diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h
index af074923d598..4cc420cfaa78 100644
--- a/arch/powerpc/include/asm/io.h
+++ b/arch/powerpc/include/asm/io.h
@@ -788,8 +788,10 @@ extern void __iounmap_at(void *ea, unsigned long size);
 
 #define mmio_read16be(addr)		readw_be(addr)
 #define mmio_read32be(addr)		readl_be(addr)
+#define mmio_read64be(addr)		readq_be(addr)
 #define mmio_write16be(val, addr)	writew_be(val, addr)
 #define mmio_write32be(val, addr)	writel_be(val, addr)
+#define mmio_write64be(val, addr)	writeq_be(val, addr)
 #define mmio_insb(addr, dst, count)	readsb(addr, dst, count)
 #define mmio_insw(addr, dst, count)	readsw(addr, dst, count)
 #define mmio_insl(addr, dst, count)	readsl(addr, dst, count)
diff --git a/include/asm-generic/iomap.h b/include/asm-generic/iomap.h
index 5b63b94ef6b5..5a4af0199b32 100644
--- a/include/asm-generic/iomap.h
+++ b/include/asm-generic/iomap.h
@@ -31,9 +31,16 @@ extern unsigned int ioread16(void __iomem *);
 extern unsigned int ioread16be(void __iomem *);
 extern unsigned int ioread32(void __iomem *);
 extern unsigned int ioread32be(void __iomem *);
-#ifdef CONFIG_64BIT
-extern u64 ioread64(void __iomem *);
-extern u64 ioread64be(void __iomem *);
+
+#ifdef readq
+#define ioread64_lo_hi ioread64_lo_hi
+#define ioread64_hi_lo ioread64_hi_lo
+#define ioread64be_lo_hi ioread64be_lo_hi
+#define ioread64be_hi_lo ioread64be_hi_lo
+extern u64 ioread64_lo_hi(void __iomem *addr);
+extern u64 ioread64_hi_lo(void __iomem *addr);
+extern u64 ioread64be_lo_hi(void __iomem *addr);
+extern u64 ioread64be_hi_lo(void __iomem *addr);
 #endif
 
 extern void iowrite8(u8, void __iomem *);
@@ -41,9 +48,16 @@ extern void iowrite16(u16, void __iomem *);
 extern void iowrite16be(u16, void __iomem *);
 extern void iowrite32(u32, void __iomem *);
 extern void iowrite32be(u32, void __iomem *);
-#ifdef CONFIG_64BIT
-extern void iowrite64(u64, void __iomem *);
-extern void iowrite64be(u64, void __iomem *);
+
+#ifdef writeq
+#define iowrite64_lo_hi iowrite64_lo_hi
+#define iowrite64_hi_lo iowrite64_hi_lo
+#define iowrite64be_lo_hi iowrite64be_lo_hi
+#define iowrite64be_hi_lo iowrite64be_hi_lo
+extern void iowrite64_lo_hi(u64 val, void __iomem *addr);
+extern void iowrite64_hi_lo(u64 val, void __iomem *addr);
+extern void iowrite64be_lo_hi(u64 val, void __iomem *addr);
+extern void iowrite64be_hi_lo(u64 val, void __iomem *addr);
 #endif
 
 /*
diff --git a/lib/iomap.c b/lib/iomap.c
index a05d9fa21794..75bb8c9e0980 100644
--- a/lib/iomap.c
+++ b/lib/iomap.c
@@ -67,6 +67,7 @@ static void bad_io_access(unsigned long port, const char *access)
 #ifndef mmio_read16be
 #define mmio_read16be(addr) be16_to_cpu((__be16 __force)__raw_readw(addr))
 #define mmio_read32be(addr) be32_to_cpu((__be32 __force)__raw_readl(addr))
+#define mmio_read64be(addr) be64_to_cpu((__be64 __force)__raw_readq(addr))
 #endif
 
 unsigned int ioread8(void __iomem *addr)
@@ -100,6 +101,80 @@ EXPORT_SYMBOL(ioread16be);
 EXPORT_SYMBOL(ioread32);
 EXPORT_SYMBOL(ioread32be);
 
+#ifdef readq
+static u64 pio_read64_lo_hi(unsigned long port)
+{
+	u64 lo, hi;
+
+	lo = inl(port);
+	hi = inl(port + sizeof(u32));
+
+	return lo | (hi << 32);
+}
+
+static u64 pio_read64_hi_lo(unsigned long port)
+{
+	u64 lo, hi;
+
+	hi = inl(port + sizeof(u32));
+	lo = inl(port);
+
+	return lo | (hi << 32);
+}
+
+static u64 pio_read64be_lo_hi(unsigned long port)
+{
+	u64 lo, hi;
+
+	lo = pio_read32be(port + sizeof(u32));
+	hi = pio_read32be(port);
+
+	return lo | (hi << 32);
+}
+
+static u64 pio_read64be_hi_lo(unsigned long port)
+{
+	u64 lo, hi;
+
+	hi = pio_read32be(port);
+	lo = pio_read32be(port + sizeof(u32));
+
+	return lo | (hi << 32);
+}
+
+u64 ioread64_lo_hi(void __iomem *addr)
+{
+	IO_COND(addr, return pio_read64_lo_hi(port), return readq(addr));
+	return 0xffffffffffffffffULL;
+}
+
+u64 ioread64_hi_lo(void __iomem *addr)
+{
+	IO_COND(addr, return pio_read64_hi_lo(port), return readq(addr));
+	return 0xffffffffffffffffULL;
+}
+
+u64 ioread64be_lo_hi(void __iomem *addr)
+{
+	IO_COND(addr, return pio_read64be_lo_hi(port),
+		return mmio_read64be(addr));
+	return 0xffffffffffffffffULL;
+}
+
+u64 ioread64be_hi_lo(void __iomem *addr)
+{
+	IO_COND(addr, return pio_read64be_hi_lo(port),
+		return mmio_read64be(addr));
+	return 0xffffffffffffffffULL;
+}
+
+EXPORT_SYMBOL(ioread64_lo_hi);
+EXPORT_SYMBOL(ioread64_hi_lo);
+EXPORT_SYMBOL(ioread64be_lo_hi);
+EXPORT_SYMBOL(ioread64be_hi_lo);
+
+#endif /* readq */
+
 #ifndef pio_write16be
 #define pio_write16be(val,port) outw(swab16(val),port)
 #define pio_write32be(val,port) outl(swab32(val),port)
@@ -110,6 +185,8 @@ EXPORT_SYMBOL(ioread32be);
 	__raw_writew((u16 __force)cpu_to_be16(val), port)
 #define mmio_write32be(val, port) \
 	__raw_writel((u32 __force)cpu_to_be32(val), port)
+#define mmio_write64be(val, port) \
+	__raw_writeq((u64 __force)cpu_to_be64(val), port)
 #endif
 
 void iowrite8(u8 val, void __iomem *addr)
@@ -138,6 +215,62 @@ EXPORT_SYMBOL(iowrite16be);
 EXPORT_SYMBOL(iowrite32);
 EXPORT_SYMBOL(iowrite32be);
 
+#ifdef writeq
+static void pio_write64_lo_hi(u64 val, unsigned long port)
+{
+	outl(val, port);
+	outl(val >> 32, port + sizeof(u32));
+}
+
+static void pio_write64_hi_lo(u64 val, unsigned long port)
+{
+	outl(val >> 32, port + sizeof(u32));
+	outl(val, port);
+}
+
+static void pio_write64be_lo_hi(u64 val, unsigned long port)
+{
+	pio_write32be(val, port + sizeof(u32));
+	pio_write32be(val >> 32, port);
+}
+
+static void pio_write64be_hi_lo(u64 val, unsigned long port)
+{
+	pio_write32be(val >> 32, port);
+	pio_write32be(val, port + sizeof(u32));
+}
+
+void iowrite64_lo_hi(u64 val, void __iomem *addr)
+{
+	IO_COND(addr, pio_write64_lo_hi(val, port),
+		writeq(val, addr));
+}
+
+void iowrite64_hi_lo(u64 val, void __iomem *addr)
+{
+	IO_COND(addr, pio_write64_hi_lo(val, port),
+		writeq(val, addr));
+}
+
+void iowrite64be_lo_hi(u64 val, void __iomem *addr)
+{
+	IO_COND(addr, pio_write64be_lo_hi(val, port),
+		mmio_write64be(val, addr));
+}
+
+void iowrite64be_hi_lo(u64 val, void __iomem *addr)
+{
+	IO_COND(addr, pio_write64be_hi_lo(val, port),
+		mmio_write64be(val, addr));
+}
+
+EXPORT_SYMBOL(iowrite64_lo_hi);
+EXPORT_SYMBOL(iowrite64_hi_lo);
+EXPORT_SYMBOL(iowrite64be_lo_hi);
+EXPORT_SYMBOL(iowrite64be_hi_lo);
+
+#endif /* readq */
+
 /*
  * These are the "repeat MMIO read/write" functions.
  * Note the "__raw" accesses, since we don't want to
