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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * ACPI PCI HotPlug glue functions to ACPI CA subsystem
4 *
5 * Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com)
6 * Copyright (C) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com)
7 * Copyright (C) 2002,2003 NEC Corporation
8 * Copyright (C) 2003-2005 Matthew Wilcox (willy@infradead.org)
9 * Copyright (C) 2003-2005 Hewlett Packard
10 * Copyright (C) 2005 Rajesh Shah (rajesh.shah@intel.com)
11 * Copyright (C) 2005 Intel Corporation
12 *
13 * All rights reserved.
14 *
15 * Send feedback to <kristen.c.accardi@intel.com>
16 *
17 */
18
19/*
20 * Lifetime rules for pci_dev:
21 * - The one in acpiphp_bridge has its refcount elevated by pci_get_slot()
22 * when the bridge is scanned and it loses a refcount when the bridge
23 * is removed.
24 * - When a P2P bridge is present, we elevate the refcount on the subordinate
25 * bus. It loses the refcount when the the driver unloads.
26 */
27
28#define pr_fmt(fmt) "acpiphp_glue: " fmt
29
30#include <linux/module.h>
31
32#include <linux/kernel.h>
33#include <linux/pci.h>
34#include <linux/pci_hotplug.h>
35#include <linux/pci-acpi.h>
36#include <linux/pm_runtime.h>
37#include <linux/mutex.h>
38#include <linux/slab.h>
39#include <linux/acpi.h>
40
41#include "../pci.h"
42#include "acpiphp.h"
43
44static LIST_HEAD(bridge_list);
45static DEFINE_MUTEX(bridge_mutex);
46
47static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type);
48static void acpiphp_post_dock_fixup(struct acpi_device *adev);
49static void acpiphp_sanitize_bus(struct pci_bus *bus);
50static void hotplug_event(u32 type, struct acpiphp_context *context);
51static void free_bridge(struct kref *kref);
52
53/**
54 * acpiphp_init_context - Create hotplug context and grab a reference to it.
55 * @adev: ACPI device object to create the context for.
56 *
57 * Call under acpi_hp_context_lock.
58 */
59static struct acpiphp_context *acpiphp_init_context(struct acpi_device *adev)
60{
61 struct acpiphp_context *context;
62
63 context = kzalloc(sizeof(*context), GFP_KERNEL);
64 if (!context)
65 return NULL;
66
67 context->refcount = 1;
68 context->hp.notify = acpiphp_hotplug_notify;
69 context->hp.fixup = acpiphp_post_dock_fixup;
70 acpi_set_hp_context(adev, &context->hp);
71 return context;
72}
73
74/**
75 * acpiphp_get_context - Get hotplug context and grab a reference to it.
76 * @adev: ACPI device object to get the context for.
77 *
78 * Call under acpi_hp_context_lock.
79 */
80static struct acpiphp_context *acpiphp_get_context(struct acpi_device *adev)
81{
82 struct acpiphp_context *context;
83
84 if (!adev->hp)
85 return NULL;
86
87 context = to_acpiphp_context(adev->hp);
88 context->refcount++;
89 return context;
90}
91
92/**
93 * acpiphp_put_context - Drop a reference to ACPI hotplug context.
94 * @context: ACPI hotplug context to drop a reference to.
95 *
96 * The context object is removed if there are no more references to it.
97 *
98 * Call under acpi_hp_context_lock.
99 */
100static void acpiphp_put_context(struct acpiphp_context *context)
101{
102 if (--context->refcount)
103 return;
104
105 WARN_ON(context->bridge);
106 context->hp.self->hp = NULL;
107 kfree(context);
108}
109
110static inline void get_bridge(struct acpiphp_bridge *bridge)
111{
112 kref_get(&bridge->ref);
113}
114
115static inline void put_bridge(struct acpiphp_bridge *bridge)
116{
117 kref_put(&bridge->ref, free_bridge);
118}
119
120static struct acpiphp_context *acpiphp_grab_context(struct acpi_device *adev)
121{
122 struct acpiphp_context *context;
123
124 acpi_lock_hp_context();
125 context = acpiphp_get_context(adev);
126 if (!context || context->func.parent->is_going_away) {
127 acpi_unlock_hp_context();
128 return NULL;
129 }
130 get_bridge(context->func.parent);
131 acpiphp_put_context(context);
132 acpi_unlock_hp_context();
133 return context;
134}
135
136static void acpiphp_let_context_go(struct acpiphp_context *context)
137{
138 put_bridge(context->func.parent);
139}
140
141static void free_bridge(struct kref *kref)
142{
143 struct acpiphp_context *context;
144 struct acpiphp_bridge *bridge;
145 struct acpiphp_slot *slot, *next;
146 struct acpiphp_func *func, *tmp;
147
148 acpi_lock_hp_context();
149
150 bridge = container_of(kref, struct acpiphp_bridge, ref);
151
152 list_for_each_entry_safe(slot, next, &bridge->slots, node) {
153 list_for_each_entry_safe(func, tmp, &slot->funcs, sibling)
154 acpiphp_put_context(func_to_context(func));
155
156 kfree(slot);
157 }
158
159 context = bridge->context;
160 /* Root bridges will not have hotplug context. */
161 if (context) {
162 /* Release the reference taken by acpiphp_enumerate_slots(). */
163 put_bridge(context->func.parent);
164 context->bridge = NULL;
165 acpiphp_put_context(context);
166 }
167
168 put_device(&bridge->pci_bus->dev);
169 pci_dev_put(bridge->pci_dev);
170 kfree(bridge);
171
172 acpi_unlock_hp_context();
173}
174
175/**
176 * acpiphp_post_dock_fixup - Post-dock fixups for PCI devices.
177 * @adev: ACPI device object corresponding to a PCI device.
178 *
179 * TBD - figure out a way to only call fixups for systems that require them.
180 */
181static void acpiphp_post_dock_fixup(struct acpi_device *adev)
182{
183 struct acpiphp_context *context = acpiphp_grab_context(adev);
184 struct pci_bus *bus;
185 u32 buses;
186
187 if (!context)
188 return;
189
190 bus = context->func.slot->bus;
191 if (!bus->self)
192 goto out;
193
194 /* fixup bad _DCK function that rewrites
195 * secondary bridge on slot
196 */
197 pci_read_config_dword(bus->self, PCI_PRIMARY_BUS, &buses);
198
199 if (((buses >> 8) & 0xff) != bus->busn_res.start) {
200 buses = (buses & 0xff000000)
201 | ((unsigned int)(bus->primary) << 0)
202 | ((unsigned int)(bus->busn_res.start) << 8)
203 | ((unsigned int)(bus->busn_res.end) << 16);
204 pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
205 }
206
207 out:
208 acpiphp_let_context_go(context);
209}
210
211/**
212 * acpiphp_add_context - Add ACPIPHP context to an ACPI device object.
213 * @handle: ACPI handle of the object to add a context to.
214 * @lvl: Not used.
215 * @data: The object's parent ACPIPHP bridge.
216 * @rv: Not used.
217 */
218static acpi_status acpiphp_add_context(acpi_handle handle, u32 lvl, void *data,
219 void **rv)
220{
221 struct acpiphp_bridge *bridge = data;
222 struct acpiphp_context *context;
223 struct acpi_device *adev;
224 struct acpiphp_slot *slot;
225 struct acpiphp_func *newfunc;
226 acpi_status status = AE_OK;
227 unsigned long long adr;
228 int device, function;
229 struct pci_bus *pbus = bridge->pci_bus;
230 struct pci_dev *pdev = bridge->pci_dev;
231 u32 val;
232
233 status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
234 if (ACPI_FAILURE(status)) {
235 if (status != AE_NOT_FOUND)
236 acpi_handle_warn(handle,
237 "can't evaluate _ADR (%#x)\n", status);
238 return AE_OK;
239 }
240 if (acpi_bus_get_device(handle, &adev))
241 return AE_OK;
242
243 device = (adr >> 16) & 0xffff;
244 function = adr & 0xffff;
245
246 acpi_lock_hp_context();
247 context = acpiphp_init_context(adev);
248 if (!context) {
249 acpi_unlock_hp_context();
250 acpi_handle_err(handle, "No hotplug context\n");
251 return AE_NOT_EXIST;
252 }
253 newfunc = &context->func;
254 newfunc->function = function;
255 newfunc->parent = bridge;
256 acpi_unlock_hp_context();
257
258 /*
259 * If this is a dock device, its _EJ0 should be executed by the dock
260 * notify handler after calling _DCK.
261 */
262 if (!is_dock_device(adev) && acpi_has_method(handle, "_EJ0"))
263 newfunc->flags = FUNC_HAS_EJ0;
264
265 if (acpi_has_method(handle, "_STA"))
266 newfunc->flags |= FUNC_HAS_STA;
267
268 /* search for objects that share the same slot */
269 list_for_each_entry(slot, &bridge->slots, node)
270 if (slot->device == device)
271 goto slot_found;
272
273 slot = kzalloc(sizeof(struct acpiphp_slot), GFP_KERNEL);
274 if (!slot) {
275 acpi_lock_hp_context();
276 acpiphp_put_context(context);
277 acpi_unlock_hp_context();
278 return AE_NO_MEMORY;
279 }
280
281 slot->bus = bridge->pci_bus;
282 slot->device = device;
283 INIT_LIST_HEAD(&slot->funcs);
284
285 list_add_tail(&slot->node, &bridge->slots);
286
287 /*
288 * Expose slots to user space for functions that have _EJ0 or _RMV or
289 * are located in dock stations. Do not expose them for devices handled
290 * by the native PCIe hotplug (PCIeHP) or standard PCI hotplug
291 * (SHPCHP), because that code is supposed to expose slots to user
292 * space in those cases.
293 */
294 if ((acpi_pci_check_ejectable(pbus, handle) || is_dock_device(adev))
295 && !(pdev && hotplug_is_native(pdev))) {
296 unsigned long long sun;
297 int retval;
298
299 bridge->nr_slots++;
300 status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
301 if (ACPI_FAILURE(status))
302 sun = bridge->nr_slots;
303
304 pr_debug("found ACPI PCI Hotplug slot %llu at PCI %04x:%02x:%02x\n",
305 sun, pci_domain_nr(pbus), pbus->number, device);
306
307 retval = acpiphp_register_hotplug_slot(slot, sun);
308 if (retval) {
309 slot->slot = NULL;
310 bridge->nr_slots--;
311 if (retval == -EBUSY)
312 pr_warn("Slot %llu already registered by another hotplug driver\n", sun);
313 else
314 pr_warn("acpiphp_register_hotplug_slot failed (err code = 0x%x)\n", retval);
315 }
316 /* Even if the slot registration fails, we can still use it. */
317 }
318
319 slot_found:
320 newfunc->slot = slot;
321 list_add_tail(&newfunc->sibling, &slot->funcs);
322
323 if (pci_bus_read_dev_vendor_id(pbus, PCI_DEVFN(device, function),
324 &val, 60*1000))
325 slot->flags |= SLOT_ENABLED;
326
327 return AE_OK;
328}
329
330static void cleanup_bridge(struct acpiphp_bridge *bridge)
331{
332 struct acpiphp_slot *slot;
333 struct acpiphp_func *func;
334
335 list_for_each_entry(slot, &bridge->slots, node) {
336 list_for_each_entry(func, &slot->funcs, sibling) {
337 struct acpi_device *adev = func_to_acpi_device(func);
338
339 acpi_lock_hp_context();
340 adev->hp->notify = NULL;
341 adev->hp->fixup = NULL;
342 acpi_unlock_hp_context();
343 }
344 slot->flags |= SLOT_IS_GOING_AWAY;
345 if (slot->slot)
346 acpiphp_unregister_hotplug_slot(slot);
347 }
348
349 mutex_lock(&bridge_mutex);
350 list_del(&bridge->list);
351 mutex_unlock(&bridge_mutex);
352
353 acpi_lock_hp_context();
354 bridge->is_going_away = true;
355 acpi_unlock_hp_context();
356}
357
358/**
359 * acpiphp_max_busnr - return the highest reserved bus number under the given bus.
360 * @bus: bus to start search with
361 */
362static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
363{
364 struct pci_bus *tmp;
365 unsigned char max, n;
366
367 /*
368 * pci_bus_max_busnr will return the highest
369 * reserved busnr for all these children.
370 * that is equivalent to the bus->subordinate
371 * value. We don't want to use the parent's
372 * bus->subordinate value because it could have
373 * padding in it.
374 */
375 max = bus->busn_res.start;
376
377 list_for_each_entry(tmp, &bus->children, node) {
378 n = pci_bus_max_busnr(tmp);
379 if (n > max)
380 max = n;
381 }
382 return max;
383}
384
385static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
386{
387 struct acpiphp_func *func;
388 union acpi_object params[2];
389 struct acpi_object_list arg_list;
390
391 list_for_each_entry(func, &slot->funcs, sibling) {
392 arg_list.count = 2;
393 arg_list.pointer = params;
394 params[0].type = ACPI_TYPE_INTEGER;
395 params[0].integer.value = ACPI_ADR_SPACE_PCI_CONFIG;
396 params[1].type = ACPI_TYPE_INTEGER;
397 params[1].integer.value = 1;
398 /* _REG is optional, we don't care about if there is failure */
399 acpi_evaluate_object(func_to_handle(func), "_REG", &arg_list,
400 NULL);
401 }
402}
403
404static void check_hotplug_bridge(struct acpiphp_slot *slot, struct pci_dev *dev)
405{
406 struct acpiphp_func *func;
407
408 /* quirk, or pcie could set it already */
409 if (dev->is_hotplug_bridge)
410 return;
411
412 list_for_each_entry(func, &slot->funcs, sibling) {
413 if (PCI_FUNC(dev->devfn) == func->function) {
414 dev->is_hotplug_bridge = 1;
415 break;
416 }
417 }
418}
419
420static int acpiphp_rescan_slot(struct acpiphp_slot *slot)
421{
422 struct acpiphp_func *func;
423
424 list_for_each_entry(func, &slot->funcs, sibling) {
425 struct acpi_device *adev = func_to_acpi_device(func);
426
427 acpi_bus_scan(adev->handle);
428 if (acpi_device_enumerated(adev))
429 acpi_device_set_power(adev, ACPI_STATE_D0);
430 }
431 return pci_scan_slot(slot->bus, PCI_DEVFN(slot->device, 0));
432}
433
434static void acpiphp_native_scan_bridge(struct pci_dev *bridge)
435{
436 struct pci_bus *bus = bridge->subordinate;
437 struct pci_dev *dev;
438 int max;
439
440 if (!bus)
441 return;
442
443 max = bus->busn_res.start;
444 /* Scan already configured non-hotplug bridges */
445 for_each_pci_bridge(dev, bus) {
446 if (!hotplug_is_native(dev))
447 max = pci_scan_bridge(bus, dev, max, 0);
448 }
449
450 /* Scan non-hotplug bridges that need to be reconfigured */
451 for_each_pci_bridge(dev, bus) {
452 if (!hotplug_is_native(dev))
453 max = pci_scan_bridge(bus, dev, max, 1);
454 }
455}
456
457/**
458 * enable_slot - enable, configure a slot
459 * @slot: slot to be enabled
460 * @bridge: true if enable is for the whole bridge (not a single slot)
461 *
462 * This function should be called per *physical slot*,
463 * not per each slot object in ACPI namespace.
464 */
465static void enable_slot(struct acpiphp_slot *slot, bool bridge)
466{
467 struct pci_dev *dev;
468 struct pci_bus *bus = slot->bus;
469 struct acpiphp_func *func;
470
471 if (bridge && bus->self && hotplug_is_native(bus->self)) {
472 /*
473 * If native hotplug is used, it will take care of hotplug
474 * slot management and resource allocation for hotplug
475 * bridges. However, ACPI hotplug may still be used for
476 * non-hotplug bridges to bring in additional devices such
477 * as a Thunderbolt host controller.
478 */
479 for_each_pci_bridge(dev, bus) {
480 if (PCI_SLOT(dev->devfn) == slot->device)
481 acpiphp_native_scan_bridge(dev);
482 }
483 pci_assign_unassigned_bridge_resources(bus->self);
484 } else {
485 LIST_HEAD(add_list);
486 int max, pass;
487
488 acpiphp_rescan_slot(slot);
489 max = acpiphp_max_busnr(bus);
490 for (pass = 0; pass < 2; pass++) {
491 for_each_pci_bridge(dev, bus) {
492 if (PCI_SLOT(dev->devfn) != slot->device)
493 continue;
494
495 max = pci_scan_bridge(bus, dev, max, pass);
496 if (pass && dev->subordinate) {
497 check_hotplug_bridge(slot, dev);
498 pcibios_resource_survey_bus(dev->subordinate);
499 __pci_bus_size_bridges(dev->subordinate,
500 &add_list);
501 }
502 }
503 }
504 __pci_bus_assign_resources(bus, &add_list, NULL);
505 }
506
507 acpiphp_sanitize_bus(bus);
508 pcie_bus_configure_settings(bus);
509 acpiphp_set_acpi_region(slot);
510
511 list_for_each_entry(dev, &bus->devices, bus_list) {
512 /* Assume that newly added devices are powered on already. */
513 if (!pci_dev_is_added(dev))
514 dev->current_state = PCI_D0;
515 }
516
517 pci_bus_add_devices(bus);
518
519 slot->flags |= SLOT_ENABLED;
520 list_for_each_entry(func, &slot->funcs, sibling) {
521 dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
522 func->function));
523 if (!dev) {
524 /* Do not set SLOT_ENABLED flag if some funcs
525 are not added. */
526 slot->flags &= ~SLOT_ENABLED;
527 continue;
528 }
529 }
530}
531
532/**
533 * disable_slot - disable a slot
534 * @slot: ACPI PHP slot
535 */
536static void disable_slot(struct acpiphp_slot *slot)
537{
538 struct pci_bus *bus = slot->bus;
539 struct pci_dev *dev, *prev;
540 struct acpiphp_func *func;
541
542 /*
543 * enable_slot() enumerates all functions in this device via
544 * pci_scan_slot(), whether they have associated ACPI hotplug
545 * methods (_EJ0, etc.) or not. Therefore, we remove all functions
546 * here.
547 */
548 list_for_each_entry_safe_reverse(dev, prev, &bus->devices, bus_list)
549 if (PCI_SLOT(dev->devfn) == slot->device)
550 pci_stop_and_remove_bus_device(dev);
551
552 list_for_each_entry(func, &slot->funcs, sibling)
553 acpi_bus_trim(func_to_acpi_device(func));
554
555 slot->flags &= ~SLOT_ENABLED;
556}
557
558static bool slot_no_hotplug(struct acpiphp_slot *slot)
559{
560 struct pci_bus *bus = slot->bus;
561 struct pci_dev *dev;
562
563 list_for_each_entry(dev, &bus->devices, bus_list) {
564 if (PCI_SLOT(dev->devfn) == slot->device && dev->ignore_hotplug)
565 return true;
566 }
567 return false;
568}
569
570/**
571 * get_slot_status - get ACPI slot status
572 * @slot: ACPI PHP slot
573 *
574 * If a slot has _STA for each function and if any one of them
575 * returned non-zero status, return it.
576 *
577 * If a slot doesn't have _STA and if any one of its functions'
578 * configuration space is configured, return 0x0f as a _STA.
579 *
580 * Otherwise return 0.
581 */
582static unsigned int get_slot_status(struct acpiphp_slot *slot)
583{
584 unsigned long long sta = 0;
585 struct acpiphp_func *func;
586 u32 dvid;
587
588 list_for_each_entry(func, &slot->funcs, sibling) {
589 if (func->flags & FUNC_HAS_STA) {
590 acpi_status status;
591
592 status = acpi_evaluate_integer(func_to_handle(func),
593 "_STA", NULL, &sta);
594 if (ACPI_SUCCESS(status) && sta)
595 break;
596 } else {
597 if (pci_bus_read_dev_vendor_id(slot->bus,
598 PCI_DEVFN(slot->device, func->function),
599 &dvid, 0)) {
600 sta = ACPI_STA_ALL;
601 break;
602 }
603 }
604 }
605
606 if (!sta) {
607 /*
608 * Check for the slot itself since it may be that the
609 * ACPI slot is a device below PCIe upstream port so in
610 * that case it may not even be reachable yet.
611 */
612 if (pci_bus_read_dev_vendor_id(slot->bus,
613 PCI_DEVFN(slot->device, 0), &dvid, 0)) {
614 sta = ACPI_STA_ALL;
615 }
616 }
617
618 return (unsigned int)sta;
619}
620
621static inline bool device_status_valid(unsigned int sta)
622{
623 /*
624 * ACPI spec says that _STA may return bit 0 clear with bit 3 set
625 * if the device is valid but does not require a device driver to be
626 * loaded (Section 6.3.7 of ACPI 5.0A).
627 */
628 unsigned int mask = ACPI_STA_DEVICE_ENABLED | ACPI_STA_DEVICE_FUNCTIONING;
629 return (sta & mask) == mask;
630}
631
632/**
633 * trim_stale_devices - remove PCI devices that are not responding.
634 * @dev: PCI device to start walking the hierarchy from.
635 */
636static void trim_stale_devices(struct pci_dev *dev)
637{
638 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
639 struct pci_bus *bus = dev->subordinate;
640 bool alive = dev->ignore_hotplug;
641
642 if (adev) {
643 acpi_status status;
644 unsigned long long sta;
645
646 status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
647 alive = alive || (ACPI_SUCCESS(status) && device_status_valid(sta));
648 }
649 if (!alive)
650 alive = pci_device_is_present(dev);
651
652 if (!alive) {
653 pci_dev_set_disconnected(dev, NULL);
654 if (pci_has_subordinate(dev))
655 pci_walk_bus(dev->subordinate, pci_dev_set_disconnected,
656 NULL);
657
658 pci_stop_and_remove_bus_device(dev);
659 if (adev)
660 acpi_bus_trim(adev);
661 } else if (bus) {
662 struct pci_dev *child, *tmp;
663
664 /* The device is a bridge. so check the bus below it. */
665 pm_runtime_get_sync(&dev->dev);
666 list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
667 trim_stale_devices(child);
668
669 pm_runtime_put(&dev->dev);
670 }
671}
672
673/**
674 * acpiphp_check_bridge - re-enumerate devices
675 * @bridge: where to begin re-enumeration
676 *
677 * Iterate over all slots under this bridge and make sure that if a
678 * card is present they are enabled, and if not they are disabled.
679 */
680static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
681{
682 struct acpiphp_slot *slot;
683
684 /* Bail out if the bridge is going away. */
685 if (bridge->is_going_away)
686 return;
687
688 if (bridge->pci_dev)
689 pm_runtime_get_sync(&bridge->pci_dev->dev);
690
691 list_for_each_entry(slot, &bridge->slots, node) {
692 struct pci_bus *bus = slot->bus;
693 struct pci_dev *dev, *tmp;
694
695 if (slot_no_hotplug(slot)) {
696 ; /* do nothing */
697 } else if (device_status_valid(get_slot_status(slot))) {
698 /* remove stale devices if any */
699 list_for_each_entry_safe_reverse(dev, tmp,
700 &bus->devices, bus_list)
701 if (PCI_SLOT(dev->devfn) == slot->device)
702 trim_stale_devices(dev);
703
704 /* configure all functions */
705 enable_slot(slot, true);
706 } else {
707 disable_slot(slot);
708 }
709 }
710
711 if (bridge->pci_dev)
712 pm_runtime_put(&bridge->pci_dev->dev);
713}
714
715/*
716 * Remove devices for which we could not assign resources, call
717 * arch specific code to fix-up the bus
718 */
719static void acpiphp_sanitize_bus(struct pci_bus *bus)
720{
721 struct pci_dev *dev, *tmp;
722 int i;
723 unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
724
725 list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
726 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
727 struct resource *res = &dev->resource[i];
728 if ((res->flags & type_mask) && !res->start &&
729 res->end) {
730 /* Could not assign a required resources
731 * for this device, remove it */
732 pci_stop_and_remove_bus_device(dev);
733 break;
734 }
735 }
736 }
737}
738
739/*
740 * ACPI event handlers
741 */
742
743void acpiphp_check_host_bridge(struct acpi_device *adev)
744{
745 struct acpiphp_bridge *bridge = NULL;
746
747 acpi_lock_hp_context();
748 if (adev->hp) {
749 bridge = to_acpiphp_root_context(adev->hp)->root_bridge;
750 if (bridge)
751 get_bridge(bridge);
752 }
753 acpi_unlock_hp_context();
754 if (bridge) {
755 pci_lock_rescan_remove();
756
757 acpiphp_check_bridge(bridge);
758
759 pci_unlock_rescan_remove();
760 put_bridge(bridge);
761 }
762}
763
764static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
765
766static void hotplug_event(u32 type, struct acpiphp_context *context)
767{
768 acpi_handle handle = context->hp.self->handle;
769 struct acpiphp_func *func = &context->func;
770 struct acpiphp_slot *slot = func->slot;
771 struct acpiphp_bridge *bridge;
772
773 acpi_lock_hp_context();
774 bridge = context->bridge;
775 if (bridge)
776 get_bridge(bridge);
777
778 acpi_unlock_hp_context();
779
780 pci_lock_rescan_remove();
781
782 switch (type) {
783 case ACPI_NOTIFY_BUS_CHECK:
784 /* bus re-enumerate */
785 acpi_handle_debug(handle, "Bus check in %s()\n", __func__);
786 if (bridge)
787 acpiphp_check_bridge(bridge);
788 else if (!(slot->flags & SLOT_IS_GOING_AWAY))
789 enable_slot(slot, false);
790
791 break;
792
793 case ACPI_NOTIFY_DEVICE_CHECK:
794 /* device check */
795 acpi_handle_debug(handle, "Device check in %s()\n", __func__);
796 if (bridge) {
797 acpiphp_check_bridge(bridge);
798 } else if (!(slot->flags & SLOT_IS_GOING_AWAY)) {
799 /*
800 * Check if anything has changed in the slot and rescan
801 * from the parent if that's the case.
802 */
803 if (acpiphp_rescan_slot(slot))
804 acpiphp_check_bridge(func->parent);
805 }
806 break;
807
808 case ACPI_NOTIFY_EJECT_REQUEST:
809 /* request device eject */
810 acpi_handle_debug(handle, "Eject request in %s()\n", __func__);
811 acpiphp_disable_and_eject_slot(slot);
812 break;
813 }
814
815 pci_unlock_rescan_remove();
816 if (bridge)
817 put_bridge(bridge);
818}
819
820static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type)
821{
822 struct acpiphp_context *context;
823
824 context = acpiphp_grab_context(adev);
825 if (!context)
826 return -ENODATA;
827
828 hotplug_event(type, context);
829 acpiphp_let_context_go(context);
830 return 0;
831}
832
833/**
834 * acpiphp_enumerate_slots - Enumerate PCI slots for a given bus.
835 * @bus: PCI bus to enumerate the slots for.
836 *
837 * A "slot" is an object associated with a PCI device number. All functions
838 * (PCI devices) with the same bus and device number belong to the same slot.
839 */
840void acpiphp_enumerate_slots(struct pci_bus *bus)
841{
842 struct acpiphp_bridge *bridge;
843 struct acpi_device *adev;
844 acpi_handle handle;
845 acpi_status status;
846
847 if (acpiphp_disabled)
848 return;
849
850 adev = ACPI_COMPANION(bus->bridge);
851 if (!adev)
852 return;
853
854 handle = adev->handle;
855 bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
856 if (!bridge)
857 return;
858
859 INIT_LIST_HEAD(&bridge->slots);
860 kref_init(&bridge->ref);
861 bridge->pci_dev = pci_dev_get(bus->self);
862 bridge->pci_bus = bus;
863
864 /*
865 * Grab a ref to the subordinate PCI bus in case the bus is
866 * removed via PCI core logical hotplug. The ref pins the bus
867 * (which we access during module unload).
868 */
869 get_device(&bus->dev);
870
871 acpi_lock_hp_context();
872 if (pci_is_root_bus(bridge->pci_bus)) {
873 struct acpiphp_root_context *root_context;
874
875 root_context = kzalloc(sizeof(*root_context), GFP_KERNEL);
876 if (!root_context)
877 goto err;
878
879 root_context->root_bridge = bridge;
880 acpi_set_hp_context(adev, &root_context->hp);
881 } else {
882 struct acpiphp_context *context;
883
884 /*
885 * This bridge should have been registered as a hotplug function
886 * under its parent, so the context should be there, unless the
887 * parent is going to be handled by pciehp, in which case this
888 * bridge is not interesting to us either.
889 */
890 context = acpiphp_get_context(adev);
891 if (!context)
892 goto err;
893
894 bridge->context = context;
895 context->bridge = bridge;
896 /* Get a reference to the parent bridge. */
897 get_bridge(context->func.parent);
898 }
899 acpi_unlock_hp_context();
900
901 /* Must be added to the list prior to calling acpiphp_add_context(). */
902 mutex_lock(&bridge_mutex);
903 list_add(&bridge->list, &bridge_list);
904 mutex_unlock(&bridge_mutex);
905
906 /* register all slot objects under this bridge */
907 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
908 acpiphp_add_context, NULL, bridge, NULL);
909 if (ACPI_FAILURE(status)) {
910 acpi_handle_err(handle, "failed to register slots\n");
911 cleanup_bridge(bridge);
912 put_bridge(bridge);
913 }
914 return;
915
916 err:
917 acpi_unlock_hp_context();
918 put_device(&bus->dev);
919 pci_dev_put(bridge->pci_dev);
920 kfree(bridge);
921}
922
923static void acpiphp_drop_bridge(struct acpiphp_bridge *bridge)
924{
925 if (pci_is_root_bus(bridge->pci_bus)) {
926 struct acpiphp_root_context *root_context;
927 struct acpi_device *adev;
928
929 acpi_lock_hp_context();
930 adev = ACPI_COMPANION(bridge->pci_bus->bridge);
931 root_context = to_acpiphp_root_context(adev->hp);
932 adev->hp = NULL;
933 acpi_unlock_hp_context();
934 kfree(root_context);
935 }
936 cleanup_bridge(bridge);
937 put_bridge(bridge);
938}
939
940/**
941 * acpiphp_remove_slots - Remove slot objects associated with a given bus.
942 * @bus: PCI bus to remove the slot objects for.
943 */
944void acpiphp_remove_slots(struct pci_bus *bus)
945{
946 struct acpiphp_bridge *bridge;
947
948 if (acpiphp_disabled)
949 return;
950
951 mutex_lock(&bridge_mutex);
952 list_for_each_entry(bridge, &bridge_list, list)
953 if (bridge->pci_bus == bus) {
954 mutex_unlock(&bridge_mutex);
955 acpiphp_drop_bridge(bridge);
956 return;
957 }
958
959 mutex_unlock(&bridge_mutex);
960}
961
962/**
963 * acpiphp_enable_slot - power on slot
964 * @slot: ACPI PHP slot
965 */
966int acpiphp_enable_slot(struct acpiphp_slot *slot)
967{
968 pci_lock_rescan_remove();
969
970 if (slot->flags & SLOT_IS_GOING_AWAY) {
971 pci_unlock_rescan_remove();
972 return -ENODEV;
973 }
974
975 /* configure all functions */
976 if (!(slot->flags & SLOT_ENABLED))
977 enable_slot(slot, false);
978
979 pci_unlock_rescan_remove();
980 return 0;
981}
982
983/**
984 * acpiphp_disable_and_eject_slot - power off and eject slot
985 * @slot: ACPI PHP slot
986 */
987static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
988{
989 struct acpiphp_func *func;
990
991 if (slot->flags & SLOT_IS_GOING_AWAY)
992 return -ENODEV;
993
994 /* unconfigure all functions */
995 disable_slot(slot);
996
997 list_for_each_entry(func, &slot->funcs, sibling)
998 if (func->flags & FUNC_HAS_EJ0) {
999 acpi_handle handle = func_to_handle(func);
1000
1001 if (ACPI_FAILURE(acpi_evaluate_ej0(handle)))
1002 acpi_handle_err(handle, "_EJ0 failed\n");
1003
1004 break;
1005 }
1006
1007 return 0;
1008}
1009
1010int acpiphp_disable_slot(struct acpiphp_slot *slot)
1011{
1012 int ret;
1013
1014 /*
1015 * Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
1016 * acpiphp_disable_and_eject_slot() will be synchronized properly.
1017 */
1018 acpi_scan_lock_acquire();
1019 pci_lock_rescan_remove();
1020 ret = acpiphp_disable_and_eject_slot(slot);
1021 pci_unlock_rescan_remove();
1022 acpi_scan_lock_release();
1023 return ret;
1024}
1025
1026/*
1027 * slot enabled: 1
1028 * slot disabled: 0
1029 */
1030u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
1031{
1032 return (slot->flags & SLOT_ENABLED);
1033}
1034
1035/*
1036 * latch open: 1
1037 * latch closed: 0
1038 */
1039u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
1040{
1041 return !(get_slot_status(slot) & ACPI_STA_DEVICE_UI);
1042}
1043
1044/*
1045 * adapter presence : 1
1046 * absence : 0
1047 */
1048u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
1049{
1050 return !!get_slot_status(slot);
1051}
1/*
2 * ACPI PCI HotPlug glue functions to ACPI CA subsystem
3 *
4 * Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com)
5 * Copyright (C) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com)
6 * Copyright (C) 2002,2003 NEC Corporation
7 * Copyright (C) 2003-2005 Matthew Wilcox (matthew.wilcox@hp.com)
8 * Copyright (C) 2003-2005 Hewlett Packard
9 * Copyright (C) 2005 Rajesh Shah (rajesh.shah@intel.com)
10 * Copyright (C) 2005 Intel Corporation
11 *
12 * All rights reserved.
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or (at
17 * your option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful, but
20 * WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
22 * NON INFRINGEMENT. See the GNU General Public License for more
23 * details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software
27 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28 *
29 * Send feedback to <kristen.c.accardi@intel.com>
30 *
31 */
32
33/*
34 * Lifetime rules for pci_dev:
35 * - The one in acpiphp_bridge has its refcount elevated by pci_get_slot()
36 * when the bridge is scanned and it loses a refcount when the bridge
37 * is removed.
38 * - When a P2P bridge is present, we elevate the refcount on the subordinate
39 * bus. It loses the refcount when the the driver unloads.
40 */
41
42#define pr_fmt(fmt) "acpiphp_glue: " fmt
43
44#include <linux/module.h>
45
46#include <linux/kernel.h>
47#include <linux/pci.h>
48#include <linux/pci_hotplug.h>
49#include <linux/pci-acpi.h>
50#include <linux/pm_runtime.h>
51#include <linux/mutex.h>
52#include <linux/slab.h>
53#include <linux/acpi.h>
54
55#include "../pci.h"
56#include "acpiphp.h"
57
58static LIST_HEAD(bridge_list);
59static DEFINE_MUTEX(bridge_mutex);
60
61static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type);
62static void acpiphp_post_dock_fixup(struct acpi_device *adev);
63static void acpiphp_sanitize_bus(struct pci_bus *bus);
64static void hotplug_event(u32 type, struct acpiphp_context *context);
65static void free_bridge(struct kref *kref);
66
67/**
68 * acpiphp_init_context - Create hotplug context and grab a reference to it.
69 * @adev: ACPI device object to create the context for.
70 *
71 * Call under acpi_hp_context_lock.
72 */
73static struct acpiphp_context *acpiphp_init_context(struct acpi_device *adev)
74{
75 struct acpiphp_context *context;
76
77 context = kzalloc(sizeof(*context), GFP_KERNEL);
78 if (!context)
79 return NULL;
80
81 context->refcount = 1;
82 context->hp.notify = acpiphp_hotplug_notify;
83 context->hp.fixup = acpiphp_post_dock_fixup;
84 acpi_set_hp_context(adev, &context->hp);
85 return context;
86}
87
88/**
89 * acpiphp_get_context - Get hotplug context and grab a reference to it.
90 * @adev: ACPI device object to get the context for.
91 *
92 * Call under acpi_hp_context_lock.
93 */
94static struct acpiphp_context *acpiphp_get_context(struct acpi_device *adev)
95{
96 struct acpiphp_context *context;
97
98 if (!adev->hp)
99 return NULL;
100
101 context = to_acpiphp_context(adev->hp);
102 context->refcount++;
103 return context;
104}
105
106/**
107 * acpiphp_put_context - Drop a reference to ACPI hotplug context.
108 * @context: ACPI hotplug context to drop a reference to.
109 *
110 * The context object is removed if there are no more references to it.
111 *
112 * Call under acpi_hp_context_lock.
113 */
114static void acpiphp_put_context(struct acpiphp_context *context)
115{
116 if (--context->refcount)
117 return;
118
119 WARN_ON(context->bridge);
120 context->hp.self->hp = NULL;
121 kfree(context);
122}
123
124static inline void get_bridge(struct acpiphp_bridge *bridge)
125{
126 kref_get(&bridge->ref);
127}
128
129static inline void put_bridge(struct acpiphp_bridge *bridge)
130{
131 kref_put(&bridge->ref, free_bridge);
132}
133
134static struct acpiphp_context *acpiphp_grab_context(struct acpi_device *adev)
135{
136 struct acpiphp_context *context;
137
138 acpi_lock_hp_context();
139 context = acpiphp_get_context(adev);
140 if (!context || context->func.parent->is_going_away) {
141 acpi_unlock_hp_context();
142 return NULL;
143 }
144 get_bridge(context->func.parent);
145 acpiphp_put_context(context);
146 acpi_unlock_hp_context();
147 return context;
148}
149
150static void acpiphp_let_context_go(struct acpiphp_context *context)
151{
152 put_bridge(context->func.parent);
153}
154
155static void free_bridge(struct kref *kref)
156{
157 struct acpiphp_context *context;
158 struct acpiphp_bridge *bridge;
159 struct acpiphp_slot *slot, *next;
160 struct acpiphp_func *func, *tmp;
161
162 acpi_lock_hp_context();
163
164 bridge = container_of(kref, struct acpiphp_bridge, ref);
165
166 list_for_each_entry_safe(slot, next, &bridge->slots, node) {
167 list_for_each_entry_safe(func, tmp, &slot->funcs, sibling)
168 acpiphp_put_context(func_to_context(func));
169
170 kfree(slot);
171 }
172
173 context = bridge->context;
174 /* Root bridges will not have hotplug context. */
175 if (context) {
176 /* Release the reference taken by acpiphp_enumerate_slots(). */
177 put_bridge(context->func.parent);
178 context->bridge = NULL;
179 acpiphp_put_context(context);
180 }
181
182 put_device(&bridge->pci_bus->dev);
183 pci_dev_put(bridge->pci_dev);
184 kfree(bridge);
185
186 acpi_unlock_hp_context();
187}
188
189/**
190 * acpiphp_post_dock_fixup - Post-dock fixups for PCI devices.
191 * @adev: ACPI device object corresponding to a PCI device.
192 *
193 * TBD - figure out a way to only call fixups for systems that require them.
194 */
195static void acpiphp_post_dock_fixup(struct acpi_device *adev)
196{
197 struct acpiphp_context *context = acpiphp_grab_context(adev);
198 struct pci_bus *bus;
199 u32 buses;
200
201 if (!context)
202 return;
203
204 bus = context->func.slot->bus;
205 if (!bus->self)
206 goto out;
207
208 /* fixup bad _DCK function that rewrites
209 * secondary bridge on slot
210 */
211 pci_read_config_dword(bus->self, PCI_PRIMARY_BUS, &buses);
212
213 if (((buses >> 8) & 0xff) != bus->busn_res.start) {
214 buses = (buses & 0xff000000)
215 | ((unsigned int)(bus->primary) << 0)
216 | ((unsigned int)(bus->busn_res.start) << 8)
217 | ((unsigned int)(bus->busn_res.end) << 16);
218 pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
219 }
220
221 out:
222 acpiphp_let_context_go(context);
223}
224
225/* Check whether the PCI device is managed by native PCIe hotplug driver */
226static bool device_is_managed_by_native_pciehp(struct pci_dev *pdev)
227{
228 u32 reg32;
229 acpi_handle tmp;
230 struct acpi_pci_root *root;
231
232 /* Check whether the PCIe port supports native PCIe hotplug */
233 if (pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32))
234 return false;
235 if (!(reg32 & PCI_EXP_SLTCAP_HPC))
236 return false;
237
238 /*
239 * Check whether native PCIe hotplug has been enabled for
240 * this PCIe hierarchy.
241 */
242 tmp = acpi_find_root_bridge_handle(pdev);
243 if (!tmp)
244 return false;
245 root = acpi_pci_find_root(tmp);
246 if (!root)
247 return false;
248 if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
249 return false;
250
251 return true;
252}
253
254/**
255 * acpiphp_add_context - Add ACPIPHP context to an ACPI device object.
256 * @handle: ACPI handle of the object to add a context to.
257 * @lvl: Not used.
258 * @data: The object's parent ACPIPHP bridge.
259 * @rv: Not used.
260 */
261static acpi_status acpiphp_add_context(acpi_handle handle, u32 lvl, void *data,
262 void **rv)
263{
264 struct acpiphp_bridge *bridge = data;
265 struct acpiphp_context *context;
266 struct acpi_device *adev;
267 struct acpiphp_slot *slot;
268 struct acpiphp_func *newfunc;
269 acpi_status status = AE_OK;
270 unsigned long long adr;
271 int device, function;
272 struct pci_bus *pbus = bridge->pci_bus;
273 struct pci_dev *pdev = bridge->pci_dev;
274 u32 val;
275
276 status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
277 if (ACPI_FAILURE(status)) {
278 if (status != AE_NOT_FOUND)
279 acpi_handle_warn(handle,
280 "can't evaluate _ADR (%#x)\n", status);
281 return AE_OK;
282 }
283 if (acpi_bus_get_device(handle, &adev))
284 return AE_OK;
285
286 device = (adr >> 16) & 0xffff;
287 function = adr & 0xffff;
288
289 acpi_lock_hp_context();
290 context = acpiphp_init_context(adev);
291 if (!context) {
292 acpi_unlock_hp_context();
293 acpi_handle_err(handle, "No hotplug context\n");
294 return AE_NOT_EXIST;
295 }
296 newfunc = &context->func;
297 newfunc->function = function;
298 newfunc->parent = bridge;
299 acpi_unlock_hp_context();
300
301 /*
302 * If this is a dock device, its _EJ0 should be executed by the dock
303 * notify handler after calling _DCK.
304 */
305 if (!is_dock_device(adev) && acpi_has_method(handle, "_EJ0"))
306 newfunc->flags = FUNC_HAS_EJ0;
307
308 if (acpi_has_method(handle, "_STA"))
309 newfunc->flags |= FUNC_HAS_STA;
310
311 /* search for objects that share the same slot */
312 list_for_each_entry(slot, &bridge->slots, node)
313 if (slot->device == device)
314 goto slot_found;
315
316 slot = kzalloc(sizeof(struct acpiphp_slot), GFP_KERNEL);
317 if (!slot) {
318 acpi_lock_hp_context();
319 acpiphp_put_context(context);
320 acpi_unlock_hp_context();
321 return AE_NO_MEMORY;
322 }
323
324 slot->bus = bridge->pci_bus;
325 slot->device = device;
326 INIT_LIST_HEAD(&slot->funcs);
327
328 list_add_tail(&slot->node, &bridge->slots);
329
330 /*
331 * Expose slots to user space for functions that have _EJ0 or _RMV or
332 * are located in dock stations. Do not expose them for devices handled
333 * by the native PCIe hotplug (PCIeHP), becuase that code is supposed to
334 * expose slots to user space in those cases.
335 */
336 if ((acpi_pci_check_ejectable(pbus, handle) || is_dock_device(adev))
337 && !(pdev && device_is_managed_by_native_pciehp(pdev))) {
338 unsigned long long sun;
339 int retval;
340
341 bridge->nr_slots++;
342 status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
343 if (ACPI_FAILURE(status))
344 sun = bridge->nr_slots;
345
346 pr_debug("found ACPI PCI Hotplug slot %llu at PCI %04x:%02x:%02x\n",
347 sun, pci_domain_nr(pbus), pbus->number, device);
348
349 retval = acpiphp_register_hotplug_slot(slot, sun);
350 if (retval) {
351 slot->slot = NULL;
352 bridge->nr_slots--;
353 if (retval == -EBUSY)
354 pr_warn("Slot %llu already registered by another hotplug driver\n", sun);
355 else
356 pr_warn("acpiphp_register_hotplug_slot failed (err code = 0x%x)\n", retval);
357 }
358 /* Even if the slot registration fails, we can still use it. */
359 }
360
361 slot_found:
362 newfunc->slot = slot;
363 list_add_tail(&newfunc->sibling, &slot->funcs);
364
365 if (pci_bus_read_dev_vendor_id(pbus, PCI_DEVFN(device, function),
366 &val, 60*1000))
367 slot->flags |= SLOT_ENABLED;
368
369 return AE_OK;
370}
371
372static void cleanup_bridge(struct acpiphp_bridge *bridge)
373{
374 struct acpiphp_slot *slot;
375 struct acpiphp_func *func;
376
377 list_for_each_entry(slot, &bridge->slots, node) {
378 list_for_each_entry(func, &slot->funcs, sibling) {
379 struct acpi_device *adev = func_to_acpi_device(func);
380
381 acpi_lock_hp_context();
382 adev->hp->notify = NULL;
383 adev->hp->fixup = NULL;
384 acpi_unlock_hp_context();
385 }
386 slot->flags |= SLOT_IS_GOING_AWAY;
387 if (slot->slot)
388 acpiphp_unregister_hotplug_slot(slot);
389 }
390
391 mutex_lock(&bridge_mutex);
392 list_del(&bridge->list);
393 mutex_unlock(&bridge_mutex);
394
395 acpi_lock_hp_context();
396 bridge->is_going_away = true;
397 acpi_unlock_hp_context();
398}
399
400/**
401 * acpiphp_max_busnr - return the highest reserved bus number under the given bus.
402 * @bus: bus to start search with
403 */
404static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
405{
406 struct pci_bus *tmp;
407 unsigned char max, n;
408
409 /*
410 * pci_bus_max_busnr will return the highest
411 * reserved busnr for all these children.
412 * that is equivalent to the bus->subordinate
413 * value. We don't want to use the parent's
414 * bus->subordinate value because it could have
415 * padding in it.
416 */
417 max = bus->busn_res.start;
418
419 list_for_each_entry(tmp, &bus->children, node) {
420 n = pci_bus_max_busnr(tmp);
421 if (n > max)
422 max = n;
423 }
424 return max;
425}
426
427static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
428{
429 struct acpiphp_func *func;
430 union acpi_object params[2];
431 struct acpi_object_list arg_list;
432
433 list_for_each_entry(func, &slot->funcs, sibling) {
434 arg_list.count = 2;
435 arg_list.pointer = params;
436 params[0].type = ACPI_TYPE_INTEGER;
437 params[0].integer.value = ACPI_ADR_SPACE_PCI_CONFIG;
438 params[1].type = ACPI_TYPE_INTEGER;
439 params[1].integer.value = 1;
440 /* _REG is optional, we don't care about if there is failure */
441 acpi_evaluate_object(func_to_handle(func), "_REG", &arg_list,
442 NULL);
443 }
444}
445
446static void check_hotplug_bridge(struct acpiphp_slot *slot, struct pci_dev *dev)
447{
448 struct acpiphp_func *func;
449
450 /* quirk, or pcie could set it already */
451 if (dev->is_hotplug_bridge)
452 return;
453
454 list_for_each_entry(func, &slot->funcs, sibling) {
455 if (PCI_FUNC(dev->devfn) == func->function) {
456 dev->is_hotplug_bridge = 1;
457 break;
458 }
459 }
460}
461
462static int acpiphp_rescan_slot(struct acpiphp_slot *slot)
463{
464 struct acpiphp_func *func;
465
466 list_for_each_entry(func, &slot->funcs, sibling) {
467 struct acpi_device *adev = func_to_acpi_device(func);
468
469 acpi_bus_scan(adev->handle);
470 if (acpi_device_enumerated(adev))
471 acpi_device_set_power(adev, ACPI_STATE_D0);
472 }
473 return pci_scan_slot(slot->bus, PCI_DEVFN(slot->device, 0));
474}
475
476/**
477 * enable_slot - enable, configure a slot
478 * @slot: slot to be enabled
479 *
480 * This function should be called per *physical slot*,
481 * not per each slot object in ACPI namespace.
482 */
483static void enable_slot(struct acpiphp_slot *slot)
484{
485 struct pci_dev *dev;
486 struct pci_bus *bus = slot->bus;
487 struct acpiphp_func *func;
488 int max, pass;
489 LIST_HEAD(add_list);
490
491 acpiphp_rescan_slot(slot);
492 max = acpiphp_max_busnr(bus);
493 for (pass = 0; pass < 2; pass++) {
494 list_for_each_entry(dev, &bus->devices, bus_list) {
495 if (PCI_SLOT(dev->devfn) != slot->device)
496 continue;
497
498 if (pci_is_bridge(dev)) {
499 max = pci_scan_bridge(bus, dev, max, pass);
500 if (pass && dev->subordinate) {
501 check_hotplug_bridge(slot, dev);
502 pcibios_resource_survey_bus(dev->subordinate);
503 __pci_bus_size_bridges(dev->subordinate,
504 &add_list);
505 }
506 }
507 }
508 }
509 __pci_bus_assign_resources(bus, &add_list, NULL);
510
511 acpiphp_sanitize_bus(bus);
512 pcie_bus_configure_settings(bus);
513 acpiphp_set_acpi_region(slot);
514
515 list_for_each_entry(dev, &bus->devices, bus_list) {
516 /* Assume that newly added devices are powered on already. */
517 if (!dev->is_added)
518 dev->current_state = PCI_D0;
519 }
520
521 pci_bus_add_devices(bus);
522
523 slot->flags |= SLOT_ENABLED;
524 list_for_each_entry(func, &slot->funcs, sibling) {
525 dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
526 func->function));
527 if (!dev) {
528 /* Do not set SLOT_ENABLED flag if some funcs
529 are not added. */
530 slot->flags &= (~SLOT_ENABLED);
531 continue;
532 }
533 }
534}
535
536/**
537 * disable_slot - disable a slot
538 * @slot: ACPI PHP slot
539 */
540static void disable_slot(struct acpiphp_slot *slot)
541{
542 struct pci_bus *bus = slot->bus;
543 struct pci_dev *dev, *prev;
544 struct acpiphp_func *func;
545
546 /*
547 * enable_slot() enumerates all functions in this device via
548 * pci_scan_slot(), whether they have associated ACPI hotplug
549 * methods (_EJ0, etc.) or not. Therefore, we remove all functions
550 * here.
551 */
552 list_for_each_entry_safe_reverse(dev, prev, &bus->devices, bus_list)
553 if (PCI_SLOT(dev->devfn) == slot->device)
554 pci_stop_and_remove_bus_device(dev);
555
556 list_for_each_entry(func, &slot->funcs, sibling)
557 acpi_bus_trim(func_to_acpi_device(func));
558
559 slot->flags &= (~SLOT_ENABLED);
560}
561
562static bool slot_no_hotplug(struct acpiphp_slot *slot)
563{
564 struct pci_bus *bus = slot->bus;
565 struct pci_dev *dev;
566
567 list_for_each_entry(dev, &bus->devices, bus_list) {
568 if (PCI_SLOT(dev->devfn) == slot->device && dev->ignore_hotplug)
569 return true;
570 }
571 return false;
572}
573
574/**
575 * get_slot_status - get ACPI slot status
576 * @slot: ACPI PHP slot
577 *
578 * If a slot has _STA for each function and if any one of them
579 * returned non-zero status, return it.
580 *
581 * If a slot doesn't have _STA and if any one of its functions'
582 * configuration space is configured, return 0x0f as a _STA.
583 *
584 * Otherwise return 0.
585 */
586static unsigned int get_slot_status(struct acpiphp_slot *slot)
587{
588 unsigned long long sta = 0;
589 struct acpiphp_func *func;
590
591 list_for_each_entry(func, &slot->funcs, sibling) {
592 if (func->flags & FUNC_HAS_STA) {
593 acpi_status status;
594
595 status = acpi_evaluate_integer(func_to_handle(func),
596 "_STA", NULL, &sta);
597 if (ACPI_SUCCESS(status) && sta)
598 break;
599 } else {
600 u32 dvid;
601
602 pci_bus_read_config_dword(slot->bus,
603 PCI_DEVFN(slot->device,
604 func->function),
605 PCI_VENDOR_ID, &dvid);
606 if (dvid != 0xffffffff) {
607 sta = ACPI_STA_ALL;
608 break;
609 }
610 }
611 }
612
613 return (unsigned int)sta;
614}
615
616static inline bool device_status_valid(unsigned int sta)
617{
618 /*
619 * ACPI spec says that _STA may return bit 0 clear with bit 3 set
620 * if the device is valid but does not require a device driver to be
621 * loaded (Section 6.3.7 of ACPI 5.0A).
622 */
623 unsigned int mask = ACPI_STA_DEVICE_ENABLED | ACPI_STA_DEVICE_FUNCTIONING;
624 return (sta & mask) == mask;
625}
626
627/**
628 * trim_stale_devices - remove PCI devices that are not responding.
629 * @dev: PCI device to start walking the hierarchy from.
630 */
631static void trim_stale_devices(struct pci_dev *dev)
632{
633 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
634 struct pci_bus *bus = dev->subordinate;
635 bool alive = dev->ignore_hotplug;
636
637 if (adev) {
638 acpi_status status;
639 unsigned long long sta;
640
641 status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
642 alive = alive || (ACPI_SUCCESS(status) && device_status_valid(sta));
643 }
644 if (!alive)
645 alive = pci_device_is_present(dev);
646
647 if (!alive) {
648 pci_stop_and_remove_bus_device(dev);
649 if (adev)
650 acpi_bus_trim(adev);
651 } else if (bus) {
652 struct pci_dev *child, *tmp;
653
654 /* The device is a bridge. so check the bus below it. */
655 pm_runtime_get_sync(&dev->dev);
656 list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
657 trim_stale_devices(child);
658
659 pm_runtime_put(&dev->dev);
660 }
661}
662
663/**
664 * acpiphp_check_bridge - re-enumerate devices
665 * @bridge: where to begin re-enumeration
666 *
667 * Iterate over all slots under this bridge and make sure that if a
668 * card is present they are enabled, and if not they are disabled.
669 */
670static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
671{
672 struct acpiphp_slot *slot;
673
674 /* Bail out if the bridge is going away. */
675 if (bridge->is_going_away)
676 return;
677
678 list_for_each_entry(slot, &bridge->slots, node) {
679 struct pci_bus *bus = slot->bus;
680 struct pci_dev *dev, *tmp;
681
682 if (slot_no_hotplug(slot)) {
683 ; /* do nothing */
684 } else if (device_status_valid(get_slot_status(slot))) {
685 /* remove stale devices if any */
686 list_for_each_entry_safe_reverse(dev, tmp,
687 &bus->devices, bus_list)
688 if (PCI_SLOT(dev->devfn) == slot->device)
689 trim_stale_devices(dev);
690
691 /* configure all functions */
692 enable_slot(slot);
693 } else {
694 disable_slot(slot);
695 }
696 }
697}
698
699/*
700 * Remove devices for which we could not assign resources, call
701 * arch specific code to fix-up the bus
702 */
703static void acpiphp_sanitize_bus(struct pci_bus *bus)
704{
705 struct pci_dev *dev, *tmp;
706 int i;
707 unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
708
709 list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
710 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
711 struct resource *res = &dev->resource[i];
712 if ((res->flags & type_mask) && !res->start &&
713 res->end) {
714 /* Could not assign a required resources
715 * for this device, remove it */
716 pci_stop_and_remove_bus_device(dev);
717 break;
718 }
719 }
720 }
721}
722
723/*
724 * ACPI event handlers
725 */
726
727void acpiphp_check_host_bridge(struct acpi_device *adev)
728{
729 struct acpiphp_bridge *bridge = NULL;
730
731 acpi_lock_hp_context();
732 if (adev->hp) {
733 bridge = to_acpiphp_root_context(adev->hp)->root_bridge;
734 if (bridge)
735 get_bridge(bridge);
736 }
737 acpi_unlock_hp_context();
738 if (bridge) {
739 pci_lock_rescan_remove();
740
741 acpiphp_check_bridge(bridge);
742
743 pci_unlock_rescan_remove();
744 put_bridge(bridge);
745 }
746}
747
748static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
749
750static void hotplug_event(u32 type, struct acpiphp_context *context)
751{
752 acpi_handle handle = context->hp.self->handle;
753 struct acpiphp_func *func = &context->func;
754 struct acpiphp_slot *slot = func->slot;
755 struct acpiphp_bridge *bridge;
756
757 acpi_lock_hp_context();
758 bridge = context->bridge;
759 if (bridge)
760 get_bridge(bridge);
761
762 acpi_unlock_hp_context();
763
764 pci_lock_rescan_remove();
765
766 switch (type) {
767 case ACPI_NOTIFY_BUS_CHECK:
768 /* bus re-enumerate */
769 acpi_handle_debug(handle, "Bus check in %s()\n", __func__);
770 if (bridge)
771 acpiphp_check_bridge(bridge);
772 else if (!(slot->flags & SLOT_IS_GOING_AWAY))
773 enable_slot(slot);
774
775 break;
776
777 case ACPI_NOTIFY_DEVICE_CHECK:
778 /* device check */
779 acpi_handle_debug(handle, "Device check in %s()\n", __func__);
780 if (bridge) {
781 acpiphp_check_bridge(bridge);
782 } else if (!(slot->flags & SLOT_IS_GOING_AWAY)) {
783 /*
784 * Check if anything has changed in the slot and rescan
785 * from the parent if that's the case.
786 */
787 if (acpiphp_rescan_slot(slot))
788 acpiphp_check_bridge(func->parent);
789 }
790 break;
791
792 case ACPI_NOTIFY_EJECT_REQUEST:
793 /* request device eject */
794 acpi_handle_debug(handle, "Eject request in %s()\n", __func__);
795 acpiphp_disable_and_eject_slot(slot);
796 break;
797 }
798
799 pci_unlock_rescan_remove();
800 if (bridge)
801 put_bridge(bridge);
802}
803
804static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type)
805{
806 struct acpiphp_context *context;
807
808 context = acpiphp_grab_context(adev);
809 if (!context)
810 return -ENODATA;
811
812 hotplug_event(type, context);
813 acpiphp_let_context_go(context);
814 return 0;
815}
816
817/**
818 * acpiphp_enumerate_slots - Enumerate PCI slots for a given bus.
819 * @bus: PCI bus to enumerate the slots for.
820 *
821 * A "slot" is an object associated with a PCI device number. All functions
822 * (PCI devices) with the same bus and device number belong to the same slot.
823 */
824void acpiphp_enumerate_slots(struct pci_bus *bus)
825{
826 struct acpiphp_bridge *bridge;
827 struct acpi_device *adev;
828 acpi_handle handle;
829 acpi_status status;
830
831 if (acpiphp_disabled)
832 return;
833
834 adev = ACPI_COMPANION(bus->bridge);
835 if (!adev)
836 return;
837
838 handle = adev->handle;
839 bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
840 if (!bridge) {
841 acpi_handle_err(handle, "No memory for bridge object\n");
842 return;
843 }
844
845 INIT_LIST_HEAD(&bridge->slots);
846 kref_init(&bridge->ref);
847 bridge->pci_dev = pci_dev_get(bus->self);
848 bridge->pci_bus = bus;
849
850 /*
851 * Grab a ref to the subordinate PCI bus in case the bus is
852 * removed via PCI core logical hotplug. The ref pins the bus
853 * (which we access during module unload).
854 */
855 get_device(&bus->dev);
856
857 acpi_lock_hp_context();
858 if (pci_is_root_bus(bridge->pci_bus)) {
859 struct acpiphp_root_context *root_context;
860
861 root_context = kzalloc(sizeof(*root_context), GFP_KERNEL);
862 if (!root_context)
863 goto err;
864
865 root_context->root_bridge = bridge;
866 acpi_set_hp_context(adev, &root_context->hp);
867 } else {
868 struct acpiphp_context *context;
869
870 /*
871 * This bridge should have been registered as a hotplug function
872 * under its parent, so the context should be there, unless the
873 * parent is going to be handled by pciehp, in which case this
874 * bridge is not interesting to us either.
875 */
876 context = acpiphp_get_context(adev);
877 if (!context)
878 goto err;
879
880 bridge->context = context;
881 context->bridge = bridge;
882 /* Get a reference to the parent bridge. */
883 get_bridge(context->func.parent);
884 }
885 acpi_unlock_hp_context();
886
887 /* Must be added to the list prior to calling acpiphp_add_context(). */
888 mutex_lock(&bridge_mutex);
889 list_add(&bridge->list, &bridge_list);
890 mutex_unlock(&bridge_mutex);
891
892 /* register all slot objects under this bridge */
893 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
894 acpiphp_add_context, NULL, bridge, NULL);
895 if (ACPI_FAILURE(status)) {
896 acpi_handle_err(handle, "failed to register slots\n");
897 cleanup_bridge(bridge);
898 put_bridge(bridge);
899 }
900 return;
901
902 err:
903 acpi_unlock_hp_context();
904 put_device(&bus->dev);
905 pci_dev_put(bridge->pci_dev);
906 kfree(bridge);
907}
908
909static void acpiphp_drop_bridge(struct acpiphp_bridge *bridge)
910{
911 if (pci_is_root_bus(bridge->pci_bus)) {
912 struct acpiphp_root_context *root_context;
913 struct acpi_device *adev;
914
915 acpi_lock_hp_context();
916 adev = ACPI_COMPANION(bridge->pci_bus->bridge);
917 root_context = to_acpiphp_root_context(adev->hp);
918 adev->hp = NULL;
919 acpi_unlock_hp_context();
920 kfree(root_context);
921 }
922 cleanup_bridge(bridge);
923 put_bridge(bridge);
924}
925
926/**
927 * acpiphp_remove_slots - Remove slot objects associated with a given bus.
928 * @bus: PCI bus to remove the slot objects for.
929 */
930void acpiphp_remove_slots(struct pci_bus *bus)
931{
932 struct acpiphp_bridge *bridge;
933
934 if (acpiphp_disabled)
935 return;
936
937 mutex_lock(&bridge_mutex);
938 list_for_each_entry(bridge, &bridge_list, list)
939 if (bridge->pci_bus == bus) {
940 mutex_unlock(&bridge_mutex);
941 acpiphp_drop_bridge(bridge);
942 return;
943 }
944
945 mutex_unlock(&bridge_mutex);
946}
947
948/**
949 * acpiphp_enable_slot - power on slot
950 * @slot: ACPI PHP slot
951 */
952int acpiphp_enable_slot(struct acpiphp_slot *slot)
953{
954 pci_lock_rescan_remove();
955
956 if (slot->flags & SLOT_IS_GOING_AWAY) {
957 pci_unlock_rescan_remove();
958 return -ENODEV;
959 }
960
961 /* configure all functions */
962 if (!(slot->flags & SLOT_ENABLED))
963 enable_slot(slot);
964
965 pci_unlock_rescan_remove();
966 return 0;
967}
968
969/**
970 * acpiphp_disable_and_eject_slot - power off and eject slot
971 * @slot: ACPI PHP slot
972 */
973static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
974{
975 struct acpiphp_func *func;
976
977 if (slot->flags & SLOT_IS_GOING_AWAY)
978 return -ENODEV;
979
980 /* unconfigure all functions */
981 disable_slot(slot);
982
983 list_for_each_entry(func, &slot->funcs, sibling)
984 if (func->flags & FUNC_HAS_EJ0) {
985 acpi_handle handle = func_to_handle(func);
986
987 if (ACPI_FAILURE(acpi_evaluate_ej0(handle)))
988 acpi_handle_err(handle, "_EJ0 failed\n");
989
990 break;
991 }
992
993 return 0;
994}
995
996int acpiphp_disable_slot(struct acpiphp_slot *slot)
997{
998 int ret;
999
1000 /*
1001 * Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
1002 * acpiphp_disable_and_eject_slot() will be synchronized properly.
1003 */
1004 acpi_scan_lock_acquire();
1005 pci_lock_rescan_remove();
1006 ret = acpiphp_disable_and_eject_slot(slot);
1007 pci_unlock_rescan_remove();
1008 acpi_scan_lock_release();
1009 return ret;
1010}
1011
1012/*
1013 * slot enabled: 1
1014 * slot disabled: 0
1015 */
1016u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
1017{
1018 return (slot->flags & SLOT_ENABLED);
1019}
1020
1021/*
1022 * latch open: 1
1023 * latch closed: 0
1024 */
1025u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
1026{
1027 return !(get_slot_status(slot) & ACPI_STA_DEVICE_UI);
1028}
1029
1030/*
1031 * adapter presence : 1
1032 * absence : 0
1033 */
1034u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
1035{
1036 return !!get_slot_status(slot);
1037}