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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// 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
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
139unlock:
140 acpi_unlock_hp_context();
141 return context;
142}
143
144static void acpiphp_let_context_go(struct acpiphp_context *context)
145{
146 put_bridge(context->func.parent);
147}
148
149static 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 */
189static 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 */
226static 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
338static 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 */
370static 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
393static 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
405static 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
421static 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
435static 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 */
473static 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 pci_dev_put(dev);
537 }
538}
539
540/**
541 * disable_slot - disable a slot
542 * @slot: ACPI PHP slot
543 */
544static void disable_slot(struct acpiphp_slot *slot)
545{
546 struct pci_bus *bus = slot->bus;
547 struct pci_dev *dev, *prev;
548 struct acpiphp_func *func;
549
550 /*
551 * enable_slot() enumerates all functions in this device via
552 * pci_scan_slot(), whether they have associated ACPI hotplug
553 * methods (_EJ0, etc.) or not. Therefore, we remove all functions
554 * here.
555 */
556 list_for_each_entry_safe_reverse(dev, prev, &bus->devices, bus_list)
557 if (PCI_SLOT(dev->devfn) == slot->device)
558 pci_stop_and_remove_bus_device(dev);
559
560 list_for_each_entry(func, &slot->funcs, sibling)
561 acpi_bus_trim(func_to_acpi_device(func));
562
563 slot->flags &= ~SLOT_ENABLED;
564}
565
566static bool slot_no_hotplug(struct acpiphp_slot *slot)
567{
568 struct pci_bus *bus = slot->bus;
569 struct pci_dev *dev;
570
571 list_for_each_entry(dev, &bus->devices, bus_list) {
572 if (PCI_SLOT(dev->devfn) == slot->device && dev->ignore_hotplug)
573 return true;
574 }
575 return false;
576}
577
578/**
579 * get_slot_status - get ACPI slot status
580 * @slot: ACPI PHP slot
581 *
582 * If a slot has _STA for each function and if any one of them
583 * returned non-zero status, return it.
584 *
585 * If a slot doesn't have _STA and if any one of its functions'
586 * configuration space is configured, return 0x0f as a _STA.
587 *
588 * Otherwise return 0.
589 */
590static unsigned int get_slot_status(struct acpiphp_slot *slot)
591{
592 unsigned long long sta = 0;
593 struct acpiphp_func *func;
594 u32 dvid;
595
596 list_for_each_entry(func, &slot->funcs, sibling) {
597 if (func->flags & FUNC_HAS_STA) {
598 acpi_status status;
599
600 status = acpi_evaluate_integer(func_to_handle(func),
601 "_STA", NULL, &sta);
602 if (ACPI_SUCCESS(status) && sta)
603 break;
604 } else {
605 if (pci_bus_read_dev_vendor_id(slot->bus,
606 PCI_DEVFN(slot->device, func->function),
607 &dvid, 0)) {
608 sta = ACPI_STA_ALL;
609 break;
610 }
611 }
612 }
613
614 if (!sta) {
615 /*
616 * Check for the slot itself since it may be that the
617 * ACPI slot is a device below PCIe upstream port so in
618 * that case it may not even be reachable yet.
619 */
620 if (pci_bus_read_dev_vendor_id(slot->bus,
621 PCI_DEVFN(slot->device, 0), &dvid, 0)) {
622 sta = ACPI_STA_ALL;
623 }
624 }
625
626 return (unsigned int)sta;
627}
628
629static inline bool device_status_valid(unsigned int sta)
630{
631 /*
632 * ACPI spec says that _STA may return bit 0 clear with bit 3 set
633 * if the device is valid but does not require a device driver to be
634 * loaded (Section 6.3.7 of ACPI 5.0A).
635 */
636 unsigned int mask = ACPI_STA_DEVICE_ENABLED | ACPI_STA_DEVICE_FUNCTIONING;
637 return (sta & mask) == mask;
638}
639
640/**
641 * trim_stale_devices - remove PCI devices that are not responding.
642 * @dev: PCI device to start walking the hierarchy from.
643 */
644static void trim_stale_devices(struct pci_dev *dev)
645{
646 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
647 struct pci_bus *bus = dev->subordinate;
648 bool alive = dev->ignore_hotplug;
649
650 if (adev) {
651 acpi_status status;
652 unsigned long long sta;
653
654 status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
655 alive = alive || (ACPI_SUCCESS(status) && device_status_valid(sta));
656 }
657 if (!alive)
658 alive = pci_device_is_present(dev);
659
660 if (!alive) {
661 pci_dev_set_disconnected(dev, NULL);
662 if (pci_has_subordinate(dev))
663 pci_walk_bus(dev->subordinate, pci_dev_set_disconnected,
664 NULL);
665
666 pci_stop_and_remove_bus_device(dev);
667 if (adev)
668 acpi_bus_trim(adev);
669 } else if (bus) {
670 struct pci_dev *child, *tmp;
671
672 /* The device is a bridge. so check the bus below it. */
673 pm_runtime_get_sync(&dev->dev);
674 list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
675 trim_stale_devices(child);
676
677 pm_runtime_put(&dev->dev);
678 }
679}
680
681/**
682 * acpiphp_check_bridge - re-enumerate devices
683 * @bridge: where to begin re-enumeration
684 *
685 * Iterate over all slots under this bridge and make sure that if a
686 * card is present they are enabled, and if not they are disabled.
687 */
688static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
689{
690 struct acpiphp_slot *slot;
691
692 /* Bail out if the bridge is going away. */
693 if (bridge->is_going_away)
694 return;
695
696 if (bridge->pci_dev)
697 pm_runtime_get_sync(&bridge->pci_dev->dev);
698
699 list_for_each_entry(slot, &bridge->slots, node) {
700 struct pci_bus *bus = slot->bus;
701 struct pci_dev *dev, *tmp;
702
703 if (slot_no_hotplug(slot)) {
704 ; /* do nothing */
705 } else if (device_status_valid(get_slot_status(slot))) {
706 /* remove stale devices if any */
707 list_for_each_entry_safe_reverse(dev, tmp,
708 &bus->devices, bus_list)
709 if (PCI_SLOT(dev->devfn) == slot->device)
710 trim_stale_devices(dev);
711
712 /* configure all functions */
713 enable_slot(slot, true);
714 } else {
715 disable_slot(slot);
716 }
717 }
718
719 if (bridge->pci_dev)
720 pm_runtime_put(&bridge->pci_dev->dev);
721}
722
723/*
724 * Remove devices for which we could not assign resources, call
725 * arch specific code to fix-up the bus
726 */
727static void acpiphp_sanitize_bus(struct pci_bus *bus)
728{
729 struct pci_dev *dev, *tmp;
730 int i;
731 unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
732
733 list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
734 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
735 struct resource *res = &dev->resource[i];
736 if ((res->flags & type_mask) && !res->start &&
737 res->end) {
738 /* Could not assign a required resources
739 * for this device, remove it */
740 pci_stop_and_remove_bus_device(dev);
741 break;
742 }
743 }
744 }
745}
746
747/*
748 * ACPI event handlers
749 */
750
751void acpiphp_check_host_bridge(struct acpi_device *adev)
752{
753 struct acpiphp_bridge *bridge = NULL;
754
755 acpi_lock_hp_context();
756 if (adev->hp) {
757 bridge = to_acpiphp_root_context(adev->hp)->root_bridge;
758 if (bridge)
759 get_bridge(bridge);
760 }
761 acpi_unlock_hp_context();
762 if (bridge) {
763 pci_lock_rescan_remove();
764
765 acpiphp_check_bridge(bridge);
766
767 pci_unlock_rescan_remove();
768 put_bridge(bridge);
769 }
770}
771
772static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
773
774static void hotplug_event(u32 type, struct acpiphp_context *context)
775{
776 acpi_handle handle = context->hp.self->handle;
777 struct acpiphp_func *func = &context->func;
778 struct acpiphp_slot *slot = func->slot;
779 struct acpiphp_bridge *bridge;
780
781 acpi_lock_hp_context();
782 bridge = context->bridge;
783 if (bridge)
784 get_bridge(bridge);
785
786 acpi_unlock_hp_context();
787
788 pci_lock_rescan_remove();
789
790 switch (type) {
791 case ACPI_NOTIFY_BUS_CHECK:
792 /* bus re-enumerate */
793 acpi_handle_debug(handle, "Bus check in %s()\n", __func__);
794 if (bridge)
795 acpiphp_check_bridge(bridge);
796 else if (!(slot->flags & SLOT_IS_GOING_AWAY))
797 enable_slot(slot, false);
798
799 break;
800
801 case ACPI_NOTIFY_DEVICE_CHECK:
802 /* device check */
803 acpi_handle_debug(handle, "Device check in %s()\n", __func__);
804 if (bridge) {
805 acpiphp_check_bridge(bridge);
806 } else if (!(slot->flags & SLOT_IS_GOING_AWAY)) {
807 /*
808 * Check if anything has changed in the slot and rescan
809 * from the parent if that's the case.
810 */
811 if (acpiphp_rescan_slot(slot))
812 acpiphp_check_bridge(func->parent);
813 }
814 break;
815
816 case ACPI_NOTIFY_EJECT_REQUEST:
817 /* request device eject */
818 acpi_handle_debug(handle, "Eject request in %s()\n", __func__);
819 acpiphp_disable_and_eject_slot(slot);
820 break;
821 }
822
823 pci_unlock_rescan_remove();
824 if (bridge)
825 put_bridge(bridge);
826}
827
828static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type)
829{
830 struct acpiphp_context *context;
831
832 context = acpiphp_grab_context(adev);
833 if (!context)
834 return -ENODATA;
835
836 hotplug_event(type, context);
837 acpiphp_let_context_go(context);
838 return 0;
839}
840
841/**
842 * acpiphp_enumerate_slots - Enumerate PCI slots for a given bus.
843 * @bus: PCI bus to enumerate the slots for.
844 *
845 * A "slot" is an object associated with a PCI device number. All functions
846 * (PCI devices) with the same bus and device number belong to the same slot.
847 */
848void acpiphp_enumerate_slots(struct pci_bus *bus)
849{
850 struct acpiphp_bridge *bridge;
851 struct acpi_device *adev;
852 acpi_handle handle;
853 acpi_status status;
854
855 if (acpiphp_disabled)
856 return;
857
858 adev = ACPI_COMPANION(bus->bridge);
859 if (!adev)
860 return;
861
862 handle = adev->handle;
863 bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
864 if (!bridge)
865 return;
866
867 INIT_LIST_HEAD(&bridge->slots);
868 kref_init(&bridge->ref);
869 bridge->pci_dev = pci_dev_get(bus->self);
870 bridge->pci_bus = bus;
871
872 /*
873 * Grab a ref to the subordinate PCI bus in case the bus is
874 * removed via PCI core logical hotplug. The ref pins the bus
875 * (which we access during module unload).
876 */
877 get_device(&bus->dev);
878
879 acpi_lock_hp_context();
880 if (pci_is_root_bus(bridge->pci_bus)) {
881 struct acpiphp_root_context *root_context;
882
883 root_context = kzalloc(sizeof(*root_context), GFP_KERNEL);
884 if (!root_context)
885 goto err;
886
887 root_context->root_bridge = bridge;
888 acpi_set_hp_context(adev, &root_context->hp);
889 } else {
890 struct acpiphp_context *context;
891
892 /*
893 * This bridge should have been registered as a hotplug function
894 * under its parent, so the context should be there, unless the
895 * parent is going to be handled by pciehp, in which case this
896 * bridge is not interesting to us either.
897 */
898 context = acpiphp_get_context(adev);
899 if (!context)
900 goto err;
901
902 bridge->context = context;
903 context->bridge = bridge;
904 /* Get a reference to the parent bridge. */
905 get_bridge(context->func.parent);
906 }
907 acpi_unlock_hp_context();
908
909 /* Must be added to the list prior to calling acpiphp_add_context(). */
910 mutex_lock(&bridge_mutex);
911 list_add(&bridge->list, &bridge_list);
912 mutex_unlock(&bridge_mutex);
913
914 /* register all slot objects under this bridge */
915 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
916 acpiphp_add_context, NULL, bridge, NULL);
917 if (ACPI_FAILURE(status)) {
918 acpi_handle_err(handle, "failed to register slots\n");
919 cleanup_bridge(bridge);
920 put_bridge(bridge);
921 }
922 return;
923
924 err:
925 acpi_unlock_hp_context();
926 put_device(&bus->dev);
927 pci_dev_put(bridge->pci_dev);
928 kfree(bridge);
929}
930
931static void acpiphp_drop_bridge(struct acpiphp_bridge *bridge)
932{
933 if (pci_is_root_bus(bridge->pci_bus)) {
934 struct acpiphp_root_context *root_context;
935 struct acpi_device *adev;
936
937 acpi_lock_hp_context();
938 adev = ACPI_COMPANION(bridge->pci_bus->bridge);
939 root_context = to_acpiphp_root_context(adev->hp);
940 adev->hp = NULL;
941 acpi_unlock_hp_context();
942 kfree(root_context);
943 }
944 cleanup_bridge(bridge);
945 put_bridge(bridge);
946}
947
948/**
949 * acpiphp_remove_slots - Remove slot objects associated with a given bus.
950 * @bus: PCI bus to remove the slot objects for.
951 */
952void acpiphp_remove_slots(struct pci_bus *bus)
953{
954 struct acpiphp_bridge *bridge;
955
956 if (acpiphp_disabled)
957 return;
958
959 mutex_lock(&bridge_mutex);
960 list_for_each_entry(bridge, &bridge_list, list)
961 if (bridge->pci_bus == bus) {
962 mutex_unlock(&bridge_mutex);
963 acpiphp_drop_bridge(bridge);
964 return;
965 }
966
967 mutex_unlock(&bridge_mutex);
968}
969
970/**
971 * acpiphp_enable_slot - power on slot
972 * @slot: ACPI PHP slot
973 */
974int acpiphp_enable_slot(struct acpiphp_slot *slot)
975{
976 pci_lock_rescan_remove();
977
978 if (slot->flags & SLOT_IS_GOING_AWAY) {
979 pci_unlock_rescan_remove();
980 return -ENODEV;
981 }
982
983 /* configure all functions */
984 if (!(slot->flags & SLOT_ENABLED))
985 enable_slot(slot, false);
986
987 pci_unlock_rescan_remove();
988 return 0;
989}
990
991/**
992 * acpiphp_disable_and_eject_slot - power off and eject slot
993 * @slot: ACPI PHP slot
994 */
995static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
996{
997 struct acpiphp_func *func;
998
999 if (slot->flags & SLOT_IS_GOING_AWAY)
1000 return -ENODEV;
1001
1002 /* unconfigure all functions */
1003 disable_slot(slot);
1004
1005 list_for_each_entry(func, &slot->funcs, sibling)
1006 if (func->flags & FUNC_HAS_EJ0) {
1007 acpi_handle handle = func_to_handle(func);
1008
1009 if (ACPI_FAILURE(acpi_evaluate_ej0(handle)))
1010 acpi_handle_err(handle, "_EJ0 failed\n");
1011
1012 break;
1013 }
1014
1015 return 0;
1016}
1017
1018int acpiphp_disable_slot(struct acpiphp_slot *slot)
1019{
1020 int ret;
1021
1022 /*
1023 * Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
1024 * acpiphp_disable_and_eject_slot() will be synchronized properly.
1025 */
1026 acpi_scan_lock_acquire();
1027 pci_lock_rescan_remove();
1028 ret = acpiphp_disable_and_eject_slot(slot);
1029 pci_unlock_rescan_remove();
1030 acpi_scan_lock_release();
1031 return ret;
1032}
1033
1034/*
1035 * slot enabled: 1
1036 * slot disabled: 0
1037 */
1038u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
1039{
1040 return (slot->flags & SLOT_ENABLED);
1041}
1042
1043/*
1044 * latch open: 1
1045 * latch closed: 0
1046 */
1047u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
1048{
1049 return !(get_slot_status(slot) & ACPI_STA_DEVICE_UI);
1050}
1051
1052/*
1053 * adapter presence : 1
1054 * absence : 0
1055 */
1056u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
1057{
1058 return !!get_slot_status(slot);
1059}