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| author | Rodrigo Vivi <rodrigo.vivi@intel.com> | 2023-12-15 18:45:48 +0300 |
|---|---|---|
| committer | Rodrigo Vivi <rodrigo.vivi@intel.com> | 2023-12-21 19:47:01 +0300 |
| commit | 535881a8c50b79085327e7dbe26a4c55f3e1591b (patch) | |
| tree | f1e9019c5ec063613c0910b0b9c7fdfc9011612b /drivers/gpu/drm/xe/xe_query.c | |
| parent | 4b437893a826b2f1d15f73e72506349656ea14b2 (diff) | |
| download | linux-535881a8c50b79085327e7dbe26a4c55f3e1591b.tar.xz | |
drm/xe/uapi: Document the memory_region bitmask
The uAPI should stay generic in regarding to the bitmask. It is
the userspace responsibility to check for the type/class of the
memory, without any assumption.
Also add comments inside the code to explain how it is actually
constructed so we don't accidentally change the assignment of
the instance and the masks.
No functional change in this patch. It only explains and document
the memory_region masks. A further follow-up work with the
organization of all memory regions around struct xe_mem_regions
is desired, but not part of this patch.
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: José Roberto de Souza <jose.souza@intel.com>
Acked-by: Mateusz Naklicki <mateusz.naklicki@intel.com>
Signed-off-by: Francois Dugast <francois.dugast@intel.com>
Diffstat (limited to 'drivers/gpu/drm/xe/xe_query.c')
| -rw-r--r-- | drivers/gpu/drm/xe/xe_query.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/gpu/drm/xe/xe_query.c b/drivers/gpu/drm/xe/xe_query.c index 56d61bf596b2..9b35673b286c 100644 --- a/drivers/gpu/drm/xe/xe_query.c +++ b/drivers/gpu/drm/xe/xe_query.c @@ -266,6 +266,11 @@ static int query_mem_regions(struct xe_device *xe, man = ttm_manager_type(&xe->ttm, XE_PL_TT); mem_regions->mem_regions[0].mem_class = DRM_XE_MEM_REGION_CLASS_SYSMEM; + /* + * The instance needs to be a unique number that represents the index + * in the placement mask used at xe_gem_create_ioctl() for the + * xe_bo_create() placement. + */ mem_regions->mem_regions[0].instance = 0; mem_regions->mem_regions[0].min_page_size = PAGE_SIZE; mem_regions->mem_regions[0].total_size = man->size << PAGE_SHIFT; @@ -381,6 +386,20 @@ static int query_gt_list(struct xe_device *xe, struct drm_xe_device_query *query gt_list->gt_list[id].tile_id = gt_to_tile(gt)->id; gt_list->gt_list[id].gt_id = gt->info.id; gt_list->gt_list[id].reference_clock = gt->info.reference_clock; + /* + * The mem_regions indexes in the mask below need to + * directly identify the struct + * drm_xe_query_mem_regions' instance constructed at + * query_mem_regions() + * + * For our current platforms: + * Bit 0 -> System Memory + * Bit 1 -> VRAM0 on Tile0 + * Bit 2 -> VRAM1 on Tile1 + * However the uAPI is generic and it's userspace's + * responsibility to check the mem_class, without any + * assumption. + */ if (!IS_DGFX(xe)) gt_list->gt_list[id].near_mem_regions = 0x1; else |