[PATCH net-next v11 1/7] dt-bindings: phy: document the serdes PHY on sa8255p

[Bartosz Golaszewski]

On Thu, 2 Jul 2026 11:16:22 +0200, Geert Uytterhoeven
<geert at linux-m68k.org> said:
> Hi Bartosz,
>
> On Thu, 2 Jul 2026 at 11:12, Bartosz Golaszewski <brgl at kernel.org> wrote:
>> On Tue, 30 Jun 2026 12:23:16 +0200, Vinod Koul <vkoul at kernel.org> said:
>> > On 29-06-26, 16:51, Geert Uytterhoeven wrote:
>> >> > Russell King asked me to put the PHY logic for SCMI pm domains into the PHY
>> >> > driver instead of the MAC driver where it was previously. Instead of cramming
>> >> > both HLOS and firmware handling into the same driver, I figured it makes more
>> >> > sense to have a dedicated, cleaner driver as the two share very little code (if
>> >> > any).
>> >>
>> >> I think you are mixing up DT bindings and driver implementation?
>> >
>> > Should the bindings change if we have different driver and firmware
>> > implementations? Isn't binding supposed to be agnostic of
>> > implementations..?
>>
>> I've thought about it some more and I believe this question is philosophical in
>> nature.
>>
>> sa8775p and sa8255p are *the same* hardware. I can flash different firmware on
>> the same Lemans Ride board and it becomes one or the other. Yet they are not
>> described by the same DTS and the bindings differ as well. I don't see why we
>> wouldn't allow the same approach for the this PHY.
>>
>> We treat it as different HW variant when it's managed by firmware - just like
>> we do with the rest of the SoC.
>
> DT describes hardware, not software policy.
>

I'll defer to DT maintainers then for that particular case because it affects
more than just this platform. For instance: Qualcomm Nord[1] is already being
upstreamed with a similar split into common parts and then sources specific to
the SCMI and non-SCMI variants - even though it's the same SoC.

Bartosz

[1] https://lore.kernel.org/all/20260526051300.1669201-1-shengchao.guo@oss.qualcomm.com/