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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 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 acpi_device *adev = acpi_fetch_acpi_dev(handle);
230 struct acpiphp_bridge *bridge = data;
231 struct acpiphp_context *context;
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 if (!adev)
242 return AE_OK;
243
244 status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
245 if (ACPI_FAILURE(status)) {
246 if (status != AE_NOT_FOUND)
247 acpi_handle_warn(handle,
248 "can't evaluate _ADR (%#x)\n", status);
249 return AE_OK;
250 }
251
252 device = (adr >> 16) & 0xffff;
253 function = adr & 0xffff;
254
255 acpi_lock_hp_context();
256 context = acpiphp_init_context(adev);
257 if (!context) {
258 acpi_unlock_hp_context();
259 acpi_handle_err(handle, "No hotplug context\n");
260 return AE_NOT_EXIST;
261 }
262 newfunc = &context->func;
263 newfunc->function = function;
264 newfunc->parent = bridge;
265 acpi_unlock_hp_context();
266
267 /*
268 * If this is a dock device, its _EJ0 should be executed by the dock
269 * notify handler after calling _DCK.
270 */
271 if (!is_dock_device(adev) && acpi_has_method(handle, "_EJ0"))
272 newfunc->flags = FUNC_HAS_EJ0;
273
274 if (acpi_has_method(handle, "_STA"))
275 newfunc->flags |= FUNC_HAS_STA;
276
277 /* search for objects that share the same slot */
278 list_for_each_entry(slot, &bridge->slots, node)
279 if (slot->device == device)
280 goto slot_found;
281
282 slot = kzalloc(sizeof(struct acpiphp_slot), GFP_KERNEL);
283 if (!slot) {
284 acpi_lock_hp_context();
285 acpiphp_put_context(context);
286 acpi_unlock_hp_context();
287 return AE_NO_MEMORY;
288 }
289
290 slot->bus = bridge->pci_bus;
291 slot->device = device;
292 INIT_LIST_HEAD(&slot->funcs);
293
294 list_add_tail(&slot->node, &bridge->slots);
295
296 /*
297 * Expose slots to user space for functions that have _EJ0 or _RMV or
298 * are located in dock stations. Do not expose them for devices handled
299 * by the native PCIe hotplug (PCIeHP) or standard PCI hotplug
300 * (SHPCHP), because that code is supposed to expose slots to user
301 * space in those cases.
302 */
303 if ((acpi_pci_check_ejectable(pbus, handle) || is_dock_device(adev))
304 && !(pdev && hotplug_is_native(pdev))) {
305 unsigned long long sun;
306 int retval;
307
308 bridge->nr_slots++;
309 status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
310 if (ACPI_FAILURE(status))
311 sun = bridge->nr_slots;
312
313 pr_debug("found ACPI PCI Hotplug slot %llu at PCI %04x:%02x:%02x\n",
314 sun, pci_domain_nr(pbus), pbus->number, device);
315
316 retval = acpiphp_register_hotplug_slot(slot, sun);
317 if (retval) {
318 slot->slot = NULL;
319 bridge->nr_slots--;
320 if (retval == -EBUSY)
321 pr_warn("Slot %llu already registered by another hotplug driver\n", sun);
322 else
323 pr_warn("acpiphp_register_hotplug_slot failed (err code = 0x%x)\n", retval);
324 }
325 /* Even if the slot registration fails, we can still use it. */
326 }
327
328 slot_found:
329 newfunc->slot = slot;
330 list_add_tail(&newfunc->sibling, &slot->funcs);
331
332 if (pci_bus_read_dev_vendor_id(pbus, PCI_DEVFN(device, function),
333 &val, 60*1000))
334 slot->flags |= SLOT_ENABLED;
335
336 return AE_OK;
337}
338
339static void cleanup_bridge(struct acpiphp_bridge *bridge)
340{
341 struct acpiphp_slot *slot;
342 struct acpiphp_func *func;
343
344 list_for_each_entry(slot, &bridge->slots, node) {
345 list_for_each_entry(func, &slot->funcs, sibling) {
346 struct acpi_device *adev = func_to_acpi_device(func);
347
348 acpi_lock_hp_context();
349 adev->hp->notify = NULL;
350 adev->hp->fixup = NULL;
351 acpi_unlock_hp_context();
352 }
353 slot->flags |= SLOT_IS_GOING_AWAY;
354 if (slot->slot)
355 acpiphp_unregister_hotplug_slot(slot);
356 }
357
358 mutex_lock(&bridge_mutex);
359 list_del(&bridge->list);
360 mutex_unlock(&bridge_mutex);
361
362 acpi_lock_hp_context();
363 bridge->is_going_away = true;
364 acpi_unlock_hp_context();
365}
366
367/**
368 * acpiphp_max_busnr - return the highest reserved bus number under the given bus.
369 * @bus: bus to start search with
370 */
371static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
372{
373 struct pci_bus *tmp;
374 unsigned char max, n;
375
376 /*
377 * pci_bus_max_busnr will return the highest
378 * reserved busnr for all these children.
379 * that is equivalent to the bus->subordinate
380 * value. We don't want to use the parent's
381 * bus->subordinate value because it could have
382 * padding in it.
383 */
384 max = bus->busn_res.start;
385
386 list_for_each_entry(tmp, &bus->children, node) {
387 n = pci_bus_max_busnr(tmp);
388 if (n > max)
389 max = n;
390 }
391 return max;
392}
393
394static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
395{
396 struct acpiphp_func *func;
397
398 list_for_each_entry(func, &slot->funcs, sibling) {
399 /* _REG is optional, we don't care about if there is failure */
400 acpi_evaluate_reg(func_to_handle(func),
401 ACPI_ADR_SPACE_PCI_CONFIG,
402 ACPI_REG_CONNECT);
403 }
404}
405
406static void check_hotplug_bridge(struct acpiphp_slot *slot, struct pci_dev *dev)
407{
408 struct acpiphp_func *func;
409
410 /* quirk, or pcie could set it already */
411 if (dev->is_hotplug_bridge)
412 return;
413
414 /*
415 * In the PCIe case, only Root Ports and Downstream Ports are capable of
416 * accommodating hotplug devices, so avoid marking Upstream Ports as
417 * "hotplug bridges".
418 */
419 if (pci_is_pcie(dev) && pci_pcie_type(dev) == PCI_EXP_TYPE_UPSTREAM)
420 return;
421
422 list_for_each_entry(func, &slot->funcs, sibling) {
423 if (PCI_FUNC(dev->devfn) == func->function) {
424 dev->is_hotplug_bridge = 1;
425 break;
426 }
427 }
428}
429
430static int acpiphp_rescan_slot(struct acpiphp_slot *slot)
431{
432 struct acpiphp_func *func;
433
434 list_for_each_entry(func, &slot->funcs, sibling) {
435 struct acpi_device *adev = func_to_acpi_device(func);
436
437 acpi_bus_scan(adev->handle);
438 if (acpi_device_enumerated(adev))
439 acpi_device_set_power(adev, ACPI_STATE_D0);
440 }
441 return pci_scan_slot(slot->bus, PCI_DEVFN(slot->device, 0));
442}
443
444static void acpiphp_native_scan_bridge(struct pci_dev *bridge)
445{
446 struct pci_bus *bus = bridge->subordinate;
447 struct pci_dev *dev;
448 int max;
449
450 if (!bus)
451 return;
452
453 max = bus->busn_res.start;
454 /* Scan already configured non-hotplug bridges */
455 for_each_pci_bridge(dev, bus) {
456 if (!hotplug_is_native(dev))
457 max = pci_scan_bridge(bus, dev, max, 0);
458 }
459
460 /* Scan non-hotplug bridges that need to be reconfigured */
461 for_each_pci_bridge(dev, bus) {
462 if (hotplug_is_native(dev))
463 continue;
464
465 max = pci_scan_bridge(bus, dev, max, 1);
466 if (dev->subordinate) {
467 pcibios_resource_survey_bus(dev->subordinate);
468 pci_bus_size_bridges(dev->subordinate);
469 pci_bus_assign_resources(dev->subordinate);
470 }
471 }
472}
473
474/**
475 * enable_slot - enable, configure a slot
476 * @slot: slot to be enabled
477 * @bridge: true if enable is for the whole bridge (not a single slot)
478 *
479 * This function should be called per *physical slot*,
480 * not per each slot object in ACPI namespace.
481 */
482static void enable_slot(struct acpiphp_slot *slot, bool bridge)
483{
484 struct pci_dev *dev;
485 struct pci_bus *bus = slot->bus;
486 struct acpiphp_func *func;
487
488 if (bridge && bus->self && hotplug_is_native(bus->self)) {
489 /*
490 * If native hotplug is used, it will take care of hotplug
491 * slot management and resource allocation for hotplug
492 * bridges. However, ACPI hotplug may still be used for
493 * non-hotplug bridges to bring in additional devices such
494 * as a Thunderbolt host controller.
495 */
496 for_each_pci_bridge(dev, bus) {
497 if (PCI_SLOT(dev->devfn) == slot->device)
498 acpiphp_native_scan_bridge(dev);
499 }
500 } else {
501 LIST_HEAD(add_list);
502 int max, pass;
503
504 acpiphp_rescan_slot(slot);
505 max = acpiphp_max_busnr(bus);
506 for (pass = 0; pass < 2; pass++) {
507 for_each_pci_bridge(dev, bus) {
508 if (PCI_SLOT(dev->devfn) != slot->device)
509 continue;
510
511 max = pci_scan_bridge(bus, dev, max, pass);
512 if (pass && dev->subordinate) {
513 check_hotplug_bridge(slot, dev);
514 pcibios_resource_survey_bus(dev->subordinate);
515 __pci_bus_size_bridges(dev->subordinate,
516 &add_list);
517 }
518 }
519 }
520 __pci_bus_assign_resources(bus, &add_list, NULL);
521 }
522
523 acpiphp_sanitize_bus(bus);
524 pcie_bus_configure_settings(bus);
525 acpiphp_set_acpi_region(slot);
526
527 list_for_each_entry(dev, &bus->devices, bus_list) {
528 /* Assume that newly added devices are powered on already. */
529 if (!pci_dev_is_added(dev))
530 dev->current_state = PCI_D0;
531 }
532
533 pci_bus_add_devices(bus);
534
535 slot->flags |= SLOT_ENABLED;
536 list_for_each_entry(func, &slot->funcs, sibling) {
537 dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
538 func->function));
539 if (!dev) {
540 /* Do not set SLOT_ENABLED flag if some funcs
541 are not added. */
542 slot->flags &= ~SLOT_ENABLED;
543 continue;
544 }
545 pci_dev_put(dev);
546 }
547}
548
549/**
550 * disable_slot - disable a slot
551 * @slot: ACPI PHP slot
552 */
553static void disable_slot(struct acpiphp_slot *slot)
554{
555 struct pci_bus *bus = slot->bus;
556 struct pci_dev *dev, *prev;
557 struct acpiphp_func *func;
558
559 /*
560 * enable_slot() enumerates all functions in this device via
561 * pci_scan_slot(), whether they have associated ACPI hotplug
562 * methods (_EJ0, etc.) or not. Therefore, we remove all functions
563 * here.
564 */
565 list_for_each_entry_safe_reverse(dev, prev, &bus->devices, bus_list)
566 if (PCI_SLOT(dev->devfn) == slot->device)
567 pci_stop_and_remove_bus_device(dev);
568
569 list_for_each_entry(func, &slot->funcs, sibling)
570 acpi_bus_trim(func_to_acpi_device(func));
571
572 slot->flags &= ~SLOT_ENABLED;
573}
574
575static bool slot_no_hotplug(struct acpiphp_slot *slot)
576{
577 struct pci_bus *bus = slot->bus;
578 struct pci_dev *dev;
579
580 list_for_each_entry(dev, &bus->devices, bus_list) {
581 if (PCI_SLOT(dev->devfn) == slot->device && dev->ignore_hotplug)
582 return true;
583 }
584 return false;
585}
586
587/**
588 * get_slot_status - get ACPI slot status
589 * @slot: ACPI PHP slot
590 *
591 * If a slot has _STA for each function and if any one of them
592 * returned non-zero status, return it.
593 *
594 * If a slot doesn't have _STA and if any one of its functions'
595 * configuration space is configured, return 0x0f as a _STA.
596 *
597 * Otherwise return 0.
598 */
599static unsigned int get_slot_status(struct acpiphp_slot *slot)
600{
601 unsigned long long sta = 0;
602 struct acpiphp_func *func;
603 u32 dvid;
604
605 list_for_each_entry(func, &slot->funcs, sibling) {
606 if (func->flags & FUNC_HAS_STA) {
607 acpi_status status;
608
609 status = acpi_evaluate_integer(func_to_handle(func),
610 "_STA", NULL, &sta);
611 if (ACPI_SUCCESS(status) && sta)
612 break;
613 } else {
614 if (pci_bus_read_dev_vendor_id(slot->bus,
615 PCI_DEVFN(slot->device, func->function),
616 &dvid, 0)) {
617 sta = ACPI_STA_ALL;
618 break;
619 }
620 }
621 }
622
623 if (!sta) {
624 /*
625 * Check for the slot itself since it may be that the
626 * ACPI slot is a device below PCIe upstream port so in
627 * that case it may not even be reachable yet.
628 */
629 if (pci_bus_read_dev_vendor_id(slot->bus,
630 PCI_DEVFN(slot->device, 0), &dvid, 0)) {
631 sta = ACPI_STA_ALL;
632 }
633 }
634
635 return (unsigned int)sta;
636}
637
638static inline bool device_status_valid(unsigned int sta)
639{
640 /*
641 * ACPI spec says that _STA may return bit 0 clear with bit 3 set
642 * if the device is valid but does not require a device driver to be
643 * loaded (Section 6.3.7 of ACPI 5.0A).
644 */
645 unsigned int mask = ACPI_STA_DEVICE_ENABLED | ACPI_STA_DEVICE_FUNCTIONING;
646 return (sta & mask) == mask;
647}
648
649/**
650 * trim_stale_devices - remove PCI devices that are not responding.
651 * @dev: PCI device to start walking the hierarchy from.
652 */
653static void trim_stale_devices(struct pci_dev *dev)
654{
655 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
656 struct pci_bus *bus = dev->subordinate;
657 bool alive = dev->ignore_hotplug;
658
659 if (adev) {
660 acpi_status status;
661 unsigned long long sta;
662
663 status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
664 alive = alive || (ACPI_SUCCESS(status) && device_status_valid(sta));
665 }
666 if (!alive)
667 alive = pci_device_is_present(dev);
668
669 if (!alive) {
670 pci_dev_set_disconnected(dev, NULL);
671 if (pci_has_subordinate(dev))
672 pci_walk_bus(dev->subordinate, pci_dev_set_disconnected,
673 NULL);
674
675 pci_stop_and_remove_bus_device(dev);
676 if (adev)
677 acpi_bus_trim(adev);
678 } else if (bus) {
679 struct pci_dev *child, *tmp;
680
681 /* The device is a bridge. so check the bus below it. */
682 pm_runtime_get_sync(&dev->dev);
683 list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
684 trim_stale_devices(child);
685
686 pm_runtime_put(&dev->dev);
687 }
688}
689
690/**
691 * acpiphp_check_bridge - re-enumerate devices
692 * @bridge: where to begin re-enumeration
693 *
694 * Iterate over all slots under this bridge and make sure that if a
695 * card is present they are enabled, and if not they are disabled.
696 */
697static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
698{
699 struct acpiphp_slot *slot;
700
701 /* Bail out if the bridge is going away. */
702 if (bridge->is_going_away)
703 return;
704
705 if (bridge->pci_dev)
706 pm_runtime_get_sync(&bridge->pci_dev->dev);
707
708 list_for_each_entry(slot, &bridge->slots, node) {
709 struct pci_bus *bus = slot->bus;
710 struct pci_dev *dev, *tmp;
711
712 if (slot_no_hotplug(slot)) {
713 ; /* do nothing */
714 } else if (device_status_valid(get_slot_status(slot))) {
715 /* remove stale devices if any */
716 list_for_each_entry_safe_reverse(dev, tmp,
717 &bus->devices, bus_list)
718 if (PCI_SLOT(dev->devfn) == slot->device)
719 trim_stale_devices(dev);
720
721 /* configure all functions */
722 enable_slot(slot, true);
723 } else {
724 disable_slot(slot);
725 }
726 }
727
728 if (bridge->pci_dev)
729 pm_runtime_put(&bridge->pci_dev->dev);
730}
731
732/*
733 * Remove devices for which we could not assign resources, call
734 * arch specific code to fix-up the bus
735 */
736static void acpiphp_sanitize_bus(struct pci_bus *bus)
737{
738 struct pci_dev *dev, *tmp;
739 int i;
740 unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
741
742 list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
743 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
744 struct resource *res = &dev->resource[i];
745 if ((res->flags & type_mask) && !res->start &&
746 res->end) {
747 /* Could not assign a required resources
748 * for this device, remove it */
749 pci_stop_and_remove_bus_device(dev);
750 break;
751 }
752 }
753 }
754}
755
756/*
757 * ACPI event handlers
758 */
759
760void acpiphp_check_host_bridge(struct acpi_device *adev)
761{
762 struct acpiphp_bridge *bridge = NULL;
763
764 acpi_lock_hp_context();
765 if (adev->hp) {
766 bridge = to_acpiphp_root_context(adev->hp)->root_bridge;
767 if (bridge)
768 get_bridge(bridge);
769 }
770 acpi_unlock_hp_context();
771 if (bridge) {
772 pci_lock_rescan_remove();
773
774 acpiphp_check_bridge(bridge);
775
776 pci_unlock_rescan_remove();
777 put_bridge(bridge);
778 }
779}
780
781static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
782
783static void hotplug_event(u32 type, struct acpiphp_context *context)
784{
785 acpi_handle handle = context->hp.self->handle;
786 struct acpiphp_func *func = &context->func;
787 struct acpiphp_slot *slot = func->slot;
788 struct acpiphp_bridge *bridge;
789
790 acpi_lock_hp_context();
791 bridge = context->bridge;
792 if (bridge)
793 get_bridge(bridge);
794
795 acpi_unlock_hp_context();
796
797 pci_lock_rescan_remove();
798
799 switch (type) {
800 case ACPI_NOTIFY_BUS_CHECK:
801 /* bus re-enumerate */
802 acpi_handle_debug(handle, "Bus check in %s()\n", __func__);
803 if (bridge)
804 acpiphp_check_bridge(bridge);
805 else if (!(slot->flags & SLOT_IS_GOING_AWAY))
806 enable_slot(slot, false);
807
808 break;
809
810 case ACPI_NOTIFY_DEVICE_CHECK:
811 /* device check */
812 acpi_handle_debug(handle, "Device check in %s()\n", __func__);
813 if (bridge) {
814 acpiphp_check_bridge(bridge);
815 } else if (!(slot->flags & SLOT_IS_GOING_AWAY)) {
816 /*
817 * Check if anything has changed in the slot and rescan
818 * from the parent if that's the case.
819 */
820 if (acpiphp_rescan_slot(slot))
821 acpiphp_check_bridge(func->parent);
822 }
823 break;
824
825 case ACPI_NOTIFY_EJECT_REQUEST:
826 /* request device eject */
827 acpi_handle_debug(handle, "Eject request in %s()\n", __func__);
828 acpiphp_disable_and_eject_slot(slot);
829 break;
830 }
831
832 pci_unlock_rescan_remove();
833 if (bridge)
834 put_bridge(bridge);
835}
836
837static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type)
838{
839 struct acpiphp_context *context;
840
841 context = acpiphp_grab_context(adev);
842 if (!context)
843 return -ENODATA;
844
845 hotplug_event(type, context);
846 acpiphp_let_context_go(context);
847 return 0;
848}
849
850/**
851 * acpiphp_enumerate_slots - Enumerate PCI slots for a given bus.
852 * @bus: PCI bus to enumerate the slots for.
853 *
854 * A "slot" is an object associated with a PCI device number. All functions
855 * (PCI devices) with the same bus and device number belong to the same slot.
856 */
857void acpiphp_enumerate_slots(struct pci_bus *bus)
858{
859 struct acpiphp_bridge *bridge;
860 struct acpi_device *adev;
861 acpi_handle handle;
862 acpi_status status;
863
864 if (acpiphp_disabled)
865 return;
866
867 adev = ACPI_COMPANION(bus->bridge);
868 if (!adev)
869 return;
870
871 handle = adev->handle;
872 bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
873 if (!bridge)
874 return;
875
876 INIT_LIST_HEAD(&bridge->slots);
877 kref_init(&bridge->ref);
878 bridge->pci_dev = pci_dev_get(bus->self);
879 bridge->pci_bus = bus;
880
881 /*
882 * Grab a ref to the subordinate PCI bus in case the bus is
883 * removed via PCI core logical hotplug. The ref pins the bus
884 * (which we access during module unload).
885 */
886 get_device(&bus->dev);
887
888 acpi_lock_hp_context();
889 if (pci_is_root_bus(bridge->pci_bus)) {
890 struct acpiphp_root_context *root_context;
891
892 root_context = kzalloc(sizeof(*root_context), GFP_KERNEL);
893 if (!root_context)
894 goto err;
895
896 root_context->root_bridge = bridge;
897 acpi_set_hp_context(adev, &root_context->hp);
898 } else {
899 struct acpiphp_context *context;
900
901 /*
902 * This bridge should have been registered as a hotplug function
903 * under its parent, so the context should be there, unless the
904 * parent is going to be handled by pciehp, in which case this
905 * bridge is not interesting to us either.
906 */
907 context = acpiphp_get_context(adev);
908 if (!context)
909 goto err;
910
911 bridge->context = context;
912 context->bridge = bridge;
913 /* Get a reference to the parent bridge. */
914 get_bridge(context->func.parent);
915 }
916 acpi_unlock_hp_context();
917
918 /* Must be added to the list prior to calling acpiphp_add_context(). */
919 mutex_lock(&bridge_mutex);
920 list_add(&bridge->list, &bridge_list);
921 mutex_unlock(&bridge_mutex);
922
923 /* register all slot objects under this bridge */
924 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
925 acpiphp_add_context, NULL, bridge, NULL);
926 if (ACPI_FAILURE(status)) {
927 acpi_handle_err(handle, "failed to register slots\n");
928 cleanup_bridge(bridge);
929 put_bridge(bridge);
930 }
931 return;
932
933 err:
934 acpi_unlock_hp_context();
935 put_device(&bus->dev);
936 pci_dev_put(bridge->pci_dev);
937 kfree(bridge);
938}
939
940static void acpiphp_drop_bridge(struct acpiphp_bridge *bridge)
941{
942 if (pci_is_root_bus(bridge->pci_bus)) {
943 struct acpiphp_root_context *root_context;
944 struct acpi_device *adev;
945
946 acpi_lock_hp_context();
947 adev = ACPI_COMPANION(bridge->pci_bus->bridge);
948 root_context = to_acpiphp_root_context(adev->hp);
949 adev->hp = NULL;
950 acpi_unlock_hp_context();
951 kfree(root_context);
952 }
953 cleanup_bridge(bridge);
954 put_bridge(bridge);
955}
956
957/**
958 * acpiphp_remove_slots - Remove slot objects associated with a given bus.
959 * @bus: PCI bus to remove the slot objects for.
960 */
961void acpiphp_remove_slots(struct pci_bus *bus)
962{
963 struct acpiphp_bridge *bridge;
964
965 if (acpiphp_disabled)
966 return;
967
968 mutex_lock(&bridge_mutex);
969 list_for_each_entry(bridge, &bridge_list, list)
970 if (bridge->pci_bus == bus) {
971 mutex_unlock(&bridge_mutex);
972 acpiphp_drop_bridge(bridge);
973 return;
974 }
975
976 mutex_unlock(&bridge_mutex);
977}
978
979/**
980 * acpiphp_enable_slot - power on slot
981 * @slot: ACPI PHP slot
982 */
983int acpiphp_enable_slot(struct acpiphp_slot *slot)
984{
985 pci_lock_rescan_remove();
986
987 if (slot->flags & SLOT_IS_GOING_AWAY) {
988 pci_unlock_rescan_remove();
989 return -ENODEV;
990 }
991
992 /* configure all functions */
993 if (!(slot->flags & SLOT_ENABLED))
994 enable_slot(slot, false);
995
996 pci_unlock_rescan_remove();
997 return 0;
998}
999
1000/**
1001 * acpiphp_disable_and_eject_slot - power off and eject slot
1002 * @slot: ACPI PHP slot
1003 */
1004static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
1005{
1006 struct acpiphp_func *func;
1007
1008 if (slot->flags & SLOT_IS_GOING_AWAY)
1009 return -ENODEV;
1010
1011 /* unconfigure all functions */
1012 disable_slot(slot);
1013
1014 list_for_each_entry(func, &slot->funcs, sibling)
1015 if (func->flags & FUNC_HAS_EJ0) {
1016 acpi_handle handle = func_to_handle(func);
1017
1018 if (ACPI_FAILURE(acpi_evaluate_ej0(handle)))
1019 acpi_handle_err(handle, "_EJ0 failed\n");
1020
1021 break;
1022 }
1023
1024 return 0;
1025}
1026
1027int acpiphp_disable_slot(struct acpiphp_slot *slot)
1028{
1029 int ret;
1030
1031 /*
1032 * Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
1033 * acpiphp_disable_and_eject_slot() will be synchronized properly.
1034 */
1035 acpi_scan_lock_acquire();
1036 pci_lock_rescan_remove();
1037 ret = acpiphp_disable_and_eject_slot(slot);
1038 pci_unlock_rescan_remove();
1039 acpi_scan_lock_release();
1040 return ret;
1041}
1042
1043/*
1044 * slot enabled: 1
1045 * slot disabled: 0
1046 */
1047u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
1048{
1049 return (slot->flags & SLOT_ENABLED);
1050}
1051
1052/*
1053 * latch open: 1
1054 * latch closed: 0
1055 */
1056u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
1057{
1058 return !(get_slot_status(slot) & ACPI_STA_DEVICE_UI);
1059}
1060
1061/*
1062 * adapter presence : 1
1063 * absence : 0
1064 */
1065u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
1066{
1067 return !!get_slot_status(slot);
1068}