PCI changes for the v3.9 merge window:

Host bridge hotplug
     - Major overhaul of ACPI host bridge add/start (Rafael Wysocki, Yinghai Lu)
     - Major overhaul of PCI/ACPI binding (Rafael Wysocki, Yinghai Lu)
     - Split out ACPI host bridge and ACPI PCI device hotplug (Yinghai Lu)
     - Stop caching _PRT and make independent of bus numbers (Yinghai Lu)
 
   PCI device hotplug
     - Clean up cpqphp dead code (Sasha Levin)
     - Disable ARI unless device and upstream bridge support it (Yijing Wang)
     - Initialize all hot-added devices (not functions 0-7) (Yijing Wang)
 
   Power management
     - Don't touch ASPM if disabled (Joe Lawrence)
     - Fix ASPM link state management (Myron Stowe)
 
   Miscellaneous
     - Fix PCI_EXP_FLAGS accessor (Alex Williamson)
     - Disable Bus Master in pci_device_shutdown (Konstantin Khlebnikov)
     - Document hotplug resource and MPS parameters (Yijing Wang)
     - Add accessor for PCIe capabilities (Myron Stowe)
     - Drop pciehp suspend/resume messages (Paul Bolle)
     - Make pci_slot built-in only (not a module) (Jiang Liu)
     - Remove unused PCI/ACPI bind ops (Jiang Liu)
     - Removed used pci_root_bus (Bjorn Helgaas)
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Merge tag 'pci-v3.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI changes from Bjorn Helgaas:
 "Host bridge hotplug
    - Major overhaul of ACPI host bridge add/start (Rafael Wysocki, Yinghai Lu)
    - Major overhaul of PCI/ACPI binding (Rafael Wysocki, Yinghai Lu)
    - Split out ACPI host bridge and ACPI PCI device hotplug (Yinghai Lu)
    - Stop caching _PRT and make independent of bus numbers (Yinghai Lu)

  PCI device hotplug
    - Clean up cpqphp dead code (Sasha Levin)
    - Disable ARI unless device and upstream bridge support it (Yijing Wang)
    - Initialize all hot-added devices (not functions 0-7) (Yijing Wang)

  Power management
    - Don't touch ASPM if disabled (Joe Lawrence)
    - Fix ASPM link state management (Myron Stowe)

  Miscellaneous
    - Fix PCI_EXP_FLAGS accessor (Alex Williamson)
    - Disable Bus Master in pci_device_shutdown (Konstantin Khlebnikov)
    - Document hotplug resource and MPS parameters (Yijing Wang)
    - Add accessor for PCIe capabilities (Myron Stowe)
    - Drop pciehp suspend/resume messages (Paul Bolle)
    - Make pci_slot built-in only (not a module) (Jiang Liu)
    - Remove unused PCI/ACPI bind ops (Jiang Liu)
    - Removed used pci_root_bus (Bjorn Helgaas)"

* tag 'pci-v3.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (51 commits)
  PCI/ACPI: Don't cache _PRT, and don't associate them with bus numbers
  PCI: Fix PCI Express Capability accessors for PCI_EXP_FLAGS
  ACPI / PCI: Make pci_slot built-in only, not a module
  PCI/PM: Clear state_saved during suspend
  PCI: Use atomic_inc_return() rather than atomic_add_return()
  PCI: Catch attempts to disable already-disabled devices
  PCI: Disable Bus Master unconditionally in pci_device_shutdown()
  PCI: acpiphp: Remove dead code for PCI host bridge hotplug
  PCI: acpiphp: Create companion ACPI devices before creating PCI devices
  PCI: Remove unused "rc" in virtfn_add_bus()
  PCI: pciehp: Drop suspend/resume ENTRY messages
  PCI/ASPM: Don't touch ASPM if forcibly disabled
  PCI/ASPM: Deallocate upstream link state even if device is not PCIe
  PCI: Document MPS parameters pci=pcie_bus_safe, pci=pcie_bus_perf, etc
  PCI: Document hpiosize= and hpmemsize= resource reservation parameters
  PCI: Use PCI Express Capability accessor
  PCI: Introduce accessor to retrieve PCIe Capabilities Register
  PCI: Put pci_dev in device tree as early as possible
  PCI: Skip attaching driver in device_add()
  PCI: acpiphp: Keep driver loaded even if no slots found
  ...

drivers/acpi/Kconfig

@@ -306,7 +306,7 @@ config ACPI_DEBUG_FUNC_TRACE
 	  is about half of the penalty and is rarely useful.
 
 config ACPI_PCI_SLOT
-	tristate "PCI slot detection driver"
+	bool "PCI slot detection driver"
 	depends on SYSFS
 	default n
 	help
@@ -315,9 +315,6 @@ config ACPI_PCI_SLOT
 	  i.e., segment/bus/device/function tuples, with physical slots in
 	  the system.  If you are unsure, say N.
 
-	  To compile this driver as a module, choose M here:
-	  the module will be called pci_slot.
-
 config X86_PM_TIMER
 	bool "Power Management Timer Support" if EXPERT
 	depends on X86

drivers/acpi/internal.h

@@ -25,8 +25,14 @@
 
 int init_acpi_device_notify(void);
 int acpi_scan_init(void);
+#ifdef	CONFIG_ACPI_PCI_SLOT
+void acpi_pci_slot_init(void);
+#else
+static inline void acpi_pci_slot_init(void) { }
+#endif
 void acpi_pci_root_init(void);
 void acpi_pci_link_init(void);
+void acpi_pci_root_hp_init(void);
 void acpi_platform_init(void);
 int acpi_sysfs_init(void);
 void acpi_csrt_init(void);

drivers/acpi/osl.c

@@ -84,8 +84,7 @@ static acpi_osd_handler acpi_irq_handler;
 static void *acpi_irq_context;
 static struct workqueue_struct *kacpid_wq;
 static struct workqueue_struct *kacpi_notify_wq;
-struct workqueue_struct *kacpi_hotplug_wq;
-EXPORT_SYMBOL(kacpi_hotplug_wq);
+static struct workqueue_struct *kacpi_hotplug_wq;
 
 /*
  * This list of permanent mappings is for memory that may be accessed from
@@ -1778,3 +1777,24 @@ void acpi_os_set_prepare_sleep(int (*func)(u8 sleep_state,
 {
 	__acpi_os_prepare_sleep = func;
 }
+
+void alloc_acpi_hp_work(acpi_handle handle, u32 type, void *context,
+			void (*func)(struct work_struct *work))
+{
+	struct acpi_hp_work *hp_work;
+	int ret;
+
+	hp_work = kmalloc(sizeof(*hp_work), GFP_KERNEL);
+	if (!hp_work)
+		return;
+
+	hp_work->handle = handle;
+	hp_work->type = type;
+	hp_work->context = context;
+
+	INIT_WORK(&hp_work->work, func);
+	ret = queue_work(kacpi_hotplug_wq, &hp_work->work);
+	if (!ret)
+		kfree(hp_work);
+}
+EXPORT_SYMBOL_GPL(alloc_acpi_hp_work);

drivers/acpi/pci_irq.c

@@ -53,9 +53,6 @@ struct acpi_prt_entry {
 	u32			index;		/* GSI, or link _CRS index */
 };
 
-static LIST_HEAD(acpi_prt_list);
-static DEFINE_SPINLOCK(acpi_prt_lock);
-
 static inline char pin_name(int pin)
 {
 	return 'A' + pin - 1;
@@ -65,28 +62,6 @@ static inline char pin_name(int pin)
                          PCI IRQ Routing Table (PRT) Support
    -------------------------------------------------------------------------- */
 
-static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
-							  int pin)
-{
-	struct acpi_prt_entry *entry;
-	int segment = pci_domain_nr(dev->bus);
-	int bus = dev->bus->number;
-	int device = PCI_SLOT(dev->devfn);
-
-	spin_lock(&acpi_prt_lock);
-	list_for_each_entry(entry, &acpi_prt_list, list) {
-		if ((segment == entry->id.segment)
-		    && (bus == entry->id.bus)
-		    && (device == entry->id.device)
-		    && (pin == entry->pin)) {
-			spin_unlock(&acpi_prt_lock);
-			return entry;
-		}
-	}
-	spin_unlock(&acpi_prt_lock);
-	return NULL;
-}
-
 /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
 static const struct dmi_system_id medion_md9580[] = {
 	{
@@ -184,11 +159,19 @@ static void do_prt_fixups(struct acpi_prt_entry *entry,
 	}
 }
 
-static int acpi_pci_irq_add_entry(acpi_handle handle, int segment, int bus,
-				  struct acpi_pci_routing_table *prt)
+static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev,
+				  int pin, struct acpi_pci_routing_table *prt,
+				  struct acpi_prt_entry **entry_ptr)
 {
+	int segment = pci_domain_nr(dev->bus);
+	int bus = dev->bus->number;
+	int device = PCI_SLOT(dev->devfn);
 	struct acpi_prt_entry *entry;
 
+	if (((prt->address >> 16) & 0xffff) != device ||
+	    prt->pin + 1 != pin)
+		return -ENODEV;
+
 	entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
 	if (!entry)
 		return -ENOMEM;
@@ -237,43 +220,37 @@ static int acpi_pci_irq_add_entry(acpi_handle handle, int segment, int bus,
 			      entry->id.device, pin_name(entry->pin),
 			      prt->source, entry->index));
 
-	spin_lock(&acpi_prt_lock);
-	list_add_tail(&entry->list, &acpi_prt_list);
-	spin_unlock(&acpi_prt_lock);
+	*entry_ptr = entry;
 
 	return 0;
 }
 
-int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus)
+static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
+			  int pin, struct acpi_prt_entry **entry_ptr)
 {
 	acpi_status status;
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	struct acpi_pci_routing_table *entry;
+	acpi_handle handle = NULL;
 
-	/* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
-	status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
-	if (ACPI_FAILURE(status))
+	if (dev->bus->bridge)
+		handle = ACPI_HANDLE(dev->bus->bridge);
+
+	if (!handle)
 		return -ENODEV;
 
-	printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
-	       (char *) buffer.pointer);
-
-	kfree(buffer.pointer);
-
-	buffer.length = ACPI_ALLOCATE_BUFFER;
-	buffer.pointer = NULL;
-
+	/* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
 	status = acpi_get_irq_routing_table(handle, &buffer);
 	if (ACPI_FAILURE(status)) {
-		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]",
-				acpi_format_exception(status)));
 		kfree(buffer.pointer);
 		return -ENODEV;
 	}
 
 	entry = buffer.pointer;
 	while (entry && (entry->length > 0)) {
-		acpi_pci_irq_add_entry(handle, segment, bus, entry);
+		if (!acpi_pci_irq_check_entry(handle, dev, pin,
+						 entry, entry_ptr))
+			break;
 		entry = (struct acpi_pci_routing_table *)
 		    ((unsigned long)entry + entry->length);
 	}
@@ -282,23 +259,6 @@ int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus)
 	return 0;
 }
 
-void acpi_pci_irq_del_prt(int segment, int bus)
-{
-	struct acpi_prt_entry *entry, *tmp;
-
-	printk(KERN_DEBUG
-	       "ACPI: Delete PCI Interrupt Routing Table for %04x:%02x\n",
-	       segment, bus);
-	spin_lock(&acpi_prt_lock);
-	list_for_each_entry_safe(entry, tmp, &acpi_prt_list, list) {
-		if (segment == entry->id.segment && bus == entry->id.bus) {
-			list_del(&entry->list);
-			kfree(entry);
-		}
-	}
-	spin_unlock(&acpi_prt_lock);
-}
-
 /* --------------------------------------------------------------------------
                           PCI Interrupt Routing Support
    -------------------------------------------------------------------------- */
@@ -359,12 +319,13 @@ static int acpi_reroute_boot_interrupt(struct pci_dev *dev,
 
 static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
 {
-	struct acpi_prt_entry *entry;
+	struct acpi_prt_entry *entry = NULL;
 	struct pci_dev *bridge;
 	u8 bridge_pin, orig_pin = pin;
+	int ret;
 
-	entry = acpi_pci_irq_find_prt_entry(dev, pin);
-	if (entry) {
+	ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry);
+	if (!ret && entry) {
 #ifdef CONFIG_X86_IO_APIC
 		acpi_reroute_boot_interrupt(dev, entry);
 #endif /* CONFIG_X86_IO_APIC */
@@ -373,7 +334,7 @@ static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
 		return entry;
 	}
 
-	/* 
+	/*
 	 * Attempt to derive an IRQ for this device from a parent bridge's
 	 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
 	 */
@@ -393,8 +354,8 @@ static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
 			pin = bridge_pin;
 		}
 
-		entry = acpi_pci_irq_find_prt_entry(bridge, pin);
-		if (entry) {
+		ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry);
+		if (!ret && entry) {
 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 					 "Derived GSI for %s INT %c from %s\n",
 					 pci_name(dev), pin_name(orig_pin),
@@ -470,6 +431,7 @@ int acpi_pci_irq_enable(struct pci_dev *dev)
 			dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
 				 pin_name(pin));
 		}
+
 		return 0;
 	}
 
@@ -477,6 +439,7 @@ int acpi_pci_irq_enable(struct pci_dev *dev)
 	if (rc < 0) {
 		dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
 			 pin_name(pin));
+		kfree(entry);
 		return rc;
 	}
 	dev->irq = rc;
@@ -491,6 +454,7 @@ int acpi_pci_irq_enable(struct pci_dev *dev)
 		(triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
 		(polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
 
+	kfree(entry);
 	return 0;
 }
 
@@ -513,6 +477,8 @@ void acpi_pci_irq_disable(struct pci_dev *dev)
 	else
 		gsi = entry->index;
 
+	kfree(entry);
+
 	/*
 	 * TBD: It might be worth clearing dev->irq by magic constant
 	 * (e.g. PCI_UNDEFINED_IRQ).

drivers/acpi/pci_root.c

@@ -103,24 +103,6 @@ void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
 }
 EXPORT_SYMBOL(acpi_pci_unregister_driver);
 
-acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
-{
-	struct acpi_pci_root *root;
-	acpi_handle handle = NULL;
-	
-	mutex_lock(&acpi_pci_root_lock);
-	list_for_each_entry(root, &acpi_pci_roots, node)
-		if ((root->segment == (u16) seg) &&
-		    (root->secondary.start == (u16) bus)) {
-			handle = root->device->handle;
-			break;
-		}
-	mutex_unlock(&acpi_pci_root_lock);
-	return handle;
-}
-
-EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
-
 /**
  * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
  * @handle - the ACPI CA node in question.
@@ -431,7 +413,6 @@ static int acpi_pci_root_add(struct acpi_device *device,
 	acpi_status status;
 	int result;
 	struct acpi_pci_root *root;
-	acpi_handle handle;
 	struct acpi_pci_driver *driver;
 	u32 flags, base_flags;
 	bool is_osc_granted = false;
@@ -486,16 +467,6 @@ static int acpi_pci_root_add(struct acpi_device *device,
 	       acpi_device_name(device), acpi_device_bid(device),
 	       root->segment, &root->secondary);
 
-	/*
-	 * PCI Routing Table
-	 * -----------------
-	 * Evaluate and parse _PRT, if exists.
-	 */
-	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
-	if (ACPI_SUCCESS(status))
-		result = acpi_pci_irq_add_prt(device->handle, root->segment,
-					      root->secondary.start);
-
 	root->mcfg_addr = acpi_pci_root_get_mcfg_addr(device->handle);
 
 	/*
@@ -597,8 +568,10 @@ static int acpi_pci_root_add(struct acpi_device *device,
 	if (device->wakeup.flags.run_wake)
 		device_set_run_wake(root->bus->bridge, true);
 
-	if (system_state != SYSTEM_BOOTING)
+	if (system_state != SYSTEM_BOOTING) {
+		pcibios_resource_survey_bus(root->bus);
 		pci_assign_unassigned_bus_resources(root->bus);
+	}
 
 	mutex_lock(&acpi_pci_root_lock);
 	list_for_each_entry(driver, &acpi_pci_drivers, node)
@@ -618,7 +591,6 @@ out_del_root:
 	list_del(&root->node);
 	mutex_unlock(&acpi_pci_root_lock);
 
-	acpi_pci_irq_del_prt(root->segment, root->secondary.start);
 end:
 	kfree(root);
 	return result;
@@ -626,8 +598,6 @@ end:
 
 static void acpi_pci_root_remove(struct acpi_device *device)
 {
-	acpi_status status;
-	acpi_handle handle;
 	struct acpi_pci_root *root = acpi_driver_data(device);
 	struct acpi_pci_driver *driver;
 
@@ -642,10 +612,6 @@ static void acpi_pci_root_remove(struct acpi_device *device)
 	device_set_run_wake(root->bus->bridge, false);
 	pci_acpi_remove_bus_pm_notifier(device);
 
-	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
-	if (ACPI_SUCCESS(status))
-		acpi_pci_irq_del_prt(root->segment, root->secondary.start);
-
 	pci_remove_root_bus(root->bus);
 
 	mutex_lock(&acpi_pci_root_lock);
@@ -663,3 +629,133 @@ void __init acpi_pci_root_init(void)
 		acpi_scan_add_handler(&pci_root_handler);
 	}
 }
+/* Support root bridge hotplug */
+
+static void handle_root_bridge_insertion(acpi_handle handle)
+{
+	struct acpi_device *device;
+
+	if (!acpi_bus_get_device(handle, &device)) {
+		printk(KERN_DEBUG "acpi device exists...\n");
+		return;
+	}
+
+	if (acpi_bus_scan(handle))
+		printk(KERN_ERR "cannot add bridge to acpi list\n");
+}
+
+static void handle_root_bridge_removal(struct acpi_device *device)
+{
+	struct acpi_eject_event *ej_event;
+
+	ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
+	if (!ej_event) {
+		/* Inform firmware the hot-remove operation has error */
+		(void) acpi_evaluate_hotplug_ost(device->handle,
+					ACPI_NOTIFY_EJECT_REQUEST,
+					ACPI_OST_SC_NON_SPECIFIC_FAILURE,
+					NULL);
+		return;
+	}
+
+	ej_event->device = device;
+	ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
+
+	acpi_bus_hot_remove_device(ej_event);
+}
+
+static void _handle_hotplug_event_root(struct work_struct *work)
+{
+	struct acpi_pci_root *root;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER };
+	struct acpi_hp_work *hp_work;
+	acpi_handle handle;
+	u32 type;
+
+	hp_work = container_of(work, struct acpi_hp_work, work);
+	handle = hp_work->handle;
+	type = hp_work->type;
+
+	root = acpi_pci_find_root(handle);
+
+	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+
+	switch (type) {
+	case ACPI_NOTIFY_BUS_CHECK:
+		/* bus enumerate */
+		printk(KERN_DEBUG "%s: Bus check notify on %s\n", __func__,
+				 (char *)buffer.pointer);
+		if (!root)
+			handle_root_bridge_insertion(handle);
+
+		break;
+
+	case ACPI_NOTIFY_DEVICE_CHECK:
+		/* device check */
+		printk(KERN_DEBUG "%s: Device check notify on %s\n", __func__,
+				 (char *)buffer.pointer);
+		if (!root)
+			handle_root_bridge_insertion(handle);
+		break;
+
+	case ACPI_NOTIFY_EJECT_REQUEST:
+		/* request device eject */
+		printk(KERN_DEBUG "%s: Device eject notify on %s\n", __func__,
+				 (char *)buffer.pointer);
+		if (root)
+			handle_root_bridge_removal(root->device);
+		break;
+	default:
+		printk(KERN_WARNING "notify_handler: unknown event type 0x%x for %s\n",
+				 type, (char *)buffer.pointer);
+		break;
+	}
+
+	kfree(hp_work); /* allocated in handle_hotplug_event_bridge */
+	kfree(buffer.pointer);
+}
+
+static void handle_hotplug_event_root(acpi_handle handle, u32 type,
+					void *context)
+{
+	alloc_acpi_hp_work(handle, type, context,
+				_handle_hotplug_event_root);
+}
+
+static acpi_status __init
+find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+	acpi_status status;
+	char objname[64];
+	struct acpi_buffer buffer = { .length = sizeof(objname),
+				      .pointer = objname };
+	int *count = (int *)context;
+
+	if (!acpi_is_root_bridge(handle))
+		return AE_OK;
+
+	(*count)++;
+
+	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+
+	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+					handle_hotplug_event_root, NULL);
+	if (ACPI_FAILURE(status))
+		printk(KERN_DEBUG "acpi root: %s notify handler is not installed, exit status: %u\n",
+				  objname, (unsigned int)status);
+	else
+		printk(KERN_DEBUG "acpi root: %s notify handler is installed\n",
+				 objname);
+
+	return AE_OK;
+}
+
+void __init acpi_pci_root_hp_init(void)
+{
+	int num = 0;
+
+	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+		ACPI_UINT32_MAX, find_root_bridges, NULL, &num, NULL);
+
+	printk(KERN_DEBUG "Found %d acpi root devices\n", num);
+}

drivers/acpi/pci_slot.c

@@ -329,19 +329,8 @@ static struct dmi_system_id acpi_pci_slot_dmi_table[] __initdata = {
 	{}
 };
 
-static int __init
-acpi_pci_slot_init(void)
+void __init acpi_pci_slot_init(void)
 {
 	dmi_check_system(acpi_pci_slot_dmi_table);
 	acpi_pci_register_driver(&acpi_pci_slot_driver);
-	return 0;
 }
-
-static void __exit
-acpi_pci_slot_exit(void)
-{
-	acpi_pci_unregister_driver(&acpi_pci_slot_driver);
-}
-
-module_init(acpi_pci_slot_init);
-module_exit(acpi_pci_slot_exit);

drivers/acpi/scan.c

@@ -1783,6 +1783,7 @@ int __init acpi_scan_init(void)
 	acpi_platform_init();
 	acpi_csrt_init();
 	acpi_container_init();
+	acpi_pci_slot_init();
 
 	mutex_lock(&acpi_scan_lock);
 	/*
@@ -1804,6 +1805,8 @@ int __init acpi_scan_init(void)
 
 	acpi_update_all_gpes();
 
+	acpi_pci_root_hp_init();
+
  out:
 	mutex_unlock(&acpi_scan_lock);
 	return result;