There are 2 distinct code paths (listed below) in the source code which set up an injection header for Ocelot(-like) switches. Code path (2) lacks the QoS class and source port being set correctly. Especially the improper QoS classification is a problem for the "ocelot-8021q" alternative DSA tagging protocol, because we support tc-taprio and each packet needs to be scheduled precisely through its time slot. This includes PTP, which is normally assigned to a traffic class other than 0, but would be sent through TC 0 nonetheless.
The code paths are:
(1) ocelot_xmit_common() from net/dsa/tag_ocelot.c - called only by the standard "ocelot" DSA tagging protocol which uses NPI-based injection - sets up bit fields in the tag manually to account for a small difference (destination port offset) between Ocelot and Seville. Namely, ocelot_ifh_set_dest() is omitted out of ocelot_xmit_common(), because there's also seville_ifh_set_dest().
(2) ocelot_ifh_set_basic(), called by: - ocelot_fdma_prepare_skb() for FDMA transmission of the ocelot switchdev driver - ocelot_port_xmit() -> ocelot_port_inject_frame() for register-based transmission of the ocelot switchdev driver - felix_port_deferred_xmit() -> ocelot_port_inject_frame() for the DSA tagger ocelot-8021q when it must transmit PTP frames (also through register-based injection). sets the bit fields according to its own logic.
The problem is that (2) doesn't call ocelot_ifh_set_qos_class(). Copying that logic from ocelot_xmit_common() fixes that.
Unfortunately, although desirable, it is not easily possible to de-duplicate code paths (1) and (2), and make net/dsa/tag_ocelot.c directly call ocelot_ifh_set_basic()), because of the ocelot/seville difference. This is the "minimal" fix with some logic duplicated (but at least more consolidated).
Fixes: 0a6f17c6ae21 ("net: dsa: tag_ocelot_8021q: add support for PTP timestamping") Signed-off-by: Vladimir Oltean vladimir.oltean@nxp.com --- drivers/net/ethernet/mscc/ocelot.c | 10 +++++++++- drivers/net/ethernet/mscc/ocelot_fdma.c | 1 - 2 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c index 69a4e5a90475..9301716e21d5 100644 --- a/drivers/net/ethernet/mscc/ocelot.c +++ b/drivers/net/ethernet/mscc/ocelot.c @@ -1208,13 +1208,21 @@ void ocelot_ifh_set_basic(void *ifh, struct ocelot *ocelot, int port, u32 rew_op, struct sk_buff *skb) { struct ocelot_port *ocelot_port = ocelot->ports[port]; + struct net_device *dev = skb->dev; u64 vlan_tci, tag_type; + int qos_class;
ocelot_xmit_get_vlan_info(skb, ocelot_port->bridge, &vlan_tci, &tag_type);
+ qos_class = netdev_get_num_tc(dev) ? + netdev_get_prio_tc_map(dev, skb->priority) : skb->priority; + + memset(ifh, 0, OCELOT_TAG_LEN); ocelot_ifh_set_bypass(ifh, 1); + ocelot_ifh_set_src(ifh, BIT_ULL(ocelot->num_phys_ports)); ocelot_ifh_set_dest(ifh, BIT_ULL(port)); + ocelot_ifh_set_qos_class(ifh, qos_class); ocelot_ifh_set_tag_type(ifh, tag_type); ocelot_ifh_set_vlan_tci(ifh, vlan_tci); if (rew_op) @@ -1225,7 +1233,7 @@ EXPORT_SYMBOL(ocelot_ifh_set_basic); void ocelot_port_inject_frame(struct ocelot *ocelot, int port, int grp, u32 rew_op, struct sk_buff *skb) { - u32 ifh[OCELOT_TAG_LEN / 4] = {0}; + u32 ifh[OCELOT_TAG_LEN / 4]; unsigned int i, count, last;
ocelot_write_rix(ocelot, QS_INJ_CTRL_GAP_SIZE(1) | diff --git a/drivers/net/ethernet/mscc/ocelot_fdma.c b/drivers/net/ethernet/mscc/ocelot_fdma.c index 87b59cc5e441..00326ae8c708 100644 --- a/drivers/net/ethernet/mscc/ocelot_fdma.c +++ b/drivers/net/ethernet/mscc/ocelot_fdma.c @@ -665,7 +665,6 @@ static int ocelot_fdma_prepare_skb(struct ocelot *ocelot, int port, u32 rew_op,
ifh = skb_push(skb, OCELOT_TAG_LEN); skb_put(skb, ETH_FCS_LEN); - memset(ifh, 0, OCELOT_TAG_LEN); ocelot_ifh_set_basic(ifh, ocelot, port, rew_op, skb);
return 0;