[PATCHv5 0/6] System Cache support for GPU and required SMMU support

Sai Prakash Ranjan
2020-09-22T06:18:39Z

Some hardware variants contain a system cache or the last level
cache(llc). This cache is typically a large block which is shared
by multiple clients on the SOC. GPU uses the system cache to cache
both the GPU data buffers(like textures) as well the SMMU pagetables.
This helps with improved render performance as well as lower power
consumption by reducing the bus traffic to the system memory.

The system cache architecture allows the cache to be split into slices
which then be used by multiple SOC clients. This patch series is an
effort to enable and use two of those slices perallocated for the GPU,
one for the GPU data buffers and another for the GPU SMMU hardware
pagetables.

Patch 1 - Patch 4 adds system cache support in SMMU and GPU driver.
Patch 5 and 6 are minor cleanups for arm-smmu impl.

The series is based on top of https://gitlab.freedesktop.org/drm/msm/-/tree/msm-next-pgtables

Changes in v5:
* Drop cleanup of blank lines since it was intentional (Robin)
* Rebase again on top of msm-next-pgtables as it moves pretty fast

Changes in v4:
* Drop IOMMU_SYS_CACHE prot flag
* Rebase on top of https://gitlab.freedesktop.org/drm/msm/-/tree/msm-next-pgtables

Changes in v3:
* Fix domain attribute setting to before iommu_attach_device()
* Fix few code style and checkpatch warnings
* Rebase on top of Jordan's latest split pagetables and per-instance
pagetables support

Changes in v2:
* Addressed review comments and rebased on top of Jordan's split
pagetables series

Sai Prakash Ranjan (4):
iommu/io-pgtable-arm: Add support to use system cache
iommu/arm-smmu: Add domain attribute for system cache
iommu: arm-smmu-impl: Use table to list QCOM implementations
iommu: arm-smmu-impl: Add a space before open parenthesis

Sharat Masetty (2):
drm/msm: rearrange the gpu_rmw() function
drm/msm/a6xx: Add support for using system cache(LLC)

drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 83 ++++++++++++++++++++++
drivers/gpu/drm/msm/adreno/a6xx_gpu.h | 4 ++
drivers/gpu/drm/msm/adreno/adreno_gpu.c | 17 +++++
drivers/gpu/drm/msm/msm_drv.c | 8 +++
drivers/gpu/drm/msm/msm_drv.h | 1 +
drivers/gpu/drm/msm/msm_gpu.h | 5 +-
drivers/iommu/arm/arm-smmu/arm-smmu-impl.c | 14 ++--
drivers/iommu/arm/arm-smmu/arm-smmu.c | 17 +++++
drivers/iommu/arm/arm-smmu/arm-smmu.h | 1 +
drivers/iommu/io-pgtable-arm.c | 7 +-
include/linux/io-pgtable.h | 4 ++
include/linux/iommu.h | 1 +
12 files changed, 152 insertions(+), 10 deletions(-)

base-commit: 115b1aca7a2a9c0649b1f5f6cffee6873c7efd89