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 <linux/iommu.h>
24 #include "pci.h"
25 #include "pcie/portdrv.h"
26 
27 struct pci_dynid {
28 	struct list_head node;
29 	struct pci_device_id id;
30 };
31 
32 /**
33  * pci_add_dynid - add a new PCI device ID to this driver and re-probe devices
34  * @drv: target pci driver
35  * @vendor: PCI vendor ID
36  * @device: PCI device ID
37  * @subvendor: PCI subvendor ID
38  * @subdevice: PCI subdevice ID
39  * @class: PCI class
40  * @class_mask: PCI class mask
41  * @driver_data: private driver data
42  *
43  * Adds a new dynamic pci device ID to this driver and causes the
44  * driver to probe for all devices again.  @drv must have been
45  * registered prior to calling this function.
46  *
47  * CONTEXT:
48  * Does GFP_KERNEL allocation.
49  *
50  * RETURNS:
51  * 0 on success, -errno on failure.
52  */
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)53 int pci_add_dynid(struct pci_driver *drv,
54 		  unsigned int vendor, unsigned int device,
55 		  unsigned int subvendor, unsigned int subdevice,
56 		  unsigned int class, unsigned int class_mask,
57 		  unsigned long driver_data)
58 {
59 	struct pci_dynid *dynid;
60 
61 	dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
62 	if (!dynid)
63 		return -ENOMEM;
64 
65 	dynid->id.vendor = vendor;
66 	dynid->id.device = device;
67 	dynid->id.subvendor = subvendor;
68 	dynid->id.subdevice = subdevice;
69 	dynid->id.class = class;
70 	dynid->id.class_mask = class_mask;
71 	dynid->id.driver_data = driver_data;
72 
73 	spin_lock(&drv->dynids.lock);
74 	list_add_tail(&dynid->node, &drv->dynids.list);
75 	spin_unlock(&drv->dynids.lock);
76 
77 	return driver_attach(&drv->driver);
78 }
79 EXPORT_SYMBOL_GPL(pci_add_dynid);
80 
pci_free_dynids(struct pci_driver * drv)81 static void pci_free_dynids(struct pci_driver *drv)
82 {
83 	struct pci_dynid *dynid, *n;
84 
85 	spin_lock(&drv->dynids.lock);
86 	list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
87 		list_del(&dynid->node);
88 		kfree(dynid);
89 	}
90 	spin_unlock(&drv->dynids.lock);
91 }
92 
93 /**
94  * pci_match_id - See if a PCI device matches a given pci_id table
95  * @ids: array of PCI device ID structures to search in
96  * @dev: the PCI device structure to match against.
97  *
98  * Used by a driver to check whether a PCI device is in its list of
99  * supported devices.  Returns the matching pci_device_id structure or
100  * %NULL if there is no match.
101  *
102  * Deprecated; don't use this as it will not catch any dynamic IDs
103  * that a driver might want to check for.
104  */
pci_match_id(const struct pci_device_id * ids,struct pci_dev * dev)105 const struct pci_device_id *pci_match_id(const struct pci_device_id *ids,
106 					 struct pci_dev *dev)
107 {
108 	if (ids) {
109 		while (ids->vendor || ids->subvendor || ids->class_mask) {
110 			if (pci_match_one_device(ids, dev))
111 				return ids;
112 			ids++;
113 		}
114 	}
115 	return NULL;
116 }
117 EXPORT_SYMBOL(pci_match_id);
118 
119 static const struct pci_device_id pci_device_id_any = {
120 	.vendor = PCI_ANY_ID,
121 	.device = PCI_ANY_ID,
122 	.subvendor = PCI_ANY_ID,
123 	.subdevice = PCI_ANY_ID,
124 };
125 
126 /**
127  * pci_match_device - See if a device matches a driver's list of IDs
128  * @drv: the PCI driver to match against
129  * @dev: the PCI device structure to match against
130  *
131  * Used by a driver to check whether a PCI device is in its list of
132  * supported devices or in the dynids list, which may have been augmented
133  * via the sysfs "new_id" file.  Returns the matching pci_device_id
134  * structure or %NULL if there is no match.
135  */
pci_match_device(struct pci_driver * drv,struct pci_dev * dev)136 static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
137 						    struct pci_dev *dev)
138 {
139 	struct pci_dynid *dynid;
140 	const struct pci_device_id *found_id = NULL, *ids;
141 
142 	/* When driver_override is set, only bind to the matching driver */
143 	if (dev->driver_override && strcmp(dev->driver_override, drv->name))
144 		return NULL;
145 
146 	/* Look at the dynamic ids first, before the static ones */
147 	spin_lock(&drv->dynids.lock);
148 	list_for_each_entry(dynid, &drv->dynids.list, node) {
149 		if (pci_match_one_device(&dynid->id, dev)) {
150 			found_id = &dynid->id;
151 			break;
152 		}
153 	}
154 	spin_unlock(&drv->dynids.lock);
155 
156 	if (found_id)
157 		return found_id;
158 
159 	for (ids = drv->id_table; (found_id = pci_match_id(ids, dev));
160 	     ids = found_id + 1) {
161 		/*
162 		 * The match table is split based on driver_override.
163 		 * In case override_only was set, enforce driver_override
164 		 * matching.
165 		 */
166 		if (found_id->override_only) {
167 			if (dev->driver_override)
168 				return found_id;
169 		} else {
170 			return found_id;
171 		}
172 	}
173 
174 	/* driver_override will always match, send a dummy id */
175 	if (dev->driver_override)
176 		return &pci_device_id_any;
177 	return NULL;
178 }
179 
180 /**
181  * new_id_store - sysfs frontend to pci_add_dynid()
182  * @driver: target device driver
183  * @buf: buffer for scanning device ID data
184  * @count: input size
185  *
186  * Allow PCI IDs to be added to an existing driver via sysfs.
187  */
new_id_store(struct device_driver * driver,const char * buf,size_t count)188 static ssize_t new_id_store(struct device_driver *driver, const char *buf,
189 			    size_t count)
190 {
191 	struct pci_driver *pdrv = to_pci_driver(driver);
192 	const struct pci_device_id *ids = pdrv->id_table;
193 	u32 vendor, device, subvendor = PCI_ANY_ID,
194 		subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
195 	unsigned long driver_data = 0;
196 	int fields = 0;
197 	int retval = 0;
198 
199 	fields = sscanf(buf, "%x %x %x %x %x %x %lx",
200 			&vendor, &device, &subvendor, &subdevice,
201 			&class, &class_mask, &driver_data);
202 	if (fields < 2)
203 		return -EINVAL;
204 
205 	if (fields != 7) {
206 		struct pci_dev *pdev = kzalloc(sizeof(*pdev), GFP_KERNEL);
207 		if (!pdev)
208 			return -ENOMEM;
209 
210 		pdev->vendor = vendor;
211 		pdev->device = device;
212 		pdev->subsystem_vendor = subvendor;
213 		pdev->subsystem_device = subdevice;
214 		pdev->class = class;
215 
216 		if (pci_match_device(pdrv, pdev))
217 			retval = -EEXIST;
218 
219 		kfree(pdev);
220 
221 		if (retval)
222 			return retval;
223 	}
224 
225 	/* Only accept driver_data values that match an existing id_table
226 	   entry */
227 	if (ids) {
228 		retval = -EINVAL;
229 		while (ids->vendor || ids->subvendor || ids->class_mask) {
230 			if (driver_data == ids->driver_data) {
231 				retval = 0;
232 				break;
233 			}
234 			ids++;
235 		}
236 		if (retval)	/* No match */
237 			return retval;
238 	}
239 
240 	retval = pci_add_dynid(pdrv, vendor, device, subvendor, subdevice,
241 			       class, class_mask, driver_data);
242 	if (retval)
243 		return retval;
244 	return count;
245 }
246 static DRIVER_ATTR_WO(new_id);
247 
248 /**
249  * remove_id_store - remove a PCI device ID from this driver
250  * @driver: target device driver
251  * @buf: buffer for scanning device ID data
252  * @count: input size
253  *
254  * Removes a dynamic pci device ID to this driver.
255  */
remove_id_store(struct device_driver * driver,const char * buf,size_t count)256 static ssize_t remove_id_store(struct device_driver *driver, const char *buf,
257 			       size_t count)
258 {
259 	struct pci_dynid *dynid, *n;
260 	struct pci_driver *pdrv = to_pci_driver(driver);
261 	u32 vendor, device, subvendor = PCI_ANY_ID,
262 		subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
263 	int fields = 0;
264 	size_t retval = -ENODEV;
265 
266 	fields = sscanf(buf, "%x %x %x %x %x %x",
267 			&vendor, &device, &subvendor, &subdevice,
268 			&class, &class_mask);
269 	if (fields < 2)
270 		return -EINVAL;
271 
272 	spin_lock(&pdrv->dynids.lock);
273 	list_for_each_entry_safe(dynid, n, &pdrv->dynids.list, node) {
274 		struct pci_device_id *id = &dynid->id;
275 		if ((id->vendor == vendor) &&
276 		    (id->device == device) &&
277 		    (subvendor == PCI_ANY_ID || id->subvendor == subvendor) &&
278 		    (subdevice == PCI_ANY_ID || id->subdevice == subdevice) &&
279 		    !((id->class ^ class) & class_mask)) {
280 			list_del(&dynid->node);
281 			kfree(dynid);
282 			retval = count;
283 			break;
284 		}
285 	}
286 	spin_unlock(&pdrv->dynids.lock);
287 
288 	return retval;
289 }
290 static DRIVER_ATTR_WO(remove_id);
291 
292 static struct attribute *pci_drv_attrs[] = {
293 	&driver_attr_new_id.attr,
294 	&driver_attr_remove_id.attr,
295 	NULL,
296 };
297 ATTRIBUTE_GROUPS(pci_drv);
298 
299 struct drv_dev_and_id {
300 	struct pci_driver *drv;
301 	struct pci_dev *dev;
302 	const struct pci_device_id *id;
303 };
304 
local_pci_probe(void * _ddi)305 static long local_pci_probe(void *_ddi)
306 {
307 	struct drv_dev_and_id *ddi = _ddi;
308 	struct pci_dev *pci_dev = ddi->dev;
309 	struct pci_driver *pci_drv = ddi->drv;
310 	struct device *dev = &pci_dev->dev;
311 	int rc;
312 
313 	/*
314 	 * Unbound PCI devices are always put in D0, regardless of
315 	 * runtime PM status.  During probe, the device is set to
316 	 * active and the usage count is incremented.  If the driver
317 	 * supports runtime PM, it should call pm_runtime_put_noidle(),
318 	 * or any other runtime PM helper function decrementing the usage
319 	 * count, in its probe routine and pm_runtime_get_noresume() in
320 	 * its remove routine.
321 	 */
322 	pm_runtime_get_sync(dev);
323 	pci_dev->driver = pci_drv;
324 	rc = pci_drv->probe(pci_dev, ddi->id);
325 	if (!rc)
326 		return rc;
327 	if (rc < 0) {
328 		pci_dev->driver = NULL;
329 		pm_runtime_put_sync(dev);
330 		return rc;
331 	}
332 	/*
333 	 * Probe function should return < 0 for failure, 0 for success
334 	 * Treat values > 0 as success, but warn.
335 	 */
336 	pci_warn(pci_dev, "Driver probe function unexpectedly returned %d\n",
337 		 rc);
338 	return 0;
339 }
340 
pci_physfn_is_probed(struct pci_dev * dev)341 static bool pci_physfn_is_probed(struct pci_dev *dev)
342 {
343 #ifdef CONFIG_PCI_IOV
344 	return dev->is_virtfn && dev->physfn->is_probed;
345 #else
346 	return false;
347 #endif
348 }
349 
pci_call_probe(struct pci_driver * drv,struct pci_dev * dev,const struct pci_device_id * id)350 static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
351 			  const struct pci_device_id *id)
352 {
353 	int error, node, cpu;
354 	struct drv_dev_and_id ddi = { drv, dev, id };
355 
356 	/*
357 	 * Execute driver initialization on node where the device is
358 	 * attached.  This way the driver likely allocates its local memory
359 	 * on the right node.
360 	 */
361 	node = dev_to_node(&dev->dev);
362 	dev->is_probed = 1;
363 
364 	cpu_hotplug_disable();
365 
366 	/*
367 	 * Prevent nesting work_on_cpu() for the case where a Virtual Function
368 	 * device is probed from work_on_cpu() of the Physical device.
369 	 */
370 	if (node < 0 || node >= MAX_NUMNODES || !node_online(node) ||
371 	    pci_physfn_is_probed(dev)) {
372 		cpu = nr_cpu_ids;
373 	} else {
374 		cpumask_var_t wq_domain_mask;
375 
376 		if (!zalloc_cpumask_var(&wq_domain_mask, GFP_KERNEL)) {
377 			error = -ENOMEM;
378 			goto out;
379 		}
380 		cpumask_and(wq_domain_mask,
381 			    housekeeping_cpumask(HK_TYPE_WQ),
382 			    housekeeping_cpumask(HK_TYPE_DOMAIN));
383 
384 		cpu = cpumask_any_and(cpumask_of_node(node),
385 				      wq_domain_mask);
386 		free_cpumask_var(wq_domain_mask);
387 	}
388 
389 	if (cpu < nr_cpu_ids)
390 		error = work_on_cpu(cpu, local_pci_probe, &ddi);
391 	else
392 		error = local_pci_probe(&ddi);
393 out:
394 	dev->is_probed = 0;
395 	cpu_hotplug_enable();
396 	return error;
397 }
398 
399 /**
400  * __pci_device_probe - check if a driver wants to claim a specific PCI device
401  * @drv: driver to call to check if it wants the PCI device
402  * @pci_dev: PCI device being probed
403  *
404  * returns 0 on success, else error.
405  * side-effect: pci_dev->driver is set to drv when drv claims pci_dev.
406  */
__pci_device_probe(struct pci_driver * drv,struct pci_dev * pci_dev)407 static int __pci_device_probe(struct pci_driver *drv, struct pci_dev *pci_dev)
408 {
409 	const struct pci_device_id *id;
410 	int error = 0;
411 
412 	if (drv->probe) {
413 		error = -ENODEV;
414 
415 		id = pci_match_device(drv, pci_dev);
416 		if (id)
417 			error = pci_call_probe(drv, pci_dev, id);
418 	}
419 	return error;
420 }
421 
pcibios_alloc_irq(struct pci_dev * dev)422 int __weak pcibios_alloc_irq(struct pci_dev *dev)
423 {
424 	return 0;
425 }
426 
pcibios_free_irq(struct pci_dev * dev)427 void __weak pcibios_free_irq(struct pci_dev *dev)
428 {
429 }
430 
431 #ifdef CONFIG_PCI_IOV
pci_device_can_probe(struct pci_dev * pdev)432 static inline bool pci_device_can_probe(struct pci_dev *pdev)
433 {
434 	return (!pdev->is_virtfn || pdev->physfn->sriov->drivers_autoprobe ||
435 		pdev->driver_override);
436 }
437 #else
pci_device_can_probe(struct pci_dev * pdev)438 static inline bool pci_device_can_probe(struct pci_dev *pdev)
439 {
440 	return true;
441 }
442 #endif
443 
pci_device_probe(struct device * dev)444 static int pci_device_probe(struct device *dev)
445 {
446 	int error;
447 	struct pci_dev *pci_dev = to_pci_dev(dev);
448 	struct pci_driver *drv = to_pci_driver(dev->driver);
449 
450 	if (!pci_device_can_probe(pci_dev))
451 		return -ENODEV;
452 
453 	pci_assign_irq(pci_dev);
454 
455 	error = pcibios_alloc_irq(pci_dev);
456 	if (error < 0)
457 		return error;
458 
459 	pci_dev_get(pci_dev);
460 	error = __pci_device_probe(drv, pci_dev);
461 	if (error) {
462 		pcibios_free_irq(pci_dev);
463 		pci_dev_put(pci_dev);
464 	}
465 
466 	return error;
467 }
468 
pci_device_remove(struct device * dev)469 static void pci_device_remove(struct device *dev)
470 {
471 	struct pci_dev *pci_dev = to_pci_dev(dev);
472 	struct pci_driver *drv = pci_dev->driver;
473 
474 	if (drv->remove) {
475 		pm_runtime_get_sync(dev);
476 		drv->remove(pci_dev);
477 		pm_runtime_put_noidle(dev);
478 	}
479 	pcibios_free_irq(pci_dev);
480 	pci_dev->driver = NULL;
481 	pci_iov_remove(pci_dev);
482 
483 	/* Undo the runtime PM settings in local_pci_probe() */
484 	pm_runtime_put_sync(dev);
485 
486 	/*
487 	 * If the device is still on, set the power state as "unknown",
488 	 * since it might change by the next time we load the driver.
489 	 */
490 	if (pci_dev->current_state == PCI_D0)
491 		pci_dev->current_state = PCI_UNKNOWN;
492 
493 	/*
494 	 * We would love to complain here if pci_dev->is_enabled is set, that
495 	 * the driver should have called pci_disable_device(), but the
496 	 * unfortunate fact is there are too many odd BIOS and bridge setups
497 	 * that don't like drivers doing that all of the time.
498 	 * Oh well, we can dream of sane hardware when we sleep, no matter how
499 	 * horrible the crap we have to deal with is when we are awake...
500 	 */
501 
502 	pci_dev_put(pci_dev);
503 }
504 
pci_device_shutdown(struct device * dev)505 static void pci_device_shutdown(struct device *dev)
506 {
507 	struct pci_dev *pci_dev = to_pci_dev(dev);
508 	struct pci_driver *drv = pci_dev->driver;
509 
510 	pm_runtime_resume(dev);
511 
512 	if (drv && drv->shutdown)
513 		drv->shutdown(pci_dev);
514 
515 	/*
516 	 * If this is a kexec reboot, turn off Bus Master bit on the
517 	 * device to tell it to not continue to do DMA. Don't touch
518 	 * devices in D3cold or unknown states.
519 	 * If it is not a kexec reboot, firmware will hit the PCI
520 	 * devices with big hammer and stop their DMA any way.
521 	 */
522 	if (kexec_in_progress && (pci_dev->current_state <= PCI_D3hot))
523 		pci_clear_master(pci_dev);
524 }
525 
526 #ifdef CONFIG_PM_SLEEP
527 
528 /* Auxiliary functions used for system resume */
529 
530 /**
531  * pci_restore_standard_config - restore standard config registers of PCI device
532  * @pci_dev: PCI device to handle
533  */
pci_restore_standard_config(struct pci_dev * pci_dev)534 static int pci_restore_standard_config(struct pci_dev *pci_dev)
535 {
536 	pci_update_current_state(pci_dev, PCI_UNKNOWN);
537 
538 	if (pci_dev->current_state != PCI_D0) {
539 		int error = pci_set_power_state(pci_dev, PCI_D0);
540 		if (error)
541 			return error;
542 	}
543 
544 	pci_restore_state(pci_dev);
545 	pci_pme_restore(pci_dev);
546 	return 0;
547 }
548 #endif /* CONFIG_PM_SLEEP */
549 
550 #ifdef CONFIG_PM
551 
552 /* Auxiliary functions used for system resume and run-time resume */
553 
pci_pm_default_resume(struct pci_dev * pci_dev)554 static void pci_pm_default_resume(struct pci_dev *pci_dev)
555 {
556 	pci_fixup_device(pci_fixup_resume, pci_dev);
557 	pci_enable_wake(pci_dev, PCI_D0, false);
558 }
559 
pci_pm_power_up_and_verify_state(struct pci_dev * pci_dev)560 static void pci_pm_power_up_and_verify_state(struct pci_dev *pci_dev)
561 {
562 	pci_power_up(pci_dev);
563 	pci_update_current_state(pci_dev, PCI_D0);
564 }
565 
pci_pm_default_resume_early(struct pci_dev * pci_dev)566 static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
567 {
568 	pci_pm_power_up_and_verify_state(pci_dev);
569 	pci_restore_state(pci_dev);
570 	pci_pme_restore(pci_dev);
571 }
572 
pci_pm_bridge_power_up_actions(struct pci_dev * pci_dev)573 static void pci_pm_bridge_power_up_actions(struct pci_dev *pci_dev)
574 {
575 	pci_bridge_wait_for_secondary_bus(pci_dev);
576 	/*
577 	 * When powering on a bridge from D3cold, the whole hierarchy may be
578 	 * powered on into D0uninitialized state, resume them to give them a
579 	 * chance to suspend again
580 	 */
581 	pci_resume_bus(pci_dev->subordinate);
582 }
583 
584 #endif /* CONFIG_PM */
585 
586 #ifdef CONFIG_PM_SLEEP
587 
588 /*
589  * Default "suspend" method for devices that have no driver provided suspend,
590  * or not even a driver at all (second part).
591  */
pci_pm_set_unknown_state(struct pci_dev * pci_dev)592 static void pci_pm_set_unknown_state(struct pci_dev *pci_dev)
593 {
594 	/*
595 	 * mark its power state as "unknown", since we don't know if
596 	 * e.g. the BIOS will change its device state when we suspend.
597 	 */
598 	if (pci_dev->current_state == PCI_D0)
599 		pci_dev->current_state = PCI_UNKNOWN;
600 }
601 
602 /*
603  * Default "resume" method for devices that have no driver provided resume,
604  * or not even a driver at all (second part).
605  */
pci_pm_reenable_device(struct pci_dev * pci_dev)606 static int pci_pm_reenable_device(struct pci_dev *pci_dev)
607 {
608 	int retval;
609 
610 	/* if the device was enabled before suspend, re-enable */
611 	retval = pci_reenable_device(pci_dev);
612 	/*
613 	 * if the device was busmaster before the suspend, make it busmaster
614 	 * again
615 	 */
616 	if (pci_dev->is_busmaster)
617 		pci_set_master(pci_dev);
618 
619 	return retval;
620 }
621 
pci_legacy_suspend(struct device * dev,pm_message_t state)622 static int pci_legacy_suspend(struct device *dev, pm_message_t state)
623 {
624 	struct pci_dev *pci_dev = to_pci_dev(dev);
625 	struct pci_driver *drv = pci_dev->driver;
626 
627 	if (drv && drv->suspend) {
628 		pci_power_t prev = pci_dev->current_state;
629 		int error;
630 
631 		error = drv->suspend(pci_dev, state);
632 		suspend_report_result(dev, drv->suspend, error);
633 		if (error)
634 			return error;
635 
636 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
637 		    && pci_dev->current_state != PCI_UNKNOWN) {
638 			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
639 				      "PCI PM: Device state not saved by %pS\n",
640 				      drv->suspend);
641 		}
642 	}
643 
644 	pci_fixup_device(pci_fixup_suspend, pci_dev);
645 
646 	return 0;
647 }
648 
pci_legacy_suspend_late(struct device * dev,pm_message_t state)649 static int pci_legacy_suspend_late(struct device *dev, pm_message_t state)
650 {
651 	struct pci_dev *pci_dev = to_pci_dev(dev);
652 
653 	if (!pci_dev->state_saved)
654 		pci_save_state(pci_dev);
655 
656 	pci_pm_set_unknown_state(pci_dev);
657 
658 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
659 
660 	return 0;
661 }
662 
pci_legacy_resume(struct device * dev)663 static int pci_legacy_resume(struct device *dev)
664 {
665 	struct pci_dev *pci_dev = to_pci_dev(dev);
666 	struct pci_driver *drv = pci_dev->driver;
667 
668 	pci_fixup_device(pci_fixup_resume, pci_dev);
669 
670 	return drv && drv->resume ?
671 			drv->resume(pci_dev) : pci_pm_reenable_device(pci_dev);
672 }
673 
674 /* Auxiliary functions used by the new power management framework */
675 
pci_pm_default_suspend(struct pci_dev * pci_dev)676 static void pci_pm_default_suspend(struct pci_dev *pci_dev)
677 {
678 	/* Disable non-bridge devices without PM support */
679 	if (!pci_has_subordinate(pci_dev))
680 		pci_disable_enabled_device(pci_dev);
681 }
682 
pci_has_legacy_pm_support(struct pci_dev * pci_dev)683 static bool pci_has_legacy_pm_support(struct pci_dev *pci_dev)
684 {
685 	struct pci_driver *drv = pci_dev->driver;
686 	bool ret = drv && (drv->suspend || drv->resume);
687 
688 	/*
689 	 * Legacy PM support is used by default, so warn if the new framework is
690 	 * supported as well.  Drivers are supposed to support either the
691 	 * former, or the latter, but not both at the same time.
692 	 */
693 	pci_WARN(pci_dev, ret && drv->driver.pm, "device %04x:%04x\n",
694 		 pci_dev->vendor, pci_dev->device);
695 
696 	return ret;
697 }
698 
699 /* New power management framework */
700 
pci_pm_prepare(struct device * dev)701 static int pci_pm_prepare(struct device *dev)
702 {
703 	struct pci_dev *pci_dev = to_pci_dev(dev);
704 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
705 
706 	if (pm && pm->prepare) {
707 		int error = pm->prepare(dev);
708 		if (error < 0)
709 			return error;
710 
711 		if (!error && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
712 			return 0;
713 	}
714 	if (pci_dev_need_resume(pci_dev))
715 		return 0;
716 
717 	/*
718 	 * The PME setting needs to be adjusted here in case the direct-complete
719 	 * optimization is used with respect to this device.
720 	 */
721 	pci_dev_adjust_pme(pci_dev);
722 	return 1;
723 }
724 
pci_pm_complete(struct device * dev)725 static void pci_pm_complete(struct device *dev)
726 {
727 	struct pci_dev *pci_dev = to_pci_dev(dev);
728 
729 	pci_dev_complete_resume(pci_dev);
730 	pm_generic_complete(dev);
731 
732 	/* Resume device if platform firmware has put it in reset-power-on */
733 	if (pm_runtime_suspended(dev) && pm_resume_via_firmware()) {
734 		pci_power_t pre_sleep_state = pci_dev->current_state;
735 
736 		pci_refresh_power_state(pci_dev);
737 		/*
738 		 * On platforms with ACPI this check may also trigger for
739 		 * devices sharing power resources if one of those power
740 		 * resources has been activated as a result of a change of the
741 		 * power state of another device sharing it.  However, in that
742 		 * case it is also better to resume the device, in general.
743 		 */
744 		if (pci_dev->current_state < pre_sleep_state)
745 			pm_request_resume(dev);
746 	}
747 }
748 
749 #else /* !CONFIG_PM_SLEEP */
750 
751 #define pci_pm_prepare	NULL
752 #define pci_pm_complete	NULL
753 
754 #endif /* !CONFIG_PM_SLEEP */
755 
756 #ifdef CONFIG_SUSPEND
pcie_pme_root_status_cleanup(struct pci_dev * pci_dev)757 static void pcie_pme_root_status_cleanup(struct pci_dev *pci_dev)
758 {
759 	/*
760 	 * Some BIOSes forget to clear Root PME Status bits after system
761 	 * wakeup, which breaks ACPI-based runtime wakeup on PCI Express.
762 	 * Clear those bits now just in case (shouldn't hurt).
763 	 */
764 	if (pci_is_pcie(pci_dev) &&
765 	    (pci_pcie_type(pci_dev) == PCI_EXP_TYPE_ROOT_PORT ||
766 	     pci_pcie_type(pci_dev) == PCI_EXP_TYPE_RC_EC))
767 		pcie_clear_root_pme_status(pci_dev);
768 }
769 
pci_pm_suspend(struct device * dev)770 static int pci_pm_suspend(struct device *dev)
771 {
772 	struct pci_dev *pci_dev = to_pci_dev(dev);
773 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
774 
775 	pci_dev->skip_bus_pm = false;
776 
777 	if (pci_has_legacy_pm_support(pci_dev))
778 		return pci_legacy_suspend(dev, PMSG_SUSPEND);
779 
780 	if (!pm) {
781 		pci_pm_default_suspend(pci_dev);
782 		return 0;
783 	}
784 
785 	/*
786 	 * PCI devices suspended at run time may need to be resumed at this
787 	 * point, because in general it may be necessary to reconfigure them for
788 	 * system suspend.  Namely, if the device is expected to wake up the
789 	 * system from the sleep state, it may have to be reconfigured for this
790 	 * purpose, or if the device is not expected to wake up the system from
791 	 * the sleep state, it should be prevented from signaling wakeup events
792 	 * going forward.
793 	 *
794 	 * Also if the driver of the device does not indicate that its system
795 	 * suspend callbacks can cope with runtime-suspended devices, it is
796 	 * better to resume the device from runtime suspend here.
797 	 */
798 	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
799 	    pci_dev_need_resume(pci_dev)) {
800 		pm_runtime_resume(dev);
801 		pci_dev->state_saved = false;
802 	} else {
803 		pci_dev_adjust_pme(pci_dev);
804 	}
805 
806 	if (pm->suspend) {
807 		pci_power_t prev = pci_dev->current_state;
808 		int error;
809 
810 		error = pm->suspend(dev);
811 		suspend_report_result(dev, pm->suspend, error);
812 		if (error)
813 			return error;
814 
815 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
816 		    && pci_dev->current_state != PCI_UNKNOWN) {
817 			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
818 				      "PCI PM: State of device not saved by %pS\n",
819 				      pm->suspend);
820 		}
821 	}
822 
823 	return 0;
824 }
825 
pci_pm_suspend_late(struct device * dev)826 static int pci_pm_suspend_late(struct device *dev)
827 {
828 	if (dev_pm_skip_suspend(dev))
829 		return 0;
830 
831 	pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));
832 
833 	return pm_generic_suspend_late(dev);
834 }
835 
pci_pm_suspend_noirq(struct device * dev)836 static int pci_pm_suspend_noirq(struct device *dev)
837 {
838 	struct pci_dev *pci_dev = to_pci_dev(dev);
839 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
840 
841 	if (dev_pm_skip_suspend(dev))
842 		return 0;
843 
844 	if (pci_has_legacy_pm_support(pci_dev))
845 		return pci_legacy_suspend_late(dev, PMSG_SUSPEND);
846 
847 	if (!pm) {
848 		pci_save_state(pci_dev);
849 		goto Fixup;
850 	}
851 
852 	if (pm->suspend_noirq) {
853 		pci_power_t prev = pci_dev->current_state;
854 		int error;
855 
856 		error = pm->suspend_noirq(dev);
857 		suspend_report_result(dev, pm->suspend_noirq, error);
858 		if (error)
859 			return error;
860 
861 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
862 		    && pci_dev->current_state != PCI_UNKNOWN) {
863 			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
864 				      "PCI PM: State of device not saved by %pS\n",
865 				      pm->suspend_noirq);
866 			goto Fixup;
867 		}
868 	}
869 
870 	if (pci_dev->skip_bus_pm) {
871 		/*
872 		 * Either the device is a bridge with a child in D0 below it, or
873 		 * the function is running for the second time in a row without
874 		 * going through full resume, which is possible only during
875 		 * suspend-to-idle in a spurious wakeup case.  The device should
876 		 * be in D0 at this point, but if it is a bridge, it may be
877 		 * necessary to save its state.
878 		 */
879 		if (!pci_dev->state_saved)
880 			pci_save_state(pci_dev);
881 	} else if (!pci_dev->state_saved) {
882 		pci_save_state(pci_dev);
883 		if (pci_power_manageable(pci_dev))
884 			pci_prepare_to_sleep(pci_dev);
885 	}
886 
887 	pci_dbg(pci_dev, "PCI PM: Suspend power state: %s\n",
888 		pci_power_name(pci_dev->current_state));
889 
890 	if (pci_dev->current_state == PCI_D0) {
891 		pci_dev->skip_bus_pm = true;
892 		/*
893 		 * Per PCI PM r1.2, table 6-1, a bridge must be in D0 if any
894 		 * downstream device is in D0, so avoid changing the power state
895 		 * of the parent bridge by setting the skip_bus_pm flag for it.
896 		 */
897 		if (pci_dev->bus->self)
898 			pci_dev->bus->self->skip_bus_pm = true;
899 	}
900 
901 	if (pci_dev->skip_bus_pm && pm_suspend_no_platform()) {
902 		pci_dbg(pci_dev, "PCI PM: Skipped\n");
903 		goto Fixup;
904 	}
905 
906 	pci_pm_set_unknown_state(pci_dev);
907 
908 	/*
909 	 * Some BIOSes from ASUS have a bug: If a USB EHCI host controller's
910 	 * PCI COMMAND register isn't 0, the BIOS assumes that the controller
911 	 * hasn't been quiesced and tries to turn it off.  If the controller
912 	 * is already in D3, this can hang or cause memory corruption.
913 	 *
914 	 * Since the value of the COMMAND register doesn't matter once the
915 	 * device has been suspended, we can safely set it to 0 here.
916 	 */
917 	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
918 		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
919 
920 Fixup:
921 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
922 
923 	/*
924 	 * If the target system sleep state is suspend-to-idle, it is sufficient
925 	 * to check whether or not the device's wakeup settings are good for
926 	 * runtime PM.  Otherwise, the pm_resume_via_firmware() check will cause
927 	 * pci_pm_complete() to take care of fixing up the device's state
928 	 * anyway, if need be.
929 	 */
930 	if (device_can_wakeup(dev) && !device_may_wakeup(dev))
931 		dev->power.may_skip_resume = false;
932 
933 	return 0;
934 }
935 
pci_pm_resume_noirq(struct device * dev)936 static int pci_pm_resume_noirq(struct device *dev)
937 {
938 	struct pci_dev *pci_dev = to_pci_dev(dev);
939 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
940 	pci_power_t prev_state = pci_dev->current_state;
941 	bool skip_bus_pm = pci_dev->skip_bus_pm;
942 
943 	if (dev_pm_skip_resume(dev))
944 		return 0;
945 
946 	/*
947 	 * In the suspend-to-idle case, devices left in D0 during suspend will
948 	 * stay in D0, so it is not necessary to restore or update their
949 	 * configuration here and attempting to put them into D0 again is
950 	 * pointless, so avoid doing that.
951 	 */
952 	if (!(skip_bus_pm && pm_suspend_no_platform()))
953 		pci_pm_default_resume_early(pci_dev);
954 
955 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
956 	pcie_pme_root_status_cleanup(pci_dev);
957 
958 	if (!skip_bus_pm && prev_state == PCI_D3cold)
959 		pci_pm_bridge_power_up_actions(pci_dev);
960 
961 	if (pci_has_legacy_pm_support(pci_dev))
962 		return 0;
963 
964 	if (pm && pm->resume_noirq)
965 		return pm->resume_noirq(dev);
966 
967 	return 0;
968 }
969 
pci_pm_resume_early(struct device * dev)970 static int pci_pm_resume_early(struct device *dev)
971 {
972 	if (dev_pm_skip_resume(dev))
973 		return 0;
974 
975 	return pm_generic_resume_early(dev);
976 }
977 
pci_pm_resume(struct device * dev)978 static int pci_pm_resume(struct device *dev)
979 {
980 	struct pci_dev *pci_dev = to_pci_dev(dev);
981 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
982 
983 	/*
984 	 * This is necessary for the suspend error path in which resume is
985 	 * called without restoring the standard config registers of the device.
986 	 */
987 	if (pci_dev->state_saved)
988 		pci_restore_standard_config(pci_dev);
989 
990 	if (pci_has_legacy_pm_support(pci_dev))
991 		return pci_legacy_resume(dev);
992 
993 	pci_pm_default_resume(pci_dev);
994 
995 	if (pm) {
996 		if (pm->resume)
997 			return pm->resume(dev);
998 	} else {
999 		pci_pm_reenable_device(pci_dev);
1000 	}
1001 
1002 	return 0;
1003 }
1004 
1005 #else /* !CONFIG_SUSPEND */
1006 
1007 #define pci_pm_suspend		NULL
1008 #define pci_pm_suspend_late	NULL
1009 #define pci_pm_suspend_noirq	NULL
1010 #define pci_pm_resume		NULL
1011 #define pci_pm_resume_early	NULL
1012 #define pci_pm_resume_noirq	NULL
1013 
1014 #endif /* !CONFIG_SUSPEND */
1015 
1016 #ifdef CONFIG_HIBERNATE_CALLBACKS
1017 
pci_pm_freeze(struct device * dev)1018 static int pci_pm_freeze(struct device *dev)
1019 {
1020 	struct pci_dev *pci_dev = to_pci_dev(dev);
1021 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1022 
1023 	if (pci_has_legacy_pm_support(pci_dev))
1024 		return pci_legacy_suspend(dev, PMSG_FREEZE);
1025 
1026 	if (!pm) {
1027 		pci_pm_default_suspend(pci_dev);
1028 		return 0;
1029 	}
1030 
1031 	/*
1032 	 * Resume all runtime-suspended devices before creating a snapshot
1033 	 * image of system memory, because the restore kernel generally cannot
1034 	 * be expected to always handle them consistently and they need to be
1035 	 * put into the runtime-active metastate during system resume anyway,
1036 	 * so it is better to ensure that the state saved in the image will be
1037 	 * always consistent with that.
1038 	 */
1039 	pm_runtime_resume(dev);
1040 	pci_dev->state_saved = false;
1041 
1042 	if (pm->freeze) {
1043 		int error;
1044 
1045 		error = pm->freeze(dev);
1046 		suspend_report_result(dev, pm->freeze, error);
1047 		if (error)
1048 			return error;
1049 	}
1050 
1051 	return 0;
1052 }
1053 
pci_pm_freeze_noirq(struct device * dev)1054 static int pci_pm_freeze_noirq(struct device *dev)
1055 {
1056 	struct pci_dev *pci_dev = to_pci_dev(dev);
1057 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1058 
1059 	if (pci_has_legacy_pm_support(pci_dev))
1060 		return pci_legacy_suspend_late(dev, PMSG_FREEZE);
1061 
1062 	if (pm && pm->freeze_noirq) {
1063 		int error;
1064 
1065 		error = pm->freeze_noirq(dev);
1066 		suspend_report_result(dev, pm->freeze_noirq, error);
1067 		if (error)
1068 			return error;
1069 	}
1070 
1071 	if (!pci_dev->state_saved)
1072 		pci_save_state(pci_dev);
1073 
1074 	pci_pm_set_unknown_state(pci_dev);
1075 
1076 	return 0;
1077 }
1078 
pci_pm_thaw_noirq(struct device * dev)1079 static int pci_pm_thaw_noirq(struct device *dev)
1080 {
1081 	struct pci_dev *pci_dev = to_pci_dev(dev);
1082 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1083 
1084 	/*
1085 	 * The pm->thaw_noirq() callback assumes the device has been
1086 	 * returned to D0 and its config state has been restored.
1087 	 *
1088 	 * In addition, pci_restore_state() restores MSI-X state in MMIO
1089 	 * space, which requires the device to be in D0, so return it to D0
1090 	 * in case the driver's "freeze" callbacks put it into a low-power
1091 	 * state.
1092 	 */
1093 	pci_pm_power_up_and_verify_state(pci_dev);
1094 	pci_restore_state(pci_dev);
1095 
1096 	if (pci_has_legacy_pm_support(pci_dev))
1097 		return 0;
1098 
1099 	if (pm && pm->thaw_noirq)
1100 		return pm->thaw_noirq(dev);
1101 
1102 	return 0;
1103 }
1104 
pci_pm_thaw(struct device * dev)1105 static int pci_pm_thaw(struct device *dev)
1106 {
1107 	struct pci_dev *pci_dev = to_pci_dev(dev);
1108 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1109 	int error = 0;
1110 
1111 	if (pci_has_legacy_pm_support(pci_dev))
1112 		return pci_legacy_resume(dev);
1113 
1114 	if (pm) {
1115 		if (pm->thaw)
1116 			error = pm->thaw(dev);
1117 	} else {
1118 		pci_pm_reenable_device(pci_dev);
1119 	}
1120 
1121 	pci_dev->state_saved = false;
1122 
1123 	return error;
1124 }
1125 
pci_pm_poweroff(struct device * dev)1126 static int pci_pm_poweroff(struct device *dev)
1127 {
1128 	struct pci_dev *pci_dev = to_pci_dev(dev);
1129 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1130 
1131 	if (pci_has_legacy_pm_support(pci_dev))
1132 		return pci_legacy_suspend(dev, PMSG_HIBERNATE);
1133 
1134 	if (!pm) {
1135 		pci_pm_default_suspend(pci_dev);
1136 		return 0;
1137 	}
1138 
1139 	/* The reason to do that is the same as in pci_pm_suspend(). */
1140 	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1141 	    pci_dev_need_resume(pci_dev)) {
1142 		pm_runtime_resume(dev);
1143 		pci_dev->state_saved = false;
1144 	} else {
1145 		pci_dev_adjust_pme(pci_dev);
1146 	}
1147 
1148 	if (pm->poweroff) {
1149 		int error;
1150 
1151 		error = pm->poweroff(dev);
1152 		suspend_report_result(dev, pm->poweroff, error);
1153 		if (error)
1154 			return error;
1155 	}
1156 
1157 	return 0;
1158 }
1159 
pci_pm_poweroff_late(struct device * dev)1160 static int pci_pm_poweroff_late(struct device *dev)
1161 {
1162 	if (dev_pm_skip_suspend(dev))
1163 		return 0;
1164 
1165 	pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));
1166 
1167 	return pm_generic_poweroff_late(dev);
1168 }
1169 
pci_pm_poweroff_noirq(struct device * dev)1170 static int pci_pm_poweroff_noirq(struct device *dev)
1171 {
1172 	struct pci_dev *pci_dev = to_pci_dev(dev);
1173 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1174 
1175 	if (dev_pm_skip_suspend(dev))
1176 		return 0;
1177 
1178 	if (pci_has_legacy_pm_support(pci_dev))
1179 		return pci_legacy_suspend_late(dev, PMSG_HIBERNATE);
1180 
1181 	if (!pm) {
1182 		pci_fixup_device(pci_fixup_suspend_late, pci_dev);
1183 		return 0;
1184 	}
1185 
1186 	if (pm->poweroff_noirq) {
1187 		int error;
1188 
1189 		error = pm->poweroff_noirq(dev);
1190 		suspend_report_result(dev, pm->poweroff_noirq, error);
1191 		if (error)
1192 			return error;
1193 	}
1194 
1195 	if (!pci_dev->state_saved && !pci_has_subordinate(pci_dev))
1196 		pci_prepare_to_sleep(pci_dev);
1197 
1198 	/*
1199 	 * The reason for doing this here is the same as for the analogous code
1200 	 * in pci_pm_suspend_noirq().
1201 	 */
1202 	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
1203 		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
1204 
1205 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
1206 
1207 	return 0;
1208 }
1209 
pci_pm_restore_noirq(struct device * dev)1210 static int pci_pm_restore_noirq(struct device *dev)
1211 {
1212 	struct pci_dev *pci_dev = to_pci_dev(dev);
1213 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1214 
1215 	pci_pm_default_resume_early(pci_dev);
1216 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
1217 
1218 	if (pci_has_legacy_pm_support(pci_dev))
1219 		return 0;
1220 
1221 	if (pm && pm->restore_noirq)
1222 		return pm->restore_noirq(dev);
1223 
1224 	return 0;
1225 }
1226 
pci_pm_restore(struct device * dev)1227 static int pci_pm_restore(struct device *dev)
1228 {
1229 	struct pci_dev *pci_dev = to_pci_dev(dev);
1230 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1231 
1232 	/*
1233 	 * This is necessary for the hibernation error path in which restore is
1234 	 * called without restoring the standard config registers of the device.
1235 	 */
1236 	if (pci_dev->state_saved)
1237 		pci_restore_standard_config(pci_dev);
1238 
1239 	if (pci_has_legacy_pm_support(pci_dev))
1240 		return pci_legacy_resume(dev);
1241 
1242 	pci_pm_default_resume(pci_dev);
1243 
1244 	if (pm) {
1245 		if (pm->restore)
1246 			return pm->restore(dev);
1247 	} else {
1248 		pci_pm_reenable_device(pci_dev);
1249 	}
1250 
1251 	return 0;
1252 }
1253 
1254 #else /* !CONFIG_HIBERNATE_CALLBACKS */
1255 
1256 #define pci_pm_freeze		NULL
1257 #define pci_pm_freeze_noirq	NULL
1258 #define pci_pm_thaw		NULL
1259 #define pci_pm_thaw_noirq	NULL
1260 #define pci_pm_poweroff		NULL
1261 #define pci_pm_poweroff_late	NULL
1262 #define pci_pm_poweroff_noirq	NULL
1263 #define pci_pm_restore		NULL
1264 #define pci_pm_restore_noirq	NULL
1265 
1266 #endif /* !CONFIG_HIBERNATE_CALLBACKS */
1267 
1268 #ifdef CONFIG_PM
1269 
pci_pm_runtime_suspend(struct device * dev)1270 static int pci_pm_runtime_suspend(struct device *dev)
1271 {
1272 	struct pci_dev *pci_dev = to_pci_dev(dev);
1273 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1274 	pci_power_t prev = pci_dev->current_state;
1275 	int error;
1276 
1277 	/*
1278 	 * If pci_dev->driver is not set (unbound), we leave the device in D0,
1279 	 * but it may go to D3cold when the bridge above it runtime suspends.
1280 	 * Save its config space in case that happens.
1281 	 */
1282 	if (!pci_dev->driver) {
1283 		pci_save_state(pci_dev);
1284 		return 0;
1285 	}
1286 
1287 	pci_dev->state_saved = false;
1288 	if (pm && pm->runtime_suspend) {
1289 		error = pm->runtime_suspend(dev);
1290 		/*
1291 		 * -EBUSY and -EAGAIN is used to request the runtime PM core
1292 		 * to schedule a new suspend, so log the event only with debug
1293 		 * log level.
1294 		 */
1295 		if (error == -EBUSY || error == -EAGAIN) {
1296 			pci_dbg(pci_dev, "can't suspend now (%ps returned %d)\n",
1297 				pm->runtime_suspend, error);
1298 			return error;
1299 		} else if (error) {
1300 			pci_err(pci_dev, "can't suspend (%ps returned %d)\n",
1301 				pm->runtime_suspend, error);
1302 			return error;
1303 		}
1304 	}
1305 
1306 	pci_fixup_device(pci_fixup_suspend, pci_dev);
1307 
1308 	if (pm && pm->runtime_suspend
1309 	    && !pci_dev->state_saved && pci_dev->current_state != PCI_D0
1310 	    && pci_dev->current_state != PCI_UNKNOWN) {
1311 		pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
1312 			      "PCI PM: State of device not saved by %pS\n",
1313 			      pm->runtime_suspend);
1314 		return 0;
1315 	}
1316 
1317 	if (!pci_dev->state_saved) {
1318 		pci_save_state(pci_dev);
1319 		pci_finish_runtime_suspend(pci_dev);
1320 	}
1321 
1322 	return 0;
1323 }
1324 
pci_pm_runtime_resume(struct device * dev)1325 static int pci_pm_runtime_resume(struct device *dev)
1326 {
1327 	struct pci_dev *pci_dev = to_pci_dev(dev);
1328 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1329 	pci_power_t prev_state = pci_dev->current_state;
1330 	int error = 0;
1331 
1332 	/*
1333 	 * Restoring config space is necessary even if the device is not bound
1334 	 * to a driver because although we left it in D0, it may have gone to
1335 	 * D3cold when the bridge above it runtime suspended.
1336 	 */
1337 	pci_pm_default_resume_early(pci_dev);
1338 
1339 	if (!pci_dev->driver)
1340 		return 0;
1341 
1342 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
1343 	pci_pm_default_resume(pci_dev);
1344 
1345 	if (prev_state == PCI_D3cold)
1346 		pci_pm_bridge_power_up_actions(pci_dev);
1347 
1348 	if (pm && pm->runtime_resume)
1349 		error = pm->runtime_resume(dev);
1350 
1351 	return error;
1352 }
1353 
pci_pm_runtime_idle(struct device * dev)1354 static int pci_pm_runtime_idle(struct device *dev)
1355 {
1356 	struct pci_dev *pci_dev = to_pci_dev(dev);
1357 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1358 
1359 	/*
1360 	 * If pci_dev->driver is not set (unbound), the device should
1361 	 * always remain in D0 regardless of the runtime PM status
1362 	 */
1363 	if (!pci_dev->driver)
1364 		return 0;
1365 
1366 	if (!pm)
1367 		return -ENOSYS;
1368 
1369 	if (pm->runtime_idle)
1370 		return pm->runtime_idle(dev);
1371 
1372 	return 0;
1373 }
1374 
1375 static const struct dev_pm_ops pci_dev_pm_ops = {
1376 	.prepare = pci_pm_prepare,
1377 	.complete = pci_pm_complete,
1378 	.suspend = pci_pm_suspend,
1379 	.suspend_late = pci_pm_suspend_late,
1380 	.resume = pci_pm_resume,
1381 	.resume_early = pci_pm_resume_early,
1382 	.freeze = pci_pm_freeze,
1383 	.thaw = pci_pm_thaw,
1384 	.poweroff = pci_pm_poweroff,
1385 	.poweroff_late = pci_pm_poweroff_late,
1386 	.restore = pci_pm_restore,
1387 	.suspend_noirq = pci_pm_suspend_noirq,
1388 	.resume_noirq = pci_pm_resume_noirq,
1389 	.freeze_noirq = pci_pm_freeze_noirq,
1390 	.thaw_noirq = pci_pm_thaw_noirq,
1391 	.poweroff_noirq = pci_pm_poweroff_noirq,
1392 	.restore_noirq = pci_pm_restore_noirq,
1393 	.runtime_suspend = pci_pm_runtime_suspend,
1394 	.runtime_resume = pci_pm_runtime_resume,
1395 	.runtime_idle = pci_pm_runtime_idle,
1396 };
1397 
1398 #define PCI_PM_OPS_PTR	(&pci_dev_pm_ops)
1399 
1400 #else /* !CONFIG_PM */
1401 
1402 #define pci_pm_runtime_suspend	NULL
1403 #define pci_pm_runtime_resume	NULL
1404 #define pci_pm_runtime_idle	NULL
1405 
1406 #define PCI_PM_OPS_PTR	NULL
1407 
1408 #endif /* !CONFIG_PM */
1409 
1410 /**
1411  * __pci_register_driver - register a new pci driver
1412  * @drv: the driver structure to register
1413  * @owner: owner module of drv
1414  * @mod_name: module name string
1415  *
1416  * Adds the driver structure to the list of registered drivers.
1417  * Returns a negative value on error, otherwise 0.
1418  * If no error occurred, the driver remains registered even if
1419  * no device was claimed during registration.
1420  */
__pci_register_driver(struct pci_driver * drv,struct module * owner,const char * mod_name)1421 int __pci_register_driver(struct pci_driver *drv, struct module *owner,
1422 			  const char *mod_name)
1423 {
1424 	/* initialize common driver fields */
1425 	drv->driver.name = drv->name;
1426 	drv->driver.bus = &pci_bus_type;
1427 	drv->driver.owner = owner;
1428 	drv->driver.mod_name = mod_name;
1429 	drv->driver.groups = drv->groups;
1430 	drv->driver.dev_groups = drv->dev_groups;
1431 
1432 	spin_lock_init(&drv->dynids.lock);
1433 	INIT_LIST_HEAD(&drv->dynids.list);
1434 
1435 	/* register with core */
1436 	return driver_register(&drv->driver);
1437 }
1438 EXPORT_SYMBOL(__pci_register_driver);
1439 
1440 /**
1441  * pci_unregister_driver - unregister a pci driver
1442  * @drv: the driver structure to unregister
1443  *
1444  * Deletes the driver structure from the list of registered PCI drivers,
1445  * gives it a chance to clean up by calling its remove() function for
1446  * each device it was responsible for, and marks those devices as
1447  * driverless.
1448  */
1449 
pci_unregister_driver(struct pci_driver * drv)1450 void pci_unregister_driver(struct pci_driver *drv)
1451 {
1452 	driver_unregister(&drv->driver);
1453 	pci_free_dynids(drv);
1454 }
1455 EXPORT_SYMBOL(pci_unregister_driver);
1456 
1457 static struct pci_driver pci_compat_driver = {
1458 	.name = "compat"
1459 };
1460 
1461 /**
1462  * pci_dev_driver - get the pci_driver of a device
1463  * @dev: the device to query
1464  *
1465  * Returns the appropriate pci_driver structure or %NULL if there is no
1466  * registered driver for the device.
1467  */
pci_dev_driver(const struct pci_dev * dev)1468 struct pci_driver *pci_dev_driver(const struct pci_dev *dev)
1469 {
1470 	if (dev->driver)
1471 		return dev->driver;
1472 	else {
1473 		int i;
1474 		for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1475 			if (dev->resource[i].flags & IORESOURCE_BUSY)
1476 				return &pci_compat_driver;
1477 	}
1478 	return NULL;
1479 }
1480 EXPORT_SYMBOL(pci_dev_driver);
1481 
1482 /**
1483  * pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure
1484  * @dev: the PCI device structure to match against
1485  * @drv: the device driver to search for matching PCI device id structures
1486  *
1487  * Used by a driver to check whether a PCI device present in the
1488  * system is in its list of supported devices. Returns the matching
1489  * pci_device_id structure or %NULL if there is no match.
1490  */
pci_bus_match(struct device * dev,struct device_driver * drv)1491 static int pci_bus_match(struct device *dev, struct device_driver *drv)
1492 {
1493 	struct pci_dev *pci_dev = to_pci_dev(dev);
1494 	struct pci_driver *pci_drv;
1495 	const struct pci_device_id *found_id;
1496 
1497 	if (!pci_dev->match_driver)
1498 		return 0;
1499 
1500 	pci_drv = to_pci_driver(drv);
1501 	found_id = pci_match_device(pci_drv, pci_dev);
1502 	if (found_id)
1503 		return 1;
1504 
1505 	return 0;
1506 }
1507 
1508 /**
1509  * pci_dev_get - increments the reference count of the pci device structure
1510  * @dev: the device being referenced
1511  *
1512  * Each live reference to a device should be refcounted.
1513  *
1514  * Drivers for PCI devices should normally record such references in
1515  * their probe() methods, when they bind to a device, and release
1516  * them by calling pci_dev_put(), in their disconnect() methods.
1517  *
1518  * A pointer to the device with the incremented reference counter is returned.
1519  */
pci_dev_get(struct pci_dev * dev)1520 struct pci_dev *pci_dev_get(struct pci_dev *dev)
1521 {
1522 	if (dev)
1523 		get_device(&dev->dev);
1524 	return dev;
1525 }
1526 EXPORT_SYMBOL(pci_dev_get);
1527 
1528 /**
1529  * pci_dev_put - release a use of the pci device structure
1530  * @dev: device that's been disconnected
1531  *
1532  * Must be called when a user of a device is finished with it.  When the last
1533  * user of the device calls this function, the memory of the device is freed.
1534  */
pci_dev_put(struct pci_dev * dev)1535 void pci_dev_put(struct pci_dev *dev)
1536 {
1537 	if (dev)
1538 		put_device(&dev->dev);
1539 }
1540 EXPORT_SYMBOL(pci_dev_put);
1541 
pci_uevent(struct device * dev,struct kobj_uevent_env * env)1542 static int pci_uevent(struct device *dev, struct kobj_uevent_env *env)
1543 {
1544 	struct pci_dev *pdev;
1545 
1546 	if (!dev)
1547 		return -ENODEV;
1548 
1549 	pdev = to_pci_dev(dev);
1550 
1551 	if (add_uevent_var(env, "PCI_CLASS=%04X", pdev->class))
1552 		return -ENOMEM;
1553 
1554 	if (add_uevent_var(env, "PCI_ID=%04X:%04X", pdev->vendor, pdev->device))
1555 		return -ENOMEM;
1556 
1557 	if (add_uevent_var(env, "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,
1558 			   pdev->subsystem_device))
1559 		return -ENOMEM;
1560 
1561 	if (add_uevent_var(env, "PCI_SLOT_NAME=%s", pci_name(pdev)))
1562 		return -ENOMEM;
1563 
1564 	if (add_uevent_var(env, "MODALIAS=pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X",
1565 			   pdev->vendor, pdev->device,
1566 			   pdev->subsystem_vendor, pdev->subsystem_device,
1567 			   (u8)(pdev->class >> 16), (u8)(pdev->class >> 8),
1568 			   (u8)(pdev->class)))
1569 		return -ENOMEM;
1570 
1571 	return 0;
1572 }
1573 
1574 #if defined(CONFIG_PCIEAER) || defined(CONFIG_EEH)
1575 /**
1576  * pci_uevent_ers - emit a uevent during recovery path of PCI device
1577  * @pdev: PCI device undergoing error recovery
1578  * @err_type: type of error event
1579  */
pci_uevent_ers(struct pci_dev * pdev,enum pci_ers_result err_type)1580 void pci_uevent_ers(struct pci_dev *pdev, enum pci_ers_result err_type)
1581 {
1582 	int idx = 0;
1583 	char *envp[3];
1584 
1585 	switch (err_type) {
1586 	case PCI_ERS_RESULT_NONE:
1587 	case PCI_ERS_RESULT_CAN_RECOVER:
1588 		envp[idx++] = "ERROR_EVENT=BEGIN_RECOVERY";
1589 		envp[idx++] = "DEVICE_ONLINE=0";
1590 		break;
1591 	case PCI_ERS_RESULT_RECOVERED:
1592 		envp[idx++] = "ERROR_EVENT=SUCCESSFUL_RECOVERY";
1593 		envp[idx++] = "DEVICE_ONLINE=1";
1594 		break;
1595 	case PCI_ERS_RESULT_DISCONNECT:
1596 		envp[idx++] = "ERROR_EVENT=FAILED_RECOVERY";
1597 		envp[idx++] = "DEVICE_ONLINE=0";
1598 		break;
1599 	default:
1600 		break;
1601 	}
1602 
1603 	if (idx > 0) {
1604 		envp[idx++] = NULL;
1605 		kobject_uevent_env(&pdev->dev.kobj, KOBJ_CHANGE, envp);
1606 	}
1607 }
1608 #endif
1609 
pci_bus_num_vf(struct device * dev)1610 static int pci_bus_num_vf(struct device *dev)
1611 {
1612 	return pci_num_vf(to_pci_dev(dev));
1613 }
1614 
1615 /**
1616  * pci_dma_configure - Setup DMA configuration
1617  * @dev: ptr to dev structure
1618  *
1619  * Function to update PCI devices's DMA configuration using the same
1620  * info from the OF node or ACPI node of host bridge's parent (if any).
1621  */
pci_dma_configure(struct device * dev)1622 static int pci_dma_configure(struct device *dev)
1623 {
1624 	struct pci_driver *driver = to_pci_driver(dev->driver);
1625 	struct device *bridge;
1626 	int ret = 0;
1627 
1628 	bridge = pci_get_host_bridge_device(to_pci_dev(dev));
1629 
1630 	if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
1631 	    bridge->parent->of_node) {
1632 		ret = of_dma_configure(dev, bridge->parent->of_node, true);
1633 	} else if (has_acpi_companion(bridge)) {
1634 		struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
1635 
1636 		ret = acpi_dma_configure(dev, acpi_get_dma_attr(adev));
1637 	}
1638 
1639 	pci_put_host_bridge_device(bridge);
1640 
1641 	if (!ret && !driver->driver_managed_dma) {
1642 		ret = iommu_device_use_default_domain(dev);
1643 		if (ret)
1644 			arch_teardown_dma_ops(dev);
1645 	}
1646 
1647 	return ret;
1648 }
1649 
pci_dma_cleanup(struct device * dev)1650 static void pci_dma_cleanup(struct device *dev)
1651 {
1652 	struct pci_driver *driver = to_pci_driver(dev->driver);
1653 
1654 	if (!driver->driver_managed_dma)
1655 		iommu_device_unuse_default_domain(dev);
1656 }
1657 
1658 struct bus_type pci_bus_type = {
1659 	.name		= "pci",
1660 	.match		= pci_bus_match,
1661 	.uevent		= pci_uevent,
1662 	.probe		= pci_device_probe,
1663 	.remove		= pci_device_remove,
1664 	.shutdown	= pci_device_shutdown,
1665 	.dev_groups	= pci_dev_groups,
1666 	.bus_groups	= pci_bus_groups,
1667 	.drv_groups	= pci_drv_groups,
1668 	.pm		= PCI_PM_OPS_PTR,
1669 	.num_vf		= pci_bus_num_vf,
1670 	.dma_configure	= pci_dma_configure,
1671 	.dma_cleanup	= pci_dma_cleanup,
1672 };
1673 EXPORT_SYMBOL(pci_bus_type);
1674 
1675 #ifdef CONFIG_PCIEPORTBUS
pcie_port_bus_match(struct device * dev,struct device_driver * drv)1676 static int pcie_port_bus_match(struct device *dev, struct device_driver *drv)
1677 {
1678 	struct pcie_device *pciedev;
1679 	struct pcie_port_service_driver *driver;
1680 
1681 	if (drv->bus != &pcie_port_bus_type || dev->bus != &pcie_port_bus_type)
1682 		return 0;
1683 
1684 	pciedev = to_pcie_device(dev);
1685 	driver = to_service_driver(drv);
1686 
1687 	if (driver->service != pciedev->service)
1688 		return 0;
1689 
1690 	if (driver->port_type != PCIE_ANY_PORT &&
1691 	    driver->port_type != pci_pcie_type(pciedev->port))
1692 		return 0;
1693 
1694 	return 1;
1695 }
1696 
1697 struct bus_type pcie_port_bus_type = {
1698 	.name		= "pci_express",
1699 	.match		= pcie_port_bus_match,
1700 };
1701 EXPORT_SYMBOL_GPL(pcie_port_bus_type);
1702 #endif
1703 
pci_driver_init(void)1704 static int __init pci_driver_init(void)
1705 {
1706 	int ret;
1707 
1708 	ret = bus_register(&pci_bus_type);
1709 	if (ret)
1710 		return ret;
1711 
1712 #ifdef CONFIG_PCIEPORTBUS
1713 	ret = bus_register(&pcie_port_bus_type);
1714 	if (ret)
1715 		return ret;
1716 #endif
1717 	dma_debug_add_bus(&pci_bus_type);
1718 	return 0;
1719 }
1720 postcore_initcall(pci_driver_init);
1721