Re: [PATCH v4 1/3] dt-bindings: remoteproc: Move iommus constraint to SoC-specific bindings

[Komal Bajaj <komal.bajaj@oss.qualcomm.com>]

On 11/5/2026 7:05 PM, Krzysztof Kozlowski wrote:
> On Wed, Nov 04, 2026 at 07:33:30PM +0530, Komal Bajaj wrote:
>> The `iommus` property constraint in qcom,pas-common.yaml is too
>> restrictive with `maxItems: 1`, preventing SoCs that require multiple
>> IOMMU entries from being properly described.
>   From here
>
>> Remove `iommus` constraint from qcom,pas-common.yaml and add it to
>> SoC-specific binding files that have EL2 support and require IOMMU
>> configuration:
>>
>> - qcom,sa8775p-pas.yaml: Add `iommus: maxItems: 1` for all sa8775p
>>    and qcs8300 remoteproc compatibles (lemans-el2, monaco-el2)
>>
>> - qcom,sm8150-pas.yaml: Add `iommus: maxItems: 1` for qcs615
>>    remoteproc compatibles (talos-el2)
>>
>> - qcom,sm8550-pas.yaml: Add `iommus: maxItems: 1` for x1e80100
>>    remoteproc compatibles (x1-el2)
> to here - all this repeats the diff.

Sure, I will drop them and keep only the reason for the change, and why 
the SoC bindings now need to declare iommus themselves, in the next 
revision.

>
>> This allows each SoC to define its own IOMMU requirements while
>> maintaining backward compatibility.
>>
>> Signed-off-by: Komal Bajaj <komal.bajaj@oss.qualcomm.com>
>> ---
>>   .../devicetree/bindings/remoteproc/qcom,pas-common.yaml      |  3 ---
>>   .../devicetree/bindings/remoteproc/qcom,sa8775p-pas.yaml     |  6 ++++++
>>   .../devicetree/bindings/remoteproc/qcom,sm8150-pas.yaml      | 12 ++++++++++++
>>   .../devicetree/bindings/remoteproc/qcom,sm8550-pas.yaml      | 12 ++++++++++++
> While you are not answering the unknown - what about all other devices?

I checked all users of qcom,pas-common.yaml, including DTS files for PAS 
remoteproc nodes using iommus, and ran dtbs_check on the arm64 qualcomm 
DTBs.
The only affected user outside this series is Glymur, where glymur.dtsi 
specifies iommus for ADSP and CDSP nodes. I will add the corresponding 
constraint to sm8550 binding in next revision.

>
>>   4 files changed, 30 insertions(+), 3 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/remoteproc/qcom,pas-common.yaml b/Documentation/devicetree/bindings/remoteproc/qcom,pas-common.yaml
>> index f75cab6b4ed9..4662fe4cff62 100644
>> --- a/Documentation/devicetree/bindings/remoteproc/qcom,pas-common.yaml
>> +++ b/Documentation/devicetree/bindings/remoteproc/qcom,pas-common.yaml
>> @@ -32,9 +32,6 @@ properties:
>>       minItems: 5
>>       maxItems: 6
>>   
>> -  iommus:
>> -    maxItems: 1
>> -
>>     power-domains:
>>       minItems: 1
>>       maxItems: 3
>> diff --git a/Documentation/devicetree/bindings/remoteproc/qcom,sa8775p-pas.yaml b/Documentation/devicetree/bindings/remoteproc/qcom,sa8775p-pas.yaml
>> index dda2d144b720..711c2f723b17 100644
>> --- a/Documentation/devicetree/bindings/remoteproc/qcom,sa8775p-pas.yaml
>> +++ b/Documentation/devicetree/bindings/remoteproc/qcom,sa8775p-pas.yaml
>> @@ -106,6 +106,8 @@ allOf:
>>             items:
>>               - const: lcx
>>               - const: lmx
>> +        iommus:
>> +          maxItems: 1
> Missing property definition in top-level.

  Agreed. I will define iommus once in top-level properties of 
qcom,sa8775p-pas.yaml and drop repeated entries from allOf conditions in 
next revision.

Thanks
Komal

>
>>   
>>     - if:
>>         properties:
>> @@ -126,6 +128,8 @@ allOf:
>>               - const: cx
>>               - const: mxc
>>               - const: nsp
>> +        iommus:
>> +          maxItems: 1
>>   
>>     - if:
>>         properties:
>> @@ -144,6 +148,8 @@ allOf:
>>             items:
>>               - const: cx
>>               - const: mxc
>> +        iommus:
>> +          maxItems: 1
> Not sure what is the point of repeating it multiple times.
>
> Best regards,
> Krzysztof
>