Merge tag 'please-pull-misc-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-3.10.git] / drivers / acpi / pci_root.c
1 /*
2  *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
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.
13  *
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.
18  *
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.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  */
25
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>
31 #include <linux/pm.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>
41
42 #define PREFIX "ACPI: "
43
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);
51
52 #define ACPI_PCIE_REQ_SUPPORT (OSC_EXT_PCI_CONFIG_SUPPORT \
53                                 | OSC_ACTIVE_STATE_PWR_SUPPORT \
54                                 | OSC_CLOCK_PWR_CAPABILITY_SUPPORT \
55                                 | OSC_MSI_SUPPORT)
56
57 static const struct acpi_device_id root_device_ids[] = {
58         {"PNP0A03", 0},
59         {"", 0},
60 };
61
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,
66 };
67
68 /* Lock to protect both acpi_pci_roots and acpi_pci_drivers lists */
69 static DEFINE_MUTEX(acpi_pci_root_lock);
70 static LIST_HEAD(acpi_pci_roots);
71 static LIST_HEAD(acpi_pci_drivers);
72
73 static DEFINE_MUTEX(osc_lock);
74
75 int acpi_pci_register_driver(struct acpi_pci_driver *driver)
76 {
77         int n = 0;
78         struct acpi_pci_root *root;
79
80         mutex_lock(&acpi_pci_root_lock);
81         list_add_tail(&driver->node, &acpi_pci_drivers);
82         if (driver->add)
83                 list_for_each_entry(root, &acpi_pci_roots, node) {
84                         driver->add(root);
85                         n++;
86                 }
87         mutex_unlock(&acpi_pci_root_lock);
88
89         return n;
90 }
91 EXPORT_SYMBOL(acpi_pci_register_driver);
92
93 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
94 {
95         struct acpi_pci_root *root;
96
97         mutex_lock(&acpi_pci_root_lock);
98         list_del(&driver->node);
99         if (driver->remove)
100                 list_for_each_entry(root, &acpi_pci_roots, node)
101                         driver->remove(root);
102         mutex_unlock(&acpi_pci_root_lock);
103 }
104 EXPORT_SYMBOL(acpi_pci_unregister_driver);
105
106 /**
107  * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
108  * @handle - the ACPI CA node in question.
109  *
110  * Note: we could make this API take a struct acpi_device * instead, but
111  * for now, it's more convenient to operate on an acpi_handle.
112  */
113 int acpi_is_root_bridge(acpi_handle handle)
114 {
115         int ret;
116         struct acpi_device *device;
117
118         ret = acpi_bus_get_device(handle, &device);
119         if (ret)
120                 return 0;
121
122         ret = acpi_match_device_ids(device, root_device_ids);
123         if (ret)
124                 return 0;
125         else
126                 return 1;
127 }
128 EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
129
130 static acpi_status
131 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
132 {
133         struct resource *res = data;
134         struct acpi_resource_address64 address;
135
136         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
137             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
138             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
139                 return AE_OK;
140
141         acpi_resource_to_address64(resource, &address);
142         if ((address.address_length > 0) &&
143             (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
144                 res->start = address.minimum;
145                 res->end = address.minimum + address.address_length - 1;
146         }
147
148         return AE_OK;
149 }
150
151 static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
152                                              struct resource *res)
153 {
154         acpi_status status;
155
156         res->start = -1;
157         status =
158             acpi_walk_resources(handle, METHOD_NAME__CRS,
159                                 get_root_bridge_busnr_callback, res);
160         if (ACPI_FAILURE(status))
161                 return status;
162         if (res->start == -1)
163                 return AE_ERROR;
164         return AE_OK;
165 }
166
167 static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
168
169 static acpi_status acpi_pci_run_osc(acpi_handle handle,
170                                     const u32 *capbuf, u32 *retval)
171 {
172         struct acpi_osc_context context = {
173                 .uuid_str = pci_osc_uuid_str,
174                 .rev = 1,
175                 .cap.length = 12,
176                 .cap.pointer = (void *)capbuf,
177         };
178         acpi_status status;
179
180         status = acpi_run_osc(handle, &context);
181         if (ACPI_SUCCESS(status)) {
182                 *retval = *((u32 *)(context.ret.pointer + 8));
183                 kfree(context.ret.pointer);
184         }
185         return status;
186 }
187
188 static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
189                                         u32 support,
190                                         u32 *control)
191 {
192         acpi_status status;
193         u32 result, capbuf[3];
194
195         support &= OSC_PCI_SUPPORT_MASKS;
196         support |= root->osc_support_set;
197
198         capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
199         capbuf[OSC_SUPPORT_TYPE] = support;
200         if (control) {
201                 *control &= OSC_PCI_CONTROL_MASKS;
202                 capbuf[OSC_CONTROL_TYPE] = *control | root->osc_control_set;
203         } else {
204                 /* Run _OSC query for all possible controls. */
205                 capbuf[OSC_CONTROL_TYPE] = OSC_PCI_CONTROL_MASKS;
206         }
207
208         status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
209         if (ACPI_SUCCESS(status)) {
210                 root->osc_support_set = support;
211                 if (control)
212                         *control = result;
213         }
214         return status;
215 }
216
217 static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
218 {
219         acpi_status status;
220         acpi_handle tmp;
221
222         status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
223         if (ACPI_FAILURE(status))
224                 return status;
225         mutex_lock(&osc_lock);
226         status = acpi_pci_query_osc(root, flags, NULL);
227         mutex_unlock(&osc_lock);
228         return status;
229 }
230
231 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
232 {
233         struct acpi_pci_root *root;
234         struct acpi_device *device;
235
236         if (acpi_bus_get_device(handle, &device) ||
237             acpi_match_device_ids(device, root_device_ids))
238                 return NULL;
239
240         root = acpi_driver_data(device);
241
242         return root;
243 }
244 EXPORT_SYMBOL_GPL(acpi_pci_find_root);
245
246 struct acpi_handle_node {
247         struct list_head node;
248         acpi_handle handle;
249 };
250
251 /**
252  * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
253  * @handle: the handle in question
254  *
255  * Given an ACPI CA handle, the desired PCI device is located in the
256  * list of PCI devices.
257  *
258  * If the device is found, its reference count is increased and this
259  * function returns a pointer to its data structure.  The caller must
260  * decrement the reference count by calling pci_dev_put().
261  * If no device is found, %NULL is returned.
262  */
263 struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
264 {
265         int dev, fn;
266         unsigned long long adr;
267         acpi_status status;
268         acpi_handle phandle;
269         struct pci_bus *pbus;
270         struct pci_dev *pdev = NULL;
271         struct acpi_handle_node *node, *tmp;
272         struct acpi_pci_root *root;
273         LIST_HEAD(device_list);
274
275         /*
276          * Walk up the ACPI CA namespace until we reach a PCI root bridge.
277          */
278         phandle = handle;
279         while (!acpi_is_root_bridge(phandle)) {
280                 node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
281                 if (!node)
282                         goto out;
283
284                 INIT_LIST_HEAD(&node->node);
285                 node->handle = phandle;
286                 list_add(&node->node, &device_list);
287
288                 status = acpi_get_parent(phandle, &phandle);
289                 if (ACPI_FAILURE(status))
290                         goto out;
291         }
292
293         root = acpi_pci_find_root(phandle);
294         if (!root)
295                 goto out;
296
297         pbus = root->bus;
298
299         /*
300          * Now, walk back down the PCI device tree until we return to our
301          * original handle. Assumes that everything between the PCI root
302          * bridge and the device we're looking for must be a P2P bridge.
303          */
304         list_for_each_entry(node, &device_list, node) {
305                 acpi_handle hnd = node->handle;
306                 status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
307                 if (ACPI_FAILURE(status))
308                         goto out;
309                 dev = (adr >> 16) & 0xffff;
310                 fn  = adr & 0xffff;
311
312                 pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
313                 if (!pdev || hnd == handle)
314                         break;
315
316                 pbus = pdev->subordinate;
317                 pci_dev_put(pdev);
318
319                 /*
320                  * This function may be called for a non-PCI device that has a
321                  * PCI parent (eg. a disk under a PCI SATA controller).  In that
322                  * case pdev->subordinate will be NULL for the parent.
323                  */
324                 if (!pbus) {
325                         dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
326                         pdev = NULL;
327                         break;
328                 }
329         }
330 out:
331         list_for_each_entry_safe(node, tmp, &device_list, node)
332                 kfree(node);
333
334         return pdev;
335 }
336 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
337
338 /**
339  * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
340  * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
341  * @mask: Mask of _OSC bits to request control of, place to store control mask.
342  * @req: Mask of _OSC bits the control of is essential to the caller.
343  *
344  * Run _OSC query for @mask and if that is successful, compare the returned
345  * mask of control bits with @req.  If all of the @req bits are set in the
346  * returned mask, run _OSC request for it.
347  *
348  * The variable at the @mask address may be modified regardless of whether or
349  * not the function returns success.  On success it will contain the mask of
350  * _OSC bits the BIOS has granted control of, but its contents are meaningless
351  * on failure.
352  **/
353 acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
354 {
355         struct acpi_pci_root *root;
356         acpi_status status;
357         u32 ctrl, capbuf[3];
358         acpi_handle tmp;
359
360         if (!mask)
361                 return AE_BAD_PARAMETER;
362
363         ctrl = *mask & OSC_PCI_CONTROL_MASKS;
364         if ((ctrl & req) != req)
365                 return AE_TYPE;
366
367         root = acpi_pci_find_root(handle);
368         if (!root)
369                 return AE_NOT_EXIST;
370
371         status = acpi_get_handle(handle, "_OSC", &tmp);
372         if (ACPI_FAILURE(status))
373                 return status;
374
375         mutex_lock(&osc_lock);
376
377         *mask = ctrl | root->osc_control_set;
378         /* No need to evaluate _OSC if the control was already granted. */
379         if ((root->osc_control_set & ctrl) == ctrl)
380                 goto out;
381
382         /* Need to check the available controls bits before requesting them. */
383         while (*mask) {
384                 status = acpi_pci_query_osc(root, root->osc_support_set, mask);
385                 if (ACPI_FAILURE(status))
386                         goto out;
387                 if (ctrl == *mask)
388                         break;
389                 ctrl = *mask;
390         }
391
392         if ((ctrl & req) != req) {
393                 status = AE_SUPPORT;
394                 goto out;
395         }
396
397         capbuf[OSC_QUERY_TYPE] = 0;
398         capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
399         capbuf[OSC_CONTROL_TYPE] = ctrl;
400         status = acpi_pci_run_osc(handle, capbuf, mask);
401         if (ACPI_SUCCESS(status))
402                 root->osc_control_set = *mask;
403 out:
404         mutex_unlock(&osc_lock);
405         return status;
406 }
407 EXPORT_SYMBOL(acpi_pci_osc_control_set);
408
409 static int acpi_pci_root_add(struct acpi_device *device,
410                              const struct acpi_device_id *not_used)
411 {
412         unsigned long long segment, bus;
413         acpi_status status;
414         int result;
415         struct acpi_pci_root *root;
416         struct acpi_pci_driver *driver;
417         u32 flags, base_flags;
418
419         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
420         if (!root)
421                 return -ENOMEM;
422
423         segment = 0;
424         status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
425                                        &segment);
426         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
427                 printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
428                 result = -ENODEV;
429                 goto end;
430         }
431
432         /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
433         root->secondary.flags = IORESOURCE_BUS;
434         status = try_get_root_bridge_busnr(device->handle, &root->secondary);
435         if (ACPI_FAILURE(status)) {
436                 /*
437                  * We need both the start and end of the downstream bus range
438                  * to interpret _CBA (MMCONFIG base address), so it really is
439                  * supposed to be in _CRS.  If we don't find it there, all we
440                  * can do is assume [_BBN-0xFF] or [0-0xFF].
441                  */
442                 root->secondary.end = 0xFF;
443                 printk(KERN_WARNING FW_BUG PREFIX
444                        "no secondary bus range in _CRS\n");
445                 status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,
446                                                NULL, &bus);
447                 if (ACPI_SUCCESS(status))
448                         root->secondary.start = bus;
449                 else if (status == AE_NOT_FOUND)
450                         root->secondary.start = 0;
451                 else {
452                         printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
453                         result = -ENODEV;
454                         goto end;
455                 }
456         }
457
458         INIT_LIST_HEAD(&root->node);
459         root->device = device;
460         root->segment = segment & 0xFFFF;
461         strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
462         strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
463         device->driver_data = root;
464
465         printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
466                acpi_device_name(device), acpi_device_bid(device),
467                root->segment, &root->secondary);
468
469         root->mcfg_addr = acpi_pci_root_get_mcfg_addr(device->handle);
470
471         /*
472          * All supported architectures that use ACPI have support for
473          * PCI domains, so we indicate this in _OSC support capabilities.
474          */
475         flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
476         acpi_pci_osc_support(root, flags);
477
478         /*
479          * TBD: Need PCI interface for enumeration/configuration of roots.
480          */
481
482         mutex_lock(&acpi_pci_root_lock);
483         list_add_tail(&root->node, &acpi_pci_roots);
484         mutex_unlock(&acpi_pci_root_lock);
485
486         /*
487          * Scan the Root Bridge
488          * --------------------
489          * Must do this prior to any attempt to bind the root device, as the
490          * PCI namespace does not get created until this call is made (and
491          * thus the root bridge's pci_dev does not exist).
492          */
493         root->bus = pci_acpi_scan_root(root);
494         if (!root->bus) {
495                 printk(KERN_ERR PREFIX
496                             "Bus %04x:%02x not present in PCI namespace\n",
497                             root->segment, (unsigned int)root->secondary.start);
498                 result = -ENODEV;
499                 goto out_del_root;
500         }
501
502         /* Indicate support for various _OSC capabilities. */
503         if (pci_ext_cfg_avail())
504                 flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
505         if (pcie_aspm_support_enabled()) {
506                 flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
507                 OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
508         }
509         if (pci_msi_enabled())
510                 flags |= OSC_MSI_SUPPORT;
511         if (flags != base_flags) {
512                 status = acpi_pci_osc_support(root, flags);
513                 if (ACPI_FAILURE(status)) {
514                         dev_info(&device->dev, "ACPI _OSC support "
515                                 "notification failed, disabling PCIe ASPM\n");
516                         pcie_no_aspm();
517                         flags = base_flags;
518                 }
519         }
520
521         if (!pcie_ports_disabled
522             && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) {
523                 flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
524                         | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
525                         | OSC_PCI_EXPRESS_PME_CONTROL;
526
527                 if (pci_aer_available()) {
528                         if (aer_acpi_firmware_first())
529                                 dev_dbg(&device->dev,
530                                         "PCIe errors handled by BIOS.\n");
531                         else
532                                 flags |= OSC_PCI_EXPRESS_AER_CONTROL;
533                 }
534
535                 dev_info(&device->dev,
536                         "Requesting ACPI _OSC control (0x%02x)\n", flags);
537
538                 status = acpi_pci_osc_control_set(device->handle, &flags,
539                                        OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
540                 if (ACPI_SUCCESS(status)) {
541                         dev_info(&device->dev,
542                                 "ACPI _OSC control (0x%02x) granted\n", flags);
543                         if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
544                                 /*
545                                  * We have ASPM control, but the FADT indicates
546                                  * that it's unsupported. Clear it.
547                                  */
548                                 pcie_clear_aspm(root->bus);
549                         }
550                 } else {
551                         dev_info(&device->dev,
552                                 "ACPI _OSC request failed (%s), "
553                                 "returned control mask: 0x%02x\n",
554                                 acpi_format_exception(status), flags);
555                         pr_info("ACPI _OSC control for PCIe not granted, "
556                                 "disabling ASPM\n");
557                         pcie_no_aspm();
558                 }
559         } else {
560                 dev_info(&device->dev,
561                          "Unable to request _OSC control "
562                          "(_OSC support mask: 0x%02x)\n", flags);
563         }
564
565         pci_acpi_add_bus_pm_notifier(device, root->bus);
566         if (device->wakeup.flags.run_wake)
567                 device_set_run_wake(root->bus->bridge, true);
568
569         if (system_state != SYSTEM_BOOTING) {
570                 pcibios_resource_survey_bus(root->bus);
571                 pci_assign_unassigned_bus_resources(root->bus);
572         }
573
574         mutex_lock(&acpi_pci_root_lock);
575         list_for_each_entry(driver, &acpi_pci_drivers, node)
576                 if (driver->add)
577                         driver->add(root);
578         mutex_unlock(&acpi_pci_root_lock);
579
580         /* need to after hot-added ioapic is registered */
581         if (system_state != SYSTEM_BOOTING)
582                 pci_enable_bridges(root->bus);
583
584         pci_bus_add_devices(root->bus);
585         return 1;
586
587 out_del_root:
588         mutex_lock(&acpi_pci_root_lock);
589         list_del(&root->node);
590         mutex_unlock(&acpi_pci_root_lock);
591
592 end:
593         kfree(root);
594         return result;
595 }
596
597 static void acpi_pci_root_remove(struct acpi_device *device)
598 {
599         struct acpi_pci_root *root = acpi_driver_data(device);
600         struct acpi_pci_driver *driver;
601
602         pci_stop_root_bus(root->bus);
603
604         mutex_lock(&acpi_pci_root_lock);
605         list_for_each_entry_reverse(driver, &acpi_pci_drivers, node)
606                 if (driver->remove)
607                         driver->remove(root);
608         mutex_unlock(&acpi_pci_root_lock);
609
610         device_set_run_wake(root->bus->bridge, false);
611         pci_acpi_remove_bus_pm_notifier(device);
612
613         pci_remove_root_bus(root->bus);
614
615         mutex_lock(&acpi_pci_root_lock);
616         list_del(&root->node);
617         mutex_unlock(&acpi_pci_root_lock);
618         kfree(root);
619 }
620
621 void __init acpi_pci_root_init(void)
622 {
623         acpi_hest_init();
624
625         if (!acpi_pci_disabled) {
626                 pci_acpi_crs_quirks();
627                 acpi_scan_add_handler(&pci_root_handler);
628         }
629 }
630 /* Support root bridge hotplug */
631
632 static void handle_root_bridge_insertion(acpi_handle handle)
633 {
634         struct acpi_device *device;
635
636         if (!acpi_bus_get_device(handle, &device)) {
637                 printk(KERN_DEBUG "acpi device exists...\n");
638                 return;
639         }
640
641         if (acpi_bus_scan(handle))
642                 printk(KERN_ERR "cannot add bridge to acpi list\n");
643 }
644
645 static void handle_root_bridge_removal(struct acpi_device *device)
646 {
647         acpi_status status;
648         struct acpi_eject_event *ej_event;
649
650         ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
651         if (!ej_event) {
652                 /* Inform firmware the hot-remove operation has error */
653                 (void) acpi_evaluate_hotplug_ost(device->handle,
654                                         ACPI_NOTIFY_EJECT_REQUEST,
655                                         ACPI_OST_SC_NON_SPECIFIC_FAILURE,
656                                         NULL);
657                 return;
658         }
659
660         ej_event->device = device;
661         ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
662
663         status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, ej_event);
664         if (ACPI_FAILURE(status))
665                 kfree(ej_event);
666 }
667
668 static void _handle_hotplug_event_root(struct work_struct *work)
669 {
670         struct acpi_pci_root *root;
671         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER };
672         struct acpi_hp_work *hp_work;
673         acpi_handle handle;
674         u32 type;
675
676         hp_work = container_of(work, struct acpi_hp_work, work);
677         handle = hp_work->handle;
678         type = hp_work->type;
679
680         acpi_scan_lock_acquire();
681
682         root = acpi_pci_find_root(handle);
683         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
684
685         switch (type) {
686         case ACPI_NOTIFY_BUS_CHECK:
687                 /* bus enumerate */
688                 printk(KERN_DEBUG "%s: Bus check notify on %s\n", __func__,
689                                  (char *)buffer.pointer);
690                 if (!root)
691                         handle_root_bridge_insertion(handle);
692
693                 break;
694
695         case ACPI_NOTIFY_DEVICE_CHECK:
696                 /* device check */
697                 printk(KERN_DEBUG "%s: Device check notify on %s\n", __func__,
698                                  (char *)buffer.pointer);
699                 if (!root)
700                         handle_root_bridge_insertion(handle);
701                 break;
702
703         case ACPI_NOTIFY_EJECT_REQUEST:
704                 /* request device eject */
705                 printk(KERN_DEBUG "%s: Device eject notify on %s\n", __func__,
706                                  (char *)buffer.pointer);
707                 if (root)
708                         handle_root_bridge_removal(root->device);
709                 break;
710         default:
711                 printk(KERN_WARNING "notify_handler: unknown event type 0x%x for %s\n",
712                                  type, (char *)buffer.pointer);
713                 break;
714         }
715
716         acpi_scan_lock_release();
717         kfree(hp_work); /* allocated in handle_hotplug_event_bridge */
718         kfree(buffer.pointer);
719 }
720
721 static void handle_hotplug_event_root(acpi_handle handle, u32 type,
722                                         void *context)
723 {
724         alloc_acpi_hp_work(handle, type, context,
725                                 _handle_hotplug_event_root);
726 }
727
728 static acpi_status __init
729 find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
730 {
731         acpi_status status;
732         char objname[64];
733         struct acpi_buffer buffer = { .length = sizeof(objname),
734                                       .pointer = objname };
735         int *count = (int *)context;
736
737         if (!acpi_is_root_bridge(handle))
738                 return AE_OK;
739
740         (*count)++;
741
742         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
743
744         status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
745                                         handle_hotplug_event_root, NULL);
746         if (ACPI_FAILURE(status))
747                 printk(KERN_DEBUG "acpi root: %s notify handler is not installed, exit status: %u\n",
748                                   objname, (unsigned int)status);
749         else
750                 printk(KERN_DEBUG "acpi root: %s notify handler is installed\n",
751                                  objname);
752
753         return AE_OK;
754 }
755
756 void __init acpi_pci_root_hp_init(void)
757 {
758         int num = 0;
759
760         acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
761                 ACPI_UINT32_MAX, find_root_bridges, NULL, &num, NULL);
762
763         printk(KERN_DEBUG "Found %d acpi root devices\n", num);
764 }