xref: /linux/drivers/pci/pci-acpi.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
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 #if defined(CONFIG_PCI_QUIRKS) && defined(CONFIG_ARM64)
33 static int acpi_get_rc_addr(struct acpi_device *adev, struct resource *res)
34 {
35 	struct device *dev = &adev->dev;
36 	struct resource_entry *entry;
37 	struct list_head list;
38 	unsigned long flags;
39 	int ret;
40 
41 	INIT_LIST_HEAD(&list);
42 	flags = IORESOURCE_MEM;
43 	ret = acpi_dev_get_resources(adev, &list,
44 				     acpi_dev_filter_resource_type_cb,
45 				     (void *) flags);
46 	if (ret < 0) {
47 		dev_err(dev, "failed to parse _CRS method, error code %d\n",
48 			ret);
49 		return ret;
50 	}
51 
52 	if (ret == 0) {
53 		dev_err(dev, "no IO and memory resources present in _CRS\n");
54 		return -EINVAL;
55 	}
56 
57 	entry = list_first_entry(&list, struct resource_entry, node);
58 	*res = *entry->res;
59 	acpi_dev_free_resource_list(&list);
60 	return 0;
61 }
62 
63 static acpi_status acpi_match_rc(acpi_handle handle, u32 lvl, void *context,
64 				 void **retval)
65 {
66 	u16 *segment = context;
67 	unsigned long long uid;
68 	acpi_status status;
69 
70 	status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
71 	if (ACPI_FAILURE(status) || uid != *segment)
72 		return AE_CTRL_DEPTH;
73 
74 	*(acpi_handle *)retval = handle;
75 	return AE_CTRL_TERMINATE;
76 }
77 
78 int acpi_get_rc_resources(struct device *dev, const char *hid, u16 segment,
79 			  struct resource *res)
80 {
81 	struct acpi_device *adev;
82 	acpi_status status;
83 	acpi_handle handle;
84 	int ret;
85 
86 	status = acpi_get_devices(hid, acpi_match_rc, &segment, &handle);
87 	if (ACPI_FAILURE(status)) {
88 		dev_err(dev, "can't find _HID %s device to locate resources\n",
89 			hid);
90 		return -ENODEV;
91 	}
92 
93 	ret = acpi_bus_get_device(handle, &adev);
94 	if (ret)
95 		return ret;
96 
97 	ret = acpi_get_rc_addr(adev, res);
98 	if (ret) {
99 		dev_err(dev, "can't get resource from %s\n",
100 			dev_name(&adev->dev));
101 		return ret;
102 	}
103 
104 	return 0;
105 }
106 #endif
107 
108 phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle)
109 {
110 	acpi_status status = AE_NOT_EXIST;
111 	unsigned long long mcfg_addr;
112 
113 	if (handle)
114 		status = acpi_evaluate_integer(handle, METHOD_NAME__CBA,
115 					       NULL, &mcfg_addr);
116 	if (ACPI_FAILURE(status))
117 		return 0;
118 
119 	return (phys_addr_t)mcfg_addr;
120 }
121 
122 static acpi_status decode_type0_hpx_record(union acpi_object *record,
123 					   struct hotplug_params *hpx)
124 {
125 	int i;
126 	union acpi_object *fields = record->package.elements;
127 	u32 revision = fields[1].integer.value;
128 
129 	switch (revision) {
130 	case 1:
131 		if (record->package.count != 6)
132 			return AE_ERROR;
133 		for (i = 2; i < 6; i++)
134 			if (fields[i].type != ACPI_TYPE_INTEGER)
135 				return AE_ERROR;
136 		hpx->t0 = &hpx->type0_data;
137 		hpx->t0->revision        = revision;
138 		hpx->t0->cache_line_size = fields[2].integer.value;
139 		hpx->t0->latency_timer   = fields[3].integer.value;
140 		hpx->t0->enable_serr     = fields[4].integer.value;
141 		hpx->t0->enable_perr     = fields[5].integer.value;
142 		break;
143 	default:
144 		printk(KERN_WARNING
145 		       "%s: Type 0 Revision %d record not supported\n",
146 		       __func__, revision);
147 		return AE_ERROR;
148 	}
149 	return AE_OK;
150 }
151 
152 static acpi_status decode_type1_hpx_record(union acpi_object *record,
153 					   struct hotplug_params *hpx)
154 {
155 	int i;
156 	union acpi_object *fields = record->package.elements;
157 	u32 revision = fields[1].integer.value;
158 
159 	switch (revision) {
160 	case 1:
161 		if (record->package.count != 5)
162 			return AE_ERROR;
163 		for (i = 2; i < 5; i++)
164 			if (fields[i].type != ACPI_TYPE_INTEGER)
165 				return AE_ERROR;
166 		hpx->t1 = &hpx->type1_data;
167 		hpx->t1->revision      = revision;
168 		hpx->t1->max_mem_read  = fields[2].integer.value;
169 		hpx->t1->avg_max_split = fields[3].integer.value;
170 		hpx->t1->tot_max_split = fields[4].integer.value;
171 		break;
172 	default:
173 		printk(KERN_WARNING
174 		       "%s: Type 1 Revision %d record not supported\n",
175 		       __func__, revision);
176 		return AE_ERROR;
177 	}
178 	return AE_OK;
179 }
180 
181 static acpi_status decode_type2_hpx_record(union acpi_object *record,
182 					   struct hotplug_params *hpx)
183 {
184 	int i;
185 	union acpi_object *fields = record->package.elements;
186 	u32 revision = fields[1].integer.value;
187 
188 	switch (revision) {
189 	case 1:
190 		if (record->package.count != 18)
191 			return AE_ERROR;
192 		for (i = 2; i < 18; i++)
193 			if (fields[i].type != ACPI_TYPE_INTEGER)
194 				return AE_ERROR;
195 		hpx->t2 = &hpx->type2_data;
196 		hpx->t2->revision      = revision;
197 		hpx->t2->unc_err_mask_and      = fields[2].integer.value;
198 		hpx->t2->unc_err_mask_or       = fields[3].integer.value;
199 		hpx->t2->unc_err_sever_and     = fields[4].integer.value;
200 		hpx->t2->unc_err_sever_or      = fields[5].integer.value;
201 		hpx->t2->cor_err_mask_and      = fields[6].integer.value;
202 		hpx->t2->cor_err_mask_or       = fields[7].integer.value;
203 		hpx->t2->adv_err_cap_and       = fields[8].integer.value;
204 		hpx->t2->adv_err_cap_or        = fields[9].integer.value;
205 		hpx->t2->pci_exp_devctl_and    = fields[10].integer.value;
206 		hpx->t2->pci_exp_devctl_or     = fields[11].integer.value;
207 		hpx->t2->pci_exp_lnkctl_and    = fields[12].integer.value;
208 		hpx->t2->pci_exp_lnkctl_or     = fields[13].integer.value;
209 		hpx->t2->sec_unc_err_sever_and = fields[14].integer.value;
210 		hpx->t2->sec_unc_err_sever_or  = fields[15].integer.value;
211 		hpx->t2->sec_unc_err_mask_and  = fields[16].integer.value;
212 		hpx->t2->sec_unc_err_mask_or   = fields[17].integer.value;
213 		break;
214 	default:
215 		printk(KERN_WARNING
216 		       "%s: Type 2 Revision %d record not supported\n",
217 		       __func__, revision);
218 		return AE_ERROR;
219 	}
220 	return AE_OK;
221 }
222 
223 static acpi_status acpi_run_hpx(acpi_handle handle, struct hotplug_params *hpx)
224 {
225 	acpi_status status;
226 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
227 	union acpi_object *package, *record, *fields;
228 	u32 type;
229 	int i;
230 
231 	/* Clear the return buffer with zeros */
232 	memset(hpx, 0, sizeof(struct hotplug_params));
233 
234 	status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer);
235 	if (ACPI_FAILURE(status))
236 		return status;
237 
238 	package = (union acpi_object *)buffer.pointer;
239 	if (package->type != ACPI_TYPE_PACKAGE) {
240 		status = AE_ERROR;
241 		goto exit;
242 	}
243 
244 	for (i = 0; i < package->package.count; i++) {
245 		record = &package->package.elements[i];
246 		if (record->type != ACPI_TYPE_PACKAGE) {
247 			status = AE_ERROR;
248 			goto exit;
249 		}
250 
251 		fields = record->package.elements;
252 		if (fields[0].type != ACPI_TYPE_INTEGER ||
253 		    fields[1].type != ACPI_TYPE_INTEGER) {
254 			status = AE_ERROR;
255 			goto exit;
256 		}
257 
258 		type = fields[0].integer.value;
259 		switch (type) {
260 		case 0:
261 			status = decode_type0_hpx_record(record, hpx);
262 			if (ACPI_FAILURE(status))
263 				goto exit;
264 			break;
265 		case 1:
266 			status = decode_type1_hpx_record(record, hpx);
267 			if (ACPI_FAILURE(status))
268 				goto exit;
269 			break;
270 		case 2:
271 			status = decode_type2_hpx_record(record, hpx);
272 			if (ACPI_FAILURE(status))
273 				goto exit;
274 			break;
275 		default:
276 			printk(KERN_ERR "%s: Type %d record not supported\n",
277 			       __func__, type);
278 			status = AE_ERROR;
279 			goto exit;
280 		}
281 	}
282  exit:
283 	kfree(buffer.pointer);
284 	return status;
285 }
286 
287 static acpi_status acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp)
288 {
289 	acpi_status status;
290 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
291 	union acpi_object *package, *fields;
292 	int i;
293 
294 	memset(hpp, 0, sizeof(struct hotplug_params));
295 
296 	status = acpi_evaluate_object(handle, "_HPP", NULL, &buffer);
297 	if (ACPI_FAILURE(status))
298 		return status;
299 
300 	package = (union acpi_object *) buffer.pointer;
301 	if (package->type != ACPI_TYPE_PACKAGE ||
302 	    package->package.count != 4) {
303 		status = AE_ERROR;
304 		goto exit;
305 	}
306 
307 	fields = package->package.elements;
308 	for (i = 0; i < 4; i++) {
309 		if (fields[i].type != ACPI_TYPE_INTEGER) {
310 			status = AE_ERROR;
311 			goto exit;
312 		}
313 	}
314 
315 	hpp->t0 = &hpp->type0_data;
316 	hpp->t0->revision        = 1;
317 	hpp->t0->cache_line_size = fields[0].integer.value;
318 	hpp->t0->latency_timer   = fields[1].integer.value;
319 	hpp->t0->enable_serr     = fields[2].integer.value;
320 	hpp->t0->enable_perr     = fields[3].integer.value;
321 
322 exit:
323 	kfree(buffer.pointer);
324 	return status;
325 }
326 
327 /* pci_get_hp_params
328  *
329  * @dev - the pci_dev for which we want parameters
330  * @hpp - allocated by the caller
331  */
332 int pci_get_hp_params(struct pci_dev *dev, struct hotplug_params *hpp)
333 {
334 	acpi_status status;
335 	acpi_handle handle, phandle;
336 	struct pci_bus *pbus;
337 
338 	if (acpi_pci_disabled)
339 		return -ENODEV;
340 
341 	handle = NULL;
342 	for (pbus = dev->bus; pbus; pbus = pbus->parent) {
343 		handle = acpi_pci_get_bridge_handle(pbus);
344 		if (handle)
345 			break;
346 	}
347 
348 	/*
349 	 * _HPP settings apply to all child buses, until another _HPP is
350 	 * encountered. If we don't find an _HPP for the input pci dev,
351 	 * look for it in the parent device scope since that would apply to
352 	 * this pci dev.
353 	 */
354 	while (handle) {
355 		status = acpi_run_hpx(handle, hpp);
356 		if (ACPI_SUCCESS(status))
357 			return 0;
358 		status = acpi_run_hpp(handle, hpp);
359 		if (ACPI_SUCCESS(status))
360 			return 0;
361 		if (acpi_is_root_bridge(handle))
362 			break;
363 		status = acpi_get_parent(handle, &phandle);
364 		if (ACPI_FAILURE(status))
365 			break;
366 		handle = phandle;
367 	}
368 	return -ENODEV;
369 }
370 EXPORT_SYMBOL_GPL(pci_get_hp_params);
371 
372 /**
373  * pciehp_is_native - Check whether a hotplug port is handled by the OS
374  * @pdev: Hotplug port to check
375  *
376  * Walk up from @pdev to the host bridge, obtain its cached _OSC Control Field
377  * and return the value of the "PCI Express Native Hot Plug control" bit.
378  * On failure to obtain the _OSC Control Field return %false.
379  */
380 bool pciehp_is_native(struct pci_dev *pdev)
381 {
382 	struct acpi_pci_root *root;
383 	acpi_handle handle;
384 
385 	handle = acpi_find_root_bridge_handle(pdev);
386 	if (!handle)
387 		return false;
388 
389 	root = acpi_pci_find_root(handle);
390 	if (!root)
391 		return false;
392 
393 	return root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
394 }
395 
396 /**
397  * pci_acpi_wake_bus - Root bus wakeup notification fork function.
398  * @work: Work item to handle.
399  */
400 static void pci_acpi_wake_bus(struct work_struct *work)
401 {
402 	struct acpi_device *adev;
403 	struct acpi_pci_root *root;
404 
405 	adev = container_of(work, struct acpi_device, wakeup.context.work);
406 	root = acpi_driver_data(adev);
407 	pci_pme_wakeup_bus(root->bus);
408 }
409 
410 /**
411  * pci_acpi_wake_dev - PCI device wakeup notification work function.
412  * @handle: ACPI handle of a device the notification is for.
413  * @work: Work item to handle.
414  */
415 static void pci_acpi_wake_dev(struct work_struct *work)
416 {
417 	struct acpi_device_wakeup_context *context;
418 	struct pci_dev *pci_dev;
419 
420 	context = container_of(work, struct acpi_device_wakeup_context, work);
421 	pci_dev = to_pci_dev(context->dev);
422 
423 	if (pci_dev->pme_poll)
424 		pci_dev->pme_poll = false;
425 
426 	if (pci_dev->current_state == PCI_D3cold) {
427 		pci_wakeup_event(pci_dev);
428 		pm_runtime_resume(&pci_dev->dev);
429 		return;
430 	}
431 
432 	/* Clear PME Status if set. */
433 	if (pci_dev->pme_support)
434 		pci_check_pme_status(pci_dev);
435 
436 	pci_wakeup_event(pci_dev);
437 	pm_runtime_resume(&pci_dev->dev);
438 
439 	pci_pme_wakeup_bus(pci_dev->subordinate);
440 }
441 
442 /**
443  * pci_acpi_add_bus_pm_notifier - Register PM notifier for root PCI bus.
444  * @dev: PCI root bridge ACPI device.
445  */
446 acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev)
447 {
448 	return acpi_add_pm_notifier(dev, NULL, pci_acpi_wake_bus);
449 }
450 
451 /**
452  * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device.
453  * @dev: ACPI device to add the notifier for.
454  * @pci_dev: PCI device to check for the PME status if an event is signaled.
455  */
456 acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
457 				     struct pci_dev *pci_dev)
458 {
459 	return acpi_add_pm_notifier(dev, &pci_dev->dev, pci_acpi_wake_dev);
460 }
461 
462 /*
463  * _SxD returns the D-state with the highest power
464  * (lowest D-state number) supported in the S-state "x".
465  *
466  * If the devices does not have a _PRW
467  * (Power Resources for Wake) supporting system wakeup from "x"
468  * then the OS is free to choose a lower power (higher number
469  * D-state) than the return value from _SxD.
470  *
471  * But if _PRW is enabled at S-state "x", the OS
472  * must not choose a power lower than _SxD --
473  * unless the device has an _SxW method specifying
474  * the lowest power (highest D-state number) the device
475  * may enter while still able to wake the system.
476  *
477  * ie. depending on global OS policy:
478  *
479  * if (_PRW at S-state x)
480  *	choose from highest power _SxD to lowest power _SxW
481  * else // no _PRW at S-state x
482  *	choose highest power _SxD or any lower power
483  */
484 
485 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
486 {
487 	int acpi_state, d_max;
488 
489 	if (pdev->no_d3cold)
490 		d_max = ACPI_STATE_D3_HOT;
491 	else
492 		d_max = ACPI_STATE_D3_COLD;
493 	acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max);
494 	if (acpi_state < 0)
495 		return PCI_POWER_ERROR;
496 
497 	switch (acpi_state) {
498 	case ACPI_STATE_D0:
499 		return PCI_D0;
500 	case ACPI_STATE_D1:
501 		return PCI_D1;
502 	case ACPI_STATE_D2:
503 		return PCI_D2;
504 	case ACPI_STATE_D3_HOT:
505 		return PCI_D3hot;
506 	case ACPI_STATE_D3_COLD:
507 		return PCI_D3cold;
508 	}
509 	return PCI_POWER_ERROR;
510 }
511 
512 static bool acpi_pci_power_manageable(struct pci_dev *dev)
513 {
514 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
515 	return adev ? acpi_device_power_manageable(adev) : false;
516 }
517 
518 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
519 {
520 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
521 	static const u8 state_conv[] = {
522 		[PCI_D0] = ACPI_STATE_D0,
523 		[PCI_D1] = ACPI_STATE_D1,
524 		[PCI_D2] = ACPI_STATE_D2,
525 		[PCI_D3hot] = ACPI_STATE_D3_HOT,
526 		[PCI_D3cold] = ACPI_STATE_D3_COLD,
527 	};
528 	int error = -EINVAL;
529 
530 	/* If the ACPI device has _EJ0, ignore the device */
531 	if (!adev || acpi_has_method(adev->handle, "_EJ0"))
532 		return -ENODEV;
533 
534 	switch (state) {
535 	case PCI_D3cold:
536 		if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) ==
537 				PM_QOS_FLAGS_ALL) {
538 			error = -EBUSY;
539 			break;
540 		}
541 	case PCI_D0:
542 	case PCI_D1:
543 	case PCI_D2:
544 	case PCI_D3hot:
545 		error = acpi_device_set_power(adev, state_conv[state]);
546 	}
547 
548 	if (!error)
549 		dev_dbg(&dev->dev, "power state changed by ACPI to %s\n",
550 			 acpi_power_state_string(state_conv[state]));
551 
552 	return error;
553 }
554 
555 static pci_power_t acpi_pci_get_power_state(struct pci_dev *dev)
556 {
557 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
558 	static const pci_power_t state_conv[] = {
559 		[ACPI_STATE_D0]      = PCI_D0,
560 		[ACPI_STATE_D1]      = PCI_D1,
561 		[ACPI_STATE_D2]      = PCI_D2,
562 		[ACPI_STATE_D3_HOT]  = PCI_D3hot,
563 		[ACPI_STATE_D3_COLD] = PCI_D3cold,
564 	};
565 	int state;
566 
567 	if (!adev || !acpi_device_power_manageable(adev))
568 		return PCI_UNKNOWN;
569 
570 	if (acpi_device_get_power(adev, &state) || state == ACPI_STATE_UNKNOWN)
571 		return PCI_UNKNOWN;
572 
573 	return state_conv[state];
574 }
575 
576 static bool acpi_pci_can_wakeup(struct pci_dev *dev)
577 {
578 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
579 	return adev ? acpi_device_can_wakeup(adev) : false;
580 }
581 
582 static void acpi_pci_propagate_wakeup_enable(struct pci_bus *bus, bool enable)
583 {
584 	while (bus->parent) {
585 		if (!acpi_pm_device_sleep_wake(&bus->self->dev, enable))
586 			return;
587 		bus = bus->parent;
588 	}
589 
590 	/* We have reached the root bus. */
591 	if (bus->bridge)
592 		acpi_pm_device_sleep_wake(bus->bridge, enable);
593 }
594 
595 static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
596 {
597 	if (acpi_pci_can_wakeup(dev))
598 		return acpi_pm_device_sleep_wake(&dev->dev, enable);
599 
600 	acpi_pci_propagate_wakeup_enable(dev->bus, enable);
601 	return 0;
602 }
603 
604 static void acpi_pci_propagate_run_wake(struct pci_bus *bus, bool enable)
605 {
606 	while (bus->parent) {
607 		struct pci_dev *bridge = bus->self;
608 
609 		if (bridge->pme_interrupt)
610 			return;
611 		if (!acpi_pm_device_run_wake(&bridge->dev, enable))
612 			return;
613 		bus = bus->parent;
614 	}
615 
616 	/* We have reached the root bus. */
617 	if (bus->bridge)
618 		acpi_pm_device_run_wake(bus->bridge, enable);
619 }
620 
621 static int acpi_pci_run_wake(struct pci_dev *dev, bool enable)
622 {
623 	/*
624 	 * Per PCI Express Base Specification Revision 2.0 section
625 	 * 5.3.3.2 Link Wakeup, platform support is needed for D3cold
626 	 * waking up to power on the main link even if there is PME
627 	 * support for D3cold
628 	 */
629 	if (dev->pme_interrupt && !dev->runtime_d3cold)
630 		return 0;
631 
632 	if (!acpi_pm_device_run_wake(&dev->dev, enable))
633 		return 0;
634 
635 	acpi_pci_propagate_run_wake(dev->bus, enable);
636 	return 0;
637 }
638 
639 static bool acpi_pci_need_resume(struct pci_dev *dev)
640 {
641 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
642 
643 	if (!adev || !acpi_device_power_manageable(adev))
644 		return false;
645 
646 	if (device_may_wakeup(&dev->dev) != !!adev->wakeup.prepare_count)
647 		return true;
648 
649 	if (acpi_target_system_state() == ACPI_STATE_S0)
650 		return false;
651 
652 	return !!adev->power.flags.dsw_present;
653 }
654 
655 static const struct pci_platform_pm_ops acpi_pci_platform_pm = {
656 	.is_manageable = acpi_pci_power_manageable,
657 	.set_state = acpi_pci_set_power_state,
658 	.get_state = acpi_pci_get_power_state,
659 	.choose_state = acpi_pci_choose_state,
660 	.sleep_wake = acpi_pci_sleep_wake,
661 	.run_wake = acpi_pci_run_wake,
662 	.need_resume = acpi_pci_need_resume,
663 };
664 
665 void acpi_pci_add_bus(struct pci_bus *bus)
666 {
667 	union acpi_object *obj;
668 	struct pci_host_bridge *bridge;
669 
670 	if (acpi_pci_disabled || !bus->bridge)
671 		return;
672 
673 	acpi_pci_slot_enumerate(bus);
674 	acpiphp_enumerate_slots(bus);
675 
676 	/*
677 	 * For a host bridge, check its _DSM for function 8 and if
678 	 * that is available, mark it in pci_host_bridge.
679 	 */
680 	if (!pci_is_root_bus(bus))
681 		return;
682 
683 	obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), pci_acpi_dsm_uuid, 3,
684 				RESET_DELAY_DSM, NULL);
685 	if (!obj)
686 		return;
687 
688 	if (obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 1) {
689 		bridge = pci_find_host_bridge(bus);
690 		bridge->ignore_reset_delay = 1;
691 	}
692 	ACPI_FREE(obj);
693 }
694 
695 void acpi_pci_remove_bus(struct pci_bus *bus)
696 {
697 	if (acpi_pci_disabled || !bus->bridge)
698 		return;
699 
700 	acpiphp_remove_slots(bus);
701 	acpi_pci_slot_remove(bus);
702 }
703 
704 /* ACPI bus type */
705 static struct acpi_device *acpi_pci_find_companion(struct device *dev)
706 {
707 	struct pci_dev *pci_dev = to_pci_dev(dev);
708 	bool check_children;
709 	u64 addr;
710 
711 	check_children = pci_is_bridge(pci_dev);
712 	/* Please ref to ACPI spec for the syntax of _ADR */
713 	addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
714 	return acpi_find_child_device(ACPI_COMPANION(dev->parent), addr,
715 				      check_children);
716 }
717 
718 /**
719  * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI
720  * @pdev: the PCI device whose delay is to be updated
721  * @handle: ACPI handle of this device
722  *
723  * Update the d3_delay and d3cold_delay of a PCI device from the ACPI _DSM
724  * control method of either the device itself or the PCI host bridge.
725  *
726  * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI
727  * host bridge.  If it returns one, the OS may assume that all devices in
728  * the hierarchy have already completed power-on reset delays.
729  *
730  * Function 9, "Device Readiness Durations," applies only to the object
731  * where it is located.  It returns delay durations required after various
732  * events if the device requires less time than the spec requires.  Delays
733  * from this function take precedence over the Reset Delay function.
734  *
735  * These _DSM functions are defined by the draft ECN of January 28, 2014,
736  * titled "ACPI additions for FW latency optimizations."
737  */
738 static void pci_acpi_optimize_delay(struct pci_dev *pdev,
739 				    acpi_handle handle)
740 {
741 	struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
742 	int value;
743 	union acpi_object *obj, *elements;
744 
745 	if (bridge->ignore_reset_delay)
746 		pdev->d3cold_delay = 0;
747 
748 	obj = acpi_evaluate_dsm(handle, pci_acpi_dsm_uuid, 3,
749 				FUNCTION_DELAY_DSM, NULL);
750 	if (!obj)
751 		return;
752 
753 	if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) {
754 		elements = obj->package.elements;
755 		if (elements[0].type == ACPI_TYPE_INTEGER) {
756 			value = (int)elements[0].integer.value / 1000;
757 			if (value < PCI_PM_D3COLD_WAIT)
758 				pdev->d3cold_delay = value;
759 		}
760 		if (elements[3].type == ACPI_TYPE_INTEGER) {
761 			value = (int)elements[3].integer.value / 1000;
762 			if (value < PCI_PM_D3_WAIT)
763 				pdev->d3_delay = value;
764 		}
765 	}
766 	ACPI_FREE(obj);
767 }
768 
769 static void pci_acpi_setup(struct device *dev)
770 {
771 	struct pci_dev *pci_dev = to_pci_dev(dev);
772 	struct acpi_device *adev = ACPI_COMPANION(dev);
773 
774 	if (!adev)
775 		return;
776 
777 	pci_acpi_optimize_delay(pci_dev, adev->handle);
778 
779 	pci_acpi_add_pm_notifier(adev, pci_dev);
780 	if (!adev->wakeup.flags.valid)
781 		return;
782 
783 	device_set_wakeup_capable(dev, true);
784 	acpi_pci_sleep_wake(pci_dev, false);
785 	if (adev->wakeup.flags.run_wake)
786 		device_set_run_wake(dev, true);
787 }
788 
789 static void pci_acpi_cleanup(struct device *dev)
790 {
791 	struct acpi_device *adev = ACPI_COMPANION(dev);
792 
793 	if (!adev)
794 		return;
795 
796 	pci_acpi_remove_pm_notifier(adev);
797 	if (adev->wakeup.flags.valid) {
798 		device_set_wakeup_capable(dev, false);
799 		device_set_run_wake(dev, false);
800 	}
801 }
802 
803 static bool pci_acpi_bus_match(struct device *dev)
804 {
805 	return dev_is_pci(dev);
806 }
807 
808 static struct acpi_bus_type acpi_pci_bus = {
809 	.name = "PCI",
810 	.match = pci_acpi_bus_match,
811 	.find_companion = acpi_pci_find_companion,
812 	.setup = pci_acpi_setup,
813 	.cleanup = pci_acpi_cleanup,
814 };
815 
816 
817 static struct fwnode_handle *(*pci_msi_get_fwnode_cb)(struct device *dev);
818 
819 /**
820  * pci_msi_register_fwnode_provider - Register callback to retrieve fwnode
821  * @fn:       Callback matching a device to a fwnode that identifies a PCI
822  *            MSI domain.
823  *
824  * This should be called by irqchip driver, which is the parent of
825  * the MSI domain to provide callback interface to query fwnode.
826  */
827 void
828 pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *))
829 {
830 	pci_msi_get_fwnode_cb = fn;
831 }
832 
833 /**
834  * pci_host_bridge_acpi_msi_domain - Retrieve MSI domain of a PCI host bridge
835  * @bus:      The PCI host bridge bus.
836  *
837  * This function uses the callback function registered by
838  * pci_msi_register_fwnode_provider() to retrieve the irq_domain with
839  * type DOMAIN_BUS_PCI_MSI of the specified host bridge bus.
840  * This returns NULL on error or when the domain is not found.
841  */
842 struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus)
843 {
844 	struct fwnode_handle *fwnode;
845 
846 	if (!pci_msi_get_fwnode_cb)
847 		return NULL;
848 
849 	fwnode = pci_msi_get_fwnode_cb(&bus->dev);
850 	if (!fwnode)
851 		return NULL;
852 
853 	return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI);
854 }
855 
856 static int __init acpi_pci_init(void)
857 {
858 	int ret;
859 
860 	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) {
861 		pr_info("ACPI FADT declares the system doesn't support MSI, so disable it\n");
862 		pci_no_msi();
863 	}
864 
865 	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
866 		pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
867 		pcie_no_aspm();
868 	}
869 
870 	ret = register_acpi_bus_type(&acpi_pci_bus);
871 	if (ret)
872 		return 0;
873 
874 	pci_set_platform_pm(&acpi_pci_platform_pm);
875 	acpi_pci_slot_init();
876 	acpiphp_init();
877 
878 	return 0;
879 }
880 arch_initcall(acpi_pci_init);
881