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