[PATCH v3] drm/amdgpu: refine amdgpu_bo_create_kernel_at()

[Lang Yu]

Use amdgpu_bo_create_reserved() to create a BO in VRAM
domain would fail if requested VRAM size is large(>128MB)
on APU which usually has a default 512MB VRAM.

That's because VRAM is framgented after several allocations.

The approach is using amdgpu_bo_create_reserved() to
create a BO in CPU domain first, it will always succeed.

v2: Don't overwrite the contents at specific offset.
v3: Don't return GPU addr.

Signed-off-by: Lang Yu <Lang.Yu at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
index ff73cc11d47e..df5ba9509a41 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
@@ -377,27 +377,36 @@ int amdgpu_bo_create_kernel_at(struct amdgpu_device *adev,
 	size = ALIGN(size, PAGE_SIZE);
 
 	r = amdgpu_bo_create_reserved(adev, size, PAGE_SIZE,
-				      AMDGPU_GEM_DOMAIN_VRAM, bo_ptr, NULL,
-				      cpu_addr);
+				      AMDGPU_GEM_DOMAIN_CPU,
+				      bo_ptr, NULL, NULL);
 	if (r)
 		return r;
 
 	if ((*bo_ptr) == NULL)
 		return 0;
 
+	(*bo_ptr)->preferred_domains = AMDGPU_GEM_DOMAIN_VRAM;
+	(*bo_ptr)->allowed_domains = (*bo_ptr)->preferred_domains;
+	(*bo_ptr)->flags = AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS;
+	(*bo_ptr)->flags |= cpu_addr ? AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED
+		: AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
+
 	/*
 	 * Remove the original mem node and create a new one at the request
 	 * position.
 	 */
-	if (cpu_addr)
-		amdgpu_bo_kunmap(*bo_ptr);
-
 	ttm_resource_free(&(*bo_ptr)->tbo, &(*bo_ptr)->tbo.resource);
 
 	for (i = 0; i < (*bo_ptr)->placement.num_placement; ++i) {
 		(*bo_ptr)->placements[i].fpfn = offset >> PAGE_SHIFT;
 		(*bo_ptr)->placements[i].lpfn = (offset + size) >> PAGE_SHIFT;
+		(*bo_ptr)->placements[i].mem_type = TTM_PL_VRAM;
+		(*bo_ptr)->placements[i].flags = TTM_PL_FLAG_CONTIGUOUS;
+
+		if (!((*bo_ptr)->flags & AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED))
+			(*bo_ptr)->placements[i].flags |= TTM_PL_FLAG_TOPDOWN;
 	}
+
 	r = ttm_bo_mem_space(&(*bo_ptr)->tbo, &(*bo_ptr)->placement,
 			     &(*bo_ptr)->tbo.resource, &ctx);
 	if (r)
-- 
2.25.1