Re: [PATCH v3 5/7] dt-bindings: gpu: v3d: Add SMS register to BCM2712 compatible

[Rob Herring <robh@kernel.org>]

On Tue, Mar 11, 2025 at 03:13:47PM -0300, Maíra Canal wrote:
> V3D 7.1 exposes a new register block, called V3D_SMS. As BCM2712 has a
> V3D 7.1 core, add a new register item to its compatible. Similar to the
> GCA, which is specific for V3D 3.3, SMS is optional and should only be
> added for V3D 7.1 variants (such as brcm,2712-v3d).

Based on the schema, that is not what optional means for bindings. 
Optional is within a specific compatible, not present for one compatible 
and not present for another compatible.

> 
> Signed-off-by: Maíra Canal <mcanal@igalia.com>
> ---
>  .../devicetree/bindings/gpu/brcm,bcm-v3d.yaml      | 22 +++++++++++++++++++++-
>  1 file changed, 21 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.yaml b/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.yaml
> index 141f2ed540bb4ddb85a933d7d44a4078c386ba39..7349347da1c0034a8849deaa6d64dde6d9d5a81a 100644
> --- a/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.yaml
> +++ b/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.yaml
> @@ -57,7 +57,6 @@ allOf:
>            contains:
>              enum:
>                - brcm,2711-v3d
> -              - brcm,2712-v3d
>                - brcm,7278-v3d
>      then:
>        properties:
> @@ -71,6 +70,27 @@ allOf:
>              - const: hub
>              - const: core0
>              - const: bridge
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: brcm,2712-v3d
> +    then:
> +      properties:
> +        reg:
> +          items:
> +            - description: hub register (required)
> +            - description: core0 register (required)
> +            - description: SMS register (required)

minItems tells us these are all 'required'.

> +            - description: bridge register (if no external reset controller)
> +          minItems: 3
> +        reg-names:
> +          items:
> +            - const: hub
> +            - const: core0
> +            - const: sms
> +            - const: bridge

This is an ABI change because previously the 3rd entry was bridge and 
you moved it. Put new entries on the end to keep compatibility. If 
there's no users yet, then that's fine, but the commit message needs to 
say that.

> +          minItems: 3
>    - if:
>        properties:
>          compatible:
> 
> -- 
> Git-154)
>