Re: [PATCH 4/4] arm64: dts: qcom: sa8775p-ride: Add QCS9100 compatible

[Krzysztof Kozlowski <krzk@kernel.org>]

On 13/08/2024 10:59, Aiqun Yu (Maria) wrote:
>>>>>> Does "new board" mean that "old board" disappears? No users to care
>>>>>> about it? Or just the existing board is being changed (like new revision)?
>>>>>
>>>>> We will support both boards. Sa8775p-ride board with sa8775p chipset and
>>>>> sa8775p-ride board with qcs9100 chipset. Both of them can be used for
>>>>> development.
>>>>
>>>> Patch does something else then - changes compatibles for the existing
>>>> (old) board.
>>>
>>> Can you educate us the right way to add the qcs9100 SoC support in 
>>> sa8775p-ride board? We don't want to duplicate whole device tree file 
>>> since all the hardwares are same except the SoC, so we add qcs9100 SoC 
>>> compatible to sa8775p-ride board and still keep sa8775p SoC compatible.
>>
>> Split board DTS into shared DTSI (just don't forget about proper
>> -M/-C/-B arguments for format-patch) and include it in relevant boards.
>> You also need new SoC DTSI. This will be unusual code, but it matches
>> what you want to achieve.
> 
> If we create two additional DTSs, a total of four DTBs will be generated.
> Should we update the current board DTSs (sa8775p-ride-r3.dts and
> sa8775p-ride.dts) to support the pin-to-pin compatible QCS9100 and
> SA8775p SoCs?

I don't know, I don't have such device. Decision should be based on real
life, real events happening, real products, not on feelings.

> 
> Considering the higher usage of QCS9100 boards in IoT compared to
> SA8775p in automotive for these DTBs, perhaps we should prioritize the
> 'qcom,qcs9100' compatibility before 'qcom,sa8775p'.

Prioritize in what way? What does it mean?

Best regards,
Krzysztof