Re: [PATCH v1 12/27] dt-bindings: gpu: panthor: Document panthor-arbitration bindings

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Low] dt-bindings: hardcoded driver-specific node name 'panthor-arbitration'
- [Low] dt-bindings: missing const constraints on #address-cells and #size-cells
--

commit 5958d9241a2d1add1102ff00e882946446a4e494
Author: Karunika Choo <karunika.choo@arm.com>

dt-bindings: gpu: panthor: Document panthor-arbitration bindings

Mali 5th-Gen AM GPUs expose arbitration registers outside the GPU node.
The arbitration device contains partition-control and resource-group
register blocks used to grant, yield, and close access windows.

Document partition and resource-group child nodes, each with its own
register range, interrupt and hardware ID.

> diff --git a/Documentation/devicetree/bindings/gpu/arm,mali-gen5-am-arbitration.yaml b/Documentation/devicetree/bindings/gpu/arm,mali-gen5-am-arbitration.yaml
> new file mode 100644
> index 0000000000000..9ea2b4bb9a344
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpu/arm,mali-gen5-am-arbitration.yaml

[ ... ]

> +properties:
> +  $nodename:
> +    const: panthor-arbitration

[Severity: Low]
Does this enforce an invalid, driver-specific naming convention on all
devicetrees using this hardware?

Any devicetree author attempting to instantiate this hardware must use the
Linux-specific driver name panthor-arbitration to pass schema validation.
This violates the DT specification requirement for generic,
hardware-reflective naming. 

Could this be changed to use a generic term like arbitrator or
gpu-arbitrator instead of incorporating the DRM driver name?

> +
> +  compatible:
> +    const: arm,mali-gen5-am-arbitration
> +
> +  "#address-cells": true
> +
> +  "#size-cells": true

[Severity: Low]
Should these cell-count properties have a strict const constraint matching
the hardware, such as const: 1 as shown in the examples, rather than just
true?

Without a strict constraint, the schema allows arbitrary integers for cell
counts. This weakens schema validation for child nodes' reg array dimensions,
and a device tree with incorrectly sized reg properties might silently pass
the dt_binding_check.

> +
> +  ranges: true

[ ... ]

> diff --git a/Documentation/devicetree/bindings/gpu/arm,mali-gen5-am-system.yaml b/Documentation/devicetree/bindings/gpu/arm,mali-gen5-am-system.yaml
> index f0689bb8f05a2..a027dc5f4f890 100644
> --- a/Documentation/devicetree/bindings/gpu/arm,mali-gen5-am-system.yaml
> +++ b/Documentation/devicetree/bindings/gpu/arm,mali-gen5-am-system.yaml

[ ... ]

> @@ -41,6 +41,15 @@ properties:
>  
>    dma-coherent: true
>  
> +  "#address-cells": true
> +
> +  "#size-cells": true

[Severity: Low]
Similar to the arbitration bindings, should these cell-count properties also
be defined with strict const constraints?

Allowing arbitrary integers weakens schema validation for child nodes' reg
array dimensions.

> +
> +  ranges: true
> +
> +  panthor-arbitration:
> +    $ref: arm,mali-gen5-am-arbitration.yaml#

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260922204535.2850094-1-karunika.choo@arm.com?part=12