Re: [Freedreno] [PATCH 16/17] iommu: remove DOMAIN_ATTR_IO_PGTABLE_CFG
From: Will Deacon <will@kernel.org>
Date: 2021-03-05 10:01:15
Also in:
dri-devel, kvm, linux-arm-kernel, linux-arm-msm, linux-iommu, linuxppc-dev, virtualization
On Thu, Mar 04, 2021 at 03:11:08PM -0800, Rob Clark wrote:
On Thu, Mar 4, 2021 at 7:48 AM Robin Murphy [off-list ref] wrote:quoted
On 2021-03-01 08:42, Christoph Hellwig wrote:quoted
Signed-off-by: Christoph Hellwig <hch@lst.de>Moreso than the previous patch, where the feature is at least relatively generic (note that there's a bunch of in-flight development around DOMAIN_ATTR_NESTING), I'm really not convinced that it's beneficial to bloat the generic iommu_ops structure with private driver-specific interfaces. The attribute interface is a great compromise for these kinds of things, and you can easily add type-checked wrappers around it for external callers (maybe even make the actual attributes internal between the IOMMU core and drivers) if that's your concern.I suppose if this is *just* for the GPU we could move it into adreno_smmu_priv.. But one thing I'm not sure about is whether IO_PGTABLE_QUIRK_ARM_OUTER_WBWA is something that other devices *should* be using as well, but just haven't gotten around to yet.
The intention is certainly that this would be a place to collate per-domain pgtable quirks, so I'd prefer not to tie that to the GPU. Will