twx-linux/include/soc/mscc
Vladimir Oltean e83b49ecb5 net: mscc: ocelot: serialize access to the injection/extraction groups
[ 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 <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-29 17:33:45 +02:00
..
ocelot_ana.h net: dsa: felix: support psfp filter on vsc9959 2021-11-18 12:07:24 +00:00
ocelot_dev.h net: mscc: ocelot: add MAC Merge layer support for VSC9959 2023-01-23 12:44:18 +00:00
ocelot_hsio.h
ocelot_ptp.h net: mscc: ocelot: avoid overflowing the PTP timestamp FIFO 2021-10-12 17:35:17 -07:00
ocelot_qsys.h net: mscc: ocelot: add ops for decoding watermark threshold and occupancy 2021-01-15 20:02:34 -08:00
ocelot_sys.h net: mscc: ocelot: convert SYS_PAUSE_CFG register access to regfield 2020-07-13 17:40:02 -07:00
ocelot_vcap.h net: dsa: felix: tag_8021q preparation for multiple CPU ports 2022-05-23 10:39:55 +01:00
ocelot.h net: mscc: ocelot: serialize access to the injection/extraction groups 2024-08-29 17:33:45 +02:00
vsc7514_regs.h net: mscc: ocelot: un-export unused regmap symbols 2023-02-06 22:33:15 -08:00