[PATCH v7 1/6] drm: Add arch arm64 for drm_clflush_virt_range

[Michael Cheng]

Add arm64 support for drm_clflush_virt_range. dcache_clean_inval_poc
performs a flush by first performing a clean, follow by an invalidation
operation.

v2 (Michael Cheng): Use correct macro for cleaning and invalidation the
		    dcache.

Signed-off-by: Michael Cheng <michael.cheng at intel.com>
---
 drivers/gpu/drm/drm_cache.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c
index f19d9acbe959..94b3cc3fd482 100644
--- a/drivers/gpu/drm/drm_cache.c
+++ b/drivers/gpu/drm/drm_cache.c
@@ -39,6 +39,10 @@
 /* A small bounce buffer that fits on the stack. */
 #define MEMCPY_BOUNCE_SIZE 128
 
+#if defined(CONFIG_ARM64)
+#include <asm/cacheflush.h>
+#endif
+
 #if defined(CONFIG_X86)
 #include <asm/smp.h>
 
@@ -176,6 +180,10 @@ drm_clflush_virt_range(void *addr, unsigned long length)
 
 	if (wbinvd_on_all_cpus())
 		pr_err("Timed out waiting for cache flush\n");
+
+#elif defined(CONFIG_ARM64)
+	void *end = addr + length;
+	dcache_clean_inval_poc((unsigned long)addr, (unsigned long)end);
 #else
 	pr_err("Architecture has no drm_cache.c support\n");
 	WARN_ON_ONCE(1);
-- 
2.25.1