ARM: add soc memory barrier extension

Add an extension to the heavy barrier code to allow a SoC specific
memory barrier function to be provided.  This is needed for platforms
where the interconnect has weak ordering, and thus needs assistance
to ensure that memory writes are properly visible in the correct order
to other parts of the system.

Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Richard Woodruff <r-woodruff2@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/include/asm/barrier.h b/arch/arm/include/asm/barrier.h
index fea99b0e20878f6170e239aa31c7b3a692d3f5a5..3d8f1d3ad9a76e62f3c3e6ae0e3ba35b4500bfcf 100644 (file)
--- a/arch/arm/include/asm/barrier.h
+++ b/arch/arm/include/asm/barrier.h
@@ -37,6 +37,7 @@
 #endif
 
 #ifdef CONFIG_ARM_HEAVY_MB
+extern void (*soc_mb)(void);
 extern void arm_heavy_mb(void);
 #define __arm_heavy_mb(x...) do { dsb(x); arm_heavy_mb(); } while (0)
 #else

diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index ce6c2960d5ace171a56149988deb38b1139dabdc..1ec8e7590fc6823bf1d1ffe87c1901f645ffcd07 100644 (file)
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -22,12 +22,16 @@
 #include "mm.h"
 
 #ifdef CONFIG_ARM_HEAVY_MB
+void (*soc_mb)(void);
+
 void arm_heavy_mb(void)
 {
 #ifdef CONFIG_OUTER_CACHE_SYNC
        if (outer_cache.sync)
                outer_cache.sync();
 #endif
+       if (soc_mb)
+               soc_mb();
 }
 EXPORT_SYMBOL(arm_heavy_mb);
 #endif