Re: [PATCH net-next v6 1/9] net: dsa: microchip: Add support for KSZ8463 global irq

[Vladimir Oltean]

On Wed, Mar 11, 2026 at 01:53:38PM +0100, Bastien Curutchet wrote:
> On 3/11/26 12:53 PM, Vladimir Oltean wrote:
> > On Wed, Mar 11, 2026 at 11:02:35AM +0100, Bastien Curutchet wrote:
> > > I, more or less, managed to fit this PTP support in the current framework,
> > > but the next series I prepared to add periodic output support is full of
> > > is_ksz8463() branches. So I think that I'll go with what you suggested and
> > > try to move the KSZ8463 support in the ksz8995.c driver. It will probably be
> > > cleaner this way.
> > > 
> > > TBH I'm a bit lost with all these KSZ variants but IIUC KSZ8463 and KSZ8995
> > > both belong to the 'old generation' of the hardware. Maybe a good split
> > > would be to have these old switches in the ksz8995.c driver and keep the
> > > rest under ksz_common infra.
> > 
> > Wait, to make sure I understand, you said you're going to rebase this
> > series onto the ksz8995 driver?
> 
> Well I'll first add basic support for the KSZ8463 in the ksz8995 driver and
> then add interrupt and PTP support on top of it yes. Did I misunderstand
> you're suggestion ?

If we're splitting drivers, I would like to see them grouped by actual similarity,
so as to not repeat the same mistakes.

I took a random feature, user port separation, and I'm comparing how Linus
implemented it in ksz8995:
https://lore.kernel.org/netdev/20260219-ks8995-fixups-v3-5-a7fc63fe1916@xxxxxxxxxx/
vs the register map from KSZ8463:
https://www.microchip.com/en-us/product/ksz8463#Documentation

Apart from some funky naming differences (KS8995_REG_PC1 corresponds to
"PORT 1 CONTROL REGISTER 2"), it should be pretty similar, right? Do you
see some differences requiring major surgery in ks8995?

Apart from the obvious incompleteness, of course. That driver currently
reports DSA_TAG_PROTO_NONE. It will have to return DSA_TAG_PROTO_KS8995
for ks8995:
https://lore.kernel.org/netdev/20260107-ks8995-dsa-tagging-v1-1-1a92832c1540@xxxxxxxxxx/
and DSA_TAG_PROTO_KSZ9893 for your KSZ8463. Right?