The armada_gem driver stores a DMA address token in a resource_size_t.
This is safe because both are always at least 32 bits wide and can store
any address that is accessible by this driver.

However, it is a slight type mismatch when we assign it from/to
an sg_dma_address() value, and we get a warning in any configuration
in which resource_size_t is shorter than dma_addr_t:

drivers/gpu/drm/armada/armada_gem.c: In function 
'armada_gem_alloc_private_object':
arch/arm/include/asm/dma-mapping.h:16:24: warning: large integer implicitly 
truncated to unsigned type [-Woverflow]
 #define DMA_ERROR_CODE (~(dma_addr_t)0x0)
                        ^
drivers/gpu/drm/armada/armada_gem.c:204:18: note: in expansion of macro 
'DMA_ERROR_CODE'
  obj->dev_addr = DMA_ERROR_CODE;
                  ^

Changing the type to dma_addr_t solves both issues.

Signed-off-by: Arnd Bergmann <arnd at arndb.de>
---
 drivers/gpu/drm/armada/armada_gem.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/armada/armada_gem.h 
b/drivers/gpu/drm/armada/armada_gem.h
index b000ea3a829a..270cff02c1cd 100644
--- a/drivers/gpu/drm/armada/armada_gem.h
+++ b/drivers/gpu/drm/armada/armada_gem.h
@@ -15,7 +15,7 @@ struct armada_gem_object {
        struct drm_gem_object   obj;
        void                    *addr;
        phys_addr_t             phys_addr;
-       resource_size_t         dev_addr;
+       dma_addr_t              dev_addr;
        struct drm_mm_node      *linear;        /* for linear backed */
        struct page             *page;          /* for page backed */
        struct sg_table         *sgt;           /* for imported */
-- 
2.7.0

Reply via email to