[v2,0/6] iommu-arm-smmu: Add auxiliary domains and per-instance pagetables

Message

Jordan Crouse June 26, 2020, 8:04 p.m. UTC

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(-)