diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index bea11df..9979c43 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -462,3 +462,180 @@
 	*start = rsrc->start - offset;
 	*end = rsrc->end - offset;
 }
+
+/**
+ * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
+ * @hose: newly allocated pci_controller to be setup
+ * @dev: device node of the host bridge
+ * @primary: set if primary bus (32 bits only, soon to be deprecated)
+ *
+ * This function will parse the "ranges" property of a PCI host bridge device
+ * node and setup the resource mapping of a pci controller based on its
+ * content.
+ *
+ * Life would be boring if it wasn't for a few issues that we have to deal
+ * with here:
+ *
+ *   - We can only cope with one IO space range and up to 3 Memory space
+ *     ranges. However, some machines (thanks Apple !) tend to split their
+ *     space into lots of small contiguous ranges. So we have to coalesce.
+ *
+ *   - We can only cope with all memory ranges having the same offset
+ *     between CPU addresses and PCI addresses. Unfortunately, some bridges
+ *     are setup for a large 1:1 mapping along with a small "window" which
+ *     maps PCI address 0 to some arbitrary high address of the CPU space in
+ *     order to give access to the ISA memory hole.
+ *     The way out of here that I've chosen for now is to always set the
+ *     offset based on the first resource found, then override it if we
+ *     have a different offset and the previous was set by an ISA hole.
+ *
+ *   - Some busses have IO space not starting at 0, which causes trouble with
+ *     the way we do our IO resource renumbering. The code somewhat deals with
+ *     it for 64 bits but I would expect problems on 32 bits.
+ *
+ *   - Some 32 bits platforms such as 4xx can have physical space larger than
+ *     32 bits so we need to use 64 bits values for the parsing
+ */
+void __devinit pci_process_bridge_OF_ranges(struct pci_controller *hose,
+					    struct device_node *dev,
+					    int primary)
+{
+	const u32 *ranges;
+	int rlen;
+	int pna = of_n_addr_cells(dev);
+	int np = pna + 5;
+	int memno = 0, isa_hole = -1;
+	u32 pci_space;
+	unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
+	unsigned long long isa_mb = 0;
+	struct resource *res;
+
+	printk(KERN_INFO "PCI host bridge %s %s ranges:\n",
+	       dev->full_name, primary ? "(primary)" : "");
+
+	/* Get ranges property */
+	ranges = of_get_property(dev, "ranges", &rlen);
+	if (ranges == NULL)
+		return;
+
+	/* Parse it */
+	while ((rlen -= np * 4) >= 0) {
+		/* Read next ranges element */
+		pci_space = ranges[0];
+		pci_addr = of_read_number(ranges + 1, 2);
+		cpu_addr = of_translate_address(dev, ranges + 3);
+		size = of_read_number(ranges + pna + 3, 2);
+		ranges += np;
+		if (cpu_addr == OF_BAD_ADDR || size == 0)
+			continue;
+
+		/* Now consume following elements while they are contiguous */
+		for (; rlen >= np * sizeof(u32);
+		     ranges += np, rlen -= np * 4) {
+			if (ranges[0] != pci_space)
+				break;
+			pci_next = of_read_number(ranges + 1, 2);
+			cpu_next = of_translate_address(dev, ranges + 3);
+			if (pci_next != pci_addr + size ||
+			    cpu_next != cpu_addr + size)
+				break;
+			size += of_read_number(ranges + pna + 3, 2);
+		}
+
+		/* Act based on address space type */
+		res = NULL;
+		switch ((pci_space >> 24) & 0x3) {
+		case 1:		/* PCI IO space */
+			printk(KERN_INFO
+			       "  IO 0x%016llx..0x%016llx -> 0x%016llx\n",
+			       cpu_addr, cpu_addr + size - 1, pci_addr);
+
+			/* We support only one IO range */
+			if (hose->pci_io_size) {
+				printk(KERN_INFO
+				       " \\--> Skipped (too many) !\n");
+				continue;
+			}
+#ifdef CONFIG_PPC32
+			/* On 32 bits, limit I/O space to 16MB */
+			if (size > 0x01000000)
+				size = 0x01000000;
+
+			/* 32 bits needs to map IOs here */
+			hose->io_base_virt = ioremap(cpu_addr, size);
+
+			/* Expect trouble if pci_addr is not 0 */
+			if (primary)
+				isa_io_base =
+					(unsigned long)hose->io_base_virt;
+#endif /* CONFIG_PPC32 */
+			/* pci_io_size and io_base_phys always represent IO
+			 * space starting at 0 so we factor in pci_addr
+			 */
+			hose->pci_io_size = pci_addr + size;
+			hose->io_base_phys = cpu_addr - pci_addr;
+
+			/* Build resource */
+			res = &hose->io_resource;
+			res->flags = IORESOURCE_IO;
+			res->start = pci_addr;
+			break;
+		case 2:		/* PCI Memory space */
+			printk(KERN_INFO
+			       " MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
+			       cpu_addr, cpu_addr + size - 1, pci_addr,
+			       (pci_space & 0x40000000) ? "Prefetch" : "");
+
+			/* We support only 3 memory ranges */
+			if (memno >= 3) {
+				printk(KERN_INFO
+				       " \\--> Skipped (too many) !\n");
+				continue;
+			}
+			/* Handles ISA memory hole space here */
+			if (pci_addr == 0) {
+				isa_mb = cpu_addr;
+				isa_hole = memno;
+				if (primary || isa_mem_base == 0)
+					isa_mem_base = cpu_addr;
+			}
+
+			/* We get the PCI/Mem offset from the first range or
+			 * the, current one if the offset came from an ISA
+			 * hole. If they don't match, bugger.
+			 */
+			if (memno == 0 ||
+			    (isa_hole >= 0 && pci_addr != 0 &&
+			     hose->pci_mem_offset == isa_mb))
+				hose->pci_mem_offset = cpu_addr - pci_addr;
+			else if (pci_addr != 0 &&
+				 hose->pci_mem_offset != cpu_addr - pci_addr) {
+				printk(KERN_INFO
+				       " \\--> Skipped (offset mismatch) !\n");
+				continue;
+			}
+
+			/* Build resource */
+			res = &hose->mem_resources[memno++];
+			res->flags = IORESOURCE_MEM;
+			if (pci_space & 0x40000000)
+				res->flags |= IORESOURCE_PREFETCH;
+			res->start = cpu_addr;
+			break;
+		}
+		if (res != NULL) {
+			res->name = dev->full_name;
+			res->end = res->start + size - 1;
+			res->parent = NULL;
+			res->sibling = NULL;
+			res->child = NULL;
+		}
+	}
+
+	/* Out of paranoia, let's put the ISA hole last if any */
+	if (isa_hole >= 0 && memno > 0 && isa_hole != (memno-1)) {
+		struct resource tmp = hose->mem_resources[isa_hole];
+		hose->mem_resources[isa_hole] = hose->mem_resources[memno-1];
+		hose->mem_resources[memno-1] = tmp;
+	}
+}