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

Konrad Dybcio konrad.dybcio at oss.qualcomm.com
Wed Nov 5 01:14:37 PST 2025


On 11/5/25 8:53 AM, Charan Teja Kalla wrote:
> Add ACTLR settings for the device nodes with below compatibility
> and is mainly targeted for sa8775p:

The commit subject should mention it's the lemans MDSS specifically
> 1) sa8775p-mdss
> 2) qcom,fastrpc-compute-cb
> 
> As a side note, "qcom,fastrpc" compatibility is already defined but that
> seems inept as the devices that will be attached to the SMMU is going to
> be with "qcom,fastrpc-compute-cb" compat string.

If you say it's a NOP after all, please split the fastrpc change into
a separate commit explaining the issue and removing the wrong entry

> Signed-off-by: Charan Teja Kalla <charan.kalla at oss.qualcomm.com>
> ---
>  drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> index c21a401c71eb..c76f6076f487 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> @@ -47,6 +47,10 @@ static const struct of_device_id qcom_smmu_actlr_client_of_match[] = {
>  			.data = (const void *) (PREFETCH_SHALLOW | CPRE | CMTLB) },
>  	{ .compatible = "qcom,sm8550-mdss",
>  			.data = (const void *) (PREFETCH_DEFAULT | CMTLB) },
> +	{ .compatible = "qcom,sa8775p-mdss",
> +			.data = (const void *) (PREFETCH_DEFAULT | CMTLB) },

This list should be sorted alphanumerically

> +	{ .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?

Konrad



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