drm/amd/amdgpu: Enable clockgating in UVD6 for Stoney

This patch enables clockgating for the UVD6 block in Stoney.
Signed-off-by: NTom St Denis <tom.stdenis@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

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

@@ -1086,11 +1086,15 @@ static int vi_common_early_init(void *handle)
 		adev->external_rev_id = adev->rev_id + 0x14;
 		break;
 	case CHIP_CARRIZO:
-	case CHIP_STONEY:
 		adev->cg_flags = 0;
 		adev->pg_flags = 0;
 		adev->external_rev_id = adev->rev_id + 0x1;
 		break;
+	case CHIP_STONEY:
+		adev->cg_flags = AMD_CG_SUPPORT_UVD_MGCG;
+		adev->pg_flags = 0;
+		adev->external_rev_id = adev->rev_id + 0x1;
+		break;
 	default:
 		/* FIXME: not supported yet */
 		return -EINVAL;