ARM: 5995/1: ARM: Add L2x0 outer_sync() support (3/4)

The L2x0 cache controllers need to explicitly drain their write buffer
even for Normal Noncacheable memory accesses.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
index 0733463..21ad68b 100644
--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c
@@ -93,6 +93,15 @@
 }
 #endif
 
+static void l2x0_cache_sync(void)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&l2x0_lock, flags);
+	cache_sync();
+	spin_unlock_irqrestore(&l2x0_lock, flags);
+}
+
 static inline void l2x0_inv_all(void)
 {
 	unsigned long flags;
@@ -225,6 +234,7 @@
 	outer_cache.inv_range = l2x0_inv_range;
 	outer_cache.clean_range = l2x0_clean_range;
 	outer_cache.flush_range = l2x0_flush_range;
+	outer_cache.sync = l2x0_cache_sync;
 
 	printk(KERN_INFO "L2X0 cache controller enabled\n");
 }