Re: [PATCH] iommu/arm-smmu: add actlr settings for mdss and fastrpc

From: Charan Teja Kalla

Date: Tue Nov 11 2025 - 09:02:41 EST




On 11/5/2025 2:44 PM, Konrad Dybcio wrote:
>> + { .compatible = "qcom,fastrpc-compute-cb",
>> + .data = (const void *) (PREFETCH_DEEP | CPRE | CMTLB) },
> This will be globally applied to all smmu-v2 targets with fastrpc,
> starting from MSM8996 ending at Kaanapali and everything inbetween
>
> Are these settings always valid?
Oops, you are correct...this settings are not always applicable it seems.

Example: lpass compute and cdsp compute node uses the
"qcom,fastrpc-compute-cb", but it is for the later that ACTLR settings
are valid.

Then for these cases, should we be extending the actlr match array with
additional compatible string and then add them in all the device nodes
that require actlr setting? example:

@@ -3119,7 +3119,8 @@ fastrpc {
compute-cb@1 {
- compatible = "qcom,fastrpc-compute-cb";
+ compatible = "qcom,fastrpc-compute-cb",
+ "qcom,fastrpc-compute-cb-actlr";


--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -49,7 +49,7 @@ static const struct of_device_id
qcom_smmu_actlr_client_of_match[] = {
+ { .compatible = "qcom,fastrpc-compute-cb-actlr",
.data = (const void *) (PREFETCH_DEEP | CPRE |
CMTLB) },
{ }


or any other better way, please lmk.

Thanks,
Charan