xref: /openbmc/linux/drivers/pci/pci.c (revision 9ac8d3fb)
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 "pci.h"
24 
25 unsigned int pci_pm_d3_delay = 10;
26 
27 #ifdef CONFIG_PCI_DOMAINS
28 int pci_domains_supported = 1;
29 #endif
30 
31 #define DEFAULT_CARDBUS_IO_SIZE		(256)
32 #define DEFAULT_CARDBUS_MEM_SIZE	(64*1024*1024)
33 /* pci=cbmemsize=nnM,cbiosize=nn can override this */
34 unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
35 unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
36 
37 /**
38  * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
39  * @bus: pointer to PCI bus structure to search
40  *
41  * Given a PCI bus, returns the highest PCI bus number present in the set
42  * including the given PCI bus and its list of child PCI buses.
43  */
44 unsigned char pci_bus_max_busnr(struct pci_bus* bus)
45 {
46 	struct list_head *tmp;
47 	unsigned char max, n;
48 
49 	max = bus->subordinate;
50 	list_for_each(tmp, &bus->children) {
51 		n = pci_bus_max_busnr(pci_bus_b(tmp));
52 		if(n > max)
53 			max = n;
54 	}
55 	return max;
56 }
57 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
58 
59 #if 0
60 /**
61  * pci_max_busnr - returns maximum PCI bus number
62  *
63  * Returns the highest PCI bus number present in the system global list of
64  * PCI buses.
65  */
66 unsigned char __devinit
67 pci_max_busnr(void)
68 {
69 	struct pci_bus *bus = NULL;
70 	unsigned char max, n;
71 
72 	max = 0;
73 	while ((bus = pci_find_next_bus(bus)) != NULL) {
74 		n = pci_bus_max_busnr(bus);
75 		if(n > max)
76 			max = n;
77 	}
78 	return max;
79 }
80 
81 #endif  /*  0  */
82 
83 #define PCI_FIND_CAP_TTL	48
84 
85 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
86 				   u8 pos, int cap, int *ttl)
87 {
88 	u8 id;
89 
90 	while ((*ttl)--) {
91 		pci_bus_read_config_byte(bus, devfn, pos, &pos);
92 		if (pos < 0x40)
93 			break;
94 		pos &= ~3;
95 		pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
96 					 &id);
97 		if (id == 0xff)
98 			break;
99 		if (id == cap)
100 			return pos;
101 		pos += PCI_CAP_LIST_NEXT;
102 	}
103 	return 0;
104 }
105 
106 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
107 			       u8 pos, int cap)
108 {
109 	int ttl = PCI_FIND_CAP_TTL;
110 
111 	return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
112 }
113 
114 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
115 {
116 	return __pci_find_next_cap(dev->bus, dev->devfn,
117 				   pos + PCI_CAP_LIST_NEXT, cap);
118 }
119 EXPORT_SYMBOL_GPL(pci_find_next_capability);
120 
121 static int __pci_bus_find_cap_start(struct pci_bus *bus,
122 				    unsigned int devfn, u8 hdr_type)
123 {
124 	u16 status;
125 
126 	pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
127 	if (!(status & PCI_STATUS_CAP_LIST))
128 		return 0;
129 
130 	switch (hdr_type) {
131 	case PCI_HEADER_TYPE_NORMAL:
132 	case PCI_HEADER_TYPE_BRIDGE:
133 		return PCI_CAPABILITY_LIST;
134 	case PCI_HEADER_TYPE_CARDBUS:
135 		return PCI_CB_CAPABILITY_LIST;
136 	default:
137 		return 0;
138 	}
139 
140 	return 0;
141 }
142 
143 /**
144  * pci_find_capability - query for devices' capabilities
145  * @dev: PCI device to query
146  * @cap: capability code
147  *
148  * Tell if a device supports a given PCI capability.
149  * Returns the address of the requested capability structure within the
150  * device's PCI configuration space or 0 in case the device does not
151  * support it.  Possible values for @cap:
152  *
153  *  %PCI_CAP_ID_PM           Power Management
154  *  %PCI_CAP_ID_AGP          Accelerated Graphics Port
155  *  %PCI_CAP_ID_VPD          Vital Product Data
156  *  %PCI_CAP_ID_SLOTID       Slot Identification
157  *  %PCI_CAP_ID_MSI          Message Signalled Interrupts
158  *  %PCI_CAP_ID_CHSWP        CompactPCI HotSwap
159  *  %PCI_CAP_ID_PCIX         PCI-X
160  *  %PCI_CAP_ID_EXP          PCI Express
161  */
162 int pci_find_capability(struct pci_dev *dev, int cap)
163 {
164 	int pos;
165 
166 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
167 	if (pos)
168 		pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
169 
170 	return pos;
171 }
172 
173 /**
174  * pci_bus_find_capability - query for devices' capabilities
175  * @bus:   the PCI bus to query
176  * @devfn: PCI device to query
177  * @cap:   capability code
178  *
179  * Like pci_find_capability() but works for pci devices that do not have a
180  * pci_dev structure set up yet.
181  *
182  * Returns the address of the requested capability structure within the
183  * device's PCI configuration space or 0 in case the device does not
184  * support it.
185  */
186 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
187 {
188 	int pos;
189 	u8 hdr_type;
190 
191 	pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
192 
193 	pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
194 	if (pos)
195 		pos = __pci_find_next_cap(bus, devfn, pos, cap);
196 
197 	return pos;
198 }
199 
200 /**
201  * pci_find_ext_capability - Find an extended capability
202  * @dev: PCI device to query
203  * @cap: capability code
204  *
205  * Returns the address of the requested extended capability structure
206  * within the device's PCI configuration space or 0 if the device does
207  * not support it.  Possible values for @cap:
208  *
209  *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
210  *  %PCI_EXT_CAP_ID_VC		Virtual Channel
211  *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
212  *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
213  */
214 int pci_find_ext_capability(struct pci_dev *dev, int cap)
215 {
216 	u32 header;
217 	int ttl;
218 	int pos = PCI_CFG_SPACE_SIZE;
219 
220 	/* minimum 8 bytes per capability */
221 	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
222 
223 	if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
224 		return 0;
225 
226 	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
227 		return 0;
228 
229 	/*
230 	 * If we have no capabilities, this is indicated by cap ID,
231 	 * cap version and next pointer all being 0.
232 	 */
233 	if (header == 0)
234 		return 0;
235 
236 	while (ttl-- > 0) {
237 		if (PCI_EXT_CAP_ID(header) == cap)
238 			return pos;
239 
240 		pos = PCI_EXT_CAP_NEXT(header);
241 		if (pos < PCI_CFG_SPACE_SIZE)
242 			break;
243 
244 		if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
245 			break;
246 	}
247 
248 	return 0;
249 }
250 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
251 
252 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
253 {
254 	int rc, ttl = PCI_FIND_CAP_TTL;
255 	u8 cap, mask;
256 
257 	if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
258 		mask = HT_3BIT_CAP_MASK;
259 	else
260 		mask = HT_5BIT_CAP_MASK;
261 
262 	pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
263 				      PCI_CAP_ID_HT, &ttl);
264 	while (pos) {
265 		rc = pci_read_config_byte(dev, pos + 3, &cap);
266 		if (rc != PCIBIOS_SUCCESSFUL)
267 			return 0;
268 
269 		if ((cap & mask) == ht_cap)
270 			return pos;
271 
272 		pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
273 					      pos + PCI_CAP_LIST_NEXT,
274 					      PCI_CAP_ID_HT, &ttl);
275 	}
276 
277 	return 0;
278 }
279 /**
280  * pci_find_next_ht_capability - query a device's Hypertransport capabilities
281  * @dev: PCI device to query
282  * @pos: Position from which to continue searching
283  * @ht_cap: Hypertransport capability code
284  *
285  * To be used in conjunction with pci_find_ht_capability() to search for
286  * all capabilities matching @ht_cap. @pos should always be a value returned
287  * from pci_find_ht_capability().
288  *
289  * NB. To be 100% safe against broken PCI devices, the caller should take
290  * steps to avoid an infinite loop.
291  */
292 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
293 {
294 	return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
295 }
296 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
297 
298 /**
299  * pci_find_ht_capability - query a device's Hypertransport capabilities
300  * @dev: PCI device to query
301  * @ht_cap: Hypertransport capability code
302  *
303  * Tell if a device supports a given Hypertransport capability.
304  * Returns an address within the device's PCI configuration space
305  * or 0 in case the device does not support the request capability.
306  * The address points to the PCI capability, of type PCI_CAP_ID_HT,
307  * which has a Hypertransport capability matching @ht_cap.
308  */
309 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
310 {
311 	int pos;
312 
313 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
314 	if (pos)
315 		pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
316 
317 	return pos;
318 }
319 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
320 
321 /**
322  * pci_find_parent_resource - return resource region of parent bus of given region
323  * @dev: PCI device structure contains resources to be searched
324  * @res: child resource record for which parent is sought
325  *
326  *  For given resource region of given device, return the resource
327  *  region of parent bus the given region is contained in or where
328  *  it should be allocated from.
329  */
330 struct resource *
331 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
332 {
333 	const struct pci_bus *bus = dev->bus;
334 	int i;
335 	struct resource *best = NULL;
336 
337 	for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
338 		struct resource *r = bus->resource[i];
339 		if (!r)
340 			continue;
341 		if (res->start && !(res->start >= r->start && res->end <= r->end))
342 			continue;	/* Not contained */
343 		if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
344 			continue;	/* Wrong type */
345 		if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
346 			return r;	/* Exact match */
347 		if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
348 			best = r;	/* Approximating prefetchable by non-prefetchable */
349 	}
350 	return best;
351 }
352 
353 /**
354  * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
355  * @dev: PCI device to have its BARs restored
356  *
357  * Restore the BAR values for a given device, so as to make it
358  * accessible by its driver.
359  */
360 static void
361 pci_restore_bars(struct pci_dev *dev)
362 {
363 	int i, numres;
364 
365 	switch (dev->hdr_type) {
366 	case PCI_HEADER_TYPE_NORMAL:
367 		numres = 6;
368 		break;
369 	case PCI_HEADER_TYPE_BRIDGE:
370 		numres = 2;
371 		break;
372 	case PCI_HEADER_TYPE_CARDBUS:
373 		numres = 1;
374 		break;
375 	default:
376 		/* Should never get here, but just in case... */
377 		return;
378 	}
379 
380 	for (i = 0; i < numres; i ++)
381 		pci_update_resource(dev, &dev->resource[i], i);
382 }
383 
384 static struct pci_platform_pm_ops *pci_platform_pm;
385 
386 int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
387 {
388 	if (!ops->is_manageable || !ops->set_state || !ops->choose_state
389 	    || !ops->sleep_wake || !ops->can_wakeup)
390 		return -EINVAL;
391 	pci_platform_pm = ops;
392 	return 0;
393 }
394 
395 static inline bool platform_pci_power_manageable(struct pci_dev *dev)
396 {
397 	return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
398 }
399 
400 static inline int platform_pci_set_power_state(struct pci_dev *dev,
401                                                 pci_power_t t)
402 {
403 	return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
404 }
405 
406 static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
407 {
408 	return pci_platform_pm ?
409 			pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
410 }
411 
412 static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
413 {
414 	return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
415 }
416 
417 static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
418 {
419 	return pci_platform_pm ?
420 			pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
421 }
422 
423 /**
424  * pci_raw_set_power_state - Use PCI PM registers to set the power state of
425  *                           given PCI device
426  * @dev: PCI device to handle.
427  * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
428  *
429  * RETURN VALUE:
430  * -EINVAL if the requested state is invalid.
431  * -EIO if device does not support PCI PM or its PM capabilities register has a
432  * wrong version, or device doesn't support the requested state.
433  * 0 if device already is in the requested state.
434  * 0 if device's power state has been successfully changed.
435  */
436 static int
437 pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
438 {
439 	u16 pmcsr;
440 	bool need_restore = false;
441 
442 	if (!dev->pm_cap)
443 		return -EIO;
444 
445 	if (state < PCI_D0 || state > PCI_D3hot)
446 		return -EINVAL;
447 
448 	/* Validate current state:
449 	 * Can enter D0 from any state, but if we can only go deeper
450 	 * to sleep if we're already in a low power state
451 	 */
452 	if (dev->current_state == state) {
453 		/* we're already there */
454 		return 0;
455 	} else if (state != PCI_D0 && dev->current_state <= PCI_D3cold
456 	    && dev->current_state > state) {
457 		dev_err(&dev->dev, "invalid power transition "
458 			"(from state %d to %d)\n", dev->current_state, state);
459 		return -EINVAL;
460 	}
461 
462 	/* check if this device supports the desired state */
463 	if ((state == PCI_D1 && !dev->d1_support)
464 	   || (state == PCI_D2 && !dev->d2_support))
465 		return -EIO;
466 
467 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
468 
469 	/* If we're (effectively) in D3, force entire word to 0.
470 	 * This doesn't affect PME_Status, disables PME_En, and
471 	 * sets PowerState to 0.
472 	 */
473 	switch (dev->current_state) {
474 	case PCI_D0:
475 	case PCI_D1:
476 	case PCI_D2:
477 		pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
478 		pmcsr |= state;
479 		break;
480 	case PCI_UNKNOWN: /* Boot-up */
481 		if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
482 		 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
483 			need_restore = true;
484 		/* Fall-through: force to D0 */
485 	default:
486 		pmcsr = 0;
487 		break;
488 	}
489 
490 	/* enter specified state */
491 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
492 
493 	/* Mandatory power management transition delays */
494 	/* see PCI PM 1.1 5.6.1 table 18 */
495 	if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
496 		msleep(pci_pm_d3_delay);
497 	else if (state == PCI_D2 || dev->current_state == PCI_D2)
498 		udelay(200);
499 
500 	dev->current_state = state;
501 
502 	/* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
503 	 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
504 	 * from D3hot to D0 _may_ perform an internal reset, thereby
505 	 * going to "D0 Uninitialized" rather than "D0 Initialized".
506 	 * For example, at least some versions of the 3c905B and the
507 	 * 3c556B exhibit this behaviour.
508 	 *
509 	 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
510 	 * devices in a D3hot state at boot.  Consequently, we need to
511 	 * restore at least the BARs so that the device will be
512 	 * accessible to its driver.
513 	 */
514 	if (need_restore)
515 		pci_restore_bars(dev);
516 
517 	if (dev->bus->self)
518 		pcie_aspm_pm_state_change(dev->bus->self);
519 
520 	return 0;
521 }
522 
523 /**
524  * pci_update_current_state - Read PCI power state of given device from its
525  *                            PCI PM registers and cache it
526  * @dev: PCI device to handle.
527  */
528 static void pci_update_current_state(struct pci_dev *dev)
529 {
530 	if (dev->pm_cap) {
531 		u16 pmcsr;
532 
533 		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
534 		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
535 	}
536 }
537 
538 /**
539  * pci_set_power_state - Set the power state of a PCI device
540  * @dev: PCI device to handle.
541  * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
542  *
543  * Transition a device to a new power state, using the platform formware and/or
544  * the device's PCI PM registers.
545  *
546  * RETURN VALUE:
547  * -EINVAL if the requested state is invalid.
548  * -EIO if device does not support PCI PM or its PM capabilities register has a
549  * wrong version, or device doesn't support the requested state.
550  * 0 if device already is in the requested state.
551  * 0 if device's power state has been successfully changed.
552  */
553 int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
554 {
555 	int error;
556 
557 	/* bound the state we're entering */
558 	if (state > PCI_D3hot)
559 		state = PCI_D3hot;
560 	else if (state < PCI_D0)
561 		state = PCI_D0;
562 	else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
563 		/*
564 		 * If the device or the parent bridge do not support PCI PM,
565 		 * ignore the request if we're doing anything other than putting
566 		 * it into D0 (which would only happen on boot).
567 		 */
568 		return 0;
569 
570 	if (state == PCI_D0 && platform_pci_power_manageable(dev)) {
571 		/*
572 		 * Allow the platform to change the state, for example via ACPI
573 		 * _PR0, _PS0 and some such, but do not trust it.
574 		 */
575 		int ret = platform_pci_set_power_state(dev, PCI_D0);
576 		if (!ret)
577 			pci_update_current_state(dev);
578 	}
579 	/* This device is quirked not to be put into D3, so
580 	   don't put it in D3 */
581 	if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
582 		return 0;
583 
584 	error = pci_raw_set_power_state(dev, state);
585 
586 	if (state > PCI_D0 && platform_pci_power_manageable(dev)) {
587 		/* Allow the platform to finalize the transition */
588 		int ret = platform_pci_set_power_state(dev, state);
589 		if (!ret) {
590 			pci_update_current_state(dev);
591 			error = 0;
592 		}
593 	}
594 
595 	return error;
596 }
597 
598 /**
599  * pci_choose_state - Choose the power state of a PCI device
600  * @dev: PCI device to be suspended
601  * @state: target sleep state for the whole system. This is the value
602  *	that is passed to suspend() function.
603  *
604  * Returns PCI power state suitable for given device and given system
605  * message.
606  */
607 
608 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
609 {
610 	pci_power_t ret;
611 
612 	if (!pci_find_capability(dev, PCI_CAP_ID_PM))
613 		return PCI_D0;
614 
615 	ret = platform_pci_choose_state(dev);
616 	if (ret != PCI_POWER_ERROR)
617 		return ret;
618 
619 	switch (state.event) {
620 	case PM_EVENT_ON:
621 		return PCI_D0;
622 	case PM_EVENT_FREEZE:
623 	case PM_EVENT_PRETHAW:
624 		/* REVISIT both freeze and pre-thaw "should" use D0 */
625 	case PM_EVENT_SUSPEND:
626 	case PM_EVENT_HIBERNATE:
627 		return PCI_D3hot;
628 	default:
629 		dev_info(&dev->dev, "unrecognized suspend event %d\n",
630 			 state.event);
631 		BUG();
632 	}
633 	return PCI_D0;
634 }
635 
636 EXPORT_SYMBOL(pci_choose_state);
637 
638 static int pci_save_pcie_state(struct pci_dev *dev)
639 {
640 	int pos, i = 0;
641 	struct pci_cap_saved_state *save_state;
642 	u16 *cap;
643 	int found = 0;
644 
645 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
646 	if (pos <= 0)
647 		return 0;
648 
649 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
650 	if (!save_state)
651 		save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);
652 	else
653 		found = 1;
654 	if (!save_state) {
655 		dev_err(&dev->dev, "out of memory in pci_save_pcie_state\n");
656 		return -ENOMEM;
657 	}
658 	cap = (u16 *)&save_state->data[0];
659 
660 	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
661 	pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
662 	pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
663 	pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
664 	save_state->cap_nr = PCI_CAP_ID_EXP;
665 	if (!found)
666 		pci_add_saved_cap(dev, save_state);
667 	return 0;
668 }
669 
670 static void pci_restore_pcie_state(struct pci_dev *dev)
671 {
672 	int i = 0, pos;
673 	struct pci_cap_saved_state *save_state;
674 	u16 *cap;
675 
676 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
677 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
678 	if (!save_state || pos <= 0)
679 		return;
680 	cap = (u16 *)&save_state->data[0];
681 
682 	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
683 	pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
684 	pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
685 	pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
686 }
687 
688 
689 static int pci_save_pcix_state(struct pci_dev *dev)
690 {
691 	int pos, i = 0;
692 	struct pci_cap_saved_state *save_state;
693 	u16 *cap;
694 	int found = 0;
695 
696 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
697 	if (pos <= 0)
698 		return 0;
699 
700 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
701 	if (!save_state)
702 		save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);
703 	else
704 		found = 1;
705 	if (!save_state) {
706 		dev_err(&dev->dev, "out of memory in pci_save_pcie_state\n");
707 		return -ENOMEM;
708 	}
709 	cap = (u16 *)&save_state->data[0];
710 
711 	pci_read_config_word(dev, pos + PCI_X_CMD, &cap[i++]);
712 	save_state->cap_nr = PCI_CAP_ID_PCIX;
713 	if (!found)
714 		pci_add_saved_cap(dev, save_state);
715 	return 0;
716 }
717 
718 static void pci_restore_pcix_state(struct pci_dev *dev)
719 {
720 	int i = 0, pos;
721 	struct pci_cap_saved_state *save_state;
722 	u16 *cap;
723 
724 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
725 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
726 	if (!save_state || pos <= 0)
727 		return;
728 	cap = (u16 *)&save_state->data[0];
729 
730 	pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
731 }
732 
733 
734 /**
735  * pci_save_state - save the PCI configuration space of a device before suspending
736  * @dev: - PCI device that we're dealing with
737  */
738 int
739 pci_save_state(struct pci_dev *dev)
740 {
741 	int i;
742 	/* XXX: 100% dword access ok here? */
743 	for (i = 0; i < 16; i++)
744 		pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
745 	if ((i = pci_save_pcie_state(dev)) != 0)
746 		return i;
747 	if ((i = pci_save_pcix_state(dev)) != 0)
748 		return i;
749 	return 0;
750 }
751 
752 /**
753  * pci_restore_state - Restore the saved state of a PCI device
754  * @dev: - PCI device that we're dealing with
755  */
756 int
757 pci_restore_state(struct pci_dev *dev)
758 {
759 	int i;
760 	u32 val;
761 
762 	/* PCI Express register must be restored first */
763 	pci_restore_pcie_state(dev);
764 
765 	/*
766 	 * The Base Address register should be programmed before the command
767 	 * register(s)
768 	 */
769 	for (i = 15; i >= 0; i--) {
770 		pci_read_config_dword(dev, i * 4, &val);
771 		if (val != dev->saved_config_space[i]) {
772 			dev_printk(KERN_DEBUG, &dev->dev, "restoring config "
773 				"space at offset %#x (was %#x, writing %#x)\n",
774 				i, val, (int)dev->saved_config_space[i]);
775 			pci_write_config_dword(dev,i * 4,
776 				dev->saved_config_space[i]);
777 		}
778 	}
779 	pci_restore_pcix_state(dev);
780 	pci_restore_msi_state(dev);
781 
782 	return 0;
783 }
784 
785 static int do_pci_enable_device(struct pci_dev *dev, int bars)
786 {
787 	int err;
788 
789 	err = pci_set_power_state(dev, PCI_D0);
790 	if (err < 0 && err != -EIO)
791 		return err;
792 	err = pcibios_enable_device(dev, bars);
793 	if (err < 0)
794 		return err;
795 	pci_fixup_device(pci_fixup_enable, dev);
796 
797 	return 0;
798 }
799 
800 /**
801  * pci_reenable_device - Resume abandoned device
802  * @dev: PCI device to be resumed
803  *
804  *  Note this function is a backend of pci_default_resume and is not supposed
805  *  to be called by normal code, write proper resume handler and use it instead.
806  */
807 int pci_reenable_device(struct pci_dev *dev)
808 {
809 	if (atomic_read(&dev->enable_cnt))
810 		return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
811 	return 0;
812 }
813 
814 static int __pci_enable_device_flags(struct pci_dev *dev,
815 				     resource_size_t flags)
816 {
817 	int err;
818 	int i, bars = 0;
819 
820 	if (atomic_add_return(1, &dev->enable_cnt) > 1)
821 		return 0;		/* already enabled */
822 
823 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
824 		if (dev->resource[i].flags & flags)
825 			bars |= (1 << i);
826 
827 	err = do_pci_enable_device(dev, bars);
828 	if (err < 0)
829 		atomic_dec(&dev->enable_cnt);
830 	return err;
831 }
832 
833 /**
834  * pci_enable_device_io - Initialize a device for use with IO space
835  * @dev: PCI device to be initialized
836  *
837  *  Initialize device before it's used by a driver. Ask low-level code
838  *  to enable I/O resources. Wake up the device if it was suspended.
839  *  Beware, this function can fail.
840  */
841 int pci_enable_device_io(struct pci_dev *dev)
842 {
843 	return __pci_enable_device_flags(dev, IORESOURCE_IO);
844 }
845 
846 /**
847  * pci_enable_device_mem - Initialize a device for use with Memory space
848  * @dev: PCI device to be initialized
849  *
850  *  Initialize device before it's used by a driver. Ask low-level code
851  *  to enable Memory resources. Wake up the device if it was suspended.
852  *  Beware, this function can fail.
853  */
854 int pci_enable_device_mem(struct pci_dev *dev)
855 {
856 	return __pci_enable_device_flags(dev, IORESOURCE_MEM);
857 }
858 
859 /**
860  * pci_enable_device - Initialize device before it's used by a driver.
861  * @dev: PCI device to be initialized
862  *
863  *  Initialize device before it's used by a driver. Ask low-level code
864  *  to enable I/O and memory. Wake up the device if it was suspended.
865  *  Beware, this function can fail.
866  *
867  *  Note we don't actually enable the device many times if we call
868  *  this function repeatedly (we just increment the count).
869  */
870 int pci_enable_device(struct pci_dev *dev)
871 {
872 	return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
873 }
874 
875 /*
876  * Managed PCI resources.  This manages device on/off, intx/msi/msix
877  * on/off and BAR regions.  pci_dev itself records msi/msix status, so
878  * there's no need to track it separately.  pci_devres is initialized
879  * when a device is enabled using managed PCI device enable interface.
880  */
881 struct pci_devres {
882 	unsigned int enabled:1;
883 	unsigned int pinned:1;
884 	unsigned int orig_intx:1;
885 	unsigned int restore_intx:1;
886 	u32 region_mask;
887 };
888 
889 static void pcim_release(struct device *gendev, void *res)
890 {
891 	struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
892 	struct pci_devres *this = res;
893 	int i;
894 
895 	if (dev->msi_enabled)
896 		pci_disable_msi(dev);
897 	if (dev->msix_enabled)
898 		pci_disable_msix(dev);
899 
900 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
901 		if (this->region_mask & (1 << i))
902 			pci_release_region(dev, i);
903 
904 	if (this->restore_intx)
905 		pci_intx(dev, this->orig_intx);
906 
907 	if (this->enabled && !this->pinned)
908 		pci_disable_device(dev);
909 }
910 
911 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
912 {
913 	struct pci_devres *dr, *new_dr;
914 
915 	dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
916 	if (dr)
917 		return dr;
918 
919 	new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
920 	if (!new_dr)
921 		return NULL;
922 	return devres_get(&pdev->dev, new_dr, NULL, NULL);
923 }
924 
925 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
926 {
927 	if (pci_is_managed(pdev))
928 		return devres_find(&pdev->dev, pcim_release, NULL, NULL);
929 	return NULL;
930 }
931 
932 /**
933  * pcim_enable_device - Managed pci_enable_device()
934  * @pdev: PCI device to be initialized
935  *
936  * Managed pci_enable_device().
937  */
938 int pcim_enable_device(struct pci_dev *pdev)
939 {
940 	struct pci_devres *dr;
941 	int rc;
942 
943 	dr = get_pci_dr(pdev);
944 	if (unlikely(!dr))
945 		return -ENOMEM;
946 	if (dr->enabled)
947 		return 0;
948 
949 	rc = pci_enable_device(pdev);
950 	if (!rc) {
951 		pdev->is_managed = 1;
952 		dr->enabled = 1;
953 	}
954 	return rc;
955 }
956 
957 /**
958  * pcim_pin_device - Pin managed PCI device
959  * @pdev: PCI device to pin
960  *
961  * Pin managed PCI device @pdev.  Pinned device won't be disabled on
962  * driver detach.  @pdev must have been enabled with
963  * pcim_enable_device().
964  */
965 void pcim_pin_device(struct pci_dev *pdev)
966 {
967 	struct pci_devres *dr;
968 
969 	dr = find_pci_dr(pdev);
970 	WARN_ON(!dr || !dr->enabled);
971 	if (dr)
972 		dr->pinned = 1;
973 }
974 
975 /**
976  * pcibios_disable_device - disable arch specific PCI resources for device dev
977  * @dev: the PCI device to disable
978  *
979  * Disables architecture specific PCI resources for the device. This
980  * is the default implementation. Architecture implementations can
981  * override this.
982  */
983 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
984 
985 /**
986  * pci_disable_device - Disable PCI device after use
987  * @dev: PCI device to be disabled
988  *
989  * Signal to the system that the PCI device is not in use by the system
990  * anymore.  This only involves disabling PCI bus-mastering, if active.
991  *
992  * Note we don't actually disable the device until all callers of
993  * pci_device_enable() have called pci_device_disable().
994  */
995 void
996 pci_disable_device(struct pci_dev *dev)
997 {
998 	struct pci_devres *dr;
999 	u16 pci_command;
1000 
1001 	dr = find_pci_dr(dev);
1002 	if (dr)
1003 		dr->enabled = 0;
1004 
1005 	if (atomic_sub_return(1, &dev->enable_cnt) != 0)
1006 		return;
1007 
1008 	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1009 	if (pci_command & PCI_COMMAND_MASTER) {
1010 		pci_command &= ~PCI_COMMAND_MASTER;
1011 		pci_write_config_word(dev, PCI_COMMAND, pci_command);
1012 	}
1013 	dev->is_busmaster = 0;
1014 
1015 	pcibios_disable_device(dev);
1016 }
1017 
1018 /**
1019  * pcibios_set_pcie_reset_state - set reset state for device dev
1020  * @dev: the PCI-E device reset
1021  * @state: Reset state to enter into
1022  *
1023  *
1024  * Sets the PCI-E reset state for the device. This is the default
1025  * implementation. Architecture implementations can override this.
1026  */
1027 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
1028 							enum pcie_reset_state state)
1029 {
1030 	return -EINVAL;
1031 }
1032 
1033 /**
1034  * pci_set_pcie_reset_state - set reset state for device dev
1035  * @dev: the PCI-E device reset
1036  * @state: Reset state to enter into
1037  *
1038  *
1039  * Sets the PCI reset state for the device.
1040  */
1041 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1042 {
1043 	return pcibios_set_pcie_reset_state(dev, state);
1044 }
1045 
1046 /**
1047  * pci_pme_capable - check the capability of PCI device to generate PME#
1048  * @dev: PCI device to handle.
1049  * @state: PCI state from which device will issue PME#.
1050  */
1051 bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1052 {
1053 	if (!dev->pm_cap)
1054 		return false;
1055 
1056 	return !!(dev->pme_support & (1 << state));
1057 }
1058 
1059 /**
1060  * pci_pme_active - enable or disable PCI device's PME# function
1061  * @dev: PCI device to handle.
1062  * @enable: 'true' to enable PME# generation; 'false' to disable it.
1063  *
1064  * The caller must verify that the device is capable of generating PME# before
1065  * calling this function with @enable equal to 'true'.
1066  */
1067 void pci_pme_active(struct pci_dev *dev, bool enable)
1068 {
1069 	u16 pmcsr;
1070 
1071 	if (!dev->pm_cap)
1072 		return;
1073 
1074 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1075 	/* Clear PME_Status by writing 1 to it and enable PME# */
1076 	pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1077 	if (!enable)
1078 		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1079 
1080 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1081 
1082 	dev_printk(KERN_INFO, &dev->dev, "PME# %s\n",
1083 			enable ? "enabled" : "disabled");
1084 }
1085 
1086 /**
1087  * pci_enable_wake - enable PCI device as wakeup event source
1088  * @dev: PCI device affected
1089  * @state: PCI state from which device will issue wakeup events
1090  * @enable: True to enable event generation; false to disable
1091  *
1092  * This enables the device as a wakeup event source, or disables it.
1093  * When such events involves platform-specific hooks, those hooks are
1094  * called automatically by this routine.
1095  *
1096  * Devices with legacy power management (no standard PCI PM capabilities)
1097  * always require such platform hooks.
1098  *
1099  * RETURN VALUE:
1100  * 0 is returned on success
1101  * -EINVAL is returned if device is not supposed to wake up the system
1102  * Error code depending on the platform is returned if both the platform and
1103  * the native mechanism fail to enable the generation of wake-up events
1104  */
1105 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
1106 {
1107 	int error = 0;
1108 	bool pme_done = false;
1109 
1110 	if (!device_may_wakeup(&dev->dev))
1111 		return -EINVAL;
1112 
1113 	/*
1114 	 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1115 	 * Anderson we should be doing PME# wake enable followed by ACPI wake
1116 	 * enable.  To disable wake-up we call the platform first, for symmetry.
1117 	 */
1118 
1119 	if (!enable && platform_pci_can_wakeup(dev))
1120 		error = platform_pci_sleep_wake(dev, false);
1121 
1122 	if (!enable || pci_pme_capable(dev, state)) {
1123 		pci_pme_active(dev, enable);
1124 		pme_done = true;
1125 	}
1126 
1127 	if (enable && platform_pci_can_wakeup(dev))
1128 		error = platform_pci_sleep_wake(dev, true);
1129 
1130 	return pme_done ? 0 : error;
1131 }
1132 
1133 /**
1134  * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1135  * @dev: PCI device to prepare
1136  * @enable: True to enable wake-up event generation; false to disable
1137  *
1138  * Many drivers want the device to wake up the system from D3_hot or D3_cold
1139  * and this function allows them to set that up cleanly - pci_enable_wake()
1140  * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1141  * ordering constraints.
1142  *
1143  * This function only returns error code if the device is not capable of
1144  * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1145  * enable wake-up power for it.
1146  */
1147 int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1148 {
1149 	return pci_pme_capable(dev, PCI_D3cold) ?
1150 			pci_enable_wake(dev, PCI_D3cold, enable) :
1151 			pci_enable_wake(dev, PCI_D3hot, enable);
1152 }
1153 
1154 /**
1155  * pci_target_state - find an appropriate low power state for a given PCI dev
1156  * @dev: PCI device
1157  *
1158  * Use underlying platform code to find a supported low power state for @dev.
1159  * If the platform can't manage @dev, return the deepest state from which it
1160  * can generate wake events, based on any available PME info.
1161  */
1162 pci_power_t pci_target_state(struct pci_dev *dev)
1163 {
1164 	pci_power_t target_state = PCI_D3hot;
1165 
1166 	if (platform_pci_power_manageable(dev)) {
1167 		/*
1168 		 * Call the platform to choose the target state of the device
1169 		 * and enable wake-up from this state if supported.
1170 		 */
1171 		pci_power_t state = platform_pci_choose_state(dev);
1172 
1173 		switch (state) {
1174 		case PCI_POWER_ERROR:
1175 		case PCI_UNKNOWN:
1176 			break;
1177 		case PCI_D1:
1178 		case PCI_D2:
1179 			if (pci_no_d1d2(dev))
1180 				break;
1181 		default:
1182 			target_state = state;
1183 		}
1184 	} else if (device_may_wakeup(&dev->dev)) {
1185 		/*
1186 		 * Find the deepest state from which the device can generate
1187 		 * wake-up events, make it the target state and enable device
1188 		 * to generate PME#.
1189 		 */
1190 		if (!dev->pm_cap)
1191 			return PCI_POWER_ERROR;
1192 
1193 		if (dev->pme_support) {
1194 			while (target_state
1195 			      && !(dev->pme_support & (1 << target_state)))
1196 				target_state--;
1197 		}
1198 	}
1199 
1200 	return target_state;
1201 }
1202 
1203 /**
1204  * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1205  * @dev: Device to handle.
1206  *
1207  * Choose the power state appropriate for the device depending on whether
1208  * it can wake up the system and/or is power manageable by the platform
1209  * (PCI_D3hot is the default) and put the device into that state.
1210  */
1211 int pci_prepare_to_sleep(struct pci_dev *dev)
1212 {
1213 	pci_power_t target_state = pci_target_state(dev);
1214 	int error;
1215 
1216 	if (target_state == PCI_POWER_ERROR)
1217 		return -EIO;
1218 
1219 	pci_enable_wake(dev, target_state, true);
1220 
1221 	error = pci_set_power_state(dev, target_state);
1222 
1223 	if (error)
1224 		pci_enable_wake(dev, target_state, false);
1225 
1226 	return error;
1227 }
1228 
1229 /**
1230  * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1231  * @dev: Device to handle.
1232  *
1233  * Disable device's sytem wake-up capability and put it into D0.
1234  */
1235 int pci_back_from_sleep(struct pci_dev *dev)
1236 {
1237 	pci_enable_wake(dev, PCI_D0, false);
1238 	return pci_set_power_state(dev, PCI_D0);
1239 }
1240 
1241 /**
1242  * pci_pm_init - Initialize PM functions of given PCI device
1243  * @dev: PCI device to handle.
1244  */
1245 void pci_pm_init(struct pci_dev *dev)
1246 {
1247 	int pm;
1248 	u16 pmc;
1249 
1250 	dev->pm_cap = 0;
1251 
1252 	/* find PCI PM capability in list */
1253 	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
1254 	if (!pm)
1255 		return;
1256 	/* Check device's ability to generate PME# */
1257 	pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
1258 
1259 	if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
1260 		dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
1261 			pmc & PCI_PM_CAP_VER_MASK);
1262 		return;
1263 	}
1264 
1265 	dev->pm_cap = pm;
1266 
1267 	dev->d1_support = false;
1268 	dev->d2_support = false;
1269 	if (!pci_no_d1d2(dev)) {
1270 		if (pmc & PCI_PM_CAP_D1)
1271 			dev->d1_support = true;
1272 		if (pmc & PCI_PM_CAP_D2)
1273 			dev->d2_support = true;
1274 
1275 		if (dev->d1_support || dev->d2_support)
1276 			dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
1277 				   dev->d1_support ? " D1" : "",
1278 				   dev->d2_support ? " D2" : "");
1279 	}
1280 
1281 	pmc &= PCI_PM_CAP_PME_MASK;
1282 	if (pmc) {
1283 		dev_info(&dev->dev, "PME# supported from%s%s%s%s%s\n",
1284 			 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
1285 			 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
1286 			 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
1287 			 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
1288 			 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
1289 		dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
1290 		/*
1291 		 * Make device's PM flags reflect the wake-up capability, but
1292 		 * let the user space enable it to wake up the system as needed.
1293 		 */
1294 		device_set_wakeup_capable(&dev->dev, true);
1295 		device_set_wakeup_enable(&dev->dev, false);
1296 		/* Disable the PME# generation functionality */
1297 		pci_pme_active(dev, false);
1298 	} else {
1299 		dev->pme_support = 0;
1300 	}
1301 }
1302 
1303 /**
1304  * pci_enable_ari - enable ARI forwarding if hardware support it
1305  * @dev: the PCI device
1306  */
1307 void pci_enable_ari(struct pci_dev *dev)
1308 {
1309 	int pos;
1310 	u32 cap;
1311 	u16 ctrl;
1312 	struct pci_dev *bridge;
1313 
1314 	if (!dev->is_pcie || dev->devfn)
1315 		return;
1316 
1317 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1318 	if (!pos)
1319 		return;
1320 
1321 	bridge = dev->bus->self;
1322 	if (!bridge || !bridge->is_pcie)
1323 		return;
1324 
1325 	pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
1326 	if (!pos)
1327 		return;
1328 
1329 	pci_read_config_dword(bridge, pos + PCI_EXP_DEVCAP2, &cap);
1330 	if (!(cap & PCI_EXP_DEVCAP2_ARI))
1331 		return;
1332 
1333 	pci_read_config_word(bridge, pos + PCI_EXP_DEVCTL2, &ctrl);
1334 	ctrl |= PCI_EXP_DEVCTL2_ARI;
1335 	pci_write_config_word(bridge, pos + PCI_EXP_DEVCTL2, ctrl);
1336 
1337 	bridge->ari_enabled = 1;
1338 }
1339 
1340 int
1341 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
1342 {
1343 	u8 pin;
1344 
1345 	pin = dev->pin;
1346 	if (!pin)
1347 		return -1;
1348 	pin--;
1349 	while (dev->bus->self) {
1350 		pin = (pin + PCI_SLOT(dev->devfn)) % 4;
1351 		dev = dev->bus->self;
1352 	}
1353 	*bridge = dev;
1354 	return pin;
1355 }
1356 
1357 /**
1358  *	pci_release_region - Release a PCI bar
1359  *	@pdev: PCI device whose resources were previously reserved by pci_request_region
1360  *	@bar: BAR to release
1361  *
1362  *	Releases the PCI I/O and memory resources previously reserved by a
1363  *	successful call to pci_request_region.  Call this function only
1364  *	after all use of the PCI regions has ceased.
1365  */
1366 void pci_release_region(struct pci_dev *pdev, int bar)
1367 {
1368 	struct pci_devres *dr;
1369 
1370 	if (pci_resource_len(pdev, bar) == 0)
1371 		return;
1372 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1373 		release_region(pci_resource_start(pdev, bar),
1374 				pci_resource_len(pdev, bar));
1375 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1376 		release_mem_region(pci_resource_start(pdev, bar),
1377 				pci_resource_len(pdev, bar));
1378 
1379 	dr = find_pci_dr(pdev);
1380 	if (dr)
1381 		dr->region_mask &= ~(1 << bar);
1382 }
1383 
1384 /**
1385  *	pci_request_region - Reserved PCI I/O and memory resource
1386  *	@pdev: PCI device whose resources are to be reserved
1387  *	@bar: BAR to be reserved
1388  *	@res_name: Name to be associated with resource.
1389  *
1390  *	Mark the PCI region associated with PCI device @pdev BR @bar as
1391  *	being reserved by owner @res_name.  Do not access any
1392  *	address inside the PCI regions unless this call returns
1393  *	successfully.
1394  *
1395  *	Returns 0 on success, or %EBUSY on error.  A warning
1396  *	message is also printed on failure.
1397  */
1398 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1399 {
1400 	struct pci_devres *dr;
1401 
1402 	if (pci_resource_len(pdev, bar) == 0)
1403 		return 0;
1404 
1405 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1406 		if (!request_region(pci_resource_start(pdev, bar),
1407 			    pci_resource_len(pdev, bar), res_name))
1408 			goto err_out;
1409 	}
1410 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1411 		if (!request_mem_region(pci_resource_start(pdev, bar),
1412 				        pci_resource_len(pdev, bar), res_name))
1413 			goto err_out;
1414 	}
1415 
1416 	dr = find_pci_dr(pdev);
1417 	if (dr)
1418 		dr->region_mask |= 1 << bar;
1419 
1420 	return 0;
1421 
1422 err_out:
1423 	dev_warn(&pdev->dev, "BAR %d: can't reserve %s region %pR\n",
1424 		 bar,
1425 		 pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
1426 		 &pdev->resource[bar]);
1427 	return -EBUSY;
1428 }
1429 
1430 /**
1431  * pci_release_selected_regions - Release selected PCI I/O and memory resources
1432  * @pdev: PCI device whose resources were previously reserved
1433  * @bars: Bitmask of BARs to be released
1434  *
1435  * Release selected PCI I/O and memory resources previously reserved.
1436  * Call this function only after all use of the PCI regions has ceased.
1437  */
1438 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1439 {
1440 	int i;
1441 
1442 	for (i = 0; i < 6; i++)
1443 		if (bars & (1 << i))
1444 			pci_release_region(pdev, i);
1445 }
1446 
1447 /**
1448  * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
1449  * @pdev: PCI device whose resources are to be reserved
1450  * @bars: Bitmask of BARs to be requested
1451  * @res_name: Name to be associated with resource
1452  */
1453 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
1454 				 const char *res_name)
1455 {
1456 	int i;
1457 
1458 	for (i = 0; i < 6; i++)
1459 		if (bars & (1 << i))
1460 			if(pci_request_region(pdev, i, res_name))
1461 				goto err_out;
1462 	return 0;
1463 
1464 err_out:
1465 	while(--i >= 0)
1466 		if (bars & (1 << i))
1467 			pci_release_region(pdev, i);
1468 
1469 	return -EBUSY;
1470 }
1471 
1472 /**
1473  *	pci_release_regions - Release reserved PCI I/O and memory resources
1474  *	@pdev: PCI device whose resources were previously reserved by pci_request_regions
1475  *
1476  *	Releases all PCI I/O and memory resources previously reserved by a
1477  *	successful call to pci_request_regions.  Call this function only
1478  *	after all use of the PCI regions has ceased.
1479  */
1480 
1481 void pci_release_regions(struct pci_dev *pdev)
1482 {
1483 	pci_release_selected_regions(pdev, (1 << 6) - 1);
1484 }
1485 
1486 /**
1487  *	pci_request_regions - Reserved PCI I/O and memory resources
1488  *	@pdev: PCI device whose resources are to be reserved
1489  *	@res_name: Name to be associated with resource.
1490  *
1491  *	Mark all PCI regions associated with PCI device @pdev as
1492  *	being reserved by owner @res_name.  Do not access any
1493  *	address inside the PCI regions unless this call returns
1494  *	successfully.
1495  *
1496  *	Returns 0 on success, or %EBUSY on error.  A warning
1497  *	message is also printed on failure.
1498  */
1499 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
1500 {
1501 	return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
1502 }
1503 
1504 /**
1505  * pci_set_master - enables bus-mastering for device dev
1506  * @dev: the PCI device to enable
1507  *
1508  * Enables bus-mastering on the device and calls pcibios_set_master()
1509  * to do the needed arch specific settings.
1510  */
1511 void
1512 pci_set_master(struct pci_dev *dev)
1513 {
1514 	u16 cmd;
1515 
1516 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1517 	if (! (cmd & PCI_COMMAND_MASTER)) {
1518 		dev_dbg(&dev->dev, "enabling bus mastering\n");
1519 		cmd |= PCI_COMMAND_MASTER;
1520 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1521 	}
1522 	dev->is_busmaster = 1;
1523 	pcibios_set_master(dev);
1524 }
1525 
1526 #ifdef PCI_DISABLE_MWI
1527 int pci_set_mwi(struct pci_dev *dev)
1528 {
1529 	return 0;
1530 }
1531 
1532 int pci_try_set_mwi(struct pci_dev *dev)
1533 {
1534 	return 0;
1535 }
1536 
1537 void pci_clear_mwi(struct pci_dev *dev)
1538 {
1539 }
1540 
1541 #else
1542 
1543 #ifndef PCI_CACHE_LINE_BYTES
1544 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
1545 #endif
1546 
1547 /* This can be overridden by arch code. */
1548 /* Don't forget this is measured in 32-bit words, not bytes */
1549 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
1550 
1551 /**
1552  * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1553  * @dev: the PCI device for which MWI is to be enabled
1554  *
1555  * Helper function for pci_set_mwi.
1556  * Originally copied from drivers/net/acenic.c.
1557  * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1558  *
1559  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1560  */
1561 static int
1562 pci_set_cacheline_size(struct pci_dev *dev)
1563 {
1564 	u8 cacheline_size;
1565 
1566 	if (!pci_cache_line_size)
1567 		return -EINVAL;		/* The system doesn't support MWI. */
1568 
1569 	/* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1570 	   equal to or multiple of the right value. */
1571 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1572 	if (cacheline_size >= pci_cache_line_size &&
1573 	    (cacheline_size % pci_cache_line_size) == 0)
1574 		return 0;
1575 
1576 	/* Write the correct value. */
1577 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1578 	/* Read it back. */
1579 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1580 	if (cacheline_size == pci_cache_line_size)
1581 		return 0;
1582 
1583 	dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
1584 		   "supported\n", pci_cache_line_size << 2);
1585 
1586 	return -EINVAL;
1587 }
1588 
1589 /**
1590  * pci_set_mwi - enables memory-write-invalidate PCI transaction
1591  * @dev: the PCI device for which MWI is enabled
1592  *
1593  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1594  *
1595  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1596  */
1597 int
1598 pci_set_mwi(struct pci_dev *dev)
1599 {
1600 	int rc;
1601 	u16 cmd;
1602 
1603 	rc = pci_set_cacheline_size(dev);
1604 	if (rc)
1605 		return rc;
1606 
1607 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1608 	if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1609 		dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
1610 		cmd |= PCI_COMMAND_INVALIDATE;
1611 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1612 	}
1613 
1614 	return 0;
1615 }
1616 
1617 /**
1618  * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
1619  * @dev: the PCI device for which MWI is enabled
1620  *
1621  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1622  * Callers are not required to check the return value.
1623  *
1624  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1625  */
1626 int pci_try_set_mwi(struct pci_dev *dev)
1627 {
1628 	int rc = pci_set_mwi(dev);
1629 	return rc;
1630 }
1631 
1632 /**
1633  * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1634  * @dev: the PCI device to disable
1635  *
1636  * Disables PCI Memory-Write-Invalidate transaction on the device
1637  */
1638 void
1639 pci_clear_mwi(struct pci_dev *dev)
1640 {
1641 	u16 cmd;
1642 
1643 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1644 	if (cmd & PCI_COMMAND_INVALIDATE) {
1645 		cmd &= ~PCI_COMMAND_INVALIDATE;
1646 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1647 	}
1648 }
1649 #endif /* ! PCI_DISABLE_MWI */
1650 
1651 /**
1652  * pci_intx - enables/disables PCI INTx for device dev
1653  * @pdev: the PCI device to operate on
1654  * @enable: boolean: whether to enable or disable PCI INTx
1655  *
1656  * Enables/disables PCI INTx for device dev
1657  */
1658 void
1659 pci_intx(struct pci_dev *pdev, int enable)
1660 {
1661 	u16 pci_command, new;
1662 
1663 	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1664 
1665 	if (enable) {
1666 		new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1667 	} else {
1668 		new = pci_command | PCI_COMMAND_INTX_DISABLE;
1669 	}
1670 
1671 	if (new != pci_command) {
1672 		struct pci_devres *dr;
1673 
1674 		pci_write_config_word(pdev, PCI_COMMAND, new);
1675 
1676 		dr = find_pci_dr(pdev);
1677 		if (dr && !dr->restore_intx) {
1678 			dr->restore_intx = 1;
1679 			dr->orig_intx = !enable;
1680 		}
1681 	}
1682 }
1683 
1684 /**
1685  * pci_msi_off - disables any msi or msix capabilities
1686  * @dev: the PCI device to operate on
1687  *
1688  * If you want to use msi see pci_enable_msi and friends.
1689  * This is a lower level primitive that allows us to disable
1690  * msi operation at the device level.
1691  */
1692 void pci_msi_off(struct pci_dev *dev)
1693 {
1694 	int pos;
1695 	u16 control;
1696 
1697 	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
1698 	if (pos) {
1699 		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
1700 		control &= ~PCI_MSI_FLAGS_ENABLE;
1701 		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
1702 	}
1703 	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1704 	if (pos) {
1705 		pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
1706 		control &= ~PCI_MSIX_FLAGS_ENABLE;
1707 		pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
1708 	}
1709 }
1710 
1711 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
1712 /*
1713  * These can be overridden by arch-specific implementations
1714  */
1715 int
1716 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
1717 {
1718 	if (!pci_dma_supported(dev, mask))
1719 		return -EIO;
1720 
1721 	dev->dma_mask = mask;
1722 
1723 	return 0;
1724 }
1725 
1726 int
1727 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
1728 {
1729 	if (!pci_dma_supported(dev, mask))
1730 		return -EIO;
1731 
1732 	dev->dev.coherent_dma_mask = mask;
1733 
1734 	return 0;
1735 }
1736 #endif
1737 
1738 #ifndef HAVE_ARCH_PCI_SET_DMA_MAX_SEGMENT_SIZE
1739 int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
1740 {
1741 	return dma_set_max_seg_size(&dev->dev, size);
1742 }
1743 EXPORT_SYMBOL(pci_set_dma_max_seg_size);
1744 #endif
1745 
1746 #ifndef HAVE_ARCH_PCI_SET_DMA_SEGMENT_BOUNDARY
1747 int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
1748 {
1749 	return dma_set_seg_boundary(&dev->dev, mask);
1750 }
1751 EXPORT_SYMBOL(pci_set_dma_seg_boundary);
1752 #endif
1753 
1754 /**
1755  * pci_execute_reset_function() - Reset a PCI device function
1756  * @dev: Device function to reset
1757  *
1758  * Some devices allow an individual function to be reset without affecting
1759  * other functions in the same device.  The PCI device must be responsive
1760  * to PCI config space in order to use this function.
1761  *
1762  * The device function is presumed to be unused when this function is called.
1763  * Resetting the device will make the contents of PCI configuration space
1764  * random, so any caller of this must be prepared to reinitialise the
1765  * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
1766  * etc.
1767  *
1768  * Returns 0 if the device function was successfully reset or -ENOTTY if the
1769  * device doesn't support resetting a single function.
1770  */
1771 int pci_execute_reset_function(struct pci_dev *dev)
1772 {
1773 	u16 status;
1774 	u32 cap;
1775 	int exppos = pci_find_capability(dev, PCI_CAP_ID_EXP);
1776 
1777 	if (!exppos)
1778 		return -ENOTTY;
1779 	pci_read_config_dword(dev, exppos + PCI_EXP_DEVCAP, &cap);
1780 	if (!(cap & PCI_EXP_DEVCAP_FLR))
1781 		return -ENOTTY;
1782 
1783 	pci_block_user_cfg_access(dev);
1784 
1785 	/* Wait for Transaction Pending bit clean */
1786 	msleep(100);
1787 	pci_read_config_word(dev, exppos + PCI_EXP_DEVSTA, &status);
1788 	if (status & PCI_EXP_DEVSTA_TRPND) {
1789 		dev_info(&dev->dev, "Busy after 100ms while trying to reset; "
1790 			"sleeping for 1 second\n");
1791 		ssleep(1);
1792 		pci_read_config_word(dev, exppos + PCI_EXP_DEVSTA, &status);
1793 		if (status & PCI_EXP_DEVSTA_TRPND)
1794 			dev_info(&dev->dev, "Still busy after 1s; "
1795 				"proceeding with reset anyway\n");
1796 	}
1797 
1798 	pci_write_config_word(dev, exppos + PCI_EXP_DEVCTL,
1799 				PCI_EXP_DEVCTL_BCR_FLR);
1800 	mdelay(100);
1801 
1802 	pci_unblock_user_cfg_access(dev);
1803 	return 0;
1804 }
1805 EXPORT_SYMBOL_GPL(pci_execute_reset_function);
1806 
1807 /**
1808  * pci_reset_function() - quiesce and reset a PCI device function
1809  * @dev: Device function to reset
1810  *
1811  * Some devices allow an individual function to be reset without affecting
1812  * other functions in the same device.  The PCI device must be responsive
1813  * to PCI config space in order to use this function.
1814  *
1815  * This function does not just reset the PCI portion of a device, but
1816  * clears all the state associated with the device.  This function differs
1817  * from pci_execute_reset_function in that it saves and restores device state
1818  * over the reset.
1819  *
1820  * Returns 0 if the device function was successfully reset or -ENOTTY if the
1821  * device doesn't support resetting a single function.
1822  */
1823 int pci_reset_function(struct pci_dev *dev)
1824 {
1825 	u32 cap;
1826 	int exppos = pci_find_capability(dev, PCI_CAP_ID_EXP);
1827 	int r;
1828 
1829 	if (!exppos)
1830 		return -ENOTTY;
1831 	pci_read_config_dword(dev, exppos + PCI_EXP_DEVCAP, &cap);
1832 	if (!(cap & PCI_EXP_DEVCAP_FLR))
1833 		return -ENOTTY;
1834 
1835 	if (!dev->msi_enabled && !dev->msix_enabled)
1836 		disable_irq(dev->irq);
1837 	pci_save_state(dev);
1838 
1839 	pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
1840 
1841 	r = pci_execute_reset_function(dev);
1842 
1843 	pci_restore_state(dev);
1844 	if (!dev->msi_enabled && !dev->msix_enabled)
1845 		enable_irq(dev->irq);
1846 
1847 	return r;
1848 }
1849 EXPORT_SYMBOL_GPL(pci_reset_function);
1850 
1851 /**
1852  * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
1853  * @dev: PCI device to query
1854  *
1855  * Returns mmrbc: maximum designed memory read count in bytes
1856  *    or appropriate error value.
1857  */
1858 int pcix_get_max_mmrbc(struct pci_dev *dev)
1859 {
1860 	int err, cap;
1861 	u32 stat;
1862 
1863 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1864 	if (!cap)
1865 		return -EINVAL;
1866 
1867 	err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
1868 	if (err)
1869 		return -EINVAL;
1870 
1871 	return (stat & PCI_X_STATUS_MAX_READ) >> 12;
1872 }
1873 EXPORT_SYMBOL(pcix_get_max_mmrbc);
1874 
1875 /**
1876  * pcix_get_mmrbc - get PCI-X maximum memory read byte count
1877  * @dev: PCI device to query
1878  *
1879  * Returns mmrbc: maximum memory read count in bytes
1880  *    or appropriate error value.
1881  */
1882 int pcix_get_mmrbc(struct pci_dev *dev)
1883 {
1884 	int ret, cap;
1885 	u32 cmd;
1886 
1887 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1888 	if (!cap)
1889 		return -EINVAL;
1890 
1891 	ret = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
1892 	if (!ret)
1893 		ret = 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
1894 
1895 	return ret;
1896 }
1897 EXPORT_SYMBOL(pcix_get_mmrbc);
1898 
1899 /**
1900  * pcix_set_mmrbc - set PCI-X maximum memory read byte count
1901  * @dev: PCI device to query
1902  * @mmrbc: maximum memory read count in bytes
1903  *    valid values are 512, 1024, 2048, 4096
1904  *
1905  * If possible sets maximum memory read byte count, some bridges have erratas
1906  * that prevent this.
1907  */
1908 int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
1909 {
1910 	int cap, err = -EINVAL;
1911 	u32 stat, cmd, v, o;
1912 
1913 	if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
1914 		goto out;
1915 
1916 	v = ffs(mmrbc) - 10;
1917 
1918 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1919 	if (!cap)
1920 		goto out;
1921 
1922 	err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
1923 	if (err)
1924 		goto out;
1925 
1926 	if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
1927 		return -E2BIG;
1928 
1929 	err = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
1930 	if (err)
1931 		goto out;
1932 
1933 	o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
1934 	if (o != v) {
1935 		if (v > o && dev->bus &&
1936 		   (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
1937 			return -EIO;
1938 
1939 		cmd &= ~PCI_X_CMD_MAX_READ;
1940 		cmd |= v << 2;
1941 		err = pci_write_config_dword(dev, cap + PCI_X_CMD, cmd);
1942 	}
1943 out:
1944 	return err;
1945 }
1946 EXPORT_SYMBOL(pcix_set_mmrbc);
1947 
1948 /**
1949  * pcie_get_readrq - get PCI Express read request size
1950  * @dev: PCI device to query
1951  *
1952  * Returns maximum memory read request in bytes
1953  *    or appropriate error value.
1954  */
1955 int pcie_get_readrq(struct pci_dev *dev)
1956 {
1957 	int ret, cap;
1958 	u16 ctl;
1959 
1960 	cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
1961 	if (!cap)
1962 		return -EINVAL;
1963 
1964 	ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
1965 	if (!ret)
1966 	ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
1967 
1968 	return ret;
1969 }
1970 EXPORT_SYMBOL(pcie_get_readrq);
1971 
1972 /**
1973  * pcie_set_readrq - set PCI Express maximum memory read request
1974  * @dev: PCI device to query
1975  * @rq: maximum memory read count in bytes
1976  *    valid values are 128, 256, 512, 1024, 2048, 4096
1977  *
1978  * If possible sets maximum read byte count
1979  */
1980 int pcie_set_readrq(struct pci_dev *dev, int rq)
1981 {
1982 	int cap, err = -EINVAL;
1983 	u16 ctl, v;
1984 
1985 	if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
1986 		goto out;
1987 
1988 	v = (ffs(rq) - 8) << 12;
1989 
1990 	cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
1991 	if (!cap)
1992 		goto out;
1993 
1994 	err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
1995 	if (err)
1996 		goto out;
1997 
1998 	if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
1999 		ctl &= ~PCI_EXP_DEVCTL_READRQ;
2000 		ctl |= v;
2001 		err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
2002 	}
2003 
2004 out:
2005 	return err;
2006 }
2007 EXPORT_SYMBOL(pcie_set_readrq);
2008 
2009 /**
2010  * pci_select_bars - Make BAR mask from the type of resource
2011  * @dev: the PCI device for which BAR mask is made
2012  * @flags: resource type mask to be selected
2013  *
2014  * This helper routine makes bar mask from the type of resource.
2015  */
2016 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
2017 {
2018 	int i, bars = 0;
2019 	for (i = 0; i < PCI_NUM_RESOURCES; i++)
2020 		if (pci_resource_flags(dev, i) & flags)
2021 			bars |= (1 << i);
2022 	return bars;
2023 }
2024 
2025 static void __devinit pci_no_domains(void)
2026 {
2027 #ifdef CONFIG_PCI_DOMAINS
2028 	pci_domains_supported = 0;
2029 #endif
2030 }
2031 
2032 static int __devinit pci_init(void)
2033 {
2034 	struct pci_dev *dev = NULL;
2035 
2036 	while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
2037 		pci_fixup_device(pci_fixup_final, dev);
2038 	}
2039 
2040 	msi_init();
2041 
2042 	return 0;
2043 }
2044 
2045 static int __devinit pci_setup(char *str)
2046 {
2047 	while (str) {
2048 		char *k = strchr(str, ',');
2049 		if (k)
2050 			*k++ = 0;
2051 		if (*str && (str = pcibios_setup(str)) && *str) {
2052 			if (!strcmp(str, "nomsi")) {
2053 				pci_no_msi();
2054 			} else if (!strcmp(str, "noaer")) {
2055 				pci_no_aer();
2056 			} else if (!strcmp(str, "nodomains")) {
2057 				pci_no_domains();
2058 			} else if (!strncmp(str, "cbiosize=", 9)) {
2059 				pci_cardbus_io_size = memparse(str + 9, &str);
2060 			} else if (!strncmp(str, "cbmemsize=", 10)) {
2061 				pci_cardbus_mem_size = memparse(str + 10, &str);
2062 			} else {
2063 				printk(KERN_ERR "PCI: Unknown option `%s'\n",
2064 						str);
2065 			}
2066 		}
2067 		str = k;
2068 	}
2069 	return 0;
2070 }
2071 early_param("pci", pci_setup);
2072 
2073 device_initcall(pci_init);
2074 
2075 EXPORT_SYMBOL(pci_reenable_device);
2076 EXPORT_SYMBOL(pci_enable_device_io);
2077 EXPORT_SYMBOL(pci_enable_device_mem);
2078 EXPORT_SYMBOL(pci_enable_device);
2079 EXPORT_SYMBOL(pcim_enable_device);
2080 EXPORT_SYMBOL(pcim_pin_device);
2081 EXPORT_SYMBOL(pci_disable_device);
2082 EXPORT_SYMBOL(pci_find_capability);
2083 EXPORT_SYMBOL(pci_bus_find_capability);
2084 EXPORT_SYMBOL(pci_release_regions);
2085 EXPORT_SYMBOL(pci_request_regions);
2086 EXPORT_SYMBOL(pci_release_region);
2087 EXPORT_SYMBOL(pci_request_region);
2088 EXPORT_SYMBOL(pci_release_selected_regions);
2089 EXPORT_SYMBOL(pci_request_selected_regions);
2090 EXPORT_SYMBOL(pci_set_master);
2091 EXPORT_SYMBOL(pci_set_mwi);
2092 EXPORT_SYMBOL(pci_try_set_mwi);
2093 EXPORT_SYMBOL(pci_clear_mwi);
2094 EXPORT_SYMBOL_GPL(pci_intx);
2095 EXPORT_SYMBOL(pci_set_dma_mask);
2096 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
2097 EXPORT_SYMBOL(pci_assign_resource);
2098 EXPORT_SYMBOL(pci_find_parent_resource);
2099 EXPORT_SYMBOL(pci_select_bars);
2100 
2101 EXPORT_SYMBOL(pci_set_power_state);
2102 EXPORT_SYMBOL(pci_save_state);
2103 EXPORT_SYMBOL(pci_restore_state);
2104 EXPORT_SYMBOL(pci_pme_capable);
2105 EXPORT_SYMBOL(pci_pme_active);
2106 EXPORT_SYMBOL(pci_enable_wake);
2107 EXPORT_SYMBOL(pci_wake_from_d3);
2108 EXPORT_SYMBOL(pci_target_state);
2109 EXPORT_SYMBOL(pci_prepare_to_sleep);
2110 EXPORT_SYMBOL(pci_back_from_sleep);
2111 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
2112 
2113