Re: [PATCH v3 1/3] dt-bindings: reset: Add Armada8K reset controller

[Krzysztof Kozlowski <krzk@kernel.org>]

On 07/03/2025 01:03, Wilson Ding wrote:
>> reset.example.dts
>>>   DTC [C]
>>> Documentation/devicetree/bindings/reset/marvell,armada8k-reset.example
>>> .dtb
>>>
>>
>> That's a bit odd but anyway warning is correct: you cannot have such
>> compatibles alone.
> 
> I understand I need to add one compatible here to resolve the
> warning. However, as we agreed, we keep the sud-nodes while
> there will be no new compatibles in parent node. So how shall
> I avoid this warning?
> 
> If we do want to add a compatible in parent node, what should
> be used for the compatible name? I think the most suitable name
> would be something like "marvell,cp110-system-controller0".

I don't know. I don't work in Marvell, I know nothing about Marvell
Armada and I was not involved in any Armada SoCs.

Read your datasheet and come up with some reasonable name based on
datasheet. Why do you ask people who do not have datasheet?

> However, it was already taken for in Armada clock controller to
> be compatible for legacy dt.
> 
> https://lore.kernel.org/all/bb21ee9acc55efac884450ff710049b99b27f8bf.1496328934.git-series.gregory.clement@free-electrons.com/

I don't understand what it means.

> 
> This is something about 8 years ago. I wonder if we do need to
> have the backward compatibility for the field devices at that
> time. Can we drop it now?

Drop what? You need to keep ABI.

> 
>     syscon0: system-controller@440000 {
>         compatible = "marvell,cp110-system-controller0",
>                                 "syscon", "simple-mfd";
>         reg = <0x440000 0x2000>;
>         #address-cells = <1>;
>         #size-cells = <1>;
> 
>         swrst: reset-controller@268 {
>             compatible = "marvell,armada8k-reset";
>             reg = <0x268 0x4>;
>             #reset-cells = <1>;
>         };
>     };
> 
Best regards,
Krzysztof