[U-Boot] [PATCH] ARM1136: Align stack to 8 bytes

[Vitaly Kuzmichev]

The ARM ABI requires that the stack be aligned to 8 bytes as it is noted
in Procedure Call Standard for the ARM Architecture:
http://infocenter.arm.com/help/topic/com.arm.doc.ihi0042d/index.html

Unaligned SP also causes the problem with variable-length arrays
allocation when VLA address becomes less than stack pointer during
aligning of this address, so the further 'push' into the stack
overwrites first 4 bytes of VLA.

Signed-off-by: Vitaly Kuzmichev <vkuzmichev at mvista.com>
Signed-off-by: George G. Davis <gdavis at mvista.com>
---
 arch/arm/cpu/arm1136/start.S |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/arm/cpu/arm1136/start.S b/arch/arm/cpu/arm1136/start.S
index 957f438..d0c5717 100644
--- a/arch/arm/cpu/arm1136/start.S
+++ b/arch/arm/cpu/arm1136/start.S
@@ -185,6 +185,7 @@ stack_setup:
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
 #endif	/* CONFIG_PRELOADER */
+	bic	sp, sp, #7		/* 8-byte alignment                 */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment	    */
-- 
1.6.2.3.127.gb136