This series introduces a kernel-managed singleton BO representing the
MMIO-remap (HDP flush) page and exposes it to userspace through a new
GEM domain.
Design ------
- A tiny (1-page) TTM bucket is introduced for AMDGPU_PL_MMIO_REMAP
(mirroring doorbells).
- A singleton BO is created during amdgpu_ttm_init() and freed at
fini().
- The BO is kernel-owned and never evicted.
- amdgpu_gem_create_ioctl() recognizes the new GEM domain bit
(AMDGPU_GEM_DOMAIN_MMIO_REMAP) and returns a handle to the pre-created
singleton BO, enforcing size/alignment checks.
- Userspace thus gets a stable GEM handle and can mmap it to issue HDP
flushes.
* Only compilation tested so far (x86_64, defconfig + amdgpu enabled).
* No runtime validation yet.
Cc: Christian König <christian.koe...@amd.com>
Cc: Alex Deucher <alexander.deuc...@amd.com>
Srinivasan Shanmugam (7):
drm/amdgpu/uapi: add AMDGPU_GEM_DOMAIN_MMIO_REMAP
drm/amdgpu: Add New TTM Placement - AMDGPU_PL_MMIO_REMAP and wire up
plumbing
drm/amdgpu: Plumbing for MMIO_REMAP memtype and user-visible strings
drm/amdgpu: Add mmio_remap fields to amdgpu_device
drm/amdgpu: Implement TTM handling for MMIO_REMAP placement
drm/amdgpu: Create Singleton MMIO_REMAP BO and Initialize its pool
drm/amdgpu: Return Handle to MMIO_REMAP Singleton for GEM Create
drivers/gpu/drm/amd/amdgpu/amdgpu.h | 7 ++
drivers/gpu/drm/amd/amdgpu/amdgpu_fdinfo.c | 1 +
drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 56 +++++++++
drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 13 ++
drivers/gpu/drm/amd/amdgpu/amdgpu_object.h | 2 +
.../gpu/drm/amd/amdgpu/amdgpu_res_cursor.h | 2 +
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 112 +++++++++++++++++-
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h | 3 +-
include/drm/ttm/ttm_resource.h | 2 +-
include/uapi/drm/amdgpu_drm.h | 8 +-
10 files changed, 198 insertions(+), 8 deletions(-)
--
2.34.1
