diff mbox series

[net,1/2] net: dsa: sja1105: always enable the INCL_SRCPT option

Message ID 20230626155112.3155993-2-vladimir.oltean@nxp.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series Fix PTP received on wrong port with bridged SJA1105 DSA | expand

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Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/cc_maintainers success CCed 8 of 8 maintainers
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 24 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Vladimir Oltean June 26, 2023, 3:51 p.m. UTC
Link-local traffic on bridged SJA1105 ports is sometimes tagged by the
hardware with source port information (when the port is under a VLAN
aware bridge).

The tag_8021q source port identification has become more loose
("imprecise") and will report a plausible rather than exact bridge port,
when under a bridge (be it VLAN-aware or VLAN-unaware). But link-local
traffic always needs to know the precise source port.

Modify the driver logic (and therefore: the tagging protocol itself) to
always include the source port information with link-local packets,
regardless of whether the port is standalone, under a VLAN-aware or
VLAN-unaware bridge. This makes it possible for the tagging driver to
give priority to that information over the tag_8021q VLAN header.

The big drawback with INCL_SRCPT is that it makes it impossible to
distinguish between an original MAC DA of 01:80:C2:XX:YY:ZZ and
01:80:C2:AA:BB:ZZ, because the tagger just patches MAC DA bytes 3 and 4
with zeroes. Only if PTP RX timestamping is enabled, the switch will
generate a META follow-up frame containing the RX timestamp and the
original bytes 3 and 4 of the MAC DA. Those will be used to patch up the
original packet. Nonetheless, in the absence of PTP RX timestamping, we
have to live with this limitation, since it is more important to have
the more precise source port information for link-local traffic.

Fixes: d7f9787a763f ("net: dsa: tag_8021q: add support for imprecise RX based on the VBID")
Fixes: 91495f21fcec ("net: dsa: tag_8021q: replace the SVL bridging with VLAN-unaware IVL bridging")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 drivers/net/dsa/sja1105/sja1105_main.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c
index a55a6436fc05..dd154b2b9680 100644
--- a/drivers/net/dsa/sja1105/sja1105_main.c
+++ b/drivers/net/dsa/sja1105/sja1105_main.c
@@ -866,11 +866,11 @@  static int sja1105_init_general_params(struct sja1105_private *priv)
 		.hostprio = 7,
 		.mac_fltres1 = SJA1105_LINKLOCAL_FILTER_A,
 		.mac_flt1    = SJA1105_LINKLOCAL_FILTER_A_MASK,
-		.incl_srcpt1 = false,
+		.incl_srcpt1 = true,
 		.send_meta1  = false,
 		.mac_fltres0 = SJA1105_LINKLOCAL_FILTER_B,
 		.mac_flt0    = SJA1105_LINKLOCAL_FILTER_B_MASK,
-		.incl_srcpt0 = false,
+		.incl_srcpt0 = true,
 		.send_meta0  = false,
 		/* Default to an invalid value */
 		.mirr_port = priv->ds->num_ports,
@@ -2405,11 +2405,6 @@  int sja1105_vlan_filtering(struct dsa_switch *ds, int port, bool enabled,
 	general_params->tpid = tpid;
 	/* EtherType used to identify outer tagged (S-tag) VLAN traffic */
 	general_params->tpid2 = tpid2;
-	/* When VLAN filtering is on, we need to at least be able to
-	 * decode management traffic through the "backup plan".
-	 */
-	general_params->incl_srcpt1 = enabled;
-	general_params->incl_srcpt0 = enabled;
 
 	for (port = 0; port < ds->num_ports; port++) {
 		if (dsa_is_unused_port(ds, port))