2 * pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or (at
12 * your option) any later version.
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/types.h>
30 #include <linux/mutex.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/pci.h>
34 #include <linux/pci-acpi.h>
35 #include <linux/pci-aspm.h>
36 #include <linux/acpi.h>
37 #include <linux/slab.h>
38 #include <acpi/acpi_bus.h>
39 #include <acpi/acpi_drivers.h>
40 #include <acpi/apei.h>
42 #define PREFIX "ACPI: "
44 #define _COMPONENT ACPI_PCI_COMPONENT
45 ACPI_MODULE_NAME("pci_root");
46 #define ACPI_PCI_ROOT_CLASS "pci_bridge"
47 #define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
48 static int acpi_pci_root_add(struct acpi_device *device,
49 const struct acpi_device_id *not_used);
50 static void acpi_pci_root_remove(struct acpi_device *device);
52 #define ACPI_PCIE_REQ_SUPPORT (OSC_EXT_PCI_CONFIG_SUPPORT \
53 | OSC_ACTIVE_STATE_PWR_SUPPORT \
54 | OSC_CLOCK_PWR_CAPABILITY_SUPPORT \
57 static const struct acpi_device_id root_device_ids[] = {
62 static struct acpi_scan_handler pci_root_handler = {
63 .ids = root_device_ids,
64 .attach = acpi_pci_root_add,
65 .detach = acpi_pci_root_remove,
71 /* Lock to protect both acpi_pci_roots lists */
72 static DEFINE_MUTEX(acpi_pci_root_lock);
73 static LIST_HEAD(acpi_pci_roots);
75 static DEFINE_MUTEX(osc_lock);
78 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
79 * @handle - the ACPI CA node in question.
81 * Note: we could make this API take a struct acpi_device * instead, but
82 * for now, it's more convenient to operate on an acpi_handle.
84 int acpi_is_root_bridge(acpi_handle handle)
87 struct acpi_device *device;
89 ret = acpi_bus_get_device(handle, &device);
93 ret = acpi_match_device_ids(device, root_device_ids);
99 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
102 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
104 struct resource *res = data;
105 struct acpi_resource_address64 address;
107 if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
108 resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
109 resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
112 acpi_resource_to_address64(resource, &address);
113 if ((address.address_length > 0) &&
114 (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
115 res->start = address.minimum;
116 res->end = address.minimum + address.address_length - 1;
122 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
123 struct resource *res)
129 acpi_walk_resources(handle, METHOD_NAME__CRS,
130 get_root_bridge_busnr_callback, res);
131 if (ACPI_FAILURE(status))
133 if (res->start == -1)
138 static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
140 static acpi_status acpi_pci_run_osc(acpi_handle handle,
141 const u32 *capbuf, u32 *retval)
143 struct acpi_osc_context context = {
144 .uuid_str = pci_osc_uuid_str,
147 .cap.pointer = (void *)capbuf,
151 status = acpi_run_osc(handle, &context);
152 if (ACPI_SUCCESS(status)) {
153 *retval = *((u32 *)(context.ret.pointer + 8));
154 kfree(context.ret.pointer);
159 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
164 u32 result, capbuf[3];
166 support &= OSC_PCI_SUPPORT_MASKS;
167 support |= root->osc_support_set;
169 capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
170 capbuf[OSC_SUPPORT_TYPE] = support;
172 *control &= OSC_PCI_CONTROL_MASKS;
173 capbuf[OSC_CONTROL_TYPE] = *control | root->osc_control_set;
175 /* Run _OSC query only with existing controls. */
176 capbuf[OSC_CONTROL_TYPE] = root->osc_control_set;
179 status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
180 if (ACPI_SUCCESS(status)) {
181 root->osc_support_set = support;
188 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
193 status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
194 if (ACPI_FAILURE(status))
196 mutex_lock(&osc_lock);
197 status = acpi_pci_query_osc(root, flags, NULL);
198 mutex_unlock(&osc_lock);
202 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
204 struct acpi_pci_root *root;
205 struct acpi_device *device;
207 if (acpi_bus_get_device(handle, &device) ||
208 acpi_match_device_ids(device, root_device_ids))
211 root = acpi_driver_data(device);
215 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
217 struct acpi_handle_node {
218 struct list_head node;
223 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
224 * @handle: the handle in question
226 * Given an ACPI CA handle, the desired PCI device is located in the
227 * list of PCI devices.
229 * If the device is found, its reference count is increased and this
230 * function returns a pointer to its data structure. The caller must
231 * decrement the reference count by calling pci_dev_put().
232 * If no device is found, %NULL is returned.
234 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
237 unsigned long long adr;
240 struct pci_bus *pbus;
241 struct pci_dev *pdev = NULL;
242 struct acpi_handle_node *node, *tmp;
243 struct acpi_pci_root *root;
244 LIST_HEAD(device_list);
247 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
250 while (!acpi_is_root_bridge(phandle)) {
251 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
255 INIT_LIST_HEAD(&node->node);
256 node->handle = phandle;
257 list_add(&node->node, &device_list);
259 status = acpi_get_parent(phandle, &phandle);
260 if (ACPI_FAILURE(status))
264 root = acpi_pci_find_root(phandle);
271 * Now, walk back down the PCI device tree until we return to our
272 * original handle. Assumes that everything between the PCI root
273 * bridge and the device we're looking for must be a P2P bridge.
275 list_for_each_entry(node, &device_list, node) {
276 acpi_handle hnd = node->handle;
277 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
278 if (ACPI_FAILURE(status))
280 dev = (adr >> 16) & 0xffff;
283 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
284 if (!pdev || hnd == handle)
287 pbus = pdev->subordinate;
291 * This function may be called for a non-PCI device that has a
292 * PCI parent (eg. a disk under a PCI SATA controller). In that
293 * case pdev->subordinate will be NULL for the parent.
296 dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
302 list_for_each_entry_safe(node, tmp, &device_list, node)
307 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
310 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
311 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
312 * @mask: Mask of _OSC bits to request control of, place to store control mask.
313 * @req: Mask of _OSC bits the control of is essential to the caller.
315 * Run _OSC query for @mask and if that is successful, compare the returned
316 * mask of control bits with @req. If all of the @req bits are set in the
317 * returned mask, run _OSC request for it.
319 * The variable at the @mask address may be modified regardless of whether or
320 * not the function returns success. On success it will contain the mask of
321 * _OSC bits the BIOS has granted control of, but its contents are meaningless
324 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
326 struct acpi_pci_root *root;
332 return AE_BAD_PARAMETER;
334 ctrl = *mask & OSC_PCI_CONTROL_MASKS;
335 if ((ctrl & req) != req)
338 root = acpi_pci_find_root(handle);
342 status = acpi_get_handle(handle, "_OSC", &tmp);
343 if (ACPI_FAILURE(status))
346 mutex_lock(&osc_lock);
348 *mask = ctrl | root->osc_control_set;
349 /* No need to evaluate _OSC if the control was already granted. */
350 if ((root->osc_control_set & ctrl) == ctrl)
353 /* Need to check the available controls bits before requesting them. */
355 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
356 if (ACPI_FAILURE(status))
363 if ((ctrl & req) != req) {
368 capbuf[OSC_QUERY_TYPE] = 0;
369 capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
370 capbuf[OSC_CONTROL_TYPE] = ctrl;
371 status = acpi_pci_run_osc(handle, capbuf, mask);
372 if (ACPI_SUCCESS(status))
373 root->osc_control_set = *mask;
375 mutex_unlock(&osc_lock);
378 EXPORT_SYMBOL(acpi_pci_osc_control_set);
380 static int acpi_pci_root_add(struct acpi_device *device,
381 const struct acpi_device_id *not_used)
383 unsigned long long segment, bus;
386 struct acpi_pci_root *root;
387 u32 flags, base_flags;
389 root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
394 status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
396 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
397 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
402 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
403 root->secondary.flags = IORESOURCE_BUS;
404 status = try_get_root_bridge_busnr(device->handle, &root->secondary);
405 if (ACPI_FAILURE(status)) {
407 * We need both the start and end of the downstream bus range
408 * to interpret _CBA (MMCONFIG base address), so it really is
409 * supposed to be in _CRS. If we don't find it there, all we
410 * can do is assume [_BBN-0xFF] or [0-0xFF].
412 root->secondary.end = 0xFF;
413 printk(KERN_WARNING FW_BUG PREFIX
414 "no secondary bus range in _CRS\n");
415 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,
417 if (ACPI_SUCCESS(status))
418 root->secondary.start = bus;
419 else if (status == AE_NOT_FOUND)
420 root->secondary.start = 0;
422 printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
428 INIT_LIST_HEAD(&root->node);
429 root->device = device;
430 root->segment = segment & 0xFFFF;
431 strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
432 strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
433 device->driver_data = root;
435 printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
436 acpi_device_name(device), acpi_device_bid(device),
437 root->segment, &root->secondary);
439 root->mcfg_addr = acpi_pci_root_get_mcfg_addr(device->handle);
442 * All supported architectures that use ACPI have support for
443 * PCI domains, so we indicate this in _OSC support capabilities.
445 flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
446 acpi_pci_osc_support(root, flags);
449 * TBD: Need PCI interface for enumeration/configuration of roots.
452 mutex_lock(&acpi_pci_root_lock);
453 list_add_tail(&root->node, &acpi_pci_roots);
454 mutex_unlock(&acpi_pci_root_lock);
457 * Scan the Root Bridge
458 * --------------------
459 * Must do this prior to any attempt to bind the root device, as the
460 * PCI namespace does not get created until this call is made (and
461 * thus the root bridge's pci_dev does not exist).
463 root->bus = pci_acpi_scan_root(root);
465 printk(KERN_ERR PREFIX
466 "Bus %04x:%02x not present in PCI namespace\n",
467 root->segment, (unsigned int)root->secondary.start);
472 /* Indicate support for various _OSC capabilities. */
473 if (pci_ext_cfg_avail())
474 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
475 if (pcie_aspm_support_enabled()) {
476 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
477 OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
479 if (pci_msi_enabled())
480 flags |= OSC_MSI_SUPPORT;
481 if (flags != base_flags) {
482 status = acpi_pci_osc_support(root, flags);
483 if (ACPI_FAILURE(status)) {
484 dev_info(&device->dev, "ACPI _OSC support "
485 "notification failed, disabling PCIe ASPM\n");
491 if (!pcie_ports_disabled
492 && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) {
493 flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
494 | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
495 | OSC_PCI_EXPRESS_PME_CONTROL;
497 if (pci_aer_available()) {
498 if (aer_acpi_firmware_first())
499 dev_dbg(&device->dev,
500 "PCIe errors handled by BIOS.\n");
502 flags |= OSC_PCI_EXPRESS_AER_CONTROL;
505 dev_info(&device->dev,
506 "Requesting ACPI _OSC control (0x%02x)\n", flags);
508 status = acpi_pci_osc_control_set(device->handle, &flags,
509 OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
510 if (ACPI_SUCCESS(status)) {
511 dev_info(&device->dev,
512 "ACPI _OSC control (0x%02x) granted\n", flags);
513 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
515 * We have ASPM control, but the FADT indicates
516 * that it's unsupported. Clear it.
518 pcie_clear_aspm(root->bus);
521 dev_info(&device->dev,
522 "ACPI _OSC request failed (%s), "
523 "returned control mask: 0x%02x\n",
524 acpi_format_exception(status), flags);
525 pr_info("ACPI _OSC control for PCIe not granted, "
530 dev_info(&device->dev,
531 "Unable to request _OSC control "
532 "(_OSC support mask: 0x%02x)\n", flags);
535 pci_acpi_add_bus_pm_notifier(device, root->bus);
536 if (device->wakeup.flags.run_wake)
537 device_set_run_wake(root->bus->bridge, true);
539 if (system_state != SYSTEM_BOOTING) {
540 pcibios_resource_survey_bus(root->bus);
541 pci_assign_unassigned_bus_resources(root->bus);
544 /* need to after hot-added ioapic is registered */
545 if (system_state != SYSTEM_BOOTING)
546 pci_enable_bridges(root->bus);
548 pci_bus_add_devices(root->bus);
552 mutex_lock(&acpi_pci_root_lock);
553 list_del(&root->node);
554 mutex_unlock(&acpi_pci_root_lock);
561 static void acpi_pci_root_remove(struct acpi_device *device)
563 struct acpi_pci_root *root = acpi_driver_data(device);
565 pci_stop_root_bus(root->bus);
567 device_set_run_wake(root->bus->bridge, false);
568 pci_acpi_remove_bus_pm_notifier(device);
570 pci_remove_root_bus(root->bus);
572 mutex_lock(&acpi_pci_root_lock);
573 list_del(&root->node);
574 mutex_unlock(&acpi_pci_root_lock);
578 void __init acpi_pci_root_init(void)
582 if (!acpi_pci_disabled) {
583 pci_acpi_crs_quirks();
584 acpi_scan_add_handler(&pci_root_handler);
587 /* Support root bridge hotplug */
589 static void handle_root_bridge_insertion(acpi_handle handle)
591 struct acpi_device *device;
593 if (!acpi_bus_get_device(handle, &device)) {
594 printk(KERN_DEBUG "acpi device exists...\n");
598 if (acpi_bus_scan(handle))
599 printk(KERN_ERR "cannot add bridge to acpi list\n");
602 static void handle_root_bridge_removal(struct acpi_device *device)
605 struct acpi_eject_event *ej_event;
607 ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
609 /* Inform firmware the hot-remove operation has error */
610 (void) acpi_evaluate_hotplug_ost(device->handle,
611 ACPI_NOTIFY_EJECT_REQUEST,
612 ACPI_OST_SC_NON_SPECIFIC_FAILURE,
617 ej_event->device = device;
618 ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
620 get_device(&device->dev);
621 status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, ej_event);
622 if (ACPI_FAILURE(status)) {
623 put_device(&device->dev);
628 static void _handle_hotplug_event_root(struct work_struct *work)
630 struct acpi_pci_root *root;
631 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER };
632 struct acpi_hp_work *hp_work;
636 hp_work = container_of(work, struct acpi_hp_work, work);
637 handle = hp_work->handle;
638 type = hp_work->type;
640 acpi_scan_lock_acquire();
642 root = acpi_pci_find_root(handle);
643 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
646 case ACPI_NOTIFY_BUS_CHECK:
648 printk(KERN_DEBUG "%s: Bus check notify on %s\n", __func__,
649 (char *)buffer.pointer);
651 acpiphp_check_host_bridge(handle);
653 handle_root_bridge_insertion(handle);
657 case ACPI_NOTIFY_DEVICE_CHECK:
659 printk(KERN_DEBUG "%s: Device check notify on %s\n", __func__,
660 (char *)buffer.pointer);
662 handle_root_bridge_insertion(handle);
665 case ACPI_NOTIFY_EJECT_REQUEST:
666 /* request device eject */
667 printk(KERN_DEBUG "%s: Device eject notify on %s\n", __func__,
668 (char *)buffer.pointer);
670 handle_root_bridge_removal(root->device);
673 printk(KERN_WARNING "notify_handler: unknown event type 0x%x for %s\n",
674 type, (char *)buffer.pointer);
678 acpi_scan_lock_release();
679 kfree(hp_work); /* allocated in handle_hotplug_event_bridge */
680 kfree(buffer.pointer);
683 static void handle_hotplug_event_root(acpi_handle handle, u32 type,
686 alloc_acpi_hp_work(handle, type, context,
687 _handle_hotplug_event_root);
690 static acpi_status __init
691 find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
695 struct acpi_buffer buffer = { .length = sizeof(objname),
696 .pointer = objname };
697 int *count = (int *)context;
699 if (!acpi_is_root_bridge(handle))
704 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
706 status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
707 handle_hotplug_event_root, NULL);
708 if (ACPI_FAILURE(status))
709 printk(KERN_DEBUG "acpi root: %s notify handler is not installed, exit status: %u\n",
710 objname, (unsigned int)status);
712 printk(KERN_DEBUG "acpi root: %s notify handler is installed\n",
718 void __init acpi_pci_root_hp_init(void)
722 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
723 ACPI_UINT32_MAX, find_root_bridges, NULL, &num, NULL);
725 printk(KERN_DEBUG "Found %d acpi root devices\n", num);