drm/omap: fix TILER on OMAP5

On OMAP5 it is not possible to use TILER buffer with CPU when caching or
write-combining is used. Doing so leads to errors from the memory
manager.

However, on OMAP4, write-combining works fine.

This patch adds platform specific data for the TILER, and a function
tiler_get_cpu_cache_flags() which can be used to get the caching mode to
be used.

Note that without write-combining the use of the TILER buffer with CPU
is unusably slow. It's still good to have it operational for testing
purposes.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/gpu/drm/omapdrm/omap_dmm_tiler.h b/drivers/gpu/drm/omapdrm/omap_dmm_tiler.h
index 4fdd61e54bd2..e83c78372db8 100644
--- a/drivers/gpu/drm/omapdrm/omap_dmm_tiler.h
+++ b/drivers/gpu/drm/omapdrm/omap_dmm_tiler.h
@@ -106,6 +106,7 @@ uint32_t tiler_stride(enum tiler_fmt fmt, uint32_t orient);
 size_t tiler_size(enum tiler_fmt fmt, uint16_t w, uint16_t h);
 size_t tiler_vsize(enum tiler_fmt fmt, uint16_t w, uint16_t h);
 void tiler_align(enum tiler_fmt fmt, uint16_t *w, uint16_t *h);
+uint32_t tiler_get_cpu_cache_flags(void);
 bool dmm_is_available(void);
 
 extern struct platform_driver omap_dmm_driver;