[PATCH v2 0/2] Default to cachable mappings for GEM SHMEM

[Thomas Zimmermann]

Shmem-allocated memory uses the system's default caching flags,
usually involving cached mappings.

By default, SHMEM GEM helpers map pages using writecombine. Only a few
drivers require this setting. Others revert it to default mappings
flags. Some could benefit from caching, but don't care.

Unify the behaviour by switching the SHMEM GEM code to use cached
mappings (i.e., PAGE_KERNEL actually); just like regular shmem memory
does. The 3 drivers that require write combining explicitly select it
during GEM object creation.

The exception is dma-buf imported pages, which are always mapped
using writecombine mode.

v2:
	* recreate patches on top of latest SHMEM helpers
	* update lima, panfrost, v3d (Daniel, Rob)
	* udl has been updated before separately.

Thomas Zimmermann (2):
  drm/shmem-helper: Use cached mappings by default
  drm/shmem-helper: Removed drm_gem_shmem_create_object_cached()

 drivers/gpu/drm/drm_gem_shmem_helper.c  | 37 ++++---------------------
 drivers/gpu/drm/lima/lima_gem.c         |  2 +-
 drivers/gpu/drm/mgag200/mgag200_drv.c   |  1 -
 drivers/gpu/drm/panfrost/panfrost_gem.c |  2 +-
 drivers/gpu/drm/udl/udl_drv.c           |  2 --
 drivers/gpu/drm/v3d/v3d_bo.c            |  2 +-
 drivers/gpu/drm/virtio/virtgpu_object.c |  1 -
 drivers/gpu/drm/vkms/vkms_drv.c         |  1 -
 include/drm/drm_gem_shmem_helper.h      |  7 ++---
 9 files changed, 11 insertions(+), 44 deletions(-)

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2.29.0