Re: [PATCH v2 1/1] dt-bindings: remoteproc: mtk,scp: Allow multiple memory regions for MT8188

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Schema constraint override failure for `memory-region` maxItems
--

commit 609e858e4a4e669b55ac4136f210e50fe09b79a7
Author: Arnab Layek <arnab.layek@mediatek.com>

dt-bindings: remoteproc: mtk,scp: Allow multiple memory regions for MT8188

This commit attempts to allow up to two memory regions for MT8188
compatibles by adding an if/then block. The new regions are
documented with descriptions for the main SCP SRAM and the optional
SCP L1TCM.

> diff --git a/Documentation/devicetree/bindings/remoteproc/mtk,scp.yaml b/Documentation/devicetree/bindings/remoteproc/mtk,scp.yaml
> index bdbb12118da43..df13be2026a67 100644
> --- a/Documentation/devicetree/bindings/remoteproc/mtk,scp.yaml
> +++ b/Documentation/devicetree/bindings/remoteproc/mtk,scp.yaml

[ ... ]

> @@ -205,6 +205,27 @@ allOf:
>            items:
>              - const: cfg
>              - const: l1tcm
> +  - if:
> +      properties:
> +        compatible:
> +          enum:
> +            - mediatek,mt8188-scp
> +            - mediatek,mt8188-scp-dual
> +    then:
> +      properties:
> +        memory-region:
> +          minItems: 1
> +          items:
> +            - description: Main SCP SRAM memory region
> +            - description: Optional SCP L1TCM memory region

Does this code introduce a regression where 2 items are not actually allowed
for these compatibles?

In dt-schema, constraints are evaluated additively. The base schema
explicitly defines maxItems: 1 for memory-region. Because an if/then
block cannot override or relax a stricter constraint from the base schema,
a device tree specifying 2 memory regions for mediatek,mt8188-scp will
still violate the base maxItems: 1 constraint and fail dt_binding_check.

Does the global constraint need to be increased to maxItems: 2, and then
maxItems: 1 enforced selectively for other SoCs via conditional blocks?

> +      patternProperties:
> +        "^scp@[a-f0-9]+$":
> +          properties:
> +            memory-region:
> +              minItems: 1
> +              items:
> +                - description: Main SCP SRAM memory region
> +                - description: Optional SCP L1TCM memory region

Does this patternProperties block have the same regression?

The base patternProperties block for ^scp@[a-f0-9]+$ also defines
maxItems: 1 for memory-region, which would likewise prevent this
conditional block from allowing multiple items.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260511121004.2984149-2-arnab.layek@mediatek.com?part=1