */
brcm_tag[0] = BRCM_LEG_TYPE_HI;
brcm_tag[1] = BRCM_LEG_TYPE_LO;
/* Broadcom tag value */
brcm_tag[2] = BRCM_LEG_EGRESS | BRCM_LEG_LEN_HI(fcs_len);
brcm_tag[3] = BRCM_LEG_LEN_LO(fcs_len);
brcm_tag[4] = 0;
brcm_tag[5] = dp->index & BRCM_LEG_PORT_ID;
/* Original FCS value */
if (__skb_pad(skb, ETH_FCS_LEN, false))
return NULL;
skb_put_data(skb, &fcs_val, ETH_FCS_LEN);
return skb;
}
static const struct dsa_device_ops brcm_legacy_fcs_netdev_ops = {
.name = BRCM_LEGACY_FCS_NAME,
.proto = DSA_TAG_PROTO_BRCM_LEGACY_FCS,
.xmit = brcm_leg_fcs_tag_xmit,
.rcv = brcm_leg_tag_rcv,
.needed_headroom = BRCM_LEG_TAG_LEN,
};
DSA_TAG_DRIVER(brcm_legacy_fcs_netdev_ops);
MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_LEGACY_FCS, BRCM_LEGACY_FCS_NAME);
#endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY_FCS */
#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)
@@ -328,6 +396,9 @@ static struct dsa_tag_driver *dsa_tag_driver_array[] = {
#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_LEGACY_FCS)
&DSA_TAG_DRIVER_NAME(brcm_legacy_fcs_netdev_ops),
#endif
#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
&DSA_TAG_DRIVER_NAME(brcm_prepend_netdev_ops),
#endif