RE: [PATCH v10 10/13] iommu/arm-smmu-v3: Check for SVA features

Krishna Reddy
2020-12-14T23:24:44Z

>> The Tegra Next Generation SOC uses arm-smmu-v3, but it doesn't have support for BTM.
>> Do you have plan to get your earlier patch to handle invalidate notifications into upstream sometime soon?
>> Can the dependency on BTM be relaxed with the patch?
>>
>> PATCH v9 13/13] iommu/arm-smmu-v3: Hook up ATC invalidation to mm ops
>> https://www.spinics.net/lists/arm-kernel/msg825099.html

>This patch (which should be in 5.11) only takes care of sending ATC invalidations to PCIe endpoints. With this, BTM is still required to invalidate SMMU TLBs.
> However we could enable command-queue invalidation when ARM_SMMU_FEAT_BTM isn't set.
> Invalidations are still a relatively rare event so it may not be outrageously slow. I can add a patch to my tree if you have hardware to test.

Thanks! We can test the patch on emulation platform.

-KR