1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * (C) Copyright 2002-2004, 2007 Greg Kroah-Hartman <greg@kroah.com>
4  * (C) Copyright 2007 Novell Inc.
5  */
6 
7 #include <linux/pci.h>
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/device.h>
11 #include <linux/mempolicy.h>
12 #include <linux/string.h>
13 #include <linux/slab.h>
14 #include <linux/sched.h>
15 #include <linux/sched/isolation.h>
16 #include <linux/cpu.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/suspend.h>
19 #include <linux/kexec.h>
20 #include <linux/of_device.h>
21 #include <linux/acpi.h>
22 #include <linux/dma-map-ops.h>
23 #include "pci.h"
24 #include "pcie/portdrv.h"
25 
26 struct pci_dynid {
27 	struct list_head node;
28 	struct pci_device_id id;
29 };
30 
31 /**
32  * pci_add_dynid - add a new PCI device ID to this driver and re-probe devices
33  * @drv: target pci driver
34  * @vendor: PCI vendor ID
35  * @device: PCI device ID
36  * @subvendor: PCI subvendor ID
37  * @subdevice: PCI subdevice ID
38  * @class: PCI class
39  * @class_mask: PCI class mask
40  * @driver_data: private driver data
41  *
42  * Adds a new dynamic pci device ID to this driver and causes the
43  * driver to probe for all devices again.  @drv must have been
44  * registered prior to calling this function.
45  *
46  * CONTEXT:
47  * Does GFP_KERNEL allocation.
48  *
49  * RETURNS:
50  * 0 on success, -errno on failure.
51  */
pci_add_dynid(struct pci_driver * drv,unsigned int vendor,unsigned int device,unsigned int subvendor,unsigned int subdevice,unsigned int class,unsigned int class_mask,unsigned long driver_data)52 int pci_add_dynid(struct pci_driver *drv,
53 		  unsigned int vendor, unsigned int device,
54 		  unsigned int subvendor, unsigned int subdevice,
55 		  unsigned int class, unsigned int class_mask,
56 		  unsigned long driver_data)
57 {
58 	struct pci_dynid *dynid;
59 
60 	dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
61 	if (!dynid)
62 		return -ENOMEM;
63 
64 	dynid->id.vendor = vendor;
65 	dynid->id.device = device;
66 	dynid->id.subvendor = subvendor;
67 	dynid->id.subdevice = subdevice;
68 	dynid->id.class = class;
69 	dynid->id.class_mask = class_mask;
70 	dynid->id.driver_data = driver_data;
71 
72 	spin_lock(&drv->dynids.lock);
73 	list_add_tail(&dynid->node, &drv->dynids.list);
74 	spin_unlock(&drv->dynids.lock);
75 
76 	return driver_attach(&drv->driver);
77 }
78 EXPORT_SYMBOL_GPL(pci_add_dynid);
79 
pci_free_dynids(struct pci_driver * drv)80 static void pci_free_dynids(struct pci_driver *drv)
81 {
82 	struct pci_dynid *dynid, *n;
83 
84 	spin_lock(&drv->dynids.lock);
85 	list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
86 		list_del(&dynid->node);
87 		kfree(dynid);
88 	}
89 	spin_unlock(&drv->dynids.lock);
90 }
91 
92 /**
93  * store_new_id - sysfs frontend to pci_add_dynid()
94  * @driver: target device driver
95  * @buf: buffer for scanning device ID data
96  * @count: input size
97  *
98  * Allow PCI IDs to be added to an existing driver via sysfs.
99  */
new_id_store(struct device_driver * driver,const char * buf,size_t count)100 static ssize_t new_id_store(struct device_driver *driver, const char *buf,
101 			    size_t count)
102 {
103 	struct pci_driver *pdrv = to_pci_driver(driver);
104 	const struct pci_device_id *ids = pdrv->id_table;
105 	u32 vendor, device, subvendor = PCI_ANY_ID,
106 		subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
107 	unsigned long driver_data = 0;
108 	int fields = 0;
109 	int retval = 0;
110 
111 	fields = sscanf(buf, "%x %x %x %x %x %x %lx",
112 			&vendor, &device, &subvendor, &subdevice,
113 			&class, &class_mask, &driver_data);
114 	if (fields < 2)
115 		return -EINVAL;
116 
117 	if (fields != 7) {
118 		struct pci_dev *pdev = kzalloc(sizeof(*pdev), GFP_KERNEL);
119 		if (!pdev)
120 			return -ENOMEM;
121 
122 		pdev->vendor = vendor;
123 		pdev->device = device;
124 		pdev->subsystem_vendor = subvendor;
125 		pdev->subsystem_device = subdevice;
126 		pdev->class = class;
127 
128 		if (pci_match_id(pdrv->id_table, pdev))
129 			retval = -EEXIST;
130 
131 		kfree(pdev);
132 
133 		if (retval)
134 			return retval;
135 	}
136 
137 	/* Only accept driver_data values that match an existing id_table
138 	   entry */
139 	if (ids) {
140 		retval = -EINVAL;
141 		while (ids->vendor || ids->subvendor || ids->class_mask) {
142 			if (driver_data == ids->driver_data) {
143 				retval = 0;
144 				break;
145 			}
146 			ids++;
147 		}
148 		if (retval)	/* No match */
149 			return retval;
150 	}
151 
152 	retval = pci_add_dynid(pdrv, vendor, device, subvendor, subdevice,
153 			       class, class_mask, driver_data);
154 	if (retval)
155 		return retval;
156 	return count;
157 }
158 static DRIVER_ATTR_WO(new_id);
159 
160 /**
161  * store_remove_id - remove a PCI device ID from this driver
162  * @driver: target device driver
163  * @buf: buffer for scanning device ID data
164  * @count: input size
165  *
166  * Removes a dynamic pci device ID to this driver.
167  */
remove_id_store(struct device_driver * driver,const char * buf,size_t count)168 static ssize_t remove_id_store(struct device_driver *driver, const char *buf,
169 			       size_t count)
170 {
171 	struct pci_dynid *dynid, *n;
172 	struct pci_driver *pdrv = to_pci_driver(driver);
173 	u32 vendor, device, subvendor = PCI_ANY_ID,
174 		subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
175 	int fields = 0;
176 	size_t retval = -ENODEV;
177 
178 	fields = sscanf(buf, "%x %x %x %x %x %x",
179 			&vendor, &device, &subvendor, &subdevice,
180 			&class, &class_mask);
181 	if (fields < 2)
182 		return -EINVAL;
183 
184 	spin_lock(&pdrv->dynids.lock);
185 	list_for_each_entry_safe(dynid, n, &pdrv->dynids.list, node) {
186 		struct pci_device_id *id = &dynid->id;
187 		if ((id->vendor == vendor) &&
188 		    (id->device == device) &&
189 		    (subvendor == PCI_ANY_ID || id->subvendor == subvendor) &&
190 		    (subdevice == PCI_ANY_ID || id->subdevice == subdevice) &&
191 		    !((id->class ^ class) & class_mask)) {
192 			list_del(&dynid->node);
193 			kfree(dynid);
194 			retval = count;
195 			break;
196 		}
197 	}
198 	spin_unlock(&pdrv->dynids.lock);
199 
200 	return retval;
201 }
202 static DRIVER_ATTR_WO(remove_id);
203 
204 static struct attribute *pci_drv_attrs[] = {
205 	&driver_attr_new_id.attr,
206 	&driver_attr_remove_id.attr,
207 	NULL,
208 };
209 ATTRIBUTE_GROUPS(pci_drv);
210 
211 /**
212  * pci_match_id - See if a pci device matches a given pci_id table
213  * @ids: array of PCI device id structures to search in
214  * @dev: the PCI device structure to match against.
215  *
216  * Used by a driver to check whether a PCI device present in the
217  * system is in its list of supported devices.  Returns the matching
218  * pci_device_id structure or %NULL if there is no match.
219  *
220  * Deprecated, don't use this as it will not catch any dynamic ids
221  * that a driver might want to check for.
222  */
pci_match_id(const struct pci_device_id * ids,struct pci_dev * dev)223 const struct pci_device_id *pci_match_id(const struct pci_device_id *ids,
224 					 struct pci_dev *dev)
225 {
226 	if (ids) {
227 		while (ids->vendor || ids->subvendor || ids->class_mask) {
228 			if (pci_match_one_device(ids, dev))
229 				return ids;
230 			ids++;
231 		}
232 	}
233 	return NULL;
234 }
235 EXPORT_SYMBOL(pci_match_id);
236 
237 static const struct pci_device_id pci_device_id_any = {
238 	.vendor = PCI_ANY_ID,
239 	.device = PCI_ANY_ID,
240 	.subvendor = PCI_ANY_ID,
241 	.subdevice = PCI_ANY_ID,
242 };
243 
244 /**
245  * pci_match_device - Tell if a PCI device structure has a matching PCI device id structure
246  * @drv: the PCI driver to match against
247  * @dev: the PCI device structure to match against
248  *
249  * Used by a driver to check whether a PCI device present in the
250  * system is in its list of supported devices.  Returns the matching
251  * pci_device_id structure or %NULL if there is no match.
252  */
pci_match_device(struct pci_driver * drv,struct pci_dev * dev)253 static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
254 						    struct pci_dev *dev)
255 {
256 	struct pci_dynid *dynid;
257 	const struct pci_device_id *found_id = NULL;
258 
259 	/* When driver_override is set, only bind to the matching driver */
260 	if (dev->driver_override && strcmp(dev->driver_override, drv->name))
261 		return NULL;
262 
263 	/* Look at the dynamic ids first, before the static ones */
264 	spin_lock(&drv->dynids.lock);
265 	list_for_each_entry(dynid, &drv->dynids.list, node) {
266 		if (pci_match_one_device(&dynid->id, dev)) {
267 			found_id = &dynid->id;
268 			break;
269 		}
270 	}
271 	spin_unlock(&drv->dynids.lock);
272 
273 	if (!found_id)
274 		found_id = pci_match_id(drv->id_table, dev);
275 
276 	/* driver_override will always match, send a dummy id */
277 	if (!found_id && dev->driver_override)
278 		found_id = &pci_device_id_any;
279 
280 	return found_id;
281 }
282 
283 struct drv_dev_and_id {
284 	struct pci_driver *drv;
285 	struct pci_dev *dev;
286 	const struct pci_device_id *id;
287 };
288 
local_pci_probe(void * _ddi)289 static long local_pci_probe(void *_ddi)
290 {
291 	struct drv_dev_and_id *ddi = _ddi;
292 	struct pci_dev *pci_dev = ddi->dev;
293 	struct pci_driver *pci_drv = ddi->drv;
294 	struct device *dev = &pci_dev->dev;
295 	int rc;
296 
297 	/*
298 	 * Unbound PCI devices are always put in D0, regardless of
299 	 * runtime PM status.  During probe, the device is set to
300 	 * active and the usage count is incremented.  If the driver
301 	 * supports runtime PM, it should call pm_runtime_put_noidle(),
302 	 * or any other runtime PM helper function decrementing the usage
303 	 * count, in its probe routine and pm_runtime_get_noresume() in
304 	 * its remove routine.
305 	 */
306 	pm_runtime_get_sync(dev);
307 	pci_dev->driver = pci_drv;
308 	rc = pci_drv->probe(pci_dev, ddi->id);
309 	if (!rc)
310 		return rc;
311 	if (rc < 0) {
312 		pci_dev->driver = NULL;
313 		pm_runtime_put_sync(dev);
314 		return rc;
315 	}
316 	/*
317 	 * Probe function should return < 0 for failure, 0 for success
318 	 * Treat values > 0 as success, but warn.
319 	 */
320 	pci_warn(pci_dev, "Driver probe function unexpectedly returned %d\n",
321 		 rc);
322 	return 0;
323 }
324 
pci_physfn_is_probed(struct pci_dev * dev)325 static bool pci_physfn_is_probed(struct pci_dev *dev)
326 {
327 #ifdef CONFIG_PCI_IOV
328 	return dev->is_virtfn && dev->physfn->is_probed;
329 #else
330 	return false;
331 #endif
332 }
333 
pci_call_probe(struct pci_driver * drv,struct pci_dev * dev,const struct pci_device_id * id)334 static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
335 			  const struct pci_device_id *id)
336 {
337 	int error, node, cpu;
338 	int hk_flags = HK_FLAG_DOMAIN | HK_FLAG_WQ;
339 	struct drv_dev_and_id ddi = { drv, dev, id };
340 
341 	/*
342 	 * Execute driver initialization on node where the device is
343 	 * attached.  This way the driver likely allocates its local memory
344 	 * on the right node.
345 	 */
346 	node = dev_to_node(&dev->dev);
347 	dev->is_probed = 1;
348 
349 	cpu_hotplug_disable();
350 
351 	/*
352 	 * Prevent nesting work_on_cpu() for the case where a Virtual Function
353 	 * device is probed from work_on_cpu() of the Physical device.
354 	 */
355 	if (node < 0 || node >= MAX_NUMNODES || !node_online(node) ||
356 	    pci_physfn_is_probed(dev))
357 		cpu = nr_cpu_ids;
358 	else
359 		cpu = cpumask_any_and(cpumask_of_node(node),
360 				      housekeeping_cpumask(hk_flags));
361 
362 	if (cpu < nr_cpu_ids)
363 		error = work_on_cpu(cpu, local_pci_probe, &ddi);
364 	else
365 		error = local_pci_probe(&ddi);
366 
367 	dev->is_probed = 0;
368 	cpu_hotplug_enable();
369 	return error;
370 }
371 
372 /**
373  * __pci_device_probe - check if a driver wants to claim a specific PCI device
374  * @drv: driver to call to check if it wants the PCI device
375  * @pci_dev: PCI device being probed
376  *
377  * returns 0 on success, else error.
378  * side-effect: pci_dev->driver is set to drv when drv claims pci_dev.
379  */
__pci_device_probe(struct pci_driver * drv,struct pci_dev * pci_dev)380 static int __pci_device_probe(struct pci_driver *drv, struct pci_dev *pci_dev)
381 {
382 	const struct pci_device_id *id;
383 	int error = 0;
384 
385 	if (!pci_dev->driver && drv->probe) {
386 		error = -ENODEV;
387 
388 		id = pci_match_device(drv, pci_dev);
389 		if (id)
390 			error = pci_call_probe(drv, pci_dev, id);
391 	}
392 	return error;
393 }
394 
pcibios_alloc_irq(struct pci_dev * dev)395 int __weak pcibios_alloc_irq(struct pci_dev *dev)
396 {
397 	return 0;
398 }
399 
pcibios_free_irq(struct pci_dev * dev)400 void __weak pcibios_free_irq(struct pci_dev *dev)
401 {
402 }
403 
404 #ifdef CONFIG_PCI_IOV
pci_device_can_probe(struct pci_dev * pdev)405 static inline bool pci_device_can_probe(struct pci_dev *pdev)
406 {
407 	return (!pdev->is_virtfn || pdev->physfn->sriov->drivers_autoprobe ||
408 		pdev->driver_override);
409 }
410 #else
pci_device_can_probe(struct pci_dev * pdev)411 static inline bool pci_device_can_probe(struct pci_dev *pdev)
412 {
413 	return true;
414 }
415 #endif
416 
pci_device_probe(struct device * dev)417 static int pci_device_probe(struct device *dev)
418 {
419 	int error;
420 	struct pci_dev *pci_dev = to_pci_dev(dev);
421 	struct pci_driver *drv = to_pci_driver(dev->driver);
422 
423 	if (!pci_device_can_probe(pci_dev))
424 		return -ENODEV;
425 
426 	pci_assign_irq(pci_dev);
427 
428 	error = pcibios_alloc_irq(pci_dev);
429 	if (error < 0)
430 		return error;
431 
432 	pci_dev_get(pci_dev);
433 	error = __pci_device_probe(drv, pci_dev);
434 	if (error) {
435 		pcibios_free_irq(pci_dev);
436 		pci_dev_put(pci_dev);
437 	}
438 
439 	return error;
440 }
441 
pci_device_remove(struct device * dev)442 static int pci_device_remove(struct device *dev)
443 {
444 	struct pci_dev *pci_dev = to_pci_dev(dev);
445 	struct pci_driver *drv = pci_dev->driver;
446 
447 	if (drv) {
448 		if (drv->remove) {
449 			pm_runtime_get_sync(dev);
450 			drv->remove(pci_dev);
451 			pm_runtime_put_noidle(dev);
452 		}
453 		pcibios_free_irq(pci_dev);
454 		pci_dev->driver = NULL;
455 		pci_iov_remove(pci_dev);
456 	}
457 
458 	/* Undo the runtime PM settings in local_pci_probe() */
459 	pm_runtime_put_sync(dev);
460 
461 	/*
462 	 * If the device is still on, set the power state as "unknown",
463 	 * since it might change by the next time we load the driver.
464 	 */
465 	if (pci_dev->current_state == PCI_D0)
466 		pci_dev->current_state = PCI_UNKNOWN;
467 
468 	/*
469 	 * We would love to complain here if pci_dev->is_enabled is set, that
470 	 * the driver should have called pci_disable_device(), but the
471 	 * unfortunate fact is there are too many odd BIOS and bridge setups
472 	 * that don't like drivers doing that all of the time.
473 	 * Oh well, we can dream of sane hardware when we sleep, no matter how
474 	 * horrible the crap we have to deal with is when we are awake...
475 	 */
476 
477 	pci_dev_put(pci_dev);
478 	return 0;
479 }
480 
pci_device_shutdown(struct device * dev)481 static void pci_device_shutdown(struct device *dev)
482 {
483 	struct pci_dev *pci_dev = to_pci_dev(dev);
484 	struct pci_driver *drv = pci_dev->driver;
485 
486 	pm_runtime_resume(dev);
487 
488 	if (drv && drv->shutdown)
489 		drv->shutdown(pci_dev);
490 
491 	/*
492 	 * If this is a kexec reboot, turn off Bus Master bit on the
493 	 * device to tell it to not continue to do DMA. Don't touch
494 	 * devices in D3cold or unknown states.
495 	 * If it is not a kexec reboot, firmware will hit the PCI
496 	 * devices with big hammer and stop their DMA any way.
497 	 */
498 	if (kexec_in_progress && (pci_dev->current_state <= PCI_D3hot))
499 		pci_clear_master(pci_dev);
500 }
501 
502 #ifdef CONFIG_PM
503 
504 /* Auxiliary functions used for system resume and run-time resume. */
505 
506 /**
507  * pci_restore_standard_config - restore standard config registers of PCI device
508  * @pci_dev: PCI device to handle
509  */
pci_restore_standard_config(struct pci_dev * pci_dev)510 static int pci_restore_standard_config(struct pci_dev *pci_dev)
511 {
512 	pci_update_current_state(pci_dev, PCI_UNKNOWN);
513 
514 	if (pci_dev->current_state != PCI_D0) {
515 		int error = pci_set_power_state(pci_dev, PCI_D0);
516 		if (error)
517 			return error;
518 	}
519 
520 	pci_restore_state(pci_dev);
521 	pci_pme_restore(pci_dev);
522 	return 0;
523 }
524 
pci_pm_default_resume(struct pci_dev * pci_dev)525 static void pci_pm_default_resume(struct pci_dev *pci_dev)
526 {
527 	pci_fixup_device(pci_fixup_resume, pci_dev);
528 	pci_enable_wake(pci_dev, PCI_D0, false);
529 }
530 
531 #endif
532 
533 #ifdef CONFIG_PM_SLEEP
534 
pci_pm_default_resume_early(struct pci_dev * pci_dev)535 static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
536 {
537 	pci_power_up(pci_dev);
538 	pci_update_current_state(pci_dev, PCI_D0);
539 	pci_restore_state(pci_dev);
540 	pci_pme_restore(pci_dev);
541 }
542 
543 /*
544  * Default "suspend" method for devices that have no driver provided suspend,
545  * or not even a driver at all (second part).
546  */
pci_pm_set_unknown_state(struct pci_dev * pci_dev)547 static void pci_pm_set_unknown_state(struct pci_dev *pci_dev)
548 {
549 	/*
550 	 * mark its power state as "unknown", since we don't know if
551 	 * e.g. the BIOS will change its device state when we suspend.
552 	 */
553 	if (pci_dev->current_state == PCI_D0)
554 		pci_dev->current_state = PCI_UNKNOWN;
555 }
556 
557 /*
558  * Default "resume" method for devices that have no driver provided resume,
559  * or not even a driver at all (second part).
560  */
pci_pm_reenable_device(struct pci_dev * pci_dev)561 static int pci_pm_reenable_device(struct pci_dev *pci_dev)
562 {
563 	int retval;
564 
565 	/* if the device was enabled before suspend, reenable */
566 	retval = pci_reenable_device(pci_dev);
567 	/*
568 	 * if the device was busmaster before the suspend, make it busmaster
569 	 * again
570 	 */
571 	if (pci_dev->is_busmaster)
572 		pci_set_master(pci_dev);
573 
574 	return retval;
575 }
576 
pci_legacy_suspend(struct device * dev,pm_message_t state)577 static int pci_legacy_suspend(struct device *dev, pm_message_t state)
578 {
579 	struct pci_dev *pci_dev = to_pci_dev(dev);
580 	struct pci_driver *drv = pci_dev->driver;
581 
582 	if (drv && drv->suspend) {
583 		pci_power_t prev = pci_dev->current_state;
584 		int error;
585 
586 		error = drv->suspend(pci_dev, state);
587 		suspend_report_result(drv->suspend, error);
588 		if (error)
589 			return error;
590 
591 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
592 		    && pci_dev->current_state != PCI_UNKNOWN) {
593 			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
594 				      "PCI PM: Device state not saved by %pS\n",
595 				      drv->suspend);
596 		}
597 	}
598 
599 	pci_fixup_device(pci_fixup_suspend, pci_dev);
600 
601 	return 0;
602 }
603 
pci_legacy_suspend_late(struct device * dev,pm_message_t state)604 static int pci_legacy_suspend_late(struct device *dev, pm_message_t state)
605 {
606 	struct pci_dev *pci_dev = to_pci_dev(dev);
607 
608 	if (!pci_dev->state_saved)
609 		pci_save_state(pci_dev);
610 
611 	pci_pm_set_unknown_state(pci_dev);
612 
613 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
614 
615 	return 0;
616 }
617 
pci_legacy_resume(struct device * dev)618 static int pci_legacy_resume(struct device *dev)
619 {
620 	struct pci_dev *pci_dev = to_pci_dev(dev);
621 	struct pci_driver *drv = pci_dev->driver;
622 
623 	pci_fixup_device(pci_fixup_resume, pci_dev);
624 
625 	return drv && drv->resume ?
626 			drv->resume(pci_dev) : pci_pm_reenable_device(pci_dev);
627 }
628 
629 /* Auxiliary functions used by the new power management framework */
630 
pci_pm_default_suspend(struct pci_dev * pci_dev)631 static void pci_pm_default_suspend(struct pci_dev *pci_dev)
632 {
633 	/* Disable non-bridge devices without PM support */
634 	if (!pci_has_subordinate(pci_dev))
635 		pci_disable_enabled_device(pci_dev);
636 }
637 
pci_has_legacy_pm_support(struct pci_dev * pci_dev)638 static bool pci_has_legacy_pm_support(struct pci_dev *pci_dev)
639 {
640 	struct pci_driver *drv = pci_dev->driver;
641 	bool ret = drv && (drv->suspend || drv->resume);
642 
643 	/*
644 	 * Legacy PM support is used by default, so warn if the new framework is
645 	 * supported as well.  Drivers are supposed to support either the
646 	 * former, or the latter, but not both at the same time.
647 	 */
648 	pci_WARN(pci_dev, ret && drv->driver.pm, "device %04x:%04x\n",
649 		 pci_dev->vendor, pci_dev->device);
650 
651 	return ret;
652 }
653 
654 /* New power management framework */
655 
pci_pm_prepare(struct device * dev)656 static int pci_pm_prepare(struct device *dev)
657 {
658 	struct pci_dev *pci_dev = to_pci_dev(dev);
659 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
660 
661 	if (pm && pm->prepare) {
662 		int error = pm->prepare(dev);
663 		if (error < 0)
664 			return error;
665 
666 		if (!error && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
667 			return 0;
668 	}
669 	if (pci_dev_need_resume(pci_dev))
670 		return 0;
671 
672 	/*
673 	 * The PME setting needs to be adjusted here in case the direct-complete
674 	 * optimization is used with respect to this device.
675 	 */
676 	pci_dev_adjust_pme(pci_dev);
677 	return 1;
678 }
679 
pci_pm_complete(struct device * dev)680 static void pci_pm_complete(struct device *dev)
681 {
682 	struct pci_dev *pci_dev = to_pci_dev(dev);
683 
684 	pci_dev_complete_resume(pci_dev);
685 	pm_generic_complete(dev);
686 
687 	/* Resume device if platform firmware has put it in reset-power-on */
688 	if (pm_runtime_suspended(dev) && pm_resume_via_firmware()) {
689 		pci_power_t pre_sleep_state = pci_dev->current_state;
690 
691 		pci_refresh_power_state(pci_dev);
692 		/*
693 		 * On platforms with ACPI this check may also trigger for
694 		 * devices sharing power resources if one of those power
695 		 * resources has been activated as a result of a change of the
696 		 * power state of another device sharing it.  However, in that
697 		 * case it is also better to resume the device, in general.
698 		 */
699 		if (pci_dev->current_state < pre_sleep_state)
700 			pm_request_resume(dev);
701 	}
702 }
703 
704 #else /* !CONFIG_PM_SLEEP */
705 
706 #define pci_pm_prepare	NULL
707 #define pci_pm_complete	NULL
708 
709 #endif /* !CONFIG_PM_SLEEP */
710 
711 #ifdef CONFIG_SUSPEND
pcie_pme_root_status_cleanup(struct pci_dev * pci_dev)712 static void pcie_pme_root_status_cleanup(struct pci_dev *pci_dev)
713 {
714 	/*
715 	 * Some BIOSes forget to clear Root PME Status bits after system
716 	 * wakeup, which breaks ACPI-based runtime wakeup on PCI Express.
717 	 * Clear those bits now just in case (shouldn't hurt).
718 	 */
719 	if (pci_is_pcie(pci_dev) &&
720 	    (pci_pcie_type(pci_dev) == PCI_EXP_TYPE_ROOT_PORT ||
721 	     pci_pcie_type(pci_dev) == PCI_EXP_TYPE_RC_EC))
722 		pcie_clear_root_pme_status(pci_dev);
723 }
724 
pci_pm_suspend(struct device * dev)725 static int pci_pm_suspend(struct device *dev)
726 {
727 	struct pci_dev *pci_dev = to_pci_dev(dev);
728 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
729 
730 	pci_dev->skip_bus_pm = false;
731 
732 	if (pci_has_legacy_pm_support(pci_dev))
733 		return pci_legacy_suspend(dev, PMSG_SUSPEND);
734 
735 	if (!pm) {
736 		pci_pm_default_suspend(pci_dev);
737 		return 0;
738 	}
739 
740 	/*
741 	 * PCI devices suspended at run time may need to be resumed at this
742 	 * point, because in general it may be necessary to reconfigure them for
743 	 * system suspend.  Namely, if the device is expected to wake up the
744 	 * system from the sleep state, it may have to be reconfigured for this
745 	 * purpose, or if the device is not expected to wake up the system from
746 	 * the sleep state, it should be prevented from signaling wakeup events
747 	 * going forward.
748 	 *
749 	 * Also if the driver of the device does not indicate that its system
750 	 * suspend callbacks can cope with runtime-suspended devices, it is
751 	 * better to resume the device from runtime suspend here.
752 	 */
753 	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
754 	    pci_dev_need_resume(pci_dev)) {
755 		pm_runtime_resume(dev);
756 		pci_dev->state_saved = false;
757 	} else {
758 		pci_dev_adjust_pme(pci_dev);
759 	}
760 
761 	if (pm->suspend) {
762 		pci_power_t prev = pci_dev->current_state;
763 		int error;
764 
765 		error = pm->suspend(dev);
766 		suspend_report_result(pm->suspend, error);
767 		if (error)
768 			return error;
769 
770 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
771 		    && pci_dev->current_state != PCI_UNKNOWN) {
772 			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
773 				      "PCI PM: State of device not saved by %pS\n",
774 				      pm->suspend);
775 		}
776 	}
777 
778 	return 0;
779 }
780 
pci_pm_suspend_late(struct device * dev)781 static int pci_pm_suspend_late(struct device *dev)
782 {
783 	if (dev_pm_skip_suspend(dev))
784 		return 0;
785 
786 	pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));
787 
788 	return pm_generic_suspend_late(dev);
789 }
790 
pci_pm_suspend_noirq(struct device * dev)791 static int pci_pm_suspend_noirq(struct device *dev)
792 {
793 	struct pci_dev *pci_dev = to_pci_dev(dev);
794 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
795 
796 	if (dev_pm_skip_suspend(dev))
797 		return 0;
798 
799 	if (pci_has_legacy_pm_support(pci_dev))
800 		return pci_legacy_suspend_late(dev, PMSG_SUSPEND);
801 
802 	if (!pm) {
803 		pci_save_state(pci_dev);
804 		goto Fixup;
805 	}
806 
807 	if (pm->suspend_noirq) {
808 		pci_power_t prev = pci_dev->current_state;
809 		int error;
810 
811 		error = pm->suspend_noirq(dev);
812 		suspend_report_result(pm->suspend_noirq, error);
813 		if (error)
814 			return error;
815 
816 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
817 		    && pci_dev->current_state != PCI_UNKNOWN) {
818 			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
819 				      "PCI PM: State of device not saved by %pS\n",
820 				      pm->suspend_noirq);
821 			goto Fixup;
822 		}
823 	}
824 
825 	if (pci_dev->skip_bus_pm) {
826 		/*
827 		 * Either the device is a bridge with a child in D0 below it, or
828 		 * the function is running for the second time in a row without
829 		 * going through full resume, which is possible only during
830 		 * suspend-to-idle in a spurious wakeup case.  The device should
831 		 * be in D0 at this point, but if it is a bridge, it may be
832 		 * necessary to save its state.
833 		 */
834 		if (!pci_dev->state_saved)
835 			pci_save_state(pci_dev);
836 	} else if (!pci_dev->state_saved) {
837 		pci_save_state(pci_dev);
838 		if (pci_power_manageable(pci_dev))
839 			pci_prepare_to_sleep(pci_dev);
840 	}
841 
842 	pci_dbg(pci_dev, "PCI PM: Suspend power state: %s\n",
843 		pci_power_name(pci_dev->current_state));
844 
845 	if (pci_dev->current_state == PCI_D0) {
846 		pci_dev->skip_bus_pm = true;
847 		/*
848 		 * Per PCI PM r1.2, table 6-1, a bridge must be in D0 if any
849 		 * downstream device is in D0, so avoid changing the power state
850 		 * of the parent bridge by setting the skip_bus_pm flag for it.
851 		 */
852 		if (pci_dev->bus->self)
853 			pci_dev->bus->self->skip_bus_pm = true;
854 	}
855 
856 	if (pci_dev->skip_bus_pm && pm_suspend_no_platform()) {
857 		pci_dbg(pci_dev, "PCI PM: Skipped\n");
858 		goto Fixup;
859 	}
860 
861 	pci_pm_set_unknown_state(pci_dev);
862 
863 	/*
864 	 * Some BIOSes from ASUS have a bug: If a USB EHCI host controller's
865 	 * PCI COMMAND register isn't 0, the BIOS assumes that the controller
866 	 * hasn't been quiesced and tries to turn it off.  If the controller
867 	 * is already in D3, this can hang or cause memory corruption.
868 	 *
869 	 * Since the value of the COMMAND register doesn't matter once the
870 	 * device has been suspended, we can safely set it to 0 here.
871 	 */
872 	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
873 		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
874 
875 Fixup:
876 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
877 
878 	/*
879 	 * If the target system sleep state is suspend-to-idle, it is sufficient
880 	 * to check whether or not the device's wakeup settings are good for
881 	 * runtime PM.  Otherwise, the pm_resume_via_firmware() check will cause
882 	 * pci_pm_complete() to take care of fixing up the device's state
883 	 * anyway, if need be.
884 	 */
885 	if (device_can_wakeup(dev) && !device_may_wakeup(dev))
886 		dev->power.may_skip_resume = false;
887 
888 	return 0;
889 }
890 
pci_pm_resume_noirq(struct device * dev)891 static int pci_pm_resume_noirq(struct device *dev)
892 {
893 	struct pci_dev *pci_dev = to_pci_dev(dev);
894 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
895 	pci_power_t prev_state = pci_dev->current_state;
896 	bool skip_bus_pm = pci_dev->skip_bus_pm;
897 
898 	if (dev_pm_skip_resume(dev))
899 		return 0;
900 
901 	/*
902 	 * In the suspend-to-idle case, devices left in D0 during suspend will
903 	 * stay in D0, so it is not necessary to restore or update their
904 	 * configuration here and attempting to put them into D0 again is
905 	 * pointless, so avoid doing that.
906 	 */
907 	if (!(skip_bus_pm && pm_suspend_no_platform()))
908 		pci_pm_default_resume_early(pci_dev);
909 
910 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
911 	pcie_pme_root_status_cleanup(pci_dev);
912 
913 	if (!skip_bus_pm && prev_state == PCI_D3cold)
914 		pci_bridge_wait_for_secondary_bus(pci_dev);
915 
916 	if (pci_has_legacy_pm_support(pci_dev))
917 		return 0;
918 
919 	if (pm && pm->resume_noirq)
920 		return pm->resume_noirq(dev);
921 
922 	return 0;
923 }
924 
pci_pm_resume_early(struct device * dev)925 static int pci_pm_resume_early(struct device *dev)
926 {
927 	if (dev_pm_skip_resume(dev))
928 		return 0;
929 
930 	return pm_generic_resume_early(dev);
931 }
932 
pci_pm_resume(struct device * dev)933 static int pci_pm_resume(struct device *dev)
934 {
935 	struct pci_dev *pci_dev = to_pci_dev(dev);
936 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
937 
938 	/*
939 	 * This is necessary for the suspend error path in which resume is
940 	 * called without restoring the standard config registers of the device.
941 	 */
942 	if (pci_dev->state_saved)
943 		pci_restore_standard_config(pci_dev);
944 
945 	if (pci_has_legacy_pm_support(pci_dev))
946 		return pci_legacy_resume(dev);
947 
948 	pci_pm_default_resume(pci_dev);
949 
950 	if (pm) {
951 		if (pm->resume)
952 			return pm->resume(dev);
953 	} else {
954 		pci_pm_reenable_device(pci_dev);
955 	}
956 
957 	return 0;
958 }
959 
960 #else /* !CONFIG_SUSPEND */
961 
962 #define pci_pm_suspend		NULL
963 #define pci_pm_suspend_late	NULL
964 #define pci_pm_suspend_noirq	NULL
965 #define pci_pm_resume		NULL
966 #define pci_pm_resume_early	NULL
967 #define pci_pm_resume_noirq	NULL
968 
969 #endif /* !CONFIG_SUSPEND */
970 
971 #ifdef CONFIG_HIBERNATE_CALLBACKS
972 
pci_pm_freeze(struct device * dev)973 static int pci_pm_freeze(struct device *dev)
974 {
975 	struct pci_dev *pci_dev = to_pci_dev(dev);
976 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
977 
978 	if (pci_has_legacy_pm_support(pci_dev))
979 		return pci_legacy_suspend(dev, PMSG_FREEZE);
980 
981 	if (!pm) {
982 		pci_pm_default_suspend(pci_dev);
983 		return 0;
984 	}
985 
986 	/*
987 	 * Resume all runtime-suspended devices before creating a snapshot
988 	 * image of system memory, because the restore kernel generally cannot
989 	 * be expected to always handle them consistently and they need to be
990 	 * put into the runtime-active metastate during system resume anyway,
991 	 * so it is better to ensure that the state saved in the image will be
992 	 * always consistent with that.
993 	 */
994 	pm_runtime_resume(dev);
995 	pci_dev->state_saved = false;
996 
997 	if (pm->freeze) {
998 		int error;
999 
1000 		error = pm->freeze(dev);
1001 		suspend_report_result(pm->freeze, error);
1002 		if (error)
1003 			return error;
1004 	}
1005 
1006 	return 0;
1007 }
1008 
pci_pm_freeze_noirq(struct device * dev)1009 static int pci_pm_freeze_noirq(struct device *dev)
1010 {
1011 	struct pci_dev *pci_dev = to_pci_dev(dev);
1012 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1013 
1014 	if (pci_has_legacy_pm_support(pci_dev))
1015 		return pci_legacy_suspend_late(dev, PMSG_FREEZE);
1016 
1017 	if (pm && pm->freeze_noirq) {
1018 		int error;
1019 
1020 		error = pm->freeze_noirq(dev);
1021 		suspend_report_result(pm->freeze_noirq, error);
1022 		if (error)
1023 			return error;
1024 	}
1025 
1026 	if (!pci_dev->state_saved)
1027 		pci_save_state(pci_dev);
1028 
1029 	pci_pm_set_unknown_state(pci_dev);
1030 
1031 	return 0;
1032 }
1033 
pci_pm_thaw_noirq(struct device * dev)1034 static int pci_pm_thaw_noirq(struct device *dev)
1035 {
1036 	struct pci_dev *pci_dev = to_pci_dev(dev);
1037 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1038 
1039 	/*
1040 	 * The pm->thaw_noirq() callback assumes the device has been
1041 	 * returned to D0 and its config state has been restored.
1042 	 *
1043 	 * In addition, pci_restore_state() restores MSI-X state in MMIO
1044 	 * space, which requires the device to be in D0, so return it to D0
1045 	 * in case the driver's "freeze" callbacks put it into a low-power
1046 	 * state.
1047 	 */
1048 	pci_set_power_state(pci_dev, PCI_D0);
1049 	pci_restore_state(pci_dev);
1050 
1051 	if (pci_has_legacy_pm_support(pci_dev))
1052 		return 0;
1053 
1054 	if (pm && pm->thaw_noirq)
1055 		return pm->thaw_noirq(dev);
1056 
1057 	return 0;
1058 }
1059 
pci_pm_thaw(struct device * dev)1060 static int pci_pm_thaw(struct device *dev)
1061 {
1062 	struct pci_dev *pci_dev = to_pci_dev(dev);
1063 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1064 	int error = 0;
1065 
1066 	if (pci_has_legacy_pm_support(pci_dev))
1067 		return pci_legacy_resume(dev);
1068 
1069 	if (pm) {
1070 		if (pm->thaw)
1071 			error = pm->thaw(dev);
1072 	} else {
1073 		pci_pm_reenable_device(pci_dev);
1074 	}
1075 
1076 	pci_dev->state_saved = false;
1077 
1078 	return error;
1079 }
1080 
pci_pm_poweroff(struct device * dev)1081 static int pci_pm_poweroff(struct device *dev)
1082 {
1083 	struct pci_dev *pci_dev = to_pci_dev(dev);
1084 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1085 
1086 	if (pci_has_legacy_pm_support(pci_dev))
1087 		return pci_legacy_suspend(dev, PMSG_HIBERNATE);
1088 
1089 	if (!pm) {
1090 		pci_pm_default_suspend(pci_dev);
1091 		return 0;
1092 	}
1093 
1094 	/* The reason to do that is the same as in pci_pm_suspend(). */
1095 	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1096 	    pci_dev_need_resume(pci_dev)) {
1097 		pm_runtime_resume(dev);
1098 		pci_dev->state_saved = false;
1099 	} else {
1100 		pci_dev_adjust_pme(pci_dev);
1101 	}
1102 
1103 	if (pm->poweroff) {
1104 		int error;
1105 
1106 		error = pm->poweroff(dev);
1107 		suspend_report_result(pm->poweroff, error);
1108 		if (error)
1109 			return error;
1110 	}
1111 
1112 	return 0;
1113 }
1114 
pci_pm_poweroff_late(struct device * dev)1115 static int pci_pm_poweroff_late(struct device *dev)
1116 {
1117 	if (dev_pm_skip_suspend(dev))
1118 		return 0;
1119 
1120 	pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));
1121 
1122 	return pm_generic_poweroff_late(dev);
1123 }
1124 
pci_pm_poweroff_noirq(struct device * dev)1125 static int pci_pm_poweroff_noirq(struct device *dev)
1126 {
1127 	struct pci_dev *pci_dev = to_pci_dev(dev);
1128 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1129 
1130 	if (dev_pm_skip_suspend(dev))
1131 		return 0;
1132 
1133 	if (pci_has_legacy_pm_support(pci_dev))
1134 		return pci_legacy_suspend_late(dev, PMSG_HIBERNATE);
1135 
1136 	if (!pm) {
1137 		pci_fixup_device(pci_fixup_suspend_late, pci_dev);
1138 		return 0;
1139 	}
1140 
1141 	if (pm->poweroff_noirq) {
1142 		int error;
1143 
1144 		error = pm->poweroff_noirq(dev);
1145 		suspend_report_result(pm->poweroff_noirq, error);
1146 		if (error)
1147 			return error;
1148 	}
1149 
1150 	if (!pci_dev->state_saved && !pci_has_subordinate(pci_dev))
1151 		pci_prepare_to_sleep(pci_dev);
1152 
1153 	/*
1154 	 * The reason for doing this here is the same as for the analogous code
1155 	 * in pci_pm_suspend_noirq().
1156 	 */
1157 	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
1158 		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
1159 
1160 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
1161 
1162 	return 0;
1163 }
1164 
pci_pm_restore_noirq(struct device * dev)1165 static int pci_pm_restore_noirq(struct device *dev)
1166 {
1167 	struct pci_dev *pci_dev = to_pci_dev(dev);
1168 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1169 
1170 	pci_pm_default_resume_early(pci_dev);
1171 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
1172 
1173 	if (pci_has_legacy_pm_support(pci_dev))
1174 		return 0;
1175 
1176 	if (pm && pm->restore_noirq)
1177 		return pm->restore_noirq(dev);
1178 
1179 	return 0;
1180 }
1181 
pci_pm_restore(struct device * dev)1182 static int pci_pm_restore(struct device *dev)
1183 {
1184 	struct pci_dev *pci_dev = to_pci_dev(dev);
1185 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1186 
1187 	/*
1188 	 * This is necessary for the hibernation error path in which restore is
1189 	 * called without restoring the standard config registers of the device.
1190 	 */
1191 	if (pci_dev->state_saved)
1192 		pci_restore_standard_config(pci_dev);
1193 
1194 	if (pci_has_legacy_pm_support(pci_dev))
1195 		return pci_legacy_resume(dev);
1196 
1197 	pci_pm_default_resume(pci_dev);
1198 
1199 	if (pm) {
1200 		if (pm->restore)
1201 			return pm->restore(dev);
1202 	} else {
1203 		pci_pm_reenable_device(pci_dev);
1204 	}
1205 
1206 	return 0;
1207 }
1208 
1209 #else /* !CONFIG_HIBERNATE_CALLBACKS */
1210 
1211 #define pci_pm_freeze		NULL
1212 #define pci_pm_freeze_noirq	NULL
1213 #define pci_pm_thaw		NULL
1214 #define pci_pm_thaw_noirq	NULL
1215 #define pci_pm_poweroff		NULL
1216 #define pci_pm_poweroff_late	NULL
1217 #define pci_pm_poweroff_noirq	NULL
1218 #define pci_pm_restore		NULL
1219 #define pci_pm_restore_noirq	NULL
1220 
1221 #endif /* !CONFIG_HIBERNATE_CALLBACKS */
1222 
1223 #ifdef CONFIG_PM
1224 
pci_pm_runtime_suspend(struct device * dev)1225 static int pci_pm_runtime_suspend(struct device *dev)
1226 {
1227 	struct pci_dev *pci_dev = to_pci_dev(dev);
1228 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1229 	pci_power_t prev = pci_dev->current_state;
1230 	int error;
1231 
1232 	/*
1233 	 * If pci_dev->driver is not set (unbound), we leave the device in D0,
1234 	 * but it may go to D3cold when the bridge above it runtime suspends.
1235 	 * Save its config space in case that happens.
1236 	 */
1237 	if (!pci_dev->driver) {
1238 		pci_save_state(pci_dev);
1239 		return 0;
1240 	}
1241 
1242 	pci_dev->state_saved = false;
1243 	if (pm && pm->runtime_suspend) {
1244 		error = pm->runtime_suspend(dev);
1245 		/*
1246 		 * -EBUSY and -EAGAIN is used to request the runtime PM core
1247 		 * to schedule a new suspend, so log the event only with debug
1248 		 * log level.
1249 		 */
1250 		if (error == -EBUSY || error == -EAGAIN) {
1251 			pci_dbg(pci_dev, "can't suspend now (%ps returned %d)\n",
1252 				pm->runtime_suspend, error);
1253 			return error;
1254 		} else if (error) {
1255 			pci_err(pci_dev, "can't suspend (%ps returned %d)\n",
1256 				pm->runtime_suspend, error);
1257 			return error;
1258 		}
1259 	}
1260 
1261 	pci_fixup_device(pci_fixup_suspend, pci_dev);
1262 
1263 	if (pm && pm->runtime_suspend
1264 	    && !pci_dev->state_saved && pci_dev->current_state != PCI_D0
1265 	    && pci_dev->current_state != PCI_UNKNOWN) {
1266 		pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
1267 			      "PCI PM: State of device not saved by %pS\n",
1268 			      pm->runtime_suspend);
1269 		return 0;
1270 	}
1271 
1272 	if (!pci_dev->state_saved) {
1273 		pci_save_state(pci_dev);
1274 		pci_finish_runtime_suspend(pci_dev);
1275 	}
1276 
1277 	return 0;
1278 }
1279 
pci_pm_runtime_resume(struct device * dev)1280 static int pci_pm_runtime_resume(struct device *dev)
1281 {
1282 	struct pci_dev *pci_dev = to_pci_dev(dev);
1283 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1284 	pci_power_t prev_state = pci_dev->current_state;
1285 	int error = 0;
1286 
1287 	/*
1288 	 * Restoring config space is necessary even if the device is not bound
1289 	 * to a driver because although we left it in D0, it may have gone to
1290 	 * D3cold when the bridge above it runtime suspended.
1291 	 */
1292 	pci_restore_standard_config(pci_dev);
1293 
1294 	if (!pci_dev->driver)
1295 		return 0;
1296 
1297 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
1298 	pci_pm_default_resume(pci_dev);
1299 
1300 	if (prev_state == PCI_D3cold)
1301 		pci_bridge_wait_for_secondary_bus(pci_dev);
1302 
1303 	if (pm && pm->runtime_resume)
1304 		error = pm->runtime_resume(dev);
1305 
1306 	pci_dev->runtime_d3cold = false;
1307 
1308 	return error;
1309 }
1310 
pci_pm_runtime_idle(struct device * dev)1311 static int pci_pm_runtime_idle(struct device *dev)
1312 {
1313 	struct pci_dev *pci_dev = to_pci_dev(dev);
1314 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1315 
1316 	/*
1317 	 * If pci_dev->driver is not set (unbound), the device should
1318 	 * always remain in D0 regardless of the runtime PM status
1319 	 */
1320 	if (!pci_dev->driver)
1321 		return 0;
1322 
1323 	if (!pm)
1324 		return -ENOSYS;
1325 
1326 	if (pm->runtime_idle)
1327 		return pm->runtime_idle(dev);
1328 
1329 	return 0;
1330 }
1331 
1332 static const struct dev_pm_ops pci_dev_pm_ops = {
1333 	.prepare = pci_pm_prepare,
1334 	.complete = pci_pm_complete,
1335 	.suspend = pci_pm_suspend,
1336 	.suspend_late = pci_pm_suspend_late,
1337 	.resume = pci_pm_resume,
1338 	.resume_early = pci_pm_resume_early,
1339 	.freeze = pci_pm_freeze,
1340 	.thaw = pci_pm_thaw,
1341 	.poweroff = pci_pm_poweroff,
1342 	.poweroff_late = pci_pm_poweroff_late,
1343 	.restore = pci_pm_restore,
1344 	.suspend_noirq = pci_pm_suspend_noirq,
1345 	.resume_noirq = pci_pm_resume_noirq,
1346 	.freeze_noirq = pci_pm_freeze_noirq,
1347 	.thaw_noirq = pci_pm_thaw_noirq,
1348 	.poweroff_noirq = pci_pm_poweroff_noirq,
1349 	.restore_noirq = pci_pm_restore_noirq,
1350 	.runtime_suspend = pci_pm_runtime_suspend,
1351 	.runtime_resume = pci_pm_runtime_resume,
1352 	.runtime_idle = pci_pm_runtime_idle,
1353 };
1354 
1355 #define PCI_PM_OPS_PTR	(&pci_dev_pm_ops)
1356 
1357 #else /* !CONFIG_PM */
1358 
1359 #define pci_pm_runtime_suspend	NULL
1360 #define pci_pm_runtime_resume	NULL
1361 #define pci_pm_runtime_idle	NULL
1362 
1363 #define PCI_PM_OPS_PTR	NULL
1364 
1365 #endif /* !CONFIG_PM */
1366 
1367 /**
1368  * __pci_register_driver - register a new pci driver
1369  * @drv: the driver structure to register
1370  * @owner: owner module of drv
1371  * @mod_name: module name string
1372  *
1373  * Adds the driver structure to the list of registered drivers.
1374  * Returns a negative value on error, otherwise 0.
1375  * If no error occurred, the driver remains registered even if
1376  * no device was claimed during registration.
1377  */
__pci_register_driver(struct pci_driver * drv,struct module * owner,const char * mod_name)1378 int __pci_register_driver(struct pci_driver *drv, struct module *owner,
1379 			  const char *mod_name)
1380 {
1381 	/* initialize common driver fields */
1382 	drv->driver.name = drv->name;
1383 	drv->driver.bus = &pci_bus_type;
1384 	drv->driver.owner = owner;
1385 	drv->driver.mod_name = mod_name;
1386 	drv->driver.groups = drv->groups;
1387 
1388 	spin_lock_init(&drv->dynids.lock);
1389 	INIT_LIST_HEAD(&drv->dynids.list);
1390 
1391 	/* register with core */
1392 	return driver_register(&drv->driver);
1393 }
1394 EXPORT_SYMBOL(__pci_register_driver);
1395 
1396 /**
1397  * pci_unregister_driver - unregister a pci driver
1398  * @drv: the driver structure to unregister
1399  *
1400  * Deletes the driver structure from the list of registered PCI drivers,
1401  * gives it a chance to clean up by calling its remove() function for
1402  * each device it was responsible for, and marks those devices as
1403  * driverless.
1404  */
1405 
pci_unregister_driver(struct pci_driver * drv)1406 void pci_unregister_driver(struct pci_driver *drv)
1407 {
1408 	driver_unregister(&drv->driver);
1409 	pci_free_dynids(drv);
1410 }
1411 EXPORT_SYMBOL(pci_unregister_driver);
1412 
1413 static struct pci_driver pci_compat_driver = {
1414 	.name = "compat"
1415 };
1416 
1417 /**
1418  * pci_dev_driver - get the pci_driver of a device
1419  * @dev: the device to query
1420  *
1421  * Returns the appropriate pci_driver structure or %NULL if there is no
1422  * registered driver for the device.
1423  */
pci_dev_driver(const struct pci_dev * dev)1424 struct pci_driver *pci_dev_driver(const struct pci_dev *dev)
1425 {
1426 	if (dev->driver)
1427 		return dev->driver;
1428 	else {
1429 		int i;
1430 		for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1431 			if (dev->resource[i].flags & IORESOURCE_BUSY)
1432 				return &pci_compat_driver;
1433 	}
1434 	return NULL;
1435 }
1436 EXPORT_SYMBOL(pci_dev_driver);
1437 
1438 /**
1439  * pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure
1440  * @dev: the PCI device structure to match against
1441  * @drv: the device driver to search for matching PCI device id structures
1442  *
1443  * Used by a driver to check whether a PCI device present in the
1444  * system is in its list of supported devices. Returns the matching
1445  * pci_device_id structure or %NULL if there is no match.
1446  */
pci_bus_match(struct device * dev,struct device_driver * drv)1447 static int pci_bus_match(struct device *dev, struct device_driver *drv)
1448 {
1449 	struct pci_dev *pci_dev = to_pci_dev(dev);
1450 	struct pci_driver *pci_drv;
1451 	const struct pci_device_id *found_id;
1452 
1453 	if (!pci_dev->match_driver)
1454 		return 0;
1455 
1456 	pci_drv = to_pci_driver(drv);
1457 	found_id = pci_match_device(pci_drv, pci_dev);
1458 	if (found_id)
1459 		return 1;
1460 
1461 	return 0;
1462 }
1463 
1464 /**
1465  * pci_dev_get - increments the reference count of the pci device structure
1466  * @dev: the device being referenced
1467  *
1468  * Each live reference to a device should be refcounted.
1469  *
1470  * Drivers for PCI devices should normally record such references in
1471  * their probe() methods, when they bind to a device, and release
1472  * them by calling pci_dev_put(), in their disconnect() methods.
1473  *
1474  * A pointer to the device with the incremented reference counter is returned.
1475  */
pci_dev_get(struct pci_dev * dev)1476 struct pci_dev *pci_dev_get(struct pci_dev *dev)
1477 {
1478 	if (dev)
1479 		get_device(&dev->dev);
1480 	return dev;
1481 }
1482 EXPORT_SYMBOL(pci_dev_get);
1483 
1484 /**
1485  * pci_dev_put - release a use of the pci device structure
1486  * @dev: device that's been disconnected
1487  *
1488  * Must be called when a user of a device is finished with it.  When the last
1489  * user of the device calls this function, the memory of the device is freed.
1490  */
pci_dev_put(struct pci_dev * dev)1491 void pci_dev_put(struct pci_dev *dev)
1492 {
1493 	if (dev)
1494 		put_device(&dev->dev);
1495 }
1496 EXPORT_SYMBOL(pci_dev_put);
1497 
pci_uevent(struct device * dev,struct kobj_uevent_env * env)1498 static int pci_uevent(struct device *dev, struct kobj_uevent_env *env)
1499 {
1500 	struct pci_dev *pdev;
1501 
1502 	if (!dev)
1503 		return -ENODEV;
1504 
1505 	pdev = to_pci_dev(dev);
1506 
1507 	if (add_uevent_var(env, "PCI_CLASS=%04X", pdev->class))
1508 		return -ENOMEM;
1509 
1510 	if (add_uevent_var(env, "PCI_ID=%04X:%04X", pdev->vendor, pdev->device))
1511 		return -ENOMEM;
1512 
1513 	if (add_uevent_var(env, "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,
1514 			   pdev->subsystem_device))
1515 		return -ENOMEM;
1516 
1517 	if (add_uevent_var(env, "PCI_SLOT_NAME=%s", pci_name(pdev)))
1518 		return -ENOMEM;
1519 
1520 	if (add_uevent_var(env, "MODALIAS=pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X",
1521 			   pdev->vendor, pdev->device,
1522 			   pdev->subsystem_vendor, pdev->subsystem_device,
1523 			   (u8)(pdev->class >> 16), (u8)(pdev->class >> 8),
1524 			   (u8)(pdev->class)))
1525 		return -ENOMEM;
1526 
1527 	return 0;
1528 }
1529 
1530 #if defined(CONFIG_PCIEPORTBUS) || defined(CONFIG_EEH)
1531 /**
1532  * pci_uevent_ers - emit a uevent during recovery path of PCI device
1533  * @pdev: PCI device undergoing error recovery
1534  * @err_type: type of error event
1535  */
pci_uevent_ers(struct pci_dev * pdev,enum pci_ers_result err_type)1536 void pci_uevent_ers(struct pci_dev *pdev, enum pci_ers_result err_type)
1537 {
1538 	int idx = 0;
1539 	char *envp[3];
1540 
1541 	switch (err_type) {
1542 	case PCI_ERS_RESULT_NONE:
1543 	case PCI_ERS_RESULT_CAN_RECOVER:
1544 		envp[idx++] = "ERROR_EVENT=BEGIN_RECOVERY";
1545 		envp[idx++] = "DEVICE_ONLINE=0";
1546 		break;
1547 	case PCI_ERS_RESULT_RECOVERED:
1548 		envp[idx++] = "ERROR_EVENT=SUCCESSFUL_RECOVERY";
1549 		envp[idx++] = "DEVICE_ONLINE=1";
1550 		break;
1551 	case PCI_ERS_RESULT_DISCONNECT:
1552 		envp[idx++] = "ERROR_EVENT=FAILED_RECOVERY";
1553 		envp[idx++] = "DEVICE_ONLINE=0";
1554 		break;
1555 	default:
1556 		break;
1557 	}
1558 
1559 	if (idx > 0) {
1560 		envp[idx++] = NULL;
1561 		kobject_uevent_env(&pdev->dev.kobj, KOBJ_CHANGE, envp);
1562 	}
1563 }
1564 #endif
1565 
pci_bus_num_vf(struct device * dev)1566 static int pci_bus_num_vf(struct device *dev)
1567 {
1568 	return pci_num_vf(to_pci_dev(dev));
1569 }
1570 
1571 /**
1572  * pci_dma_configure - Setup DMA configuration
1573  * @dev: ptr to dev structure
1574  *
1575  * Function to update PCI devices's DMA configuration using the same
1576  * info from the OF node or ACPI node of host bridge's parent (if any).
1577  */
pci_dma_configure(struct device * dev)1578 static int pci_dma_configure(struct device *dev)
1579 {
1580 	struct device *bridge;
1581 	int ret = 0;
1582 
1583 	bridge = pci_get_host_bridge_device(to_pci_dev(dev));
1584 
1585 	if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
1586 	    bridge->parent->of_node) {
1587 		ret = of_dma_configure(dev, bridge->parent->of_node, true);
1588 	} else if (has_acpi_companion(bridge)) {
1589 		struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
1590 
1591 		ret = acpi_dma_configure(dev, acpi_get_dma_attr(adev));
1592 	}
1593 
1594 	pci_put_host_bridge_device(bridge);
1595 	return ret;
1596 }
1597 
1598 struct bus_type pci_bus_type = {
1599 	.name		= "pci",
1600 	.match		= pci_bus_match,
1601 	.uevent		= pci_uevent,
1602 	.probe		= pci_device_probe,
1603 	.remove		= pci_device_remove,
1604 	.shutdown	= pci_device_shutdown,
1605 	.dev_groups	= pci_dev_groups,
1606 	.bus_groups	= pci_bus_groups,
1607 	.drv_groups	= pci_drv_groups,
1608 	.pm		= PCI_PM_OPS_PTR,
1609 	.num_vf		= pci_bus_num_vf,
1610 	.dma_configure	= pci_dma_configure,
1611 };
1612 EXPORT_SYMBOL(pci_bus_type);
1613 
1614 #ifdef CONFIG_PCIEPORTBUS
pcie_port_bus_match(struct device * dev,struct device_driver * drv)1615 static int pcie_port_bus_match(struct device *dev, struct device_driver *drv)
1616 {
1617 	struct pcie_device *pciedev;
1618 	struct pcie_port_service_driver *driver;
1619 
1620 	if (drv->bus != &pcie_port_bus_type || dev->bus != &pcie_port_bus_type)
1621 		return 0;
1622 
1623 	pciedev = to_pcie_device(dev);
1624 	driver = to_service_driver(drv);
1625 
1626 	if (driver->service != pciedev->service)
1627 		return 0;
1628 
1629 	if (driver->port_type != PCIE_ANY_PORT &&
1630 	    driver->port_type != pci_pcie_type(pciedev->port))
1631 		return 0;
1632 
1633 	return 1;
1634 }
1635 
1636 struct bus_type pcie_port_bus_type = {
1637 	.name		= "pci_express",
1638 	.match		= pcie_port_bus_match,
1639 };
1640 EXPORT_SYMBOL_GPL(pcie_port_bus_type);
1641 #endif
1642 
pci_driver_init(void)1643 static int __init pci_driver_init(void)
1644 {
1645 	int ret;
1646 
1647 	ret = bus_register(&pci_bus_type);
1648 	if (ret)
1649 		return ret;
1650 
1651 #ifdef CONFIG_PCIEPORTBUS
1652 	ret = bus_register(&pcie_port_bus_type);
1653 	if (ret)
1654 		return ret;
1655 #endif
1656 	dma_debug_add_bus(&pci_bus_type);
1657 	return 0;
1658 }
1659 postcore_initcall(pci_driver_init);
1660