Re: [PATCH 4/6] dt-bindings: riscv: Add DT binding documentation for Renesas RZ/Five SoC and SMARC EVK

From: Krzysztof Kozlowski
Date: Wed Jul 27 2022 - 09:00:48 EST


On 27/07/2022 14:56, Biju Das wrote:
>>
>> Then it is not the same SoC! Same means same, identical. CPU
>> architecture is one of the major differences, which means it is not the
>> same.
>
> Family SoC(R9A07G043) is at top level. Then it has different SoCId for taking care of
> differences for SoC based on ARMV8 and RISC-V which has separate compatible like
> r9a07g043u11 and r9a07g043f01?

This does not answer the concern - it's not the same SoC. The most
generic compatible denotes the most common part. I would argue that
instruction set and architecture are the most important differences.
None of ARMv8 SoCs (SoCs, not CPU cores) have "arm,armv8" compatible and
you went even more - you combined two architectures in the most generic
compatibles.

>
>>
>>> Using same SoM and Carrier board?
>>
>> It's like saying PC with x86 and ARMv8 board are the same because they
>> both use same "PC chassis".
>
> What I meant is board based on Family SoC(R9A07G043) that is either based on ARMv8 or
> RISC-V cpu architecture.

I don't see this related to the topic at all. What board do you use,
does not matter. The board does not change the fact these SoCs have
entirely different architecture - ARMv8 and RISC-V.


Best regards,
Krzysztof