arm64: Use Normal NonCacheable memory for writecombine

This provides better performance compared to Device GRE and also allows unaligned accesses. Such memory is intended to be used with standard RAM (e.g. framebuffers) and not I/O. Signed-off-by: Catalin Marinas <[email protected]>
kyagi · Nov 29, 2013 · 4f00130 · 4f00130
1 parent 2dacab7
commit 4f00130
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
@@ -254,7 +254,7 @@ static inline int has_transparent_hugepage(void)
 #define pgprot_noncached(prot) \
 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE))
 #define pgprot_writecombine(prot) \
-	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_GRE))
+	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC))
 #define pgprot_dmacoherent(prot) \
 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC))
 #define __HAVE_PHYS_MEM_ACCESS_PROT