[PATCH net-next v2 3/3] net: dsa: b53: support legacy FCS tags
From: Álvaro Fernández Rojas <hidden>
Date: 2025-06-10 16:32:02
Also in:
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Subsystem:
broadcom b53/sf2 ethernet switch driver, networking drivers, networking [dsa], the rest · Maintainers:
Florian Fainelli, Jonas Gorski, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Vladimir Oltean, Linus Torvalds
Commit 46c5176c586c ("net: dsa: b53: support legacy tags") introduced
support for legacy tags, but it turns out that BCM5325 and BCM5365
switches require the original FCS value and length, so they have to be
treated differently.
Fixes: 46c5176c586c ("net: dsa: b53: support legacy tags")
Signed-off-by: Álvaro Fernández Rojas <redacted>
---
drivers/net/dsa/b53/Kconfig | 1 +
drivers/net/dsa/b53/b53_common.c | 7 +++++--
2 files changed, 6 insertions(+), 2 deletions(-)
v2: no changes
diff --git a/drivers/net/dsa/b53/Kconfig b/drivers/net/dsa/b53/Kconfig
index ebaa4a80d5444..915008e8eff53 100644
--- a/drivers/net/dsa/b53/Kconfig
+++ b/drivers/net/dsa/b53/Kconfig@@ -5,6 +5,7 @@ menuconfig B53 select NET_DSA_TAG_NONE select NET_DSA_TAG_BRCM select NET_DSA_TAG_BRCM_LEGACY + select NET_DSA_TAG_BRCM_LEGACY_FCS select NET_DSA_TAG_BRCM_PREPEND help This driver adds support for Broadcom managed switch chips. It supports
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index 862bdccb74397..222107223d109 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c@@ -2245,8 +2245,11 @@ enum dsa_tag_protocol b53_get_tag_protocol(struct dsa_switch *ds, int port, goto out; } - /* Older models require a different 6 byte tag */ - if (is5325(dev) || is5365(dev) || is63xx(dev)) { + /* Older models require different 6 byte tags */ + if (is5325(dev) || is5365(dev)) { + dev->tag_protocol = DSA_TAG_PROTO_BRCM_LEGACY_FCS; + goto out; + } else if (is63xx(dev)) { dev->tag_protocol = DSA_TAG_PROTO_BRCM_LEGACY; goto out; }
--
2.39.5