drm/amdgpu: Modify the contiguous flags behaviour

Now we have two flags for contiguous VRAM buffer allocation.
If the application request for AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS,
it would set the ttm place TTM_PL_FLAG_CONTIGUOUS flag in the
buffer's placement function.

This patch will change the default behaviour of the two flags.

When we set AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS
- This means contiguous is not mandatory.
- we will try to allocate the contiguous buffer. Say if the
  allocation fails, we fallback to allocate the individual pages.

When we setTTM_PL_FLAG_CONTIGUOUS
- This means contiguous allocation is mandatory.
- we are setting this in amdgpu_bo_pin_restricted() before bo validation
  and check this flag in the vram manager file.
- if this is set, we should allocate the buffer pages contiguously.
  the allocation fails, we return -ENOSPC.

v2:
  - keep the mem_flags and bo->flags check as is(Christian)
  - place the TTM_PL_FLAG_CONTIGUOUS flag setting into the
    amdgpu_bo_pin_restricted function placement range iteration
    loop(Christian)
  - rename find_pages with amdgpu_vram_mgr_calculate_pages_per_block
    (Christian)
  - Keep the kernel BO allocation as is(Christain)
  - If BO pin vram allocation failed, we need to return -ENOSPC as
    RDMA cannot work with scattered VRAM pages(Philip)

v3(Christian):
  - keep contiguous flag handling outside of pages_per_block
    calculation
  - remove the hacky implementation in contiguous flag error
    handling code

v4(Christian):
  - use any variable and return value for non-contiguous
    fallback

v5: rebase to amd-staging-drm-next branch

Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Suggested-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
index 69513e34f97b..706345ea1430 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
@@ -153,8 +153,10 @@ void amdgpu_bo_placement_from_domain(struct amdgpu_bo *abo, u32 domain)
 		else
 			places[c].flags |= TTM_PL_FLAG_TOPDOWN;
 
-		if (flags & AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS)
+		if (abo->tbo.type == ttm_bo_type_kernel &&
+		    flags & AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS)
 			places[c].flags |= TTM_PL_FLAG_CONTIGUOUS;
+
 		c++;
 	}
 
@@ -967,6 +969,10 @@ int amdgpu_bo_pin_restricted(struct amdgpu_bo *bo, u32 domain,
 		if (!bo->placements[i].lpfn ||
 		    (lpfn && lpfn < bo->placements[i].lpfn))
 			bo->placements[i].lpfn = lpfn;
+
+		if (bo->flags & AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS &&
+		    bo->placements[i].mem_type == TTM_PL_VRAM)
+			bo->placements[i].flags |= TTM_PL_FLAG_CONTIGUOUS;
 	}
 
 	r = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);