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 static int acpi_pci_root_remove(struct acpi_device *device, int type);
50 static int acpi_pci_root_start(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[] = {
61 MODULE_DEVICE_TABLE(acpi, root_device_ids);
63 static struct acpi_driver acpi_pci_root_driver = {
65 .class = ACPI_PCI_ROOT_CLASS,
66 .ids = root_device_ids,
68 .add = acpi_pci_root_add,
69 .remove = acpi_pci_root_remove,
70 .start = acpi_pci_root_start,
74 /* Lock to protect both acpi_pci_roots and acpi_pci_drivers lists */
75 static DEFINE_MUTEX(acpi_pci_root_lock);
76 static LIST_HEAD(acpi_pci_roots);
77 static LIST_HEAD(acpi_pci_drivers);
79 static DEFINE_MUTEX(osc_lock);
81 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
84 struct acpi_pci_root *root;
86 mutex_lock(&acpi_pci_root_lock);
87 list_add_tail(&driver->node, &acpi_pci_drivers);
89 list_for_each_entry(root, &acpi_pci_roots, node) {
93 mutex_unlock(&acpi_pci_root_lock);
97 EXPORT_SYMBOL(acpi_pci_register_driver);
99 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
101 struct acpi_pci_root *root;
103 mutex_lock(&acpi_pci_root_lock);
104 list_del(&driver->node);
106 list_for_each_entry(root, &acpi_pci_roots, node)
107 driver->remove(root);
108 mutex_unlock(&acpi_pci_root_lock);
110 EXPORT_SYMBOL(acpi_pci_unregister_driver);
112 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
114 struct acpi_pci_root *root;
115 acpi_handle handle = NULL;
117 mutex_lock(&acpi_pci_root_lock);
118 list_for_each_entry(root, &acpi_pci_roots, node)
119 if ((root->segment == (u16) seg) &&
120 (root->secondary.start == (u16) bus)) {
121 handle = root->device->handle;
124 mutex_unlock(&acpi_pci_root_lock);
128 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
131 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
132 * @handle - the ACPI CA node in question.
134 * Note: we could make this API take a struct acpi_device * instead, but
135 * for now, it's more convenient to operate on an acpi_handle.
137 int acpi_is_root_bridge(acpi_handle handle)
140 struct acpi_device *device;
142 ret = acpi_bus_get_device(handle, &device);
146 ret = acpi_match_device_ids(device, root_device_ids);
152 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
155 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
157 struct resource *res = data;
158 struct acpi_resource_address64 address;
160 if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
161 resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
162 resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
165 acpi_resource_to_address64(resource, &address);
166 if ((address.address_length > 0) &&
167 (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
168 res->start = address.minimum;
169 res->end = address.minimum + address.address_length - 1;
175 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
176 struct resource *res)
182 acpi_walk_resources(handle, METHOD_NAME__CRS,
183 get_root_bridge_busnr_callback, res);
184 if (ACPI_FAILURE(status))
186 if (res->start == -1)
191 static void acpi_pci_bridge_scan(struct acpi_device *device)
194 struct acpi_device *child = NULL;
196 if (device->flags.bus_address)
197 if (device->parent && device->parent->ops.bind) {
198 status = device->parent->ops.bind(device);
200 list_for_each_entry(child, &device->children, node)
201 acpi_pci_bridge_scan(child);
206 static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
208 static acpi_status acpi_pci_run_osc(acpi_handle handle,
209 const u32 *capbuf, u32 *retval)
211 struct acpi_osc_context context = {
212 .uuid_str = pci_osc_uuid_str,
215 .cap.pointer = (void *)capbuf,
219 status = acpi_run_osc(handle, &context);
220 if (ACPI_SUCCESS(status)) {
221 *retval = *((u32 *)(context.ret.pointer + 8));
222 kfree(context.ret.pointer);
227 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
232 u32 result, capbuf[3];
234 support &= OSC_PCI_SUPPORT_MASKS;
235 support |= root->osc_support_set;
237 capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
238 capbuf[OSC_SUPPORT_TYPE] = support;
240 *control &= OSC_PCI_CONTROL_MASKS;
241 capbuf[OSC_CONTROL_TYPE] = *control | root->osc_control_set;
243 /* Run _OSC query for all possible controls. */
244 capbuf[OSC_CONTROL_TYPE] = OSC_PCI_CONTROL_MASKS;
247 status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
248 if (ACPI_SUCCESS(status)) {
249 root->osc_support_set = support;
256 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
261 status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
262 if (ACPI_FAILURE(status))
264 mutex_lock(&osc_lock);
265 status = acpi_pci_query_osc(root, flags, NULL);
266 mutex_unlock(&osc_lock);
270 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
272 struct acpi_pci_root *root;
273 struct acpi_device *device;
275 if (acpi_bus_get_device(handle, &device) ||
276 acpi_match_device_ids(device, root_device_ids))
279 root = acpi_driver_data(device);
283 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
285 struct acpi_handle_node {
286 struct list_head node;
291 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
292 * @handle: the handle in question
294 * Given an ACPI CA handle, the desired PCI device is located in the
295 * list of PCI devices.
297 * If the device is found, its reference count is increased and this
298 * function returns a pointer to its data structure. The caller must
299 * decrement the reference count by calling pci_dev_put().
300 * If no device is found, %NULL is returned.
302 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
305 unsigned long long adr;
308 struct pci_bus *pbus;
309 struct pci_dev *pdev = NULL;
310 struct acpi_handle_node *node, *tmp;
311 struct acpi_pci_root *root;
312 LIST_HEAD(device_list);
315 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
318 while (!acpi_is_root_bridge(phandle)) {
319 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
323 INIT_LIST_HEAD(&node->node);
324 node->handle = phandle;
325 list_add(&node->node, &device_list);
327 status = acpi_get_parent(phandle, &phandle);
328 if (ACPI_FAILURE(status))
332 root = acpi_pci_find_root(phandle);
339 * Now, walk back down the PCI device tree until we return to our
340 * original handle. Assumes that everything between the PCI root
341 * bridge and the device we're looking for must be a P2P bridge.
343 list_for_each_entry(node, &device_list, node) {
344 acpi_handle hnd = node->handle;
345 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
346 if (ACPI_FAILURE(status))
348 dev = (adr >> 16) & 0xffff;
351 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
352 if (!pdev || hnd == handle)
355 pbus = pdev->subordinate;
359 * This function may be called for a non-PCI device that has a
360 * PCI parent (eg. a disk under a PCI SATA controller). In that
361 * case pdev->subordinate will be NULL for the parent.
364 dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
370 list_for_each_entry_safe(node, tmp, &device_list, node)
375 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
378 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
379 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
380 * @mask: Mask of _OSC bits to request control of, place to store control mask.
381 * @req: Mask of _OSC bits the control of is essential to the caller.
383 * Run _OSC query for @mask and if that is successful, compare the returned
384 * mask of control bits with @req. If all of the @req bits are set in the
385 * returned mask, run _OSC request for it.
387 * The variable at the @mask address may be modified regardless of whether or
388 * not the function returns success. On success it will contain the mask of
389 * _OSC bits the BIOS has granted control of, but its contents are meaningless
392 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
394 struct acpi_pci_root *root;
400 return AE_BAD_PARAMETER;
402 ctrl = *mask & OSC_PCI_CONTROL_MASKS;
403 if ((ctrl & req) != req)
406 root = acpi_pci_find_root(handle);
410 status = acpi_get_handle(handle, "_OSC", &tmp);
411 if (ACPI_FAILURE(status))
414 mutex_lock(&osc_lock);
416 *mask = ctrl | root->osc_control_set;
417 /* No need to evaluate _OSC if the control was already granted. */
418 if ((root->osc_control_set & ctrl) == ctrl)
421 /* Need to check the available controls bits before requesting them. */
423 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
424 if (ACPI_FAILURE(status))
431 if ((ctrl & req) != req) {
436 capbuf[OSC_QUERY_TYPE] = 0;
437 capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
438 capbuf[OSC_CONTROL_TYPE] = ctrl;
439 status = acpi_pci_run_osc(handle, capbuf, mask);
440 if (ACPI_SUCCESS(status))
441 root->osc_control_set = *mask;
443 mutex_unlock(&osc_lock);
446 EXPORT_SYMBOL(acpi_pci_osc_control_set);
448 static int acpi_pci_root_add(struct acpi_device *device)
450 unsigned long long segment, bus;
453 struct acpi_pci_root *root;
455 struct acpi_device *child;
456 u32 flags, base_flags;
457 bool is_osc_granted = false;
459 root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
464 status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
466 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
467 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
472 /* Check _CRS first, then _BBN. If no _BBN, default to zero. */
473 root->secondary.flags = IORESOURCE_BUS;
474 status = try_get_root_bridge_busnr(device->handle, &root->secondary);
475 if (ACPI_FAILURE(status)) {
477 * We need both the start and end of the downstream bus range
478 * to interpret _CBA (MMCONFIG base address), so it really is
479 * supposed to be in _CRS. If we don't find it there, all we
480 * can do is assume [_BBN-0xFF] or [0-0xFF].
482 root->secondary.end = 0xFF;
483 printk(KERN_WARNING FW_BUG PREFIX
484 "no secondary bus range in _CRS\n");
485 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,
487 if (ACPI_SUCCESS(status))
488 root->secondary.start = bus;
489 else if (status == AE_NOT_FOUND)
490 root->secondary.start = 0;
492 printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
498 INIT_LIST_HEAD(&root->node);
499 root->device = device;
500 root->segment = segment & 0xFFFF;
501 strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
502 strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
503 device->driver_data = root;
505 printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
506 acpi_device_name(device), acpi_device_bid(device),
507 root->segment, &root->secondary);
512 * Evaluate and parse _PRT, if exists.
514 status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
515 if (ACPI_SUCCESS(status))
516 result = acpi_pci_irq_add_prt(device->handle, root->segment,
517 root->secondary.start);
519 root->mcfg_addr = acpi_pci_root_get_mcfg_addr(device->handle);
522 * All supported architectures that use ACPI have support for
523 * PCI domains, so we indicate this in _OSC support capabilities.
525 flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
526 acpi_pci_osc_support(root, flags);
528 /* Indicate support for various _OSC capabilities. */
529 if (pci_ext_cfg_avail())
530 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
531 if (pcie_aspm_support_enabled()) {
532 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
533 OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
535 if (pci_msi_enabled())
536 flags |= OSC_MSI_SUPPORT;
537 if (flags != base_flags) {
538 status = acpi_pci_osc_support(root, flags);
539 if (ACPI_FAILURE(status)) {
540 dev_info(&device->dev, "ACPI _OSC support "
541 "notification failed, disabling PCIe ASPM\n");
546 if (!pcie_ports_disabled
547 && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) {
548 flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
549 | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
550 | OSC_PCI_EXPRESS_PME_CONTROL;
552 if (pci_aer_available()) {
553 if (aer_acpi_firmware_first())
554 dev_dbg(&device->dev,
555 "PCIe errors handled by BIOS.\n");
557 flags |= OSC_PCI_EXPRESS_AER_CONTROL;
560 dev_info(&device->dev,
561 "Requesting ACPI _OSC control (0x%02x)\n", flags);
563 status = acpi_pci_osc_control_set(device->handle, &flags,
564 OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
565 if (ACPI_SUCCESS(status)) {
566 is_osc_granted = true;
567 dev_info(&device->dev,
568 "ACPI _OSC control (0x%02x) granted\n", flags);
570 is_osc_granted = false;
571 dev_info(&device->dev,
572 "ACPI _OSC request failed (%s), "
573 "returned control mask: 0x%02x\n",
574 acpi_format_exception(status), flags);
577 dev_info(&device->dev,
578 "Unable to request _OSC control "
579 "(_OSC support mask: 0x%02x)\n", flags);
583 * TBD: Need PCI interface for enumeration/configuration of roots.
586 mutex_lock(&acpi_pci_root_lock);
587 list_add_tail(&root->node, &acpi_pci_roots);
588 mutex_unlock(&acpi_pci_root_lock);
591 * Scan the Root Bridge
592 * --------------------
593 * Must do this prior to any attempt to bind the root device, as the
594 * PCI namespace does not get created until this call is made (and
595 * thus the root bridge's pci_dev does not exist).
597 root->bus = pci_acpi_scan_root(root);
599 printk(KERN_ERR PREFIX
600 "Bus %04x:%02x not present in PCI namespace\n",
601 root->segment, (unsigned int)root->secondary.start);
607 * Attach ACPI-PCI Context
608 * -----------------------
609 * Thus binding the ACPI and PCI devices.
611 result = acpi_pci_bind_root(device);
616 * Scan and bind all _ADR-Based Devices
618 list_for_each_entry(child, &device->children, node)
619 acpi_pci_bridge_scan(child);
622 if (is_osc_granted) {
623 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM)
624 pcie_clear_aspm(root->bus);
626 pr_info("ACPI _OSC control for PCIe not granted, "
631 pci_acpi_add_bus_pm_notifier(device, root->bus);
632 if (device->wakeup.flags.run_wake)
633 device_set_run_wake(root->bus->bridge, true);
638 mutex_lock(&acpi_pci_root_lock);
639 list_del(&root->node);
640 mutex_unlock(&acpi_pci_root_lock);
642 acpi_pci_irq_del_prt(root->segment, root->secondary.start);
648 static int acpi_pci_root_start(struct acpi_device *device)
650 struct acpi_pci_root *root = acpi_driver_data(device);
651 struct acpi_pci_driver *driver;
653 if (system_state != SYSTEM_BOOTING)
654 pci_assign_unassigned_bus_resources(root->bus);
656 mutex_lock(&acpi_pci_root_lock);
657 list_for_each_entry(driver, &acpi_pci_drivers, node)
660 mutex_unlock(&acpi_pci_root_lock);
662 /* need to after hot-added ioapic is registered */
663 if (system_state != SYSTEM_BOOTING)
664 pci_enable_bridges(root->bus);
666 pci_bus_add_devices(root->bus);
671 static int acpi_pci_root_remove(struct acpi_device *device, int type)
675 struct acpi_pci_root *root = acpi_driver_data(device);
676 struct acpi_pci_driver *driver;
678 pci_stop_root_bus(root->bus);
680 mutex_lock(&acpi_pci_root_lock);
681 list_for_each_entry_reverse(driver, &acpi_pci_drivers, node)
683 driver->remove(root);
684 mutex_unlock(&acpi_pci_root_lock);
686 device_set_run_wake(root->bus->bridge, false);
687 pci_acpi_remove_bus_pm_notifier(device);
689 status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
690 if (ACPI_SUCCESS(status))
691 acpi_pci_irq_del_prt(root->segment, root->secondary.start);
693 pci_remove_root_bus(root->bus);
695 mutex_lock(&acpi_pci_root_lock);
696 list_del(&root->node);
697 mutex_unlock(&acpi_pci_root_lock);
702 static int __init acpi_pci_root_init(void)
706 if (acpi_pci_disabled)
709 pci_acpi_crs_quirks();
710 if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
716 subsys_initcall(acpi_pci_root_init);