[3.11.y.z extended stable] Patch "arm64: Use Normal NonCacheable memory for writecombine" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    arm64: Use Normal NonCacheable memory for writecombine

to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 5559640cbfd1cf50984cd85753c97bebfa38ff8f Mon Sep 17 00:00:00 2001
From: Catalin Marinas <catalin.marinas at arm.com>
Date: Fri, 29 Nov 2013 10:56:14 +0000
Subject: arm64: Use Normal NonCacheable memory for writecombine

commit 4f00130b70e5eee813cc7bc298e0f3fdf79673cc upstream.

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 <catalin.marinas at arm.com>
Cc: Mark Brown <broonie at kernel.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 arch/arm64/include/asm/pgtable.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 0b27b65..bb969e9 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -255,7 +255,7 @@ 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
--
1.8.3.2