Re: [PATCH net v3 1/3] net: dsa: mv88e6xxx: write the ATU FID register on 88E6141/88E6341

[Andrew Lunn]

On Wed, Jul 15, 2026 at 09:29:41AM +1000, Luke Howard wrote:
> The driver decided whether a device has a dedicated ATU FID register
> from its database count, taking the register path only when there were
> more than 256 databases. The 88E6141/88E6341 have 256 databases but do
> have the register, so they fell back to the legacy path and the FID
> register was never written. Every FDB entry was then loaded into FID 0,
> breaking VLAN aware bridging.
> 
> The number of databases does not imply whether the register is present.
> Add an explicit atu_fid_reg flag, set it on every device that has the
> register (all that previously matched the >256 heuristic, plus the
> 88E6141/88E6341), and key the register access off the flag instead of
> the database count.
> 
> Fixes: a75961d0ebfd ("net: dsa: mv88e6xxx: Add support for ethernet switch 88E6341")
> Assisted-by: Claude:claude-opus-4-8
> Signed-off-by: Luke Howard <lukeh@xxxxxxxx>

Reviewed-by: Andrew Lunn <andrew@xxxxxxx>

    Andrew