[PATCH 2/2] drm/amdgpu: expose AMDGPU_GEM_CREATE_VRAM_CLEARED to user space

[Flora Cui]

Change-Id: I256178afa18c1a433fe60d8656d1c5cc5d55cf2f
Signed-off-by: Flora Cui <Flora.Cui at amd.com>
Reviewed-by: Chunming Zhou <David1.Zhou at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 23 +++++++++++++++++++++++
 include/uapi/drm/amdgpu_drm.h              |  2 ++
 2 files changed, 25 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
index 6f0873c..974fd26 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
@@ -281,6 +281,29 @@ int amdgpu_bo_create_restricted(struct amdgpu_device *adev,
 
 	trace_amdgpu_bo_create(bo);
 
+	if (flags & AMDGPU_GEM_CREATE_VRAM_CLEARED &&
+	    bo->tbo.mem.placement & TTM_PL_FLAG_VRAM) {
+		struct fence *fence;
+
+		/* make sure module init routine finishes since it requires gpu_scheduler */
+		if (!adev->accel_working) {
+			DRM_INFO("amdgpu: acceleration disabled, skipping clear op\n");
+			return 0;
+		}
+
+		r = amdgpu_bo_reserve(bo, false);
+		if (unlikely(r != 0)) {
+			DRM_INFO("amdgpu: reserve bo fail, skipping clear op\n");
+			return 0;
+		}
+		amdgpu_fill_buffer(bo, 0, bo->tbo.resv, &fence);
+		amdgpu_bo_fence(bo, fence, false);
+		amdgpu_bo_unreserve(bo);
+		fence_put(bo->tbo.moving);
+		bo->tbo.moving = fence_get(fence);
+		fence_put(fence);
+	}
+
 	return 0;
 }
 
diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
index 946f238..8df3816 100644
--- a/include/uapi/drm/amdgpu_drm.h
+++ b/include/uapi/drm/amdgpu_drm.h
@@ -75,6 +75,8 @@
 #define AMDGPU_GEM_CREATE_NO_CPU_ACCESS		(1 << 1)
 /* Flag that USWC attributes should be used for GTT */
 #define AMDGPU_GEM_CREATE_CPU_GTT_USWC		(1 << 2)
+/* Flag that the memory should be in VRAM and cleared */
+#define AMDGPU_GEM_CREATE_VRAM_CLEARED		(1 << 3)
 
 struct drm_amdgpu_gem_create_in  {
 	/** the requested memory size */
-- 
1.9.1