Re: [PATCH v12 00/13] iommu/arm-smmu: Add Adreno SMMU specific implementation

From: Will Deacon
Date: Thu Aug 13 2020 - 09:19:45 EST


On Mon, Aug 10, 2020 at 04:26:44PM -0600, Jordan Crouse wrote:
> This series adds an Adreno SMMU implementation to arm-smmu to allow GPU hardware
> pagetable switching.
>
> The Adreno GPU has built in capabilities to switch the TTBR0 pagetable during
> runtime to allow each individual instance or application to have its own
> pagetable. In order to take advantage of the HW capabilities there are certain
> requirements needed of the SMMU hardware.

"capabilities" is a polite way of putting it ;)

Anyway, modulo two design comments, I think this is about as nice as we're
going to get this. Thanks for persevering, and sorry that you have to deal
with such dreadful hardware.

Hopefully the next version will be the one, although I'd like Robin to take
a quick look as well if he gets a chance.

Will