Re: [PATCH 1/9] dt-bindings: Add arm,mali-valhall compatible

[Robin Murphy <robin.murphy@xxxxxxx>]

On 2022-02-11 20:27, alyssa.rosenzweig@xxxxxxxxxxxxx wrote:
> From: Alyssa Rosenzweig <alyssa.rosenzweig@xxxxxxxxxxxxx>
>
>  From the kernel's perspective, pre-CSF Valhall is more or less
> compatible with Bifrost, although they differ to userspace. Add a
> compatible for Valhall to the existing Bifrost bindings documentation.
>
> Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@xxxxxxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx
> ---
>   Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml b/Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml
> index 63a08f3f321d..48aeabd2ed68 100644
> --- a/Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml
> +++ b/Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml
> @@ -23,6 +23,7 @@ properties:
>             - rockchip,px30-mali
>             - rockchip,rk3568-mali
>         - const: arm,mali-bifrost # Mali Bifrost GPU model/revision is fully discoverable
> +      - const: arm,mali-valhall # Mali Valhall GPU model/revision is fully discoverable

This requires all existing Bifrost users to add the Valhall compatible 
as well - I don't think that's what you want. From what we tossed about 
on IRC the other week, I'd imagined something more in the shape of:

  compatible:
    oneOf:
      - items:
          - enum:
              - vendor,soc-mali
              - ...
          - const: arm,mali-bifrost
      - items:
          - enum:
              - vendor,soc-mali
              - ...
          - const: arm,mali-valhall
          - const: arm,mali-bifrost #or not, depending on 
forward-compatibility preferences

Cheers,
Robin.