Re: [PATCH 3/5] watchdog: Make RZV2HWDT driver depend on ARCH_R9A09G47

[Krzysztof Kozlowski <krzk@kernel.org>]

On 24/01/2025 11:57, Biju Das wrote:
> Hi Krzysztof Kozlowski,
> 
>> -----Original Message-----
>> From: Krzysztof Kozlowski <krzk@kernel.org>
>> Sent: 24 January 2025 10:35
>> Subject: Re: [PATCH 3/5] watchdog: Make RZV2HWDT driver depend on ARCH_R9A09G47
>>
>> On 24/01/2025 11:20, Biju Das wrote:
>>>>
>>>>> +	depends on ARCH_R9A09G047 || ARCH_R9A09G057 || COMPILE_TEST
>>>>
>>>> But this is just wrong. You are supposed to depend on renesas ARHC,
>>>> not your individual SoC (and this is what you called here "ARCH_R9A...").
>>>>
>>>> Greg many times gave strong opinion that even full ARCH is wrong and
>>>> we managed to convince him that it has a meaning (or he did not want
>>>> to keep discussing). But restricting it per soc is pointless and impossible to defend in
>> discussion.
>>>
>>> Currently for building RZ/G3E WDT, I need to always have RZ/V2H SoC config.
>>> which is pointless. May be ARCH_RENESAS should ok in this case??
>> Assuming ARCH_RENESAS covers your individual SoCs above, yes, that's the way for driver to limit
>> themselves to usable family.
> 
> ARCH_RENESAS has ARM, ARM64 and RISC based SoCs.
> 
> Currently it covers ARCH_RCAR_GEN1, ARCH_RCAR_GEN2,
>  ARCH_RCAR_GEN3, ARCH_RCAR_GEN4, ARCH_RMOBILE, ARCH_RZG2L, ARCH_RZN1
> Family SOCs and rest of the individual SoCs such as RZ/V2H abnd RZ/g3E.


Rather tell me why this is supposed to be different than other vendors?

|| ARM64 is already used solution

> 
> Since most of IP's in RZ/V2H and RZ/G3E are identical we could introduce 
> a new family SoC ARCH_RZG3E_RZV2H to cover both or top level ARCH_RENESAS??

You should not write drivers per SoCs (or even two or there SoCs) and
there is really no need to restrict them per each SoC.

Otherwise come with arguments to my first question: why do you need
exception here from generic kernel approach?


Best regards,
Krzysztof