drm/radeon/kms: fix cayman acceleration

The TCC disable setup was incorrect.  This
prevents the GPU from hanging when draw commands
are issued.

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/ni.c b/drivers/gpu/drm/radeon/ni.c
index e9e45ea..3d8a763 100644
--- a/drivers/gpu/drm/radeon/ni.c
+++ b/drivers/gpu/drm/radeon/ni.c
@@ -674,7 +674,7 @@
 
 	cc_rb_backend_disable = RREG32(CC_RB_BACKEND_DISABLE);
 	cc_gc_shader_pipe_config = RREG32(CC_GC_SHADER_PIPE_CONFIG);
-	cgts_tcc_disable = RREG32(CGTS_TCC_DISABLE);
+	cgts_tcc_disable = 0xff000000;
 	gc_user_rb_backend_disable = RREG32(GC_USER_RB_BACKEND_DISABLE);
 	gc_user_shader_pipe_config = RREG32(GC_USER_SHADER_PIPE_CONFIG);
 	cgts_user_tcc_disable = RREG32(CGTS_USER_TCC_DISABLE);