diff --git a/arch/ppc/include/asm/io.h b/arch/ppc/include/asm/io.h
index 0052989..d3473e5 100644
--- a/arch/ppc/include/asm/io.h
+++ b/arch/ppc/include/asm/io.h
@@ -135,73 +135,76 @@
 /*
  * 8, 16 and 32 bit, big and little endian I/O operations, with barrier.
  */
-extern inline int in_8(volatile u8 *addr)
+extern inline u8 in_8(const volatile u8 __iomem *addr)
 {
-    int ret;
+	u8 ret;
 
-    __asm__ __volatile__("lbz%U1%X1 %0,%1; eieio" : "=r" (ret) : "m" (*addr));
-    return ret;
+	__asm__ __volatile__("sync; lbz%U1%X1 %0,%1; twi 0,%0,0; isync"
+			: "=r" (ret) : "m" (*addr));
+	return ret;
 }
 
-extern inline void out_8(volatile u8 *addr, int val)
+extern inline void out_8(volatile u8 __iomem *addr, u8 val)
 {
-    __asm__ __volatile__("stb%U0%X0 %1,%0; eieio" : "=m" (*addr) : "r" (val));
+	__asm__ __volatile__("sync;stb%U0%X0 %1,%0" : "=m" (*addr) : "r" (val));
 }
 
-extern inline int in_le16(volatile u16 *addr)
+extern inline u16 in_le16(const volatile u16 __iomem *addr)
 {
-    int ret;
+	u16 ret;
 
-    __asm__ __volatile__("lhbrx %0,0,%1; eieio" : "=r" (ret) :
-		  "r" (addr), "m" (*addr));
-    return ret;
+	__asm__ __volatile__("sync; lhbrx %0,0,%1; twi 0,%0,0; isync"
+			: "=r" (ret) : "r" (addr), "m" (*addr));
+	return ret;
 }
 
-extern inline int in_be16(volatile u16 *addr)
+extern inline u16 in_be16(const volatile u16 __iomem *addr)
 {
-    int ret;
+	u16 ret;
 
-    __asm__ __volatile__("lhz%U1%X1 %0,%1; eieio" : "=r" (ret) : "m" (*addr));
-    return ret;
+	__asm__ __volatile__("sync; lhz%U1%X1 %0,%1; twi 0,%0,0; isync"
+			: "=r" (ret) : "m" (*addr));
+	return ret;
 }
 
-extern inline void out_le16(volatile u16 *addr, int val)
+extern inline void out_le16(volatile u16 __iomem *addr, u16 val)
 {
-    __asm__ __volatile__("sthbrx %1,0,%2; eieio" : "=m" (*addr) :
-		  "r" (val), "r" (addr));
+	__asm__ __volatile__("sync; sthbrx %1,0,%2"
+			: "=m" (*addr) : "r" (val), "r" (addr));
 }
 
-extern inline void out_be16(volatile u16 *addr, int val)
+extern inline void out_be16(volatile u16 __iomem *addr, u16 val)
 {
-    __asm__ __volatile__("sth%U0%X0 %1,%0; eieio" : "=m" (*addr) : "r" (val));
+	__asm__ __volatile__("sync;sth%U0%X0 %1,%0" : "=m" (*addr) : "r" (val));
 }
 
-extern inline unsigned in_le32(volatile u32 *addr)
+extern inline u32 in_le32(const volatile u32 __iomem *addr)
 {
-    unsigned ret;
+	u32 ret;
 
-    __asm__ __volatile__("lwbrx %0,0,%1; eieio" : "=r" (ret) :
-		 "r" (addr), "m" (*addr));
-    return ret;
+	__asm__ __volatile__("sync; lwbrx %0,0,%1; twi 0,%0,0; isync"
+			: "=r" (ret) : "r" (addr), "m" (*addr));
+	return ret;
 }
 
-extern inline unsigned in_be32(volatile u32 *addr)
+extern inline u32 in_be32(const volatile u32 __iomem *addr)
 {
-    unsigned ret;
+	u32 ret;
 
-    __asm__ __volatile__("lwz%U1%X1 %0,%1; eieio" : "=r" (ret) : "m" (*addr));
-    return ret;
+	__asm__ __volatile__("sync; lwz%U1%X1 %0,%1; twi 0,%0,0; isync"
+			: "=r" (ret) : "m" (*addr));
+	return ret;
 }
 
-extern inline void out_le32(volatile unsigned *addr, int val)
+extern inline void out_le32(volatile u32 __iomem *addr, u32 val)
 {
-    __asm__ __volatile__("stwbrx %1,0,%2; eieio" : "=m" (*addr) :
-		 "r" (val), "r" (addr));
+	__asm__ __volatile__("sync; stwbrx %1,0,%2"
+			: "=m" (*addr) : "r" (val), "r" (addr));
 }
 
-extern inline void out_be32(volatile unsigned *addr, int val)
+extern inline void out_be32(volatile u32 __iomem *addr, u32 val)
 {
-    __asm__ __volatile__("stw%U0%X0 %1,%0; eieio" : "=m" (*addr) : "r" (val));
+	__asm__ __volatile__("sync;stw%U0%X0 %1,%0" : "=m" (*addr) : "r" (val));
 }
 
 /*