Re: [PATCH v6] iommu/arm-smmu-qcom: Request direct mapping for modem device

[Bjorn Andersson]

On Mon 11 May 10:55 PDT 2020, Sibi Sankar wrote:

> The modem remote processor has two access paths to DDR. One path is
> directly connected to DDR and another path goes through an SMMU. The
> SMMU path is configured to be a direct mapping because it's used by
> various peripherals in the modem subsystem. Typically this direct
> mapping is configured statically at EL2 by QHEE (Qualcomm's Hypervisor
> Execution Environment) before the kernel is entered.
> 
> In certain firmware configuration, especially when the kernel is already
> in full control of the SMMU, defer programming the modem SIDs to the
> kernel. Let's add compatibles here so that we can have the kernel
> program the SIDs for the modem in these cases.
> 

Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>

Regards,
Bjorn

> Signed-off-by: Sibi Sankar <sibis@xxxxxxxxxxxxxx>
> ---
> 
> V6
>  * Rebased on Will's for-joerg/arm-smmu/updates
>  * Reword commit message and add more details [Stephen]
> 
>  drivers/iommu/arm-smmu-qcom.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/iommu/arm-smmu-qcom.c b/drivers/iommu/arm-smmu-qcom.c
> index 5bedf21587a56..cf01d0215a397 100644
> --- a/drivers/iommu/arm-smmu-qcom.c
> +++ b/drivers/iommu/arm-smmu-qcom.c
> @@ -17,7 +17,9 @@ static const struct of_device_id qcom_smmu_client_of_match[] = {
>  	{ .compatible = "qcom,mdp4" },
>  	{ .compatible = "qcom,mdss" },
>  	{ .compatible = "qcom,sc7180-mdss" },
> +	{ .compatible = "qcom,sc7180-mss-pil" },
>  	{ .compatible = "qcom,sdm845-mdss" },
> +	{ .compatible = "qcom,sdm845-mss-pil" },
>  	{ }
>  };
>  
> -- 
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