diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 352879c1b86b7a852ced703413c71b88989fbc03..bae53831c06bfd1572615fda0dfe80de2a25be1c 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -826,11 +826,15 @@ config MAPLE
 config PCI
 	bool "PCI support"
 	depends on SYS_SUPPORTS_PCI
+	select PCI_DOMAINS
 	help
 	  Find out whether you have a PCI motherboard. PCI is the name of a
 	  bus system, i.e. the way the CPU talks to the other stuff inside
 	  your box. If you have PCI, say Y, otherwise N.
 
+config PCI_DOMAINS
+	bool
+
 source "drivers/pci/pcie/Kconfig"
 
 source "drivers/pci/Kconfig"
diff --git a/arch/sh/drivers/pci/pci.c b/arch/sh/drivers/pci/pci.c
index 82e59bc6210e0e842722ccd828f75f04efe7e04e..45a15cab01df0b0d92225a33c0424b7b90960c8b 100644
--- a/arch/sh/drivers/pci/pci.c
+++ b/arch/sh/drivers/pci/pci.c
@@ -33,15 +33,22 @@ static int pci_initialized;
 static void __devinit pcibios_scanbus(struct pci_channel *hose)
 {
 	static int next_busno;
+	static int need_domain_info;
 	struct pci_bus *bus;
 
 	bus = pci_scan_bus(next_busno, hose->pci_ops, hose);
+	hose->bus = bus;
+
+	need_domain_info = need_domain_info || hose->index;
+	hose->need_domain_info = need_domain_info;
 	if (bus) {
 		next_busno = bus->subordinate + 1;
 		/* Don't allow 8-bit bus number overflow inside the hose -
 		   reserve some space for bridges. */
-		if (next_busno > 224)
+		if (next_busno > 224) {
 			next_busno = 0;
+			need_domain_info = 1;
+		}
 
 		pci_bus_size_bridges(bus);
 		pci_bus_assign_resources(bus);
@@ -307,9 +314,15 @@ static void __iomem *ioport_map_pci(struct pci_dev *dev,
 {
 	struct pci_channel *chan = dev->sysdata;
 
-	if (!chan->io_map_base)
+	if (unlikely(!chan->io_map_base)) {
 		chan->io_map_base = generic_io_base;
 
+		if (pci_domains_supported)
+			panic("To avoid data corruption io_map_base MUST be "
+			      "set with multiple PCI domains.");
+	}
+
+
 	return (void __iomem *)(chan->io_map_base + port);
 }
 
diff --git a/arch/sh/include/asm/pci.h b/arch/sh/include/asm/pci.h
index f362d8a045e7b735ea31ace874b8f7ee18e148c2..d124a009889f670cd6d2c2e50373e6e092ef7bf2 100644
--- a/arch/sh/include/asm/pci.h
+++ b/arch/sh/include/asm/pci.h
@@ -15,6 +15,7 @@
  */
 struct pci_channel {
 	struct pci_channel	*next;
+	struct pci_bus		*bus;
 
 	struct pci_ops		*pci_ops;
 	struct resource		*io_resource;
@@ -24,8 +25,10 @@ struct pci_channel {
 	unsigned long		mem_offset;
 
 	unsigned long		reg_base;
-
 	unsigned long		io_map_base;
+
+	unsigned int		index;
+	unsigned int		need_domain_info;
 };
 
 extern void register_pci_controller(struct pci_channel *hose);
@@ -108,6 +111,14 @@ extern void pcibios_resource_to_bus(struct pci_dev *dev,
 extern void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
 				    struct pci_bus_region *region);
 
+#define pci_domain_nr(bus) ((struct pci_channel *)(bus)->sysdata)->index
+
+static inline int pci_proc_domain(struct pci_bus *bus)
+{
+	struct pci_channel *hose = bus->sysdata;
+	return hose->need_domain_info;
+}
+
 /* Chances are this interrupt is wired PC-style ...  */
 static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel)
 {