[PATCH 1/3] dt-bindings: arm-smmu: Add interconnect for qcom SMMUs

Krzysztof Kozlowski krzysztof.kozlowski at linaro.org
Fri Jun 9 06:23:15 PDT 2023


On 09/06/2023 07:41, Parikshit Pareek wrote:
> There are certain SMMUs on qcom SoCs, which need to set interconnect-
> bandwidth, before accessing any MIMO mapped HW registers, and accessing
> RAM during page table walk. Hence introduce the due bindings for
> interconnects.
> 
> Reported-by: Eric Chanudet <echanude at redhat.com>

What is reported here exactly? What is the bug?

> Signed-off-by: Parikshit Pareek <quic_ppareek at quicinc.com>
> ---
>  .../devicetree/bindings/iommu/arm,smmu.yaml   | 22 +++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
> index ba677d401e24..75e00789d8c2 100644
> --- a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
> +++ b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
> @@ -327,6 +327,28 @@ allOf:
>              - description: interface clock required to access smmu's registers
>                  through the TCU's programming interface.
>  
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              qcom,sa8775p-smmu-500
> +    then:
> +      properties:
> +        interconnects:
> +          minItems: 1

Drop minItems

> +          maxItems: 1
> +
> +        interconnect-names:
> +          minItems: 1

??? Drop

> +          items:
> +            - const: tbu_mc

Anyway, properties must be defined in top-level. In if block you only
customize them.

> +
> +        icc_bw:
> +          $ref: /schemas/types.yaml#/definitions/int32

No, for multiple reasons. First - do not define properties in if: block.
Second, does not look like description of hardware. I actually don't
understand what is this for. :(

Best regards,
Krzysztof




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