This is a new refresh of support for auxiliary domains for arm-smmu-v2 and per-instance pagetables for drm/msm. The big change here from past efforts is that outside of creating a single aux-domain to enable TTBR0 all of the per-instance pagetables are created and managed exclusively in drm/msm without involving the arm-smmu driver. This fits in with the suggested model of letting the GPU hardware do what it needs and leave the arm-smmu driver blissfully unaware.
Almost. In order to set up the io-pgtable properly in drm/msm we need to query the pagetable configuration from the current active domain and we need to rely on the iommu API to flush TLBs after a unmap. In the future we can optimize this in the drm/msm driver to track the state of the TLBs but for now the big hammer lets us get off the ground.
This series is built on the split pagetable support [1].
[1] https://patchwork.kernel.org/patch/11628543/
v2: Remove unneeded cruft in the a6xx page switch sequence
Jordan Crouse (6): iommu/arm-smmu: Add auxiliary domain support for arm-smmuv2 iommu/io-pgtable: Allow a pgtable implementation to skip TLB operations iommu/arm-smmu: Add a domain attribute to pass the pagetable config drm/msm: Add support to create a local pagetable drm/msm: Add support for address space instances drm/msm/a6xx: Add support for per-instance pagetables
drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 43 +++++ drivers/gpu/drm/msm/msm_drv.c | 15 +- drivers/gpu/drm/msm/msm_drv.h | 4 + drivers/gpu/drm/msm/msm_gem_vma.c | 9 + drivers/gpu/drm/msm/msm_gpu.c | 17 ++ drivers/gpu/drm/msm/msm_gpu.h | 5 + drivers/gpu/drm/msm/msm_gpummu.c | 2 +- drivers/gpu/drm/msm/msm_iommu.c | 180 +++++++++++++++++++- drivers/gpu/drm/msm/msm_mmu.h | 16 +- drivers/gpu/drm/msm/msm_ringbuffer.h | 1 + drivers/iommu/arm-smmu.c | 231 ++++++++++++++++++++++++-- drivers/iommu/arm-smmu.h | 1 + include/linux/io-pgtable.h | 11 +- include/linux/iommu.h | 1 + 14 files changed, 507 insertions(+), 29 deletions(-)