kernel/linux.git/include/soc/mscc, branch v6.6.132

net: mscc: ocelot: treat 802.1ad tagged traffic as 802.1Q-untagged

2025-05-09T07:43:58+00:00

[ Upstream commit 36dd1141be70b5966906919714dc504a24c65ddf ] I was revisiting the topic of 802.1ad treatment in the Ocelot switch [0] and realized that not only is its basic VLAN classification pipeline improper for offloading vlan_protocol 802.1ad bridges, but also improper for offloading regular 802.1Q bridges already. Namely, 802.1ad-tagged traffic should be treated as VLAN-untagged by bridged ports, but this switch treats it as if it was 802.1Q-tagged with the same VID as in the 802.1ad header. This is markedly different to what the Linux bridge expects; see the "other_tpid()" function in tools/testing/selftests/net/forwarding/bridge_vlan_aware.sh. An idea came to me that the VCAP IS1 TCAM is more powerful than I'm giving it credit for, and that it actually overwrites the classified VID before the VLAN Table lookup takes place. In other words, it can be used even to save a packet from being dropped on ingress due to VLAN membership. Add a sophisticated TCAM rule hardcoded into the driver to force the switch to behave like a Linux bridge with vlan_filtering 1 vlan_protocol 802.1Q. Regarding the lifetime of the filter: eventually the bridge will disappear, and vlan_filtering on the port will be restored to 0 for standalone mode. Then the filter will be deleted. [0]: https://lore.kernel.org/netdev/20201009122947.nvhye4hvcha3tljh@skbuf/ Fixes: 7142529f1688 ("net: mscc: ocelot: add VLAN filtering") Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller Stable-dep-of: 5ec6d7d737a4 ("net: mscc: ocelot: delete PVID VLAN when readding it as non-PVID") Signed-off-by: Sasha Levin

net: mscc: ocelot: be resilient to loss of PTP packets during transmission

2024-12-19T17:11:29+00:00

[ Upstream commit b454abfab52543c44b581afc807b9f97fc1e7a3a ] The Felix DSA driver presents unique challenges that make the simplistic ocelot PTP TX timestamping procedure unreliable: any transmitted packet may be lost in hardware before it ever leaves our local system. This may happen because there is congestion on the DSA conduit, the switch CPU port or even user port (Qdiscs like taprio may delay packets indefinitely by design). The technical problem is that the kernel, i.e. ocelot_port_add_txtstamp_skb(), runs out of timestamp IDs eventually, because it never detects that packets are lost, and keeps the IDs of the lost packets on hold indefinitely. The manifestation of the issue once the entire timestamp ID range becomes busy looks like this in dmesg: mscc_felix 0000:00:00.5: port 0 delivering skb without TX timestamp mscc_felix 0000:00:00.5: port 1 delivering skb without TX timestamp At the surface level, we need a timeout timer so that the kernel knows a timestamp ID is available again. But there is a deeper problem with the implementation, which is the monotonically increasing ocelot_port->ts_id. In the presence of packet loss, it will be impossible to detect that and reuse one of the holes created in the range of free timestamp IDs. What we actually need is a bitmap of 63 timestamp IDs tracking which one is available. That is able to use up holes caused by packet loss, but also gives us a unique opportunity to not implement an actual timer_list for the timeout timer (very complicated in terms of locking). We could only declare a timestamp ID stale on demand (lazily), aka when there's no other timestamp ID available. There are pros and cons to this approach: the implementation is much more simple than per-packet timers would be, but most of the stale packets would be quasi-leaked - not really leaked, but blocked in driver memory, since this algorithm sees no reason to free them. An improved technique would be to check for stale timestamp IDs every time we allocate a new one. Assuming a constant flux of PTP packets, this avoids stale packets being blocked in memory, but of course, packets lost at the end of the flux are still blocked until the flux resumes (nobody left to kick them out). Since implementing per-packet timers is way too complicated, this should be good enough. Testing procedure: Persistently block traffic class 5 and try to run PTP on it: $ tc qdisc replace dev swp3 parent root taprio num_tc 8 \ map 0 1 2 3 4 5 6 7 queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \ base-time 0 sched-entry S 0xdf 100000 flags 0x2 [ 126.948141] mscc_felix 0000:00:00.5: port 3 tc 5 min gate length 0 ns not enough for max frame size 1526 at 1000 Mbps, dropping frames over 1 octets including FCS $ ptp4l -i swp3 -2 -P -m --socket_priority 5 --fault_reset_interval ASAP --logSyncInterval -3 ptp4l[70.351]: port 1 (swp3): INITIALIZING to LISTENING on INIT_COMPLETE ptp4l[70.354]: port 0 (/var/run/ptp4l): INITIALIZING to LISTENING on INIT_COMPLETE ptp4l[70.358]: port 0 (/var/run/ptp4lro): INITIALIZING to LISTENING on INIT_COMPLETE [ 70.394583] mscc_felix 0000:00:00.5: port 3 timestamp id 0 ptp4l[70.406]: timed out while polling for tx timestamp ptp4l[70.406]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it ptp4l[70.406]: port 1 (swp3): send peer delay response failed ptp4l[70.407]: port 1 (swp3): clearing fault immediately ptp4l[70.952]: port 1 (swp3): new foreign master d858d7.fffe.00ca6d-1 [ 71.394858] mscc_felix 0000:00:00.5: port 3 timestamp id 1 ptp4l[71.400]: timed out while polling for tx timestamp ptp4l[71.400]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it ptp4l[71.401]: port 1 (swp3): send peer delay response failed ptp4l[71.401]: port 1 (swp3): clearing fault immediately [ 72.393616] mscc_felix 0000:00:00.5: port 3 timestamp id 2 ptp4l[72.401]: timed out while polling for tx timestamp ptp4l[72.402]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it ptp4l[72.402]: port 1 (swp3): send peer delay response failed ptp4l[72.402]: port 1 (swp3): clearing fault immediately ptp4l[72.952]: port 1 (swp3): new foreign master d858d7.fffe.00ca6d-1 [ 73.395291] mscc_felix 0000:00:00.5: port 3 timestamp id 3 ptp4l[73.400]: timed out while polling for tx timestamp ptp4l[73.400]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it ptp4l[73.400]: port 1 (swp3): send peer delay response failed ptp4l[73.400]: port 1 (swp3): clearing fault immediately [ 74.394282] mscc_felix 0000:00:00.5: port 3 timestamp id 4 ptp4l[74.400]: timed out while polling for tx timestamp ptp4l[74.401]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it ptp4l[74.401]: port 1 (swp3): send peer delay response failed ptp4l[74.401]: port 1 (swp3): clearing fault immediately ptp4l[74.953]: port 1 (swp3): new foreign master d858d7.fffe.00ca6d-1 [ 75.396830] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 0 which seems lost [ 75.405760] mscc_felix 0000:00:00.5: port 3 timestamp id 0 ptp4l[75.410]: timed out while polling for tx timestamp ptp4l[75.411]: increasing tx_timestamp_timeout or increasing kworker priority may correct this issue, but a driver bug likely causes it ptp4l[75.411]: port 1 (swp3): send peer delay response failed ptp4l[75.411]: port 1 (swp3): clearing fault immediately (...) Remove the blocking condition and see that the port recovers: $ same tc command as above, but use "sched-entry S 0xff" instead $ same ptp4l command as above ptp4l[99.489]: port 1 (swp3): INITIALIZING to LISTENING on INIT_COMPLETE ptp4l[99.490]: port 0 (/var/run/ptp4l): INITIALIZING to LISTENING on INIT_COMPLETE ptp4l[99.492]: port 0 (/var/run/ptp4lro): INITIALIZING to LISTENING on INIT_COMPLETE [ 100.403768] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 0 which seems lost [ 100.412545] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 1 which seems lost [ 100.421283] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 2 which seems lost [ 100.430015] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 3 which seems lost [ 100.438744] mscc_felix 0000:00:00.5: port 3 invalidating stale timestamp ID 4 which seems lost [ 100.447470] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 100.505919] mscc_felix 0000:00:00.5: port 3 timestamp id 0 ptp4l[100.963]: port 1 (swp3): new foreign master d858d7.fffe.00ca6d-1 [ 101.405077] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 101.507953] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 102.405405] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 102.509391] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 103.406003] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 103.510011] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 104.405601] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 104.510624] mscc_felix 0000:00:00.5: port 3 timestamp id 0 ptp4l[104.965]: selected best master clock d858d7.fffe.00ca6d ptp4l[104.966]: port 1 (swp3): assuming the grand master role ptp4l[104.967]: port 1 (swp3): LISTENING to GRAND_MASTER on RS_GRAND_MASTER [ 105.106201] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 105.232420] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 105.359001] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 105.405500] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 105.485356] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 105.511220] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 105.610938] mscc_felix 0000:00:00.5: port 3 timestamp id 0 [ 105.737237] mscc_felix 0000:00:00.5: port 3 timestamp id 0 (...) Notice that in this new usage pattern, a non-congested port should basically use timestamp ID 0 all the time, progressing to higher numbers only if there are unacknowledged timestamps in flight. Compare this to the old usage, where the timestamp ID used to monotonically increase modulo OCELOT_MAX_PTP_ID. In terms of implementation, this simplifies the bookkeeping of the ocelot_port :: ts_id and ptp_skbs_in_flight. Since we need to traverse the list of two-step timestampable skbs for each new packet anyway, the information can already be computed and does not need to be stored. Also, ocelot_port->tx_skbs is always accessed under the switch-wide ocelot->ts_id_lock IRQ-unsafe spinlock, so we don't need the skb queue's lock and can use the unlocked primitives safely. This problem was actually detected using the tc-taprio offload, and is causing trouble in TSN scenarios, which Felix (NXP LS1028A / VSC9959) supports but Ocelot (VSC7514) does not. Thus, I've selected the commit to blame as the one adding initial timestamping support for the Felix switch. Fixes: c0bcf537667c ("net: dsa: ocelot: add hardware timestamping support for Felix") Signed-off-by: Vladimir Oltean Link: https://patch.msgid.link/20241205145519.1236778-5-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: mscc: ocelot: serialize access to the injection/extraction groups

2024-08-29T15:33:45+00:00

[ Upstream commit c5e12ac3beb0dd3a718296b2d8af5528e9ab728e ] As explained by Horatiu Vultur in commit 603ead96582d ("net: sparx5: Add spinlock for frame transmission from CPU") which is for a similar hardware design, multiple CPUs can simultaneously perform injection or extraction. There are only 2 register groups for injection and 2 for extraction, and the driver only uses one of each. So we'd better serialize access using spin locks, otherwise frame corruption is possible. Note that unlike in sparx5, FDMA in ocelot does not have this issue because struct ocelot_fdma_tx_ring already contains an xmit_lock. I guess this is mostly a problem for NXP LS1028A, as that is dual core. I don't think VSC7514 is. So I'm blaming the commit where LS1028A (aka the felix DSA driver) started using register-based packet injection and extraction. Fixes: 0a6f17c6ae21 ("net: dsa: tag_ocelot_8021q: add support for PTP timestamping") Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: mscc: ocelot: use ocelot_xmit_get_vlan_info() also for FDMA and register injection

2024-08-29T15:33:45+00:00

[ Upstream commit 67c3ca2c5cfe6a50772514e3349b5e7b3b0fac03 ] Problem description ------------------- On an NXP LS1028A (felix DSA driver) with the following configuration: - ocelot-8021q tagging protocol - VLAN-aware bridge (with STP) spanning at least swp0 and swp1 - 8021q VLAN upper interfaces on swp0 and swp1: swp0.700, swp1.700 - ptp4l on swp0.700 and swp1.700 we see that the ptp4l instances do not see each other's traffic, and they all go to the grand master state due to the ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES condition. Jumping to the conclusion for the impatient ------------------------------------------- There is a zero-day bug in the ocelot switchdev driver in the way it handles VLAN-tagged packet injection. The correct logic already exists in the source code, in function ocelot_xmit_get_vlan_info() added by commit 5ca721c54d86 ("net: dsa: tag_ocelot: set the classified VLAN during xmit"). But it is used only for normal NPI-based injection with the DSA "ocelot" tagging protocol. The other injection code paths (register-based and FDMA-based) roll their own wrong logic. This affects and was noticed on the DSA "ocelot-8021q" protocol because it uses register-based injection. By moving ocelot_xmit_get_vlan_info() to a place that's common for both the DSA tagger and the ocelot switch library, it can also be called from ocelot_port_inject_frame() in ocelot.c. We need to touch the lines with ocelot_ifh_port_set()'s prototype anyway, so let's rename it to something clearer regarding what it does, and add a kernel-doc. ocelot_ifh_set_basic() should do. Investigation notes ------------------- Debugging reveals that PTP event (aka those carrying timestamps, like Sync) frames injected into swp0.700 (but also swp1.700) hit the wire with two VLAN tags: 00000000: 01 1b 19 00 00 00 00 01 02 03 04 05 81 00 02 bc ~~~~~~~~~~~ 00000010: 81 00 02 bc 88 f7 00 12 00 2c 00 00 02 00 00 00 ~~~~~~~~~~~ 00000020: 00 00 00 00 00 00 00 00 00 00 00 01 02 ff fe 03 00000030: 04 05 00 01 00 04 00 00 00 00 00 00 00 00 00 00 00000040: 00 00 The second (unexpected) VLAN tag makes felix_check_xtr_pkt() -> ptp_classify_raw() fail to see these as PTP packets at the link partner's receiving end, and return PTP_CLASS_NONE (because the BPF classifier is not written to expect 2 VLAN tags). The reason why packets have 2 VLAN tags is because the transmission code treats VLAN incorrectly. Neither ocelot switchdev, nor felix DSA, declare the NETIF_F_HW_VLAN_CTAG_TX feature. Therefore, at xmit time, all VLANs should be in the skb head, and none should be in the hwaccel area. This is done by: static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, netdev_features_t features) { if (skb_vlan_tag_present(skb) && !vlan_hw_offload_capable(features, skb->vlan_proto)) skb = __vlan_hwaccel_push_inside(skb); return skb; } But ocelot_port_inject_frame() handles things incorrectly: ocelot_ifh_port_set(ifh, port, rew_op, skb_vlan_tag_get(skb)); void ocelot_ifh_port_set(struct sk_buff *skb, void *ifh, int port, u32 rew_op) { (...) if (vlan_tag) ocelot_ifh_set_vlan_tci(ifh, vlan_tag); (...) } The way __vlan_hwaccel_push_inside() pushes the tag inside the skb head is by calling: static inline void __vlan_hwaccel_clear_tag(struct sk_buff *skb) { skb->vlan_present = 0; } which does _not_ zero out skb->vlan_tci as seen by skb_vlan_tag_get(). This means that ocelot, when it calls skb_vlan_tag_get(), sees (and uses) a residual skb->vlan_tci, while the same VLAN tag is _already_ in the skb head. The trivial fix for double VLAN headers is to replace the content of ocelot_ifh_port_set() with: if (skb_vlan_tag_present(skb)) ocelot_ifh_set_vlan_tci(ifh, skb_vlan_tag_get(skb)); but this would not be correct either, because, as mentioned, vlan_hw_offload_capable() is false for us, so we'd be inserting dead code and we'd always transmit packets with VID=0 in the injection frame header. I can't actually test the ocelot switchdev driver and rely exclusively on code inspection, but I don't think traffic from 8021q uppers has ever been injected properly, and not double-tagged. Thus I'm blaming the introduction of VLAN fields in the injection header - early driver code. As hinted at in the early conclusion, what we _want_ to happen for VLAN transmission was already described once in commit 5ca721c54d86 ("net: dsa: tag_ocelot: set the classified VLAN during xmit"). ocelot_xmit_get_vlan_info() intends to ensure that if the port through which we're transmitting is under a VLAN-aware bridge, the outer VLAN tag from the skb head is stripped from there and inserted into the injection frame header (so that the packet is processed in hardware through that actual VLAN). And in all other cases, the packet is sent with VID=0 in the injection frame header, since the port is VLAN-unaware and has logic to strip this VID on egress (making it invisible to the wire). Fixes: 08d02364b12f ("net: mscc: fix the injection header") Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: mscc: ocelot: Remove unused declarations

2023-08-22T17:29:15+00:00

Commit 6c30384eb1de ("net: mscc: ocelot: register devlink ports") declared but never implemented ocelot_devlink_init() and ocelot_devlink_teardown(). Commit 2096805497e2 ("net: mscc: ocelot: automatically detect VCAP constants") declared but never implemented ocelot_detect_vcap_constants(). Commit 403ffc2c34de ("net: mscc: ocelot: add support for preemptible traffic classes") declared but never implemented ocelot_port_update_preemptible_tcs(). Signed-off-by: Yue Haibing Reviewed-by: Vladimir Oltean Link: https://lore.kernel.org/r/20230821130218.19096-1-yuehaibing@huawei.com Signed-off-by: Jakub Kicinski

net: dsa: felix: make vsc9959_tas_guard_bands_update() visible to ocelot->ops

2023-07-07T02:10:22+00:00

In a future change we will need to make ocelot_port_update_active_preemptible_tcs() call vsc9959_tas_guard_bands_update(), but that is currently not possible, since the ocelot switch lib does not have access to functions private to the DSA wrapper. Move the pointer to vsc9959_tas_guard_bands_update() from felix->info (which is private to the DSA driver) to ocelot->ops (which is also visible to the ocelot switch lib). Signed-off-by: Vladimir Oltean Message-ID: <20230705104422.49025-3-vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski

net: mscc: ocelot: extend ocelot->fwd_domain_lock to cover ocelot->tas_lock

2023-07-07T02:10:22+00:00

In a future commit we will have to call vsc9959_tas_guard_bands_update() from ocelot_port_update_active_preemptible_tcs(), and that will be impossible due to the AB/BA locking dependencies between ocelot->tas_lock and ocelot->fwd_domain_lock. Just like we did in commit 3ff468ef987e ("net: mscc: ocelot: remove struct ocelot_mm_state :: lock"), the only solution is to expand the scope of ocelot->fwd_domain_lock for it to also serialize changes made to the Time-Aware Shaper, because those will have to result in a recalculation of cut-through TCs, which is something that depends on the forwarding domain. Signed-off-by: Vladimir Oltean Message-ID: <20230705104422.49025-2-vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski

net: mscc: ocelot: don't keep PTP configuration of all ports in single structure

2023-06-29T10:40:27+00:00

In a future change, the driver will need to determine whether PTP RX timestamping is enabled on a port (including whether traps were set up on that port in particular) and that is currently not possible. The driver supports different RX filters (L2, L4) and kinds of TX timestamping (one-step, two-step) on its ports, but it saves all configuration in a single struct hwtstamp_config that is global to the switch. So, the latest timestamping configuration on one port (including a request to disable timestamping) affects what gets reported for all ports, even though the configuration itself is still individual to each port. The port timestamping configurations are only coupled because of the common structure, so replace the hwtstamp_config with a mask of trapped protocols saved per port. We also have the ptp_cmd to distinguish between one-step and two-step PTP timestamping, so with those 2 bits of information we can fully reconstruct a descriptive struct hwtstamp_config for each port, during the SIOCGHWTSTAMP ioctl. Fixes: 4e3b0468e6d7 ("net: mscc: PTP Hardware Clock (PHC) support") Fixes: 96ca08c05838 ("net: mscc: ocelot: set up traps for PTP packets") Signed-off-by: Vladimir Oltean Signed-off-by: Paolo Abeni

net: mscc: ocelot: add support for preemptible traffic classes

2023-04-18T02:01:19+00:00

In order to not transmit (preemptible) frames which will be received by the link partner as corrupted (because it doesn't support FP), the hardware requires the driver to program the QSYS_PREEMPTION_CFG_P_QUEUES register only after the MAC Merge layer becomes active (verification succeeds, or was disabled). There are some cases when FP is known (through experimentation) to be broken. Give priority to FP over cut-through switching, and disable FP for known broken link modes. Signed-off-by: Vladimir Oltean Reviewed-by: Simon Horman Signed-off-by: Jakub Kicinski

net: mscc: ocelot: add support for mqprio offload

2023-04-18T02:01:19+00:00

This doesn't apply anything to hardware and in general doesn't do anything that the software variant doesn't do, except for checking that there isn't more than 1 TXQ per TC (TXQs for a DSA switch are a dubious concept anyway). The reason we add this is to be able to parse one more field added to struct tc_mqprio_qopt_offload, namely preemptible_tcs. Signed-off-by: Vladimir Oltean Reviewed-by: Ferenc Fejes Reviewed-by: Simon Horman Reviewed-by: Florian Fainelli Signed-off-by: Jakub Kicinski