[PATCH] ARM: set SCTRL[A] only when architecture does not support unaligned access

[PATCH] ARM: set SCTRL[A] only when architecture does not support unaligned access

[Enrico Scholz]

Recent gcc generates code with unaligned access when architecture
supports it. Setting A bit unconditionally causes data-aborts on such
code rendering barebox unusable.

Signed-off-by: Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
---
 arch/arm/cpu/start.c |   11 ++++++++++-
 1 files changed, 10 insertions(+), 1 deletions(-)

diff --git a/arch/arm/cpu/start.c b/arch/arm/cpu/start.c
index 5e09300..ff68783 100644
--- a/arch/arm/cpu/start.c
+++ b/arch/arm/cpu/start.c
@@ -84,7 +84,16 @@ void __naked __bare_init reset(void)
 	/* disable MMU stuff and caches */
 	r = get_cr();
 	r &= ~(CR_M | CR_C | CR_B | CR_S | CR_R | CR_V);
-	r |= CR_A | CR_I;
+	r |= CR_I;
+
+	if (!(r & CR_U))
+		/* catch unaligned access on architectures which do not
+		 * support unaligned access */
+		r |= CR_A;
+	else
+		r &= ~CR_A;
+
+
 #ifdef __ARMEB__
 	r |= CR_B;
 #endif
-- 
1.7.7.4


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