diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index 9db072d..3c91e7c 100644
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -26,6 +26,7 @@
 #include <linux/types.h>
 #include <asm/byteorder.h>
 #include <asm/memory.h>
+#include <asm/system.h>
 
 /*
  * ISA I/O bus memory addresses are 1:1 with the physical address.
@@ -191,6 +192,15 @@
 #define writel_relaxed(v,c)	((void)__raw_writel((__force u32) \
 					cpu_to_le32(v),__mem_pci(c)))
 
+#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
+#define readb(c)		({ u8  __v = readb_relaxed(c); rmb(); __v; })
+#define readw(c)		({ u16 __v = readw_relaxed(c); rmb(); __v; })
+#define readl(c)		({ u32 __v = readl_relaxed(c); rmb(); __v; })
+
+#define writeb(v,c)		({ wmb(); writeb_relaxed(v,c); })
+#define writew(v,c)		({ wmb(); writew_relaxed(v,c); })
+#define writel(v,c)		({ wmb(); writel_relaxed(v,c); })
+#else
 #define readb(c)		readb_relaxed(c)
 #define readw(c)		readw_relaxed(c)
 #define readl(c)		readl_relaxed(c)
@@ -198,6 +208,7 @@
 #define writeb(v,c)		writeb_relaxed(v,c)
 #define writew(v,c)		writew_relaxed(v,c)
 #define writel(v,c)		writel_relaxed(v,c)
+#endif
 
 #define readsb(p,d,l)		__raw_readsb(__mem_pci(p),d,l)
 #define readsw(p,d,l)		__raw_readsw(__mem_pci(p),d,l)