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