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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <eb596f7a-e13b-4edd-8ee7-05424ea3d9e5@oss.qualcomm.com>
Date: Wed, 5 Nov 2025 10:14:37 +0100
From: Konrad Dybcio <konrad.dybcio@....qualcomm.com>
To: Charan Teja Kalla <charan.kalla@....qualcomm.com>,
        robin.clark@....qualcomm.com, will@...nel.org, robin.murphy@....com,
        joro@...tes.org, dmitry.baryshkov@....qualcomm.com
Cc: iommu@...ts.linux.dev, linux-arm-msm@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] iommu/arm-smmu: add actlr settings for mdss and fastrpc

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@....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