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
44 static LIST_HEAD(bridge_list);
45 static DEFINE_MUTEX(bridge_mutex);
46
47 static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type);
48 static void acpiphp_post_dock_fixup(struct acpi_device *adev);
49 static void acpiphp_sanitize_bus(struct pci_bus *bus);
50 static void hotplug_event(u32 type, struct acpiphp_context *context);
51 static 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 */
acpiphp_init_context(struct acpi_device * adev)59 static 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 */
acpiphp_get_context(struct acpi_device * adev)80 static 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 */
acpiphp_put_context(struct acpiphp_context * context)100 static 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
get_bridge(struct acpiphp_bridge * bridge)110 static inline void get_bridge(struct acpiphp_bridge *bridge)
111 {
112 kref_get(&bridge->ref);
113 }
114
put_bridge(struct acpiphp_bridge * bridge)115 static inline void put_bridge(struct acpiphp_bridge *bridge)
116 {
117 kref_put(&bridge->ref, free_bridge);
118 }
119
acpiphp_grab_context(struct acpi_device * adev)120 static struct acpiphp_context *acpiphp_grab_context(struct acpi_device *adev)
121 {
122 struct acpiphp_context *context;
123
124 acpi_lock_hp_context();
125
126 context = acpiphp_get_context(adev);
127 if (!context)
128 goto unlock;
129
130 if (context->func.parent->is_going_away) {
131 acpiphp_put_context(context);
132 context = NULL;
133 goto unlock;
134 }
135
136 get_bridge(context->func.parent);
137 acpiphp_put_context(context);
138
139 unlock:
140 acpi_unlock_hp_context();
141 return context;
142 }
143
acpiphp_let_context_go(struct acpiphp_context * context)144 static void acpiphp_let_context_go(struct acpiphp_context *context)
145 {
146 put_bridge(context->func.parent);
147 }
148
free_bridge(struct kref * kref)149 static void free_bridge(struct kref *kref)
150 {
151 struct acpiphp_context *context;
152 struct acpiphp_bridge *bridge;
153 struct acpiphp_slot *slot, *next;
154 struct acpiphp_func *func, *tmp;
155
156 acpi_lock_hp_context();
157
158 bridge = container_of(kref, struct acpiphp_bridge, ref);
159
160 list_for_each_entry_safe(slot, next, &bridge->slots, node) {
161 list_for_each_entry_safe(func, tmp, &slot->funcs, sibling)
162 acpiphp_put_context(func_to_context(func));
163
164 kfree(slot);
165 }
166
167 context = bridge->context;
168 /* Root bridges will not have hotplug context. */
169 if (context) {
170 /* Release the reference taken by acpiphp_enumerate_slots(). */
171 put_bridge(context->func.parent);
172 context->bridge = NULL;
173 acpiphp_put_context(context);
174 }
175
176 put_device(&bridge->pci_bus->dev);
177 pci_dev_put(bridge->pci_dev);
178 kfree(bridge);
179
180 acpi_unlock_hp_context();
181 }
182
183 /**
184 * acpiphp_post_dock_fixup - Post-dock fixups for PCI devices.
185 * @adev: ACPI device object corresponding to a PCI device.
186 *
187 * TBD - figure out a way to only call fixups for systems that require them.
188 */
acpiphp_post_dock_fixup(struct acpi_device * adev)189 static void acpiphp_post_dock_fixup(struct acpi_device *adev)
190 {
191 struct acpiphp_context *context = acpiphp_grab_context(adev);
192 struct pci_bus *bus;
193 u32 buses;
194
195 if (!context)
196 return;
197
198 bus = context->func.slot->bus;
199 if (!bus->self)
200 goto out;
201
202 /* fixup bad _DCK function that rewrites
203 * secondary bridge on slot
204 */
205 pci_read_config_dword(bus->self, PCI_PRIMARY_BUS, &buses);
206
207 if (((buses >> 8) & 0xff) != bus->busn_res.start) {
208 buses = (buses & 0xff000000)
209 | ((unsigned int)(bus->primary) << 0)
210 | ((unsigned int)(bus->busn_res.start) << 8)
211 | ((unsigned int)(bus->busn_res.end) << 16);
212 pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
213 }
214
215 out:
216 acpiphp_let_context_go(context);
217 }
218
219 /**
220 * acpiphp_add_context - Add ACPIPHP context to an ACPI device object.
221 * @handle: ACPI handle of the object to add a context to.
222 * @lvl: Not used.
223 * @data: The object's parent ACPIPHP bridge.
224 * @rv: Not used.
225 */
acpiphp_add_context(acpi_handle handle,u32 lvl,void * data,void ** rv)226 static acpi_status acpiphp_add_context(acpi_handle handle, u32 lvl, void *data,
227 void **rv)
228 {
229 struct acpiphp_bridge *bridge = data;
230 struct acpiphp_context *context;
231 struct acpi_device *adev;
232 struct acpiphp_slot *slot;
233 struct acpiphp_func *newfunc;
234 acpi_status status = AE_OK;
235 unsigned long long adr;
236 int device, function;
237 struct pci_bus *pbus = bridge->pci_bus;
238 struct pci_dev *pdev = bridge->pci_dev;
239 u32 val;
240
241 status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
242 if (ACPI_FAILURE(status)) {
243 if (status != AE_NOT_FOUND)
244 acpi_handle_warn(handle,
245 "can't evaluate _ADR (%#x)\n", status);
246 return AE_OK;
247 }
248 if (acpi_bus_get_device(handle, &adev))
249 return AE_OK;
250
251 device = (adr >> 16) & 0xffff;
252 function = adr & 0xffff;
253
254 acpi_lock_hp_context();
255 context = acpiphp_init_context(adev);
256 if (!context) {
257 acpi_unlock_hp_context();
258 acpi_handle_err(handle, "No hotplug context\n");
259 return AE_NOT_EXIST;
260 }
261 newfunc = &context->func;
262 newfunc->function = function;
263 newfunc->parent = bridge;
264 acpi_unlock_hp_context();
265
266 /*
267 * If this is a dock device, its _EJ0 should be executed by the dock
268 * notify handler after calling _DCK.
269 */
270 if (!is_dock_device(adev) && acpi_has_method(handle, "_EJ0"))
271 newfunc->flags = FUNC_HAS_EJ0;
272
273 if (acpi_has_method(handle, "_STA"))
274 newfunc->flags |= FUNC_HAS_STA;
275
276 /* search for objects that share the same slot */
277 list_for_each_entry(slot, &bridge->slots, node)
278 if (slot->device == device)
279 goto slot_found;
280
281 slot = kzalloc(sizeof(struct acpiphp_slot), GFP_KERNEL);
282 if (!slot) {
283 acpi_lock_hp_context();
284 acpiphp_put_context(context);
285 acpi_unlock_hp_context();
286 return AE_NO_MEMORY;
287 }
288
289 slot->bus = bridge->pci_bus;
290 slot->device = device;
291 INIT_LIST_HEAD(&slot->funcs);
292
293 list_add_tail(&slot->node, &bridge->slots);
294
295 /*
296 * Expose slots to user space for functions that have _EJ0 or _RMV or
297 * are located in dock stations. Do not expose them for devices handled
298 * by the native PCIe hotplug (PCIeHP) or standard PCI hotplug
299 * (SHPCHP), because that code is supposed to expose slots to user
300 * space in those cases.
301 */
302 if ((acpi_pci_check_ejectable(pbus, handle) || is_dock_device(adev))
303 && !(pdev && hotplug_is_native(pdev))) {
304 unsigned long long sun;
305 int retval;
306
307 bridge->nr_slots++;
308 status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
309 if (ACPI_FAILURE(status))
310 sun = bridge->nr_slots;
311
312 pr_debug("found ACPI PCI Hotplug slot %llu at PCI %04x:%02x:%02x\n",
313 sun, pci_domain_nr(pbus), pbus->number, device);
314
315 retval = acpiphp_register_hotplug_slot(slot, sun);
316 if (retval) {
317 slot->slot = NULL;
318 bridge->nr_slots--;
319 if (retval == -EBUSY)
320 pr_warn("Slot %llu already registered by another hotplug driver\n", sun);
321 else
322 pr_warn("acpiphp_register_hotplug_slot failed (err code = 0x%x)\n", retval);
323 }
324 /* Even if the slot registration fails, we can still use it. */
325 }
326
327 slot_found:
328 newfunc->slot = slot;
329 list_add_tail(&newfunc->sibling, &slot->funcs);
330
331 if (pci_bus_read_dev_vendor_id(pbus, PCI_DEVFN(device, function),
332 &val, 60*1000))
333 slot->flags |= SLOT_ENABLED;
334
335 return AE_OK;
336 }
337
cleanup_bridge(struct acpiphp_bridge * bridge)338 static void cleanup_bridge(struct acpiphp_bridge *bridge)
339 {
340 struct acpiphp_slot *slot;
341 struct acpiphp_func *func;
342
343 list_for_each_entry(slot, &bridge->slots, node) {
344 list_for_each_entry(func, &slot->funcs, sibling) {
345 struct acpi_device *adev = func_to_acpi_device(func);
346
347 acpi_lock_hp_context();
348 adev->hp->notify = NULL;
349 adev->hp->fixup = NULL;
350 acpi_unlock_hp_context();
351 }
352 slot->flags |= SLOT_IS_GOING_AWAY;
353 if (slot->slot)
354 acpiphp_unregister_hotplug_slot(slot);
355 }
356
357 mutex_lock(&bridge_mutex);
358 list_del(&bridge->list);
359 mutex_unlock(&bridge_mutex);
360
361 acpi_lock_hp_context();
362 bridge->is_going_away = true;
363 acpi_unlock_hp_context();
364 }
365
366 /**
367 * acpiphp_max_busnr - return the highest reserved bus number under the given bus.
368 * @bus: bus to start search with
369 */
acpiphp_max_busnr(struct pci_bus * bus)370 static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
371 {
372 struct pci_bus *tmp;
373 unsigned char max, n;
374
375 /*
376 * pci_bus_max_busnr will return the highest
377 * reserved busnr for all these children.
378 * that is equivalent to the bus->subordinate
379 * value. We don't want to use the parent's
380 * bus->subordinate value because it could have
381 * padding in it.
382 */
383 max = bus->busn_res.start;
384
385 list_for_each_entry(tmp, &bus->children, node) {
386 n = pci_bus_max_busnr(tmp);
387 if (n > max)
388 max = n;
389 }
390 return max;
391 }
392
acpiphp_set_acpi_region(struct acpiphp_slot * slot)393 static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
394 {
395 struct acpiphp_func *func;
396
397 list_for_each_entry(func, &slot->funcs, sibling) {
398 /* _REG is optional, we don't care about if there is failure */
399 acpi_evaluate_reg(func_to_handle(func),
400 ACPI_ADR_SPACE_PCI_CONFIG,
401 ACPI_REG_CONNECT);
402 }
403 }
404
check_hotplug_bridge(struct acpiphp_slot * slot,struct pci_dev * dev)405 static void check_hotplug_bridge(struct acpiphp_slot *slot, struct pci_dev *dev)
406 {
407 struct acpiphp_func *func;
408
409 /* quirk, or pcie could set it already */
410 if (dev->is_hotplug_bridge)
411 return;
412
413 list_for_each_entry(func, &slot->funcs, sibling) {
414 if (PCI_FUNC(dev->devfn) == func->function) {
415 dev->is_hotplug_bridge = 1;
416 break;
417 }
418 }
419 }
420
acpiphp_rescan_slot(struct acpiphp_slot * slot)421 static int acpiphp_rescan_slot(struct acpiphp_slot *slot)
422 {
423 struct acpiphp_func *func;
424
425 list_for_each_entry(func, &slot->funcs, sibling) {
426 struct acpi_device *adev = func_to_acpi_device(func);
427
428 acpi_bus_scan(adev->handle);
429 if (acpi_device_enumerated(adev))
430 acpi_device_set_power(adev, ACPI_STATE_D0);
431 }
432 return pci_scan_slot(slot->bus, PCI_DEVFN(slot->device, 0));
433 }
434
acpiphp_native_scan_bridge(struct pci_dev * bridge)435 static void acpiphp_native_scan_bridge(struct pci_dev *bridge)
436 {
437 struct pci_bus *bus = bridge->subordinate;
438 struct pci_dev *dev;
439 int max;
440
441 if (!bus)
442 return;
443
444 max = bus->busn_res.start;
445 /* Scan already configured non-hotplug bridges */
446 for_each_pci_bridge(dev, bus) {
447 if (!hotplug_is_native(dev))
448 max = pci_scan_bridge(bus, dev, max, 0);
449 }
450
451 /* Scan non-hotplug bridges that need to be reconfigured */
452 for_each_pci_bridge(dev, bus) {
453 if (hotplug_is_native(dev))
454 continue;
455
456 max = pci_scan_bridge(bus, dev, max, 1);
457 if (dev->subordinate) {
458 pcibios_resource_survey_bus(dev->subordinate);
459 pci_bus_size_bridges(dev->subordinate);
460 pci_bus_assign_resources(dev->subordinate);
461 }
462 }
463 }
464
465 /**
466 * enable_slot - enable, configure a slot
467 * @slot: slot to be enabled
468 * @bridge: true if enable is for the whole bridge (not a single slot)
469 *
470 * This function should be called per *physical slot*,
471 * not per each slot object in ACPI namespace.
472 */
enable_slot(struct acpiphp_slot * slot,bool bridge)473 static void enable_slot(struct acpiphp_slot *slot, bool bridge)
474 {
475 struct pci_dev *dev;
476 struct pci_bus *bus = slot->bus;
477 struct acpiphp_func *func;
478
479 if (bridge && bus->self && hotplug_is_native(bus->self)) {
480 /*
481 * If native hotplug is used, it will take care of hotplug
482 * slot management and resource allocation for hotplug
483 * bridges. However, ACPI hotplug may still be used for
484 * non-hotplug bridges to bring in additional devices such
485 * as a Thunderbolt host controller.
486 */
487 for_each_pci_bridge(dev, bus) {
488 if (PCI_SLOT(dev->devfn) == slot->device)
489 acpiphp_native_scan_bridge(dev);
490 }
491 } else {
492 LIST_HEAD(add_list);
493 int max, pass;
494
495 acpiphp_rescan_slot(slot);
496 max = acpiphp_max_busnr(bus);
497 for (pass = 0; pass < 2; pass++) {
498 for_each_pci_bridge(dev, bus) {
499 if (PCI_SLOT(dev->devfn) != slot->device)
500 continue;
501
502 max = pci_scan_bridge(bus, dev, max, pass);
503 if (pass && dev->subordinate) {
504 check_hotplug_bridge(slot, dev);
505 pcibios_resource_survey_bus(dev->subordinate);
506 __pci_bus_size_bridges(dev->subordinate,
507 &add_list);
508 }
509 }
510 }
511 __pci_bus_assign_resources(bus, &add_list, NULL);
512 }
513
514 acpiphp_sanitize_bus(bus);
515 pcie_bus_configure_settings(bus);
516 acpiphp_set_acpi_region(slot);
517
518 list_for_each_entry(dev, &bus->devices, bus_list) {
519 /* Assume that newly added devices are powered on already. */
520 if (!pci_dev_is_added(dev))
521 dev->current_state = PCI_D0;
522 }
523
524 pci_bus_add_devices(bus);
525
526 slot->flags |= SLOT_ENABLED;
527 list_for_each_entry(func, &slot->funcs, sibling) {
528 dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
529 func->function));
530 if (!dev) {
531 /* Do not set SLOT_ENABLED flag if some funcs
532 are not added. */
533 slot->flags &= ~SLOT_ENABLED;
534 continue;
535 }
536 }
537 }
538
539 /**
540 * disable_slot - disable a slot
541 * @slot: ACPI PHP slot
542 */
disable_slot(struct acpiphp_slot * slot)543 static void disable_slot(struct acpiphp_slot *slot)
544 {
545 struct pci_bus *bus = slot->bus;
546 struct pci_dev *dev, *prev;
547 struct acpiphp_func *func;
548
549 /*
550 * enable_slot() enumerates all functions in this device via
551 * pci_scan_slot(), whether they have associated ACPI hotplug
552 * methods (_EJ0, etc.) or not. Therefore, we remove all functions
553 * here.
554 */
555 list_for_each_entry_safe_reverse(dev, prev, &bus->devices, bus_list)
556 if (PCI_SLOT(dev->devfn) == slot->device)
557 pci_stop_and_remove_bus_device(dev);
558
559 list_for_each_entry(func, &slot->funcs, sibling)
560 acpi_bus_trim(func_to_acpi_device(func));
561
562 slot->flags &= ~SLOT_ENABLED;
563 }
564
slot_no_hotplug(struct acpiphp_slot * slot)565 static bool slot_no_hotplug(struct acpiphp_slot *slot)
566 {
567 struct pci_bus *bus = slot->bus;
568 struct pci_dev *dev;
569
570 list_for_each_entry(dev, &bus->devices, bus_list) {
571 if (PCI_SLOT(dev->devfn) == slot->device && dev->ignore_hotplug)
572 return true;
573 }
574 return false;
575 }
576
577 /**
578 * get_slot_status - get ACPI slot status
579 * @slot: ACPI PHP slot
580 *
581 * If a slot has _STA for each function and if any one of them
582 * returned non-zero status, return it.
583 *
584 * If a slot doesn't have _STA and if any one of its functions'
585 * configuration space is configured, return 0x0f as a _STA.
586 *
587 * Otherwise return 0.
588 */
get_slot_status(struct acpiphp_slot * slot)589 static unsigned int get_slot_status(struct acpiphp_slot *slot)
590 {
591 unsigned long long sta = 0;
592 struct acpiphp_func *func;
593 u32 dvid;
594
595 list_for_each_entry(func, &slot->funcs, sibling) {
596 if (func->flags & FUNC_HAS_STA) {
597 acpi_status status;
598
599 status = acpi_evaluate_integer(func_to_handle(func),
600 "_STA", NULL, &sta);
601 if (ACPI_SUCCESS(status) && sta)
602 break;
603 } else {
604 if (pci_bus_read_dev_vendor_id(slot->bus,
605 PCI_DEVFN(slot->device, func->function),
606 &dvid, 0)) {
607 sta = ACPI_STA_ALL;
608 break;
609 }
610 }
611 }
612
613 if (!sta) {
614 /*
615 * Check for the slot itself since it may be that the
616 * ACPI slot is a device below PCIe upstream port so in
617 * that case it may not even be reachable yet.
618 */
619 if (pci_bus_read_dev_vendor_id(slot->bus,
620 PCI_DEVFN(slot->device, 0), &dvid, 0)) {
621 sta = ACPI_STA_ALL;
622 }
623 }
624
625 return (unsigned int)sta;
626 }
627
device_status_valid(unsigned int sta)628 static inline bool device_status_valid(unsigned int sta)
629 {
630 /*
631 * ACPI spec says that _STA may return bit 0 clear with bit 3 set
632 * if the device is valid but does not require a device driver to be
633 * loaded (Section 6.3.7 of ACPI 5.0A).
634 */
635 unsigned int mask = ACPI_STA_DEVICE_ENABLED | ACPI_STA_DEVICE_FUNCTIONING;
636 return (sta & mask) == mask;
637 }
638
639 /**
640 * trim_stale_devices - remove PCI devices that are not responding.
641 * @dev: PCI device to start walking the hierarchy from.
642 */
trim_stale_devices(struct pci_dev * dev)643 static void trim_stale_devices(struct pci_dev *dev)
644 {
645 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
646 struct pci_bus *bus = dev->subordinate;
647 bool alive = dev->ignore_hotplug;
648
649 if (adev) {
650 acpi_status status;
651 unsigned long long sta;
652
653 status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
654 alive = alive || (ACPI_SUCCESS(status) && device_status_valid(sta));
655 }
656 if (!alive)
657 alive = pci_device_is_present(dev);
658
659 if (!alive) {
660 pci_dev_set_disconnected(dev, NULL);
661 if (pci_has_subordinate(dev))
662 pci_walk_bus(dev->subordinate, pci_dev_set_disconnected,
663 NULL);
664
665 pci_stop_and_remove_bus_device(dev);
666 if (adev)
667 acpi_bus_trim(adev);
668 } else if (bus) {
669 struct pci_dev *child, *tmp;
670
671 /* The device is a bridge. so check the bus below it. */
672 pm_runtime_get_sync(&dev->dev);
673 list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
674 trim_stale_devices(child);
675
676 pm_runtime_put(&dev->dev);
677 }
678 }
679
680 /**
681 * acpiphp_check_bridge - re-enumerate devices
682 * @bridge: where to begin re-enumeration
683 *
684 * Iterate over all slots under this bridge and make sure that if a
685 * card is present they are enabled, and if not they are disabled.
686 */
acpiphp_check_bridge(struct acpiphp_bridge * bridge)687 static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
688 {
689 struct acpiphp_slot *slot;
690
691 /* Bail out if the bridge is going away. */
692 if (bridge->is_going_away)
693 return;
694
695 if (bridge->pci_dev)
696 pm_runtime_get_sync(&bridge->pci_dev->dev);
697
698 list_for_each_entry(slot, &bridge->slots, node) {
699 struct pci_bus *bus = slot->bus;
700 struct pci_dev *dev, *tmp;
701
702 if (slot_no_hotplug(slot)) {
703 ; /* do nothing */
704 } else if (device_status_valid(get_slot_status(slot))) {
705 /* remove stale devices if any */
706 list_for_each_entry_safe_reverse(dev, tmp,
707 &bus->devices, bus_list)
708 if (PCI_SLOT(dev->devfn) == slot->device)
709 trim_stale_devices(dev);
710
711 /* configure all functions */
712 enable_slot(slot, true);
713 } else {
714 disable_slot(slot);
715 }
716 }
717
718 if (bridge->pci_dev)
719 pm_runtime_put(&bridge->pci_dev->dev);
720 }
721
722 /*
723 * Remove devices for which we could not assign resources, call
724 * arch specific code to fix-up the bus
725 */
acpiphp_sanitize_bus(struct pci_bus * bus)726 static void acpiphp_sanitize_bus(struct pci_bus *bus)
727 {
728 struct pci_dev *dev, *tmp;
729 int i;
730 unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
731
732 list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
733 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
734 struct resource *res = &dev->resource[i];
735 if ((res->flags & type_mask) && !res->start &&
736 res->end) {
737 /* Could not assign a required resources
738 * for this device, remove it */
739 pci_stop_and_remove_bus_device(dev);
740 break;
741 }
742 }
743 }
744 }
745
746 /*
747 * ACPI event handlers
748 */
749
acpiphp_check_host_bridge(struct acpi_device * adev)750 void acpiphp_check_host_bridge(struct acpi_device *adev)
751 {
752 struct acpiphp_bridge *bridge = NULL;
753
754 acpi_lock_hp_context();
755 if (adev->hp) {
756 bridge = to_acpiphp_root_context(adev->hp)->root_bridge;
757 if (bridge)
758 get_bridge(bridge);
759 }
760 acpi_unlock_hp_context();
761 if (bridge) {
762 pci_lock_rescan_remove();
763
764 acpiphp_check_bridge(bridge);
765
766 pci_unlock_rescan_remove();
767 put_bridge(bridge);
768 }
769 }
770
771 static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
772
hotplug_event(u32 type,struct acpiphp_context * context)773 static void hotplug_event(u32 type, struct acpiphp_context *context)
774 {
775 acpi_handle handle = context->hp.self->handle;
776 struct acpiphp_func *func = &context->func;
777 struct acpiphp_slot *slot = func->slot;
778 struct acpiphp_bridge *bridge;
779
780 acpi_lock_hp_context();
781 bridge = context->bridge;
782 if (bridge)
783 get_bridge(bridge);
784
785 acpi_unlock_hp_context();
786
787 pci_lock_rescan_remove();
788
789 switch (type) {
790 case ACPI_NOTIFY_BUS_CHECK:
791 /* bus re-enumerate */
792 acpi_handle_debug(handle, "Bus check in %s()\n", __func__);
793 if (bridge)
794 acpiphp_check_bridge(bridge);
795 else if (!(slot->flags & SLOT_IS_GOING_AWAY))
796 enable_slot(slot, false);
797
798 break;
799
800 case ACPI_NOTIFY_DEVICE_CHECK:
801 /* device check */
802 acpi_handle_debug(handle, "Device check in %s()\n", __func__);
803 if (bridge) {
804 acpiphp_check_bridge(bridge);
805 } else if (!(slot->flags & SLOT_IS_GOING_AWAY)) {
806 /*
807 * Check if anything has changed in the slot and rescan
808 * from the parent if that's the case.
809 */
810 if (acpiphp_rescan_slot(slot))
811 acpiphp_check_bridge(func->parent);
812 }
813 break;
814
815 case ACPI_NOTIFY_EJECT_REQUEST:
816 /* request device eject */
817 acpi_handle_debug(handle, "Eject request in %s()\n", __func__);
818 acpiphp_disable_and_eject_slot(slot);
819 break;
820 }
821
822 pci_unlock_rescan_remove();
823 if (bridge)
824 put_bridge(bridge);
825 }
826
acpiphp_hotplug_notify(struct acpi_device * adev,u32 type)827 static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type)
828 {
829 struct acpiphp_context *context;
830
831 context = acpiphp_grab_context(adev);
832 if (!context)
833 return -ENODATA;
834
835 hotplug_event(type, context);
836 acpiphp_let_context_go(context);
837 return 0;
838 }
839
840 /**
841 * acpiphp_enumerate_slots - Enumerate PCI slots for a given bus.
842 * @bus: PCI bus to enumerate the slots for.
843 *
844 * A "slot" is an object associated with a PCI device number. All functions
845 * (PCI devices) with the same bus and device number belong to the same slot.
846 */
acpiphp_enumerate_slots(struct pci_bus * bus)847 void acpiphp_enumerate_slots(struct pci_bus *bus)
848 {
849 struct acpiphp_bridge *bridge;
850 struct acpi_device *adev;
851 acpi_handle handle;
852 acpi_status status;
853
854 if (acpiphp_disabled)
855 return;
856
857 adev = ACPI_COMPANION(bus->bridge);
858 if (!adev)
859 return;
860
861 handle = adev->handle;
862 bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
863 if (!bridge)
864 return;
865
866 INIT_LIST_HEAD(&bridge->slots);
867 kref_init(&bridge->ref);
868 bridge->pci_dev = pci_dev_get(bus->self);
869 bridge->pci_bus = bus;
870
871 /*
872 * Grab a ref to the subordinate PCI bus in case the bus is
873 * removed via PCI core logical hotplug. The ref pins the bus
874 * (which we access during module unload).
875 */
876 get_device(&bus->dev);
877
878 acpi_lock_hp_context();
879 if (pci_is_root_bus(bridge->pci_bus)) {
880 struct acpiphp_root_context *root_context;
881
882 root_context = kzalloc(sizeof(*root_context), GFP_KERNEL);
883 if (!root_context)
884 goto err;
885
886 root_context->root_bridge = bridge;
887 acpi_set_hp_context(adev, &root_context->hp);
888 } else {
889 struct acpiphp_context *context;
890
891 /*
892 * This bridge should have been registered as a hotplug function
893 * under its parent, so the context should be there, unless the
894 * parent is going to be handled by pciehp, in which case this
895 * bridge is not interesting to us either.
896 */
897 context = acpiphp_get_context(adev);
898 if (!context)
899 goto err;
900
901 bridge->context = context;
902 context->bridge = bridge;
903 /* Get a reference to the parent bridge. */
904 get_bridge(context->func.parent);
905 }
906 acpi_unlock_hp_context();
907
908 /* Must be added to the list prior to calling acpiphp_add_context(). */
909 mutex_lock(&bridge_mutex);
910 list_add(&bridge->list, &bridge_list);
911 mutex_unlock(&bridge_mutex);
912
913 /* register all slot objects under this bridge */
914 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
915 acpiphp_add_context, NULL, bridge, NULL);
916 if (ACPI_FAILURE(status)) {
917 acpi_handle_err(handle, "failed to register slots\n");
918 cleanup_bridge(bridge);
919 put_bridge(bridge);
920 }
921 return;
922
923 err:
924 acpi_unlock_hp_context();
925 put_device(&bus->dev);
926 pci_dev_put(bridge->pci_dev);
927 kfree(bridge);
928 }
929
acpiphp_drop_bridge(struct acpiphp_bridge * bridge)930 static void acpiphp_drop_bridge(struct acpiphp_bridge *bridge)
931 {
932 if (pci_is_root_bus(bridge->pci_bus)) {
933 struct acpiphp_root_context *root_context;
934 struct acpi_device *adev;
935
936 acpi_lock_hp_context();
937 adev = ACPI_COMPANION(bridge->pci_bus->bridge);
938 root_context = to_acpiphp_root_context(adev->hp);
939 adev->hp = NULL;
940 acpi_unlock_hp_context();
941 kfree(root_context);
942 }
943 cleanup_bridge(bridge);
944 put_bridge(bridge);
945 }
946
947 /**
948 * acpiphp_remove_slots - Remove slot objects associated with a given bus.
949 * @bus: PCI bus to remove the slot objects for.
950 */
acpiphp_remove_slots(struct pci_bus * bus)951 void acpiphp_remove_slots(struct pci_bus *bus)
952 {
953 struct acpiphp_bridge *bridge;
954
955 if (acpiphp_disabled)
956 return;
957
958 mutex_lock(&bridge_mutex);
959 list_for_each_entry(bridge, &bridge_list, list)
960 if (bridge->pci_bus == bus) {
961 mutex_unlock(&bridge_mutex);
962 acpiphp_drop_bridge(bridge);
963 return;
964 }
965
966 mutex_unlock(&bridge_mutex);
967 }
968
969 /**
970 * acpiphp_enable_slot - power on slot
971 * @slot: ACPI PHP slot
972 */
acpiphp_enable_slot(struct acpiphp_slot * slot)973 int acpiphp_enable_slot(struct acpiphp_slot *slot)
974 {
975 pci_lock_rescan_remove();
976
977 if (slot->flags & SLOT_IS_GOING_AWAY) {
978 pci_unlock_rescan_remove();
979 return -ENODEV;
980 }
981
982 /* configure all functions */
983 if (!(slot->flags & SLOT_ENABLED))
984 enable_slot(slot, false);
985
986 pci_unlock_rescan_remove();
987 return 0;
988 }
989
990 /**
991 * acpiphp_disable_and_eject_slot - power off and eject slot
992 * @slot: ACPI PHP slot
993 */
acpiphp_disable_and_eject_slot(struct acpiphp_slot * slot)994 static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
995 {
996 struct acpiphp_func *func;
997
998 if (slot->flags & SLOT_IS_GOING_AWAY)
999 return -ENODEV;
1000
1001 /* unconfigure all functions */
1002 disable_slot(slot);
1003
1004 list_for_each_entry(func, &slot->funcs, sibling)
1005 if (func->flags & FUNC_HAS_EJ0) {
1006 acpi_handle handle = func_to_handle(func);
1007
1008 if (ACPI_FAILURE(acpi_evaluate_ej0(handle)))
1009 acpi_handle_err(handle, "_EJ0 failed\n");
1010
1011 break;
1012 }
1013
1014 return 0;
1015 }
1016
acpiphp_disable_slot(struct acpiphp_slot * slot)1017 int acpiphp_disable_slot(struct acpiphp_slot *slot)
1018 {
1019 int ret;
1020
1021 /*
1022 * Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
1023 * acpiphp_disable_and_eject_slot() will be synchronized properly.
1024 */
1025 acpi_scan_lock_acquire();
1026 pci_lock_rescan_remove();
1027 ret = acpiphp_disable_and_eject_slot(slot);
1028 pci_unlock_rescan_remove();
1029 acpi_scan_lock_release();
1030 return ret;
1031 }
1032
1033 /*
1034 * slot enabled: 1
1035 * slot disabled: 0
1036 */
acpiphp_get_power_status(struct acpiphp_slot * slot)1037 u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
1038 {
1039 return (slot->flags & SLOT_ENABLED);
1040 }
1041
1042 /*
1043 * latch open: 1
1044 * latch closed: 0
1045 */
acpiphp_get_latch_status(struct acpiphp_slot * slot)1046 u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
1047 {
1048 return !(get_slot_status(slot) & ACPI_STA_DEVICE_UI);
1049 }
1050
1051 /*
1052 * adapter presence : 1
1053 * absence : 0
1054 */
acpiphp_get_adapter_status(struct acpiphp_slot * slot)1055 u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
1056 {
1057 return !!get_slot_status(slot);
1058 }
1059
