Re: [PATCH] iommu/arm-smmu-qcom: Fix fastrpc compatible in ACTLR client match table

[Dmitry Baryshkov]

On Thu, Apr 16, 2026 at 11:26:52PM +0800, Shawn Guo wrote:
> The qcom_smmu_actlr_client_of_match table used "qcom,fastrpc" as the
> compatible to configure ACTLR for fastrpc SMMU clients.  However, the
> "qcom,fastrpc" compatible identifies the fastrpc transport (glink)
> device, which does not have an iommus property and thus never attaches
> to the SMMU directly.
> 
> The actual SMMU clients are the per-channel compute context bank (CB)
> devices, which use the "qcom,fastrpc-compute-cb" compatible and each
> carry their own iommus property.  Replace the compatible string so that
> ACTLR prefetch and caching settings are applied to the right devices.
> 
> Fixes: 3e35c3e725de ("iommu/arm-smmu: Add ACTLR data and support for qcom_smmu_500")
> Signed-off-by: Shawn Guo <shengchao.guo@xxxxxxxxxxxxxxxx>

https://lore.kernel.org/r/20260408130825.3268733-1-bibek.patro@xxxxxxxxxxxxxxxx

> ---
>  drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> index edd41b5a3b6a..2d006049dd61 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> @@ -39,7 +39,7 @@ static const struct of_device_id qcom_smmu_actlr_client_of_match[] = {
>  			.data = (const void *) (PREFETCH_DEEP | CPRE | CMTLB) },
>  	{ .compatible = "qcom,adreno-smmu",
>  			.data = (const void *) (PREFETCH_DEEP | CPRE | CMTLB) },
> -	{ .compatible = "qcom,fastrpc",
> +	{ .compatible = "qcom,fastrpc-compute-cb",
>  			.data = (const void *) (PREFETCH_DEEP | CPRE | CMTLB) },
>  	{ .compatible = "qcom,qcm2290-mdss",
>  			.data = (const void *) (PREFETCH_SHALLOW | CPRE | CMTLB) },
> -- 
> 2.43.0
> 

-- 
With best wishes
Dmitry