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->remove) {
448 		pm_runtime_get_sync(dev);
449 		/*
450 		 * If the driver provides a .runtime_idle() callback and it has
451 		 * started to run already, it may continue to run in parallel
452 		 * with the code below, so wait until all of the runtime PM
453 		 * activity has completed.
454 		 */
455 		pm_runtime_barrier(dev);
456 		drv->remove(pci_dev);
457 		pm_runtime_put_noidle(dev);
458 	}
459 	pcibios_free_irq(pci_dev);
460 	pci_dev->driver = NULL;
461 	pci_iov_remove(pci_dev);
462 
463 	/* Undo the runtime PM settings in local_pci_probe() */
464 	pm_runtime_put_sync(dev);
465 
466 	/*
467 	 * If the device is still on, set the power state as "unknown",
468 	 * since it might change by the next time we load the driver.
469 	 */
470 	if (pci_dev->current_state == PCI_D0)
471 		pci_dev->current_state = PCI_UNKNOWN;
472 
473 	/*
474 	 * We would love to complain here if pci_dev->is_enabled is set, that
475 	 * the driver should have called pci_disable_device(), but the
476 	 * unfortunate fact is there are too many odd BIOS and bridge setups
477 	 * that don't like drivers doing that all of the time.
478 	 * Oh well, we can dream of sane hardware when we sleep, no matter how
479 	 * horrible the crap we have to deal with is when we are awake...
480 	 */
481 
482 	pci_dev_put(pci_dev);
483 	return 0;
484 }
485 
pci_device_shutdown(struct device *dev)486 static void pci_device_shutdown(struct device *dev)
487 {
488 	struct pci_dev *pci_dev = to_pci_dev(dev);
489 	struct pci_driver *drv = pci_dev->driver;
490 
491 	pm_runtime_resume(dev);
492 
493 	if (drv && drv->shutdown)
494 		drv->shutdown(pci_dev);
495 
496 	/*
497 	 * If this is a kexec reboot, turn off Bus Master bit on the
498 	 * device to tell it to not continue to do DMA. Don't touch
499 	 * devices in D3cold or unknown states.
500 	 * If it is not a kexec reboot, firmware will hit the PCI
501 	 * devices with big hammer and stop their DMA any way.
502 	 */
503 	if (kexec_in_progress && (pci_dev->current_state <= PCI_D3hot))
504 		pci_clear_master(pci_dev);
505 }
506 
507 #ifdef CONFIG_PM
508 
509 /* Auxiliary functions used for system resume and run-time resume. */
510 
511 /**
512  * pci_restore_standard_config - restore standard config registers of PCI device
513  * @pci_dev: PCI device to handle
514  */
pci_restore_standard_config(struct pci_dev *pci_dev)515 static int pci_restore_standard_config(struct pci_dev *pci_dev)
516 {
517 	pci_update_current_state(pci_dev, PCI_UNKNOWN);
518 
519 	if (pci_dev->current_state != PCI_D0) {
520 		int error = pci_set_power_state(pci_dev, PCI_D0);
521 		if (error)
522 			return error;
523 	}
524 
525 	pci_restore_state(pci_dev);
526 	pci_pme_restore(pci_dev);
527 	return 0;
528 }
529 
pci_pm_default_resume(struct pci_dev *pci_dev)530 static void pci_pm_default_resume(struct pci_dev *pci_dev)
531 {
532 	pci_fixup_device(pci_fixup_resume, pci_dev);
533 	pci_enable_wake(pci_dev, PCI_D0, false);
534 }
535 
536 #endif
537 
538 #ifdef CONFIG_PM_SLEEP
539 
pci_pm_default_resume_early(struct pci_dev *pci_dev)540 static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
541 {
542 	pci_power_up(pci_dev);
543 	pci_update_current_state(pci_dev, PCI_D0);
544 	pci_restore_state(pci_dev);
545 	pci_pme_restore(pci_dev);
546 }
547 
548 /*
549  * Default "suspend" method for devices that have no driver provided suspend,
550  * or not even a driver at all (second part).
551  */
pci_pm_set_unknown_state(struct pci_dev *pci_dev)552 static void pci_pm_set_unknown_state(struct pci_dev *pci_dev)
553 {
554 	/*
555 	 * mark its power state as "unknown", since we don't know if
556 	 * e.g. the BIOS will change its device state when we suspend.
557 	 */
558 	if (pci_dev->current_state == PCI_D0)
559 		pci_dev->current_state = PCI_UNKNOWN;
560 }
561 
562 /*
563  * Default "resume" method for devices that have no driver provided resume,
564  * or not even a driver at all (second part).
565  */
pci_pm_reenable_device(struct pci_dev *pci_dev)566 static int pci_pm_reenable_device(struct pci_dev *pci_dev)
567 {
568 	int retval;
569 
570 	/* if the device was enabled before suspend, reenable */
571 	retval = pci_reenable_device(pci_dev);
572 	/*
573 	 * if the device was busmaster before the suspend, make it busmaster
574 	 * again
575 	 */
576 	if (pci_dev->is_busmaster)
577 		pci_set_master(pci_dev);
578 
579 	return retval;
580 }
581 
pci_legacy_suspend(struct device *dev, pm_message_t state)582 static int pci_legacy_suspend(struct device *dev, pm_message_t state)
583 {
584 	struct pci_dev *pci_dev = to_pci_dev(dev);
585 	struct pci_driver *drv = pci_dev->driver;
586 
587 	if (drv && drv->suspend) {
588 		pci_power_t prev = pci_dev->current_state;
589 		int error;
590 
591 		error = drv->suspend(pci_dev, state);
592 		suspend_report_result(drv->suspend, error);
593 		if (error)
594 			return error;
595 
596 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
597 		    && pci_dev->current_state != PCI_UNKNOWN) {
598 			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
599 				      "PCI PM: Device state not saved by %pS\n",
600 				      drv->suspend);
601 		}
602 	}
603 
604 	pci_fixup_device(pci_fixup_suspend, pci_dev);
605 
606 	return 0;
607 }
608 
pci_legacy_suspend_late(struct device *dev, pm_message_t state)609 static int pci_legacy_suspend_late(struct device *dev, pm_message_t state)
610 {
611 	struct pci_dev *pci_dev = to_pci_dev(dev);
612 
613 	if (!pci_dev->state_saved)
614 		pci_save_state(pci_dev);
615 
616 	pci_pm_set_unknown_state(pci_dev);
617 
618 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
619 
620 	return 0;
621 }
622 
pci_legacy_resume(struct device *dev)623 static int pci_legacy_resume(struct device *dev)
624 {
625 	struct pci_dev *pci_dev = to_pci_dev(dev);
626 	struct pci_driver *drv = pci_dev->driver;
627 
628 	pci_fixup_device(pci_fixup_resume, pci_dev);
629 
630 	return drv && drv->resume ?
631 			drv->resume(pci_dev) : pci_pm_reenable_device(pci_dev);
632 }
633 
634 /* Auxiliary functions used by the new power management framework */
635 
pci_pm_default_suspend(struct pci_dev *pci_dev)636 static void pci_pm_default_suspend(struct pci_dev *pci_dev)
637 {
638 	/* Disable non-bridge devices without PM support */
639 	if (!pci_has_subordinate(pci_dev))
640 		pci_disable_enabled_device(pci_dev);
641 }
642 
pci_has_legacy_pm_support(struct pci_dev *pci_dev)643 static bool pci_has_legacy_pm_support(struct pci_dev *pci_dev)
644 {
645 	struct pci_driver *drv = pci_dev->driver;
646 	bool ret = drv && (drv->suspend || drv->resume);
647 
648 	/*
649 	 * Legacy PM support is used by default, so warn if the new framework is
650 	 * supported as well.  Drivers are supposed to support either the
651 	 * former, or the latter, but not both at the same time.
652 	 */
653 	pci_WARN(pci_dev, ret && drv->driver.pm, "device %04x:%04x\n",
654 		 pci_dev->vendor, pci_dev->device);
655 
656 	return ret;
657 }
658 
659 /* New power management framework */
660 
pci_pm_prepare(struct device *dev)661 static int pci_pm_prepare(struct device *dev)
662 {
663 	struct pci_dev *pci_dev = to_pci_dev(dev);
664 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
665 
666 	if (pm && pm->prepare) {
667 		int error = pm->prepare(dev);
668 		if (error < 0)
669 			return error;
670 
671 		if (!error && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
672 			return 0;
673 	}
674 	if (pci_dev_need_resume(pci_dev))
675 		return 0;
676 
677 	/*
678 	 * The PME setting needs to be adjusted here in case the direct-complete
679 	 * optimization is used with respect to this device.
680 	 */
681 	pci_dev_adjust_pme(pci_dev);
682 	return 1;
683 }
684 
pci_pm_complete(struct device *dev)685 static void pci_pm_complete(struct device *dev)
686 {
687 	struct pci_dev *pci_dev = to_pci_dev(dev);
688 
689 	pci_dev_complete_resume(pci_dev);
690 	pm_generic_complete(dev);
691 
692 	/* Resume device if platform firmware has put it in reset-power-on */
693 	if (pm_runtime_suspended(dev) && pm_resume_via_firmware()) {
694 		pci_power_t pre_sleep_state = pci_dev->current_state;
695 
696 		pci_refresh_power_state(pci_dev);
697 		/*
698 		 * On platforms with ACPI this check may also trigger for
699 		 * devices sharing power resources if one of those power
700 		 * resources has been activated as a result of a change of the
701 		 * power state of another device sharing it.  However, in that
702 		 * case it is also better to resume the device, in general.
703 		 */
704 		if (pci_dev->current_state < pre_sleep_state)
705 			pm_request_resume(dev);
706 	}
707 }
708 
709 #else /* !CONFIG_PM_SLEEP */
710 
711 #define pci_pm_prepare	NULL
712 #define pci_pm_complete	NULL
713 
714 #endif /* !CONFIG_PM_SLEEP */
715 
716 #ifdef CONFIG_SUSPEND
pcie_pme_root_status_cleanup(struct pci_dev *pci_dev)717 static void pcie_pme_root_status_cleanup(struct pci_dev *pci_dev)
718 {
719 	/*
720 	 * Some BIOSes forget to clear Root PME Status bits after system
721 	 * wakeup, which breaks ACPI-based runtime wakeup on PCI Express.
722 	 * Clear those bits now just in case (shouldn't hurt).
723 	 */
724 	if (pci_is_pcie(pci_dev) &&
725 	    (pci_pcie_type(pci_dev) == PCI_EXP_TYPE_ROOT_PORT ||
726 	     pci_pcie_type(pci_dev) == PCI_EXP_TYPE_RC_EC))
727 		pcie_clear_root_pme_status(pci_dev);
728 }
729 
pci_pm_suspend(struct device *dev)730 static int pci_pm_suspend(struct device *dev)
731 {
732 	struct pci_dev *pci_dev = to_pci_dev(dev);
733 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
734 
735 	pci_dev->skip_bus_pm = false;
736 
737 	if (pci_has_legacy_pm_support(pci_dev))
738 		return pci_legacy_suspend(dev, PMSG_SUSPEND);
739 
740 	if (!pm) {
741 		pci_pm_default_suspend(pci_dev);
742 		return 0;
743 	}
744 
745 	/*
746 	 * PCI devices suspended at run time may need to be resumed at this
747 	 * point, because in general it may be necessary to reconfigure them for
748 	 * system suspend.  Namely, if the device is expected to wake up the
749 	 * system from the sleep state, it may have to be reconfigured for this
750 	 * purpose, or if the device is not expected to wake up the system from
751 	 * the sleep state, it should be prevented from signaling wakeup events
752 	 * going forward.
753 	 *
754 	 * Also if the driver of the device does not indicate that its system
755 	 * suspend callbacks can cope with runtime-suspended devices, it is
756 	 * better to resume the device from runtime suspend here.
757 	 */
758 	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
759 	    pci_dev_need_resume(pci_dev)) {
760 		pm_runtime_resume(dev);
761 		pci_dev->state_saved = false;
762 	} else {
763 		pci_dev_adjust_pme(pci_dev);
764 	}
765 
766 	if (pm->suspend) {
767 		pci_power_t prev = pci_dev->current_state;
768 		int error;
769 
770 		error = pm->suspend(dev);
771 		suspend_report_result(pm->suspend, error);
772 		if (error)
773 			return error;
774 
775 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
776 		    && pci_dev->current_state != PCI_UNKNOWN) {
777 			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
778 				      "PCI PM: State of device not saved by %pS\n",
779 				      pm->suspend);
780 		}
781 	}
782 
783 	return 0;
784 }
785 
pci_pm_suspend_late(struct device *dev)786 static int pci_pm_suspend_late(struct device *dev)
787 {
788 	if (dev_pm_skip_suspend(dev))
789 		return 0;
790 
791 	pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));
792 
793 	return pm_generic_suspend_late(dev);
794 }
795 
pci_pm_suspend_noirq(struct device *dev)796 static int pci_pm_suspend_noirq(struct device *dev)
797 {
798 	struct pci_dev *pci_dev = to_pci_dev(dev);
799 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
800 
801 	if (dev_pm_skip_suspend(dev))
802 		return 0;
803 
804 	if (pci_has_legacy_pm_support(pci_dev))
805 		return pci_legacy_suspend_late(dev, PMSG_SUSPEND);
806 
807 	if (!pm) {
808 		pci_save_state(pci_dev);
809 		goto Fixup;
810 	}
811 
812 	if (pm->suspend_noirq) {
813 		pci_power_t prev = pci_dev->current_state;
814 		int error;
815 
816 		error = pm->suspend_noirq(dev);
817 		suspend_report_result(pm->suspend_noirq, error);
818 		if (error)
819 			return error;
820 
821 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
822 		    && pci_dev->current_state != PCI_UNKNOWN) {
823 			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
824 				      "PCI PM: State of device not saved by %pS\n",
825 				      pm->suspend_noirq);
826 			goto Fixup;
827 		}
828 	}
829 
830 	if (pci_dev->skip_bus_pm) {
831 		/*
832 		 * Either the device is a bridge with a child in D0 below it, or
833 		 * the function is running for the second time in a row without
834 		 * going through full resume, which is possible only during
835 		 * suspend-to-idle in a spurious wakeup case.  The device should
836 		 * be in D0 at this point, but if it is a bridge, it may be
837 		 * necessary to save its state.
838 		 */
839 		if (!pci_dev->state_saved)
840 			pci_save_state(pci_dev);
841 	} else if (!pci_dev->state_saved) {
842 		pci_save_state(pci_dev);
843 		if (pci_power_manageable(pci_dev))
844 			pci_prepare_to_sleep(pci_dev);
845 	}
846 
847 	pci_dbg(pci_dev, "PCI PM: Suspend power state: %s\n",
848 		pci_power_name(pci_dev->current_state));
849 
850 	if (pci_dev->current_state == PCI_D0) {
851 		pci_dev->skip_bus_pm = true;
852 		/*
853 		 * Per PCI PM r1.2, table 6-1, a bridge must be in D0 if any
854 		 * downstream device is in D0, so avoid changing the power state
855 		 * of the parent bridge by setting the skip_bus_pm flag for it.
856 		 */
857 		if (pci_dev->bus->self)
858 			pci_dev->bus->self->skip_bus_pm = true;
859 	}
860 
861 	if (pci_dev->skip_bus_pm && pm_suspend_no_platform()) {
862 		pci_dbg(pci_dev, "PCI PM: Skipped\n");
863 		goto Fixup;
864 	}
865 
866 	pci_pm_set_unknown_state(pci_dev);
867 
868 	/*
869 	 * Some BIOSes from ASUS have a bug: If a USB EHCI host controller's
870 	 * PCI COMMAND register isn't 0, the BIOS assumes that the controller
871 	 * hasn't been quiesced and tries to turn it off.  If the controller
872 	 * is already in D3, this can hang or cause memory corruption.
873 	 *
874 	 * Since the value of the COMMAND register doesn't matter once the
875 	 * device has been suspended, we can safely set it to 0 here.
876 	 */
877 	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
878 		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
879 
880 Fixup:
881 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
882 
883 	/*
884 	 * If the target system sleep state is suspend-to-idle, it is sufficient
885 	 * to check whether or not the device's wakeup settings are good for
886 	 * runtime PM.  Otherwise, the pm_resume_via_firmware() check will cause
887 	 * pci_pm_complete() to take care of fixing up the device's state
888 	 * anyway, if need be.
889 	 */
890 	if (device_can_wakeup(dev) && !device_may_wakeup(dev))
891 		dev->power.may_skip_resume = false;
892 
893 	return 0;
894 }
895 
pci_pm_resume_noirq(struct device *dev)896 static int pci_pm_resume_noirq(struct device *dev)
897 {
898 	struct pci_dev *pci_dev = to_pci_dev(dev);
899 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
900 	pci_power_t prev_state = pci_dev->current_state;
901 	bool skip_bus_pm = pci_dev->skip_bus_pm;
902 
903 	if (dev_pm_skip_resume(dev))
904 		return 0;
905 
906 	/*
907 	 * In the suspend-to-idle case, devices left in D0 during suspend will
908 	 * stay in D0, so it is not necessary to restore or update their
909 	 * configuration here and attempting to put them into D0 again is
910 	 * pointless, so avoid doing that.
911 	 */
912 	if (!(skip_bus_pm && pm_suspend_no_platform()))
913 		pci_pm_default_resume_early(pci_dev);
914 
915 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
916 	pcie_pme_root_status_cleanup(pci_dev);
917 
918 	if (!skip_bus_pm && prev_state == PCI_D3cold)
919 		pci_bridge_wait_for_secondary_bus(pci_dev, "resume", PCI_RESET_WAIT);
920 
921 	if (pci_has_legacy_pm_support(pci_dev))
922 		return 0;
923 
924 	if (pm && pm->resume_noirq)
925 		return pm->resume_noirq(dev);
926 
927 	return 0;
928 }
929 
pci_pm_resume_early(struct device *dev)930 static int pci_pm_resume_early(struct device *dev)
931 {
932 	if (dev_pm_skip_resume(dev))
933 		return 0;
934 
935 	return pm_generic_resume_early(dev);
936 }
937 
pci_pm_resume(struct device *dev)938 static int pci_pm_resume(struct device *dev)
939 {
940 	struct pci_dev *pci_dev = to_pci_dev(dev);
941 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
942 
943 	/*
944 	 * This is necessary for the suspend error path in which resume is
945 	 * called without restoring the standard config registers of the device.
946 	 */
947 	if (pci_dev->state_saved)
948 		pci_restore_standard_config(pci_dev);
949 
950 	if (pci_has_legacy_pm_support(pci_dev))
951 		return pci_legacy_resume(dev);
952 
953 	pci_pm_default_resume(pci_dev);
954 
955 	if (pm) {
956 		if (pm->resume)
957 			return pm->resume(dev);
958 	} else {
959 		pci_pm_reenable_device(pci_dev);
960 	}
961 
962 	return 0;
963 }
964 
965 #else /* !CONFIG_SUSPEND */
966 
967 #define pci_pm_suspend		NULL
968 #define pci_pm_suspend_late	NULL
969 #define pci_pm_suspend_noirq	NULL
970 #define pci_pm_resume		NULL
971 #define pci_pm_resume_early	NULL
972 #define pci_pm_resume_noirq	NULL
973 
974 #endif /* !CONFIG_SUSPEND */
975 
976 #ifdef CONFIG_HIBERNATE_CALLBACKS
977 
pci_pm_freeze(struct device *dev)978 static int pci_pm_freeze(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 	if (pci_has_legacy_pm_support(pci_dev))
984 		return pci_legacy_suspend(dev, PMSG_FREEZE);
985 
986 	if (!pm) {
987 		pci_pm_default_suspend(pci_dev);
988 		return 0;
989 	}
990 
991 	/*
992 	 * Resume all runtime-suspended devices before creating a snapshot
993 	 * image of system memory, because the restore kernel generally cannot
994 	 * be expected to always handle them consistently and they need to be
995 	 * put into the runtime-active metastate during system resume anyway,
996 	 * so it is better to ensure that the state saved in the image will be
997 	 * always consistent with that.
998 	 */
999 	pm_runtime_resume(dev);
1000 	pci_dev->state_saved = false;
1001 
1002 	if (pm->freeze) {
1003 		int error;
1004 
1005 		error = pm->freeze(dev);
1006 		suspend_report_result(pm->freeze, error);
1007 		if (error)
1008 			return error;
1009 	}
1010 
1011 	return 0;
1012 }
1013 
pci_pm_freeze_noirq(struct device *dev)1014 static int pci_pm_freeze_noirq(struct device *dev)
1015 {
1016 	struct pci_dev *pci_dev = to_pci_dev(dev);
1017 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1018 
1019 	if (pci_has_legacy_pm_support(pci_dev))
1020 		return pci_legacy_suspend_late(dev, PMSG_FREEZE);
1021 
1022 	if (pm && pm->freeze_noirq) {
1023 		int error;
1024 
1025 		error = pm->freeze_noirq(dev);
1026 		suspend_report_result(pm->freeze_noirq, error);
1027 		if (error)
1028 			return error;
1029 	}
1030 
1031 	if (!pci_dev->state_saved)
1032 		pci_save_state(pci_dev);
1033 
1034 	pci_pm_set_unknown_state(pci_dev);
1035 
1036 	return 0;
1037 }
1038 
pci_pm_thaw_noirq(struct device *dev)1039 static int pci_pm_thaw_noirq(struct device *dev)
1040 {
1041 	struct pci_dev *pci_dev = to_pci_dev(dev);
1042 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1043 
1044 	/*
1045 	 * The pm->thaw_noirq() callback assumes the device has been
1046 	 * returned to D0 and its config state has been restored.
1047 	 *
1048 	 * In addition, pci_restore_state() restores MSI-X state in MMIO
1049 	 * space, which requires the device to be in D0, so return it to D0
1050 	 * in case the driver's "freeze" callbacks put it into a low-power
1051 	 * state.
1052 	 */
1053 	pci_set_power_state(pci_dev, PCI_D0);
1054 	pci_restore_state(pci_dev);
1055 
1056 	if (pci_has_legacy_pm_support(pci_dev))
1057 		return 0;
1058 
1059 	if (pm && pm->thaw_noirq)
1060 		return pm->thaw_noirq(dev);
1061 
1062 	return 0;
1063 }
1064 
pci_pm_thaw(struct device *dev)1065 static int pci_pm_thaw(struct device *dev)
1066 {
1067 	struct pci_dev *pci_dev = to_pci_dev(dev);
1068 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1069 	int error = 0;
1070 
1071 	if (pci_has_legacy_pm_support(pci_dev))
1072 		return pci_legacy_resume(dev);
1073 
1074 	if (pm) {
1075 		if (pm->thaw)
1076 			error = pm->thaw(dev);
1077 	} else {
1078 		pci_pm_reenable_device(pci_dev);
1079 	}
1080 
1081 	pci_dev->state_saved = false;
1082 
1083 	return error;
1084 }
1085 
pci_pm_poweroff(struct device *dev)1086 static int pci_pm_poweroff(struct device *dev)
1087 {
1088 	struct pci_dev *pci_dev = to_pci_dev(dev);
1089 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1090 
1091 	if (pci_has_legacy_pm_support(pci_dev))
1092 		return pci_legacy_suspend(dev, PMSG_HIBERNATE);
1093 
1094 	if (!pm) {
1095 		pci_pm_default_suspend(pci_dev);
1096 		return 0;
1097 	}
1098 
1099 	/* The reason to do that is the same as in pci_pm_suspend(). */
1100 	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1101 	    pci_dev_need_resume(pci_dev)) {
1102 		pm_runtime_resume(dev);
1103 		pci_dev->state_saved = false;
1104 	} else {
1105 		pci_dev_adjust_pme(pci_dev);
1106 	}
1107 
1108 	if (pm->poweroff) {
1109 		int error;
1110 
1111 		error = pm->poweroff(dev);
1112 		suspend_report_result(pm->poweroff, error);
1113 		if (error)
1114 			return error;
1115 	}
1116 
1117 	return 0;
1118 }
1119 
pci_pm_poweroff_late(struct device *dev)1120 static int pci_pm_poweroff_late(struct device *dev)
1121 {
1122 	if (dev_pm_skip_suspend(dev))
1123 		return 0;
1124 
1125 	pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));
1126 
1127 	return pm_generic_poweroff_late(dev);
1128 }
1129 
pci_pm_poweroff_noirq(struct device *dev)1130 static int pci_pm_poweroff_noirq(struct device *dev)
1131 {
1132 	struct pci_dev *pci_dev = to_pci_dev(dev);
1133 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1134 
1135 	if (dev_pm_skip_suspend(dev))
1136 		return 0;
1137 
1138 	if (pci_has_legacy_pm_support(pci_dev))
1139 		return pci_legacy_suspend_late(dev, PMSG_HIBERNATE);
1140 
1141 	if (!pm) {
1142 		pci_fixup_device(pci_fixup_suspend_late, pci_dev);
1143 		return 0;
1144 	}
1145 
1146 	if (pm->poweroff_noirq) {
1147 		int error;
1148 
1149 		error = pm->poweroff_noirq(dev);
1150 		suspend_report_result(pm->poweroff_noirq, error);
1151 		if (error)
1152 			return error;
1153 	}
1154 
1155 	if (!pci_dev->state_saved && !pci_has_subordinate(pci_dev))
1156 		pci_prepare_to_sleep(pci_dev);
1157 
1158 	/*
1159 	 * The reason for doing this here is the same as for the analogous code
1160 	 * in pci_pm_suspend_noirq().
1161 	 */
1162 	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
1163 		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
1164 
1165 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
1166 
1167 	return 0;
1168 }
1169 
pci_pm_restore_noirq(struct device *dev)1170 static int pci_pm_restore_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 	pci_pm_default_resume_early(pci_dev);
1176 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
1177 
1178 	if (pci_has_legacy_pm_support(pci_dev))
1179 		return 0;
1180 
1181 	if (pm && pm->restore_noirq)
1182 		return pm->restore_noirq(dev);
1183 
1184 	return 0;
1185 }
1186 
pci_pm_restore(struct device *dev)1187 static int pci_pm_restore(struct device *dev)
1188 {
1189 	struct pci_dev *pci_dev = to_pci_dev(dev);
1190 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1191 
1192 	/*
1193 	 * This is necessary for the hibernation error path in which restore is
1194 	 * called without restoring the standard config registers of the device.
1195 	 */
1196 	if (pci_dev->state_saved)
1197 		pci_restore_standard_config(pci_dev);
1198 
1199 	if (pci_has_legacy_pm_support(pci_dev))
1200 		return pci_legacy_resume(dev);
1201 
1202 	pci_pm_default_resume(pci_dev);
1203 
1204 	if (pm) {
1205 		if (pm->restore)
1206 			return pm->restore(dev);
1207 	} else {
1208 		pci_pm_reenable_device(pci_dev);
1209 	}
1210 
1211 	return 0;
1212 }
1213 
1214 #else /* !CONFIG_HIBERNATE_CALLBACKS */
1215 
1216 #define pci_pm_freeze		NULL
1217 #define pci_pm_freeze_noirq	NULL
1218 #define pci_pm_thaw		NULL
1219 #define pci_pm_thaw_noirq	NULL
1220 #define pci_pm_poweroff		NULL
1221 #define pci_pm_poweroff_late	NULL
1222 #define pci_pm_poweroff_noirq	NULL
1223 #define pci_pm_restore		NULL
1224 #define pci_pm_restore_noirq	NULL
1225 
1226 #endif /* !CONFIG_HIBERNATE_CALLBACKS */
1227 
1228 #ifdef CONFIG_PM
1229 
pci_pm_runtime_suspend(struct device *dev)1230 static int pci_pm_runtime_suspend(struct device *dev)
1231 {
1232 	struct pci_dev *pci_dev = to_pci_dev(dev);
1233 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1234 	pci_power_t prev = pci_dev->current_state;
1235 	int error;
1236 
1237 	/*
1238 	 * If pci_dev->driver is not set (unbound), we leave the device in D0,
1239 	 * but it may go to D3cold when the bridge above it runtime suspends.
1240 	 * Save its config space in case that happens.
1241 	 */
1242 	if (!pci_dev->driver) {
1243 		pci_save_state(pci_dev);
1244 		return 0;
1245 	}
1246 
1247 	pci_dev->state_saved = false;
1248 	if (pm && pm->runtime_suspend) {
1249 		error = pm->runtime_suspend(dev);
1250 		/*
1251 		 * -EBUSY and -EAGAIN is used to request the runtime PM core
1252 		 * to schedule a new suspend, so log the event only with debug
1253 		 * log level.
1254 		 */
1255 		if (error == -EBUSY || error == -EAGAIN) {
1256 			pci_dbg(pci_dev, "can't suspend now (%ps returned %d)\n",
1257 				pm->runtime_suspend, error);
1258 			return error;
1259 		} else if (error) {
1260 			pci_err(pci_dev, "can't suspend (%ps returned %d)\n",
1261 				pm->runtime_suspend, error);
1262 			return error;
1263 		}
1264 	}
1265 
1266 	pci_fixup_device(pci_fixup_suspend, pci_dev);
1267 
1268 	if (pm && pm->runtime_suspend
1269 	    && !pci_dev->state_saved && pci_dev->current_state != PCI_D0
1270 	    && pci_dev->current_state != PCI_UNKNOWN) {
1271 		pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
1272 			      "PCI PM: State of device not saved by %pS\n",
1273 			      pm->runtime_suspend);
1274 		return 0;
1275 	}
1276 
1277 	if (!pci_dev->state_saved) {
1278 		pci_save_state(pci_dev);
1279 		pci_finish_runtime_suspend(pci_dev);
1280 	}
1281 
1282 	return 0;
1283 }
1284 
pci_pm_runtime_resume(struct device *dev)1285 static int pci_pm_runtime_resume(struct device *dev)
1286 {
1287 	struct pci_dev *pci_dev = to_pci_dev(dev);
1288 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1289 	pci_power_t prev_state = pci_dev->current_state;
1290 	int error = 0;
1291 
1292 	/*
1293 	 * Restoring config space is necessary even if the device is not bound
1294 	 * to a driver because although we left it in D0, it may have gone to
1295 	 * D3cold when the bridge above it runtime suspended.
1296 	 */
1297 	pci_restore_standard_config(pci_dev);
1298 
1299 	if (!pci_dev->driver)
1300 		return 0;
1301 
1302 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
1303 	pci_pm_default_resume(pci_dev);
1304 
1305 	if (prev_state == PCI_D3cold)
1306 		pci_bridge_wait_for_secondary_bus(pci_dev, "resume", PCI_RESET_WAIT);
1307 
1308 	if (pm && pm->runtime_resume)
1309 		error = pm->runtime_resume(dev);
1310 
1311 	pci_dev->runtime_d3cold = false;
1312 
1313 	return error;
1314 }
1315 
pci_pm_runtime_idle(struct device *dev)1316 static int pci_pm_runtime_idle(struct device *dev)
1317 {
1318 	struct pci_dev *pci_dev = to_pci_dev(dev);
1319 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1320 
1321 	/*
1322 	 * If pci_dev->driver is not set (unbound), the device should
1323 	 * always remain in D0 regardless of the runtime PM status
1324 	 */
1325 	if (!pci_dev->driver)
1326 		return 0;
1327 
1328 	if (!pm)
1329 		return -ENOSYS;
1330 
1331 	if (pm->runtime_idle)
1332 		return pm->runtime_idle(dev);
1333 
1334 	return 0;
1335 }
1336 
1337 static const struct dev_pm_ops pci_dev_pm_ops = {
1338 	.prepare = pci_pm_prepare,
1339 	.complete = pci_pm_complete,
1340 	.suspend = pci_pm_suspend,
1341 	.suspend_late = pci_pm_suspend_late,
1342 	.resume = pci_pm_resume,
1343 	.resume_early = pci_pm_resume_early,
1344 	.freeze = pci_pm_freeze,
1345 	.thaw = pci_pm_thaw,
1346 	.poweroff = pci_pm_poweroff,
1347 	.poweroff_late = pci_pm_poweroff_late,
1348 	.restore = pci_pm_restore,
1349 	.suspend_noirq = pci_pm_suspend_noirq,
1350 	.resume_noirq = pci_pm_resume_noirq,
1351 	.freeze_noirq = pci_pm_freeze_noirq,
1352 	.thaw_noirq = pci_pm_thaw_noirq,
1353 	.poweroff_noirq = pci_pm_poweroff_noirq,
1354 	.restore_noirq = pci_pm_restore_noirq,
1355 	.runtime_suspend = pci_pm_runtime_suspend,
1356 	.runtime_resume = pci_pm_runtime_resume,
1357 	.runtime_idle = pci_pm_runtime_idle,
1358 };
1359 
1360 #define PCI_PM_OPS_PTR	(&pci_dev_pm_ops)
1361 
1362 #else /* !CONFIG_PM */
1363 
1364 #define pci_pm_runtime_suspend	NULL
1365 #define pci_pm_runtime_resume	NULL
1366 #define pci_pm_runtime_idle	NULL
1367 
1368 #define PCI_PM_OPS_PTR	NULL
1369 
1370 #endif /* !CONFIG_PM */
1371 
1372 /**
1373  * __pci_register_driver - register a new pci driver
1374  * @drv: the driver structure to register
1375  * @owner: owner module of drv
1376  * @mod_name: module name string
1377  *
1378  * Adds the driver structure to the list of registered drivers.
1379  * Returns a negative value on error, otherwise 0.
1380  * If no error occurred, the driver remains registered even if
1381  * no device was claimed during registration.
1382  */
__pci_register_driver(struct pci_driver *drv, struct module *owner, const char *mod_name)1383 int __pci_register_driver(struct pci_driver *drv, struct module *owner,
1384 			  const char *mod_name)
1385 {
1386 	/* initialize common driver fields */
1387 	drv->driver.name = drv->name;
1388 	drv->driver.bus = &pci_bus_type;
1389 	drv->driver.owner = owner;
1390 	drv->driver.mod_name = mod_name;
1391 	drv->driver.groups = drv->groups;
1392 
1393 	spin_lock_init(&drv->dynids.lock);
1394 	INIT_LIST_HEAD(&drv->dynids.list);
1395 
1396 	/* register with core */
1397 	return driver_register(&drv->driver);
1398 }
1399 EXPORT_SYMBOL(__pci_register_driver);
1400 
1401 /**
1402  * pci_unregister_driver - unregister a pci driver
1403  * @drv: the driver structure to unregister
1404  *
1405  * Deletes the driver structure from the list of registered PCI drivers,
1406  * gives it a chance to clean up by calling its remove() function for
1407  * each device it was responsible for, and marks those devices as
1408  * driverless.
1409  */
1410 
pci_unregister_driver(struct pci_driver *drv)1411 void pci_unregister_driver(struct pci_driver *drv)
1412 {
1413 	driver_unregister(&drv->driver);
1414 	pci_free_dynids(drv);
1415 }
1416 EXPORT_SYMBOL(pci_unregister_driver);
1417 
1418 static struct pci_driver pci_compat_driver = {
1419 	.name = "compat"
1420 };
1421 
1422 /**
1423  * pci_dev_driver - get the pci_driver of a device
1424  * @dev: the device to query
1425  *
1426  * Returns the appropriate pci_driver structure or %NULL if there is no
1427  * registered driver for the device.
1428  */
pci_dev_driver(const struct pci_dev *dev)1429 struct pci_driver *pci_dev_driver(const struct pci_dev *dev)
1430 {
1431 	if (dev->driver)
1432 		return dev->driver;
1433 	else {
1434 		int i;
1435 		for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1436 			if (dev->resource[i].flags & IORESOURCE_BUSY)
1437 				return &pci_compat_driver;
1438 	}
1439 	return NULL;
1440 }
1441 EXPORT_SYMBOL(pci_dev_driver);
1442 
1443 /**
1444  * pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure
1445  * @dev: the PCI device structure to match against
1446  * @drv: the device driver to search for matching PCI device id structures
1447  *
1448  * Used by a driver to check whether a PCI device present in the
1449  * system is in its list of supported devices. Returns the matching
1450  * pci_device_id structure or %NULL if there is no match.
1451  */
pci_bus_match(struct device *dev, struct device_driver *drv)1452 static int pci_bus_match(struct device *dev, struct device_driver *drv)
1453 {
1454 	struct pci_dev *pci_dev = to_pci_dev(dev);
1455 	struct pci_driver *pci_drv;
1456 	const struct pci_device_id *found_id;
1457 
1458 	if (!pci_dev->match_driver)
1459 		return 0;
1460 
1461 	pci_drv = to_pci_driver(drv);
1462 	found_id = pci_match_device(pci_drv, pci_dev);
1463 	if (found_id)
1464 		return 1;
1465 
1466 	return 0;
1467 }
1468 
1469 /**
1470  * pci_dev_get - increments the reference count of the pci device structure
1471  * @dev: the device being referenced
1472  *
1473  * Each live reference to a device should be refcounted.
1474  *
1475  * Drivers for PCI devices should normally record such references in
1476  * their probe() methods, when they bind to a device, and release
1477  * them by calling pci_dev_put(), in their disconnect() methods.
1478  *
1479  * A pointer to the device with the incremented reference counter is returned.
1480  */
pci_dev_get(struct pci_dev *dev)1481 struct pci_dev *pci_dev_get(struct pci_dev *dev)
1482 {
1483 	if (dev)
1484 		get_device(&dev->dev);
1485 	return dev;
1486 }
1487 EXPORT_SYMBOL(pci_dev_get);
1488 
1489 /**
1490  * pci_dev_put - release a use of the pci device structure
1491  * @dev: device that's been disconnected
1492  *
1493  * Must be called when a user of a device is finished with it.  When the last
1494  * user of the device calls this function, the memory of the device is freed.
1495  */
pci_dev_put(struct pci_dev *dev)1496 void pci_dev_put(struct pci_dev *dev)
1497 {
1498 	if (dev)
1499 		put_device(&dev->dev);
1500 }
1501 EXPORT_SYMBOL(pci_dev_put);
1502 
pci_uevent(struct device *dev, struct kobj_uevent_env *env)1503 static int pci_uevent(struct device *dev, struct kobj_uevent_env *env)
1504 {
1505 	struct pci_dev *pdev;
1506 
1507 	if (!dev)
1508 		return -ENODEV;
1509 
1510 	pdev = to_pci_dev(dev);
1511 
1512 	if (add_uevent_var(env, "PCI_CLASS=%04X", pdev->class))
1513 		return -ENOMEM;
1514 
1515 	if (add_uevent_var(env, "PCI_ID=%04X:%04X", pdev->vendor, pdev->device))
1516 		return -ENOMEM;
1517 
1518 	if (add_uevent_var(env, "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,
1519 			   pdev->subsystem_device))
1520 		return -ENOMEM;
1521 
1522 	if (add_uevent_var(env, "PCI_SLOT_NAME=%s", pci_name(pdev)))
1523 		return -ENOMEM;
1524 
1525 	if (add_uevent_var(env, "MODALIAS=pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X",
1526 			   pdev->vendor, pdev->device,
1527 			   pdev->subsystem_vendor, pdev->subsystem_device,
1528 			   (u8)(pdev->class >> 16), (u8)(pdev->class >> 8),
1529 			   (u8)(pdev->class)))
1530 		return -ENOMEM;
1531 
1532 	return 0;
1533 }
1534 
1535 #if defined(CONFIG_PCIEPORTBUS) || defined(CONFIG_EEH)
1536 /**
1537  * pci_uevent_ers - emit a uevent during recovery path of PCI device
1538  * @pdev: PCI device undergoing error recovery
1539  * @err_type: type of error event
1540  */
pci_uevent_ers(struct pci_dev *pdev, enum pci_ers_result err_type)1541 void pci_uevent_ers(struct pci_dev *pdev, enum pci_ers_result err_type)
1542 {
1543 	int idx = 0;
1544 	char *envp[3];
1545 
1546 	switch (err_type) {
1547 	case PCI_ERS_RESULT_NONE:
1548 	case PCI_ERS_RESULT_CAN_RECOVER:
1549 		envp[idx++] = "ERROR_EVENT=BEGIN_RECOVERY";
1550 		envp[idx++] = "DEVICE_ONLINE=0";
1551 		break;
1552 	case PCI_ERS_RESULT_RECOVERED:
1553 		envp[idx++] = "ERROR_EVENT=SUCCESSFUL_RECOVERY";
1554 		envp[idx++] = "DEVICE_ONLINE=1";
1555 		break;
1556 	case PCI_ERS_RESULT_DISCONNECT:
1557 		envp[idx++] = "ERROR_EVENT=FAILED_RECOVERY";
1558 		envp[idx++] = "DEVICE_ONLINE=0";
1559 		break;
1560 	default:
1561 		break;
1562 	}
1563 
1564 	if (idx > 0) {
1565 		envp[idx++] = NULL;
1566 		kobject_uevent_env(&pdev->dev.kobj, KOBJ_CHANGE, envp);
1567 	}
1568 }
1569 #endif
1570 
pci_bus_num_vf(struct device *dev)1571 static int pci_bus_num_vf(struct device *dev)
1572 {
1573 	return pci_num_vf(to_pci_dev(dev));
1574 }
1575 
1576 /**
1577  * pci_dma_configure - Setup DMA configuration
1578  * @dev: ptr to dev structure
1579  *
1580  * Function to update PCI devices's DMA configuration using the same
1581  * info from the OF node or ACPI node of host bridge's parent (if any).
1582  */
pci_dma_configure(struct device *dev)1583 static int pci_dma_configure(struct device *dev)
1584 {
1585 	struct device *bridge;
1586 	int ret = 0;
1587 
1588 	bridge = pci_get_host_bridge_device(to_pci_dev(dev));
1589 
1590 	if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
1591 	    bridge->parent->of_node) {
1592 		ret = of_dma_configure(dev, bridge->parent->of_node, true);
1593 	} else if (has_acpi_companion(bridge)) {
1594 		struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
1595 
1596 		ret = acpi_dma_configure(dev, acpi_get_dma_attr(adev));
1597 	}
1598 
1599 	pci_put_host_bridge_device(bridge);
1600 	return ret;
1601 }
1602 
1603 struct bus_type pci_bus_type = {
1604 	.name		= "pci",
1605 	.match		= pci_bus_match,
1606 	.uevent		= pci_uevent,
1607 	.probe		= pci_device_probe,
1608 	.remove		= pci_device_remove,
1609 	.shutdown	= pci_device_shutdown,
1610 	.dev_groups	= pci_dev_groups,
1611 	.bus_groups	= pci_bus_groups,
1612 	.drv_groups	= pci_drv_groups,
1613 	.pm		= PCI_PM_OPS_PTR,
1614 	.num_vf		= pci_bus_num_vf,
1615 	.dma_configure	= pci_dma_configure,
1616 };
1617 EXPORT_SYMBOL(pci_bus_type);
1618 
1619 #ifdef CONFIG_PCIEPORTBUS
pcie_port_bus_match(struct device *dev, struct device_driver *drv)1620 static int pcie_port_bus_match(struct device *dev, struct device_driver *drv)
1621 {
1622 	struct pcie_device *pciedev;
1623 	struct pcie_port_service_driver *driver;
1624 
1625 	if (drv->bus != &pcie_port_bus_type || dev->bus != &pcie_port_bus_type)
1626 		return 0;
1627 
1628 	pciedev = to_pcie_device(dev);
1629 	driver = to_service_driver(drv);
1630 
1631 	if (driver->service != pciedev->service)
1632 		return 0;
1633 
1634 	if (driver->port_type != PCIE_ANY_PORT &&
1635 	    driver->port_type != pci_pcie_type(pciedev->port))
1636 		return 0;
1637 
1638 	return 1;
1639 }
1640 
1641 struct bus_type pcie_port_bus_type = {
1642 	.name		= "pci_express",
1643 	.match		= pcie_port_bus_match,
1644 };
1645 EXPORT_SYMBOL_GPL(pcie_port_bus_type);
1646 #endif
1647 
pci_driver_init(void)1648 static int __init pci_driver_init(void)
1649 {
1650 	int ret;
1651 
1652 	ret = bus_register(&pci_bus_type);
1653 	if (ret)
1654 		return ret;
1655 
1656 #ifdef CONFIG_PCIEPORTBUS
1657 	ret = bus_register(&pcie_port_bus_type);
1658 	if (ret)
1659 		return ret;
1660 #endif
1661 	dma_debug_add_bus(&pci_bus_type);
1662 	return 0;
1663 }
1664 postcore_initcall(pci_driver_init);
1665