+static int pci_register_host_bridge(struct pci_host_bridge *bridge)
+{
+ struct device *parent = bridge->dev.parent;
+ struct resource_entry *window, *n;
+ struct pci_bus *bus, *b;
+ resource_size_t offset;
+ LIST_HEAD(resources);
+ struct resource *res;
+ char addr[64], *fmt;
+ const char *name;
+ int err;
+
+ bus = pci_alloc_bus(NULL);
+ if (!bus)
+ return -ENOMEM;
+
+ bridge->bus = bus;
+
+ /* temporarily move resources off the list */
+ list_splice_init(&bridge->windows, &resources);
+ bus->sysdata = bridge->sysdata;
+ bus->msi = bridge->msi;
+ bus->ops = bridge->ops;
+ bus->number = bus->busn_res.start = bridge->busnr;
+#ifdef CONFIG_PCI_DOMAINS_GENERIC
+ bus->domain_nr = pci_bus_find_domain_nr(bus, parent);
+#endif
+
+ b = pci_find_bus(pci_domain_nr(bus), bridge->busnr);
+ if (b) {
+ /* If we already got to this bus through a different bridge, ignore it */
+ dev_dbg(&b->dev, "bus already known\n");
+ err = -EEXIST;
+ goto free;
+ }
+
+ dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(bus),
+ bridge->busnr);
+
+ err = pcibios_root_bridge_prepare(bridge);
+ if (err)
+ goto free;
+
+ err = device_register(&bridge->dev);
+ if (err)
+ put_device(&bridge->dev);
+
+ bus->bridge = get_device(&bridge->dev);
+ device_enable_async_suspend(bus->bridge);
+ pci_set_bus_of_node(bus);
+ pci_set_bus_msi_domain(bus);
+
+ if (!parent)
+ set_dev_node(bus->bridge, pcibus_to_node(bus));
+
+ bus->dev.class = &pcibus_class;
+ bus->dev.parent = bus->bridge;
+
+ dev_set_name(&bus->dev, "%04x:%02x", pci_domain_nr(bus), bus->number);
+ name = dev_name(&bus->dev);
+
+ err = device_register(&bus->dev);
+ if (err)
+ goto unregister;
+
+ pcibios_add_bus(bus);
+
+ /* Create legacy_io and legacy_mem files for this bus */
+ pci_create_legacy_files(bus);
+
+ if (parent)
+ dev_info(parent, "PCI host bridge to bus %s\n", name);
+ else
+ pr_info("PCI host bridge to bus %s\n", name);
+
+ /* Add initial resources to the bus */
+ resource_list_for_each_entry_safe(window, n, &resources) {
+ list_move_tail(&window->node, &bridge->windows);
+ offset = window->offset;
+ res = window->res;
+
+ if (res->flags & IORESOURCE_BUS)
+ pci_bus_insert_busn_res(bus, bus->number, res->end);
+ else
+ pci_bus_add_resource(bus, res, 0);
+
+ if (offset) {
+ if (resource_type(res) == IORESOURCE_IO)
+ fmt = " (bus address [%#06llx-%#06llx])";
+ else
+ fmt = " (bus address [%#010llx-%#010llx])";
+
+ snprintf(addr, sizeof(addr), fmt,
+ (unsigned long long)(res->start - offset),
+ (unsigned long long)(res->end - offset));
+ } else
+ addr[0] = '\0';
+
+ dev_info(&bus->dev, "root bus resource %pR%s\n", res, addr);
+ }
+
+ down_write(&pci_bus_sem);
+ list_add_tail(&bus->node, &pci_root_buses);
+ up_write(&pci_bus_sem);
+
+ return 0;
+
+unregister:
+ put_device(&bridge->dev);
+ device_unregister(&bridge->dev);
+
+free:
+ kfree(bus);
+ return err;
+}
+