--- /dev/null
+++ b/arch/powerpc/sysdev/rb_iomap.c
@@ -0,0 +1,223 @@
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/mm.h>
+#include <asm/io.h>
+
+#define LOCALBUS_START		0x40000000
+#define LOCALBUS_MASK		0x007fffff
+#define LOCALBUS_REGMASK	0x001fffff
+
+static void __iomem *localbus_base;
+
+static inline int is_localbus(void __iomem *addr)
+{
+	return ((unsigned) addr & ~LOCALBUS_MASK) == LOCALBUS_START;
+}
+
+static inline unsigned localbus_regoff(unsigned reg) {
+	return (reg << 16) | (((reg ^ 8) & 8) << 17);
+}
+
+static inline void __iomem *localbus_addr(void __iomem *addr)
+{
+	return localbus_base
+	    + ((unsigned) addr & LOCALBUS_MASK & ~LOCALBUS_REGMASK)
+	    + localbus_regoff((unsigned) addr & LOCALBUS_REGMASK);
+}
+
+unsigned int ioread8(void __iomem *addr)
+{
+	if (is_localbus(addr))
+		return in_be16(localbus_addr(addr)) >> 8;
+	return readb(addr);
+}
+EXPORT_SYMBOL(ioread8);
+
+unsigned int ioread16(void __iomem *addr)
+{
+	if (is_localbus(addr))
+		return le16_to_cpu(in_be16(localbus_addr(addr)));
+	return readw(addr);
+}
+EXPORT_SYMBOL(ioread16);
+
+unsigned int ioread16be(void __iomem *addr)
+{
+	return in_be16(addr);
+}
+EXPORT_SYMBOL(ioread16be);
+
+unsigned int ioread32(void __iomem *addr)
+{
+	return readl(addr);
+}
+EXPORT_SYMBOL(ioread32);
+
+unsigned int ioread32be(void __iomem *addr)
+{
+	return in_be32(addr);
+}
+EXPORT_SYMBOL(ioread32be);
+
+void iowrite8(u8 val, void __iomem *addr)
+{
+	if (is_localbus(addr))
+		out_be16(localbus_addr(addr), ((u16) val) << 8);
+	else
+		writeb(val, addr);
+}
+EXPORT_SYMBOL(iowrite8);
+
+void iowrite16(u16 val, void __iomem *addr)
+{
+	if (is_localbus(addr))
+		out_be16(localbus_addr(addr), cpu_to_le16(val));
+	else
+		writew(val, addr);
+}
+EXPORT_SYMBOL(iowrite16);
+
+void iowrite16be(u16 val, void __iomem *addr)
+{
+	out_be16(addr, val);
+}
+EXPORT_SYMBOL(iowrite16be);
+
+void iowrite32(u32 val, void __iomem *addr)
+{
+	writel(val, addr);
+}
+EXPORT_SYMBOL(iowrite32);
+
+void iowrite32be(u32 val, void __iomem *addr)
+{
+	out_be32(addr, val);
+}
+EXPORT_SYMBOL(iowrite32be);
+
+void ioread8_rep(void __iomem *addr, void *dst, unsigned long count)
+{
+	if (is_localbus(addr)) {
+		unsigned i;
+		void *laddr = localbus_addr(addr);
+		u8 *buf = dst;
+
+		for (i = 0; i < count; ++i) {
+			*buf++ = in_be16(laddr) >> 8;
+		}
+	} else {
+		_insb((u8 __iomem *) addr, dst, count);
+	}
+}
+EXPORT_SYMBOL(ioread8_rep);
+
+void ioread16_rep(void __iomem *addr, void *dst, unsigned long count)
+{
+	if (is_localbus(addr)) {
+		unsigned i;
+		void *laddr = localbus_addr(addr);
+		u16 *buf = dst;
+
+		for (i = 0; i < count; ++i) {
+			*buf++ = in_be16(laddr);
+		}
+	} else {
+		_insw_ns((u16 __iomem *) addr, dst, count);
+	}
+}
+EXPORT_SYMBOL(ioread16_rep);
+
+void ioread32_rep(void __iomem *addr, void *dst, unsigned long count)
+{
+	_insl_ns((u32 __iomem *) addr, dst, count);
+}
+EXPORT_SYMBOL(ioread32_rep);
+
+void iowrite8_rep(void __iomem *addr, const void *src, unsigned long count)
+{
+	if (is_localbus(addr)) {
+		unsigned i;
+		void *laddr = localbus_addr(addr);
+		const u8 *buf = src;
+
+		for (i = 0; i < count; ++i) {
+			out_be16(laddr, ((u16) *buf++) << 8);
+		}
+	} else {
+		_outsb((u8 __iomem *) addr, src, count);
+	}
+}
+EXPORT_SYMBOL(iowrite8_rep);
+
+void iowrite16_rep(void __iomem *addr, const void *src, unsigned long count)
+{
+	if (is_localbus(addr)) {
+		unsigned i;
+		void *laddr = localbus_addr(addr);
+		const u16 *buf = src;
+
+		for (i = 0; i < count; ++i) {
+			out_be16(laddr, *buf++);
+		}
+	} else {
+		_outsw_ns((u16 __iomem *) addr, src, count);
+	}
+}
+EXPORT_SYMBOL(iowrite16_rep);
+
+void iowrite32_rep(void __iomem *addr, const void *src, unsigned long count)
+{
+	_outsl_ns((u32 __iomem *) addr, src, count);
+}
+EXPORT_SYMBOL(iowrite32_rep);
+
+void __iomem *ioport_map(unsigned long port, unsigned int len)
+{
+	return (void __iomem *) (port + _IO_BASE);
+}
+EXPORT_SYMBOL(ioport_unmap);
+
+void ioport_unmap(void __iomem *addr)
+{
+	/* Nothing to do */
+}
+EXPORT_SYMBOL(ioport_map);
+
+void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max)
+{
+	unsigned long start = pci_resource_start(dev, bar);
+	unsigned long len = pci_resource_len(dev, bar);
+	unsigned long flags = pci_resource_flags(dev, bar);
+
+	if (!len)
+		return NULL;
+	if (max && len > max)
+		len = max;
+	if (flags & IORESOURCE_IO)
+		return ioport_map(start, len);
+	if (flags & IORESOURCE_MEM)
+		return ioremap(start, len);
+	/* What? */
+	return NULL;
+}
+EXPORT_SYMBOL(pci_iomap);
+
+void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
+{
+	/* Nothing to do */
+}
+EXPORT_SYMBOL(pci_iounmap);
+
+void __iomem *localbus_map(unsigned long addr, unsigned int len)
+{
+	if (!localbus_base)
+		localbus_base = ioremap(addr & ~LOCALBUS_MASK,
+					LOCALBUS_MASK + 1);
+	return (void *) (LOCALBUS_START + (addr & LOCALBUS_MASK));
+}
+EXPORT_SYMBOL(localbus_map);
+
+void localbus_unmap(void __iomem *addr)
+{
+}
+EXPORT_SYMBOL(localbus_unmap);