xref: /openbmc/linux/drivers/pci/pci-acpi.c (revision bc5aa3a0)
1 /*
2  * File:	pci-acpi.c
3  * Purpose:	Provide PCI support in ACPI
4  *
5  * Copyright (C) 2005 David Shaohua Li <shaohua.li@intel.com>
6  * Copyright (C) 2004 Tom Long Nguyen <tom.l.nguyen@intel.com>
7  * Copyright (C) 2004 Intel Corp.
8  */
9 
10 #include <linux/delay.h>
11 #include <linux/init.h>
12 #include <linux/irqdomain.h>
13 #include <linux/pci.h>
14 #include <linux/msi.h>
15 #include <linux/pci_hotplug.h>
16 #include <linux/module.h>
17 #include <linux/pci-aspm.h>
18 #include <linux/pci-acpi.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/pm_qos.h>
21 #include "pci.h"
22 
23 /*
24  * The UUID is defined in the PCI Firmware Specification available here:
25  * https://www.pcisig.com/members/downloads/pcifw_r3_1_13Dec10.pdf
26  */
27 const u8 pci_acpi_dsm_uuid[] = {
28 	0xd0, 0x37, 0xc9, 0xe5, 0x53, 0x35, 0x7a, 0x4d,
29 	0x91, 0x17, 0xea, 0x4d, 0x19, 0xc3, 0x43, 0x4d
30 };
31 
32 phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle)
33 {
34 	acpi_status status = AE_NOT_EXIST;
35 	unsigned long long mcfg_addr;
36 
37 	if (handle)
38 		status = acpi_evaluate_integer(handle, METHOD_NAME__CBA,
39 					       NULL, &mcfg_addr);
40 	if (ACPI_FAILURE(status))
41 		return 0;
42 
43 	return (phys_addr_t)mcfg_addr;
44 }
45 
46 static acpi_status decode_type0_hpx_record(union acpi_object *record,
47 					   struct hotplug_params *hpx)
48 {
49 	int i;
50 	union acpi_object *fields = record->package.elements;
51 	u32 revision = fields[1].integer.value;
52 
53 	switch (revision) {
54 	case 1:
55 		if (record->package.count != 6)
56 			return AE_ERROR;
57 		for (i = 2; i < 6; i++)
58 			if (fields[i].type != ACPI_TYPE_INTEGER)
59 				return AE_ERROR;
60 		hpx->t0 = &hpx->type0_data;
61 		hpx->t0->revision        = revision;
62 		hpx->t0->cache_line_size = fields[2].integer.value;
63 		hpx->t0->latency_timer   = fields[3].integer.value;
64 		hpx->t0->enable_serr     = fields[4].integer.value;
65 		hpx->t0->enable_perr     = fields[5].integer.value;
66 		break;
67 	default:
68 		printk(KERN_WARNING
69 		       "%s: Type 0 Revision %d record not supported\n",
70 		       __func__, revision);
71 		return AE_ERROR;
72 	}
73 	return AE_OK;
74 }
75 
76 static acpi_status decode_type1_hpx_record(union acpi_object *record,
77 					   struct hotplug_params *hpx)
78 {
79 	int i;
80 	union acpi_object *fields = record->package.elements;
81 	u32 revision = fields[1].integer.value;
82 
83 	switch (revision) {
84 	case 1:
85 		if (record->package.count != 5)
86 			return AE_ERROR;
87 		for (i = 2; i < 5; i++)
88 			if (fields[i].type != ACPI_TYPE_INTEGER)
89 				return AE_ERROR;
90 		hpx->t1 = &hpx->type1_data;
91 		hpx->t1->revision      = revision;
92 		hpx->t1->max_mem_read  = fields[2].integer.value;
93 		hpx->t1->avg_max_split = fields[3].integer.value;
94 		hpx->t1->tot_max_split = fields[4].integer.value;
95 		break;
96 	default:
97 		printk(KERN_WARNING
98 		       "%s: Type 1 Revision %d record not supported\n",
99 		       __func__, revision);
100 		return AE_ERROR;
101 	}
102 	return AE_OK;
103 }
104 
105 static acpi_status decode_type2_hpx_record(union acpi_object *record,
106 					   struct hotplug_params *hpx)
107 {
108 	int i;
109 	union acpi_object *fields = record->package.elements;
110 	u32 revision = fields[1].integer.value;
111 
112 	switch (revision) {
113 	case 1:
114 		if (record->package.count != 18)
115 			return AE_ERROR;
116 		for (i = 2; i < 18; i++)
117 			if (fields[i].type != ACPI_TYPE_INTEGER)
118 				return AE_ERROR;
119 		hpx->t2 = &hpx->type2_data;
120 		hpx->t2->revision      = revision;
121 		hpx->t2->unc_err_mask_and      = fields[2].integer.value;
122 		hpx->t2->unc_err_mask_or       = fields[3].integer.value;
123 		hpx->t2->unc_err_sever_and     = fields[4].integer.value;
124 		hpx->t2->unc_err_sever_or      = fields[5].integer.value;
125 		hpx->t2->cor_err_mask_and      = fields[6].integer.value;
126 		hpx->t2->cor_err_mask_or       = fields[7].integer.value;
127 		hpx->t2->adv_err_cap_and       = fields[8].integer.value;
128 		hpx->t2->adv_err_cap_or        = fields[9].integer.value;
129 		hpx->t2->pci_exp_devctl_and    = fields[10].integer.value;
130 		hpx->t2->pci_exp_devctl_or     = fields[11].integer.value;
131 		hpx->t2->pci_exp_lnkctl_and    = fields[12].integer.value;
132 		hpx->t2->pci_exp_lnkctl_or     = fields[13].integer.value;
133 		hpx->t2->sec_unc_err_sever_and = fields[14].integer.value;
134 		hpx->t2->sec_unc_err_sever_or  = fields[15].integer.value;
135 		hpx->t2->sec_unc_err_mask_and  = fields[16].integer.value;
136 		hpx->t2->sec_unc_err_mask_or   = fields[17].integer.value;
137 		break;
138 	default:
139 		printk(KERN_WARNING
140 		       "%s: Type 2 Revision %d record not supported\n",
141 		       __func__, revision);
142 		return AE_ERROR;
143 	}
144 	return AE_OK;
145 }
146 
147 static acpi_status acpi_run_hpx(acpi_handle handle, struct hotplug_params *hpx)
148 {
149 	acpi_status status;
150 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
151 	union acpi_object *package, *record, *fields;
152 	u32 type;
153 	int i;
154 
155 	/* Clear the return buffer with zeros */
156 	memset(hpx, 0, sizeof(struct hotplug_params));
157 
158 	status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer);
159 	if (ACPI_FAILURE(status))
160 		return status;
161 
162 	package = (union acpi_object *)buffer.pointer;
163 	if (package->type != ACPI_TYPE_PACKAGE) {
164 		status = AE_ERROR;
165 		goto exit;
166 	}
167 
168 	for (i = 0; i < package->package.count; i++) {
169 		record = &package->package.elements[i];
170 		if (record->type != ACPI_TYPE_PACKAGE) {
171 			status = AE_ERROR;
172 			goto exit;
173 		}
174 
175 		fields = record->package.elements;
176 		if (fields[0].type != ACPI_TYPE_INTEGER ||
177 		    fields[1].type != ACPI_TYPE_INTEGER) {
178 			status = AE_ERROR;
179 			goto exit;
180 		}
181 
182 		type = fields[0].integer.value;
183 		switch (type) {
184 		case 0:
185 			status = decode_type0_hpx_record(record, hpx);
186 			if (ACPI_FAILURE(status))
187 				goto exit;
188 			break;
189 		case 1:
190 			status = decode_type1_hpx_record(record, hpx);
191 			if (ACPI_FAILURE(status))
192 				goto exit;
193 			break;
194 		case 2:
195 			status = decode_type2_hpx_record(record, hpx);
196 			if (ACPI_FAILURE(status))
197 				goto exit;
198 			break;
199 		default:
200 			printk(KERN_ERR "%s: Type %d record not supported\n",
201 			       __func__, type);
202 			status = AE_ERROR;
203 			goto exit;
204 		}
205 	}
206  exit:
207 	kfree(buffer.pointer);
208 	return status;
209 }
210 
211 static acpi_status acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp)
212 {
213 	acpi_status status;
214 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
215 	union acpi_object *package, *fields;
216 	int i;
217 
218 	memset(hpp, 0, sizeof(struct hotplug_params));
219 
220 	status = acpi_evaluate_object(handle, "_HPP", NULL, &buffer);
221 	if (ACPI_FAILURE(status))
222 		return status;
223 
224 	package = (union acpi_object *) buffer.pointer;
225 	if (package->type != ACPI_TYPE_PACKAGE ||
226 	    package->package.count != 4) {
227 		status = AE_ERROR;
228 		goto exit;
229 	}
230 
231 	fields = package->package.elements;
232 	for (i = 0; i < 4; i++) {
233 		if (fields[i].type != ACPI_TYPE_INTEGER) {
234 			status = AE_ERROR;
235 			goto exit;
236 		}
237 	}
238 
239 	hpp->t0 = &hpp->type0_data;
240 	hpp->t0->revision        = 1;
241 	hpp->t0->cache_line_size = fields[0].integer.value;
242 	hpp->t0->latency_timer   = fields[1].integer.value;
243 	hpp->t0->enable_serr     = fields[2].integer.value;
244 	hpp->t0->enable_perr     = fields[3].integer.value;
245 
246 exit:
247 	kfree(buffer.pointer);
248 	return status;
249 }
250 
251 /* pci_get_hp_params
252  *
253  * @dev - the pci_dev for which we want parameters
254  * @hpp - allocated by the caller
255  */
256 int pci_get_hp_params(struct pci_dev *dev, struct hotplug_params *hpp)
257 {
258 	acpi_status status;
259 	acpi_handle handle, phandle;
260 	struct pci_bus *pbus;
261 
262 	if (acpi_pci_disabled)
263 		return -ENODEV;
264 
265 	handle = NULL;
266 	for (pbus = dev->bus; pbus; pbus = pbus->parent) {
267 		handle = acpi_pci_get_bridge_handle(pbus);
268 		if (handle)
269 			break;
270 	}
271 
272 	/*
273 	 * _HPP settings apply to all child buses, until another _HPP is
274 	 * encountered. If we don't find an _HPP for the input pci dev,
275 	 * look for it in the parent device scope since that would apply to
276 	 * this pci dev.
277 	 */
278 	while (handle) {
279 		status = acpi_run_hpx(handle, hpp);
280 		if (ACPI_SUCCESS(status))
281 			return 0;
282 		status = acpi_run_hpp(handle, hpp);
283 		if (ACPI_SUCCESS(status))
284 			return 0;
285 		if (acpi_is_root_bridge(handle))
286 			break;
287 		status = acpi_get_parent(handle, &phandle);
288 		if (ACPI_FAILURE(status))
289 			break;
290 		handle = phandle;
291 	}
292 	return -ENODEV;
293 }
294 EXPORT_SYMBOL_GPL(pci_get_hp_params);
295 
296 /**
297  * pci_acpi_wake_bus - Root bus wakeup notification fork function.
298  * @work: Work item to handle.
299  */
300 static void pci_acpi_wake_bus(struct work_struct *work)
301 {
302 	struct acpi_device *adev;
303 	struct acpi_pci_root *root;
304 
305 	adev = container_of(work, struct acpi_device, wakeup.context.work);
306 	root = acpi_driver_data(adev);
307 	pci_pme_wakeup_bus(root->bus);
308 }
309 
310 /**
311  * pci_acpi_wake_dev - PCI device wakeup notification work function.
312  * @handle: ACPI handle of a device the notification is for.
313  * @work: Work item to handle.
314  */
315 static void pci_acpi_wake_dev(struct work_struct *work)
316 {
317 	struct acpi_device_wakeup_context *context;
318 	struct pci_dev *pci_dev;
319 
320 	context = container_of(work, struct acpi_device_wakeup_context, work);
321 	pci_dev = to_pci_dev(context->dev);
322 
323 	if (pci_dev->pme_poll)
324 		pci_dev->pme_poll = false;
325 
326 	if (pci_dev->current_state == PCI_D3cold) {
327 		pci_wakeup_event(pci_dev);
328 		pm_runtime_resume(&pci_dev->dev);
329 		return;
330 	}
331 
332 	/* Clear PME Status if set. */
333 	if (pci_dev->pme_support)
334 		pci_check_pme_status(pci_dev);
335 
336 	pci_wakeup_event(pci_dev);
337 	pm_runtime_resume(&pci_dev->dev);
338 
339 	pci_pme_wakeup_bus(pci_dev->subordinate);
340 }
341 
342 /**
343  * pci_acpi_add_bus_pm_notifier - Register PM notifier for root PCI bus.
344  * @dev: PCI root bridge ACPI device.
345  */
346 acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev)
347 {
348 	return acpi_add_pm_notifier(dev, NULL, pci_acpi_wake_bus);
349 }
350 
351 /**
352  * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device.
353  * @dev: ACPI device to add the notifier for.
354  * @pci_dev: PCI device to check for the PME status if an event is signaled.
355  */
356 acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
357 				     struct pci_dev *pci_dev)
358 {
359 	return acpi_add_pm_notifier(dev, &pci_dev->dev, pci_acpi_wake_dev);
360 }
361 
362 /*
363  * _SxD returns the D-state with the highest power
364  * (lowest D-state number) supported in the S-state "x".
365  *
366  * If the devices does not have a _PRW
367  * (Power Resources for Wake) supporting system wakeup from "x"
368  * then the OS is free to choose a lower power (higher number
369  * D-state) than the return value from _SxD.
370  *
371  * But if _PRW is enabled at S-state "x", the OS
372  * must not choose a power lower than _SxD --
373  * unless the device has an _SxW method specifying
374  * the lowest power (highest D-state number) the device
375  * may enter while still able to wake the system.
376  *
377  * ie. depending on global OS policy:
378  *
379  * if (_PRW at S-state x)
380  *	choose from highest power _SxD to lowest power _SxW
381  * else // no _PRW at S-state x
382  *	choose highest power _SxD or any lower power
383  */
384 
385 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
386 {
387 	int acpi_state, d_max;
388 
389 	if (pdev->no_d3cold)
390 		d_max = ACPI_STATE_D3_HOT;
391 	else
392 		d_max = ACPI_STATE_D3_COLD;
393 	acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max);
394 	if (acpi_state < 0)
395 		return PCI_POWER_ERROR;
396 
397 	switch (acpi_state) {
398 	case ACPI_STATE_D0:
399 		return PCI_D0;
400 	case ACPI_STATE_D1:
401 		return PCI_D1;
402 	case ACPI_STATE_D2:
403 		return PCI_D2;
404 	case ACPI_STATE_D3_HOT:
405 		return PCI_D3hot;
406 	case ACPI_STATE_D3_COLD:
407 		return PCI_D3cold;
408 	}
409 	return PCI_POWER_ERROR;
410 }
411 
412 static bool acpi_pci_power_manageable(struct pci_dev *dev)
413 {
414 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
415 	return adev ? acpi_device_power_manageable(adev) : false;
416 }
417 
418 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
419 {
420 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
421 	static const u8 state_conv[] = {
422 		[PCI_D0] = ACPI_STATE_D0,
423 		[PCI_D1] = ACPI_STATE_D1,
424 		[PCI_D2] = ACPI_STATE_D2,
425 		[PCI_D3hot] = ACPI_STATE_D3_HOT,
426 		[PCI_D3cold] = ACPI_STATE_D3_COLD,
427 	};
428 	int error = -EINVAL;
429 
430 	/* If the ACPI device has _EJ0, ignore the device */
431 	if (!adev || acpi_has_method(adev->handle, "_EJ0"))
432 		return -ENODEV;
433 
434 	switch (state) {
435 	case PCI_D3cold:
436 		if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) ==
437 				PM_QOS_FLAGS_ALL) {
438 			error = -EBUSY;
439 			break;
440 		}
441 	case PCI_D0:
442 	case PCI_D1:
443 	case PCI_D2:
444 	case PCI_D3hot:
445 		error = acpi_device_set_power(adev, state_conv[state]);
446 	}
447 
448 	if (!error)
449 		dev_dbg(&dev->dev, "power state changed by ACPI to %s\n",
450 			 acpi_power_state_string(state_conv[state]));
451 
452 	return error;
453 }
454 
455 static bool acpi_pci_can_wakeup(struct pci_dev *dev)
456 {
457 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
458 	return adev ? acpi_device_can_wakeup(adev) : false;
459 }
460 
461 static void acpi_pci_propagate_wakeup_enable(struct pci_bus *bus, bool enable)
462 {
463 	while (bus->parent) {
464 		if (!acpi_pm_device_sleep_wake(&bus->self->dev, enable))
465 			return;
466 		bus = bus->parent;
467 	}
468 
469 	/* We have reached the root bus. */
470 	if (bus->bridge)
471 		acpi_pm_device_sleep_wake(bus->bridge, enable);
472 }
473 
474 static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
475 {
476 	if (acpi_pci_can_wakeup(dev))
477 		return acpi_pm_device_sleep_wake(&dev->dev, enable);
478 
479 	acpi_pci_propagate_wakeup_enable(dev->bus, enable);
480 	return 0;
481 }
482 
483 static void acpi_pci_propagate_run_wake(struct pci_bus *bus, bool enable)
484 {
485 	while (bus->parent) {
486 		struct pci_dev *bridge = bus->self;
487 
488 		if (bridge->pme_interrupt)
489 			return;
490 		if (!acpi_pm_device_run_wake(&bridge->dev, enable))
491 			return;
492 		bus = bus->parent;
493 	}
494 
495 	/* We have reached the root bus. */
496 	if (bus->bridge)
497 		acpi_pm_device_run_wake(bus->bridge, enable);
498 }
499 
500 static int acpi_pci_run_wake(struct pci_dev *dev, bool enable)
501 {
502 	/*
503 	 * Per PCI Express Base Specification Revision 2.0 section
504 	 * 5.3.3.2 Link Wakeup, platform support is needed for D3cold
505 	 * waking up to power on the main link even if there is PME
506 	 * support for D3cold
507 	 */
508 	if (dev->pme_interrupt && !dev->runtime_d3cold)
509 		return 0;
510 
511 	if (!acpi_pm_device_run_wake(&dev->dev, enable))
512 		return 0;
513 
514 	acpi_pci_propagate_run_wake(dev->bus, enable);
515 	return 0;
516 }
517 
518 static bool acpi_pci_need_resume(struct pci_dev *dev)
519 {
520 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
521 
522 	if (!adev || !acpi_device_power_manageable(adev))
523 		return false;
524 
525 	if (device_may_wakeup(&dev->dev) != !!adev->wakeup.prepare_count)
526 		return true;
527 
528 	if (acpi_target_system_state() == ACPI_STATE_S0)
529 		return false;
530 
531 	return !!adev->power.flags.dsw_present;
532 }
533 
534 static const struct pci_platform_pm_ops acpi_pci_platform_pm = {
535 	.is_manageable = acpi_pci_power_manageable,
536 	.set_state = acpi_pci_set_power_state,
537 	.choose_state = acpi_pci_choose_state,
538 	.sleep_wake = acpi_pci_sleep_wake,
539 	.run_wake = acpi_pci_run_wake,
540 	.need_resume = acpi_pci_need_resume,
541 };
542 
543 void acpi_pci_add_bus(struct pci_bus *bus)
544 {
545 	union acpi_object *obj;
546 	struct pci_host_bridge *bridge;
547 
548 	if (acpi_pci_disabled || !bus->bridge)
549 		return;
550 
551 	acpi_pci_slot_enumerate(bus);
552 	acpiphp_enumerate_slots(bus);
553 
554 	/*
555 	 * For a host bridge, check its _DSM for function 8 and if
556 	 * that is available, mark it in pci_host_bridge.
557 	 */
558 	if (!pci_is_root_bus(bus))
559 		return;
560 
561 	obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), pci_acpi_dsm_uuid, 3,
562 				RESET_DELAY_DSM, NULL);
563 	if (!obj)
564 		return;
565 
566 	if (obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 1) {
567 		bridge = pci_find_host_bridge(bus);
568 		bridge->ignore_reset_delay = 1;
569 	}
570 	ACPI_FREE(obj);
571 }
572 
573 void acpi_pci_remove_bus(struct pci_bus *bus)
574 {
575 	if (acpi_pci_disabled || !bus->bridge)
576 		return;
577 
578 	acpiphp_remove_slots(bus);
579 	acpi_pci_slot_remove(bus);
580 }
581 
582 /* ACPI bus type */
583 static struct acpi_device *acpi_pci_find_companion(struct device *dev)
584 {
585 	struct pci_dev *pci_dev = to_pci_dev(dev);
586 	bool check_children;
587 	u64 addr;
588 
589 	check_children = pci_is_bridge(pci_dev);
590 	/* Please ref to ACPI spec for the syntax of _ADR */
591 	addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
592 	return acpi_find_child_device(ACPI_COMPANION(dev->parent), addr,
593 				      check_children);
594 }
595 
596 /**
597  * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI
598  * @pdev: the PCI device whose delay is to be updated
599  * @handle: ACPI handle of this device
600  *
601  * Update the d3_delay and d3cold_delay of a PCI device from the ACPI _DSM
602  * control method of either the device itself or the PCI host bridge.
603  *
604  * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI
605  * host bridge.  If it returns one, the OS may assume that all devices in
606  * the hierarchy have already completed power-on reset delays.
607  *
608  * Function 9, "Device Readiness Durations," applies only to the object
609  * where it is located.  It returns delay durations required after various
610  * events if the device requires less time than the spec requires.  Delays
611  * from this function take precedence over the Reset Delay function.
612  *
613  * These _DSM functions are defined by the draft ECN of January 28, 2014,
614  * titled "ACPI additions for FW latency optimizations."
615  */
616 static void pci_acpi_optimize_delay(struct pci_dev *pdev,
617 				    acpi_handle handle)
618 {
619 	struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
620 	int value;
621 	union acpi_object *obj, *elements;
622 
623 	if (bridge->ignore_reset_delay)
624 		pdev->d3cold_delay = 0;
625 
626 	obj = acpi_evaluate_dsm(handle, pci_acpi_dsm_uuid, 3,
627 				FUNCTION_DELAY_DSM, NULL);
628 	if (!obj)
629 		return;
630 
631 	if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) {
632 		elements = obj->package.elements;
633 		if (elements[0].type == ACPI_TYPE_INTEGER) {
634 			value = (int)elements[0].integer.value / 1000;
635 			if (value < PCI_PM_D3COLD_WAIT)
636 				pdev->d3cold_delay = value;
637 		}
638 		if (elements[3].type == ACPI_TYPE_INTEGER) {
639 			value = (int)elements[3].integer.value / 1000;
640 			if (value < PCI_PM_D3_WAIT)
641 				pdev->d3_delay = value;
642 		}
643 	}
644 	ACPI_FREE(obj);
645 }
646 
647 static void pci_acpi_setup(struct device *dev)
648 {
649 	struct pci_dev *pci_dev = to_pci_dev(dev);
650 	struct acpi_device *adev = ACPI_COMPANION(dev);
651 
652 	if (!adev)
653 		return;
654 
655 	pci_acpi_optimize_delay(pci_dev, adev->handle);
656 
657 	pci_acpi_add_pm_notifier(adev, pci_dev);
658 	if (!adev->wakeup.flags.valid)
659 		return;
660 
661 	device_set_wakeup_capable(dev, true);
662 	acpi_pci_sleep_wake(pci_dev, false);
663 	if (adev->wakeup.flags.run_wake)
664 		device_set_run_wake(dev, true);
665 }
666 
667 static void pci_acpi_cleanup(struct device *dev)
668 {
669 	struct acpi_device *adev = ACPI_COMPANION(dev);
670 
671 	if (!adev)
672 		return;
673 
674 	pci_acpi_remove_pm_notifier(adev);
675 	if (adev->wakeup.flags.valid) {
676 		device_set_wakeup_capable(dev, false);
677 		device_set_run_wake(dev, false);
678 	}
679 }
680 
681 static bool pci_acpi_bus_match(struct device *dev)
682 {
683 	return dev_is_pci(dev);
684 }
685 
686 static struct acpi_bus_type acpi_pci_bus = {
687 	.name = "PCI",
688 	.match = pci_acpi_bus_match,
689 	.find_companion = acpi_pci_find_companion,
690 	.setup = pci_acpi_setup,
691 	.cleanup = pci_acpi_cleanup,
692 };
693 
694 
695 static struct fwnode_handle *(*pci_msi_get_fwnode_cb)(struct device *dev);
696 
697 /**
698  * pci_msi_register_fwnode_provider - Register callback to retrieve fwnode
699  * @fn:       Callback matching a device to a fwnode that identifies a PCI
700  *            MSI domain.
701  *
702  * This should be called by irqchip driver, which is the parent of
703  * the MSI domain to provide callback interface to query fwnode.
704  */
705 void
706 pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *))
707 {
708 	pci_msi_get_fwnode_cb = fn;
709 }
710 
711 /**
712  * pci_host_bridge_acpi_msi_domain - Retrieve MSI domain of a PCI host bridge
713  * @bus:      The PCI host bridge bus.
714  *
715  * This function uses the callback function registered by
716  * pci_msi_register_fwnode_provider() to retrieve the irq_domain with
717  * type DOMAIN_BUS_PCI_MSI of the specified host bridge bus.
718  * This returns NULL on error or when the domain is not found.
719  */
720 struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus)
721 {
722 	struct fwnode_handle *fwnode;
723 
724 	if (!pci_msi_get_fwnode_cb)
725 		return NULL;
726 
727 	fwnode = pci_msi_get_fwnode_cb(&bus->dev);
728 	if (!fwnode)
729 		return NULL;
730 
731 	return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI);
732 }
733 
734 static int __init acpi_pci_init(void)
735 {
736 	int ret;
737 
738 	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) {
739 		pr_info("ACPI FADT declares the system doesn't support MSI, so disable it\n");
740 		pci_no_msi();
741 	}
742 
743 	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
744 		pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
745 		pcie_no_aspm();
746 	}
747 
748 	ret = register_acpi_bus_type(&acpi_pci_bus);
749 	if (ret)
750 		return 0;
751 
752 	pci_set_platform_pm(&acpi_pci_platform_pm);
753 	acpi_pci_slot_init();
754 	acpiphp_init();
755 
756 	return 0;
757 }
758 arch_initcall(acpi_pci_init);
759