drm/amdgpu:use clear_ring to clr RB

In resume routine, we need clr RB prior to the
ring test of engine, otherwise some engine hang
duplicated during GPU reset.

Signed-off-by: Monk Liu <Monk.Liu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c

@@ -230,7 +230,7 @@ int amdgpu_ring_init(struct amdgpu_device *adev, struct amdgpu_ring *ring,
 			dev_err(adev->dev, "(%d) ring create failed\n", r);
 			return r;
 		}
-		memset((void *)ring->ring, 0, ring->ring_size);
+		amdgpu_ring_clear_ring(ring);
 	}
 	ring->ptr_mask = (ring->ring_size / 4) - 1;
 	ring->max_dw = max_dw;

drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c

@@ -4515,6 +4515,7 @@ static int gfx_v8_0_cp_gfx_resume(struct amdgpu_device *adev)
 	}
 
 	/* start the ring */
+	amdgpu_ring_clear_ring(ring);
 	gfx_v8_0_cp_gfx_start(adev);
 	ring->ready = true;
 	r = amdgpu_ring_test_ring(ring);

drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c

@@ -615,6 +615,7 @@ static int sdma_v3_0_gfx_resume(struct amdgpu_device *adev)
 
 	for (i = 0; i < adev->sdma.num_instances; i++) {
 		ring = &adev->sdma.instance[i].ring;
+		amdgpu_ring_clear_ring(ring);
 		wb_offset = (ring->rptr_offs * 4);
 
 		mutex_lock(&adev->srbm_mutex);