net: dsa: mv88e6xxx: fix 6351 family statistics snapshot

The 88E6171, 88E6175, 88E6350 and 88E6351 take the port number in the
low bits of the statistics operation register. The 6320 snapshot helper
instead encodes the port as (port + 1) << 5. On an EA4500 with an
88E6171, this causes ethtool -S to return physical port 0's MIB counters
for every user port. Traffic on other ports does not update their
reported hardware counters.

Before the snapshot operation was moved into the chip operations, only
the 6320 and 6352 families used the shifted encoding. The refactoring
incorrectly assigned that encoding to all four 6351 family chips.

Use the unshifted snapshot helper for the entire 6351 family. This
matches the Marvell DSDT statsCapture() implementation, which uses the
raw port number for chips outside DEV_RMON_PORT_BITS, including these
four chips.

The original 88E6171 change was tested on an EA4500: pings through
different switch ports updated only the corresponding port's hardware
counters. The other three chips have not been hardware tested.

Fixes: a605a0fe7115 ("net: dsa: mv88e6xxx: Abstract stats_snapshot into ops structure")
Link: https://lore.kernel.org/all/404d5f2d-24a5-4edc-897b-b1b3c54a20e1@lunn.ch/
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20261026164733.737299-2-f.fainelli@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

0 files changed, 0 insertions, 0 deletions