drm/amdgpu: fix TC cache flushing

TC_WB_ACTION must be set according to the docs

Signed-off-by: Marek Olšák <marek.olsak@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_drv.c

@@ -50,9 +50,11 @@
  * KMS wrapper.
  * - 3.0.0 - initial driver
  * - 3.1.0 - allow reading more status registers (GRBM, SRBM, SDMA, CP)
+ * - 3.2.0 - GFX8: Uses EOP_TC_WB_ACTION_EN, so UMDs don't have to do the same
+ *           at the end of IBs.
  */
 #define KMS_DRIVER_MAJOR	3
-#define KMS_DRIVER_MINOR	1
+#define KMS_DRIVER_MINOR	2
 #define KMS_DRIVER_PATCHLEVEL	0
 
 int amdgpu_vram_limit = 0;

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

@@ -5725,6 +5725,7 @@ static void gfx_v8_0_ring_emit_fence_gfx(struct amdgpu_ring *ring, u64 addr,
 	amdgpu_ring_write(ring, PACKET3(PACKET3_EVENT_WRITE_EOP, 4));
 	amdgpu_ring_write(ring, (EOP_TCL1_ACTION_EN |
 				 EOP_TC_ACTION_EN |
+				 EOP_TC_WB_ACTION_EN |
 				 EVENT_TYPE(CACHE_FLUSH_AND_INV_TS_EVENT) |
 				 EVENT_INDEX(5)));
 	amdgpu_ring_write(ring, addr & 0xfffffffc);