xref: /linux/drivers/pci/pci.c (revision 2277ab4a1df50e05bc732fe9488d4e902bb8399a)
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/module.h>
16 #include <linux/spinlock.h>
17 #include <linux/string.h>
18 #include <linux/log2.h>
19 #include <linux/pci-aspm.h>
20 #include <linux/pm_wakeup.h>
21 #include <linux/interrupt.h>
22 #include <asm/dma.h>	/* isa_dma_bridge_buggy */
23 #include <linux/device.h>
24 #include <asm/setup.h>
25 #include "pci.h"
26 
27 const char *pci_power_names[] = {
28 	"error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
29 };
30 EXPORT_SYMBOL_GPL(pci_power_names);
31 
32 unsigned int pci_pm_d3_delay = PCI_PM_D3_WAIT;
33 
34 #ifdef CONFIG_PCI_DOMAINS
35 int pci_domains_supported = 1;
36 #endif
37 
38 #define DEFAULT_CARDBUS_IO_SIZE		(256)
39 #define DEFAULT_CARDBUS_MEM_SIZE	(64*1024*1024)
40 /* pci=cbmemsize=nnM,cbiosize=nn can override this */
41 unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
42 unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
43 
44 /**
45  * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
46  * @bus: pointer to PCI bus structure to search
47  *
48  * Given a PCI bus, returns the highest PCI bus number present in the set
49  * including the given PCI bus and its list of child PCI buses.
50  */
51 unsigned char pci_bus_max_busnr(struct pci_bus* bus)
52 {
53 	struct list_head *tmp;
54 	unsigned char max, n;
55 
56 	max = bus->subordinate;
57 	list_for_each(tmp, &bus->children) {
58 		n = pci_bus_max_busnr(pci_bus_b(tmp));
59 		if(n > max)
60 			max = n;
61 	}
62 	return max;
63 }
64 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
65 
66 #ifdef CONFIG_HAS_IOMEM
67 void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
68 {
69 	/*
70 	 * Make sure the BAR is actually a memory resource, not an IO resource
71 	 */
72 	if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
73 		WARN_ON(1);
74 		return NULL;
75 	}
76 	return ioremap_nocache(pci_resource_start(pdev, bar),
77 				     pci_resource_len(pdev, bar));
78 }
79 EXPORT_SYMBOL_GPL(pci_ioremap_bar);
80 #endif
81 
82 #if 0
83 /**
84  * pci_max_busnr - returns maximum PCI bus number
85  *
86  * Returns the highest PCI bus number present in the system global list of
87  * PCI buses.
88  */
89 unsigned char __devinit
90 pci_max_busnr(void)
91 {
92 	struct pci_bus *bus = NULL;
93 	unsigned char max, n;
94 
95 	max = 0;
96 	while ((bus = pci_find_next_bus(bus)) != NULL) {
97 		n = pci_bus_max_busnr(bus);
98 		if(n > max)
99 			max = n;
100 	}
101 	return max;
102 }
103 
104 #endif  /*  0  */
105 
106 #define PCI_FIND_CAP_TTL	48
107 
108 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
109 				   u8 pos, int cap, int *ttl)
110 {
111 	u8 id;
112 
113 	while ((*ttl)--) {
114 		pci_bus_read_config_byte(bus, devfn, pos, &pos);
115 		if (pos < 0x40)
116 			break;
117 		pos &= ~3;
118 		pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
119 					 &id);
120 		if (id == 0xff)
121 			break;
122 		if (id == cap)
123 			return pos;
124 		pos += PCI_CAP_LIST_NEXT;
125 	}
126 	return 0;
127 }
128 
129 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
130 			       u8 pos, int cap)
131 {
132 	int ttl = PCI_FIND_CAP_TTL;
133 
134 	return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
135 }
136 
137 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
138 {
139 	return __pci_find_next_cap(dev->bus, dev->devfn,
140 				   pos + PCI_CAP_LIST_NEXT, cap);
141 }
142 EXPORT_SYMBOL_GPL(pci_find_next_capability);
143 
144 static int __pci_bus_find_cap_start(struct pci_bus *bus,
145 				    unsigned int devfn, u8 hdr_type)
146 {
147 	u16 status;
148 
149 	pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
150 	if (!(status & PCI_STATUS_CAP_LIST))
151 		return 0;
152 
153 	switch (hdr_type) {
154 	case PCI_HEADER_TYPE_NORMAL:
155 	case PCI_HEADER_TYPE_BRIDGE:
156 		return PCI_CAPABILITY_LIST;
157 	case PCI_HEADER_TYPE_CARDBUS:
158 		return PCI_CB_CAPABILITY_LIST;
159 	default:
160 		return 0;
161 	}
162 
163 	return 0;
164 }
165 
166 /**
167  * pci_find_capability - query for devices' capabilities
168  * @dev: PCI device to query
169  * @cap: capability code
170  *
171  * Tell if a device supports a given PCI capability.
172  * Returns the address of the requested capability structure within the
173  * device's PCI configuration space or 0 in case the device does not
174  * support it.  Possible values for @cap:
175  *
176  *  %PCI_CAP_ID_PM           Power Management
177  *  %PCI_CAP_ID_AGP          Accelerated Graphics Port
178  *  %PCI_CAP_ID_VPD          Vital Product Data
179  *  %PCI_CAP_ID_SLOTID       Slot Identification
180  *  %PCI_CAP_ID_MSI          Message Signalled Interrupts
181  *  %PCI_CAP_ID_CHSWP        CompactPCI HotSwap
182  *  %PCI_CAP_ID_PCIX         PCI-X
183  *  %PCI_CAP_ID_EXP          PCI Express
184  */
185 int pci_find_capability(struct pci_dev *dev, int cap)
186 {
187 	int pos;
188 
189 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
190 	if (pos)
191 		pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
192 
193 	return pos;
194 }
195 
196 /**
197  * pci_bus_find_capability - query for devices' capabilities
198  * @bus:   the PCI bus to query
199  * @devfn: PCI device to query
200  * @cap:   capability code
201  *
202  * Like pci_find_capability() but works for pci devices that do not have a
203  * pci_dev structure set up yet.
204  *
205  * Returns the address of the requested capability structure within the
206  * device's PCI configuration space or 0 in case the device does not
207  * support it.
208  */
209 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
210 {
211 	int pos;
212 	u8 hdr_type;
213 
214 	pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
215 
216 	pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
217 	if (pos)
218 		pos = __pci_find_next_cap(bus, devfn, pos, cap);
219 
220 	return pos;
221 }
222 
223 /**
224  * pci_find_ext_capability - Find an extended capability
225  * @dev: PCI device to query
226  * @cap: capability code
227  *
228  * Returns the address of the requested extended capability structure
229  * within the device's PCI configuration space or 0 if the device does
230  * not support it.  Possible values for @cap:
231  *
232  *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
233  *  %PCI_EXT_CAP_ID_VC		Virtual Channel
234  *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
235  *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
236  */
237 int pci_find_ext_capability(struct pci_dev *dev, int cap)
238 {
239 	u32 header;
240 	int ttl;
241 	int pos = PCI_CFG_SPACE_SIZE;
242 
243 	/* minimum 8 bytes per capability */
244 	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
245 
246 	if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
247 		return 0;
248 
249 	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
250 		return 0;
251 
252 	/*
253 	 * If we have no capabilities, this is indicated by cap ID,
254 	 * cap version and next pointer all being 0.
255 	 */
256 	if (header == 0)
257 		return 0;
258 
259 	while (ttl-- > 0) {
260 		if (PCI_EXT_CAP_ID(header) == cap)
261 			return pos;
262 
263 		pos = PCI_EXT_CAP_NEXT(header);
264 		if (pos < PCI_CFG_SPACE_SIZE)
265 			break;
266 
267 		if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
268 			break;
269 	}
270 
271 	return 0;
272 }
273 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
274 
275 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
276 {
277 	int rc, ttl = PCI_FIND_CAP_TTL;
278 	u8 cap, mask;
279 
280 	if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
281 		mask = HT_3BIT_CAP_MASK;
282 	else
283 		mask = HT_5BIT_CAP_MASK;
284 
285 	pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
286 				      PCI_CAP_ID_HT, &ttl);
287 	while (pos) {
288 		rc = pci_read_config_byte(dev, pos + 3, &cap);
289 		if (rc != PCIBIOS_SUCCESSFUL)
290 			return 0;
291 
292 		if ((cap & mask) == ht_cap)
293 			return pos;
294 
295 		pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
296 					      pos + PCI_CAP_LIST_NEXT,
297 					      PCI_CAP_ID_HT, &ttl);
298 	}
299 
300 	return 0;
301 }
302 /**
303  * pci_find_next_ht_capability - query a device's Hypertransport capabilities
304  * @dev: PCI device to query
305  * @pos: Position from which to continue searching
306  * @ht_cap: Hypertransport capability code
307  *
308  * To be used in conjunction with pci_find_ht_capability() to search for
309  * all capabilities matching @ht_cap. @pos should always be a value returned
310  * from pci_find_ht_capability().
311  *
312  * NB. To be 100% safe against broken PCI devices, the caller should take
313  * steps to avoid an infinite loop.
314  */
315 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
316 {
317 	return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
318 }
319 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
320 
321 /**
322  * pci_find_ht_capability - query a device's Hypertransport capabilities
323  * @dev: PCI device to query
324  * @ht_cap: Hypertransport capability code
325  *
326  * Tell if a device supports a given Hypertransport capability.
327  * Returns an address within the device's PCI configuration space
328  * or 0 in case the device does not support the request capability.
329  * The address points to the PCI capability, of type PCI_CAP_ID_HT,
330  * which has a Hypertransport capability matching @ht_cap.
331  */
332 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
333 {
334 	int pos;
335 
336 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
337 	if (pos)
338 		pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
339 
340 	return pos;
341 }
342 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
343 
344 /**
345  * pci_find_parent_resource - return resource region of parent bus of given region
346  * @dev: PCI device structure contains resources to be searched
347  * @res: child resource record for which parent is sought
348  *
349  *  For given resource region of given device, return the resource
350  *  region of parent bus the given region is contained in or where
351  *  it should be allocated from.
352  */
353 struct resource *
354 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
355 {
356 	const struct pci_bus *bus = dev->bus;
357 	int i;
358 	struct resource *best = NULL;
359 
360 	for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
361 		struct resource *r = bus->resource[i];
362 		if (!r)
363 			continue;
364 		if (res->start && !(res->start >= r->start && res->end <= r->end))
365 			continue;	/* Not contained */
366 		if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
367 			continue;	/* Wrong type */
368 		if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
369 			return r;	/* Exact match */
370 		if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
371 			best = r;	/* Approximating prefetchable by non-prefetchable */
372 	}
373 	return best;
374 }
375 
376 /**
377  * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
378  * @dev: PCI device to have its BARs restored
379  *
380  * Restore the BAR values for a given device, so as to make it
381  * accessible by its driver.
382  */
383 static void
384 pci_restore_bars(struct pci_dev *dev)
385 {
386 	int i;
387 
388 	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
389 		pci_update_resource(dev, i);
390 }
391 
392 static struct pci_platform_pm_ops *pci_platform_pm;
393 
394 int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
395 {
396 	if (!ops->is_manageable || !ops->set_state || !ops->choose_state
397 	    || !ops->sleep_wake || !ops->can_wakeup)
398 		return -EINVAL;
399 	pci_platform_pm = ops;
400 	return 0;
401 }
402 
403 static inline bool platform_pci_power_manageable(struct pci_dev *dev)
404 {
405 	return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
406 }
407 
408 static inline int platform_pci_set_power_state(struct pci_dev *dev,
409                                                 pci_power_t t)
410 {
411 	return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
412 }
413 
414 static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
415 {
416 	return pci_platform_pm ?
417 			pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
418 }
419 
420 static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
421 {
422 	return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
423 }
424 
425 static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
426 {
427 	return pci_platform_pm ?
428 			pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
429 }
430 
431 /**
432  * pci_raw_set_power_state - Use PCI PM registers to set the power state of
433  *                           given PCI device
434  * @dev: PCI device to handle.
435  * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
436  *
437  * RETURN VALUE:
438  * -EINVAL if the requested state is invalid.
439  * -EIO if device does not support PCI PM or its PM capabilities register has a
440  * wrong version, or device doesn't support the requested state.
441  * 0 if device already is in the requested state.
442  * 0 if device's power state has been successfully changed.
443  */
444 static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
445 {
446 	u16 pmcsr;
447 	bool need_restore = false;
448 
449 	/* Check if we're already there */
450 	if (dev->current_state == state)
451 		return 0;
452 
453 	if (!dev->pm_cap)
454 		return -EIO;
455 
456 	if (state < PCI_D0 || state > PCI_D3hot)
457 		return -EINVAL;
458 
459 	/* Validate current state:
460 	 * Can enter D0 from any state, but if we can only go deeper
461 	 * to sleep if we're already in a low power state
462 	 */
463 	if (state != PCI_D0 && dev->current_state <= PCI_D3cold
464 	    && dev->current_state > state) {
465 		dev_err(&dev->dev, "invalid power transition "
466 			"(from state %d to %d)\n", dev->current_state, state);
467 		return -EINVAL;
468 	}
469 
470 	/* check if this device supports the desired state */
471 	if ((state == PCI_D1 && !dev->d1_support)
472 	   || (state == PCI_D2 && !dev->d2_support))
473 		return -EIO;
474 
475 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
476 
477 	/* If we're (effectively) in D3, force entire word to 0.
478 	 * This doesn't affect PME_Status, disables PME_En, and
479 	 * sets PowerState to 0.
480 	 */
481 	switch (dev->current_state) {
482 	case PCI_D0:
483 	case PCI_D1:
484 	case PCI_D2:
485 		pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
486 		pmcsr |= state;
487 		break;
488 	case PCI_D3hot:
489 	case PCI_D3cold:
490 	case PCI_UNKNOWN: /* Boot-up */
491 		if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
492 		 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
493 			need_restore = true;
494 		/* Fall-through: force to D0 */
495 	default:
496 		pmcsr = 0;
497 		break;
498 	}
499 
500 	/* enter specified state */
501 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
502 
503 	/* Mandatory power management transition delays */
504 	/* see PCI PM 1.1 5.6.1 table 18 */
505 	if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
506 		msleep(pci_pm_d3_delay);
507 	else if (state == PCI_D2 || dev->current_state == PCI_D2)
508 		udelay(PCI_PM_D2_DELAY);
509 
510 	dev->current_state = state;
511 
512 	/* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
513 	 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
514 	 * from D3hot to D0 _may_ perform an internal reset, thereby
515 	 * going to "D0 Uninitialized" rather than "D0 Initialized".
516 	 * For example, at least some versions of the 3c905B and the
517 	 * 3c556B exhibit this behaviour.
518 	 *
519 	 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
520 	 * devices in a D3hot state at boot.  Consequently, we need to
521 	 * restore at least the BARs so that the device will be
522 	 * accessible to its driver.
523 	 */
524 	if (need_restore)
525 		pci_restore_bars(dev);
526 
527 	if (dev->bus->self)
528 		pcie_aspm_pm_state_change(dev->bus->self);
529 
530 	return 0;
531 }
532 
533 /**
534  * pci_update_current_state - Read PCI power state of given device from its
535  *                            PCI PM registers and cache it
536  * @dev: PCI device to handle.
537  * @state: State to cache in case the device doesn't have the PM capability
538  */
539 void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
540 {
541 	if (dev->pm_cap) {
542 		u16 pmcsr;
543 
544 		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
545 		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
546 	} else {
547 		dev->current_state = state;
548 	}
549 }
550 
551 /**
552  * pci_platform_power_transition - Use platform to change device power state
553  * @dev: PCI device to handle.
554  * @state: State to put the device into.
555  */
556 static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
557 {
558 	int error;
559 
560 	if (platform_pci_power_manageable(dev)) {
561 		error = platform_pci_set_power_state(dev, state);
562 		if (!error)
563 			pci_update_current_state(dev, state);
564 	} else {
565 		error = -ENODEV;
566 		/* Fall back to PCI_D0 if native PM is not supported */
567 		if (!dev->pm_cap)
568 			dev->current_state = PCI_D0;
569 	}
570 
571 	return error;
572 }
573 
574 /**
575  * __pci_start_power_transition - Start power transition of a PCI device
576  * @dev: PCI device to handle.
577  * @state: State to put the device into.
578  */
579 static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
580 {
581 	if (state == PCI_D0)
582 		pci_platform_power_transition(dev, PCI_D0);
583 }
584 
585 /**
586  * __pci_complete_power_transition - Complete power transition of a PCI device
587  * @dev: PCI device to handle.
588  * @state: State to put the device into.
589  *
590  * This function should not be called directly by device drivers.
591  */
592 int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
593 {
594 	return state > PCI_D0 ?
595 			pci_platform_power_transition(dev, state) : -EINVAL;
596 }
597 EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
598 
599 /**
600  * pci_set_power_state - Set the power state of a PCI device
601  * @dev: PCI device to handle.
602  * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
603  *
604  * Transition a device to a new power state, using the platform firmware and/or
605  * the device's PCI PM registers.
606  *
607  * RETURN VALUE:
608  * -EINVAL if the requested state is invalid.
609  * -EIO if device does not support PCI PM or its PM capabilities register has a
610  * wrong version, or device doesn't support the requested state.
611  * 0 if device already is in the requested state.
612  * 0 if device's power state has been successfully changed.
613  */
614 int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
615 {
616 	int error;
617 
618 	/* bound the state we're entering */
619 	if (state > PCI_D3hot)
620 		state = PCI_D3hot;
621 	else if (state < PCI_D0)
622 		state = PCI_D0;
623 	else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
624 		/*
625 		 * If the device or the parent bridge do not support PCI PM,
626 		 * ignore the request if we're doing anything other than putting
627 		 * it into D0 (which would only happen on boot).
628 		 */
629 		return 0;
630 
631 	/* Check if we're already there */
632 	if (dev->current_state == state)
633 		return 0;
634 
635 	__pci_start_power_transition(dev, state);
636 
637 	/* This device is quirked not to be put into D3, so
638 	   don't put it in D3 */
639 	if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
640 		return 0;
641 
642 	error = pci_raw_set_power_state(dev, state);
643 
644 	if (!__pci_complete_power_transition(dev, state))
645 		error = 0;
646 
647 	return error;
648 }
649 
650 /**
651  * pci_choose_state - Choose the power state of a PCI device
652  * @dev: PCI device to be suspended
653  * @state: target sleep state for the whole system. This is the value
654  *	that is passed to suspend() function.
655  *
656  * Returns PCI power state suitable for given device and given system
657  * message.
658  */
659 
660 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
661 {
662 	pci_power_t ret;
663 
664 	if (!pci_find_capability(dev, PCI_CAP_ID_PM))
665 		return PCI_D0;
666 
667 	ret = platform_pci_choose_state(dev);
668 	if (ret != PCI_POWER_ERROR)
669 		return ret;
670 
671 	switch (state.event) {
672 	case PM_EVENT_ON:
673 		return PCI_D0;
674 	case PM_EVENT_FREEZE:
675 	case PM_EVENT_PRETHAW:
676 		/* REVISIT both freeze and pre-thaw "should" use D0 */
677 	case PM_EVENT_SUSPEND:
678 	case PM_EVENT_HIBERNATE:
679 		return PCI_D3hot;
680 	default:
681 		dev_info(&dev->dev, "unrecognized suspend event %d\n",
682 			 state.event);
683 		BUG();
684 	}
685 	return PCI_D0;
686 }
687 
688 EXPORT_SYMBOL(pci_choose_state);
689 
690 #define PCI_EXP_SAVE_REGS	7
691 
692 #define pcie_cap_has_devctl(type, flags)	1
693 #define pcie_cap_has_lnkctl(type, flags)		\
694 		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
695 		 (type == PCI_EXP_TYPE_ROOT_PORT ||	\
696 		  type == PCI_EXP_TYPE_ENDPOINT ||	\
697 		  type == PCI_EXP_TYPE_LEG_END))
698 #define pcie_cap_has_sltctl(type, flags)		\
699 		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
700 		 ((type == PCI_EXP_TYPE_ROOT_PORT) ||	\
701 		  (type == PCI_EXP_TYPE_DOWNSTREAM &&	\
702 		   (flags & PCI_EXP_FLAGS_SLOT))))
703 #define pcie_cap_has_rtctl(type, flags)			\
704 		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
705 		 (type == PCI_EXP_TYPE_ROOT_PORT ||	\
706 		  type == PCI_EXP_TYPE_RC_EC))
707 #define pcie_cap_has_devctl2(type, flags)		\
708 		((flags & PCI_EXP_FLAGS_VERS) > 1)
709 #define pcie_cap_has_lnkctl2(type, flags)		\
710 		((flags & PCI_EXP_FLAGS_VERS) > 1)
711 #define pcie_cap_has_sltctl2(type, flags)		\
712 		((flags & PCI_EXP_FLAGS_VERS) > 1)
713 
714 static int pci_save_pcie_state(struct pci_dev *dev)
715 {
716 	int pos, i = 0;
717 	struct pci_cap_saved_state *save_state;
718 	u16 *cap;
719 	u16 flags;
720 
721 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
722 	if (pos <= 0)
723 		return 0;
724 
725 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
726 	if (!save_state) {
727 		dev_err(&dev->dev, "buffer not found in %s\n", __func__);
728 		return -ENOMEM;
729 	}
730 	cap = (u16 *)&save_state->data[0];
731 
732 	pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
733 
734 	if (pcie_cap_has_devctl(dev->pcie_type, flags))
735 		pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
736 	if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
737 		pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
738 	if (pcie_cap_has_sltctl(dev->pcie_type, flags))
739 		pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
740 	if (pcie_cap_has_rtctl(dev->pcie_type, flags))
741 		pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
742 	if (pcie_cap_has_devctl2(dev->pcie_type, flags))
743 		pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &cap[i++]);
744 	if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
745 		pci_read_config_word(dev, pos + PCI_EXP_LNKCTL2, &cap[i++]);
746 	if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
747 		pci_read_config_word(dev, pos + PCI_EXP_SLTCTL2, &cap[i++]);
748 
749 	return 0;
750 }
751 
752 static void pci_restore_pcie_state(struct pci_dev *dev)
753 {
754 	int i = 0, pos;
755 	struct pci_cap_saved_state *save_state;
756 	u16 *cap;
757 	u16 flags;
758 
759 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
760 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
761 	if (!save_state || pos <= 0)
762 		return;
763 	cap = (u16 *)&save_state->data[0];
764 
765 	pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
766 
767 	if (pcie_cap_has_devctl(dev->pcie_type, flags))
768 		pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
769 	if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
770 		pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
771 	if (pcie_cap_has_sltctl(dev->pcie_type, flags))
772 		pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
773 	if (pcie_cap_has_rtctl(dev->pcie_type, flags))
774 		pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
775 	if (pcie_cap_has_devctl2(dev->pcie_type, flags))
776 		pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, cap[i++]);
777 	if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
778 		pci_write_config_word(dev, pos + PCI_EXP_LNKCTL2, cap[i++]);
779 	if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
780 		pci_write_config_word(dev, pos + PCI_EXP_SLTCTL2, cap[i++]);
781 }
782 
783 
784 static int pci_save_pcix_state(struct pci_dev *dev)
785 {
786 	int pos;
787 	struct pci_cap_saved_state *save_state;
788 
789 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
790 	if (pos <= 0)
791 		return 0;
792 
793 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
794 	if (!save_state) {
795 		dev_err(&dev->dev, "buffer not found in %s\n", __func__);
796 		return -ENOMEM;
797 	}
798 
799 	pci_read_config_word(dev, pos + PCI_X_CMD, (u16 *)save_state->data);
800 
801 	return 0;
802 }
803 
804 static void pci_restore_pcix_state(struct pci_dev *dev)
805 {
806 	int i = 0, pos;
807 	struct pci_cap_saved_state *save_state;
808 	u16 *cap;
809 
810 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
811 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
812 	if (!save_state || pos <= 0)
813 		return;
814 	cap = (u16 *)&save_state->data[0];
815 
816 	pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
817 }
818 
819 
820 /**
821  * pci_save_state - save the PCI configuration space of a device before suspending
822  * @dev: - PCI device that we're dealing with
823  */
824 int
825 pci_save_state(struct pci_dev *dev)
826 {
827 	int i;
828 	/* XXX: 100% dword access ok here? */
829 	for (i = 0; i < 16; i++)
830 		pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
831 	dev->state_saved = true;
832 	if ((i = pci_save_pcie_state(dev)) != 0)
833 		return i;
834 	if ((i = pci_save_pcix_state(dev)) != 0)
835 		return i;
836 	return 0;
837 }
838 
839 /**
840  * pci_restore_state - Restore the saved state of a PCI device
841  * @dev: - PCI device that we're dealing with
842  */
843 int
844 pci_restore_state(struct pci_dev *dev)
845 {
846 	int i;
847 	u32 val;
848 
849 	/* PCI Express register must be restored first */
850 	pci_restore_pcie_state(dev);
851 
852 	/*
853 	 * The Base Address register should be programmed before the command
854 	 * register(s)
855 	 */
856 	for (i = 15; i >= 0; i--) {
857 		pci_read_config_dword(dev, i * 4, &val);
858 		if (val != dev->saved_config_space[i]) {
859 			dev_printk(KERN_DEBUG, &dev->dev, "restoring config "
860 				"space at offset %#x (was %#x, writing %#x)\n",
861 				i, val, (int)dev->saved_config_space[i]);
862 			pci_write_config_dword(dev,i * 4,
863 				dev->saved_config_space[i]);
864 		}
865 	}
866 	pci_restore_pcix_state(dev);
867 	pci_restore_msi_state(dev);
868 	pci_restore_iov_state(dev);
869 
870 	return 0;
871 }
872 
873 static int do_pci_enable_device(struct pci_dev *dev, int bars)
874 {
875 	int err;
876 
877 	err = pci_set_power_state(dev, PCI_D0);
878 	if (err < 0 && err != -EIO)
879 		return err;
880 	err = pcibios_enable_device(dev, bars);
881 	if (err < 0)
882 		return err;
883 	pci_fixup_device(pci_fixup_enable, dev);
884 
885 	return 0;
886 }
887 
888 /**
889  * pci_reenable_device - Resume abandoned device
890  * @dev: PCI device to be resumed
891  *
892  *  Note this function is a backend of pci_default_resume and is not supposed
893  *  to be called by normal code, write proper resume handler and use it instead.
894  */
895 int pci_reenable_device(struct pci_dev *dev)
896 {
897 	if (pci_is_enabled(dev))
898 		return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
899 	return 0;
900 }
901 
902 static int __pci_enable_device_flags(struct pci_dev *dev,
903 				     resource_size_t flags)
904 {
905 	int err;
906 	int i, bars = 0;
907 
908 	if (atomic_add_return(1, &dev->enable_cnt) > 1)
909 		return 0;		/* already enabled */
910 
911 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
912 		if (dev->resource[i].flags & flags)
913 			bars |= (1 << i);
914 
915 	err = do_pci_enable_device(dev, bars);
916 	if (err < 0)
917 		atomic_dec(&dev->enable_cnt);
918 	return err;
919 }
920 
921 /**
922  * pci_enable_device_io - Initialize a device for use with IO space
923  * @dev: PCI device to be initialized
924  *
925  *  Initialize device before it's used by a driver. Ask low-level code
926  *  to enable I/O resources. Wake up the device if it was suspended.
927  *  Beware, this function can fail.
928  */
929 int pci_enable_device_io(struct pci_dev *dev)
930 {
931 	return __pci_enable_device_flags(dev, IORESOURCE_IO);
932 }
933 
934 /**
935  * pci_enable_device_mem - Initialize a device for use with Memory space
936  * @dev: PCI device to be initialized
937  *
938  *  Initialize device before it's used by a driver. Ask low-level code
939  *  to enable Memory resources. Wake up the device if it was suspended.
940  *  Beware, this function can fail.
941  */
942 int pci_enable_device_mem(struct pci_dev *dev)
943 {
944 	return __pci_enable_device_flags(dev, IORESOURCE_MEM);
945 }
946 
947 /**
948  * pci_enable_device - Initialize device before it's used by a driver.
949  * @dev: PCI device to be initialized
950  *
951  *  Initialize device before it's used by a driver. Ask low-level code
952  *  to enable I/O and memory. Wake up the device if it was suspended.
953  *  Beware, this function can fail.
954  *
955  *  Note we don't actually enable the device many times if we call
956  *  this function repeatedly (we just increment the count).
957  */
958 int pci_enable_device(struct pci_dev *dev)
959 {
960 	return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
961 }
962 
963 /*
964  * Managed PCI resources.  This manages device on/off, intx/msi/msix
965  * on/off and BAR regions.  pci_dev itself records msi/msix status, so
966  * there's no need to track it separately.  pci_devres is initialized
967  * when a device is enabled using managed PCI device enable interface.
968  */
969 struct pci_devres {
970 	unsigned int enabled:1;
971 	unsigned int pinned:1;
972 	unsigned int orig_intx:1;
973 	unsigned int restore_intx:1;
974 	u32 region_mask;
975 };
976 
977 static void pcim_release(struct device *gendev, void *res)
978 {
979 	struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
980 	struct pci_devres *this = res;
981 	int i;
982 
983 	if (dev->msi_enabled)
984 		pci_disable_msi(dev);
985 	if (dev->msix_enabled)
986 		pci_disable_msix(dev);
987 
988 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
989 		if (this->region_mask & (1 << i))
990 			pci_release_region(dev, i);
991 
992 	if (this->restore_intx)
993 		pci_intx(dev, this->orig_intx);
994 
995 	if (this->enabled && !this->pinned)
996 		pci_disable_device(dev);
997 }
998 
999 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
1000 {
1001 	struct pci_devres *dr, *new_dr;
1002 
1003 	dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1004 	if (dr)
1005 		return dr;
1006 
1007 	new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1008 	if (!new_dr)
1009 		return NULL;
1010 	return devres_get(&pdev->dev, new_dr, NULL, NULL);
1011 }
1012 
1013 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
1014 {
1015 	if (pci_is_managed(pdev))
1016 		return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1017 	return NULL;
1018 }
1019 
1020 /**
1021  * pcim_enable_device - Managed pci_enable_device()
1022  * @pdev: PCI device to be initialized
1023  *
1024  * Managed pci_enable_device().
1025  */
1026 int pcim_enable_device(struct pci_dev *pdev)
1027 {
1028 	struct pci_devres *dr;
1029 	int rc;
1030 
1031 	dr = get_pci_dr(pdev);
1032 	if (unlikely(!dr))
1033 		return -ENOMEM;
1034 	if (dr->enabled)
1035 		return 0;
1036 
1037 	rc = pci_enable_device(pdev);
1038 	if (!rc) {
1039 		pdev->is_managed = 1;
1040 		dr->enabled = 1;
1041 	}
1042 	return rc;
1043 }
1044 
1045 /**
1046  * pcim_pin_device - Pin managed PCI device
1047  * @pdev: PCI device to pin
1048  *
1049  * Pin managed PCI device @pdev.  Pinned device won't be disabled on
1050  * driver detach.  @pdev must have been enabled with
1051  * pcim_enable_device().
1052  */
1053 void pcim_pin_device(struct pci_dev *pdev)
1054 {
1055 	struct pci_devres *dr;
1056 
1057 	dr = find_pci_dr(pdev);
1058 	WARN_ON(!dr || !dr->enabled);
1059 	if (dr)
1060 		dr->pinned = 1;
1061 }
1062 
1063 /**
1064  * pcibios_disable_device - disable arch specific PCI resources for device dev
1065  * @dev: the PCI device to disable
1066  *
1067  * Disables architecture specific PCI resources for the device. This
1068  * is the default implementation. Architecture implementations can
1069  * override this.
1070  */
1071 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
1072 
1073 static void do_pci_disable_device(struct pci_dev *dev)
1074 {
1075 	u16 pci_command;
1076 
1077 	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1078 	if (pci_command & PCI_COMMAND_MASTER) {
1079 		pci_command &= ~PCI_COMMAND_MASTER;
1080 		pci_write_config_word(dev, PCI_COMMAND, pci_command);
1081 	}
1082 
1083 	pcibios_disable_device(dev);
1084 }
1085 
1086 /**
1087  * pci_disable_enabled_device - Disable device without updating enable_cnt
1088  * @dev: PCI device to disable
1089  *
1090  * NOTE: This function is a backend of PCI power management routines and is
1091  * not supposed to be called drivers.
1092  */
1093 void pci_disable_enabled_device(struct pci_dev *dev)
1094 {
1095 	if (pci_is_enabled(dev))
1096 		do_pci_disable_device(dev);
1097 }
1098 
1099 /**
1100  * pci_disable_device - Disable PCI device after use
1101  * @dev: PCI device to be disabled
1102  *
1103  * Signal to the system that the PCI device is not in use by the system
1104  * anymore.  This only involves disabling PCI bus-mastering, if active.
1105  *
1106  * Note we don't actually disable the device until all callers of
1107  * pci_device_enable() have called pci_device_disable().
1108  */
1109 void
1110 pci_disable_device(struct pci_dev *dev)
1111 {
1112 	struct pci_devres *dr;
1113 
1114 	dr = find_pci_dr(dev);
1115 	if (dr)
1116 		dr->enabled = 0;
1117 
1118 	if (atomic_sub_return(1, &dev->enable_cnt) != 0)
1119 		return;
1120 
1121 	do_pci_disable_device(dev);
1122 
1123 	dev->is_busmaster = 0;
1124 }
1125 
1126 /**
1127  * pcibios_set_pcie_reset_state - set reset state for device dev
1128  * @dev: the PCI-E device reset
1129  * @state: Reset state to enter into
1130  *
1131  *
1132  * Sets the PCI-E reset state for the device. This is the default
1133  * implementation. Architecture implementations can override this.
1134  */
1135 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
1136 							enum pcie_reset_state state)
1137 {
1138 	return -EINVAL;
1139 }
1140 
1141 /**
1142  * pci_set_pcie_reset_state - set reset state for device dev
1143  * @dev: the PCI-E device reset
1144  * @state: Reset state to enter into
1145  *
1146  *
1147  * Sets the PCI reset state for the device.
1148  */
1149 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1150 {
1151 	return pcibios_set_pcie_reset_state(dev, state);
1152 }
1153 
1154 /**
1155  * pci_pme_capable - check the capability of PCI device to generate PME#
1156  * @dev: PCI device to handle.
1157  * @state: PCI state from which device will issue PME#.
1158  */
1159 bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1160 {
1161 	if (!dev->pm_cap)
1162 		return false;
1163 
1164 	return !!(dev->pme_support & (1 << state));
1165 }
1166 
1167 /**
1168  * pci_pme_active - enable or disable PCI device's PME# function
1169  * @dev: PCI device to handle.
1170  * @enable: 'true' to enable PME# generation; 'false' to disable it.
1171  *
1172  * The caller must verify that the device is capable of generating PME# before
1173  * calling this function with @enable equal to 'true'.
1174  */
1175 void pci_pme_active(struct pci_dev *dev, bool enable)
1176 {
1177 	u16 pmcsr;
1178 
1179 	if (!dev->pm_cap)
1180 		return;
1181 
1182 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1183 	/* Clear PME_Status by writing 1 to it and enable PME# */
1184 	pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1185 	if (!enable)
1186 		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1187 
1188 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1189 
1190 	dev_printk(KERN_INFO, &dev->dev, "PME# %s\n",
1191 			enable ? "enabled" : "disabled");
1192 }
1193 
1194 /**
1195  * pci_enable_wake - enable PCI device as wakeup event source
1196  * @dev: PCI device affected
1197  * @state: PCI state from which device will issue wakeup events
1198  * @enable: True to enable event generation; false to disable
1199  *
1200  * This enables the device as a wakeup event source, or disables it.
1201  * When such events involves platform-specific hooks, those hooks are
1202  * called automatically by this routine.
1203  *
1204  * Devices with legacy power management (no standard PCI PM capabilities)
1205  * always require such platform hooks.
1206  *
1207  * RETURN VALUE:
1208  * 0 is returned on success
1209  * -EINVAL is returned if device is not supposed to wake up the system
1210  * Error code depending on the platform is returned if both the platform and
1211  * the native mechanism fail to enable the generation of wake-up events
1212  */
1213 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool enable)
1214 {
1215 	int error = 0;
1216 	bool pme_done = false;
1217 
1218 	if (enable && !device_may_wakeup(&dev->dev))
1219 		return -EINVAL;
1220 
1221 	/*
1222 	 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1223 	 * Anderson we should be doing PME# wake enable followed by ACPI wake
1224 	 * enable.  To disable wake-up we call the platform first, for symmetry.
1225 	 */
1226 
1227 	if (!enable && platform_pci_can_wakeup(dev))
1228 		error = platform_pci_sleep_wake(dev, false);
1229 
1230 	if (!enable || pci_pme_capable(dev, state)) {
1231 		pci_pme_active(dev, enable);
1232 		pme_done = true;
1233 	}
1234 
1235 	if (enable && platform_pci_can_wakeup(dev))
1236 		error = platform_pci_sleep_wake(dev, true);
1237 
1238 	return pme_done ? 0 : error;
1239 }
1240 
1241 /**
1242  * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1243  * @dev: PCI device to prepare
1244  * @enable: True to enable wake-up event generation; false to disable
1245  *
1246  * Many drivers want the device to wake up the system from D3_hot or D3_cold
1247  * and this function allows them to set that up cleanly - pci_enable_wake()
1248  * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1249  * ordering constraints.
1250  *
1251  * This function only returns error code if the device is not capable of
1252  * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1253  * enable wake-up power for it.
1254  */
1255 int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1256 {
1257 	return pci_pme_capable(dev, PCI_D3cold) ?
1258 			pci_enable_wake(dev, PCI_D3cold, enable) :
1259 			pci_enable_wake(dev, PCI_D3hot, enable);
1260 }
1261 
1262 /**
1263  * pci_target_state - find an appropriate low power state for a given PCI dev
1264  * @dev: PCI device
1265  *
1266  * Use underlying platform code to find a supported low power state for @dev.
1267  * If the platform can't manage @dev, return the deepest state from which it
1268  * can generate wake events, based on any available PME info.
1269  */
1270 pci_power_t pci_target_state(struct pci_dev *dev)
1271 {
1272 	pci_power_t target_state = PCI_D3hot;
1273 
1274 	if (platform_pci_power_manageable(dev)) {
1275 		/*
1276 		 * Call the platform to choose the target state of the device
1277 		 * and enable wake-up from this state if supported.
1278 		 */
1279 		pci_power_t state = platform_pci_choose_state(dev);
1280 
1281 		switch (state) {
1282 		case PCI_POWER_ERROR:
1283 		case PCI_UNKNOWN:
1284 			break;
1285 		case PCI_D1:
1286 		case PCI_D2:
1287 			if (pci_no_d1d2(dev))
1288 				break;
1289 		default:
1290 			target_state = state;
1291 		}
1292 	} else if (!dev->pm_cap) {
1293 		target_state = PCI_D0;
1294 	} else if (device_may_wakeup(&dev->dev)) {
1295 		/*
1296 		 * Find the deepest state from which the device can generate
1297 		 * wake-up events, make it the target state and enable device
1298 		 * to generate PME#.
1299 		 */
1300 		if (dev->pme_support) {
1301 			while (target_state
1302 			      && !(dev->pme_support & (1 << target_state)))
1303 				target_state--;
1304 		}
1305 	}
1306 
1307 	return target_state;
1308 }
1309 
1310 /**
1311  * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1312  * @dev: Device to handle.
1313  *
1314  * Choose the power state appropriate for the device depending on whether
1315  * it can wake up the system and/or is power manageable by the platform
1316  * (PCI_D3hot is the default) and put the device into that state.
1317  */
1318 int pci_prepare_to_sleep(struct pci_dev *dev)
1319 {
1320 	pci_power_t target_state = pci_target_state(dev);
1321 	int error;
1322 
1323 	if (target_state == PCI_POWER_ERROR)
1324 		return -EIO;
1325 
1326 	pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
1327 
1328 	error = pci_set_power_state(dev, target_state);
1329 
1330 	if (error)
1331 		pci_enable_wake(dev, target_state, false);
1332 
1333 	return error;
1334 }
1335 
1336 /**
1337  * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1338  * @dev: Device to handle.
1339  *
1340  * Disable device's sytem wake-up capability and put it into D0.
1341  */
1342 int pci_back_from_sleep(struct pci_dev *dev)
1343 {
1344 	pci_enable_wake(dev, PCI_D0, false);
1345 	return pci_set_power_state(dev, PCI_D0);
1346 }
1347 
1348 /**
1349  * pci_pm_init - Initialize PM functions of given PCI device
1350  * @dev: PCI device to handle.
1351  */
1352 void pci_pm_init(struct pci_dev *dev)
1353 {
1354 	int pm;
1355 	u16 pmc;
1356 
1357 	dev->pm_cap = 0;
1358 
1359 	/* find PCI PM capability in list */
1360 	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
1361 	if (!pm)
1362 		return;
1363 	/* Check device's ability to generate PME# */
1364 	pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
1365 
1366 	if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
1367 		dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
1368 			pmc & PCI_PM_CAP_VER_MASK);
1369 		return;
1370 	}
1371 
1372 	dev->pm_cap = pm;
1373 
1374 	dev->d1_support = false;
1375 	dev->d2_support = false;
1376 	if (!pci_no_d1d2(dev)) {
1377 		if (pmc & PCI_PM_CAP_D1)
1378 			dev->d1_support = true;
1379 		if (pmc & PCI_PM_CAP_D2)
1380 			dev->d2_support = true;
1381 
1382 		if (dev->d1_support || dev->d2_support)
1383 			dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
1384 				   dev->d1_support ? " D1" : "",
1385 				   dev->d2_support ? " D2" : "");
1386 	}
1387 
1388 	pmc &= PCI_PM_CAP_PME_MASK;
1389 	if (pmc) {
1390 		dev_info(&dev->dev, "PME# supported from%s%s%s%s%s\n",
1391 			 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
1392 			 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
1393 			 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
1394 			 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
1395 			 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
1396 		dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
1397 		/*
1398 		 * Make device's PM flags reflect the wake-up capability, but
1399 		 * let the user space enable it to wake up the system as needed.
1400 		 */
1401 		device_set_wakeup_capable(&dev->dev, true);
1402 		device_set_wakeup_enable(&dev->dev, false);
1403 		/* Disable the PME# generation functionality */
1404 		pci_pme_active(dev, false);
1405 	} else {
1406 		dev->pme_support = 0;
1407 	}
1408 }
1409 
1410 /**
1411  * platform_pci_wakeup_init - init platform wakeup if present
1412  * @dev: PCI device
1413  *
1414  * Some devices don't have PCI PM caps but can still generate wakeup
1415  * events through platform methods (like ACPI events).  If @dev supports
1416  * platform wakeup events, set the device flag to indicate as much.  This
1417  * may be redundant if the device also supports PCI PM caps, but double
1418  * initialization should be safe in that case.
1419  */
1420 void platform_pci_wakeup_init(struct pci_dev *dev)
1421 {
1422 	if (!platform_pci_can_wakeup(dev))
1423 		return;
1424 
1425 	device_set_wakeup_capable(&dev->dev, true);
1426 	device_set_wakeup_enable(&dev->dev, false);
1427 	platform_pci_sleep_wake(dev, false);
1428 }
1429 
1430 /**
1431  * pci_add_save_buffer - allocate buffer for saving given capability registers
1432  * @dev: the PCI device
1433  * @cap: the capability to allocate the buffer for
1434  * @size: requested size of the buffer
1435  */
1436 static int pci_add_cap_save_buffer(
1437 	struct pci_dev *dev, char cap, unsigned int size)
1438 {
1439 	int pos;
1440 	struct pci_cap_saved_state *save_state;
1441 
1442 	pos = pci_find_capability(dev, cap);
1443 	if (pos <= 0)
1444 		return 0;
1445 
1446 	save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
1447 	if (!save_state)
1448 		return -ENOMEM;
1449 
1450 	save_state->cap_nr = cap;
1451 	pci_add_saved_cap(dev, save_state);
1452 
1453 	return 0;
1454 }
1455 
1456 /**
1457  * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
1458  * @dev: the PCI device
1459  */
1460 void pci_allocate_cap_save_buffers(struct pci_dev *dev)
1461 {
1462 	int error;
1463 
1464 	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
1465 					PCI_EXP_SAVE_REGS * sizeof(u16));
1466 	if (error)
1467 		dev_err(&dev->dev,
1468 			"unable to preallocate PCI Express save buffer\n");
1469 
1470 	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
1471 	if (error)
1472 		dev_err(&dev->dev,
1473 			"unable to preallocate PCI-X save buffer\n");
1474 }
1475 
1476 /**
1477  * pci_enable_ari - enable ARI forwarding if hardware support it
1478  * @dev: the PCI device
1479  */
1480 void pci_enable_ari(struct pci_dev *dev)
1481 {
1482 	int pos;
1483 	u32 cap;
1484 	u16 ctrl;
1485 	struct pci_dev *bridge;
1486 
1487 	if (!dev->is_pcie || dev->devfn)
1488 		return;
1489 
1490 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1491 	if (!pos)
1492 		return;
1493 
1494 	bridge = dev->bus->self;
1495 	if (!bridge || !bridge->is_pcie)
1496 		return;
1497 
1498 	pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
1499 	if (!pos)
1500 		return;
1501 
1502 	pci_read_config_dword(bridge, pos + PCI_EXP_DEVCAP2, &cap);
1503 	if (!(cap & PCI_EXP_DEVCAP2_ARI))
1504 		return;
1505 
1506 	pci_read_config_word(bridge, pos + PCI_EXP_DEVCTL2, &ctrl);
1507 	ctrl |= PCI_EXP_DEVCTL2_ARI;
1508 	pci_write_config_word(bridge, pos + PCI_EXP_DEVCTL2, ctrl);
1509 
1510 	bridge->ari_enabled = 1;
1511 }
1512 
1513 /**
1514  * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
1515  * @dev: the PCI device
1516  * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTD, 4=INTD)
1517  *
1518  * Perform INTx swizzling for a device behind one level of bridge.  This is
1519  * required by section 9.1 of the PCI-to-PCI bridge specification for devices
1520  * behind bridges on add-in cards.  For devices with ARI enabled, the slot
1521  * number is always 0 (see the Implementation Note in section 2.2.8.1 of
1522  * the PCI Express Base Specification, Revision 2.1)
1523  */
1524 u8 pci_swizzle_interrupt_pin(struct pci_dev *dev, u8 pin)
1525 {
1526 	int slot;
1527 
1528 	if (pci_ari_enabled(dev->bus))
1529 		slot = 0;
1530 	else
1531 		slot = PCI_SLOT(dev->devfn);
1532 
1533 	return (((pin - 1) + slot) % 4) + 1;
1534 }
1535 
1536 int
1537 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
1538 {
1539 	u8 pin;
1540 
1541 	pin = dev->pin;
1542 	if (!pin)
1543 		return -1;
1544 
1545 	while (!pci_is_root_bus(dev->bus)) {
1546 		pin = pci_swizzle_interrupt_pin(dev, pin);
1547 		dev = dev->bus->self;
1548 	}
1549 	*bridge = dev;
1550 	return pin;
1551 }
1552 
1553 /**
1554  * pci_common_swizzle - swizzle INTx all the way to root bridge
1555  * @dev: the PCI device
1556  * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
1557  *
1558  * Perform INTx swizzling for a device.  This traverses through all PCI-to-PCI
1559  * bridges all the way up to a PCI root bus.
1560  */
1561 u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
1562 {
1563 	u8 pin = *pinp;
1564 
1565 	while (!pci_is_root_bus(dev->bus)) {
1566 		pin = pci_swizzle_interrupt_pin(dev, pin);
1567 		dev = dev->bus->self;
1568 	}
1569 	*pinp = pin;
1570 	return PCI_SLOT(dev->devfn);
1571 }
1572 
1573 /**
1574  *	pci_release_region - Release a PCI bar
1575  *	@pdev: PCI device whose resources were previously reserved by pci_request_region
1576  *	@bar: BAR to release
1577  *
1578  *	Releases the PCI I/O and memory resources previously reserved by a
1579  *	successful call to pci_request_region.  Call this function only
1580  *	after all use of the PCI regions has ceased.
1581  */
1582 void pci_release_region(struct pci_dev *pdev, int bar)
1583 {
1584 	struct pci_devres *dr;
1585 
1586 	if (pci_resource_len(pdev, bar) == 0)
1587 		return;
1588 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1589 		release_region(pci_resource_start(pdev, bar),
1590 				pci_resource_len(pdev, bar));
1591 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1592 		release_mem_region(pci_resource_start(pdev, bar),
1593 				pci_resource_len(pdev, bar));
1594 
1595 	dr = find_pci_dr(pdev);
1596 	if (dr)
1597 		dr->region_mask &= ~(1 << bar);
1598 }
1599 
1600 /**
1601  *	__pci_request_region - Reserved PCI I/O and memory resource
1602  *	@pdev: PCI device whose resources are to be reserved
1603  *	@bar: BAR to be reserved
1604  *	@res_name: Name to be associated with resource.
1605  *	@exclusive: whether the region access is exclusive or not
1606  *
1607  *	Mark the PCI region associated with PCI device @pdev BR @bar as
1608  *	being reserved by owner @res_name.  Do not access any
1609  *	address inside the PCI regions unless this call returns
1610  *	successfully.
1611  *
1612  *	If @exclusive is set, then the region is marked so that userspace
1613  *	is explicitly not allowed to map the resource via /dev/mem or
1614  * 	sysfs MMIO access.
1615  *
1616  *	Returns 0 on success, or %EBUSY on error.  A warning
1617  *	message is also printed on failure.
1618  */
1619 static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
1620 									int exclusive)
1621 {
1622 	struct pci_devres *dr;
1623 
1624 	if (pci_resource_len(pdev, bar) == 0)
1625 		return 0;
1626 
1627 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1628 		if (!request_region(pci_resource_start(pdev, bar),
1629 			    pci_resource_len(pdev, bar), res_name))
1630 			goto err_out;
1631 	}
1632 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1633 		if (!__request_mem_region(pci_resource_start(pdev, bar),
1634 					pci_resource_len(pdev, bar), res_name,
1635 					exclusive))
1636 			goto err_out;
1637 	}
1638 
1639 	dr = find_pci_dr(pdev);
1640 	if (dr)
1641 		dr->region_mask |= 1 << bar;
1642 
1643 	return 0;
1644 
1645 err_out:
1646 	dev_warn(&pdev->dev, "BAR %d: can't reserve %s region %pR\n",
1647 		 bar,
1648 		 pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
1649 		 &pdev->resource[bar]);
1650 	return -EBUSY;
1651 }
1652 
1653 /**
1654  *	pci_request_region - Reserve PCI I/O and memory resource
1655  *	@pdev: PCI device whose resources are to be reserved
1656  *	@bar: BAR to be reserved
1657  *	@res_name: Name to be associated with resource
1658  *
1659  *	Mark the PCI region associated with PCI device @pdev BAR @bar as
1660  *	being reserved by owner @res_name.  Do not access any
1661  *	address inside the PCI regions unless this call returns
1662  *	successfully.
1663  *
1664  *	Returns 0 on success, or %EBUSY on error.  A warning
1665  *	message is also printed on failure.
1666  */
1667 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1668 {
1669 	return __pci_request_region(pdev, bar, res_name, 0);
1670 }
1671 
1672 /**
1673  *	pci_request_region_exclusive - Reserved PCI I/O and memory resource
1674  *	@pdev: PCI device whose resources are to be reserved
1675  *	@bar: BAR to be reserved
1676  *	@res_name: Name to be associated with resource.
1677  *
1678  *	Mark the PCI region associated with PCI device @pdev BR @bar as
1679  *	being reserved by owner @res_name.  Do not access any
1680  *	address inside the PCI regions unless this call returns
1681  *	successfully.
1682  *
1683  *	Returns 0 on success, or %EBUSY on error.  A warning
1684  *	message is also printed on failure.
1685  *
1686  *	The key difference that _exclusive makes it that userspace is
1687  *	explicitly not allowed to map the resource via /dev/mem or
1688  * 	sysfs.
1689  */
1690 int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name)
1691 {
1692 	return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
1693 }
1694 /**
1695  * pci_release_selected_regions - Release selected PCI I/O and memory resources
1696  * @pdev: PCI device whose resources were previously reserved
1697  * @bars: Bitmask of BARs to be released
1698  *
1699  * Release selected PCI I/O and memory resources previously reserved.
1700  * Call this function only after all use of the PCI regions has ceased.
1701  */
1702 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1703 {
1704 	int i;
1705 
1706 	for (i = 0; i < 6; i++)
1707 		if (bars & (1 << i))
1708 			pci_release_region(pdev, i);
1709 }
1710 
1711 int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
1712 				 const char *res_name, int excl)
1713 {
1714 	int i;
1715 
1716 	for (i = 0; i < 6; i++)
1717 		if (bars & (1 << i))
1718 			if (__pci_request_region(pdev, i, res_name, excl))
1719 				goto err_out;
1720 	return 0;
1721 
1722 err_out:
1723 	while(--i >= 0)
1724 		if (bars & (1 << i))
1725 			pci_release_region(pdev, i);
1726 
1727 	return -EBUSY;
1728 }
1729 
1730 
1731 /**
1732  * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
1733  * @pdev: PCI device whose resources are to be reserved
1734  * @bars: Bitmask of BARs to be requested
1735  * @res_name: Name to be associated with resource
1736  */
1737 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
1738 				 const char *res_name)
1739 {
1740 	return __pci_request_selected_regions(pdev, bars, res_name, 0);
1741 }
1742 
1743 int pci_request_selected_regions_exclusive(struct pci_dev *pdev,
1744 				 int bars, const char *res_name)
1745 {
1746 	return __pci_request_selected_regions(pdev, bars, res_name,
1747 			IORESOURCE_EXCLUSIVE);
1748 }
1749 
1750 /**
1751  *	pci_release_regions - Release reserved PCI I/O and memory resources
1752  *	@pdev: PCI device whose resources were previously reserved by pci_request_regions
1753  *
1754  *	Releases all PCI I/O and memory resources previously reserved by a
1755  *	successful call to pci_request_regions.  Call this function only
1756  *	after all use of the PCI regions has ceased.
1757  */
1758 
1759 void pci_release_regions(struct pci_dev *pdev)
1760 {
1761 	pci_release_selected_regions(pdev, (1 << 6) - 1);
1762 }
1763 
1764 /**
1765  *	pci_request_regions - Reserved PCI I/O and memory resources
1766  *	@pdev: PCI device whose resources are to be reserved
1767  *	@res_name: Name to be associated with resource.
1768  *
1769  *	Mark all PCI regions associated with PCI device @pdev as
1770  *	being reserved by owner @res_name.  Do not access any
1771  *	address inside the PCI regions unless this call returns
1772  *	successfully.
1773  *
1774  *	Returns 0 on success, or %EBUSY on error.  A warning
1775  *	message is also printed on failure.
1776  */
1777 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
1778 {
1779 	return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
1780 }
1781 
1782 /**
1783  *	pci_request_regions_exclusive - Reserved PCI I/O and memory resources
1784  *	@pdev: PCI device whose resources are to be reserved
1785  *	@res_name: Name to be associated with resource.
1786  *
1787  *	Mark all PCI regions associated with PCI device @pdev as
1788  *	being reserved by owner @res_name.  Do not access any
1789  *	address inside the PCI regions unless this call returns
1790  *	successfully.
1791  *
1792  *	pci_request_regions_exclusive() will mark the region so that
1793  * 	/dev/mem and the sysfs MMIO access will not be allowed.
1794  *
1795  *	Returns 0 on success, or %EBUSY on error.  A warning
1796  *	message is also printed on failure.
1797  */
1798 int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
1799 {
1800 	return pci_request_selected_regions_exclusive(pdev,
1801 					((1 << 6) - 1), res_name);
1802 }
1803 
1804 static void __pci_set_master(struct pci_dev *dev, bool enable)
1805 {
1806 	u16 old_cmd, cmd;
1807 
1808 	pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
1809 	if (enable)
1810 		cmd = old_cmd | PCI_COMMAND_MASTER;
1811 	else
1812 		cmd = old_cmd & ~PCI_COMMAND_MASTER;
1813 	if (cmd != old_cmd) {
1814 		dev_dbg(&dev->dev, "%s bus mastering\n",
1815 			enable ? "enabling" : "disabling");
1816 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1817 	}
1818 	dev->is_busmaster = enable;
1819 }
1820 
1821 /**
1822  * pci_set_master - enables bus-mastering for device dev
1823  * @dev: the PCI device to enable
1824  *
1825  * Enables bus-mastering on the device and calls pcibios_set_master()
1826  * to do the needed arch specific settings.
1827  */
1828 void pci_set_master(struct pci_dev *dev)
1829 {
1830 	__pci_set_master(dev, true);
1831 	pcibios_set_master(dev);
1832 }
1833 
1834 /**
1835  * pci_clear_master - disables bus-mastering for device dev
1836  * @dev: the PCI device to disable
1837  */
1838 void pci_clear_master(struct pci_dev *dev)
1839 {
1840 	__pci_set_master(dev, false);
1841 }
1842 
1843 #ifdef PCI_DISABLE_MWI
1844 int pci_set_mwi(struct pci_dev *dev)
1845 {
1846 	return 0;
1847 }
1848 
1849 int pci_try_set_mwi(struct pci_dev *dev)
1850 {
1851 	return 0;
1852 }
1853 
1854 void pci_clear_mwi(struct pci_dev *dev)
1855 {
1856 }
1857 
1858 #else
1859 
1860 #ifndef PCI_CACHE_LINE_BYTES
1861 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
1862 #endif
1863 
1864 /* This can be overridden by arch code. */
1865 /* Don't forget this is measured in 32-bit words, not bytes */
1866 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
1867 
1868 /**
1869  * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1870  * @dev: the PCI device for which MWI is to be enabled
1871  *
1872  * Helper function for pci_set_mwi.
1873  * Originally copied from drivers/net/acenic.c.
1874  * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1875  *
1876  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1877  */
1878 static int
1879 pci_set_cacheline_size(struct pci_dev *dev)
1880 {
1881 	u8 cacheline_size;
1882 
1883 	if (!pci_cache_line_size)
1884 		return -EINVAL;		/* The system doesn't support MWI. */
1885 
1886 	/* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1887 	   equal to or multiple of the right value. */
1888 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1889 	if (cacheline_size >= pci_cache_line_size &&
1890 	    (cacheline_size % pci_cache_line_size) == 0)
1891 		return 0;
1892 
1893 	/* Write the correct value. */
1894 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1895 	/* Read it back. */
1896 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1897 	if (cacheline_size == pci_cache_line_size)
1898 		return 0;
1899 
1900 	dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
1901 		   "supported\n", pci_cache_line_size << 2);
1902 
1903 	return -EINVAL;
1904 }
1905 
1906 /**
1907  * pci_set_mwi - enables memory-write-invalidate PCI transaction
1908  * @dev: the PCI device for which MWI is enabled
1909  *
1910  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1911  *
1912  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1913  */
1914 int
1915 pci_set_mwi(struct pci_dev *dev)
1916 {
1917 	int rc;
1918 	u16 cmd;
1919 
1920 	rc = pci_set_cacheline_size(dev);
1921 	if (rc)
1922 		return rc;
1923 
1924 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1925 	if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1926 		dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
1927 		cmd |= PCI_COMMAND_INVALIDATE;
1928 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1929 	}
1930 
1931 	return 0;
1932 }
1933 
1934 /**
1935  * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
1936  * @dev: the PCI device for which MWI is enabled
1937  *
1938  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1939  * Callers are not required to check the return value.
1940  *
1941  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1942  */
1943 int pci_try_set_mwi(struct pci_dev *dev)
1944 {
1945 	int rc = pci_set_mwi(dev);
1946 	return rc;
1947 }
1948 
1949 /**
1950  * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1951  * @dev: the PCI device to disable
1952  *
1953  * Disables PCI Memory-Write-Invalidate transaction on the device
1954  */
1955 void
1956 pci_clear_mwi(struct pci_dev *dev)
1957 {
1958 	u16 cmd;
1959 
1960 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1961 	if (cmd & PCI_COMMAND_INVALIDATE) {
1962 		cmd &= ~PCI_COMMAND_INVALIDATE;
1963 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1964 	}
1965 }
1966 #endif /* ! PCI_DISABLE_MWI */
1967 
1968 /**
1969  * pci_intx - enables/disables PCI INTx for device dev
1970  * @pdev: the PCI device to operate on
1971  * @enable: boolean: whether to enable or disable PCI INTx
1972  *
1973  * Enables/disables PCI INTx for device dev
1974  */
1975 void
1976 pci_intx(struct pci_dev *pdev, int enable)
1977 {
1978 	u16 pci_command, new;
1979 
1980 	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1981 
1982 	if (enable) {
1983 		new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1984 	} else {
1985 		new = pci_command | PCI_COMMAND_INTX_DISABLE;
1986 	}
1987 
1988 	if (new != pci_command) {
1989 		struct pci_devres *dr;
1990 
1991 		pci_write_config_word(pdev, PCI_COMMAND, new);
1992 
1993 		dr = find_pci_dr(pdev);
1994 		if (dr && !dr->restore_intx) {
1995 			dr->restore_intx = 1;
1996 			dr->orig_intx = !enable;
1997 		}
1998 	}
1999 }
2000 
2001 /**
2002  * pci_msi_off - disables any msi or msix capabilities
2003  * @dev: the PCI device to operate on
2004  *
2005  * If you want to use msi see pci_enable_msi and friends.
2006  * This is a lower level primitive that allows us to disable
2007  * msi operation at the device level.
2008  */
2009 void pci_msi_off(struct pci_dev *dev)
2010 {
2011 	int pos;
2012 	u16 control;
2013 
2014 	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
2015 	if (pos) {
2016 		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
2017 		control &= ~PCI_MSI_FLAGS_ENABLE;
2018 		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
2019 	}
2020 	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
2021 	if (pos) {
2022 		pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
2023 		control &= ~PCI_MSIX_FLAGS_ENABLE;
2024 		pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
2025 	}
2026 }
2027 
2028 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
2029 /*
2030  * These can be overridden by arch-specific implementations
2031  */
2032 int
2033 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
2034 {
2035 	if (!pci_dma_supported(dev, mask))
2036 		return -EIO;
2037 
2038 	dev->dma_mask = mask;
2039 
2040 	return 0;
2041 }
2042 
2043 int
2044 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
2045 {
2046 	if (!pci_dma_supported(dev, mask))
2047 		return -EIO;
2048 
2049 	dev->dev.coherent_dma_mask = mask;
2050 
2051 	return 0;
2052 }
2053 #endif
2054 
2055 #ifndef HAVE_ARCH_PCI_SET_DMA_MAX_SEGMENT_SIZE
2056 int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
2057 {
2058 	return dma_set_max_seg_size(&dev->dev, size);
2059 }
2060 EXPORT_SYMBOL(pci_set_dma_max_seg_size);
2061 #endif
2062 
2063 #ifndef HAVE_ARCH_PCI_SET_DMA_SEGMENT_BOUNDARY
2064 int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
2065 {
2066 	return dma_set_seg_boundary(&dev->dev, mask);
2067 }
2068 EXPORT_SYMBOL(pci_set_dma_seg_boundary);
2069 #endif
2070 
2071 static int pcie_flr(struct pci_dev *dev, int probe)
2072 {
2073 	int i;
2074 	int pos;
2075 	u32 cap;
2076 	u16 status;
2077 
2078 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
2079 	if (!pos)
2080 		return -ENOTTY;
2081 
2082 	pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP, &cap);
2083 	if (!(cap & PCI_EXP_DEVCAP_FLR))
2084 		return -ENOTTY;
2085 
2086 	if (probe)
2087 		return 0;
2088 
2089 	/* Wait for Transaction Pending bit clean */
2090 	for (i = 0; i < 4; i++) {
2091 		if (i)
2092 			msleep((1 << (i - 1)) * 100);
2093 
2094 		pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &status);
2095 		if (!(status & PCI_EXP_DEVSTA_TRPND))
2096 			goto clear;
2097 	}
2098 
2099 	dev_err(&dev->dev, "transaction is not cleared; "
2100 			"proceeding with reset anyway\n");
2101 
2102 clear:
2103 	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL,
2104 				PCI_EXP_DEVCTL_BCR_FLR);
2105 	msleep(100);
2106 
2107 	return 0;
2108 }
2109 
2110 static int pci_af_flr(struct pci_dev *dev, int probe)
2111 {
2112 	int i;
2113 	int pos;
2114 	u8 cap;
2115 	u8 status;
2116 
2117 	pos = pci_find_capability(dev, PCI_CAP_ID_AF);
2118 	if (!pos)
2119 		return -ENOTTY;
2120 
2121 	pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
2122 	if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
2123 		return -ENOTTY;
2124 
2125 	if (probe)
2126 		return 0;
2127 
2128 	/* Wait for Transaction Pending bit clean */
2129 	for (i = 0; i < 4; i++) {
2130 		if (i)
2131 			msleep((1 << (i - 1)) * 100);
2132 
2133 		pci_read_config_byte(dev, pos + PCI_AF_STATUS, &status);
2134 		if (!(status & PCI_AF_STATUS_TP))
2135 			goto clear;
2136 	}
2137 
2138 	dev_err(&dev->dev, "transaction is not cleared; "
2139 			"proceeding with reset anyway\n");
2140 
2141 clear:
2142 	pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
2143 	msleep(100);
2144 
2145 	return 0;
2146 }
2147 
2148 static int pci_pm_reset(struct pci_dev *dev, int probe)
2149 {
2150 	u16 csr;
2151 
2152 	if (!dev->pm_cap)
2153 		return -ENOTTY;
2154 
2155 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
2156 	if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
2157 		return -ENOTTY;
2158 
2159 	if (probe)
2160 		return 0;
2161 
2162 	if (dev->current_state != PCI_D0)
2163 		return -EINVAL;
2164 
2165 	csr &= ~PCI_PM_CTRL_STATE_MASK;
2166 	csr |= PCI_D3hot;
2167 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
2168 	msleep(pci_pm_d3_delay);
2169 
2170 	csr &= ~PCI_PM_CTRL_STATE_MASK;
2171 	csr |= PCI_D0;
2172 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
2173 	msleep(pci_pm_d3_delay);
2174 
2175 	return 0;
2176 }
2177 
2178 static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
2179 {
2180 	u16 ctrl;
2181 	struct pci_dev *pdev;
2182 
2183 	if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self)
2184 		return -ENOTTY;
2185 
2186 	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
2187 		if (pdev != dev)
2188 			return -ENOTTY;
2189 
2190 	if (probe)
2191 		return 0;
2192 
2193 	pci_read_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, &ctrl);
2194 	ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
2195 	pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
2196 	msleep(100);
2197 
2198 	ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
2199 	pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
2200 	msleep(100);
2201 
2202 	return 0;
2203 }
2204 
2205 static int pci_dev_reset(struct pci_dev *dev, int probe)
2206 {
2207 	int rc;
2208 
2209 	might_sleep();
2210 
2211 	if (!probe) {
2212 		pci_block_user_cfg_access(dev);
2213 		/* block PM suspend, driver probe, etc. */
2214 		down(&dev->dev.sem);
2215 	}
2216 
2217 	rc = pcie_flr(dev, probe);
2218 	if (rc != -ENOTTY)
2219 		goto done;
2220 
2221 	rc = pci_af_flr(dev, probe);
2222 	if (rc != -ENOTTY)
2223 		goto done;
2224 
2225 	rc = pci_pm_reset(dev, probe);
2226 	if (rc != -ENOTTY)
2227 		goto done;
2228 
2229 	rc = pci_parent_bus_reset(dev, probe);
2230 done:
2231 	if (!probe) {
2232 		up(&dev->dev.sem);
2233 		pci_unblock_user_cfg_access(dev);
2234 	}
2235 
2236 	return rc;
2237 }
2238 
2239 /**
2240  * __pci_reset_function - reset a PCI device function
2241  * @dev: PCI device to reset
2242  *
2243  * Some devices allow an individual function to be reset without affecting
2244  * other functions in the same device.  The PCI device must be responsive
2245  * to PCI config space in order to use this function.
2246  *
2247  * The device function is presumed to be unused when this function is called.
2248  * Resetting the device will make the contents of PCI configuration space
2249  * random, so any caller of this must be prepared to reinitialise the
2250  * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
2251  * etc.
2252  *
2253  * Returns 0 if the device function was successfully reset or negative if the
2254  * device doesn't support resetting a single function.
2255  */
2256 int __pci_reset_function(struct pci_dev *dev)
2257 {
2258 	return pci_dev_reset(dev, 0);
2259 }
2260 EXPORT_SYMBOL_GPL(__pci_reset_function);
2261 
2262 /**
2263  * pci_reset_function - quiesce and reset a PCI device function
2264  * @dev: PCI device to reset
2265  *
2266  * Some devices allow an individual function to be reset without affecting
2267  * other functions in the same device.  The PCI device must be responsive
2268  * to PCI config space in order to use this function.
2269  *
2270  * This function does not just reset the PCI portion of a device, but
2271  * clears all the state associated with the device.  This function differs
2272  * from __pci_reset_function in that it saves and restores device state
2273  * over the reset.
2274  *
2275  * Returns 0 if the device function was successfully reset or negative if the
2276  * device doesn't support resetting a single function.
2277  */
2278 int pci_reset_function(struct pci_dev *dev)
2279 {
2280 	int rc;
2281 
2282 	rc = pci_dev_reset(dev, 1);
2283 	if (rc)
2284 		return rc;
2285 
2286 	pci_save_state(dev);
2287 
2288 	/*
2289 	 * both INTx and MSI are disabled after the Interrupt Disable bit
2290 	 * is set and the Bus Master bit is cleared.
2291 	 */
2292 	pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
2293 
2294 	rc = pci_dev_reset(dev, 0);
2295 
2296 	pci_restore_state(dev);
2297 
2298 	return rc;
2299 }
2300 EXPORT_SYMBOL_GPL(pci_reset_function);
2301 
2302 /**
2303  * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
2304  * @dev: PCI device to query
2305  *
2306  * Returns mmrbc: maximum designed memory read count in bytes
2307  *    or appropriate error value.
2308  */
2309 int pcix_get_max_mmrbc(struct pci_dev *dev)
2310 {
2311 	int err, cap;
2312 	u32 stat;
2313 
2314 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2315 	if (!cap)
2316 		return -EINVAL;
2317 
2318 	err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
2319 	if (err)
2320 		return -EINVAL;
2321 
2322 	return (stat & PCI_X_STATUS_MAX_READ) >> 12;
2323 }
2324 EXPORT_SYMBOL(pcix_get_max_mmrbc);
2325 
2326 /**
2327  * pcix_get_mmrbc - get PCI-X maximum memory read byte count
2328  * @dev: PCI device to query
2329  *
2330  * Returns mmrbc: maximum memory read count in bytes
2331  *    or appropriate error value.
2332  */
2333 int pcix_get_mmrbc(struct pci_dev *dev)
2334 {
2335 	int ret, cap;
2336 	u32 cmd;
2337 
2338 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2339 	if (!cap)
2340 		return -EINVAL;
2341 
2342 	ret = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
2343 	if (!ret)
2344 		ret = 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
2345 
2346 	return ret;
2347 }
2348 EXPORT_SYMBOL(pcix_get_mmrbc);
2349 
2350 /**
2351  * pcix_set_mmrbc - set PCI-X maximum memory read byte count
2352  * @dev: PCI device to query
2353  * @mmrbc: maximum memory read count in bytes
2354  *    valid values are 512, 1024, 2048, 4096
2355  *
2356  * If possible sets maximum memory read byte count, some bridges have erratas
2357  * that prevent this.
2358  */
2359 int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
2360 {
2361 	int cap, err = -EINVAL;
2362 	u32 stat, cmd, v, o;
2363 
2364 	if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
2365 		goto out;
2366 
2367 	v = ffs(mmrbc) - 10;
2368 
2369 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2370 	if (!cap)
2371 		goto out;
2372 
2373 	err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
2374 	if (err)
2375 		goto out;
2376 
2377 	if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
2378 		return -E2BIG;
2379 
2380 	err = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
2381 	if (err)
2382 		goto out;
2383 
2384 	o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
2385 	if (o != v) {
2386 		if (v > o && dev->bus &&
2387 		   (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
2388 			return -EIO;
2389 
2390 		cmd &= ~PCI_X_CMD_MAX_READ;
2391 		cmd |= v << 2;
2392 		err = pci_write_config_dword(dev, cap + PCI_X_CMD, cmd);
2393 	}
2394 out:
2395 	return err;
2396 }
2397 EXPORT_SYMBOL(pcix_set_mmrbc);
2398 
2399 /**
2400  * pcie_get_readrq - get PCI Express read request size
2401  * @dev: PCI device to query
2402  *
2403  * Returns maximum memory read request in bytes
2404  *    or appropriate error value.
2405  */
2406 int pcie_get_readrq(struct pci_dev *dev)
2407 {
2408 	int ret, cap;
2409 	u16 ctl;
2410 
2411 	cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
2412 	if (!cap)
2413 		return -EINVAL;
2414 
2415 	ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
2416 	if (!ret)
2417 	ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
2418 
2419 	return ret;
2420 }
2421 EXPORT_SYMBOL(pcie_get_readrq);
2422 
2423 /**
2424  * pcie_set_readrq - set PCI Express maximum memory read request
2425  * @dev: PCI device to query
2426  * @rq: maximum memory read count in bytes
2427  *    valid values are 128, 256, 512, 1024, 2048, 4096
2428  *
2429  * If possible sets maximum read byte count
2430  */
2431 int pcie_set_readrq(struct pci_dev *dev, int rq)
2432 {
2433 	int cap, err = -EINVAL;
2434 	u16 ctl, v;
2435 
2436 	if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
2437 		goto out;
2438 
2439 	v = (ffs(rq) - 8) << 12;
2440 
2441 	cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
2442 	if (!cap)
2443 		goto out;
2444 
2445 	err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
2446 	if (err)
2447 		goto out;
2448 
2449 	if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
2450 		ctl &= ~PCI_EXP_DEVCTL_READRQ;
2451 		ctl |= v;
2452 		err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
2453 	}
2454 
2455 out:
2456 	return err;
2457 }
2458 EXPORT_SYMBOL(pcie_set_readrq);
2459 
2460 /**
2461  * pci_select_bars - Make BAR mask from the type of resource
2462  * @dev: the PCI device for which BAR mask is made
2463  * @flags: resource type mask to be selected
2464  *
2465  * This helper routine makes bar mask from the type of resource.
2466  */
2467 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
2468 {
2469 	int i, bars = 0;
2470 	for (i = 0; i < PCI_NUM_RESOURCES; i++)
2471 		if (pci_resource_flags(dev, i) & flags)
2472 			bars |= (1 << i);
2473 	return bars;
2474 }
2475 
2476 /**
2477  * pci_resource_bar - get position of the BAR associated with a resource
2478  * @dev: the PCI device
2479  * @resno: the resource number
2480  * @type: the BAR type to be filled in
2481  *
2482  * Returns BAR position in config space, or 0 if the BAR is invalid.
2483  */
2484 int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type)
2485 {
2486 	int reg;
2487 
2488 	if (resno < PCI_ROM_RESOURCE) {
2489 		*type = pci_bar_unknown;
2490 		return PCI_BASE_ADDRESS_0 + 4 * resno;
2491 	} else if (resno == PCI_ROM_RESOURCE) {
2492 		*type = pci_bar_mem32;
2493 		return dev->rom_base_reg;
2494 	} else if (resno < PCI_BRIDGE_RESOURCES) {
2495 		/* device specific resource */
2496 		reg = pci_iov_resource_bar(dev, resno, type);
2497 		if (reg)
2498 			return reg;
2499 	}
2500 
2501 	dev_err(&dev->dev, "BAR: invalid resource #%d\n", resno);
2502 	return 0;
2503 }
2504 
2505 #define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
2506 static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
2507 spinlock_t resource_alignment_lock = SPIN_LOCK_UNLOCKED;
2508 
2509 /**
2510  * pci_specified_resource_alignment - get resource alignment specified by user.
2511  * @dev: the PCI device to get
2512  *
2513  * RETURNS: Resource alignment if it is specified.
2514  *          Zero if it is not specified.
2515  */
2516 resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
2517 {
2518 	int seg, bus, slot, func, align_order, count;
2519 	resource_size_t align = 0;
2520 	char *p;
2521 
2522 	spin_lock(&resource_alignment_lock);
2523 	p = resource_alignment_param;
2524 	while (*p) {
2525 		count = 0;
2526 		if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
2527 							p[count] == '@') {
2528 			p += count + 1;
2529 		} else {
2530 			align_order = -1;
2531 		}
2532 		if (sscanf(p, "%x:%x:%x.%x%n",
2533 			&seg, &bus, &slot, &func, &count) != 4) {
2534 			seg = 0;
2535 			if (sscanf(p, "%x:%x.%x%n",
2536 					&bus, &slot, &func, &count) != 3) {
2537 				/* Invalid format */
2538 				printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
2539 					p);
2540 				break;
2541 			}
2542 		}
2543 		p += count;
2544 		if (seg == pci_domain_nr(dev->bus) &&
2545 			bus == dev->bus->number &&
2546 			slot == PCI_SLOT(dev->devfn) &&
2547 			func == PCI_FUNC(dev->devfn)) {
2548 			if (align_order == -1) {
2549 				align = PAGE_SIZE;
2550 			} else {
2551 				align = 1 << align_order;
2552 			}
2553 			/* Found */
2554 			break;
2555 		}
2556 		if (*p != ';' && *p != ',') {
2557 			/* End of param or invalid format */
2558 			break;
2559 		}
2560 		p++;
2561 	}
2562 	spin_unlock(&resource_alignment_lock);
2563 	return align;
2564 }
2565 
2566 /**
2567  * pci_is_reassigndev - check if specified PCI is target device to reassign
2568  * @dev: the PCI device to check
2569  *
2570  * RETURNS: non-zero for PCI device is a target device to reassign,
2571  *          or zero is not.
2572  */
2573 int pci_is_reassigndev(struct pci_dev *dev)
2574 {
2575 	return (pci_specified_resource_alignment(dev) != 0);
2576 }
2577 
2578 ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
2579 {
2580 	if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
2581 		count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
2582 	spin_lock(&resource_alignment_lock);
2583 	strncpy(resource_alignment_param, buf, count);
2584 	resource_alignment_param[count] = '\0';
2585 	spin_unlock(&resource_alignment_lock);
2586 	return count;
2587 }
2588 
2589 ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
2590 {
2591 	size_t count;
2592 	spin_lock(&resource_alignment_lock);
2593 	count = snprintf(buf, size, "%s", resource_alignment_param);
2594 	spin_unlock(&resource_alignment_lock);
2595 	return count;
2596 }
2597 
2598 static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
2599 {
2600 	return pci_get_resource_alignment_param(buf, PAGE_SIZE);
2601 }
2602 
2603 static ssize_t pci_resource_alignment_store(struct bus_type *bus,
2604 					const char *buf, size_t count)
2605 {
2606 	return pci_set_resource_alignment_param(buf, count);
2607 }
2608 
2609 BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
2610 					pci_resource_alignment_store);
2611 
2612 static int __init pci_resource_alignment_sysfs_init(void)
2613 {
2614 	return bus_create_file(&pci_bus_type,
2615 					&bus_attr_resource_alignment);
2616 }
2617 
2618 late_initcall(pci_resource_alignment_sysfs_init);
2619 
2620 static void __devinit pci_no_domains(void)
2621 {
2622 #ifdef CONFIG_PCI_DOMAINS
2623 	pci_domains_supported = 0;
2624 #endif
2625 }
2626 
2627 /**
2628  * pci_ext_cfg_enabled - can we access extended PCI config space?
2629  * @dev: The PCI device of the root bridge.
2630  *
2631  * Returns 1 if we can access PCI extended config space (offsets
2632  * greater than 0xff). This is the default implementation. Architecture
2633  * implementations can override this.
2634  */
2635 int __attribute__ ((weak)) pci_ext_cfg_avail(struct pci_dev *dev)
2636 {
2637 	return 1;
2638 }
2639 
2640 static int __devinit pci_init(void)
2641 {
2642 	struct pci_dev *dev = NULL;
2643 
2644 	while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
2645 		pci_fixup_device(pci_fixup_final, dev);
2646 	}
2647 
2648 	return 0;
2649 }
2650 
2651 static int __init pci_setup(char *str)
2652 {
2653 	while (str) {
2654 		char *k = strchr(str, ',');
2655 		if (k)
2656 			*k++ = 0;
2657 		if (*str && (str = pcibios_setup(str)) && *str) {
2658 			if (!strcmp(str, "nomsi")) {
2659 				pci_no_msi();
2660 			} else if (!strcmp(str, "noaer")) {
2661 				pci_no_aer();
2662 			} else if (!strcmp(str, "nodomains")) {
2663 				pci_no_domains();
2664 			} else if (!strncmp(str, "cbiosize=", 9)) {
2665 				pci_cardbus_io_size = memparse(str + 9, &str);
2666 			} else if (!strncmp(str, "cbmemsize=", 10)) {
2667 				pci_cardbus_mem_size = memparse(str + 10, &str);
2668 			} else if (!strncmp(str, "resource_alignment=", 19)) {
2669 				pci_set_resource_alignment_param(str + 19,
2670 							strlen(str + 19));
2671 			} else if (!strncmp(str, "ecrc=", 5)) {
2672 				pcie_ecrc_get_policy(str + 5);
2673 			} else {
2674 				printk(KERN_ERR "PCI: Unknown option `%s'\n",
2675 						str);
2676 			}
2677 		}
2678 		str = k;
2679 	}
2680 	return 0;
2681 }
2682 early_param("pci", pci_setup);
2683 
2684 device_initcall(pci_init);
2685 
2686 EXPORT_SYMBOL(pci_reenable_device);
2687 EXPORT_SYMBOL(pci_enable_device_io);
2688 EXPORT_SYMBOL(pci_enable_device_mem);
2689 EXPORT_SYMBOL(pci_enable_device);
2690 EXPORT_SYMBOL(pcim_enable_device);
2691 EXPORT_SYMBOL(pcim_pin_device);
2692 EXPORT_SYMBOL(pci_disable_device);
2693 EXPORT_SYMBOL(pci_find_capability);
2694 EXPORT_SYMBOL(pci_bus_find_capability);
2695 EXPORT_SYMBOL(pci_release_regions);
2696 EXPORT_SYMBOL(pci_request_regions);
2697 EXPORT_SYMBOL(pci_request_regions_exclusive);
2698 EXPORT_SYMBOL(pci_release_region);
2699 EXPORT_SYMBOL(pci_request_region);
2700 EXPORT_SYMBOL(pci_request_region_exclusive);
2701 EXPORT_SYMBOL(pci_release_selected_regions);
2702 EXPORT_SYMBOL(pci_request_selected_regions);
2703 EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
2704 EXPORT_SYMBOL(pci_set_master);
2705 EXPORT_SYMBOL(pci_clear_master);
2706 EXPORT_SYMBOL(pci_set_mwi);
2707 EXPORT_SYMBOL(pci_try_set_mwi);
2708 EXPORT_SYMBOL(pci_clear_mwi);
2709 EXPORT_SYMBOL_GPL(pci_intx);
2710 EXPORT_SYMBOL(pci_set_dma_mask);
2711 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
2712 EXPORT_SYMBOL(pci_assign_resource);
2713 EXPORT_SYMBOL(pci_find_parent_resource);
2714 EXPORT_SYMBOL(pci_select_bars);
2715 
2716 EXPORT_SYMBOL(pci_set_power_state);
2717 EXPORT_SYMBOL(pci_save_state);
2718 EXPORT_SYMBOL(pci_restore_state);
2719 EXPORT_SYMBOL(pci_pme_capable);
2720 EXPORT_SYMBOL(pci_pme_active);
2721 EXPORT_SYMBOL(pci_enable_wake);
2722 EXPORT_SYMBOL(pci_wake_from_d3);
2723 EXPORT_SYMBOL(pci_target_state);
2724 EXPORT_SYMBOL(pci_prepare_to_sleep);
2725 EXPORT_SYMBOL(pci_back_from_sleep);
2726 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
2727 
2728