[PATCH net] net: dsa: b53: Turn off Broadcom tags for more switches

[PATCH net] net: dsa: b53: Turn off Broadcom tags for more switches

[Florian Fainelli]

Models such as BCM5395/97/98 and BCM53125/24/53115 and compatible require that
we turn on managed mode to actually act on Broadcom tags, otherwise they just
pass them through on ingress (host -> switch) and don't insert them in egress
(switch -> host). Turning on managed mode is simple, but requires us to
properly support ARL misses on multicast addresses which is a much more
involved set of changes not suitable for a bug fix for this release.

Reported-by: Jochen Friedrich <jochen@scram.de>
Fixes: 7edc58d614d4 ("net: dsa: b53: Turn on Broadcom tags")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/net/dsa/b53/b53_common.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index f5a8dd96fd75..4498ab897d94 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -1500,10 +1500,13 @@ static enum dsa_tag_protocol b53_get_tag_protocol(struct dsa_switch *ds,
 {
 	struct b53_device *dev = ds->priv;
 
-	/* Older models support a different tag format that we do not
-	 * support in net/dsa/tag_brcm.c yet.
+	/* Older models (5325, 5365) support a different tag format that we do
+	 * not support in net/dsa/tag_brcm.c yet. 539x and 531x5 require managed
+	 * mode to be turned on which means we need to specifically manage ARL
+	 * misses on multicast addresses (TBD).
 	 */
-	if (is5325(dev) || is5365(dev) || !b53_can_enable_brcm_tags(ds, port))
+	if (is5325(dev) || is5365(dev) || is539x(dev) || is531x5(dev) ||
+	    !b53_can_enable_brcm_tags(ds, port))
 		return DSA_TAG_PROTO_NONE;
 
 	/* Broadcom BCM58xx chips have a flow accelerator on Port 8
-- 
2.14.1

Re: [PATCH net] net: dsa: b53: Turn off Broadcom tags for more switches

[David Miller]

From: Florian Fainelli <f.fainelli@gmail.com>
Date: Wed,  3 Jan 2018 22:02:29 -0800

> Models such as BCM5395/97/98 and BCM53125/24/53115 and compatible require that
> we turn on managed mode to actually act on Broadcom tags, otherwise they just
> pass them through on ingress (host -> switch) and don't insert them in egress
> (switch -> host). Turning on managed mode is simple, but requires us to
> properly support ARL misses on multicast addresses which is a much more
> involved set of changes not suitable for a bug fix for this release.
> 
> Reported-by: Jochen Friedrich <jochen@scram.de>
> Fixes: 7edc58d614d4 ("net: dsa: b53: Turn on Broadcom tags")
> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

Applied.