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_func has its refcount elevated by pci_get_slot()
36  *    when the driver is loaded or when an insertion event occurs.  It loses
37  *    a refcount when its ejected or the driver unloads.
38  *  - The one in acpiphp_bridge has its refcount elevated by pci_get_slot()
39  *    when the bridge is scanned and it loses a refcount when the bridge
40  *    is removed.
41  */
42 
43 #include <linux/init.h>
44 #include <linux/module.h>
45 
46 #include <linux/kernel.h>
47 #include <linux/pci.h>
48 #include <linux/smp_lock.h>
49 #include <linux/mutex.h>
50 
51 #include "../pci.h"
52 #include "pci_hotplug.h"
53 #include "acpiphp.h"
54 
55 static LIST_HEAD(bridge_list);
56 
57 #define MY_NAME "acpiphp_glue"
58 
59 static void handle_hotplug_event_bridge (acpi_handle, u32, void *);
60 static void acpiphp_sanitize_bus(struct pci_bus *bus);
61 static void acpiphp_set_hpp_values(acpi_handle handle, struct pci_bus *bus);
62 static void handle_hotplug_event_func(acpi_handle handle, u32 type, void *context);
63 
64 
65 /*
66  * initialization & terminatation routines
67  */
68 
69 /**
70  * is_ejectable - determine if a slot is ejectable
71  * @handle: handle to acpi namespace
72  *
73  * Ejectable slot should satisfy at least these conditions:
74  *
75  *  1. has _ADR method
76  *  2. has _EJ0 method
77  *
78  * optionally
79  *
80  *  1. has _STA method
81  *  2. has _PS0 method
82  *  3. has _PS3 method
83  *  4. ..
84  *
85  */
86 static int is_ejectable(acpi_handle handle)
87 {
88 	acpi_status status;
89 	acpi_handle tmp;
90 
91 	status = acpi_get_handle(handle, "_ADR", &tmp);
92 	if (ACPI_FAILURE(status)) {
93 		return 0;
94 	}
95 
96 	status = acpi_get_handle(handle, "_EJ0", &tmp);
97 	if (ACPI_FAILURE(status)) {
98 		return 0;
99 	}
100 
101 	return 1;
102 }
103 
104 
105 /* callback routine to check the existence of ejectable slots */
106 static acpi_status
107 is_ejectable_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
108 {
109 	int *count = (int *)context;
110 
111 	if (is_ejectable(handle)) {
112 		(*count)++;
113 		/* only one ejectable slot is enough */
114 		return AE_CTRL_TERMINATE;
115 	} else {
116 		return AE_OK;
117 	}
118 }
119 
120 /* callback routine to check for the existance of a pci dock device */
121 static acpi_status
122 is_pci_dock_device(acpi_handle handle, u32 lvl, void *context, void **rv)
123 {
124 	int *count = (int *)context;
125 
126 	if (is_dock_device(handle)) {
127 		(*count)++;
128 		return AE_CTRL_TERMINATE;
129 	} else {
130 		return AE_OK;
131 	}
132 }
133 
134 
135 
136 
137 /*
138  * the _DCK method can do funny things... and sometimes not
139  * hah-hah funny.
140  *
141  * TBD - figure out a way to only call fixups for
142  * systems that require them.
143  */
144 static int post_dock_fixups(struct notifier_block *nb, unsigned long val,
145 	void *v)
146 {
147 	struct acpiphp_func *func = container_of(nb, struct acpiphp_func, nb);
148 	struct pci_bus *bus = func->slot->bridge->pci_bus;
149 	u32 buses;
150 
151 	if (!bus->self)
152 		return  NOTIFY_OK;
153 
154 	/* fixup bad _DCK function that rewrites
155 	 * secondary bridge on slot
156 	 */
157 	pci_read_config_dword(bus->self,
158 			PCI_PRIMARY_BUS,
159 			&buses);
160 
161 	if (((buses >> 8) & 0xff) != bus->secondary) {
162 		buses = (buses & 0xff000000)
163 	     		| ((unsigned int)(bus->primary)     <<  0)
164 	     		| ((unsigned int)(bus->secondary)   <<  8)
165 	     		| ((unsigned int)(bus->subordinate) << 16);
166 		pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
167 	}
168 	return NOTIFY_OK;
169 }
170 
171 
172 
173 
174 /* callback routine to register each ACPI PCI slot object */
175 static acpi_status
176 register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
177 {
178 	struct acpiphp_bridge *bridge = (struct acpiphp_bridge *)context;
179 	struct acpiphp_slot *slot;
180 	struct acpiphp_func *newfunc;
181 	acpi_handle tmp;
182 	acpi_status status = AE_OK;
183 	unsigned long adr, sun;
184 	int device, function, retval;
185 
186 	status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
187 
188 	if (ACPI_FAILURE(status))
189 		return AE_OK;
190 
191 	status = acpi_get_handle(handle, "_EJ0", &tmp);
192 
193 	if (ACPI_FAILURE(status) && !(is_dock_device(handle)))
194 		return AE_OK;
195 
196 	device = (adr >> 16) & 0xffff;
197 	function = adr & 0xffff;
198 
199 	newfunc = kzalloc(sizeof(struct acpiphp_func), GFP_KERNEL);
200 	if (!newfunc)
201 		return AE_NO_MEMORY;
202 
203 	INIT_LIST_HEAD(&newfunc->sibling);
204 	newfunc->handle = handle;
205 	newfunc->function = function;
206 	if (ACPI_SUCCESS(status))
207 		newfunc->flags = FUNC_HAS_EJ0;
208 
209 	if (ACPI_SUCCESS(acpi_get_handle(handle, "_STA", &tmp)))
210 		newfunc->flags |= FUNC_HAS_STA;
211 
212 	if (ACPI_SUCCESS(acpi_get_handle(handle, "_PS0", &tmp)))
213 		newfunc->flags |= FUNC_HAS_PS0;
214 
215 	if (ACPI_SUCCESS(acpi_get_handle(handle, "_PS3", &tmp)))
216 		newfunc->flags |= FUNC_HAS_PS3;
217 
218 	if (ACPI_SUCCESS(acpi_get_handle(handle, "_DCK", &tmp)))
219 		newfunc->flags |= FUNC_HAS_DCK;
220 
221 	status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
222 	if (ACPI_FAILURE(status)) {
223 		/*
224 		 * use the count of the number of slots we've found
225 		 * for the number of the slot
226 		 */
227 		sun = bridge->nr_slots+1;
228 	}
229 
230 	/* search for objects that share the same slot */
231 	for (slot = bridge->slots; slot; slot = slot->next)
232 		if (slot->device == device) {
233 			if (slot->sun != sun)
234 				warn("sibling found, but _SUN doesn't match!\n");
235 			break;
236 		}
237 
238 	if (!slot) {
239 		slot = kzalloc(sizeof(struct acpiphp_slot), GFP_KERNEL);
240 		if (!slot) {
241 			kfree(newfunc);
242 			return AE_NO_MEMORY;
243 		}
244 
245 		slot->bridge = bridge;
246 		slot->device = device;
247 		slot->sun = sun;
248 		INIT_LIST_HEAD(&slot->funcs);
249 		mutex_init(&slot->crit_sect);
250 
251 		slot->next = bridge->slots;
252 		bridge->slots = slot;
253 
254 		bridge->nr_slots++;
255 
256 		dbg("found ACPI PCI Hotplug slot %d at PCI %04x:%02x:%02x\n",
257 				slot->sun, pci_domain_nr(bridge->pci_bus),
258 				bridge->pci_bus->number, slot->device);
259 		retval = acpiphp_register_hotplug_slot(slot);
260 		if (retval) {
261 			warn("acpiphp_register_hotplug_slot failed(err code = 0x%x)\n", retval);
262 			goto err_exit;
263 		}
264 	}
265 
266 	newfunc->slot = slot;
267 	list_add_tail(&newfunc->sibling, &slot->funcs);
268 
269 	/* associate corresponding pci_dev */
270 	newfunc->pci_dev = pci_get_slot(bridge->pci_bus,
271 					 PCI_DEVFN(device, function));
272 	if (newfunc->pci_dev) {
273 		slot->flags |= (SLOT_ENABLED | SLOT_POWEREDON);
274 	}
275 
276 	if (is_dock_device(handle)) {
277 		/* we don't want to call this device's _EJ0
278 		 * because we want the dock notify handler
279 		 * to call it after it calls _DCK
280 		 */
281 		newfunc->flags &= ~FUNC_HAS_EJ0;
282 		if (register_hotplug_dock_device(handle,
283 			handle_hotplug_event_func, newfunc))
284 			dbg("failed to register dock device\n");
285 
286 		/* we need to be notified when dock events happen
287 		 * outside of the hotplug operation, since we may
288 		 * need to do fixups before we can hotplug.
289 		 */
290 		newfunc->nb.notifier_call = post_dock_fixups;
291 		if (register_dock_notifier(&newfunc->nb))
292 			dbg("failed to register a dock notifier");
293 	}
294 
295 	/* install notify handler */
296 	if (!(newfunc->flags & FUNC_HAS_DCK)) {
297 		status = acpi_install_notify_handler(handle,
298 					     ACPI_SYSTEM_NOTIFY,
299 					     handle_hotplug_event_func,
300 					     newfunc);
301 
302 		if (ACPI_FAILURE(status))
303 			err("failed to register interrupt notify handler\n");
304 	} else
305 		status = AE_OK;
306 
307 	return status;
308 
309  err_exit:
310 	bridge->nr_slots--;
311 	bridge->slots = slot->next;
312 	kfree(slot);
313 	kfree(newfunc);
314 
315 	return AE_OK;
316 }
317 
318 
319 /* see if it's worth looking at this bridge */
320 static int detect_ejectable_slots(acpi_handle *bridge_handle)
321 {
322 	acpi_status status;
323 	int count;
324 
325 	count = 0;
326 
327 	/* only check slots defined directly below bridge object */
328 	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, bridge_handle, (u32)1,
329 				     is_ejectable_slot, (void *)&count, NULL);
330 
331 	/*
332 	 * we also need to add this bridge if there is a dock bridge or
333 	 * other pci device on a dock station (removable)
334 	 */
335 	if (!count)
336 		status = acpi_walk_namespace(ACPI_TYPE_DEVICE, bridge_handle,
337 				(u32)1, is_pci_dock_device, (void *)&count,
338 				NULL);
339 
340 	return count;
341 }
342 
343 
344 /* decode ACPI 2.0 _HPP hot plug parameters */
345 static void decode_hpp(struct acpiphp_bridge *bridge)
346 {
347 	acpi_status status;
348 
349 	status = acpi_get_hp_params_from_firmware(bridge->pci_bus, &bridge->hpp);
350 	if (ACPI_FAILURE(status) ||
351 	    !bridge->hpp.t0 || (bridge->hpp.t0->revision > 1)) {
352 		/* use default numbers */
353 		printk(KERN_WARNING
354 		       "%s: Could not get hotplug parameters. Use defaults\n",
355 		       __FUNCTION__);
356 		bridge->hpp.t0 = &bridge->hpp.type0_data;
357 		bridge->hpp.t0->revision = 0;
358 		bridge->hpp.t0->cache_line_size = 0x10;
359 		bridge->hpp.t0->latency_timer = 0x40;
360 		bridge->hpp.t0->enable_serr = 0;
361 		bridge->hpp.t0->enable_perr = 0;
362 	}
363 }
364 
365 
366 
367 /* initialize miscellaneous stuff for both root and PCI-to-PCI bridge */
368 static void init_bridge_misc(struct acpiphp_bridge *bridge)
369 {
370 	acpi_status status;
371 
372 	/* decode ACPI 2.0 _HPP (hot plug parameters) */
373 	decode_hpp(bridge);
374 
375 	/* must be added to the list prior to calling register_slot */
376 	list_add(&bridge->list, &bridge_list);
377 
378 	/* register all slot objects under this bridge */
379 	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, bridge->handle, (u32)1,
380 				     register_slot, bridge, NULL);
381 	if (ACPI_FAILURE(status)) {
382 		list_del(&bridge->list);
383 		return;
384 	}
385 
386 	/* install notify handler */
387 	if (bridge->type != BRIDGE_TYPE_HOST) {
388 		if ((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func) {
389 			status = acpi_remove_notify_handler(bridge->func->handle,
390 						ACPI_SYSTEM_NOTIFY,
391 						handle_hotplug_event_func);
392 			if (ACPI_FAILURE(status))
393 				err("failed to remove notify handler\n");
394 		}
395 		status = acpi_install_notify_handler(bridge->handle,
396 					     ACPI_SYSTEM_NOTIFY,
397 					     handle_hotplug_event_bridge,
398 					     bridge);
399 
400 		if (ACPI_FAILURE(status)) {
401 			err("failed to register interrupt notify handler\n");
402 		}
403 	}
404 }
405 
406 
407 /* find acpiphp_func from acpiphp_bridge */
408 static struct acpiphp_func *acpiphp_bridge_handle_to_function(acpi_handle handle)
409 {
410 	struct list_head *node, *l;
411 	struct acpiphp_bridge *bridge;
412 	struct acpiphp_slot *slot;
413 	struct acpiphp_func *func;
414 
415 	list_for_each(node, &bridge_list) {
416 		bridge = list_entry(node, struct acpiphp_bridge, list);
417 		for (slot = bridge->slots; slot; slot = slot->next) {
418 			list_for_each(l, &slot->funcs) {
419 				func = list_entry(l, struct acpiphp_func,
420 							sibling);
421 				if (func->handle == handle)
422 					return func;
423 			}
424 		}
425 	}
426 
427 	return NULL;
428 }
429 
430 
431 static inline void config_p2p_bridge_flags(struct acpiphp_bridge *bridge)
432 {
433 	acpi_handle dummy_handle;
434 
435 	if (ACPI_SUCCESS(acpi_get_handle(bridge->handle,
436 					"_STA", &dummy_handle)))
437 		bridge->flags |= BRIDGE_HAS_STA;
438 
439 	if (ACPI_SUCCESS(acpi_get_handle(bridge->handle,
440 					"_EJ0", &dummy_handle)))
441 		bridge->flags |= BRIDGE_HAS_EJ0;
442 
443 	if (ACPI_SUCCESS(acpi_get_handle(bridge->handle,
444 					"_PS0", &dummy_handle)))
445 		bridge->flags |= BRIDGE_HAS_PS0;
446 
447 	if (ACPI_SUCCESS(acpi_get_handle(bridge->handle,
448 					"_PS3", &dummy_handle)))
449 		bridge->flags |= BRIDGE_HAS_PS3;
450 
451 	/* is this ejectable p2p bridge? */
452 	if (bridge->flags & BRIDGE_HAS_EJ0) {
453 		struct acpiphp_func *func;
454 
455 		dbg("found ejectable p2p bridge\n");
456 
457 		/* make link between PCI bridge and PCI function */
458 		func = acpiphp_bridge_handle_to_function(bridge->handle);
459 		if (!func)
460 			return;
461 		bridge->func = func;
462 		func->bridge = bridge;
463 	}
464 }
465 
466 
467 /* allocate and initialize host bridge data structure */
468 static void add_host_bridge(acpi_handle *handle, struct pci_bus *pci_bus)
469 {
470 	struct acpiphp_bridge *bridge;
471 
472 	bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
473 	if (bridge == NULL)
474 		return;
475 
476 	bridge->type = BRIDGE_TYPE_HOST;
477 	bridge->handle = handle;
478 
479 	bridge->pci_bus = pci_bus;
480 
481 	spin_lock_init(&bridge->res_lock);
482 
483 	init_bridge_misc(bridge);
484 }
485 
486 
487 /* allocate and initialize PCI-to-PCI bridge data structure */
488 static void add_p2p_bridge(acpi_handle *handle, struct pci_dev *pci_dev)
489 {
490 	struct acpiphp_bridge *bridge;
491 
492 	bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
493 	if (bridge == NULL) {
494 		err("out of memory\n");
495 		return;
496 	}
497 
498 	bridge->type = BRIDGE_TYPE_P2P;
499 	bridge->handle = handle;
500 	config_p2p_bridge_flags(bridge);
501 
502 	bridge->pci_dev = pci_dev_get(pci_dev);
503 	bridge->pci_bus = pci_dev->subordinate;
504 	if (!bridge->pci_bus) {
505 		err("This is not a PCI-to-PCI bridge!\n");
506 		goto err;
507 	}
508 
509 	spin_lock_init(&bridge->res_lock);
510 
511 	init_bridge_misc(bridge);
512 	return;
513  err:
514 	pci_dev_put(pci_dev);
515 	kfree(bridge);
516 	return;
517 }
518 
519 
520 /* callback routine to find P2P bridges */
521 static acpi_status
522 find_p2p_bridge(acpi_handle handle, u32 lvl, void *context, void **rv)
523 {
524 	acpi_status status;
525 	acpi_handle dummy_handle;
526 	unsigned long tmp;
527 	int device, function;
528 	struct pci_dev *dev;
529 	struct pci_bus *pci_bus = context;
530 
531 	status = acpi_get_handle(handle, "_ADR", &dummy_handle);
532 	if (ACPI_FAILURE(status))
533 		return AE_OK;		/* continue */
534 
535 	status = acpi_evaluate_integer(handle, "_ADR", NULL, &tmp);
536 	if (ACPI_FAILURE(status)) {
537 		dbg("%s: _ADR evaluation failure\n", __FUNCTION__);
538 		return AE_OK;
539 	}
540 
541 	device = (tmp >> 16) & 0xffff;
542 	function = tmp & 0xffff;
543 
544 	dev = pci_get_slot(pci_bus, PCI_DEVFN(device, function));
545 
546 	if (!dev || !dev->subordinate)
547 		goto out;
548 
549 	/* check if this bridge has ejectable slots */
550 	if ((detect_ejectable_slots(handle) > 0)) {
551 		dbg("found PCI-to-PCI bridge at PCI %s\n", pci_name(dev));
552 		add_p2p_bridge(handle, dev);
553 	}
554 
555 	/* search P2P bridges under this p2p bridge */
556 	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
557 				     find_p2p_bridge, dev->subordinate, NULL);
558 	if (ACPI_FAILURE(status))
559 		warn("find_p2p_bridge failed (error code = 0x%x)\n", status);
560 
561  out:
562 	pci_dev_put(dev);
563 	return AE_OK;
564 }
565 
566 
567 /* find hot-pluggable slots, and then find P2P bridge */
568 static int add_bridge(acpi_handle handle)
569 {
570 	acpi_status status;
571 	unsigned long tmp;
572 	int seg, bus;
573 	acpi_handle dummy_handle;
574 	struct pci_bus *pci_bus;
575 
576 	/* if the bridge doesn't have _STA, we assume it is always there */
577 	status = acpi_get_handle(handle, "_STA", &dummy_handle);
578 	if (ACPI_SUCCESS(status)) {
579 		status = acpi_evaluate_integer(handle, "_STA", NULL, &tmp);
580 		if (ACPI_FAILURE(status)) {
581 			dbg("%s: _STA evaluation failure\n", __FUNCTION__);
582 			return 0;
583 		}
584 		if ((tmp & ACPI_STA_FUNCTIONING) == 0)
585 			/* don't register this object */
586 			return 0;
587 	}
588 
589 	/* get PCI segment number */
590 	status = acpi_evaluate_integer(handle, "_SEG", NULL, &tmp);
591 
592 	seg = ACPI_SUCCESS(status) ? tmp : 0;
593 
594 	/* get PCI bus number */
595 	status = acpi_evaluate_integer(handle, "_BBN", NULL, &tmp);
596 
597 	if (ACPI_SUCCESS(status)) {
598 		bus = tmp;
599 	} else {
600 		warn("can't get bus number, assuming 0\n");
601 		bus = 0;
602 	}
603 
604 	pci_bus = pci_find_bus(seg, bus);
605 	if (!pci_bus) {
606 		err("Can't find bus %04x:%02x\n", seg, bus);
607 		return 0;
608 	}
609 
610 	/* check if this bridge has ejectable slots */
611 	if (detect_ejectable_slots(handle) > 0) {
612 		dbg("found PCI host-bus bridge with hot-pluggable slots\n");
613 		add_host_bridge(handle, pci_bus);
614 	}
615 
616 	/* search P2P bridges under this host bridge */
617 	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
618 				     find_p2p_bridge, pci_bus, NULL);
619 
620 	if (ACPI_FAILURE(status))
621 		warn("find_p2p_bridge failed (error code = 0x%x)\n", status);
622 
623 	return 0;
624 }
625 
626 static struct acpiphp_bridge *acpiphp_handle_to_bridge(acpi_handle handle)
627 {
628 	struct list_head *head;
629 	list_for_each(head, &bridge_list) {
630 		struct acpiphp_bridge *bridge = list_entry(head,
631 						struct acpiphp_bridge, list);
632 		if (bridge->handle == handle)
633 			return bridge;
634 	}
635 
636 	return NULL;
637 }
638 
639 static void cleanup_bridge(struct acpiphp_bridge *bridge)
640 {
641 	struct list_head *list, *tmp;
642 	struct acpiphp_slot *slot;
643 	acpi_status status;
644 	acpi_handle handle = bridge->handle;
645 
646 	status = acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
647 					    handle_hotplug_event_bridge);
648 	if (ACPI_FAILURE(status))
649 		err("failed to remove notify handler\n");
650 
651 	if ((bridge->type != BRIDGE_TYPE_HOST) &&
652 	    ((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func)) {
653 		status = acpi_install_notify_handler(bridge->func->handle,
654 						ACPI_SYSTEM_NOTIFY,
655 						handle_hotplug_event_func,
656 						bridge->func);
657 		if (ACPI_FAILURE(status))
658 			err("failed to install interrupt notify handler\n");
659 	}
660 
661 	slot = bridge->slots;
662 	while (slot) {
663 		struct acpiphp_slot *next = slot->next;
664 		list_for_each_safe (list, tmp, &slot->funcs) {
665 			struct acpiphp_func *func;
666 			func = list_entry(list, struct acpiphp_func, sibling);
667 			if (is_dock_device(func->handle)) {
668 				unregister_hotplug_dock_device(func->handle);
669 				unregister_dock_notifier(&func->nb);
670 			}
671 			if (!(func->flags & FUNC_HAS_DCK)) {
672 				status = acpi_remove_notify_handler(func->handle,
673 						ACPI_SYSTEM_NOTIFY,
674 						handle_hotplug_event_func);
675 				if (ACPI_FAILURE(status))
676 					err("failed to remove notify handler\n");
677 			}
678 			pci_dev_put(func->pci_dev);
679 			list_del(list);
680 			kfree(func);
681 		}
682 		acpiphp_unregister_hotplug_slot(slot);
683 		list_del(&slot->funcs);
684 		kfree(slot);
685 		slot = next;
686 	}
687 
688 	pci_dev_put(bridge->pci_dev);
689 	list_del(&bridge->list);
690 	kfree(bridge);
691 }
692 
693 static acpi_status
694 cleanup_p2p_bridge(acpi_handle handle, u32 lvl, void *context, void **rv)
695 {
696 	struct acpiphp_bridge *bridge;
697 
698 	/* cleanup p2p bridges under this P2P bridge
699 	   in a depth-first manner */
700 	acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
701 				cleanup_p2p_bridge, NULL, NULL);
702 
703 	if (!(bridge = acpiphp_handle_to_bridge(handle)))
704 		return AE_OK;
705 	cleanup_bridge(bridge);
706 	return AE_OK;
707 }
708 
709 static void remove_bridge(acpi_handle handle)
710 {
711 	struct acpiphp_bridge *bridge;
712 
713 	/* cleanup p2p bridges under this host bridge
714 	   in a depth-first manner */
715 	acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
716 				(u32)1, cleanup_p2p_bridge, NULL, NULL);
717 
718 	bridge = acpiphp_handle_to_bridge(handle);
719 	if (bridge)
720 		cleanup_bridge(bridge);
721 }
722 
723 static struct pci_dev * get_apic_pci_info(acpi_handle handle)
724 {
725 	struct acpi_pci_id id;
726 	struct pci_bus *bus;
727 	struct pci_dev *dev;
728 
729 	if (ACPI_FAILURE(acpi_get_pci_id(handle, &id)))
730 		return NULL;
731 
732 	bus = pci_find_bus(id.segment, id.bus);
733 	if (!bus)
734 		return NULL;
735 
736 	dev = pci_get_slot(bus, PCI_DEVFN(id.device, id.function));
737 	if (!dev)
738 		return NULL;
739 
740 	if ((dev->class != PCI_CLASS_SYSTEM_PIC_IOAPIC) &&
741 	    (dev->class != PCI_CLASS_SYSTEM_PIC_IOXAPIC))
742 	{
743 		pci_dev_put(dev);
744 		return NULL;
745 	}
746 
747 	return dev;
748 }
749 
750 static int get_gsi_base(acpi_handle handle, u32 *gsi_base)
751 {
752 	acpi_status status;
753 	int result = -1;
754 	unsigned long gsb;
755 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
756 	union acpi_object *obj;
757 	void *table;
758 
759 	status = acpi_evaluate_integer(handle, "_GSB", NULL, &gsb);
760 	if (ACPI_SUCCESS(status)) {
761 		*gsi_base = (u32)gsb;
762 		return 0;
763 	}
764 
765 	status = acpi_evaluate_object(handle, "_MAT", NULL, &buffer);
766 	if (ACPI_FAILURE(status) || !buffer.length || !buffer.pointer)
767 		return -1;
768 
769 	obj = buffer.pointer;
770 	if (obj->type != ACPI_TYPE_BUFFER)
771 		goto out;
772 
773 	table = obj->buffer.pointer;
774 	switch (((acpi_table_entry_header *)table)->type) {
775 	case ACPI_MADT_IOSAPIC:
776 		*gsi_base = ((struct acpi_table_iosapic *)table)->global_irq_base;
777 		result = 0;
778 		break;
779 	case ACPI_MADT_IOAPIC:
780 		*gsi_base = ((struct acpi_table_ioapic *)table)->global_irq_base;
781 		result = 0;
782 		break;
783 	default:
784 		break;
785 	}
786  out:
787 	kfree(buffer.pointer);
788 	return result;
789 }
790 
791 static acpi_status
792 ioapic_add(acpi_handle handle, u32 lvl, void *context, void **rv)
793 {
794 	acpi_status status;
795 	unsigned long sta;
796 	acpi_handle tmp;
797 	struct pci_dev *pdev;
798 	u32 gsi_base;
799 	u64 phys_addr;
800 
801 	/* Evaluate _STA if present */
802 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
803 	if (ACPI_SUCCESS(status) && sta != ACPI_STA_ALL)
804 		return AE_CTRL_DEPTH;
805 
806 	/* Scan only PCI bus scope */
807 	status = acpi_get_handle(handle, "_HID", &tmp);
808 	if (ACPI_SUCCESS(status))
809 		return AE_CTRL_DEPTH;
810 
811 	if (get_gsi_base(handle, &gsi_base))
812 		return AE_OK;
813 
814 	pdev = get_apic_pci_info(handle);
815 	if (!pdev)
816 		return AE_OK;
817 
818 	if (pci_enable_device(pdev)) {
819 		pci_dev_put(pdev);
820 		return AE_OK;
821 	}
822 
823 	pci_set_master(pdev);
824 
825 	if (pci_request_region(pdev, 0, "I/O APIC(acpiphp)")) {
826 		pci_disable_device(pdev);
827 		pci_dev_put(pdev);
828 		return AE_OK;
829 	}
830 
831 	phys_addr = pci_resource_start(pdev, 0);
832 	if (acpi_register_ioapic(handle, phys_addr, gsi_base)) {
833 		pci_release_region(pdev, 0);
834 		pci_disable_device(pdev);
835 		pci_dev_put(pdev);
836 		return AE_OK;
837 	}
838 
839 	return AE_OK;
840 }
841 
842 static int acpiphp_configure_ioapics(acpi_handle handle)
843 {
844 	ioapic_add(handle, 0, NULL, NULL);
845 	acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
846 			    ACPI_UINT32_MAX, ioapic_add, NULL, NULL);
847 	return 0;
848 }
849 
850 static int power_on_slot(struct acpiphp_slot *slot)
851 {
852 	acpi_status status;
853 	struct acpiphp_func *func;
854 	struct list_head *l;
855 	int retval = 0;
856 
857 	/* if already enabled, just skip */
858 	if (slot->flags & SLOT_POWEREDON)
859 		goto err_exit;
860 
861 	list_for_each (l, &slot->funcs) {
862 		func = list_entry(l, struct acpiphp_func, sibling);
863 
864 		if (func->flags & FUNC_HAS_PS0) {
865 			dbg("%s: executing _PS0\n", __FUNCTION__);
866 			status = acpi_evaluate_object(func->handle, "_PS0", NULL, NULL);
867 			if (ACPI_FAILURE(status)) {
868 				warn("%s: _PS0 failed\n", __FUNCTION__);
869 				retval = -1;
870 				goto err_exit;
871 			} else
872 				break;
873 		}
874 	}
875 
876 	/* TBD: evaluate _STA to check if the slot is enabled */
877 
878 	slot->flags |= SLOT_POWEREDON;
879 
880  err_exit:
881 	return retval;
882 }
883 
884 
885 static int power_off_slot(struct acpiphp_slot *slot)
886 {
887 	acpi_status status;
888 	struct acpiphp_func *func;
889 	struct list_head *l;
890 
891 	int retval = 0;
892 
893 	/* if already disabled, just skip */
894 	if ((slot->flags & SLOT_POWEREDON) == 0)
895 		goto err_exit;
896 
897 	list_for_each (l, &slot->funcs) {
898 		func = list_entry(l, struct acpiphp_func, sibling);
899 
900 		if (func->flags & FUNC_HAS_PS3) {
901 			status = acpi_evaluate_object(func->handle, "_PS3", NULL, NULL);
902 			if (ACPI_FAILURE(status)) {
903 				warn("%s: _PS3 failed\n", __FUNCTION__);
904 				retval = -1;
905 				goto err_exit;
906 			} else
907 				break;
908 		}
909 	}
910 
911 	/* TBD: evaluate _STA to check if the slot is disabled */
912 
913 	slot->flags &= (~SLOT_POWEREDON);
914 
915  err_exit:
916 	return retval;
917 }
918 
919 
920 
921 /**
922  * acpiphp_max_busnr - return the highest reserved bus number under
923  * the given bus.
924  * @bus: bus to start search with
925  *
926  */
927 static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
928 {
929 	struct list_head *tmp;
930 	unsigned char max, n;
931 
932 	/*
933 	 * pci_bus_max_busnr will return the highest
934 	 * reserved busnr for all these children.
935 	 * that is equivalent to the bus->subordinate
936 	 * value.  We don't want to use the parent's
937 	 * bus->subordinate value because it could have
938 	 * padding in it.
939 	 */
940 	max = bus->secondary;
941 
942 	list_for_each(tmp, &bus->children) {
943 		n = pci_bus_max_busnr(pci_bus_b(tmp));
944 		if (n > max)
945 			max = n;
946 	}
947 	return max;
948 }
949 
950 
951 /**
952  * acpiphp_bus_add - add a new bus to acpi subsystem
953  * @func: acpiphp_func of the bridge
954  *
955  */
956 static int acpiphp_bus_add(struct acpiphp_func *func)
957 {
958 	acpi_handle phandle;
959 	struct acpi_device *device, *pdevice;
960 	int ret_val;
961 
962 	acpi_get_parent(func->handle, &phandle);
963 	if (acpi_bus_get_device(phandle, &pdevice)) {
964 		dbg("no parent device, assuming NULL\n");
965 		pdevice = NULL;
966 	}
967 	if (!acpi_bus_get_device(func->handle, &device)) {
968 		dbg("bus exists... trim\n");
969 		/* this shouldn't be in here, so remove
970 		 * the bus then re-add it...
971 		 */
972 		ret_val = acpi_bus_trim(device, 1);
973 		dbg("acpi_bus_trim return %x\n", ret_val);
974 	}
975 
976 	ret_val = acpi_bus_add(&device, pdevice, func->handle,
977 		ACPI_BUS_TYPE_DEVICE);
978 	if (ret_val) {
979 		dbg("error adding bus, %x\n",
980 			-ret_val);
981 		goto acpiphp_bus_add_out;
982 	}
983 	/*
984 	 * try to start anyway.  We could have failed to add
985 	 * simply because this bus had previously been added
986 	 * on another add.  Don't bother with the return value
987 	 * we just keep going.
988 	 */
989 	ret_val = acpi_bus_start(device);
990 
991 acpiphp_bus_add_out:
992 	return ret_val;
993 }
994 
995 
996 /**
997  * acpiphp_bus_trim - trim a bus from acpi subsystem
998  * @handle: handle to acpi namespace
999  *
1000  */
1001 static int acpiphp_bus_trim(acpi_handle handle)
1002 {
1003 	struct acpi_device *device;
1004 	int retval;
1005 
1006 	retval = acpi_bus_get_device(handle, &device);
1007 	if (retval) {
1008 		dbg("acpi_device not found\n");
1009 		return retval;
1010 	}
1011 
1012 	retval = acpi_bus_trim(device, 1);
1013 	if (retval)
1014 		err("cannot remove from acpi list\n");
1015 
1016 	return retval;
1017 }
1018 
1019 /**
1020  * enable_device - enable, configure a slot
1021  * @slot: slot to be enabled
1022  *
1023  * This function should be called per *physical slot*,
1024  * not per each slot object in ACPI namespace.
1025  *
1026  */
1027 static int enable_device(struct acpiphp_slot *slot)
1028 {
1029 	struct pci_dev *dev;
1030 	struct pci_bus *bus = slot->bridge->pci_bus;
1031 	struct list_head *l;
1032 	struct acpiphp_func *func;
1033 	int retval = 0;
1034 	int num, max, pass;
1035 	acpi_status status;
1036 
1037 	if (slot->flags & SLOT_ENABLED)
1038 		goto err_exit;
1039 
1040 	/* sanity check: dev should be NULL when hot-plugged in */
1041 	dev = pci_get_slot(bus, PCI_DEVFN(slot->device, 0));
1042 	if (dev) {
1043 		/* This case shouldn't happen */
1044 		err("pci_dev structure already exists.\n");
1045 		pci_dev_put(dev);
1046 		retval = -1;
1047 		goto err_exit;
1048 	}
1049 
1050 	num = pci_scan_slot(bus, PCI_DEVFN(slot->device, 0));
1051 	if (num == 0) {
1052 		err("No new device found\n");
1053 		retval = -1;
1054 		goto err_exit;
1055 	}
1056 
1057 	max = acpiphp_max_busnr(bus);
1058 	for (pass = 0; pass < 2; pass++) {
1059 		list_for_each_entry(dev, &bus->devices, bus_list) {
1060 			if (PCI_SLOT(dev->devfn) != slot->device)
1061 				continue;
1062 			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1063 			    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
1064 				max = pci_scan_bridge(bus, dev, max, pass);
1065 				if (pass && dev->subordinate)
1066 					pci_bus_size_bridges(dev->subordinate);
1067 			}
1068 		}
1069 	}
1070 
1071 	list_for_each (l, &slot->funcs) {
1072 		func = list_entry(l, struct acpiphp_func, sibling);
1073 		acpiphp_bus_add(func);
1074 	}
1075 
1076 	pci_bus_assign_resources(bus);
1077 	acpiphp_sanitize_bus(bus);
1078 	acpiphp_set_hpp_values(slot->bridge->handle, bus);
1079 	list_for_each_entry(func, &slot->funcs, sibling)
1080 		acpiphp_configure_ioapics(func->handle);
1081 	pci_enable_bridges(bus);
1082 	pci_bus_add_devices(bus);
1083 
1084 	/* associate pci_dev to our representation */
1085 	list_for_each (l, &slot->funcs) {
1086 		func = list_entry(l, struct acpiphp_func, sibling);
1087 		func->pci_dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
1088 							func->function));
1089 		if (!func->pci_dev)
1090 			continue;
1091 
1092 		if (func->pci_dev->hdr_type != PCI_HEADER_TYPE_BRIDGE &&
1093 		    func->pci_dev->hdr_type != PCI_HEADER_TYPE_CARDBUS)
1094 			continue;
1095 
1096 		status = find_p2p_bridge(func->handle, (u32)1, bus, NULL);
1097 		if (ACPI_FAILURE(status))
1098 			warn("find_p2p_bridge failed (error code = 0x%x)\n",
1099 				status);
1100 	}
1101 
1102 	slot->flags |= SLOT_ENABLED;
1103 
1104  err_exit:
1105 	return retval;
1106 }
1107 
1108 
1109 /**
1110  * disable_device - disable a slot
1111  */
1112 static int disable_device(struct acpiphp_slot *slot)
1113 {
1114 	int retval = 0;
1115 	struct acpiphp_func *func;
1116 	struct list_head *l;
1117 
1118 	/* is this slot already disabled? */
1119 	if (!(slot->flags & SLOT_ENABLED))
1120 		goto err_exit;
1121 
1122 	list_for_each (l, &slot->funcs) {
1123 		func = list_entry(l, struct acpiphp_func, sibling);
1124 
1125 		if (func->bridge) {
1126 			/* cleanup p2p bridges under this P2P bridge */
1127 			cleanup_p2p_bridge(func->bridge->handle,
1128 						(u32)1, NULL, NULL);
1129 			func->bridge = NULL;
1130 		}
1131 
1132 		acpiphp_bus_trim(func->handle);
1133 		/* try to remove anyway.
1134 		 * acpiphp_bus_add might have been failed */
1135 
1136 		if (!func->pci_dev)
1137 			continue;
1138 
1139 		pci_remove_bus_device(func->pci_dev);
1140 		pci_dev_put(func->pci_dev);
1141 		func->pci_dev = NULL;
1142 	}
1143 
1144 	slot->flags &= (~SLOT_ENABLED);
1145 
1146  err_exit:
1147 	return retval;
1148 }
1149 
1150 
1151 /**
1152  * get_slot_status - get ACPI slot status
1153  *
1154  * if a slot has _STA for each function and if any one of them
1155  * returned non-zero status, return it
1156  *
1157  * if a slot doesn't have _STA and if any one of its functions'
1158  * configuration space is configured, return 0x0f as a _STA
1159  *
1160  * otherwise return 0
1161  */
1162 static unsigned int get_slot_status(struct acpiphp_slot *slot)
1163 {
1164 	acpi_status status;
1165 	unsigned long sta = 0;
1166 	u32 dvid;
1167 	struct list_head *l;
1168 	struct acpiphp_func *func;
1169 
1170 	list_for_each (l, &slot->funcs) {
1171 		func = list_entry(l, struct acpiphp_func, sibling);
1172 
1173 		if (func->flags & FUNC_HAS_STA) {
1174 			status = acpi_evaluate_integer(func->handle, "_STA", NULL, &sta);
1175 			if (ACPI_SUCCESS(status) && sta)
1176 				break;
1177 		} else {
1178 			pci_bus_read_config_dword(slot->bridge->pci_bus,
1179 						  PCI_DEVFN(slot->device,
1180 							    func->function),
1181 						  PCI_VENDOR_ID, &dvid);
1182 			if (dvid != 0xffffffff) {
1183 				sta = ACPI_STA_ALL;
1184 				break;
1185 			}
1186 		}
1187 	}
1188 
1189 	return (unsigned int)sta;
1190 }
1191 
1192 /**
1193  * acpiphp_eject_slot - physically eject the slot
1194  */
1195 static int acpiphp_eject_slot(struct acpiphp_slot *slot)
1196 {
1197 	acpi_status status;
1198 	struct acpiphp_func *func;
1199 	struct list_head *l;
1200 	struct acpi_object_list arg_list;
1201 	union acpi_object arg;
1202 
1203 	list_for_each (l, &slot->funcs) {
1204 		func = list_entry(l, struct acpiphp_func, sibling);
1205 
1206 		/* We don't want to call _EJ0 on non-existing functions. */
1207 		if ((func->flags & FUNC_HAS_EJ0)) {
1208 			/* _EJ0 method take one argument */
1209 			arg_list.count = 1;
1210 			arg_list.pointer = &arg;
1211 			arg.type = ACPI_TYPE_INTEGER;
1212 			arg.integer.value = 1;
1213 
1214 			status = acpi_evaluate_object(func->handle, "_EJ0", &arg_list, NULL);
1215 			if (ACPI_FAILURE(status)) {
1216 				warn("%s: _EJ0 failed\n", __FUNCTION__);
1217 				return -1;
1218 			} else
1219 				break;
1220 		}
1221 	}
1222 	return 0;
1223 }
1224 
1225 /**
1226  * acpiphp_check_bridge - re-enumerate devices
1227  *
1228  * Iterate over all slots under this bridge and make sure that if a
1229  * card is present they are enabled, and if not they are disabled.
1230  */
1231 static int acpiphp_check_bridge(struct acpiphp_bridge *bridge)
1232 {
1233 	struct acpiphp_slot *slot;
1234 	int retval = 0;
1235 	int enabled, disabled;
1236 
1237 	enabled = disabled = 0;
1238 
1239 	for (slot = bridge->slots; slot; slot = slot->next) {
1240 		unsigned int status = get_slot_status(slot);
1241 		if (slot->flags & SLOT_ENABLED) {
1242 			if (status == ACPI_STA_ALL)
1243 				continue;
1244 			retval = acpiphp_disable_slot(slot);
1245 			if (retval) {
1246 				err("Error occurred in disabling\n");
1247 				goto err_exit;
1248 			} else {
1249 				acpiphp_eject_slot(slot);
1250 			}
1251 			disabled++;
1252 		} else {
1253 			if (status != ACPI_STA_ALL)
1254 				continue;
1255 			retval = acpiphp_enable_slot(slot);
1256 			if (retval) {
1257 				err("Error occurred in enabling\n");
1258 				goto err_exit;
1259 			}
1260 			enabled++;
1261 		}
1262 	}
1263 
1264 	dbg("%s: %d enabled, %d disabled\n", __FUNCTION__, enabled, disabled);
1265 
1266  err_exit:
1267 	return retval;
1268 }
1269 
1270 static void program_hpp(struct pci_dev *dev, struct acpiphp_bridge *bridge)
1271 {
1272 	u16 pci_cmd, pci_bctl;
1273 	struct pci_dev *cdev;
1274 
1275 	/* Program hpp values for this device */
1276 	if (!(dev->hdr_type == PCI_HEADER_TYPE_NORMAL ||
1277 			(dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
1278 			(dev->class >> 8) == PCI_CLASS_BRIDGE_PCI)))
1279 		return;
1280 
1281 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE,
1282 			bridge->hpp.t0->cache_line_size);
1283 	pci_write_config_byte(dev, PCI_LATENCY_TIMER,
1284 			bridge->hpp.t0->latency_timer);
1285 	pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
1286 	if (bridge->hpp.t0->enable_serr)
1287 		pci_cmd |= PCI_COMMAND_SERR;
1288 	else
1289 		pci_cmd &= ~PCI_COMMAND_SERR;
1290 	if (bridge->hpp.t0->enable_perr)
1291 		pci_cmd |= PCI_COMMAND_PARITY;
1292 	else
1293 		pci_cmd &= ~PCI_COMMAND_PARITY;
1294 	pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
1295 
1296 	/* Program bridge control value and child devices */
1297 	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
1298 		pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
1299 				bridge->hpp.t0->latency_timer);
1300 		pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
1301 		if (bridge->hpp.t0->enable_serr)
1302 			pci_bctl |= PCI_BRIDGE_CTL_SERR;
1303 		else
1304 			pci_bctl &= ~PCI_BRIDGE_CTL_SERR;
1305 		if (bridge->hpp.t0->enable_perr)
1306 			pci_bctl |= PCI_BRIDGE_CTL_PARITY;
1307 		else
1308 			pci_bctl &= ~PCI_BRIDGE_CTL_PARITY;
1309 		pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
1310 		if (dev->subordinate) {
1311 			list_for_each_entry(cdev, &dev->subordinate->devices,
1312 					bus_list)
1313 				program_hpp(cdev, bridge);
1314 		}
1315 	}
1316 }
1317 
1318 static void acpiphp_set_hpp_values(acpi_handle handle, struct pci_bus *bus)
1319 {
1320 	struct acpiphp_bridge bridge;
1321 	struct pci_dev *dev;
1322 
1323 	memset(&bridge, 0, sizeof(bridge));
1324 	bridge.handle = handle;
1325 	bridge.pci_bus = bus;
1326 	bridge.pci_dev = bus->self;
1327 	decode_hpp(&bridge);
1328 	list_for_each_entry(dev, &bus->devices, bus_list)
1329 		program_hpp(dev, &bridge);
1330 
1331 }
1332 
1333 /*
1334  * Remove devices for which we could not assign resources, call
1335  * arch specific code to fix-up the bus
1336  */
1337 static void acpiphp_sanitize_bus(struct pci_bus *bus)
1338 {
1339 	struct pci_dev *dev;
1340 	int i;
1341 	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
1342 
1343 	list_for_each_entry(dev, &bus->devices, bus_list) {
1344 		for (i=0; i<PCI_BRIDGE_RESOURCES; i++) {
1345 			struct resource *res = &dev->resource[i];
1346 			if ((res->flags & type_mask) && !res->start &&
1347 					res->end) {
1348 				/* Could not assign a required resources
1349 				 * for this device, remove it */
1350 				pci_remove_bus_device(dev);
1351 				break;
1352 			}
1353 		}
1354 	}
1355 }
1356 
1357 /* Program resources in newly inserted bridge */
1358 static int acpiphp_configure_bridge (acpi_handle handle)
1359 {
1360 	struct acpi_pci_id pci_id;
1361 	struct pci_bus *bus;
1362 
1363 	if (ACPI_FAILURE(acpi_get_pci_id(handle, &pci_id))) {
1364 		err("cannot get PCI domain and bus number for bridge\n");
1365 		return -EINVAL;
1366 	}
1367 	bus = pci_find_bus(pci_id.segment, pci_id.bus);
1368 	if (!bus) {
1369 		err("cannot find bus %d:%d\n",
1370 				pci_id.segment, pci_id.bus);
1371 		return -EINVAL;
1372 	}
1373 
1374 	pci_bus_size_bridges(bus);
1375 	pci_bus_assign_resources(bus);
1376 	acpiphp_sanitize_bus(bus);
1377 	acpiphp_set_hpp_values(handle, bus);
1378 	pci_enable_bridges(bus);
1379 	acpiphp_configure_ioapics(handle);
1380 	return 0;
1381 }
1382 
1383 static void handle_bridge_insertion(acpi_handle handle, u32 type)
1384 {
1385 	struct acpi_device *device, *pdevice;
1386 	acpi_handle phandle;
1387 
1388 	if ((type != ACPI_NOTIFY_BUS_CHECK) &&
1389 			(type != ACPI_NOTIFY_DEVICE_CHECK)) {
1390 		err("unexpected notification type %d\n", type);
1391 		return;
1392 	}
1393 
1394 	acpi_get_parent(handle, &phandle);
1395 	if (acpi_bus_get_device(phandle, &pdevice)) {
1396 		dbg("no parent device, assuming NULL\n");
1397 		pdevice = NULL;
1398 	}
1399 	if (acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE)) {
1400 		err("cannot add bridge to acpi list\n");
1401 		return;
1402 	}
1403 	if (!acpiphp_configure_bridge(handle) &&
1404 		!acpi_bus_start(device))
1405 		add_bridge(handle);
1406 	else
1407 		err("cannot configure and start bridge\n");
1408 
1409 }
1410 
1411 /*
1412  * ACPI event handlers
1413  */
1414 
1415 /**
1416  * handle_hotplug_event_bridge - handle ACPI event on bridges
1417  *
1418  * @handle: Notify()'ed acpi_handle
1419  * @type: Notify code
1420  * @context: pointer to acpiphp_bridge structure
1421  *
1422  * handles ACPI event notification on {host,p2p} bridges
1423  *
1424  */
1425 static void handle_hotplug_event_bridge(acpi_handle handle, u32 type, void *context)
1426 {
1427 	struct acpiphp_bridge *bridge;
1428 	char objname[64];
1429 	struct acpi_buffer buffer = { .length = sizeof(objname),
1430 				      .pointer = objname };
1431 	struct acpi_device *device;
1432 
1433 	if (acpi_bus_get_device(handle, &device)) {
1434 		/* This bridge must have just been physically inserted */
1435 		handle_bridge_insertion(handle, type);
1436 		return;
1437 	}
1438 
1439 	bridge = acpiphp_handle_to_bridge(handle);
1440 	if (!bridge) {
1441 		err("cannot get bridge info\n");
1442 		return;
1443 	}
1444 
1445 	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1446 
1447 	switch (type) {
1448 	case ACPI_NOTIFY_BUS_CHECK:
1449 		/* bus re-enumerate */
1450 		dbg("%s: Bus check notify on %s\n", __FUNCTION__, objname);
1451 		acpiphp_check_bridge(bridge);
1452 		break;
1453 
1454 	case ACPI_NOTIFY_DEVICE_CHECK:
1455 		/* device check */
1456 		dbg("%s: Device check notify on %s\n", __FUNCTION__, objname);
1457 		acpiphp_check_bridge(bridge);
1458 		break;
1459 
1460 	case ACPI_NOTIFY_DEVICE_WAKE:
1461 		/* wake event */
1462 		dbg("%s: Device wake notify on %s\n", __FUNCTION__, objname);
1463 		break;
1464 
1465 	case ACPI_NOTIFY_EJECT_REQUEST:
1466 		/* request device eject */
1467 		dbg("%s: Device eject notify on %s\n", __FUNCTION__, objname);
1468 		if ((bridge->type != BRIDGE_TYPE_HOST) &&
1469 		    (bridge->flags & BRIDGE_HAS_EJ0)) {
1470 			struct acpiphp_slot *slot;
1471 			slot = bridge->func->slot;
1472 			if (!acpiphp_disable_slot(slot))
1473 				acpiphp_eject_slot(slot);
1474 		}
1475 		break;
1476 
1477 	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
1478 		printk(KERN_ERR "Device %s cannot be configured due"
1479 				" to a frequency mismatch\n", objname);
1480 		break;
1481 
1482 	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
1483 		printk(KERN_ERR "Device %s cannot be configured due"
1484 				" to a bus mode mismatch\n", objname);
1485 		break;
1486 
1487 	case ACPI_NOTIFY_POWER_FAULT:
1488 		printk(KERN_ERR "Device %s has suffered a power fault\n",
1489 				objname);
1490 		break;
1491 
1492 	default:
1493 		warn("notify_handler: unknown event type 0x%x for %s\n", type, objname);
1494 		break;
1495 	}
1496 }
1497 
1498 /**
1499  * handle_hotplug_event_func - handle ACPI event on functions (i.e. slots)
1500  *
1501  * @handle: Notify()'ed acpi_handle
1502  * @type: Notify code
1503  * @context: pointer to acpiphp_func structure
1504  *
1505  * handles ACPI event notification on slots
1506  *
1507  */
1508 static void handle_hotplug_event_func(acpi_handle handle, u32 type, void *context)
1509 {
1510 	struct acpiphp_func *func;
1511 	char objname[64];
1512 	struct acpi_buffer buffer = { .length = sizeof(objname),
1513 				      .pointer = objname };
1514 
1515 	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1516 
1517 	func = (struct acpiphp_func *)context;
1518 
1519 	switch (type) {
1520 	case ACPI_NOTIFY_BUS_CHECK:
1521 		/* bus re-enumerate */
1522 		dbg("%s: Bus check notify on %s\n", __FUNCTION__, objname);
1523 		acpiphp_enable_slot(func->slot);
1524 		break;
1525 
1526 	case ACPI_NOTIFY_DEVICE_CHECK:
1527 		/* device check : re-enumerate from parent bus */
1528 		dbg("%s: Device check notify on %s\n", __FUNCTION__, objname);
1529 		acpiphp_check_bridge(func->slot->bridge);
1530 		break;
1531 
1532 	case ACPI_NOTIFY_DEVICE_WAKE:
1533 		/* wake event */
1534 		dbg("%s: Device wake notify on %s\n", __FUNCTION__, objname);
1535 		break;
1536 
1537 	case ACPI_NOTIFY_EJECT_REQUEST:
1538 		/* request device eject */
1539 		dbg("%s: Device eject notify on %s\n", __FUNCTION__, objname);
1540 		if (!(acpiphp_disable_slot(func->slot)))
1541 			acpiphp_eject_slot(func->slot);
1542 		break;
1543 
1544 	default:
1545 		warn("notify_handler: unknown event type 0x%x for %s\n", type, objname);
1546 		break;
1547 	}
1548 }
1549 
1550 
1551 static acpi_status
1552 find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
1553 {
1554 	int *count = (int *)context;
1555 
1556 	if (acpi_root_bridge(handle)) {
1557 		acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1558 				handle_hotplug_event_bridge, NULL);
1559 			(*count)++;
1560 	}
1561 	return AE_OK ;
1562 }
1563 
1564 static struct acpi_pci_driver acpi_pci_hp_driver = {
1565 	.add =		add_bridge,
1566 	.remove =	remove_bridge,
1567 };
1568 
1569 /**
1570  * acpiphp_glue_init - initializes all PCI hotplug - ACPI glue data structures
1571  *
1572  */
1573 int __init acpiphp_glue_init(void)
1574 {
1575 	int num = 0;
1576 
1577 	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
1578 			ACPI_UINT32_MAX, find_root_bridges, &num, NULL);
1579 
1580 	if (num <= 0)
1581 		return -1;
1582 	else
1583 		acpi_pci_register_driver(&acpi_pci_hp_driver);
1584 
1585 	return 0;
1586 }
1587 
1588 
1589 /**
1590  * acpiphp_glue_exit - terminates all PCI hotplug - ACPI glue data structures
1591  *
1592  * This function frees all data allocated in acpiphp_glue_init()
1593  */
1594 void __exit acpiphp_glue_exit(void)
1595 {
1596 	acpi_pci_unregister_driver(&acpi_pci_hp_driver);
1597 }
1598 
1599 
1600 /**
1601  * acpiphp_get_num_slots - count number of slots in a system
1602  */
1603 int __init acpiphp_get_num_slots(void)
1604 {
1605 	struct list_head *node;
1606 	struct acpiphp_bridge *bridge;
1607 	int num_slots;
1608 
1609 	num_slots = 0;
1610 
1611 	list_for_each (node, &bridge_list) {
1612 		bridge = (struct acpiphp_bridge *)node;
1613 		dbg("Bus %04x:%02x has %d slot%s\n",
1614 				pci_domain_nr(bridge->pci_bus),
1615 				bridge->pci_bus->number, bridge->nr_slots,
1616 				bridge->nr_slots == 1 ? "" : "s");
1617 		num_slots += bridge->nr_slots;
1618 	}
1619 
1620 	dbg("Total %d slots\n", num_slots);
1621 	return num_slots;
1622 }
1623 
1624 
1625 #if 0
1626 /**
1627  * acpiphp_for_each_slot - call function for each slot
1628  * @fn: callback function
1629  * @data: context to be passed to callback function
1630  *
1631  */
1632 static int acpiphp_for_each_slot(acpiphp_callback fn, void *data)
1633 {
1634 	struct list_head *node;
1635 	struct acpiphp_bridge *bridge;
1636 	struct acpiphp_slot *slot;
1637 	int retval = 0;
1638 
1639 	list_for_each (node, &bridge_list) {
1640 		bridge = (struct acpiphp_bridge *)node;
1641 		for (slot = bridge->slots; slot; slot = slot->next) {
1642 			retval = fn(slot, data);
1643 			if (!retval)
1644 				goto err_exit;
1645 		}
1646 	}
1647 
1648  err_exit:
1649 	return retval;
1650 }
1651 #endif
1652 
1653 
1654 /**
1655  * acpiphp_enable_slot - power on slot
1656  */
1657 int acpiphp_enable_slot(struct acpiphp_slot *slot)
1658 {
1659 	int retval;
1660 
1661 	mutex_lock(&slot->crit_sect);
1662 
1663 	/* wake up all functions */
1664 	retval = power_on_slot(slot);
1665 	if (retval)
1666 		goto err_exit;
1667 
1668 	if (get_slot_status(slot) == ACPI_STA_ALL) {
1669 		/* configure all functions */
1670 		retval = enable_device(slot);
1671 		if (retval)
1672 			power_off_slot(slot);
1673 	} else {
1674 		dbg("%s: Slot status is not ACPI_STA_ALL\n", __FUNCTION__);
1675 		power_off_slot(slot);
1676 	}
1677 
1678  err_exit:
1679 	mutex_unlock(&slot->crit_sect);
1680 	return retval;
1681 }
1682 
1683 /**
1684  * acpiphp_disable_slot - power off slot
1685  */
1686 int acpiphp_disable_slot(struct acpiphp_slot *slot)
1687 {
1688 	int retval = 0;
1689 
1690 	mutex_lock(&slot->crit_sect);
1691 
1692 	/* unconfigure all functions */
1693 	retval = disable_device(slot);
1694 	if (retval)
1695 		goto err_exit;
1696 
1697 	/* power off all functions */
1698 	retval = power_off_slot(slot);
1699 	if (retval)
1700 		goto err_exit;
1701 
1702  err_exit:
1703 	mutex_unlock(&slot->crit_sect);
1704 	return retval;
1705 }
1706 
1707 
1708 /*
1709  * slot enabled:  1
1710  * slot disabled: 0
1711  */
1712 u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
1713 {
1714 	return (slot->flags & SLOT_POWEREDON);
1715 }
1716 
1717 
1718 /*
1719  * latch closed:  1
1720  * latch   open:  0
1721  */
1722 u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
1723 {
1724 	unsigned int sta;
1725 
1726 	sta = get_slot_status(slot);
1727 
1728 	return (sta & ACPI_STA_SHOW_IN_UI) ? 1 : 0;
1729 }
1730 
1731 
1732 /*
1733  * adapter presence : 1
1734  *          absence : 0
1735  */
1736 u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
1737 {
1738 	unsigned int sta;
1739 
1740 	sta = get_slot_status(slot);
1741 
1742 	return (sta == 0) ? 0 : 1;
1743 }
1744 
1745 
1746 /*
1747  * pci address (seg/bus/dev)
1748  */
1749 u32 acpiphp_get_address(struct acpiphp_slot *slot)
1750 {
1751 	u32 address;
1752 	struct pci_bus *pci_bus = slot->bridge->pci_bus;
1753 
1754 	address = (pci_domain_nr(pci_bus) << 16) |
1755 		  (pci_bus->number << 8) |
1756 		  slot->device;
1757 
1758 	return address;
1759 }
1760