[PATCH v10 11/13] iommu/arm-smmu-v3: Add SVA device feature

Krishna Reddy vdumpa at nvidia.com
Mon Dec 14 20:09:29 EST 2020


Hi Jean,

> +bool arm_smmu_master_sva_supported(struct arm_smmu_master *master) {
> +       if (!(master->smmu->features & ARM_SMMU_FEAT_SVA))
> +               return false;
+
> +       /* SSID and IOPF support are mandatory for the moment */
> +       return master->ssid_bits && arm_smmu_iopf_supported(master); }
> +

Tegra Next Gen SOC has arm-smmu-v3 and It doesn't have support for PRI interface.
However, PCIe client device has capability to handle the page faults on its own when the ATS translation fails.
The PCIe device needs SVA feature enable without PRI interface supported at arm-smmu-v3.
At present, the SVA feature enable is allowed only if the smmu/client device has PRI support. 
There seem to be no functional reason to make pri_supported as a pre-requisite for SVA enable.
Can SVA enable be supported for pri_supported not set case as well? 
Also, It is noticed that SVA  enable on Intel doesn't need pri_supported set. 

-KR



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