xref: /linux/drivers/pci/pci.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
1 /*
2  *	PCI Bus Services, see include/linux/pci.h for further explanation.
3  *
4  *	Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
5  *	David Mosberger-Tang
6  *
7  *	Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/delay.h>
12 #include <linux/init.h>
13 #include <linux/pci.h>
14 #include <linux/pm.h>
15 #include <linux/slab.h>
16 #include <linux/module.h>
17 #include <linux/spinlock.h>
18 #include <linux/string.h>
19 #include <linux/log2.h>
20 #include <linux/pci-aspm.h>
21 #include <linux/pm_wakeup.h>
22 #include <linux/interrupt.h>
23 #include <linux/device.h>
24 #include <linux/pm_runtime.h>
25 #include <asm/setup.h>
26 #include "pci.h"
27 
28 const char *pci_power_names[] = {
29 	"error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
30 };
31 EXPORT_SYMBOL_GPL(pci_power_names);
32 
33 int isa_dma_bridge_buggy;
34 EXPORT_SYMBOL(isa_dma_bridge_buggy);
35 
36 int pci_pci_problems;
37 EXPORT_SYMBOL(pci_pci_problems);
38 
39 unsigned int pci_pm_d3_delay;
40 
41 static void pci_dev_d3_sleep(struct pci_dev *dev)
42 {
43 	unsigned int delay = dev->d3_delay;
44 
45 	if (delay < pci_pm_d3_delay)
46 		delay = pci_pm_d3_delay;
47 
48 	msleep(delay);
49 }
50 
51 #ifdef CONFIG_PCI_DOMAINS
52 int pci_domains_supported = 1;
53 #endif
54 
55 #define DEFAULT_CARDBUS_IO_SIZE		(256)
56 #define DEFAULT_CARDBUS_MEM_SIZE	(64*1024*1024)
57 /* pci=cbmemsize=nnM,cbiosize=nn can override this */
58 unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
59 unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
60 
61 #define DEFAULT_HOTPLUG_IO_SIZE		(256)
62 #define DEFAULT_HOTPLUG_MEM_SIZE	(2*1024*1024)
63 /* pci=hpmemsize=nnM,hpiosize=nn can override this */
64 unsigned long pci_hotplug_io_size  = DEFAULT_HOTPLUG_IO_SIZE;
65 unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
66 
67 /*
68  * The default CLS is used if arch didn't set CLS explicitly and not
69  * all pci devices agree on the same value.  Arch can override either
70  * the dfl or actual value as it sees fit.  Don't forget this is
71  * measured in 32-bit words, not bytes.
72  */
73 u8 pci_dfl_cache_line_size __devinitdata = L1_CACHE_BYTES >> 2;
74 u8 pci_cache_line_size;
75 
76 /**
77  * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
78  * @bus: pointer to PCI bus structure to search
79  *
80  * Given a PCI bus, returns the highest PCI bus number present in the set
81  * including the given PCI bus and its list of child PCI buses.
82  */
83 unsigned char pci_bus_max_busnr(struct pci_bus* bus)
84 {
85 	struct list_head *tmp;
86 	unsigned char max, n;
87 
88 	max = bus->subordinate;
89 	list_for_each(tmp, &bus->children) {
90 		n = pci_bus_max_busnr(pci_bus_b(tmp));
91 		if(n > max)
92 			max = n;
93 	}
94 	return max;
95 }
96 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
97 
98 #ifdef CONFIG_HAS_IOMEM
99 void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
100 {
101 	/*
102 	 * Make sure the BAR is actually a memory resource, not an IO resource
103 	 */
104 	if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
105 		WARN_ON(1);
106 		return NULL;
107 	}
108 	return ioremap_nocache(pci_resource_start(pdev, bar),
109 				     pci_resource_len(pdev, bar));
110 }
111 EXPORT_SYMBOL_GPL(pci_ioremap_bar);
112 #endif
113 
114 #if 0
115 /**
116  * pci_max_busnr - returns maximum PCI bus number
117  *
118  * Returns the highest PCI bus number present in the system global list of
119  * PCI buses.
120  */
121 unsigned char __devinit
122 pci_max_busnr(void)
123 {
124 	struct pci_bus *bus = NULL;
125 	unsigned char max, n;
126 
127 	max = 0;
128 	while ((bus = pci_find_next_bus(bus)) != NULL) {
129 		n = pci_bus_max_busnr(bus);
130 		if(n > max)
131 			max = n;
132 	}
133 	return max;
134 }
135 
136 #endif  /*  0  */
137 
138 #define PCI_FIND_CAP_TTL	48
139 
140 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
141 				   u8 pos, int cap, int *ttl)
142 {
143 	u8 id;
144 
145 	while ((*ttl)--) {
146 		pci_bus_read_config_byte(bus, devfn, pos, &pos);
147 		if (pos < 0x40)
148 			break;
149 		pos &= ~3;
150 		pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
151 					 &id);
152 		if (id == 0xff)
153 			break;
154 		if (id == cap)
155 			return pos;
156 		pos += PCI_CAP_LIST_NEXT;
157 	}
158 	return 0;
159 }
160 
161 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
162 			       u8 pos, int cap)
163 {
164 	int ttl = PCI_FIND_CAP_TTL;
165 
166 	return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
167 }
168 
169 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
170 {
171 	return __pci_find_next_cap(dev->bus, dev->devfn,
172 				   pos + PCI_CAP_LIST_NEXT, cap);
173 }
174 EXPORT_SYMBOL_GPL(pci_find_next_capability);
175 
176 static int __pci_bus_find_cap_start(struct pci_bus *bus,
177 				    unsigned int devfn, u8 hdr_type)
178 {
179 	u16 status;
180 
181 	pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
182 	if (!(status & PCI_STATUS_CAP_LIST))
183 		return 0;
184 
185 	switch (hdr_type) {
186 	case PCI_HEADER_TYPE_NORMAL:
187 	case PCI_HEADER_TYPE_BRIDGE:
188 		return PCI_CAPABILITY_LIST;
189 	case PCI_HEADER_TYPE_CARDBUS:
190 		return PCI_CB_CAPABILITY_LIST;
191 	default:
192 		return 0;
193 	}
194 
195 	return 0;
196 }
197 
198 /**
199  * pci_find_capability - query for devices' capabilities
200  * @dev: PCI device to query
201  * @cap: capability code
202  *
203  * Tell if a device supports a given PCI capability.
204  * Returns the address of the requested capability structure within the
205  * device's PCI configuration space or 0 in case the device does not
206  * support it.  Possible values for @cap:
207  *
208  *  %PCI_CAP_ID_PM           Power Management
209  *  %PCI_CAP_ID_AGP          Accelerated Graphics Port
210  *  %PCI_CAP_ID_VPD          Vital Product Data
211  *  %PCI_CAP_ID_SLOTID       Slot Identification
212  *  %PCI_CAP_ID_MSI          Message Signalled Interrupts
213  *  %PCI_CAP_ID_CHSWP        CompactPCI HotSwap
214  *  %PCI_CAP_ID_PCIX         PCI-X
215  *  %PCI_CAP_ID_EXP          PCI Express
216  */
217 int pci_find_capability(struct pci_dev *dev, int cap)
218 {
219 	int pos;
220 
221 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
222 	if (pos)
223 		pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
224 
225 	return pos;
226 }
227 
228 /**
229  * pci_bus_find_capability - query for devices' capabilities
230  * @bus:   the PCI bus to query
231  * @devfn: PCI device to query
232  * @cap:   capability code
233  *
234  * Like pci_find_capability() but works for pci devices that do not have a
235  * pci_dev structure set up yet.
236  *
237  * Returns the address of the requested capability structure within the
238  * device's PCI configuration space or 0 in case the device does not
239  * support it.
240  */
241 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
242 {
243 	int pos;
244 	u8 hdr_type;
245 
246 	pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
247 
248 	pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
249 	if (pos)
250 		pos = __pci_find_next_cap(bus, devfn, pos, cap);
251 
252 	return pos;
253 }
254 
255 /**
256  * pci_find_ext_capability - Find an extended capability
257  * @dev: PCI device to query
258  * @cap: capability code
259  *
260  * Returns the address of the requested extended capability structure
261  * within the device's PCI configuration space or 0 if the device does
262  * not support it.  Possible values for @cap:
263  *
264  *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
265  *  %PCI_EXT_CAP_ID_VC		Virtual Channel
266  *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
267  *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
268  */
269 int pci_find_ext_capability(struct pci_dev *dev, int cap)
270 {
271 	u32 header;
272 	int ttl;
273 	int pos = PCI_CFG_SPACE_SIZE;
274 
275 	/* minimum 8 bytes per capability */
276 	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
277 
278 	if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
279 		return 0;
280 
281 	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
282 		return 0;
283 
284 	/*
285 	 * If we have no capabilities, this is indicated by cap ID,
286 	 * cap version and next pointer all being 0.
287 	 */
288 	if (header == 0)
289 		return 0;
290 
291 	while (ttl-- > 0) {
292 		if (PCI_EXT_CAP_ID(header) == cap)
293 			return pos;
294 
295 		pos = PCI_EXT_CAP_NEXT(header);
296 		if (pos < PCI_CFG_SPACE_SIZE)
297 			break;
298 
299 		if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
300 			break;
301 	}
302 
303 	return 0;
304 }
305 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
306 
307 /**
308  * pci_bus_find_ext_capability - find an extended capability
309  * @bus:   the PCI bus to query
310  * @devfn: PCI device to query
311  * @cap:   capability code
312  *
313  * Like pci_find_ext_capability() but works for pci devices that do not have a
314  * pci_dev structure set up yet.
315  *
316  * Returns the address of the requested capability structure within the
317  * device's PCI configuration space or 0 in case the device does not
318  * support it.
319  */
320 int pci_bus_find_ext_capability(struct pci_bus *bus, unsigned int devfn,
321 				int cap)
322 {
323 	u32 header;
324 	int ttl;
325 	int pos = PCI_CFG_SPACE_SIZE;
326 
327 	/* minimum 8 bytes per capability */
328 	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
329 
330 	if (!pci_bus_read_config_dword(bus, devfn, pos, &header))
331 		return 0;
332 	if (header == 0xffffffff || header == 0)
333 		return 0;
334 
335 	while (ttl-- > 0) {
336 		if (PCI_EXT_CAP_ID(header) == cap)
337 			return pos;
338 
339 		pos = PCI_EXT_CAP_NEXT(header);
340 		if (pos < PCI_CFG_SPACE_SIZE)
341 			break;
342 
343 		if (!pci_bus_read_config_dword(bus, devfn, pos, &header))
344 			break;
345 	}
346 
347 	return 0;
348 }
349 
350 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
351 {
352 	int rc, ttl = PCI_FIND_CAP_TTL;
353 	u8 cap, mask;
354 
355 	if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
356 		mask = HT_3BIT_CAP_MASK;
357 	else
358 		mask = HT_5BIT_CAP_MASK;
359 
360 	pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
361 				      PCI_CAP_ID_HT, &ttl);
362 	while (pos) {
363 		rc = pci_read_config_byte(dev, pos + 3, &cap);
364 		if (rc != PCIBIOS_SUCCESSFUL)
365 			return 0;
366 
367 		if ((cap & mask) == ht_cap)
368 			return pos;
369 
370 		pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
371 					      pos + PCI_CAP_LIST_NEXT,
372 					      PCI_CAP_ID_HT, &ttl);
373 	}
374 
375 	return 0;
376 }
377 /**
378  * pci_find_next_ht_capability - query a device's Hypertransport capabilities
379  * @dev: PCI device to query
380  * @pos: Position from which to continue searching
381  * @ht_cap: Hypertransport capability code
382  *
383  * To be used in conjunction with pci_find_ht_capability() to search for
384  * all capabilities matching @ht_cap. @pos should always be a value returned
385  * from pci_find_ht_capability().
386  *
387  * NB. To be 100% safe against broken PCI devices, the caller should take
388  * steps to avoid an infinite loop.
389  */
390 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
391 {
392 	return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
393 }
394 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
395 
396 /**
397  * pci_find_ht_capability - query a device's Hypertransport capabilities
398  * @dev: PCI device to query
399  * @ht_cap: Hypertransport capability code
400  *
401  * Tell if a device supports a given Hypertransport capability.
402  * Returns an address within the device's PCI configuration space
403  * or 0 in case the device does not support the request capability.
404  * The address points to the PCI capability, of type PCI_CAP_ID_HT,
405  * which has a Hypertransport capability matching @ht_cap.
406  */
407 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
408 {
409 	int pos;
410 
411 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
412 	if (pos)
413 		pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
414 
415 	return pos;
416 }
417 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
418 
419 /**
420  * pci_find_parent_resource - return resource region of parent bus of given region
421  * @dev: PCI device structure contains resources to be searched
422  * @res: child resource record for which parent is sought
423  *
424  *  For given resource region of given device, return the resource
425  *  region of parent bus the given region is contained in or where
426  *  it should be allocated from.
427  */
428 struct resource *
429 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
430 {
431 	const struct pci_bus *bus = dev->bus;
432 	int i;
433 	struct resource *best = NULL, *r;
434 
435 	pci_bus_for_each_resource(bus, r, i) {
436 		if (!r)
437 			continue;
438 		if (res->start && !(res->start >= r->start && res->end <= r->end))
439 			continue;	/* Not contained */
440 		if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
441 			continue;	/* Wrong type */
442 		if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
443 			return r;	/* Exact match */
444 		/* We can't insert a non-prefetch resource inside a prefetchable parent .. */
445 		if (r->flags & IORESOURCE_PREFETCH)
446 			continue;
447 		/* .. but we can put a prefetchable resource inside a non-prefetchable one */
448 		if (!best)
449 			best = r;
450 	}
451 	return best;
452 }
453 
454 /**
455  * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
456  * @dev: PCI device to have its BARs restored
457  *
458  * Restore the BAR values for a given device, so as to make it
459  * accessible by its driver.
460  */
461 static void
462 pci_restore_bars(struct pci_dev *dev)
463 {
464 	int i;
465 
466 	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
467 		pci_update_resource(dev, i);
468 }
469 
470 static struct pci_platform_pm_ops *pci_platform_pm;
471 
472 int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
473 {
474 	if (!ops->is_manageable || !ops->set_state || !ops->choose_state
475 	    || !ops->sleep_wake || !ops->can_wakeup)
476 		return -EINVAL;
477 	pci_platform_pm = ops;
478 	return 0;
479 }
480 
481 static inline bool platform_pci_power_manageable(struct pci_dev *dev)
482 {
483 	return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
484 }
485 
486 static inline int platform_pci_set_power_state(struct pci_dev *dev,
487                                                 pci_power_t t)
488 {
489 	return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
490 }
491 
492 static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
493 {
494 	return pci_platform_pm ?
495 			pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
496 }
497 
498 static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
499 {
500 	return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
501 }
502 
503 static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
504 {
505 	return pci_platform_pm ?
506 			pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
507 }
508 
509 static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable)
510 {
511 	return pci_platform_pm ?
512 			pci_platform_pm->run_wake(dev, enable) : -ENODEV;
513 }
514 
515 /**
516  * pci_raw_set_power_state - Use PCI PM registers to set the power state of
517  *                           given PCI device
518  * @dev: PCI device to handle.
519  * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
520  *
521  * RETURN VALUE:
522  * -EINVAL if the requested state is invalid.
523  * -EIO if device does not support PCI PM or its PM capabilities register has a
524  * wrong version, or device doesn't support the requested state.
525  * 0 if device already is in the requested state.
526  * 0 if device's power state has been successfully changed.
527  */
528 static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
529 {
530 	u16 pmcsr;
531 	bool need_restore = false;
532 
533 	/* Check if we're already there */
534 	if (dev->current_state == state)
535 		return 0;
536 
537 	if (!dev->pm_cap)
538 		return -EIO;
539 
540 	if (state < PCI_D0 || state > PCI_D3hot)
541 		return -EINVAL;
542 
543 	/* Validate current state:
544 	 * Can enter D0 from any state, but if we can only go deeper
545 	 * to sleep if we're already in a low power state
546 	 */
547 	if (state != PCI_D0 && dev->current_state <= PCI_D3cold
548 	    && dev->current_state > state) {
549 		dev_err(&dev->dev, "invalid power transition "
550 			"(from state %d to %d)\n", dev->current_state, state);
551 		return -EINVAL;
552 	}
553 
554 	/* check if this device supports the desired state */
555 	if ((state == PCI_D1 && !dev->d1_support)
556 	   || (state == PCI_D2 && !dev->d2_support))
557 		return -EIO;
558 
559 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
560 
561 	/* If we're (effectively) in D3, force entire word to 0.
562 	 * This doesn't affect PME_Status, disables PME_En, and
563 	 * sets PowerState to 0.
564 	 */
565 	switch (dev->current_state) {
566 	case PCI_D0:
567 	case PCI_D1:
568 	case PCI_D2:
569 		pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
570 		pmcsr |= state;
571 		break;
572 	case PCI_D3hot:
573 	case PCI_D3cold:
574 	case PCI_UNKNOWN: /* Boot-up */
575 		if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
576 		 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
577 			need_restore = true;
578 		/* Fall-through: force to D0 */
579 	default:
580 		pmcsr = 0;
581 		break;
582 	}
583 
584 	/* enter specified state */
585 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
586 
587 	/* Mandatory power management transition delays */
588 	/* see PCI PM 1.1 5.6.1 table 18 */
589 	if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
590 		pci_dev_d3_sleep(dev);
591 	else if (state == PCI_D2 || dev->current_state == PCI_D2)
592 		udelay(PCI_PM_D2_DELAY);
593 
594 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
595 	dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
596 	if (dev->current_state != state && printk_ratelimit())
597 		dev_info(&dev->dev, "Refused to change power state, "
598 			"currently in D%d\n", dev->current_state);
599 
600 	/* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
601 	 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
602 	 * from D3hot to D0 _may_ perform an internal reset, thereby
603 	 * going to "D0 Uninitialized" rather than "D0 Initialized".
604 	 * For example, at least some versions of the 3c905B and the
605 	 * 3c556B exhibit this behaviour.
606 	 *
607 	 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
608 	 * devices in a D3hot state at boot.  Consequently, we need to
609 	 * restore at least the BARs so that the device will be
610 	 * accessible to its driver.
611 	 */
612 	if (need_restore)
613 		pci_restore_bars(dev);
614 
615 	if (dev->bus->self)
616 		pcie_aspm_pm_state_change(dev->bus->self);
617 
618 	return 0;
619 }
620 
621 /**
622  * pci_update_current_state - Read PCI power state of given device from its
623  *                            PCI PM registers and cache it
624  * @dev: PCI device to handle.
625  * @state: State to cache in case the device doesn't have the PM capability
626  */
627 void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
628 {
629 	if (dev->pm_cap) {
630 		u16 pmcsr;
631 
632 		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
633 		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
634 	} else {
635 		dev->current_state = state;
636 	}
637 }
638 
639 /**
640  * pci_platform_power_transition - Use platform to change device power state
641  * @dev: PCI device to handle.
642  * @state: State to put the device into.
643  */
644 static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
645 {
646 	int error;
647 
648 	if (platform_pci_power_manageable(dev)) {
649 		error = platform_pci_set_power_state(dev, state);
650 		if (!error)
651 			pci_update_current_state(dev, state);
652 	} else {
653 		error = -ENODEV;
654 		/* Fall back to PCI_D0 if native PM is not supported */
655 		if (!dev->pm_cap)
656 			dev->current_state = PCI_D0;
657 	}
658 
659 	return error;
660 }
661 
662 /**
663  * __pci_start_power_transition - Start power transition of a PCI device
664  * @dev: PCI device to handle.
665  * @state: State to put the device into.
666  */
667 static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
668 {
669 	if (state == PCI_D0)
670 		pci_platform_power_transition(dev, PCI_D0);
671 }
672 
673 /**
674  * __pci_complete_power_transition - Complete power transition of a PCI device
675  * @dev: PCI device to handle.
676  * @state: State to put the device into.
677  *
678  * This function should not be called directly by device drivers.
679  */
680 int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
681 {
682 	return state >= PCI_D0 ?
683 			pci_platform_power_transition(dev, state) : -EINVAL;
684 }
685 EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
686 
687 /**
688  * pci_set_power_state - Set the power state of a PCI device
689  * @dev: PCI device to handle.
690  * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
691  *
692  * Transition a device to a new power state, using the platform firmware and/or
693  * the device's PCI PM registers.
694  *
695  * RETURN VALUE:
696  * -EINVAL if the requested state is invalid.
697  * -EIO if device does not support PCI PM or its PM capabilities register has a
698  * wrong version, or device doesn't support the requested state.
699  * 0 if device already is in the requested state.
700  * 0 if device's power state has been successfully changed.
701  */
702 int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
703 {
704 	int error;
705 
706 	/* bound the state we're entering */
707 	if (state > PCI_D3hot)
708 		state = PCI_D3hot;
709 	else if (state < PCI_D0)
710 		state = PCI_D0;
711 	else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
712 		/*
713 		 * If the device or the parent bridge do not support PCI PM,
714 		 * ignore the request if we're doing anything other than putting
715 		 * it into D0 (which would only happen on boot).
716 		 */
717 		return 0;
718 
719 	__pci_start_power_transition(dev, state);
720 
721 	/* This device is quirked not to be put into D3, so
722 	   don't put it in D3 */
723 	if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
724 		return 0;
725 
726 	error = pci_raw_set_power_state(dev, state);
727 
728 	if (!__pci_complete_power_transition(dev, state))
729 		error = 0;
730 
731 	return error;
732 }
733 
734 /**
735  * pci_choose_state - Choose the power state of a PCI device
736  * @dev: PCI device to be suspended
737  * @state: target sleep state for the whole system. This is the value
738  *	that is passed to suspend() function.
739  *
740  * Returns PCI power state suitable for given device and given system
741  * message.
742  */
743 
744 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
745 {
746 	pci_power_t ret;
747 
748 	if (!pci_find_capability(dev, PCI_CAP_ID_PM))
749 		return PCI_D0;
750 
751 	ret = platform_pci_choose_state(dev);
752 	if (ret != PCI_POWER_ERROR)
753 		return ret;
754 
755 	switch (state.event) {
756 	case PM_EVENT_ON:
757 		return PCI_D0;
758 	case PM_EVENT_FREEZE:
759 	case PM_EVENT_PRETHAW:
760 		/* REVISIT both freeze and pre-thaw "should" use D0 */
761 	case PM_EVENT_SUSPEND:
762 	case PM_EVENT_HIBERNATE:
763 		return PCI_D3hot;
764 	default:
765 		dev_info(&dev->dev, "unrecognized suspend event %d\n",
766 			 state.event);
767 		BUG();
768 	}
769 	return PCI_D0;
770 }
771 
772 EXPORT_SYMBOL(pci_choose_state);
773 
774 #define PCI_EXP_SAVE_REGS	7
775 
776 #define pcie_cap_has_devctl(type, flags)	1
777 #define pcie_cap_has_lnkctl(type, flags)		\
778 		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
779 		 (type == PCI_EXP_TYPE_ROOT_PORT ||	\
780 		  type == PCI_EXP_TYPE_ENDPOINT ||	\
781 		  type == PCI_EXP_TYPE_LEG_END))
782 #define pcie_cap_has_sltctl(type, flags)		\
783 		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
784 		 ((type == PCI_EXP_TYPE_ROOT_PORT) ||	\
785 		  (type == PCI_EXP_TYPE_DOWNSTREAM &&	\
786 		   (flags & PCI_EXP_FLAGS_SLOT))))
787 #define pcie_cap_has_rtctl(type, flags)			\
788 		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
789 		 (type == PCI_EXP_TYPE_ROOT_PORT ||	\
790 		  type == PCI_EXP_TYPE_RC_EC))
791 #define pcie_cap_has_devctl2(type, flags)		\
792 		((flags & PCI_EXP_FLAGS_VERS) > 1)
793 #define pcie_cap_has_lnkctl2(type, flags)		\
794 		((flags & PCI_EXP_FLAGS_VERS) > 1)
795 #define pcie_cap_has_sltctl2(type, flags)		\
796 		((flags & PCI_EXP_FLAGS_VERS) > 1)
797 
798 static int pci_save_pcie_state(struct pci_dev *dev)
799 {
800 	int pos, i = 0;
801 	struct pci_cap_saved_state *save_state;
802 	u16 *cap;
803 	u16 flags;
804 
805 	pos = pci_pcie_cap(dev);
806 	if (!pos)
807 		return 0;
808 
809 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
810 	if (!save_state) {
811 		dev_err(&dev->dev, "buffer not found in %s\n", __func__);
812 		return -ENOMEM;
813 	}
814 	cap = (u16 *)&save_state->data[0];
815 
816 	pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
817 
818 	if (pcie_cap_has_devctl(dev->pcie_type, flags))
819 		pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
820 	if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
821 		pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
822 	if (pcie_cap_has_sltctl(dev->pcie_type, flags))
823 		pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
824 	if (pcie_cap_has_rtctl(dev->pcie_type, flags))
825 		pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
826 	if (pcie_cap_has_devctl2(dev->pcie_type, flags))
827 		pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &cap[i++]);
828 	if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
829 		pci_read_config_word(dev, pos + PCI_EXP_LNKCTL2, &cap[i++]);
830 	if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
831 		pci_read_config_word(dev, pos + PCI_EXP_SLTCTL2, &cap[i++]);
832 
833 	return 0;
834 }
835 
836 static void pci_restore_pcie_state(struct pci_dev *dev)
837 {
838 	int i = 0, pos;
839 	struct pci_cap_saved_state *save_state;
840 	u16 *cap;
841 	u16 flags;
842 
843 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
844 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
845 	if (!save_state || pos <= 0)
846 		return;
847 	cap = (u16 *)&save_state->data[0];
848 
849 	pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
850 
851 	if (pcie_cap_has_devctl(dev->pcie_type, flags))
852 		pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
853 	if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
854 		pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
855 	if (pcie_cap_has_sltctl(dev->pcie_type, flags))
856 		pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
857 	if (pcie_cap_has_rtctl(dev->pcie_type, flags))
858 		pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
859 	if (pcie_cap_has_devctl2(dev->pcie_type, flags))
860 		pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, cap[i++]);
861 	if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
862 		pci_write_config_word(dev, pos + PCI_EXP_LNKCTL2, cap[i++]);
863 	if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
864 		pci_write_config_word(dev, pos + PCI_EXP_SLTCTL2, cap[i++]);
865 }
866 
867 
868 static int pci_save_pcix_state(struct pci_dev *dev)
869 {
870 	int pos;
871 	struct pci_cap_saved_state *save_state;
872 
873 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
874 	if (pos <= 0)
875 		return 0;
876 
877 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
878 	if (!save_state) {
879 		dev_err(&dev->dev, "buffer not found in %s\n", __func__);
880 		return -ENOMEM;
881 	}
882 
883 	pci_read_config_word(dev, pos + PCI_X_CMD, (u16 *)save_state->data);
884 
885 	return 0;
886 }
887 
888 static void pci_restore_pcix_state(struct pci_dev *dev)
889 {
890 	int i = 0, pos;
891 	struct pci_cap_saved_state *save_state;
892 	u16 *cap;
893 
894 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
895 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
896 	if (!save_state || pos <= 0)
897 		return;
898 	cap = (u16 *)&save_state->data[0];
899 
900 	pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
901 }
902 
903 
904 /**
905  * pci_save_state - save the PCI configuration space of a device before suspending
906  * @dev: - PCI device that we're dealing with
907  */
908 int
909 pci_save_state(struct pci_dev *dev)
910 {
911 	int i;
912 	/* XXX: 100% dword access ok here? */
913 	for (i = 0; i < 16; i++)
914 		pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
915 	dev->state_saved = true;
916 	if ((i = pci_save_pcie_state(dev)) != 0)
917 		return i;
918 	if ((i = pci_save_pcix_state(dev)) != 0)
919 		return i;
920 	return 0;
921 }
922 
923 /**
924  * pci_restore_state - Restore the saved state of a PCI device
925  * @dev: - PCI device that we're dealing with
926  */
927 int
928 pci_restore_state(struct pci_dev *dev)
929 {
930 	int i;
931 	u32 val;
932 
933 	if (!dev->state_saved)
934 		return 0;
935 
936 	/* PCI Express register must be restored first */
937 	pci_restore_pcie_state(dev);
938 
939 	/*
940 	 * The Base Address register should be programmed before the command
941 	 * register(s)
942 	 */
943 	for (i = 15; i >= 0; i--) {
944 		pci_read_config_dword(dev, i * 4, &val);
945 		if (val != dev->saved_config_space[i]) {
946 			dev_printk(KERN_DEBUG, &dev->dev, "restoring config "
947 				"space at offset %#x (was %#x, writing %#x)\n",
948 				i, val, (int)dev->saved_config_space[i]);
949 			pci_write_config_dword(dev,i * 4,
950 				dev->saved_config_space[i]);
951 		}
952 	}
953 	pci_restore_pcix_state(dev);
954 	pci_restore_msi_state(dev);
955 	pci_restore_iov_state(dev);
956 
957 	dev->state_saved = false;
958 
959 	return 0;
960 }
961 
962 static int do_pci_enable_device(struct pci_dev *dev, int bars)
963 {
964 	int err;
965 
966 	err = pci_set_power_state(dev, PCI_D0);
967 	if (err < 0 && err != -EIO)
968 		return err;
969 	err = pcibios_enable_device(dev, bars);
970 	if (err < 0)
971 		return err;
972 	pci_fixup_device(pci_fixup_enable, dev);
973 
974 	return 0;
975 }
976 
977 /**
978  * pci_reenable_device - Resume abandoned device
979  * @dev: PCI device to be resumed
980  *
981  *  Note this function is a backend of pci_default_resume and is not supposed
982  *  to be called by normal code, write proper resume handler and use it instead.
983  */
984 int pci_reenable_device(struct pci_dev *dev)
985 {
986 	if (pci_is_enabled(dev))
987 		return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
988 	return 0;
989 }
990 
991 static int __pci_enable_device_flags(struct pci_dev *dev,
992 				     resource_size_t flags)
993 {
994 	int err;
995 	int i, bars = 0;
996 
997 	if (atomic_add_return(1, &dev->enable_cnt) > 1)
998 		return 0;		/* already enabled */
999 
1000 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1001 		if (dev->resource[i].flags & flags)
1002 			bars |= (1 << i);
1003 
1004 	err = do_pci_enable_device(dev, bars);
1005 	if (err < 0)
1006 		atomic_dec(&dev->enable_cnt);
1007 	return err;
1008 }
1009 
1010 /**
1011  * pci_enable_device_io - Initialize a device for use with IO space
1012  * @dev: PCI device to be initialized
1013  *
1014  *  Initialize device before it's used by a driver. Ask low-level code
1015  *  to enable I/O resources. Wake up the device if it was suspended.
1016  *  Beware, this function can fail.
1017  */
1018 int pci_enable_device_io(struct pci_dev *dev)
1019 {
1020 	return __pci_enable_device_flags(dev, IORESOURCE_IO);
1021 }
1022 
1023 /**
1024  * pci_enable_device_mem - Initialize a device for use with Memory space
1025  * @dev: PCI device to be initialized
1026  *
1027  *  Initialize device before it's used by a driver. Ask low-level code
1028  *  to enable Memory resources. Wake up the device if it was suspended.
1029  *  Beware, this function can fail.
1030  */
1031 int pci_enable_device_mem(struct pci_dev *dev)
1032 {
1033 	return __pci_enable_device_flags(dev, IORESOURCE_MEM);
1034 }
1035 
1036 /**
1037  * pci_enable_device - Initialize device before it's used by a driver.
1038  * @dev: PCI device to be initialized
1039  *
1040  *  Initialize device before it's used by a driver. Ask low-level code
1041  *  to enable I/O and memory. Wake up the device if it was suspended.
1042  *  Beware, this function can fail.
1043  *
1044  *  Note we don't actually enable the device many times if we call
1045  *  this function repeatedly (we just increment the count).
1046  */
1047 int pci_enable_device(struct pci_dev *dev)
1048 {
1049 	return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
1050 }
1051 
1052 /*
1053  * Managed PCI resources.  This manages device on/off, intx/msi/msix
1054  * on/off and BAR regions.  pci_dev itself records msi/msix status, so
1055  * there's no need to track it separately.  pci_devres is initialized
1056  * when a device is enabled using managed PCI device enable interface.
1057  */
1058 struct pci_devres {
1059 	unsigned int enabled:1;
1060 	unsigned int pinned:1;
1061 	unsigned int orig_intx:1;
1062 	unsigned int restore_intx:1;
1063 	u32 region_mask;
1064 };
1065 
1066 static void pcim_release(struct device *gendev, void *res)
1067 {
1068 	struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
1069 	struct pci_devres *this = res;
1070 	int i;
1071 
1072 	if (dev->msi_enabled)
1073 		pci_disable_msi(dev);
1074 	if (dev->msix_enabled)
1075 		pci_disable_msix(dev);
1076 
1077 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1078 		if (this->region_mask & (1 << i))
1079 			pci_release_region(dev, i);
1080 
1081 	if (this->restore_intx)
1082 		pci_intx(dev, this->orig_intx);
1083 
1084 	if (this->enabled && !this->pinned)
1085 		pci_disable_device(dev);
1086 }
1087 
1088 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
1089 {
1090 	struct pci_devres *dr, *new_dr;
1091 
1092 	dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1093 	if (dr)
1094 		return dr;
1095 
1096 	new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1097 	if (!new_dr)
1098 		return NULL;
1099 	return devres_get(&pdev->dev, new_dr, NULL, NULL);
1100 }
1101 
1102 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
1103 {
1104 	if (pci_is_managed(pdev))
1105 		return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1106 	return NULL;
1107 }
1108 
1109 /**
1110  * pcim_enable_device - Managed pci_enable_device()
1111  * @pdev: PCI device to be initialized
1112  *
1113  * Managed pci_enable_device().
1114  */
1115 int pcim_enable_device(struct pci_dev *pdev)
1116 {
1117 	struct pci_devres *dr;
1118 	int rc;
1119 
1120 	dr = get_pci_dr(pdev);
1121 	if (unlikely(!dr))
1122 		return -ENOMEM;
1123 	if (dr->enabled)
1124 		return 0;
1125 
1126 	rc = pci_enable_device(pdev);
1127 	if (!rc) {
1128 		pdev->is_managed = 1;
1129 		dr->enabled = 1;
1130 	}
1131 	return rc;
1132 }
1133 
1134 /**
1135  * pcim_pin_device - Pin managed PCI device
1136  * @pdev: PCI device to pin
1137  *
1138  * Pin managed PCI device @pdev.  Pinned device won't be disabled on
1139  * driver detach.  @pdev must have been enabled with
1140  * pcim_enable_device().
1141  */
1142 void pcim_pin_device(struct pci_dev *pdev)
1143 {
1144 	struct pci_devres *dr;
1145 
1146 	dr = find_pci_dr(pdev);
1147 	WARN_ON(!dr || !dr->enabled);
1148 	if (dr)
1149 		dr->pinned = 1;
1150 }
1151 
1152 /**
1153  * pcibios_disable_device - disable arch specific PCI resources for device dev
1154  * @dev: the PCI device to disable
1155  *
1156  * Disables architecture specific PCI resources for the device. This
1157  * is the default implementation. Architecture implementations can
1158  * override this.
1159  */
1160 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
1161 
1162 static void do_pci_disable_device(struct pci_dev *dev)
1163 {
1164 	u16 pci_command;
1165 
1166 	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1167 	if (pci_command & PCI_COMMAND_MASTER) {
1168 		pci_command &= ~PCI_COMMAND_MASTER;
1169 		pci_write_config_word(dev, PCI_COMMAND, pci_command);
1170 	}
1171 
1172 	pcibios_disable_device(dev);
1173 }
1174 
1175 /**
1176  * pci_disable_enabled_device - Disable device without updating enable_cnt
1177  * @dev: PCI device to disable
1178  *
1179  * NOTE: This function is a backend of PCI power management routines and is
1180  * not supposed to be called drivers.
1181  */
1182 void pci_disable_enabled_device(struct pci_dev *dev)
1183 {
1184 	if (pci_is_enabled(dev))
1185 		do_pci_disable_device(dev);
1186 }
1187 
1188 /**
1189  * pci_disable_device - Disable PCI device after use
1190  * @dev: PCI device to be disabled
1191  *
1192  * Signal to the system that the PCI device is not in use by the system
1193  * anymore.  This only involves disabling PCI bus-mastering, if active.
1194  *
1195  * Note we don't actually disable the device until all callers of
1196  * pci_enable_device() have called pci_disable_device().
1197  */
1198 void
1199 pci_disable_device(struct pci_dev *dev)
1200 {
1201 	struct pci_devres *dr;
1202 
1203 	dr = find_pci_dr(dev);
1204 	if (dr)
1205 		dr->enabled = 0;
1206 
1207 	if (atomic_sub_return(1, &dev->enable_cnt) != 0)
1208 		return;
1209 
1210 	do_pci_disable_device(dev);
1211 
1212 	dev->is_busmaster = 0;
1213 }
1214 
1215 /**
1216  * pcibios_set_pcie_reset_state - set reset state for device dev
1217  * @dev: the PCIe device reset
1218  * @state: Reset state to enter into
1219  *
1220  *
1221  * Sets the PCIe reset state for the device. This is the default
1222  * implementation. Architecture implementations can override this.
1223  */
1224 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
1225 							enum pcie_reset_state state)
1226 {
1227 	return -EINVAL;
1228 }
1229 
1230 /**
1231  * pci_set_pcie_reset_state - set reset state for device dev
1232  * @dev: the PCIe device reset
1233  * @state: Reset state to enter into
1234  *
1235  *
1236  * Sets the PCI reset state for the device.
1237  */
1238 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1239 {
1240 	return pcibios_set_pcie_reset_state(dev, state);
1241 }
1242 
1243 /**
1244  * pci_check_pme_status - Check if given device has generated PME.
1245  * @dev: Device to check.
1246  *
1247  * Check the PME status of the device and if set, clear it and clear PME enable
1248  * (if set).  Return 'true' if PME status and PME enable were both set or
1249  * 'false' otherwise.
1250  */
1251 bool pci_check_pme_status(struct pci_dev *dev)
1252 {
1253 	int pmcsr_pos;
1254 	u16 pmcsr;
1255 	bool ret = false;
1256 
1257 	if (!dev->pm_cap)
1258 		return false;
1259 
1260 	pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
1261 	pci_read_config_word(dev, pmcsr_pos, &pmcsr);
1262 	if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
1263 		return false;
1264 
1265 	/* Clear PME status. */
1266 	pmcsr |= PCI_PM_CTRL_PME_STATUS;
1267 	if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
1268 		/* Disable PME to avoid interrupt flood. */
1269 		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1270 		ret = true;
1271 	}
1272 
1273 	pci_write_config_word(dev, pmcsr_pos, pmcsr);
1274 
1275 	return ret;
1276 }
1277 
1278 /*
1279  * Time to wait before the system can be put into a sleep state after reporting
1280  * a wakeup event signaled by a PCI device.
1281  */
1282 #define PCI_WAKEUP_COOLDOWN	100
1283 
1284 /**
1285  * pci_wakeup_event - Report a wakeup event related to a given PCI device.
1286  * @dev: Device to report the wakeup event for.
1287  */
1288 void pci_wakeup_event(struct pci_dev *dev)
1289 {
1290 	if (device_may_wakeup(&dev->dev))
1291 		pm_wakeup_event(&dev->dev, PCI_WAKEUP_COOLDOWN);
1292 }
1293 
1294 /**
1295  * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
1296  * @dev: Device to handle.
1297  * @ign: Ignored.
1298  *
1299  * Check if @dev has generated PME and queue a resume request for it in that
1300  * case.
1301  */
1302 static int pci_pme_wakeup(struct pci_dev *dev, void *ign)
1303 {
1304 	if (pci_check_pme_status(dev)) {
1305 		pm_request_resume(&dev->dev);
1306 		pci_wakeup_event(dev);
1307 	}
1308 	return 0;
1309 }
1310 
1311 /**
1312  * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
1313  * @bus: Top bus of the subtree to walk.
1314  */
1315 void pci_pme_wakeup_bus(struct pci_bus *bus)
1316 {
1317 	if (bus)
1318 		pci_walk_bus(bus, pci_pme_wakeup, NULL);
1319 }
1320 
1321 /**
1322  * pci_pme_capable - check the capability of PCI device to generate PME#
1323  * @dev: PCI device to handle.
1324  * @state: PCI state from which device will issue PME#.
1325  */
1326 bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1327 {
1328 	if (!dev->pm_cap)
1329 		return false;
1330 
1331 	return !!(dev->pme_support & (1 << state));
1332 }
1333 
1334 /**
1335  * pci_pme_active - enable or disable PCI device's PME# function
1336  * @dev: PCI device to handle.
1337  * @enable: 'true' to enable PME# generation; 'false' to disable it.
1338  *
1339  * The caller must verify that the device is capable of generating PME# before
1340  * calling this function with @enable equal to 'true'.
1341  */
1342 void pci_pme_active(struct pci_dev *dev, bool enable)
1343 {
1344 	u16 pmcsr;
1345 
1346 	if (!dev->pm_cap)
1347 		return;
1348 
1349 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1350 	/* Clear PME_Status by writing 1 to it and enable PME# */
1351 	pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1352 	if (!enable)
1353 		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1354 
1355 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1356 
1357 	dev_printk(KERN_DEBUG, &dev->dev, "PME# %s\n",
1358 			enable ? "enabled" : "disabled");
1359 }
1360 
1361 /**
1362  * __pci_enable_wake - enable PCI device as wakeup event source
1363  * @dev: PCI device affected
1364  * @state: PCI state from which device will issue wakeup events
1365  * @runtime: True if the events are to be generated at run time
1366  * @enable: True to enable event generation; false to disable
1367  *
1368  * This enables the device as a wakeup event source, or disables it.
1369  * When such events involves platform-specific hooks, those hooks are
1370  * called automatically by this routine.
1371  *
1372  * Devices with legacy power management (no standard PCI PM capabilities)
1373  * always require such platform hooks.
1374  *
1375  * RETURN VALUE:
1376  * 0 is returned on success
1377  * -EINVAL is returned if device is not supposed to wake up the system
1378  * Error code depending on the platform is returned if both the platform and
1379  * the native mechanism fail to enable the generation of wake-up events
1380  */
1381 int __pci_enable_wake(struct pci_dev *dev, pci_power_t state,
1382 		      bool runtime, bool enable)
1383 {
1384 	int ret = 0;
1385 
1386 	if (enable && !runtime && !device_may_wakeup(&dev->dev))
1387 		return -EINVAL;
1388 
1389 	/* Don't do the same thing twice in a row for one device. */
1390 	if (!!enable == !!dev->wakeup_prepared)
1391 		return 0;
1392 
1393 	/*
1394 	 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1395 	 * Anderson we should be doing PME# wake enable followed by ACPI wake
1396 	 * enable.  To disable wake-up we call the platform first, for symmetry.
1397 	 */
1398 
1399 	if (enable) {
1400 		int error;
1401 
1402 		if (pci_pme_capable(dev, state))
1403 			pci_pme_active(dev, true);
1404 		else
1405 			ret = 1;
1406 		error = runtime ? platform_pci_run_wake(dev, true) :
1407 					platform_pci_sleep_wake(dev, true);
1408 		if (ret)
1409 			ret = error;
1410 		if (!ret)
1411 			dev->wakeup_prepared = true;
1412 	} else {
1413 		if (runtime)
1414 			platform_pci_run_wake(dev, false);
1415 		else
1416 			platform_pci_sleep_wake(dev, false);
1417 		pci_pme_active(dev, false);
1418 		dev->wakeup_prepared = false;
1419 	}
1420 
1421 	return ret;
1422 }
1423 EXPORT_SYMBOL(__pci_enable_wake);
1424 
1425 /**
1426  * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1427  * @dev: PCI device to prepare
1428  * @enable: True to enable wake-up event generation; false to disable
1429  *
1430  * Many drivers want the device to wake up the system from D3_hot or D3_cold
1431  * and this function allows them to set that up cleanly - pci_enable_wake()
1432  * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1433  * ordering constraints.
1434  *
1435  * This function only returns error code if the device is not capable of
1436  * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1437  * enable wake-up power for it.
1438  */
1439 int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1440 {
1441 	return pci_pme_capable(dev, PCI_D3cold) ?
1442 			pci_enable_wake(dev, PCI_D3cold, enable) :
1443 			pci_enable_wake(dev, PCI_D3hot, enable);
1444 }
1445 
1446 /**
1447  * pci_target_state - find an appropriate low power state for a given PCI dev
1448  * @dev: PCI device
1449  *
1450  * Use underlying platform code to find a supported low power state for @dev.
1451  * If the platform can't manage @dev, return the deepest state from which it
1452  * can generate wake events, based on any available PME info.
1453  */
1454 pci_power_t pci_target_state(struct pci_dev *dev)
1455 {
1456 	pci_power_t target_state = PCI_D3hot;
1457 
1458 	if (platform_pci_power_manageable(dev)) {
1459 		/*
1460 		 * Call the platform to choose the target state of the device
1461 		 * and enable wake-up from this state if supported.
1462 		 */
1463 		pci_power_t state = platform_pci_choose_state(dev);
1464 
1465 		switch (state) {
1466 		case PCI_POWER_ERROR:
1467 		case PCI_UNKNOWN:
1468 			break;
1469 		case PCI_D1:
1470 		case PCI_D2:
1471 			if (pci_no_d1d2(dev))
1472 				break;
1473 		default:
1474 			target_state = state;
1475 		}
1476 	} else if (!dev->pm_cap) {
1477 		target_state = PCI_D0;
1478 	} else if (device_may_wakeup(&dev->dev)) {
1479 		/*
1480 		 * Find the deepest state from which the device can generate
1481 		 * wake-up events, make it the target state and enable device
1482 		 * to generate PME#.
1483 		 */
1484 		if (dev->pme_support) {
1485 			while (target_state
1486 			      && !(dev->pme_support & (1 << target_state)))
1487 				target_state--;
1488 		}
1489 	}
1490 
1491 	return target_state;
1492 }
1493 
1494 /**
1495  * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1496  * @dev: Device to handle.
1497  *
1498  * Choose the power state appropriate for the device depending on whether
1499  * it can wake up the system and/or is power manageable by the platform
1500  * (PCI_D3hot is the default) and put the device into that state.
1501  */
1502 int pci_prepare_to_sleep(struct pci_dev *dev)
1503 {
1504 	pci_power_t target_state = pci_target_state(dev);
1505 	int error;
1506 
1507 	if (target_state == PCI_POWER_ERROR)
1508 		return -EIO;
1509 
1510 	pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
1511 
1512 	error = pci_set_power_state(dev, target_state);
1513 
1514 	if (error)
1515 		pci_enable_wake(dev, target_state, false);
1516 
1517 	return error;
1518 }
1519 
1520 /**
1521  * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1522  * @dev: Device to handle.
1523  *
1524  * Disable device's system wake-up capability and put it into D0.
1525  */
1526 int pci_back_from_sleep(struct pci_dev *dev)
1527 {
1528 	pci_enable_wake(dev, PCI_D0, false);
1529 	return pci_set_power_state(dev, PCI_D0);
1530 }
1531 
1532 /**
1533  * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend.
1534  * @dev: PCI device being suspended.
1535  *
1536  * Prepare @dev to generate wake-up events at run time and put it into a low
1537  * power state.
1538  */
1539 int pci_finish_runtime_suspend(struct pci_dev *dev)
1540 {
1541 	pci_power_t target_state = pci_target_state(dev);
1542 	int error;
1543 
1544 	if (target_state == PCI_POWER_ERROR)
1545 		return -EIO;
1546 
1547 	__pci_enable_wake(dev, target_state, true, pci_dev_run_wake(dev));
1548 
1549 	error = pci_set_power_state(dev, target_state);
1550 
1551 	if (error)
1552 		__pci_enable_wake(dev, target_state, true, false);
1553 
1554 	return error;
1555 }
1556 
1557 /**
1558  * pci_dev_run_wake - Check if device can generate run-time wake-up events.
1559  * @dev: Device to check.
1560  *
1561  * Return true if the device itself is cabable of generating wake-up events
1562  * (through the platform or using the native PCIe PME) or if the device supports
1563  * PME and one of its upstream bridges can generate wake-up events.
1564  */
1565 bool pci_dev_run_wake(struct pci_dev *dev)
1566 {
1567 	struct pci_bus *bus = dev->bus;
1568 
1569 	if (device_run_wake(&dev->dev))
1570 		return true;
1571 
1572 	if (!dev->pme_support)
1573 		return false;
1574 
1575 	while (bus->parent) {
1576 		struct pci_dev *bridge = bus->self;
1577 
1578 		if (device_run_wake(&bridge->dev))
1579 			return true;
1580 
1581 		bus = bus->parent;
1582 	}
1583 
1584 	/* We have reached the root bus. */
1585 	if (bus->bridge)
1586 		return device_run_wake(bus->bridge);
1587 
1588 	return false;
1589 }
1590 EXPORT_SYMBOL_GPL(pci_dev_run_wake);
1591 
1592 /**
1593  * pci_pm_init - Initialize PM functions of given PCI device
1594  * @dev: PCI device to handle.
1595  */
1596 void pci_pm_init(struct pci_dev *dev)
1597 {
1598 	int pm;
1599 	u16 pmc;
1600 
1601 	pm_runtime_forbid(&dev->dev);
1602 	device_enable_async_suspend(&dev->dev);
1603 	dev->wakeup_prepared = false;
1604 
1605 	dev->pm_cap = 0;
1606 
1607 	/* find PCI PM capability in list */
1608 	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
1609 	if (!pm)
1610 		return;
1611 	/* Check device's ability to generate PME# */
1612 	pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
1613 
1614 	if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
1615 		dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
1616 			pmc & PCI_PM_CAP_VER_MASK);
1617 		return;
1618 	}
1619 
1620 	dev->pm_cap = pm;
1621 	dev->d3_delay = PCI_PM_D3_WAIT;
1622 
1623 	dev->d1_support = false;
1624 	dev->d2_support = false;
1625 	if (!pci_no_d1d2(dev)) {
1626 		if (pmc & PCI_PM_CAP_D1)
1627 			dev->d1_support = true;
1628 		if (pmc & PCI_PM_CAP_D2)
1629 			dev->d2_support = true;
1630 
1631 		if (dev->d1_support || dev->d2_support)
1632 			dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
1633 				   dev->d1_support ? " D1" : "",
1634 				   dev->d2_support ? " D2" : "");
1635 	}
1636 
1637 	pmc &= PCI_PM_CAP_PME_MASK;
1638 	if (pmc) {
1639 		dev_printk(KERN_DEBUG, &dev->dev,
1640 			 "PME# supported from%s%s%s%s%s\n",
1641 			 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
1642 			 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
1643 			 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
1644 			 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
1645 			 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
1646 		dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
1647 		/*
1648 		 * Make device's PM flags reflect the wake-up capability, but
1649 		 * let the user space enable it to wake up the system as needed.
1650 		 */
1651 		device_set_wakeup_capable(&dev->dev, true);
1652 		/* Disable the PME# generation functionality */
1653 		pci_pme_active(dev, false);
1654 	} else {
1655 		dev->pme_support = 0;
1656 	}
1657 }
1658 
1659 /**
1660  * platform_pci_wakeup_init - init platform wakeup if present
1661  * @dev: PCI device
1662  *
1663  * Some devices don't have PCI PM caps but can still generate wakeup
1664  * events through platform methods (like ACPI events).  If @dev supports
1665  * platform wakeup events, set the device flag to indicate as much.  This
1666  * may be redundant if the device also supports PCI PM caps, but double
1667  * initialization should be safe in that case.
1668  */
1669 void platform_pci_wakeup_init(struct pci_dev *dev)
1670 {
1671 	if (!platform_pci_can_wakeup(dev))
1672 		return;
1673 
1674 	device_set_wakeup_capable(&dev->dev, true);
1675 	platform_pci_sleep_wake(dev, false);
1676 }
1677 
1678 /**
1679  * pci_add_save_buffer - allocate buffer for saving given capability registers
1680  * @dev: the PCI device
1681  * @cap: the capability to allocate the buffer for
1682  * @size: requested size of the buffer
1683  */
1684 static int pci_add_cap_save_buffer(
1685 	struct pci_dev *dev, char cap, unsigned int size)
1686 {
1687 	int pos;
1688 	struct pci_cap_saved_state *save_state;
1689 
1690 	pos = pci_find_capability(dev, cap);
1691 	if (pos <= 0)
1692 		return 0;
1693 
1694 	save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
1695 	if (!save_state)
1696 		return -ENOMEM;
1697 
1698 	save_state->cap_nr = cap;
1699 	pci_add_saved_cap(dev, save_state);
1700 
1701 	return 0;
1702 }
1703 
1704 /**
1705  * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
1706  * @dev: the PCI device
1707  */
1708 void pci_allocate_cap_save_buffers(struct pci_dev *dev)
1709 {
1710 	int error;
1711 
1712 	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
1713 					PCI_EXP_SAVE_REGS * sizeof(u16));
1714 	if (error)
1715 		dev_err(&dev->dev,
1716 			"unable to preallocate PCI Express save buffer\n");
1717 
1718 	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
1719 	if (error)
1720 		dev_err(&dev->dev,
1721 			"unable to preallocate PCI-X save buffer\n");
1722 }
1723 
1724 /**
1725  * pci_enable_ari - enable ARI forwarding if hardware support it
1726  * @dev: the PCI device
1727  */
1728 void pci_enable_ari(struct pci_dev *dev)
1729 {
1730 	int pos;
1731 	u32 cap;
1732 	u16 ctrl;
1733 	struct pci_dev *bridge;
1734 
1735 	if (!pci_is_pcie(dev) || dev->devfn)
1736 		return;
1737 
1738 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1739 	if (!pos)
1740 		return;
1741 
1742 	bridge = dev->bus->self;
1743 	if (!bridge || !pci_is_pcie(bridge))
1744 		return;
1745 
1746 	pos = pci_pcie_cap(bridge);
1747 	if (!pos)
1748 		return;
1749 
1750 	pci_read_config_dword(bridge, pos + PCI_EXP_DEVCAP2, &cap);
1751 	if (!(cap & PCI_EXP_DEVCAP2_ARI))
1752 		return;
1753 
1754 	pci_read_config_word(bridge, pos + PCI_EXP_DEVCTL2, &ctrl);
1755 	ctrl |= PCI_EXP_DEVCTL2_ARI;
1756 	pci_write_config_word(bridge, pos + PCI_EXP_DEVCTL2, ctrl);
1757 
1758 	bridge->ari_enabled = 1;
1759 }
1760 
1761 static int pci_acs_enable;
1762 
1763 /**
1764  * pci_request_acs - ask for ACS to be enabled if supported
1765  */
1766 void pci_request_acs(void)
1767 {
1768 	pci_acs_enable = 1;
1769 }
1770 
1771 /**
1772  * pci_enable_acs - enable ACS if hardware support it
1773  * @dev: the PCI device
1774  */
1775 void pci_enable_acs(struct pci_dev *dev)
1776 {
1777 	int pos;
1778 	u16 cap;
1779 	u16 ctrl;
1780 
1781 	if (!pci_acs_enable)
1782 		return;
1783 
1784 	if (!pci_is_pcie(dev))
1785 		return;
1786 
1787 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
1788 	if (!pos)
1789 		return;
1790 
1791 	pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
1792 	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
1793 
1794 	/* Source Validation */
1795 	ctrl |= (cap & PCI_ACS_SV);
1796 
1797 	/* P2P Request Redirect */
1798 	ctrl |= (cap & PCI_ACS_RR);
1799 
1800 	/* P2P Completion Redirect */
1801 	ctrl |= (cap & PCI_ACS_CR);
1802 
1803 	/* Upstream Forwarding */
1804 	ctrl |= (cap & PCI_ACS_UF);
1805 
1806 	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
1807 }
1808 
1809 /**
1810  * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
1811  * @dev: the PCI device
1812  * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTD, 4=INTD)
1813  *
1814  * Perform INTx swizzling for a device behind one level of bridge.  This is
1815  * required by section 9.1 of the PCI-to-PCI bridge specification for devices
1816  * behind bridges on add-in cards.  For devices with ARI enabled, the slot
1817  * number is always 0 (see the Implementation Note in section 2.2.8.1 of
1818  * the PCI Express Base Specification, Revision 2.1)
1819  */
1820 u8 pci_swizzle_interrupt_pin(struct pci_dev *dev, u8 pin)
1821 {
1822 	int slot;
1823 
1824 	if (pci_ari_enabled(dev->bus))
1825 		slot = 0;
1826 	else
1827 		slot = PCI_SLOT(dev->devfn);
1828 
1829 	return (((pin - 1) + slot) % 4) + 1;
1830 }
1831 
1832 int
1833 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
1834 {
1835 	u8 pin;
1836 
1837 	pin = dev->pin;
1838 	if (!pin)
1839 		return -1;
1840 
1841 	while (!pci_is_root_bus(dev->bus)) {
1842 		pin = pci_swizzle_interrupt_pin(dev, pin);
1843 		dev = dev->bus->self;
1844 	}
1845 	*bridge = dev;
1846 	return pin;
1847 }
1848 
1849 /**
1850  * pci_common_swizzle - swizzle INTx all the way to root bridge
1851  * @dev: the PCI device
1852  * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
1853  *
1854  * Perform INTx swizzling for a device.  This traverses through all PCI-to-PCI
1855  * bridges all the way up to a PCI root bus.
1856  */
1857 u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
1858 {
1859 	u8 pin = *pinp;
1860 
1861 	while (!pci_is_root_bus(dev->bus)) {
1862 		pin = pci_swizzle_interrupt_pin(dev, pin);
1863 		dev = dev->bus->self;
1864 	}
1865 	*pinp = pin;
1866 	return PCI_SLOT(dev->devfn);
1867 }
1868 
1869 /**
1870  *	pci_release_region - Release a PCI bar
1871  *	@pdev: PCI device whose resources were previously reserved by pci_request_region
1872  *	@bar: BAR to release
1873  *
1874  *	Releases the PCI I/O and memory resources previously reserved by a
1875  *	successful call to pci_request_region.  Call this function only
1876  *	after all use of the PCI regions has ceased.
1877  */
1878 void pci_release_region(struct pci_dev *pdev, int bar)
1879 {
1880 	struct pci_devres *dr;
1881 
1882 	if (pci_resource_len(pdev, bar) == 0)
1883 		return;
1884 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1885 		release_region(pci_resource_start(pdev, bar),
1886 				pci_resource_len(pdev, bar));
1887 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1888 		release_mem_region(pci_resource_start(pdev, bar),
1889 				pci_resource_len(pdev, bar));
1890 
1891 	dr = find_pci_dr(pdev);
1892 	if (dr)
1893 		dr->region_mask &= ~(1 << bar);
1894 }
1895 
1896 /**
1897  *	__pci_request_region - Reserved PCI I/O and memory resource
1898  *	@pdev: PCI device whose resources are to be reserved
1899  *	@bar: BAR to be reserved
1900  *	@res_name: Name to be associated with resource.
1901  *	@exclusive: whether the region access is exclusive or not
1902  *
1903  *	Mark the PCI region associated with PCI device @pdev BR @bar as
1904  *	being reserved by owner @res_name.  Do not access any
1905  *	address inside the PCI regions unless this call returns
1906  *	successfully.
1907  *
1908  *	If @exclusive is set, then the region is marked so that userspace
1909  *	is explicitly not allowed to map the resource via /dev/mem or
1910  * 	sysfs MMIO access.
1911  *
1912  *	Returns 0 on success, or %EBUSY on error.  A warning
1913  *	message is also printed on failure.
1914  */
1915 static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
1916 									int exclusive)
1917 {
1918 	struct pci_devres *dr;
1919 
1920 	if (pci_resource_len(pdev, bar) == 0)
1921 		return 0;
1922 
1923 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1924 		if (!request_region(pci_resource_start(pdev, bar),
1925 			    pci_resource_len(pdev, bar), res_name))
1926 			goto err_out;
1927 	}
1928 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1929 		if (!__request_mem_region(pci_resource_start(pdev, bar),
1930 					pci_resource_len(pdev, bar), res_name,
1931 					exclusive))
1932 			goto err_out;
1933 	}
1934 
1935 	dr = find_pci_dr(pdev);
1936 	if (dr)
1937 		dr->region_mask |= 1 << bar;
1938 
1939 	return 0;
1940 
1941 err_out:
1942 	dev_warn(&pdev->dev, "BAR %d: can't reserve %pR\n", bar,
1943 		 &pdev->resource[bar]);
1944 	return -EBUSY;
1945 }
1946 
1947 /**
1948  *	pci_request_region - Reserve PCI I/O and memory resource
1949  *	@pdev: PCI device whose resources are to be reserved
1950  *	@bar: BAR to be reserved
1951  *	@res_name: Name to be associated with resource
1952  *
1953  *	Mark the PCI region associated with PCI device @pdev BAR @bar as
1954  *	being reserved by owner @res_name.  Do not access any
1955  *	address inside the PCI regions unless this call returns
1956  *	successfully.
1957  *
1958  *	Returns 0 on success, or %EBUSY on error.  A warning
1959  *	message is also printed on failure.
1960  */
1961 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1962 {
1963 	return __pci_request_region(pdev, bar, res_name, 0);
1964 }
1965 
1966 /**
1967  *	pci_request_region_exclusive - Reserved PCI I/O and memory resource
1968  *	@pdev: PCI device whose resources are to be reserved
1969  *	@bar: BAR to be reserved
1970  *	@res_name: Name to be associated with resource.
1971  *
1972  *	Mark the PCI region associated with PCI device @pdev BR @bar as
1973  *	being reserved by owner @res_name.  Do not access any
1974  *	address inside the PCI regions unless this call returns
1975  *	successfully.
1976  *
1977  *	Returns 0 on success, or %EBUSY on error.  A warning
1978  *	message is also printed on failure.
1979  *
1980  *	The key difference that _exclusive makes it that userspace is
1981  *	explicitly not allowed to map the resource via /dev/mem or
1982  * 	sysfs.
1983  */
1984 int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name)
1985 {
1986 	return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
1987 }
1988 /**
1989  * pci_release_selected_regions - Release selected PCI I/O and memory resources
1990  * @pdev: PCI device whose resources were previously reserved
1991  * @bars: Bitmask of BARs to be released
1992  *
1993  * Release selected PCI I/O and memory resources previously reserved.
1994  * Call this function only after all use of the PCI regions has ceased.
1995  */
1996 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1997 {
1998 	int i;
1999 
2000 	for (i = 0; i < 6; i++)
2001 		if (bars & (1 << i))
2002 			pci_release_region(pdev, i);
2003 }
2004 
2005 int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
2006 				 const char *res_name, int excl)
2007 {
2008 	int i;
2009 
2010 	for (i = 0; i < 6; i++)
2011 		if (bars & (1 << i))
2012 			if (__pci_request_region(pdev, i, res_name, excl))
2013 				goto err_out;
2014 	return 0;
2015 
2016 err_out:
2017 	while(--i >= 0)
2018 		if (bars & (1 << i))
2019 			pci_release_region(pdev, i);
2020 
2021 	return -EBUSY;
2022 }
2023 
2024 
2025 /**
2026  * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
2027  * @pdev: PCI device whose resources are to be reserved
2028  * @bars: Bitmask of BARs to be requested
2029  * @res_name: Name to be associated with resource
2030  */
2031 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
2032 				 const char *res_name)
2033 {
2034 	return __pci_request_selected_regions(pdev, bars, res_name, 0);
2035 }
2036 
2037 int pci_request_selected_regions_exclusive(struct pci_dev *pdev,
2038 				 int bars, const char *res_name)
2039 {
2040 	return __pci_request_selected_regions(pdev, bars, res_name,
2041 			IORESOURCE_EXCLUSIVE);
2042 }
2043 
2044 /**
2045  *	pci_release_regions - Release reserved PCI I/O and memory resources
2046  *	@pdev: PCI device whose resources were previously reserved by pci_request_regions
2047  *
2048  *	Releases all PCI I/O and memory resources previously reserved by a
2049  *	successful call to pci_request_regions.  Call this function only
2050  *	after all use of the PCI regions has ceased.
2051  */
2052 
2053 void pci_release_regions(struct pci_dev *pdev)
2054 {
2055 	pci_release_selected_regions(pdev, (1 << 6) - 1);
2056 }
2057 
2058 /**
2059  *	pci_request_regions - Reserved PCI I/O and memory resources
2060  *	@pdev: PCI device whose resources are to be reserved
2061  *	@res_name: Name to be associated with resource.
2062  *
2063  *	Mark all PCI regions associated with PCI device @pdev as
2064  *	being reserved by owner @res_name.  Do not access any
2065  *	address inside the PCI regions unless this call returns
2066  *	successfully.
2067  *
2068  *	Returns 0 on success, or %EBUSY on error.  A warning
2069  *	message is also printed on failure.
2070  */
2071 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
2072 {
2073 	return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
2074 }
2075 
2076 /**
2077  *	pci_request_regions_exclusive - Reserved PCI I/O and memory resources
2078  *	@pdev: PCI device whose resources are to be reserved
2079  *	@res_name: Name to be associated with resource.
2080  *
2081  *	Mark all PCI regions associated with PCI device @pdev as
2082  *	being reserved by owner @res_name.  Do not access any
2083  *	address inside the PCI regions unless this call returns
2084  *	successfully.
2085  *
2086  *	pci_request_regions_exclusive() will mark the region so that
2087  * 	/dev/mem and the sysfs MMIO access will not be allowed.
2088  *
2089  *	Returns 0 on success, or %EBUSY on error.  A warning
2090  *	message is also printed on failure.
2091  */
2092 int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
2093 {
2094 	return pci_request_selected_regions_exclusive(pdev,
2095 					((1 << 6) - 1), res_name);
2096 }
2097 
2098 static void __pci_set_master(struct pci_dev *dev, bool enable)
2099 {
2100 	u16 old_cmd, cmd;
2101 
2102 	pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
2103 	if (enable)
2104 		cmd = old_cmd | PCI_COMMAND_MASTER;
2105 	else
2106 		cmd = old_cmd & ~PCI_COMMAND_MASTER;
2107 	if (cmd != old_cmd) {
2108 		dev_dbg(&dev->dev, "%s bus mastering\n",
2109 			enable ? "enabling" : "disabling");
2110 		pci_write_config_word(dev, PCI_COMMAND, cmd);
2111 	}
2112 	dev->is_busmaster = enable;
2113 }
2114 
2115 /**
2116  * pci_set_master - enables bus-mastering for device dev
2117  * @dev: the PCI device to enable
2118  *
2119  * Enables bus-mastering on the device and calls pcibios_set_master()
2120  * to do the needed arch specific settings.
2121  */
2122 void pci_set_master(struct pci_dev *dev)
2123 {
2124 	__pci_set_master(dev, true);
2125 	pcibios_set_master(dev);
2126 }
2127 
2128 /**
2129  * pci_clear_master - disables bus-mastering for device dev
2130  * @dev: the PCI device to disable
2131  */
2132 void pci_clear_master(struct pci_dev *dev)
2133 {
2134 	__pci_set_master(dev, false);
2135 }
2136 
2137 /**
2138  * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
2139  * @dev: the PCI device for which MWI is to be enabled
2140  *
2141  * Helper function for pci_set_mwi.
2142  * Originally copied from drivers/net/acenic.c.
2143  * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
2144  *
2145  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2146  */
2147 int pci_set_cacheline_size(struct pci_dev *dev)
2148 {
2149 	u8 cacheline_size;
2150 
2151 	if (!pci_cache_line_size)
2152 		return -EINVAL;
2153 
2154 	/* Validate current setting: the PCI_CACHE_LINE_SIZE must be
2155 	   equal to or multiple of the right value. */
2156 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2157 	if (cacheline_size >= pci_cache_line_size &&
2158 	    (cacheline_size % pci_cache_line_size) == 0)
2159 		return 0;
2160 
2161 	/* Write the correct value. */
2162 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
2163 	/* Read it back. */
2164 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2165 	if (cacheline_size == pci_cache_line_size)
2166 		return 0;
2167 
2168 	dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
2169 		   "supported\n", pci_cache_line_size << 2);
2170 
2171 	return -EINVAL;
2172 }
2173 EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
2174 
2175 #ifdef PCI_DISABLE_MWI
2176 int pci_set_mwi(struct pci_dev *dev)
2177 {
2178 	return 0;
2179 }
2180 
2181 int pci_try_set_mwi(struct pci_dev *dev)
2182 {
2183 	return 0;
2184 }
2185 
2186 void pci_clear_mwi(struct pci_dev *dev)
2187 {
2188 }
2189 
2190 #else
2191 
2192 /**
2193  * pci_set_mwi - enables memory-write-invalidate PCI transaction
2194  * @dev: the PCI device for which MWI is enabled
2195  *
2196  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2197  *
2198  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2199  */
2200 int
2201 pci_set_mwi(struct pci_dev *dev)
2202 {
2203 	int rc;
2204 	u16 cmd;
2205 
2206 	rc = pci_set_cacheline_size(dev);
2207 	if (rc)
2208 		return rc;
2209 
2210 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2211 	if (! (cmd & PCI_COMMAND_INVALIDATE)) {
2212 		dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
2213 		cmd |= PCI_COMMAND_INVALIDATE;
2214 		pci_write_config_word(dev, PCI_COMMAND, cmd);
2215 	}
2216 
2217 	return 0;
2218 }
2219 
2220 /**
2221  * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
2222  * @dev: the PCI device for which MWI is enabled
2223  *
2224  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2225  * Callers are not required to check the return value.
2226  *
2227  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2228  */
2229 int pci_try_set_mwi(struct pci_dev *dev)
2230 {
2231 	int rc = pci_set_mwi(dev);
2232 	return rc;
2233 }
2234 
2235 /**
2236  * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
2237  * @dev: the PCI device to disable
2238  *
2239  * Disables PCI Memory-Write-Invalidate transaction on the device
2240  */
2241 void
2242 pci_clear_mwi(struct pci_dev *dev)
2243 {
2244 	u16 cmd;
2245 
2246 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2247 	if (cmd & PCI_COMMAND_INVALIDATE) {
2248 		cmd &= ~PCI_COMMAND_INVALIDATE;
2249 		pci_write_config_word(dev, PCI_COMMAND, cmd);
2250 	}
2251 }
2252 #endif /* ! PCI_DISABLE_MWI */
2253 
2254 /**
2255  * pci_intx - enables/disables PCI INTx for device dev
2256  * @pdev: the PCI device to operate on
2257  * @enable: boolean: whether to enable or disable PCI INTx
2258  *
2259  * Enables/disables PCI INTx for device dev
2260  */
2261 void
2262 pci_intx(struct pci_dev *pdev, int enable)
2263 {
2264 	u16 pci_command, new;
2265 
2266 	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
2267 
2268 	if (enable) {
2269 		new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
2270 	} else {
2271 		new = pci_command | PCI_COMMAND_INTX_DISABLE;
2272 	}
2273 
2274 	if (new != pci_command) {
2275 		struct pci_devres *dr;
2276 
2277 		pci_write_config_word(pdev, PCI_COMMAND, new);
2278 
2279 		dr = find_pci_dr(pdev);
2280 		if (dr && !dr->restore_intx) {
2281 			dr->restore_intx = 1;
2282 			dr->orig_intx = !enable;
2283 		}
2284 	}
2285 }
2286 
2287 /**
2288  * pci_msi_off - disables any msi or msix capabilities
2289  * @dev: the PCI device to operate on
2290  *
2291  * If you want to use msi see pci_enable_msi and friends.
2292  * This is a lower level primitive that allows us to disable
2293  * msi operation at the device level.
2294  */
2295 void pci_msi_off(struct pci_dev *dev)
2296 {
2297 	int pos;
2298 	u16 control;
2299 
2300 	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
2301 	if (pos) {
2302 		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
2303 		control &= ~PCI_MSI_FLAGS_ENABLE;
2304 		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
2305 	}
2306 	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
2307 	if (pos) {
2308 		pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
2309 		control &= ~PCI_MSIX_FLAGS_ENABLE;
2310 		pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
2311 	}
2312 }
2313 EXPORT_SYMBOL_GPL(pci_msi_off);
2314 
2315 int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
2316 {
2317 	return dma_set_max_seg_size(&dev->dev, size);
2318 }
2319 EXPORT_SYMBOL(pci_set_dma_max_seg_size);
2320 
2321 int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
2322 {
2323 	return dma_set_seg_boundary(&dev->dev, mask);
2324 }
2325 EXPORT_SYMBOL(pci_set_dma_seg_boundary);
2326 
2327 static int pcie_flr(struct pci_dev *dev, int probe)
2328 {
2329 	int i;
2330 	int pos;
2331 	u32 cap;
2332 	u16 status, control;
2333 
2334 	pos = pci_pcie_cap(dev);
2335 	if (!pos)
2336 		return -ENOTTY;
2337 
2338 	pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP, &cap);
2339 	if (!(cap & PCI_EXP_DEVCAP_FLR))
2340 		return -ENOTTY;
2341 
2342 	if (probe)
2343 		return 0;
2344 
2345 	/* Wait for Transaction Pending bit clean */
2346 	for (i = 0; i < 4; i++) {
2347 		if (i)
2348 			msleep((1 << (i - 1)) * 100);
2349 
2350 		pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &status);
2351 		if (!(status & PCI_EXP_DEVSTA_TRPND))
2352 			goto clear;
2353 	}
2354 
2355 	dev_err(&dev->dev, "transaction is not cleared; "
2356 			"proceeding with reset anyway\n");
2357 
2358 clear:
2359 	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &control);
2360 	control |= PCI_EXP_DEVCTL_BCR_FLR;
2361 	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, control);
2362 
2363 	msleep(100);
2364 
2365 	return 0;
2366 }
2367 
2368 static int pci_af_flr(struct pci_dev *dev, int probe)
2369 {
2370 	int i;
2371 	int pos;
2372 	u8 cap;
2373 	u8 status;
2374 
2375 	pos = pci_find_capability(dev, PCI_CAP_ID_AF);
2376 	if (!pos)
2377 		return -ENOTTY;
2378 
2379 	pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
2380 	if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
2381 		return -ENOTTY;
2382 
2383 	if (probe)
2384 		return 0;
2385 
2386 	/* Wait for Transaction Pending bit clean */
2387 	for (i = 0; i < 4; i++) {
2388 		if (i)
2389 			msleep((1 << (i - 1)) * 100);
2390 
2391 		pci_read_config_byte(dev, pos + PCI_AF_STATUS, &status);
2392 		if (!(status & PCI_AF_STATUS_TP))
2393 			goto clear;
2394 	}
2395 
2396 	dev_err(&dev->dev, "transaction is not cleared; "
2397 			"proceeding with reset anyway\n");
2398 
2399 clear:
2400 	pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
2401 	msleep(100);
2402 
2403 	return 0;
2404 }
2405 
2406 static int pci_pm_reset(struct pci_dev *dev, int probe)
2407 {
2408 	u16 csr;
2409 
2410 	if (!dev->pm_cap)
2411 		return -ENOTTY;
2412 
2413 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
2414 	if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
2415 		return -ENOTTY;
2416 
2417 	if (probe)
2418 		return 0;
2419 
2420 	if (dev->current_state != PCI_D0)
2421 		return -EINVAL;
2422 
2423 	csr &= ~PCI_PM_CTRL_STATE_MASK;
2424 	csr |= PCI_D3hot;
2425 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
2426 	pci_dev_d3_sleep(dev);
2427 
2428 	csr &= ~PCI_PM_CTRL_STATE_MASK;
2429 	csr |= PCI_D0;
2430 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
2431 	pci_dev_d3_sleep(dev);
2432 
2433 	return 0;
2434 }
2435 
2436 static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
2437 {
2438 	u16 ctrl;
2439 	struct pci_dev *pdev;
2440 
2441 	if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self)
2442 		return -ENOTTY;
2443 
2444 	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
2445 		if (pdev != dev)
2446 			return -ENOTTY;
2447 
2448 	if (probe)
2449 		return 0;
2450 
2451 	pci_read_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, &ctrl);
2452 	ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
2453 	pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
2454 	msleep(100);
2455 
2456 	ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
2457 	pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
2458 	msleep(100);
2459 
2460 	return 0;
2461 }
2462 
2463 static int pci_dev_reset(struct pci_dev *dev, int probe)
2464 {
2465 	int rc;
2466 
2467 	might_sleep();
2468 
2469 	if (!probe) {
2470 		pci_block_user_cfg_access(dev);
2471 		/* block PM suspend, driver probe, etc. */
2472 		device_lock(&dev->dev);
2473 	}
2474 
2475 	rc = pci_dev_specific_reset(dev, probe);
2476 	if (rc != -ENOTTY)
2477 		goto done;
2478 
2479 	rc = pcie_flr(dev, probe);
2480 	if (rc != -ENOTTY)
2481 		goto done;
2482 
2483 	rc = pci_af_flr(dev, probe);
2484 	if (rc != -ENOTTY)
2485 		goto done;
2486 
2487 	rc = pci_pm_reset(dev, probe);
2488 	if (rc != -ENOTTY)
2489 		goto done;
2490 
2491 	rc = pci_parent_bus_reset(dev, probe);
2492 done:
2493 	if (!probe) {
2494 		device_unlock(&dev->dev);
2495 		pci_unblock_user_cfg_access(dev);
2496 	}
2497 
2498 	return rc;
2499 }
2500 
2501 /**
2502  * __pci_reset_function - reset a PCI device function
2503  * @dev: PCI device to reset
2504  *
2505  * Some devices allow an individual function to be reset without affecting
2506  * other functions in the same device.  The PCI device must be responsive
2507  * to PCI config space in order to use this function.
2508  *
2509  * The device function is presumed to be unused when this function is called.
2510  * Resetting the device will make the contents of PCI configuration space
2511  * random, so any caller of this must be prepared to reinitialise the
2512  * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
2513  * etc.
2514  *
2515  * Returns 0 if the device function was successfully reset or negative if the
2516  * device doesn't support resetting a single function.
2517  */
2518 int __pci_reset_function(struct pci_dev *dev)
2519 {
2520 	return pci_dev_reset(dev, 0);
2521 }
2522 EXPORT_SYMBOL_GPL(__pci_reset_function);
2523 
2524 /**
2525  * pci_probe_reset_function - check whether the device can be safely reset
2526  * @dev: PCI device to reset
2527  *
2528  * Some devices allow an individual function to be reset without affecting
2529  * other functions in the same device.  The PCI device must be responsive
2530  * to PCI config space in order to use this function.
2531  *
2532  * Returns 0 if the device function can be reset or negative if the
2533  * device doesn't support resetting a single function.
2534  */
2535 int pci_probe_reset_function(struct pci_dev *dev)
2536 {
2537 	return pci_dev_reset(dev, 1);
2538 }
2539 
2540 /**
2541  * pci_reset_function - quiesce and reset a PCI device function
2542  * @dev: PCI device to reset
2543  *
2544  * Some devices allow an individual function to be reset without affecting
2545  * other functions in the same device.  The PCI device must be responsive
2546  * to PCI config space in order to use this function.
2547  *
2548  * This function does not just reset the PCI portion of a device, but
2549  * clears all the state associated with the device.  This function differs
2550  * from __pci_reset_function in that it saves and restores device state
2551  * over the reset.
2552  *
2553  * Returns 0 if the device function was successfully reset or negative if the
2554  * device doesn't support resetting a single function.
2555  */
2556 int pci_reset_function(struct pci_dev *dev)
2557 {
2558 	int rc;
2559 
2560 	rc = pci_dev_reset(dev, 1);
2561 	if (rc)
2562 		return rc;
2563 
2564 	pci_save_state(dev);
2565 
2566 	/*
2567 	 * both INTx and MSI are disabled after the Interrupt Disable bit
2568 	 * is set and the Bus Master bit is cleared.
2569 	 */
2570 	pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
2571 
2572 	rc = pci_dev_reset(dev, 0);
2573 
2574 	pci_restore_state(dev);
2575 
2576 	return rc;
2577 }
2578 EXPORT_SYMBOL_GPL(pci_reset_function);
2579 
2580 /**
2581  * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
2582  * @dev: PCI device to query
2583  *
2584  * Returns mmrbc: maximum designed memory read count in bytes
2585  *    or appropriate error value.
2586  */
2587 int pcix_get_max_mmrbc(struct pci_dev *dev)
2588 {
2589 	int cap;
2590 	u32 stat;
2591 
2592 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2593 	if (!cap)
2594 		return -EINVAL;
2595 
2596 	if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
2597 		return -EINVAL;
2598 
2599 	return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21);
2600 }
2601 EXPORT_SYMBOL(pcix_get_max_mmrbc);
2602 
2603 /**
2604  * pcix_get_mmrbc - get PCI-X maximum memory read byte count
2605  * @dev: PCI device to query
2606  *
2607  * Returns mmrbc: maximum memory read count in bytes
2608  *    or appropriate error value.
2609  */
2610 int pcix_get_mmrbc(struct pci_dev *dev)
2611 {
2612 	int cap;
2613 	u16 cmd;
2614 
2615 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2616 	if (!cap)
2617 		return -EINVAL;
2618 
2619 	if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
2620 		return -EINVAL;
2621 
2622 	return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
2623 }
2624 EXPORT_SYMBOL(pcix_get_mmrbc);
2625 
2626 /**
2627  * pcix_set_mmrbc - set PCI-X maximum memory read byte count
2628  * @dev: PCI device to query
2629  * @mmrbc: maximum memory read count in bytes
2630  *    valid values are 512, 1024, 2048, 4096
2631  *
2632  * If possible sets maximum memory read byte count, some bridges have erratas
2633  * that prevent this.
2634  */
2635 int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
2636 {
2637 	int cap;
2638 	u32 stat, v, o;
2639 	u16 cmd;
2640 
2641 	if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
2642 		return -EINVAL;
2643 
2644 	v = ffs(mmrbc) - 10;
2645 
2646 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2647 	if (!cap)
2648 		return -EINVAL;
2649 
2650 	if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
2651 		return -EINVAL;
2652 
2653 	if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
2654 		return -E2BIG;
2655 
2656 	if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
2657 		return -EINVAL;
2658 
2659 	o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
2660 	if (o != v) {
2661 		if (v > o && dev->bus &&
2662 		   (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
2663 			return -EIO;
2664 
2665 		cmd &= ~PCI_X_CMD_MAX_READ;
2666 		cmd |= v << 2;
2667 		if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd))
2668 			return -EIO;
2669 	}
2670 	return 0;
2671 }
2672 EXPORT_SYMBOL(pcix_set_mmrbc);
2673 
2674 /**
2675  * pcie_get_readrq - get PCI Express read request size
2676  * @dev: PCI device to query
2677  *
2678  * Returns maximum memory read request in bytes
2679  *    or appropriate error value.
2680  */
2681 int pcie_get_readrq(struct pci_dev *dev)
2682 {
2683 	int ret, cap;
2684 	u16 ctl;
2685 
2686 	cap = pci_pcie_cap(dev);
2687 	if (!cap)
2688 		return -EINVAL;
2689 
2690 	ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
2691 	if (!ret)
2692 	ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
2693 
2694 	return ret;
2695 }
2696 EXPORT_SYMBOL(pcie_get_readrq);
2697 
2698 /**
2699  * pcie_set_readrq - set PCI Express maximum memory read request
2700  * @dev: PCI device to query
2701  * @rq: maximum memory read count in bytes
2702  *    valid values are 128, 256, 512, 1024, 2048, 4096
2703  *
2704  * If possible sets maximum read byte count
2705  */
2706 int pcie_set_readrq(struct pci_dev *dev, int rq)
2707 {
2708 	int cap, err = -EINVAL;
2709 	u16 ctl, v;
2710 
2711 	if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
2712 		goto out;
2713 
2714 	v = (ffs(rq) - 8) << 12;
2715 
2716 	cap = pci_pcie_cap(dev);
2717 	if (!cap)
2718 		goto out;
2719 
2720 	err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
2721 	if (err)
2722 		goto out;
2723 
2724 	if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
2725 		ctl &= ~PCI_EXP_DEVCTL_READRQ;
2726 		ctl |= v;
2727 		err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
2728 	}
2729 
2730 out:
2731 	return err;
2732 }
2733 EXPORT_SYMBOL(pcie_set_readrq);
2734 
2735 /**
2736  * pci_select_bars - Make BAR mask from the type of resource
2737  * @dev: the PCI device for which BAR mask is made
2738  * @flags: resource type mask to be selected
2739  *
2740  * This helper routine makes bar mask from the type of resource.
2741  */
2742 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
2743 {
2744 	int i, bars = 0;
2745 	for (i = 0; i < PCI_NUM_RESOURCES; i++)
2746 		if (pci_resource_flags(dev, i) & flags)
2747 			bars |= (1 << i);
2748 	return bars;
2749 }
2750 
2751 /**
2752  * pci_resource_bar - get position of the BAR associated with a resource
2753  * @dev: the PCI device
2754  * @resno: the resource number
2755  * @type: the BAR type to be filled in
2756  *
2757  * Returns BAR position in config space, or 0 if the BAR is invalid.
2758  */
2759 int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type)
2760 {
2761 	int reg;
2762 
2763 	if (resno < PCI_ROM_RESOURCE) {
2764 		*type = pci_bar_unknown;
2765 		return PCI_BASE_ADDRESS_0 + 4 * resno;
2766 	} else if (resno == PCI_ROM_RESOURCE) {
2767 		*type = pci_bar_mem32;
2768 		return dev->rom_base_reg;
2769 	} else if (resno < PCI_BRIDGE_RESOURCES) {
2770 		/* device specific resource */
2771 		reg = pci_iov_resource_bar(dev, resno, type);
2772 		if (reg)
2773 			return reg;
2774 	}
2775 
2776 	dev_err(&dev->dev, "BAR %d: invalid resource\n", resno);
2777 	return 0;
2778 }
2779 
2780 /* Some architectures require additional programming to enable VGA */
2781 static arch_set_vga_state_t arch_set_vga_state;
2782 
2783 void __init pci_register_set_vga_state(arch_set_vga_state_t func)
2784 {
2785 	arch_set_vga_state = func;	/* NULL disables */
2786 }
2787 
2788 static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode,
2789 		      unsigned int command_bits, bool change_bridge)
2790 {
2791 	if (arch_set_vga_state)
2792 		return arch_set_vga_state(dev, decode, command_bits,
2793 						change_bridge);
2794 	return 0;
2795 }
2796 
2797 /**
2798  * pci_set_vga_state - set VGA decode state on device and parents if requested
2799  * @dev: the PCI device
2800  * @decode: true = enable decoding, false = disable decoding
2801  * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
2802  * @change_bridge: traverse ancestors and change bridges
2803  */
2804 int pci_set_vga_state(struct pci_dev *dev, bool decode,
2805 		      unsigned int command_bits, bool change_bridge)
2806 {
2807 	struct pci_bus *bus;
2808 	struct pci_dev *bridge;
2809 	u16 cmd;
2810 	int rc;
2811 
2812 	WARN_ON(command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY));
2813 
2814 	/* ARCH specific VGA enables */
2815 	rc = pci_set_vga_state_arch(dev, decode, command_bits, change_bridge);
2816 	if (rc)
2817 		return rc;
2818 
2819 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2820 	if (decode == true)
2821 		cmd |= command_bits;
2822 	else
2823 		cmd &= ~command_bits;
2824 	pci_write_config_word(dev, PCI_COMMAND, cmd);
2825 
2826 	if (change_bridge == false)
2827 		return 0;
2828 
2829 	bus = dev->bus;
2830 	while (bus) {
2831 		bridge = bus->self;
2832 		if (bridge) {
2833 			pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
2834 					     &cmd);
2835 			if (decode == true)
2836 				cmd |= PCI_BRIDGE_CTL_VGA;
2837 			else
2838 				cmd &= ~PCI_BRIDGE_CTL_VGA;
2839 			pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
2840 					      cmd);
2841 		}
2842 		bus = bus->parent;
2843 	}
2844 	return 0;
2845 }
2846 
2847 #define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
2848 static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
2849 static DEFINE_SPINLOCK(resource_alignment_lock);
2850 
2851 /**
2852  * pci_specified_resource_alignment - get resource alignment specified by user.
2853  * @dev: the PCI device to get
2854  *
2855  * RETURNS: Resource alignment if it is specified.
2856  *          Zero if it is not specified.
2857  */
2858 resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
2859 {
2860 	int seg, bus, slot, func, align_order, count;
2861 	resource_size_t align = 0;
2862 	char *p;
2863 
2864 	spin_lock(&resource_alignment_lock);
2865 	p = resource_alignment_param;
2866 	while (*p) {
2867 		count = 0;
2868 		if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
2869 							p[count] == '@') {
2870 			p += count + 1;
2871 		} else {
2872 			align_order = -1;
2873 		}
2874 		if (sscanf(p, "%x:%x:%x.%x%n",
2875 			&seg, &bus, &slot, &func, &count) != 4) {
2876 			seg = 0;
2877 			if (sscanf(p, "%x:%x.%x%n",
2878 					&bus, &slot, &func, &count) != 3) {
2879 				/* Invalid format */
2880 				printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
2881 					p);
2882 				break;
2883 			}
2884 		}
2885 		p += count;
2886 		if (seg == pci_domain_nr(dev->bus) &&
2887 			bus == dev->bus->number &&
2888 			slot == PCI_SLOT(dev->devfn) &&
2889 			func == PCI_FUNC(dev->devfn)) {
2890 			if (align_order == -1) {
2891 				align = PAGE_SIZE;
2892 			} else {
2893 				align = 1 << align_order;
2894 			}
2895 			/* Found */
2896 			break;
2897 		}
2898 		if (*p != ';' && *p != ',') {
2899 			/* End of param or invalid format */
2900 			break;
2901 		}
2902 		p++;
2903 	}
2904 	spin_unlock(&resource_alignment_lock);
2905 	return align;
2906 }
2907 
2908 /**
2909  * pci_is_reassigndev - check if specified PCI is target device to reassign
2910  * @dev: the PCI device to check
2911  *
2912  * RETURNS: non-zero for PCI device is a target device to reassign,
2913  *          or zero is not.
2914  */
2915 int pci_is_reassigndev(struct pci_dev *dev)
2916 {
2917 	return (pci_specified_resource_alignment(dev) != 0);
2918 }
2919 
2920 ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
2921 {
2922 	if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
2923 		count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
2924 	spin_lock(&resource_alignment_lock);
2925 	strncpy(resource_alignment_param, buf, count);
2926 	resource_alignment_param[count] = '\0';
2927 	spin_unlock(&resource_alignment_lock);
2928 	return count;
2929 }
2930 
2931 ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
2932 {
2933 	size_t count;
2934 	spin_lock(&resource_alignment_lock);
2935 	count = snprintf(buf, size, "%s", resource_alignment_param);
2936 	spin_unlock(&resource_alignment_lock);
2937 	return count;
2938 }
2939 
2940 static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
2941 {
2942 	return pci_get_resource_alignment_param(buf, PAGE_SIZE);
2943 }
2944 
2945 static ssize_t pci_resource_alignment_store(struct bus_type *bus,
2946 					const char *buf, size_t count)
2947 {
2948 	return pci_set_resource_alignment_param(buf, count);
2949 }
2950 
2951 BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
2952 					pci_resource_alignment_store);
2953 
2954 static int __init pci_resource_alignment_sysfs_init(void)
2955 {
2956 	return bus_create_file(&pci_bus_type,
2957 					&bus_attr_resource_alignment);
2958 }
2959 
2960 late_initcall(pci_resource_alignment_sysfs_init);
2961 
2962 static void __devinit pci_no_domains(void)
2963 {
2964 #ifdef CONFIG_PCI_DOMAINS
2965 	pci_domains_supported = 0;
2966 #endif
2967 }
2968 
2969 /**
2970  * pci_ext_cfg_enabled - can we access extended PCI config space?
2971  * @dev: The PCI device of the root bridge.
2972  *
2973  * Returns 1 if we can access PCI extended config space (offsets
2974  * greater than 0xff). This is the default implementation. Architecture
2975  * implementations can override this.
2976  */
2977 int __attribute__ ((weak)) pci_ext_cfg_avail(struct pci_dev *dev)
2978 {
2979 	return 1;
2980 }
2981 
2982 void __weak pci_fixup_cardbus(struct pci_bus *bus)
2983 {
2984 }
2985 EXPORT_SYMBOL(pci_fixup_cardbus);
2986 
2987 static int __init pci_setup(char *str)
2988 {
2989 	while (str) {
2990 		char *k = strchr(str, ',');
2991 		if (k)
2992 			*k++ = 0;
2993 		if (*str && (str = pcibios_setup(str)) && *str) {
2994 			if (!strcmp(str, "nomsi")) {
2995 				pci_no_msi();
2996 			} else if (!strcmp(str, "noaer")) {
2997 				pci_no_aer();
2998 			} else if (!strcmp(str, "nodomains")) {
2999 				pci_no_domains();
3000 			} else if (!strncmp(str, "cbiosize=", 9)) {
3001 				pci_cardbus_io_size = memparse(str + 9, &str);
3002 			} else if (!strncmp(str, "cbmemsize=", 10)) {
3003 				pci_cardbus_mem_size = memparse(str + 10, &str);
3004 			} else if (!strncmp(str, "resource_alignment=", 19)) {
3005 				pci_set_resource_alignment_param(str + 19,
3006 							strlen(str + 19));
3007 			} else if (!strncmp(str, "ecrc=", 5)) {
3008 				pcie_ecrc_get_policy(str + 5);
3009 			} else if (!strncmp(str, "hpiosize=", 9)) {
3010 				pci_hotplug_io_size = memparse(str + 9, &str);
3011 			} else if (!strncmp(str, "hpmemsize=", 10)) {
3012 				pci_hotplug_mem_size = memparse(str + 10, &str);
3013 			} else {
3014 				printk(KERN_ERR "PCI: Unknown option `%s'\n",
3015 						str);
3016 			}
3017 		}
3018 		str = k;
3019 	}
3020 	return 0;
3021 }
3022 early_param("pci", pci_setup);
3023 
3024 EXPORT_SYMBOL(pci_reenable_device);
3025 EXPORT_SYMBOL(pci_enable_device_io);
3026 EXPORT_SYMBOL(pci_enable_device_mem);
3027 EXPORT_SYMBOL(pci_enable_device);
3028 EXPORT_SYMBOL(pcim_enable_device);
3029 EXPORT_SYMBOL(pcim_pin_device);
3030 EXPORT_SYMBOL(pci_disable_device);
3031 EXPORT_SYMBOL(pci_find_capability);
3032 EXPORT_SYMBOL(pci_bus_find_capability);
3033 EXPORT_SYMBOL(pci_release_regions);
3034 EXPORT_SYMBOL(pci_request_regions);
3035 EXPORT_SYMBOL(pci_request_regions_exclusive);
3036 EXPORT_SYMBOL(pci_release_region);
3037 EXPORT_SYMBOL(pci_request_region);
3038 EXPORT_SYMBOL(pci_request_region_exclusive);
3039 EXPORT_SYMBOL(pci_release_selected_regions);
3040 EXPORT_SYMBOL(pci_request_selected_regions);
3041 EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
3042 EXPORT_SYMBOL(pci_set_master);
3043 EXPORT_SYMBOL(pci_clear_master);
3044 EXPORT_SYMBOL(pci_set_mwi);
3045 EXPORT_SYMBOL(pci_try_set_mwi);
3046 EXPORT_SYMBOL(pci_clear_mwi);
3047 EXPORT_SYMBOL_GPL(pci_intx);
3048 EXPORT_SYMBOL(pci_assign_resource);
3049 EXPORT_SYMBOL(pci_find_parent_resource);
3050 EXPORT_SYMBOL(pci_select_bars);
3051 
3052 EXPORT_SYMBOL(pci_set_power_state);
3053 EXPORT_SYMBOL(pci_save_state);
3054 EXPORT_SYMBOL(pci_restore_state);
3055 EXPORT_SYMBOL(pci_pme_capable);
3056 EXPORT_SYMBOL(pci_pme_active);
3057 EXPORT_SYMBOL(pci_wake_from_d3);
3058 EXPORT_SYMBOL(pci_target_state);
3059 EXPORT_SYMBOL(pci_prepare_to_sleep);
3060 EXPORT_SYMBOL(pci_back_from_sleep);
3061 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
3062