drm/amdgpu: enable BUS master after pci reset

Re-enable bus mastering after GPU reset. We disable it
at the top of these functions, so balance them by
re-enabling it.

Signed-off-by: Chunming Zhou <David1.Zhou@amd.com>
eviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -1179,6 +1179,8 @@ static int cik_gpu_pci_config_reset(struct amdgpu_device *adev)
 	/* wait for asic to come out of reset */
 	for (i = 0; i < adev->usec_timeout; i++) {
 		if (RREG32(mmCONFIG_MEMSIZE) != 0xffffffff) {
+			/* enable BM */
+			pci_set_master(adev->pdev);
 			r = 0;
 			break;
 		}

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

@@ -612,8 +612,11 @@ static int vi_gpu_pci_config_reset(struct amdgpu_device *adev)
 
 	/* wait for asic to come out of reset */
 	for (i = 0; i < adev->usec_timeout; i++) {
-		if (RREG32(mmCONFIG_MEMSIZE) != 0xffffffff)
+		if (RREG32(mmCONFIG_MEMSIZE) != 0xffffffff) {
+			/* enable BM */
+			pci_set_master(adev->pdev);
 			return 0;
+		}
 		udelay(1);
 	}
 	return -EINVAL;