[v2] dt-bindings: arm-smmu: Constrain clocks for newer Qualcomm variants

[PATCH v2] dt-bindings: arm-smmu: Constrain clocks for newer Qualcomm variants

Posted by Krzysztof Kozlowski 5 days, 19 hours ago

Many of SMMU on Qualcomm SoCs come in two flavors using the same front
compatible but a bit different fallback:

1. For application processor, usually without any controllable
   clocks,

2. For the Adreno GPU, with some controllable clock(s) and using
   additionally qcom,adreno-smmu fallback compatible.

Add missing constraints for Glymur SMMU on Adreno GPU and several other
Qualcomm SMMUs for application processors, to restrict the clocks
property to a specific length.

Acked-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Shawn Guo <shengchao.guo@oss.qualcomm.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

---

Changes in v2:
1. Tags
2. Fix grammar in commit msg
---
 .../devicetree/bindings/iommu/arm,smmu.yaml   | 38 ++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
index 06fb5c8e7547..ed0d10157bd6 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
@@ -566,7 +566,9 @@ allOf:
       properties:
         compatible:
           items:
-            - const: qcom,sm8750-smmu-500
+            - enum:
+                - qcom,glymur-smmu-500
+                - qcom,sm8750-smmu-500
             - const: qcom,adreno-smmu
             - const: qcom,smmu-500
             - const: arm,mmu-500
@@ -595,6 +597,7 @@ allOf:
               - qcom,sdm845-smmu-500
               - qcom,sdx55-smmu-500
               - qcom,sdx65-smmu-500
+              - qcom,sdx75-smmu-500
               - qcom,sm6350-smmu-500
               - qcom,sm6375-smmu-500
     then:
@@ -602,6 +605,39 @@ allOf:
         clock-names: false
         clocks: false
 
+  # Disallow clocks for all other platforms where specific compatible is used
+  # with different fallbacks and only one combination has no clocks
+  - if:
+      properties:
+        compatible:
+          items:
+            - enum:
+                - qcom,eliza-smmu-500
+                - qcom,glymur-smmu-500
+                - qcom,kaanapali-smmu-500
+                - qcom,milos-smmu-500
+                - qcom,qcs615-smmu-500
+                - qcom,qcs8300-smmu-500
+                - qcom,sa8775p-smmu-500
+                - qcom,sm6115-smmu-500
+                - qcom,sm6125-smmu-500
+                - qcom,sm6350-smmu-500
+                - qcom,sm6375-smmu-500
+                - qcom,sm8150-smmu-500
+                - qcom,sm8250-smmu-500
+                - qcom,sm8350-smmu-500
+                - qcom,sm8450-smmu-500
+                - qcom,sm8550-smmu-500
+                - qcom,sm8650-smmu-500
+                - qcom,sm8750-smmu-500
+                - qcom,x1e80100-smmu-500
+            - const: qcom,smmu-500
+            - const: arm,mmu-500
+    then:
+      properties:
+        clock-names: false
+        clocks: false
+
   - if:
       properties:
         compatible:
-- 
2.51.0

Re: [PATCH v2] dt-bindings: arm-smmu: Constrain clocks for newer Qualcomm variants

Posted by Will Deacon 5 days, 11 hours ago

On Tue, 19 May 2026 09:41:00 +0200, Krzysztof Kozlowski wrote:
> Many of SMMU on Qualcomm SoCs come in two flavors using the same front
> compatible but a bit different fallback:
> 
> 1. For application processor, usually without any controllable
>    clocks,
> 
> 2. For the Adreno GPU, with some controllable clock(s) and using
>    additionally qcom,adreno-smmu fallback compatible.
> 
> [...]

!! Please note: this conflicted with the Glymur GPU bindings update. That
   was trivial to fix, but I've also queued an update adding
   "qcom,shikra-smmu-500" which you may want in your list of platforms
   where clocks are disallowed?

Applied to iommu (arm/smmu/bindings), thanks!

[1/1] dt-bindings: arm-smmu: Constrain clocks for newer Qualcomm variants
      https://git.kernel.org/iommu/c/75949eb02653

Cheers,
-- 
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev

Re: [PATCH v2] dt-bindings: arm-smmu: Constrain clocks for newer Qualcomm variants

Posted by Krzysztof Kozlowski 5 days, 6 hours ago

On 19/05/2026 17:23, Will Deacon wrote:
> On Tue, 19 May 2026 09:41:00 +0200, Krzysztof Kozlowski wrote:
>> Many of SMMU on Qualcomm SoCs come in two flavors using the same front
>> compatible but a bit different fallback:
>>
>> 1. For application processor, usually without any controllable
>>    clocks,
>>
>> 2. For the Adreno GPU, with some controllable clock(s) and using
>>    additionally qcom,adreno-smmu fallback compatible.
>>
>> [...]
> 
> !! Please note: this conflicted with the Glymur GPU bindings update. That
>    was trivial to fix, but I've also queued an update adding
>    "qcom,shikra-smmu-500" which you may want in your list of platforms
>    where clocks are disallowed?
> 

Thanks, I will double check and send a followup if needed.

Best regards,
Krzysztof