diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 393706a5261b0..850d7bf0c873f 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -652,6 +652,210 @@ static void acpi_pci_root_remove(struct acpi_device *device)
kfree(root);
}
+/*
+ * Following code to support acpi_pci_root_create() is copied from
+ * arch/x86/pci/acpi.c and modified so it could be reused by x86, IA64
+ * and ARM64.
+ */
+static void acpi_pci_root_validate_resources(struct device *dev,
+ struct list_head *resources,
+ unsigned long type)
+{
+ LIST_HEAD(list);
+ struct resource *res1, *res2, *root = NULL;
+ struct resource_entry *tmp, *entry, *entry2;
+
+ BUG_ON((type & (IORESOURCE_MEM | IORESOURCE_IO)) == 0);
+ root = (type & IORESOURCE_MEM) ? &iomem_resource : &ioport_resource;
+
+ list_splice_init(resources, &list);
+ resource_list_for_each_entry_safe(entry, tmp, &list) {
+ bool free = false;
+ resource_size_t end;
+
+ res1 = entry->res;
+ if (!(res1->flags & type))
+ goto next;
+
+ /* Exclude non-addressable range or non-addressable portion */
+ end = min(res1->end, root->end);
+ if (end <= res1->start) {
+ dev_info(dev, "host bridge window %pR (ignored, not CPU addressable)\n",
+ res1);
+ free = true;
+ goto next;
+ } else if (res1->end != end) {
+ dev_info(dev, "host bridge window %pR ([%#llx-%#llx] ignored, not CPU addressable)\n",
+ res1, (unsigned long long)end + 1,
+ (unsigned long long)res1->end);
+ res1->end = end;
+ }
+
+ resource_list_for_each_entry(entry2, resources) {
+ res2 = entry2->res;
+ if (!(res2->flags & type))
+ continue;
+
+ /*
+ * I don't like throwing away windows because then
+ * our resources no longer match the ACPI _CRS, but
+ * the kernel resource tree doesn't allow overlaps.
+ */
+ if (resource_overlaps(res1, res2)) {
+ res2->start = min(res1->start, res2->start);
+ res2->end = max(res1->end, res2->end);
+ dev_info(dev, "host bridge window expanded to %pR; %pR ignored\n",
+ res2, res1);
+ free = true;
+ goto next;
+ }
+ }
+
+next:
+ resource_list_del(entry);
+ if (free)
+ resource_list_free_entry(entry);
+ else
+ resource_list_add_tail(entry, resources);
+ }
+}
+
+int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
+{
+ int ret;
+ struct list_head *list = &info->resources;
+ struct acpi_device *device = info->bridge;
+ struct resource_entry *entry, *tmp;
+ unsigned long flags;
+
+ flags = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_MEM_8AND16BIT;
+ ret = acpi_dev_get_resources(device, list,
+ acpi_dev_filter_resource_type_cb,
+ (void *)flags);
+ if (ret < 0)
+ dev_warn(&device->dev,
+ "failed to parse _CRS method, error code %d\n", ret);
+ else if (ret == 0)
+ dev_dbg(&device->dev,
+ "no IO and memory resources present in _CRS\n");
+ else {
+ resource_list_for_each_entry_safe(entry, tmp, list) {
+ if (entry->res->flags & IORESOURCE_DISABLED)
+ resource_list_destroy_entry(entry);
+ else
+ entry->res->name = info->name;
+ }
+ acpi_pci_root_validate_resources(&device->dev, list,
+ IORESOURCE_MEM);
+ acpi_pci_root_validate_resources(&device->dev, list,
+ IORESOURCE_IO);
+ }
+
+ return ret;
+}
+
+static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
+{
+ struct resource_entry *entry, *tmp;
+ struct resource *res, *conflict, *root = NULL;
+
+ resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
+ res = entry->res;
+ if (res->flags & IORESOURCE_MEM)
+ root = &iomem_resource;
+ else if (res->flags & IORESOURCE_IO)
+ root = &ioport_resource;
+ else
+ continue;
+
+ conflict = insert_resource_conflict(root, res);
+ if (conflict) {
+ dev_info(&info->bridge->dev,
+ "ignoring host bridge window %pR (conflicts with %s %pR)\n",
+ res, conflict->name, conflict);
+ resource_list_destroy_entry(entry);
+ }
+ }
+}
+
+static void __acpi_pci_root_release_info(struct acpi_pci_root_info *info)
+{
+ struct resource *res;
+ struct resource_entry *entry, *tmp;
+
+ if (!info)
+ return;
+
+ resource_list_for_each_entry_safe(entry, tmp, &info->resources) {
+ res = entry->res;
+ if (res->parent &&
+ (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
+ release_resource(res);
+ resource_list_destroy_entry(entry);
+ }
+
+ info->ops->release_info(info);
+}
+
+static void acpi_pci_root_release_info(struct pci_host_bridge *bridge)
+{
+ struct resource *res;
+ struct resource_entry *entry;
+
+ resource_list_for_each_entry(entry, &bridge->windows) {
+ res = entry->res;
+ if (res->parent &&
+ (res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
+ release_resource(res);
+ }
+ __acpi_pci_root_release_info(bridge->release_data);
+}
+
+struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
+ struct acpi_pci_root_ops *ops,
+ struct acpi_pci_root_info *info,
+ void *sysdata)
+{
+ int ret, busnum = root->secondary.start;
+ struct acpi_device *device = root->device;
+ int node = acpi_get_node(device->handle);
+ struct pci_bus *bus;
+
+ info->root = root;
+ info->bridge = device;
+ info->ops = ops;
+ INIT_LIST_HEAD(&info->resources);
+ snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x",
+ root->segment, busnum);
+
+ if (ops->init_info && ops->init_info(info))
+ goto out_release_info;
+ if (ops->prepare_resources)
+ ret = ops->prepare_resources(info);
+ else
+ ret = acpi_pci_probe_root_resources(info);
+ if (ret < 0)
+ goto out_release_info;
+
+ pci_acpi_root_add_resources(info);
+ pci_add_resource(&info->resources, &root->secondary);
+ bus = pci_create_root_bus(NULL, busnum, ops->pci_ops,
+ sysdata, &info->resources);
+ if (!bus)
+ goto out_release_info;
+
+ pci_scan_child_bus(bus);
+ pci_set_host_bridge_release(to_pci_host_bridge(bus->bridge),
+ acpi_pci_root_release_info, info);
+ if (node != NUMA_NO_NODE)
+ dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
+ return bus;
+
+out_release_info:
+ __acpi_pci_root_release_info(info);
+ return NULL;
+}
+
void __init acpi_pci_root_init(void)
{
acpi_hest_init();
diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
index a965efa52152e..89ab0572dbc63 100644
--- a/include/linux/pci-acpi.h
+++ b/include/linux/pci-acpi.h
@@ -52,6 +52,30 @@ static inline acpi_handle acpi_pci_get_bridge_handle(struct pci_bus *pbus)
return ACPI_HANDLE(dev);
}
+struct acpi_pci_root;
+struct acpi_pci_root_ops;
+
+struct acpi_pci_root_info {
+ struct acpi_pci_root *root;
+ struct acpi_device *bridge;
+ struct acpi_pci_root_ops *ops;
+ struct list_head resources;
+ char name[16];
+};
+
+struct acpi_pci_root_ops {
+ struct pci_ops *pci_ops;
+ int (*init_info)(struct acpi_pci_root_info *info);
+ void (*release_info)(struct acpi_pci_root_info *info);
+ int (*prepare_resources)(struct acpi_pci_root_info *info);
+};
+
+extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info);
+extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
+ struct acpi_pci_root_ops *ops,
+ struct acpi_pci_root_info *info,
+ void *sd);
+
void acpi_pci_add_bus(struct pci_bus *bus);
void acpi_pci_remove_bus(struct pci_bus *bus);