Re: [PATCH v2 1/6] dt-bindings: arm-smmu: Use qcom,smmu compatible for MMU500 adreno SMMUs

[Konrad Dybcio]

On 26.02.2023 18:37, Rob Herring wrote:
> On Fri, Feb 17, 2023 at 12:16:08PM +0100, Konrad Dybcio wrote:
>> qcom,smmu-500 was introduced to prevent people from adding new
>> compatibles for what seems to roughly be the same hardware. Use it for
>> qcom,adreno-smmu-compatible targets as well.
>>
>> Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
>> ---
>> v1 -> v2:
>> - Add this patch, omitted previously (big oops)
>>
>>  .../devicetree/bindings/iommu/arm,smmu.yaml        | 14 ++++++++++++--
>>  1 file changed, 12 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
>> index 807cb511fe18..4d7f61700cae 100644
>> --- a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
>> +++ b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
>> @@ -75,9 +75,19 @@ properties:
>>                - qcom,sm8350-smmu-500
>>                - qcom,sm8450-smmu-500
>>            - const: arm,mmu-500
>> -
>> -      - description: Qcom Adreno GPUs implementing "arm,smmu-500"
>> +      - description: Qcom Adreno GPUs implementing "qcom,smmu-500" and "arm,smmu-500"
>> +        items:
>> +          - enum:
>> +              - qcom,sc7280-smmu-500
>> +              - qcom,sm8150-smmu-500
>> +              - qcom,sm8250-smmu-500
>> +          - const: qcom,adreno-smmu
>> +          - const: qcom,smmu-500
>> +          - const: arm,mmu-500
> 
> 4 compatibles seems excessive. Is adding one that helpful? Is 
> 'arm,mmu-500' useful on its own?
Yes.

per-soc compatible is there for per-soc quirks should there be any
qcom,adreno-smmu enabled per-process pagetables
qcom,smmu-500 matches the qcom smmu implementation
arm,mmu-500 matches the smmu driver as a whole

> 
>> +      - description: Qcom Adreno GPUs implementing "arm,smmu-500" (legacy binding)
> 
> Perhaps fix the existing typo: arm,mmu-500
Ack

Konrad
> 
>> +        deprecated: true
>>          items:
>> +          # Do not add additional SoC to this list. Instead use previous list.
>>            - enum:
>>                - qcom,sc7280-smmu-500
>>                - qcom,sm8150-smmu-500
>> -- 
>> 2.39.1
>>