drm: add helper to check for wc memory support

commit 4b0e4e4af6c6dc8354dcb72182d52c1bc55f12fc upstream.

Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/drm/drm_cache.h b/include/drm/drm_cache.h
index 7bfb063029d83fe1374e78a174f4a638bc39bc49..461a0558bca4d8d16e81b88e0286e3fa6251ab79 100644 (file)
--- a/include/drm/drm_cache.h
+++ b/include/drm/drm_cache.h
@@ -35,4 +35,13 @@
 
 void drm_clflush_pages(struct page *pages[], unsigned long num_pages);
 
+static inline bool drm_arch_can_wc_memory(void)
+{
+#if defined(CONFIG_PPC) && !defined(CONFIG_NOT_COHERENT_CACHE)
+       return false;
+#else
+       return true;
+#endif
+}
+
 #endif