Re: [PATCH 3/3] dt-bindings: riscv: sifive: Add SiFive Private L2 cache controller

From: Krzysztof Kozlowski
Date: Sat Jul 01 2023 - 04:22:33 EST


On 28/06/2023 18:31, Eric Lin wrote:

>>>>
>>>>> + - enum:
>>>>> + - sifive,pL2Cache0
>>>>> + - sifive,pL2Cache1
>>>>
>>>> What is "0" and "1" here? What do these compatibles represent? Why they
>>>> do not have any SoC related part?
>>>
>>> The pL2Cache1 has minor changes in hardware, but it can use the same
>>> pl2 cache driver.
>>
>> Then why aren't they compatible?
>>
>
> The pL2Cache1 has removed some unused bits in the register compared to
> pl2Cache0.
> From the hardware perspective, they are not compatible but they can
> share the same pl2 cache driver in software.

So they are compatible... If they were not compatible, you wouldn't be
able to use the same match in the driver.

> Thus, we would like to keep both. It would be great if you can provide
> some suggestions. Thanks.

I propose to make them compatible, like every other piece of SoC. I
don't see any benefit of having them separate.

Best regards,
Krzysztof