xref: /linux/drivers/pci/pci.c (revision 273b281fa22c293963ee3e6eec418f5dda2dbc83)
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 #define DEFAULT_HOTPLUG_IO_SIZE		(256)
45 #define DEFAULT_HOTPLUG_MEM_SIZE	(2*1024*1024)
46 /* pci=hpmemsize=nnM,hpiosize=nn can override this */
47 unsigned long pci_hotplug_io_size  = DEFAULT_HOTPLUG_IO_SIZE;
48 unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
49 
50 /*
51  * The default CLS is used if arch didn't set CLS explicitly and not
52  * all pci devices agree on the same value.  Arch can override either
53  * the dfl or actual value as it sees fit.  Don't forget this is
54  * measured in 32-bit words, not bytes.
55  */
56 u8 pci_dfl_cache_line_size __devinitdata = L1_CACHE_BYTES >> 2;
57 u8 pci_cache_line_size;
58 
59 /**
60  * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
61  * @bus: pointer to PCI bus structure to search
62  *
63  * Given a PCI bus, returns the highest PCI bus number present in the set
64  * including the given PCI bus and its list of child PCI buses.
65  */
66 unsigned char pci_bus_max_busnr(struct pci_bus* bus)
67 {
68 	struct list_head *tmp;
69 	unsigned char max, n;
70 
71 	max = bus->subordinate;
72 	list_for_each(tmp, &bus->children) {
73 		n = pci_bus_max_busnr(pci_bus_b(tmp));
74 		if(n > max)
75 			max = n;
76 	}
77 	return max;
78 }
79 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
80 
81 #ifdef CONFIG_HAS_IOMEM
82 void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
83 {
84 	/*
85 	 * Make sure the BAR is actually a memory resource, not an IO resource
86 	 */
87 	if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
88 		WARN_ON(1);
89 		return NULL;
90 	}
91 	return ioremap_nocache(pci_resource_start(pdev, bar),
92 				     pci_resource_len(pdev, bar));
93 }
94 EXPORT_SYMBOL_GPL(pci_ioremap_bar);
95 #endif
96 
97 #if 0
98 /**
99  * pci_max_busnr - returns maximum PCI bus number
100  *
101  * Returns the highest PCI bus number present in the system global list of
102  * PCI buses.
103  */
104 unsigned char __devinit
105 pci_max_busnr(void)
106 {
107 	struct pci_bus *bus = NULL;
108 	unsigned char max, n;
109 
110 	max = 0;
111 	while ((bus = pci_find_next_bus(bus)) != NULL) {
112 		n = pci_bus_max_busnr(bus);
113 		if(n > max)
114 			max = n;
115 	}
116 	return max;
117 }
118 
119 #endif  /*  0  */
120 
121 #define PCI_FIND_CAP_TTL	48
122 
123 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
124 				   u8 pos, int cap, int *ttl)
125 {
126 	u8 id;
127 
128 	while ((*ttl)--) {
129 		pci_bus_read_config_byte(bus, devfn, pos, &pos);
130 		if (pos < 0x40)
131 			break;
132 		pos &= ~3;
133 		pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
134 					 &id);
135 		if (id == 0xff)
136 			break;
137 		if (id == cap)
138 			return pos;
139 		pos += PCI_CAP_LIST_NEXT;
140 	}
141 	return 0;
142 }
143 
144 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
145 			       u8 pos, int cap)
146 {
147 	int ttl = PCI_FIND_CAP_TTL;
148 
149 	return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
150 }
151 
152 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
153 {
154 	return __pci_find_next_cap(dev->bus, dev->devfn,
155 				   pos + PCI_CAP_LIST_NEXT, cap);
156 }
157 EXPORT_SYMBOL_GPL(pci_find_next_capability);
158 
159 static int __pci_bus_find_cap_start(struct pci_bus *bus,
160 				    unsigned int devfn, u8 hdr_type)
161 {
162 	u16 status;
163 
164 	pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
165 	if (!(status & PCI_STATUS_CAP_LIST))
166 		return 0;
167 
168 	switch (hdr_type) {
169 	case PCI_HEADER_TYPE_NORMAL:
170 	case PCI_HEADER_TYPE_BRIDGE:
171 		return PCI_CAPABILITY_LIST;
172 	case PCI_HEADER_TYPE_CARDBUS:
173 		return PCI_CB_CAPABILITY_LIST;
174 	default:
175 		return 0;
176 	}
177 
178 	return 0;
179 }
180 
181 /**
182  * pci_find_capability - query for devices' capabilities
183  * @dev: PCI device to query
184  * @cap: capability code
185  *
186  * Tell if a device supports a given PCI capability.
187  * Returns the address of the requested capability structure within the
188  * device's PCI configuration space or 0 in case the device does not
189  * support it.  Possible values for @cap:
190  *
191  *  %PCI_CAP_ID_PM           Power Management
192  *  %PCI_CAP_ID_AGP          Accelerated Graphics Port
193  *  %PCI_CAP_ID_VPD          Vital Product Data
194  *  %PCI_CAP_ID_SLOTID       Slot Identification
195  *  %PCI_CAP_ID_MSI          Message Signalled Interrupts
196  *  %PCI_CAP_ID_CHSWP        CompactPCI HotSwap
197  *  %PCI_CAP_ID_PCIX         PCI-X
198  *  %PCI_CAP_ID_EXP          PCI Express
199  */
200 int pci_find_capability(struct pci_dev *dev, int cap)
201 {
202 	int pos;
203 
204 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
205 	if (pos)
206 		pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
207 
208 	return pos;
209 }
210 
211 /**
212  * pci_bus_find_capability - query for devices' capabilities
213  * @bus:   the PCI bus to query
214  * @devfn: PCI device to query
215  * @cap:   capability code
216  *
217  * Like pci_find_capability() but works for pci devices that do not have a
218  * pci_dev structure set up yet.
219  *
220  * Returns the address of the requested capability structure within the
221  * device's PCI configuration space or 0 in case the device does not
222  * support it.
223  */
224 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
225 {
226 	int pos;
227 	u8 hdr_type;
228 
229 	pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
230 
231 	pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
232 	if (pos)
233 		pos = __pci_find_next_cap(bus, devfn, pos, cap);
234 
235 	return pos;
236 }
237 
238 /**
239  * pci_find_ext_capability - Find an extended capability
240  * @dev: PCI device to query
241  * @cap: capability code
242  *
243  * Returns the address of the requested extended capability structure
244  * within the device's PCI configuration space or 0 if the device does
245  * not support it.  Possible values for @cap:
246  *
247  *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
248  *  %PCI_EXT_CAP_ID_VC		Virtual Channel
249  *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
250  *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
251  */
252 int pci_find_ext_capability(struct pci_dev *dev, int cap)
253 {
254 	u32 header;
255 	int ttl;
256 	int pos = PCI_CFG_SPACE_SIZE;
257 
258 	/* minimum 8 bytes per capability */
259 	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
260 
261 	if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
262 		return 0;
263 
264 	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
265 		return 0;
266 
267 	/*
268 	 * If we have no capabilities, this is indicated by cap ID,
269 	 * cap version and next pointer all being 0.
270 	 */
271 	if (header == 0)
272 		return 0;
273 
274 	while (ttl-- > 0) {
275 		if (PCI_EXT_CAP_ID(header) == cap)
276 			return pos;
277 
278 		pos = PCI_EXT_CAP_NEXT(header);
279 		if (pos < PCI_CFG_SPACE_SIZE)
280 			break;
281 
282 		if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
283 			break;
284 	}
285 
286 	return 0;
287 }
288 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
289 
290 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
291 {
292 	int rc, ttl = PCI_FIND_CAP_TTL;
293 	u8 cap, mask;
294 
295 	if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
296 		mask = HT_3BIT_CAP_MASK;
297 	else
298 		mask = HT_5BIT_CAP_MASK;
299 
300 	pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
301 				      PCI_CAP_ID_HT, &ttl);
302 	while (pos) {
303 		rc = pci_read_config_byte(dev, pos + 3, &cap);
304 		if (rc != PCIBIOS_SUCCESSFUL)
305 			return 0;
306 
307 		if ((cap & mask) == ht_cap)
308 			return pos;
309 
310 		pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
311 					      pos + PCI_CAP_LIST_NEXT,
312 					      PCI_CAP_ID_HT, &ttl);
313 	}
314 
315 	return 0;
316 }
317 /**
318  * pci_find_next_ht_capability - query a device's Hypertransport capabilities
319  * @dev: PCI device to query
320  * @pos: Position from which to continue searching
321  * @ht_cap: Hypertransport capability code
322  *
323  * To be used in conjunction with pci_find_ht_capability() to search for
324  * all capabilities matching @ht_cap. @pos should always be a value returned
325  * from pci_find_ht_capability().
326  *
327  * NB. To be 100% safe against broken PCI devices, the caller should take
328  * steps to avoid an infinite loop.
329  */
330 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
331 {
332 	return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
333 }
334 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
335 
336 /**
337  * pci_find_ht_capability - query a device's Hypertransport capabilities
338  * @dev: PCI device to query
339  * @ht_cap: Hypertransport capability code
340  *
341  * Tell if a device supports a given Hypertransport capability.
342  * Returns an address within the device's PCI configuration space
343  * or 0 in case the device does not support the request capability.
344  * The address points to the PCI capability, of type PCI_CAP_ID_HT,
345  * which has a Hypertransport capability matching @ht_cap.
346  */
347 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
348 {
349 	int pos;
350 
351 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
352 	if (pos)
353 		pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
354 
355 	return pos;
356 }
357 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
358 
359 /**
360  * pci_find_parent_resource - return resource region of parent bus of given region
361  * @dev: PCI device structure contains resources to be searched
362  * @res: child resource record for which parent is sought
363  *
364  *  For given resource region of given device, return the resource
365  *  region of parent bus the given region is contained in or where
366  *  it should be allocated from.
367  */
368 struct resource *
369 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
370 {
371 	const struct pci_bus *bus = dev->bus;
372 	int i;
373 	struct resource *best = NULL;
374 
375 	for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
376 		struct resource *r = bus->resource[i];
377 		if (!r)
378 			continue;
379 		if (res->start && !(res->start >= r->start && res->end <= r->end))
380 			continue;	/* Not contained */
381 		if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
382 			continue;	/* Wrong type */
383 		if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
384 			return r;	/* Exact match */
385 		/* We can't insert a non-prefetch resource inside a prefetchable parent .. */
386 		if (r->flags & IORESOURCE_PREFETCH)
387 			continue;
388 		/* .. but we can put a prefetchable resource inside a non-prefetchable one */
389 		if (!best)
390 			best = r;
391 	}
392 	return best;
393 }
394 
395 /**
396  * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
397  * @dev: PCI device to have its BARs restored
398  *
399  * Restore the BAR values for a given device, so as to make it
400  * accessible by its driver.
401  */
402 static void
403 pci_restore_bars(struct pci_dev *dev)
404 {
405 	int i;
406 
407 	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
408 		pci_update_resource(dev, i);
409 }
410 
411 static struct pci_platform_pm_ops *pci_platform_pm;
412 
413 int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
414 {
415 	if (!ops->is_manageable || !ops->set_state || !ops->choose_state
416 	    || !ops->sleep_wake || !ops->can_wakeup)
417 		return -EINVAL;
418 	pci_platform_pm = ops;
419 	return 0;
420 }
421 
422 static inline bool platform_pci_power_manageable(struct pci_dev *dev)
423 {
424 	return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
425 }
426 
427 static inline int platform_pci_set_power_state(struct pci_dev *dev,
428                                                 pci_power_t t)
429 {
430 	return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
431 }
432 
433 static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
434 {
435 	return pci_platform_pm ?
436 			pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
437 }
438 
439 static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
440 {
441 	return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
442 }
443 
444 static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
445 {
446 	return pci_platform_pm ?
447 			pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
448 }
449 
450 /**
451  * pci_raw_set_power_state - Use PCI PM registers to set the power state of
452  *                           given PCI device
453  * @dev: PCI device to handle.
454  * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
455  *
456  * RETURN VALUE:
457  * -EINVAL if the requested state is invalid.
458  * -EIO if device does not support PCI PM or its PM capabilities register has a
459  * wrong version, or device doesn't support the requested state.
460  * 0 if device already is in the requested state.
461  * 0 if device's power state has been successfully changed.
462  */
463 static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
464 {
465 	u16 pmcsr;
466 	bool need_restore = false;
467 
468 	/* Check if we're already there */
469 	if (dev->current_state == state)
470 		return 0;
471 
472 	if (!dev->pm_cap)
473 		return -EIO;
474 
475 	if (state < PCI_D0 || state > PCI_D3hot)
476 		return -EINVAL;
477 
478 	/* Validate current state:
479 	 * Can enter D0 from any state, but if we can only go deeper
480 	 * to sleep if we're already in a low power state
481 	 */
482 	if (state != PCI_D0 && dev->current_state <= PCI_D3cold
483 	    && dev->current_state > state) {
484 		dev_err(&dev->dev, "invalid power transition "
485 			"(from state %d to %d)\n", dev->current_state, state);
486 		return -EINVAL;
487 	}
488 
489 	/* check if this device supports the desired state */
490 	if ((state == PCI_D1 && !dev->d1_support)
491 	   || (state == PCI_D2 && !dev->d2_support))
492 		return -EIO;
493 
494 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
495 
496 	/* If we're (effectively) in D3, force entire word to 0.
497 	 * This doesn't affect PME_Status, disables PME_En, and
498 	 * sets PowerState to 0.
499 	 */
500 	switch (dev->current_state) {
501 	case PCI_D0:
502 	case PCI_D1:
503 	case PCI_D2:
504 		pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
505 		pmcsr |= state;
506 		break;
507 	case PCI_D3hot:
508 	case PCI_D3cold:
509 	case PCI_UNKNOWN: /* Boot-up */
510 		if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
511 		 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
512 			need_restore = true;
513 		/* Fall-through: force to D0 */
514 	default:
515 		pmcsr = 0;
516 		break;
517 	}
518 
519 	/* enter specified state */
520 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
521 
522 	/* Mandatory power management transition delays */
523 	/* see PCI PM 1.1 5.6.1 table 18 */
524 	if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
525 		msleep(pci_pm_d3_delay);
526 	else if (state == PCI_D2 || dev->current_state == PCI_D2)
527 		udelay(PCI_PM_D2_DELAY);
528 
529 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
530 	dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
531 	if (dev->current_state != state && printk_ratelimit())
532 		dev_info(&dev->dev, "Refused to change power state, "
533 			"currently in D%d\n", dev->current_state);
534 
535 	/* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
536 	 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
537 	 * from D3hot to D0 _may_ perform an internal reset, thereby
538 	 * going to "D0 Uninitialized" rather than "D0 Initialized".
539 	 * For example, at least some versions of the 3c905B and the
540 	 * 3c556B exhibit this behaviour.
541 	 *
542 	 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
543 	 * devices in a D3hot state at boot.  Consequently, we need to
544 	 * restore at least the BARs so that the device will be
545 	 * accessible to its driver.
546 	 */
547 	if (need_restore)
548 		pci_restore_bars(dev);
549 
550 	if (dev->bus->self)
551 		pcie_aspm_pm_state_change(dev->bus->self);
552 
553 	return 0;
554 }
555 
556 /**
557  * pci_update_current_state - Read PCI power state of given device from its
558  *                            PCI PM registers and cache it
559  * @dev: PCI device to handle.
560  * @state: State to cache in case the device doesn't have the PM capability
561  */
562 void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
563 {
564 	if (dev->pm_cap) {
565 		u16 pmcsr;
566 
567 		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
568 		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
569 	} else {
570 		dev->current_state = state;
571 	}
572 }
573 
574 /**
575  * pci_platform_power_transition - Use platform to change device power state
576  * @dev: PCI device to handle.
577  * @state: State to put the device into.
578  */
579 static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
580 {
581 	int error;
582 
583 	if (platform_pci_power_manageable(dev)) {
584 		error = platform_pci_set_power_state(dev, state);
585 		if (!error)
586 			pci_update_current_state(dev, state);
587 	} else {
588 		error = -ENODEV;
589 		/* Fall back to PCI_D0 if native PM is not supported */
590 		if (!dev->pm_cap)
591 			dev->current_state = PCI_D0;
592 	}
593 
594 	return error;
595 }
596 
597 /**
598  * __pci_start_power_transition - Start power transition of a PCI device
599  * @dev: PCI device to handle.
600  * @state: State to put the device into.
601  */
602 static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
603 {
604 	if (state == PCI_D0)
605 		pci_platform_power_transition(dev, PCI_D0);
606 }
607 
608 /**
609  * __pci_complete_power_transition - Complete power transition of a PCI device
610  * @dev: PCI device to handle.
611  * @state: State to put the device into.
612  *
613  * This function should not be called directly by device drivers.
614  */
615 int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
616 {
617 	return state > PCI_D0 ?
618 			pci_platform_power_transition(dev, state) : -EINVAL;
619 }
620 EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
621 
622 /**
623  * pci_set_power_state - Set the power state of a PCI device
624  * @dev: PCI device to handle.
625  * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
626  *
627  * Transition a device to a new power state, using the platform firmware and/or
628  * the device's PCI PM registers.
629  *
630  * RETURN VALUE:
631  * -EINVAL if the requested state is invalid.
632  * -EIO if device does not support PCI PM or its PM capabilities register has a
633  * wrong version, or device doesn't support the requested state.
634  * 0 if device already is in the requested state.
635  * 0 if device's power state has been successfully changed.
636  */
637 int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
638 {
639 	int error;
640 
641 	/* bound the state we're entering */
642 	if (state > PCI_D3hot)
643 		state = PCI_D3hot;
644 	else if (state < PCI_D0)
645 		state = PCI_D0;
646 	else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
647 		/*
648 		 * If the device or the parent bridge do not support PCI PM,
649 		 * ignore the request if we're doing anything other than putting
650 		 * it into D0 (which would only happen on boot).
651 		 */
652 		return 0;
653 
654 	/* Check if we're already there */
655 	if (dev->current_state == state)
656 		return 0;
657 
658 	__pci_start_power_transition(dev, state);
659 
660 	/* This device is quirked not to be put into D3, so
661 	   don't put it in D3 */
662 	if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
663 		return 0;
664 
665 	error = pci_raw_set_power_state(dev, state);
666 
667 	if (!__pci_complete_power_transition(dev, state))
668 		error = 0;
669 
670 	return error;
671 }
672 
673 /**
674  * pci_choose_state - Choose the power state of a PCI device
675  * @dev: PCI device to be suspended
676  * @state: target sleep state for the whole system. This is the value
677  *	that is passed to suspend() function.
678  *
679  * Returns PCI power state suitable for given device and given system
680  * message.
681  */
682 
683 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
684 {
685 	pci_power_t ret;
686 
687 	if (!pci_find_capability(dev, PCI_CAP_ID_PM))
688 		return PCI_D0;
689 
690 	ret = platform_pci_choose_state(dev);
691 	if (ret != PCI_POWER_ERROR)
692 		return ret;
693 
694 	switch (state.event) {
695 	case PM_EVENT_ON:
696 		return PCI_D0;
697 	case PM_EVENT_FREEZE:
698 	case PM_EVENT_PRETHAW:
699 		/* REVISIT both freeze and pre-thaw "should" use D0 */
700 	case PM_EVENT_SUSPEND:
701 	case PM_EVENT_HIBERNATE:
702 		return PCI_D3hot;
703 	default:
704 		dev_info(&dev->dev, "unrecognized suspend event %d\n",
705 			 state.event);
706 		BUG();
707 	}
708 	return PCI_D0;
709 }
710 
711 EXPORT_SYMBOL(pci_choose_state);
712 
713 #define PCI_EXP_SAVE_REGS	7
714 
715 #define pcie_cap_has_devctl(type, flags)	1
716 #define pcie_cap_has_lnkctl(type, flags)		\
717 		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
718 		 (type == PCI_EXP_TYPE_ROOT_PORT ||	\
719 		  type == PCI_EXP_TYPE_ENDPOINT ||	\
720 		  type == PCI_EXP_TYPE_LEG_END))
721 #define pcie_cap_has_sltctl(type, flags)		\
722 		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
723 		 ((type == PCI_EXP_TYPE_ROOT_PORT) ||	\
724 		  (type == PCI_EXP_TYPE_DOWNSTREAM &&	\
725 		   (flags & PCI_EXP_FLAGS_SLOT))))
726 #define pcie_cap_has_rtctl(type, flags)			\
727 		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
728 		 (type == PCI_EXP_TYPE_ROOT_PORT ||	\
729 		  type == PCI_EXP_TYPE_RC_EC))
730 #define pcie_cap_has_devctl2(type, flags)		\
731 		((flags & PCI_EXP_FLAGS_VERS) > 1)
732 #define pcie_cap_has_lnkctl2(type, flags)		\
733 		((flags & PCI_EXP_FLAGS_VERS) > 1)
734 #define pcie_cap_has_sltctl2(type, flags)		\
735 		((flags & PCI_EXP_FLAGS_VERS) > 1)
736 
737 static int pci_save_pcie_state(struct pci_dev *dev)
738 {
739 	int pos, i = 0;
740 	struct pci_cap_saved_state *save_state;
741 	u16 *cap;
742 	u16 flags;
743 
744 	pos = pci_pcie_cap(dev);
745 	if (!pos)
746 		return 0;
747 
748 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
749 	if (!save_state) {
750 		dev_err(&dev->dev, "buffer not found in %s\n", __func__);
751 		return -ENOMEM;
752 	}
753 	cap = (u16 *)&save_state->data[0];
754 
755 	pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
756 
757 	if (pcie_cap_has_devctl(dev->pcie_type, flags))
758 		pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
759 	if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
760 		pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
761 	if (pcie_cap_has_sltctl(dev->pcie_type, flags))
762 		pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
763 	if (pcie_cap_has_rtctl(dev->pcie_type, flags))
764 		pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
765 	if (pcie_cap_has_devctl2(dev->pcie_type, flags))
766 		pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &cap[i++]);
767 	if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
768 		pci_read_config_word(dev, pos + PCI_EXP_LNKCTL2, &cap[i++]);
769 	if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
770 		pci_read_config_word(dev, pos + PCI_EXP_SLTCTL2, &cap[i++]);
771 
772 	return 0;
773 }
774 
775 static void pci_restore_pcie_state(struct pci_dev *dev)
776 {
777 	int i = 0, pos;
778 	struct pci_cap_saved_state *save_state;
779 	u16 *cap;
780 	u16 flags;
781 
782 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
783 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
784 	if (!save_state || pos <= 0)
785 		return;
786 	cap = (u16 *)&save_state->data[0];
787 
788 	pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
789 
790 	if (pcie_cap_has_devctl(dev->pcie_type, flags))
791 		pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
792 	if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
793 		pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
794 	if (pcie_cap_has_sltctl(dev->pcie_type, flags))
795 		pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
796 	if (pcie_cap_has_rtctl(dev->pcie_type, flags))
797 		pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
798 	if (pcie_cap_has_devctl2(dev->pcie_type, flags))
799 		pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, cap[i++]);
800 	if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
801 		pci_write_config_word(dev, pos + PCI_EXP_LNKCTL2, cap[i++]);
802 	if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
803 		pci_write_config_word(dev, pos + PCI_EXP_SLTCTL2, cap[i++]);
804 }
805 
806 
807 static int pci_save_pcix_state(struct pci_dev *dev)
808 {
809 	int pos;
810 	struct pci_cap_saved_state *save_state;
811 
812 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
813 	if (pos <= 0)
814 		return 0;
815 
816 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
817 	if (!save_state) {
818 		dev_err(&dev->dev, "buffer not found in %s\n", __func__);
819 		return -ENOMEM;
820 	}
821 
822 	pci_read_config_word(dev, pos + PCI_X_CMD, (u16 *)save_state->data);
823 
824 	return 0;
825 }
826 
827 static void pci_restore_pcix_state(struct pci_dev *dev)
828 {
829 	int i = 0, pos;
830 	struct pci_cap_saved_state *save_state;
831 	u16 *cap;
832 
833 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
834 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
835 	if (!save_state || pos <= 0)
836 		return;
837 	cap = (u16 *)&save_state->data[0];
838 
839 	pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
840 }
841 
842 
843 /**
844  * pci_save_state - save the PCI configuration space of a device before suspending
845  * @dev: - PCI device that we're dealing with
846  */
847 int
848 pci_save_state(struct pci_dev *dev)
849 {
850 	int i;
851 	/* XXX: 100% dword access ok here? */
852 	for (i = 0; i < 16; i++)
853 		pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
854 	dev->state_saved = true;
855 	if ((i = pci_save_pcie_state(dev)) != 0)
856 		return i;
857 	if ((i = pci_save_pcix_state(dev)) != 0)
858 		return i;
859 	return 0;
860 }
861 
862 /**
863  * pci_restore_state - Restore the saved state of a PCI device
864  * @dev: - PCI device that we're dealing with
865  */
866 int
867 pci_restore_state(struct pci_dev *dev)
868 {
869 	int i;
870 	u32 val;
871 
872 	if (!dev->state_saved)
873 		return 0;
874 
875 	/* PCI Express register must be restored first */
876 	pci_restore_pcie_state(dev);
877 
878 	/*
879 	 * The Base Address register should be programmed before the command
880 	 * register(s)
881 	 */
882 	for (i = 15; i >= 0; i--) {
883 		pci_read_config_dword(dev, i * 4, &val);
884 		if (val != dev->saved_config_space[i]) {
885 			dev_printk(KERN_DEBUG, &dev->dev, "restoring config "
886 				"space at offset %#x (was %#x, writing %#x)\n",
887 				i, val, (int)dev->saved_config_space[i]);
888 			pci_write_config_dword(dev,i * 4,
889 				dev->saved_config_space[i]);
890 		}
891 	}
892 	pci_restore_pcix_state(dev);
893 	pci_restore_msi_state(dev);
894 	pci_restore_iov_state(dev);
895 
896 	dev->state_saved = false;
897 
898 	return 0;
899 }
900 
901 static int do_pci_enable_device(struct pci_dev *dev, int bars)
902 {
903 	int err;
904 
905 	err = pci_set_power_state(dev, PCI_D0);
906 	if (err < 0 && err != -EIO)
907 		return err;
908 	err = pcibios_enable_device(dev, bars);
909 	if (err < 0)
910 		return err;
911 	pci_fixup_device(pci_fixup_enable, dev);
912 
913 	return 0;
914 }
915 
916 /**
917  * pci_reenable_device - Resume abandoned device
918  * @dev: PCI device to be resumed
919  *
920  *  Note this function is a backend of pci_default_resume and is not supposed
921  *  to be called by normal code, write proper resume handler and use it instead.
922  */
923 int pci_reenable_device(struct pci_dev *dev)
924 {
925 	if (pci_is_enabled(dev))
926 		return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
927 	return 0;
928 }
929 
930 static int __pci_enable_device_flags(struct pci_dev *dev,
931 				     resource_size_t flags)
932 {
933 	int err;
934 	int i, bars = 0;
935 
936 	if (atomic_add_return(1, &dev->enable_cnt) > 1)
937 		return 0;		/* already enabled */
938 
939 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
940 		if (dev->resource[i].flags & flags)
941 			bars |= (1 << i);
942 
943 	err = do_pci_enable_device(dev, bars);
944 	if (err < 0)
945 		atomic_dec(&dev->enable_cnt);
946 	return err;
947 }
948 
949 /**
950  * pci_enable_device_io - Initialize a device for use with IO space
951  * @dev: PCI device to be initialized
952  *
953  *  Initialize device before it's used by a driver. Ask low-level code
954  *  to enable I/O resources. Wake up the device if it was suspended.
955  *  Beware, this function can fail.
956  */
957 int pci_enable_device_io(struct pci_dev *dev)
958 {
959 	return __pci_enable_device_flags(dev, IORESOURCE_IO);
960 }
961 
962 /**
963  * pci_enable_device_mem - Initialize a device for use with Memory space
964  * @dev: PCI device to be initialized
965  *
966  *  Initialize device before it's used by a driver. Ask low-level code
967  *  to enable Memory resources. Wake up the device if it was suspended.
968  *  Beware, this function can fail.
969  */
970 int pci_enable_device_mem(struct pci_dev *dev)
971 {
972 	return __pci_enable_device_flags(dev, IORESOURCE_MEM);
973 }
974 
975 /**
976  * pci_enable_device - Initialize device before it's used by a driver.
977  * @dev: PCI device to be initialized
978  *
979  *  Initialize device before it's used by a driver. Ask low-level code
980  *  to enable I/O and memory. Wake up the device if it was suspended.
981  *  Beware, this function can fail.
982  *
983  *  Note we don't actually enable the device many times if we call
984  *  this function repeatedly (we just increment the count).
985  */
986 int pci_enable_device(struct pci_dev *dev)
987 {
988 	return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
989 }
990 
991 /*
992  * Managed PCI resources.  This manages device on/off, intx/msi/msix
993  * on/off and BAR regions.  pci_dev itself records msi/msix status, so
994  * there's no need to track it separately.  pci_devres is initialized
995  * when a device is enabled using managed PCI device enable interface.
996  */
997 struct pci_devres {
998 	unsigned int enabled:1;
999 	unsigned int pinned:1;
1000 	unsigned int orig_intx:1;
1001 	unsigned int restore_intx:1;
1002 	u32 region_mask;
1003 };
1004 
1005 static void pcim_release(struct device *gendev, void *res)
1006 {
1007 	struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
1008 	struct pci_devres *this = res;
1009 	int i;
1010 
1011 	if (dev->msi_enabled)
1012 		pci_disable_msi(dev);
1013 	if (dev->msix_enabled)
1014 		pci_disable_msix(dev);
1015 
1016 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1017 		if (this->region_mask & (1 << i))
1018 			pci_release_region(dev, i);
1019 
1020 	if (this->restore_intx)
1021 		pci_intx(dev, this->orig_intx);
1022 
1023 	if (this->enabled && !this->pinned)
1024 		pci_disable_device(dev);
1025 }
1026 
1027 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
1028 {
1029 	struct pci_devres *dr, *new_dr;
1030 
1031 	dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1032 	if (dr)
1033 		return dr;
1034 
1035 	new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1036 	if (!new_dr)
1037 		return NULL;
1038 	return devres_get(&pdev->dev, new_dr, NULL, NULL);
1039 }
1040 
1041 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
1042 {
1043 	if (pci_is_managed(pdev))
1044 		return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1045 	return NULL;
1046 }
1047 
1048 /**
1049  * pcim_enable_device - Managed pci_enable_device()
1050  * @pdev: PCI device to be initialized
1051  *
1052  * Managed pci_enable_device().
1053  */
1054 int pcim_enable_device(struct pci_dev *pdev)
1055 {
1056 	struct pci_devres *dr;
1057 	int rc;
1058 
1059 	dr = get_pci_dr(pdev);
1060 	if (unlikely(!dr))
1061 		return -ENOMEM;
1062 	if (dr->enabled)
1063 		return 0;
1064 
1065 	rc = pci_enable_device(pdev);
1066 	if (!rc) {
1067 		pdev->is_managed = 1;
1068 		dr->enabled = 1;
1069 	}
1070 	return rc;
1071 }
1072 
1073 /**
1074  * pcim_pin_device - Pin managed PCI device
1075  * @pdev: PCI device to pin
1076  *
1077  * Pin managed PCI device @pdev.  Pinned device won't be disabled on
1078  * driver detach.  @pdev must have been enabled with
1079  * pcim_enable_device().
1080  */
1081 void pcim_pin_device(struct pci_dev *pdev)
1082 {
1083 	struct pci_devres *dr;
1084 
1085 	dr = find_pci_dr(pdev);
1086 	WARN_ON(!dr || !dr->enabled);
1087 	if (dr)
1088 		dr->pinned = 1;
1089 }
1090 
1091 /**
1092  * pcibios_disable_device - disable arch specific PCI resources for device dev
1093  * @dev: the PCI device to disable
1094  *
1095  * Disables architecture specific PCI resources for the device. This
1096  * is the default implementation. Architecture implementations can
1097  * override this.
1098  */
1099 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
1100 
1101 static void do_pci_disable_device(struct pci_dev *dev)
1102 {
1103 	u16 pci_command;
1104 
1105 	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1106 	if (pci_command & PCI_COMMAND_MASTER) {
1107 		pci_command &= ~PCI_COMMAND_MASTER;
1108 		pci_write_config_word(dev, PCI_COMMAND, pci_command);
1109 	}
1110 
1111 	pcibios_disable_device(dev);
1112 }
1113 
1114 /**
1115  * pci_disable_enabled_device - Disable device without updating enable_cnt
1116  * @dev: PCI device to disable
1117  *
1118  * NOTE: This function is a backend of PCI power management routines and is
1119  * not supposed to be called drivers.
1120  */
1121 void pci_disable_enabled_device(struct pci_dev *dev)
1122 {
1123 	if (pci_is_enabled(dev))
1124 		do_pci_disable_device(dev);
1125 }
1126 
1127 /**
1128  * pci_disable_device - Disable PCI device after use
1129  * @dev: PCI device to be disabled
1130  *
1131  * Signal to the system that the PCI device is not in use by the system
1132  * anymore.  This only involves disabling PCI bus-mastering, if active.
1133  *
1134  * Note we don't actually disable the device until all callers of
1135  * pci_device_enable() have called pci_device_disable().
1136  */
1137 void
1138 pci_disable_device(struct pci_dev *dev)
1139 {
1140 	struct pci_devres *dr;
1141 
1142 	dr = find_pci_dr(dev);
1143 	if (dr)
1144 		dr->enabled = 0;
1145 
1146 	if (atomic_sub_return(1, &dev->enable_cnt) != 0)
1147 		return;
1148 
1149 	do_pci_disable_device(dev);
1150 
1151 	dev->is_busmaster = 0;
1152 }
1153 
1154 /**
1155  * pcibios_set_pcie_reset_state - set reset state for device dev
1156  * @dev: the PCI-E device reset
1157  * @state: Reset state to enter into
1158  *
1159  *
1160  * Sets the PCI-E reset state for the device. This is the default
1161  * implementation. Architecture implementations can override this.
1162  */
1163 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
1164 							enum pcie_reset_state state)
1165 {
1166 	return -EINVAL;
1167 }
1168 
1169 /**
1170  * pci_set_pcie_reset_state - set reset state for device dev
1171  * @dev: the PCI-E device reset
1172  * @state: Reset state to enter into
1173  *
1174  *
1175  * Sets the PCI reset state for the device.
1176  */
1177 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1178 {
1179 	return pcibios_set_pcie_reset_state(dev, state);
1180 }
1181 
1182 /**
1183  * pci_pme_capable - check the capability of PCI device to generate PME#
1184  * @dev: PCI device to handle.
1185  * @state: PCI state from which device will issue PME#.
1186  */
1187 bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1188 {
1189 	if (!dev->pm_cap)
1190 		return false;
1191 
1192 	return !!(dev->pme_support & (1 << state));
1193 }
1194 
1195 /**
1196  * pci_pme_active - enable or disable PCI device's PME# function
1197  * @dev: PCI device to handle.
1198  * @enable: 'true' to enable PME# generation; 'false' to disable it.
1199  *
1200  * The caller must verify that the device is capable of generating PME# before
1201  * calling this function with @enable equal to 'true'.
1202  */
1203 void pci_pme_active(struct pci_dev *dev, bool enable)
1204 {
1205 	u16 pmcsr;
1206 
1207 	if (!dev->pm_cap)
1208 		return;
1209 
1210 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1211 	/* Clear PME_Status by writing 1 to it and enable PME# */
1212 	pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1213 	if (!enable)
1214 		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1215 
1216 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1217 
1218 	dev_printk(KERN_DEBUG, &dev->dev, "PME# %s\n",
1219 			enable ? "enabled" : "disabled");
1220 }
1221 
1222 /**
1223  * pci_enable_wake - enable PCI device as wakeup event source
1224  * @dev: PCI device affected
1225  * @state: PCI state from which device will issue wakeup events
1226  * @enable: True to enable event generation; false to disable
1227  *
1228  * This enables the device as a wakeup event source, or disables it.
1229  * When such events involves platform-specific hooks, those hooks are
1230  * called automatically by this routine.
1231  *
1232  * Devices with legacy power management (no standard PCI PM capabilities)
1233  * always require such platform hooks.
1234  *
1235  * RETURN VALUE:
1236  * 0 is returned on success
1237  * -EINVAL is returned if device is not supposed to wake up the system
1238  * Error code depending on the platform is returned if both the platform and
1239  * the native mechanism fail to enable the generation of wake-up events
1240  */
1241 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool enable)
1242 {
1243 	int ret = 0;
1244 
1245 	if (enable && !device_may_wakeup(&dev->dev))
1246 		return -EINVAL;
1247 
1248 	/* Don't do the same thing twice in a row for one device. */
1249 	if (!!enable == !!dev->wakeup_prepared)
1250 		return 0;
1251 
1252 	/*
1253 	 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1254 	 * Anderson we should be doing PME# wake enable followed by ACPI wake
1255 	 * enable.  To disable wake-up we call the platform first, for symmetry.
1256 	 */
1257 
1258 	if (enable) {
1259 		int error;
1260 
1261 		if (pci_pme_capable(dev, state))
1262 			pci_pme_active(dev, true);
1263 		else
1264 			ret = 1;
1265 		error = platform_pci_sleep_wake(dev, true);
1266 		if (ret)
1267 			ret = error;
1268 		if (!ret)
1269 			dev->wakeup_prepared = true;
1270 	} else {
1271 		platform_pci_sleep_wake(dev, false);
1272 		pci_pme_active(dev, false);
1273 		dev->wakeup_prepared = false;
1274 	}
1275 
1276 	return ret;
1277 }
1278 
1279 /**
1280  * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1281  * @dev: PCI device to prepare
1282  * @enable: True to enable wake-up event generation; false to disable
1283  *
1284  * Many drivers want the device to wake up the system from D3_hot or D3_cold
1285  * and this function allows them to set that up cleanly - pci_enable_wake()
1286  * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1287  * ordering constraints.
1288  *
1289  * This function only returns error code if the device is not capable of
1290  * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1291  * enable wake-up power for it.
1292  */
1293 int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1294 {
1295 	return pci_pme_capable(dev, PCI_D3cold) ?
1296 			pci_enable_wake(dev, PCI_D3cold, enable) :
1297 			pci_enable_wake(dev, PCI_D3hot, enable);
1298 }
1299 
1300 /**
1301  * pci_target_state - find an appropriate low power state for a given PCI dev
1302  * @dev: PCI device
1303  *
1304  * Use underlying platform code to find a supported low power state for @dev.
1305  * If the platform can't manage @dev, return the deepest state from which it
1306  * can generate wake events, based on any available PME info.
1307  */
1308 pci_power_t pci_target_state(struct pci_dev *dev)
1309 {
1310 	pci_power_t target_state = PCI_D3hot;
1311 
1312 	if (platform_pci_power_manageable(dev)) {
1313 		/*
1314 		 * Call the platform to choose the target state of the device
1315 		 * and enable wake-up from this state if supported.
1316 		 */
1317 		pci_power_t state = platform_pci_choose_state(dev);
1318 
1319 		switch (state) {
1320 		case PCI_POWER_ERROR:
1321 		case PCI_UNKNOWN:
1322 			break;
1323 		case PCI_D1:
1324 		case PCI_D2:
1325 			if (pci_no_d1d2(dev))
1326 				break;
1327 		default:
1328 			target_state = state;
1329 		}
1330 	} else if (!dev->pm_cap) {
1331 		target_state = PCI_D0;
1332 	} else if (device_may_wakeup(&dev->dev)) {
1333 		/*
1334 		 * Find the deepest state from which the device can generate
1335 		 * wake-up events, make it the target state and enable device
1336 		 * to generate PME#.
1337 		 */
1338 		if (dev->pme_support) {
1339 			while (target_state
1340 			      && !(dev->pme_support & (1 << target_state)))
1341 				target_state--;
1342 		}
1343 	}
1344 
1345 	return target_state;
1346 }
1347 
1348 /**
1349  * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1350  * @dev: Device to handle.
1351  *
1352  * Choose the power state appropriate for the device depending on whether
1353  * it can wake up the system and/or is power manageable by the platform
1354  * (PCI_D3hot is the default) and put the device into that state.
1355  */
1356 int pci_prepare_to_sleep(struct pci_dev *dev)
1357 {
1358 	pci_power_t target_state = pci_target_state(dev);
1359 	int error;
1360 
1361 	if (target_state == PCI_POWER_ERROR)
1362 		return -EIO;
1363 
1364 	pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
1365 
1366 	error = pci_set_power_state(dev, target_state);
1367 
1368 	if (error)
1369 		pci_enable_wake(dev, target_state, false);
1370 
1371 	return error;
1372 }
1373 
1374 /**
1375  * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1376  * @dev: Device to handle.
1377  *
1378  * Disable device's sytem wake-up capability and put it into D0.
1379  */
1380 int pci_back_from_sleep(struct pci_dev *dev)
1381 {
1382 	pci_enable_wake(dev, PCI_D0, false);
1383 	return pci_set_power_state(dev, PCI_D0);
1384 }
1385 
1386 /**
1387  * pci_pm_init - Initialize PM functions of given PCI device
1388  * @dev: PCI device to handle.
1389  */
1390 void pci_pm_init(struct pci_dev *dev)
1391 {
1392 	int pm;
1393 	u16 pmc;
1394 
1395 	dev->wakeup_prepared = false;
1396 	dev->pm_cap = 0;
1397 
1398 	/* find PCI PM capability in list */
1399 	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
1400 	if (!pm)
1401 		return;
1402 	/* Check device's ability to generate PME# */
1403 	pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
1404 
1405 	if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
1406 		dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
1407 			pmc & PCI_PM_CAP_VER_MASK);
1408 		return;
1409 	}
1410 
1411 	dev->pm_cap = pm;
1412 
1413 	dev->d1_support = false;
1414 	dev->d2_support = false;
1415 	if (!pci_no_d1d2(dev)) {
1416 		if (pmc & PCI_PM_CAP_D1)
1417 			dev->d1_support = true;
1418 		if (pmc & PCI_PM_CAP_D2)
1419 			dev->d2_support = true;
1420 
1421 		if (dev->d1_support || dev->d2_support)
1422 			dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
1423 				   dev->d1_support ? " D1" : "",
1424 				   dev->d2_support ? " D2" : "");
1425 	}
1426 
1427 	pmc &= PCI_PM_CAP_PME_MASK;
1428 	if (pmc) {
1429 		dev_printk(KERN_DEBUG, &dev->dev,
1430 			 "PME# supported from%s%s%s%s%s\n",
1431 			 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
1432 			 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
1433 			 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
1434 			 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
1435 			 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
1436 		dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
1437 		/*
1438 		 * Make device's PM flags reflect the wake-up capability, but
1439 		 * let the user space enable it to wake up the system as needed.
1440 		 */
1441 		device_set_wakeup_capable(&dev->dev, true);
1442 		device_set_wakeup_enable(&dev->dev, false);
1443 		/* Disable the PME# generation functionality */
1444 		pci_pme_active(dev, false);
1445 	} else {
1446 		dev->pme_support = 0;
1447 	}
1448 }
1449 
1450 /**
1451  * platform_pci_wakeup_init - init platform wakeup if present
1452  * @dev: PCI device
1453  *
1454  * Some devices don't have PCI PM caps but can still generate wakeup
1455  * events through platform methods (like ACPI events).  If @dev supports
1456  * platform wakeup events, set the device flag to indicate as much.  This
1457  * may be redundant if the device also supports PCI PM caps, but double
1458  * initialization should be safe in that case.
1459  */
1460 void platform_pci_wakeup_init(struct pci_dev *dev)
1461 {
1462 	if (!platform_pci_can_wakeup(dev))
1463 		return;
1464 
1465 	device_set_wakeup_capable(&dev->dev, true);
1466 	device_set_wakeup_enable(&dev->dev, false);
1467 	platform_pci_sleep_wake(dev, false);
1468 }
1469 
1470 /**
1471  * pci_add_save_buffer - allocate buffer for saving given capability registers
1472  * @dev: the PCI device
1473  * @cap: the capability to allocate the buffer for
1474  * @size: requested size of the buffer
1475  */
1476 static int pci_add_cap_save_buffer(
1477 	struct pci_dev *dev, char cap, unsigned int size)
1478 {
1479 	int pos;
1480 	struct pci_cap_saved_state *save_state;
1481 
1482 	pos = pci_find_capability(dev, cap);
1483 	if (pos <= 0)
1484 		return 0;
1485 
1486 	save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
1487 	if (!save_state)
1488 		return -ENOMEM;
1489 
1490 	save_state->cap_nr = cap;
1491 	pci_add_saved_cap(dev, save_state);
1492 
1493 	return 0;
1494 }
1495 
1496 /**
1497  * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
1498  * @dev: the PCI device
1499  */
1500 void pci_allocate_cap_save_buffers(struct pci_dev *dev)
1501 {
1502 	int error;
1503 
1504 	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
1505 					PCI_EXP_SAVE_REGS * sizeof(u16));
1506 	if (error)
1507 		dev_err(&dev->dev,
1508 			"unable to preallocate PCI Express save buffer\n");
1509 
1510 	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
1511 	if (error)
1512 		dev_err(&dev->dev,
1513 			"unable to preallocate PCI-X save buffer\n");
1514 }
1515 
1516 /**
1517  * pci_enable_ari - enable ARI forwarding if hardware support it
1518  * @dev: the PCI device
1519  */
1520 void pci_enable_ari(struct pci_dev *dev)
1521 {
1522 	int pos;
1523 	u32 cap;
1524 	u16 ctrl;
1525 	struct pci_dev *bridge;
1526 
1527 	if (!pci_is_pcie(dev) || dev->devfn)
1528 		return;
1529 
1530 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1531 	if (!pos)
1532 		return;
1533 
1534 	bridge = dev->bus->self;
1535 	if (!bridge || !pci_is_pcie(bridge))
1536 		return;
1537 
1538 	pos = pci_pcie_cap(bridge);
1539 	if (!pos)
1540 		return;
1541 
1542 	pci_read_config_dword(bridge, pos + PCI_EXP_DEVCAP2, &cap);
1543 	if (!(cap & PCI_EXP_DEVCAP2_ARI))
1544 		return;
1545 
1546 	pci_read_config_word(bridge, pos + PCI_EXP_DEVCTL2, &ctrl);
1547 	ctrl |= PCI_EXP_DEVCTL2_ARI;
1548 	pci_write_config_word(bridge, pos + PCI_EXP_DEVCTL2, ctrl);
1549 
1550 	bridge->ari_enabled = 1;
1551 }
1552 
1553 static int pci_acs_enable;
1554 
1555 /**
1556  * pci_request_acs - ask for ACS to be enabled if supported
1557  */
1558 void pci_request_acs(void)
1559 {
1560 	pci_acs_enable = 1;
1561 }
1562 
1563 /**
1564  * pci_enable_acs - enable ACS if hardware support it
1565  * @dev: the PCI device
1566  */
1567 void pci_enable_acs(struct pci_dev *dev)
1568 {
1569 	int pos;
1570 	u16 cap;
1571 	u16 ctrl;
1572 
1573 	if (!pci_acs_enable)
1574 		return;
1575 
1576 	if (!pci_is_pcie(dev))
1577 		return;
1578 
1579 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
1580 	if (!pos)
1581 		return;
1582 
1583 	pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
1584 	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
1585 
1586 	/* Source Validation */
1587 	ctrl |= (cap & PCI_ACS_SV);
1588 
1589 	/* P2P Request Redirect */
1590 	ctrl |= (cap & PCI_ACS_RR);
1591 
1592 	/* P2P Completion Redirect */
1593 	ctrl |= (cap & PCI_ACS_CR);
1594 
1595 	/* Upstream Forwarding */
1596 	ctrl |= (cap & PCI_ACS_UF);
1597 
1598 	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
1599 }
1600 
1601 /**
1602  * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
1603  * @dev: the PCI device
1604  * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTD, 4=INTD)
1605  *
1606  * Perform INTx swizzling for a device behind one level of bridge.  This is
1607  * required by section 9.1 of the PCI-to-PCI bridge specification for devices
1608  * behind bridges on add-in cards.  For devices with ARI enabled, the slot
1609  * number is always 0 (see the Implementation Note in section 2.2.8.1 of
1610  * the PCI Express Base Specification, Revision 2.1)
1611  */
1612 u8 pci_swizzle_interrupt_pin(struct pci_dev *dev, u8 pin)
1613 {
1614 	int slot;
1615 
1616 	if (pci_ari_enabled(dev->bus))
1617 		slot = 0;
1618 	else
1619 		slot = PCI_SLOT(dev->devfn);
1620 
1621 	return (((pin - 1) + slot) % 4) + 1;
1622 }
1623 
1624 int
1625 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
1626 {
1627 	u8 pin;
1628 
1629 	pin = dev->pin;
1630 	if (!pin)
1631 		return -1;
1632 
1633 	while (!pci_is_root_bus(dev->bus)) {
1634 		pin = pci_swizzle_interrupt_pin(dev, pin);
1635 		dev = dev->bus->self;
1636 	}
1637 	*bridge = dev;
1638 	return pin;
1639 }
1640 
1641 /**
1642  * pci_common_swizzle - swizzle INTx all the way to root bridge
1643  * @dev: the PCI device
1644  * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
1645  *
1646  * Perform INTx swizzling for a device.  This traverses through all PCI-to-PCI
1647  * bridges all the way up to a PCI root bus.
1648  */
1649 u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
1650 {
1651 	u8 pin = *pinp;
1652 
1653 	while (!pci_is_root_bus(dev->bus)) {
1654 		pin = pci_swizzle_interrupt_pin(dev, pin);
1655 		dev = dev->bus->self;
1656 	}
1657 	*pinp = pin;
1658 	return PCI_SLOT(dev->devfn);
1659 }
1660 
1661 /**
1662  *	pci_release_region - Release a PCI bar
1663  *	@pdev: PCI device whose resources were previously reserved by pci_request_region
1664  *	@bar: BAR to release
1665  *
1666  *	Releases the PCI I/O and memory resources previously reserved by a
1667  *	successful call to pci_request_region.  Call this function only
1668  *	after all use of the PCI regions has ceased.
1669  */
1670 void pci_release_region(struct pci_dev *pdev, int bar)
1671 {
1672 	struct pci_devres *dr;
1673 
1674 	if (pci_resource_len(pdev, bar) == 0)
1675 		return;
1676 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1677 		release_region(pci_resource_start(pdev, bar),
1678 				pci_resource_len(pdev, bar));
1679 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1680 		release_mem_region(pci_resource_start(pdev, bar),
1681 				pci_resource_len(pdev, bar));
1682 
1683 	dr = find_pci_dr(pdev);
1684 	if (dr)
1685 		dr->region_mask &= ~(1 << bar);
1686 }
1687 
1688 /**
1689  *	__pci_request_region - Reserved PCI I/O and memory resource
1690  *	@pdev: PCI device whose resources are to be reserved
1691  *	@bar: BAR to be reserved
1692  *	@res_name: Name to be associated with resource.
1693  *	@exclusive: whether the region access is exclusive or not
1694  *
1695  *	Mark the PCI region associated with PCI device @pdev BR @bar as
1696  *	being reserved by owner @res_name.  Do not access any
1697  *	address inside the PCI regions unless this call returns
1698  *	successfully.
1699  *
1700  *	If @exclusive is set, then the region is marked so that userspace
1701  *	is explicitly not allowed to map the resource via /dev/mem or
1702  * 	sysfs MMIO access.
1703  *
1704  *	Returns 0 on success, or %EBUSY on error.  A warning
1705  *	message is also printed on failure.
1706  */
1707 static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
1708 									int exclusive)
1709 {
1710 	struct pci_devres *dr;
1711 
1712 	if (pci_resource_len(pdev, bar) == 0)
1713 		return 0;
1714 
1715 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1716 		if (!request_region(pci_resource_start(pdev, bar),
1717 			    pci_resource_len(pdev, bar), res_name))
1718 			goto err_out;
1719 	}
1720 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1721 		if (!__request_mem_region(pci_resource_start(pdev, bar),
1722 					pci_resource_len(pdev, bar), res_name,
1723 					exclusive))
1724 			goto err_out;
1725 	}
1726 
1727 	dr = find_pci_dr(pdev);
1728 	if (dr)
1729 		dr->region_mask |= 1 << bar;
1730 
1731 	return 0;
1732 
1733 err_out:
1734 	dev_warn(&pdev->dev, "BAR %d: can't reserve %pR\n", bar,
1735 		 &pdev->resource[bar]);
1736 	return -EBUSY;
1737 }
1738 
1739 /**
1740  *	pci_request_region - Reserve PCI I/O and memory resource
1741  *	@pdev: PCI device whose resources are to be reserved
1742  *	@bar: BAR to be reserved
1743  *	@res_name: Name to be associated with resource
1744  *
1745  *	Mark the PCI region associated with PCI device @pdev BAR @bar as
1746  *	being reserved by owner @res_name.  Do not access any
1747  *	address inside the PCI regions unless this call returns
1748  *	successfully.
1749  *
1750  *	Returns 0 on success, or %EBUSY on error.  A warning
1751  *	message is also printed on failure.
1752  */
1753 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1754 {
1755 	return __pci_request_region(pdev, bar, res_name, 0);
1756 }
1757 
1758 /**
1759  *	pci_request_region_exclusive - Reserved PCI I/O and memory resource
1760  *	@pdev: PCI device whose resources are to be reserved
1761  *	@bar: BAR to be reserved
1762  *	@res_name: Name to be associated with resource.
1763  *
1764  *	Mark the PCI region associated with PCI device @pdev BR @bar as
1765  *	being reserved by owner @res_name.  Do not access any
1766  *	address inside the PCI regions unless this call returns
1767  *	successfully.
1768  *
1769  *	Returns 0 on success, or %EBUSY on error.  A warning
1770  *	message is also printed on failure.
1771  *
1772  *	The key difference that _exclusive makes it that userspace is
1773  *	explicitly not allowed to map the resource via /dev/mem or
1774  * 	sysfs.
1775  */
1776 int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name)
1777 {
1778 	return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
1779 }
1780 /**
1781  * pci_release_selected_regions - Release selected PCI I/O and memory resources
1782  * @pdev: PCI device whose resources were previously reserved
1783  * @bars: Bitmask of BARs to be released
1784  *
1785  * Release selected PCI I/O and memory resources previously reserved.
1786  * Call this function only after all use of the PCI regions has ceased.
1787  */
1788 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1789 {
1790 	int i;
1791 
1792 	for (i = 0; i < 6; i++)
1793 		if (bars & (1 << i))
1794 			pci_release_region(pdev, i);
1795 }
1796 
1797 int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
1798 				 const char *res_name, int excl)
1799 {
1800 	int i;
1801 
1802 	for (i = 0; i < 6; i++)
1803 		if (bars & (1 << i))
1804 			if (__pci_request_region(pdev, i, res_name, excl))
1805 				goto err_out;
1806 	return 0;
1807 
1808 err_out:
1809 	while(--i >= 0)
1810 		if (bars & (1 << i))
1811 			pci_release_region(pdev, i);
1812 
1813 	return -EBUSY;
1814 }
1815 
1816 
1817 /**
1818  * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
1819  * @pdev: PCI device whose resources are to be reserved
1820  * @bars: Bitmask of BARs to be requested
1821  * @res_name: Name to be associated with resource
1822  */
1823 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
1824 				 const char *res_name)
1825 {
1826 	return __pci_request_selected_regions(pdev, bars, res_name, 0);
1827 }
1828 
1829 int pci_request_selected_regions_exclusive(struct pci_dev *pdev,
1830 				 int bars, const char *res_name)
1831 {
1832 	return __pci_request_selected_regions(pdev, bars, res_name,
1833 			IORESOURCE_EXCLUSIVE);
1834 }
1835 
1836 /**
1837  *	pci_release_regions - Release reserved PCI I/O and memory resources
1838  *	@pdev: PCI device whose resources were previously reserved by pci_request_regions
1839  *
1840  *	Releases all PCI I/O and memory resources previously reserved by a
1841  *	successful call to pci_request_regions.  Call this function only
1842  *	after all use of the PCI regions has ceased.
1843  */
1844 
1845 void pci_release_regions(struct pci_dev *pdev)
1846 {
1847 	pci_release_selected_regions(pdev, (1 << 6) - 1);
1848 }
1849 
1850 /**
1851  *	pci_request_regions - Reserved PCI I/O and memory resources
1852  *	@pdev: PCI device whose resources are to be reserved
1853  *	@res_name: Name to be associated with resource.
1854  *
1855  *	Mark all PCI regions associated with PCI device @pdev as
1856  *	being reserved by owner @res_name.  Do not access any
1857  *	address inside the PCI regions unless this call returns
1858  *	successfully.
1859  *
1860  *	Returns 0 on success, or %EBUSY on error.  A warning
1861  *	message is also printed on failure.
1862  */
1863 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
1864 {
1865 	return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
1866 }
1867 
1868 /**
1869  *	pci_request_regions_exclusive - Reserved PCI I/O and memory resources
1870  *	@pdev: PCI device whose resources are to be reserved
1871  *	@res_name: Name to be associated with resource.
1872  *
1873  *	Mark all PCI regions associated with PCI device @pdev as
1874  *	being reserved by owner @res_name.  Do not access any
1875  *	address inside the PCI regions unless this call returns
1876  *	successfully.
1877  *
1878  *	pci_request_regions_exclusive() will mark the region so that
1879  * 	/dev/mem and the sysfs MMIO access will not be allowed.
1880  *
1881  *	Returns 0 on success, or %EBUSY on error.  A warning
1882  *	message is also printed on failure.
1883  */
1884 int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
1885 {
1886 	return pci_request_selected_regions_exclusive(pdev,
1887 					((1 << 6) - 1), res_name);
1888 }
1889 
1890 static void __pci_set_master(struct pci_dev *dev, bool enable)
1891 {
1892 	u16 old_cmd, cmd;
1893 
1894 	pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
1895 	if (enable)
1896 		cmd = old_cmd | PCI_COMMAND_MASTER;
1897 	else
1898 		cmd = old_cmd & ~PCI_COMMAND_MASTER;
1899 	if (cmd != old_cmd) {
1900 		dev_dbg(&dev->dev, "%s bus mastering\n",
1901 			enable ? "enabling" : "disabling");
1902 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1903 	}
1904 	dev->is_busmaster = enable;
1905 }
1906 
1907 /**
1908  * pci_set_master - enables bus-mastering for device dev
1909  * @dev: the PCI device to enable
1910  *
1911  * Enables bus-mastering on the device and calls pcibios_set_master()
1912  * to do the needed arch specific settings.
1913  */
1914 void pci_set_master(struct pci_dev *dev)
1915 {
1916 	__pci_set_master(dev, true);
1917 	pcibios_set_master(dev);
1918 }
1919 
1920 /**
1921  * pci_clear_master - disables bus-mastering for device dev
1922  * @dev: the PCI device to disable
1923  */
1924 void pci_clear_master(struct pci_dev *dev)
1925 {
1926 	__pci_set_master(dev, false);
1927 }
1928 
1929 /**
1930  * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1931  * @dev: the PCI device for which MWI is to be enabled
1932  *
1933  * Helper function for pci_set_mwi.
1934  * Originally copied from drivers/net/acenic.c.
1935  * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1936  *
1937  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1938  */
1939 int pci_set_cacheline_size(struct pci_dev *dev)
1940 {
1941 	u8 cacheline_size;
1942 
1943 	if (!pci_cache_line_size)
1944 		return -EINVAL;
1945 
1946 	/* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1947 	   equal to or multiple of the right value. */
1948 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1949 	if (cacheline_size >= pci_cache_line_size &&
1950 	    (cacheline_size % pci_cache_line_size) == 0)
1951 		return 0;
1952 
1953 	/* Write the correct value. */
1954 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1955 	/* Read it back. */
1956 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1957 	if (cacheline_size == pci_cache_line_size)
1958 		return 0;
1959 
1960 	dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
1961 		   "supported\n", pci_cache_line_size << 2);
1962 
1963 	return -EINVAL;
1964 }
1965 EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
1966 
1967 #ifdef PCI_DISABLE_MWI
1968 int pci_set_mwi(struct pci_dev *dev)
1969 {
1970 	return 0;
1971 }
1972 
1973 int pci_try_set_mwi(struct pci_dev *dev)
1974 {
1975 	return 0;
1976 }
1977 
1978 void pci_clear_mwi(struct pci_dev *dev)
1979 {
1980 }
1981 
1982 #else
1983 
1984 /**
1985  * pci_set_mwi - enables memory-write-invalidate PCI transaction
1986  * @dev: the PCI device for which MWI is enabled
1987  *
1988  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1989  *
1990  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1991  */
1992 int
1993 pci_set_mwi(struct pci_dev *dev)
1994 {
1995 	int rc;
1996 	u16 cmd;
1997 
1998 	rc = pci_set_cacheline_size(dev);
1999 	if (rc)
2000 		return rc;
2001 
2002 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2003 	if (! (cmd & PCI_COMMAND_INVALIDATE)) {
2004 		dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
2005 		cmd |= PCI_COMMAND_INVALIDATE;
2006 		pci_write_config_word(dev, PCI_COMMAND, cmd);
2007 	}
2008 
2009 	return 0;
2010 }
2011 
2012 /**
2013  * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
2014  * @dev: the PCI device for which MWI is enabled
2015  *
2016  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2017  * Callers are not required to check the return value.
2018  *
2019  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2020  */
2021 int pci_try_set_mwi(struct pci_dev *dev)
2022 {
2023 	int rc = pci_set_mwi(dev);
2024 	return rc;
2025 }
2026 
2027 /**
2028  * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
2029  * @dev: the PCI device to disable
2030  *
2031  * Disables PCI Memory-Write-Invalidate transaction on the device
2032  */
2033 void
2034 pci_clear_mwi(struct pci_dev *dev)
2035 {
2036 	u16 cmd;
2037 
2038 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2039 	if (cmd & PCI_COMMAND_INVALIDATE) {
2040 		cmd &= ~PCI_COMMAND_INVALIDATE;
2041 		pci_write_config_word(dev, PCI_COMMAND, cmd);
2042 	}
2043 }
2044 #endif /* ! PCI_DISABLE_MWI */
2045 
2046 /**
2047  * pci_intx - enables/disables PCI INTx for device dev
2048  * @pdev: the PCI device to operate on
2049  * @enable: boolean: whether to enable or disable PCI INTx
2050  *
2051  * Enables/disables PCI INTx for device dev
2052  */
2053 void
2054 pci_intx(struct pci_dev *pdev, int enable)
2055 {
2056 	u16 pci_command, new;
2057 
2058 	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
2059 
2060 	if (enable) {
2061 		new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
2062 	} else {
2063 		new = pci_command | PCI_COMMAND_INTX_DISABLE;
2064 	}
2065 
2066 	if (new != pci_command) {
2067 		struct pci_devres *dr;
2068 
2069 		pci_write_config_word(pdev, PCI_COMMAND, new);
2070 
2071 		dr = find_pci_dr(pdev);
2072 		if (dr && !dr->restore_intx) {
2073 			dr->restore_intx = 1;
2074 			dr->orig_intx = !enable;
2075 		}
2076 	}
2077 }
2078 
2079 /**
2080  * pci_msi_off - disables any msi or msix capabilities
2081  * @dev: the PCI device to operate on
2082  *
2083  * If you want to use msi see pci_enable_msi and friends.
2084  * This is a lower level primitive that allows us to disable
2085  * msi operation at the device level.
2086  */
2087 void pci_msi_off(struct pci_dev *dev)
2088 {
2089 	int pos;
2090 	u16 control;
2091 
2092 	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
2093 	if (pos) {
2094 		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
2095 		control &= ~PCI_MSI_FLAGS_ENABLE;
2096 		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
2097 	}
2098 	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
2099 	if (pos) {
2100 		pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
2101 		control &= ~PCI_MSIX_FLAGS_ENABLE;
2102 		pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
2103 	}
2104 }
2105 
2106 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
2107 /*
2108  * These can be overridden by arch-specific implementations
2109  */
2110 int
2111 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
2112 {
2113 	if (!pci_dma_supported(dev, mask))
2114 		return -EIO;
2115 
2116 	dev->dma_mask = mask;
2117 	dev_dbg(&dev->dev, "using %dbit DMA mask\n", fls64(mask));
2118 
2119 	return 0;
2120 }
2121 
2122 int
2123 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
2124 {
2125 	if (!pci_dma_supported(dev, mask))
2126 		return -EIO;
2127 
2128 	dev->dev.coherent_dma_mask = mask;
2129 	dev_dbg(&dev->dev, "using %dbit consistent DMA mask\n", fls64(mask));
2130 
2131 	return 0;
2132 }
2133 #endif
2134 
2135 #ifndef HAVE_ARCH_PCI_SET_DMA_MAX_SEGMENT_SIZE
2136 int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
2137 {
2138 	return dma_set_max_seg_size(&dev->dev, size);
2139 }
2140 EXPORT_SYMBOL(pci_set_dma_max_seg_size);
2141 #endif
2142 
2143 #ifndef HAVE_ARCH_PCI_SET_DMA_SEGMENT_BOUNDARY
2144 int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
2145 {
2146 	return dma_set_seg_boundary(&dev->dev, mask);
2147 }
2148 EXPORT_SYMBOL(pci_set_dma_seg_boundary);
2149 #endif
2150 
2151 static int pcie_flr(struct pci_dev *dev, int probe)
2152 {
2153 	int i;
2154 	int pos;
2155 	u32 cap;
2156 	u16 status, control;
2157 
2158 	pos = pci_pcie_cap(dev);
2159 	if (!pos)
2160 		return -ENOTTY;
2161 
2162 	pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP, &cap);
2163 	if (!(cap & PCI_EXP_DEVCAP_FLR))
2164 		return -ENOTTY;
2165 
2166 	if (probe)
2167 		return 0;
2168 
2169 	/* Wait for Transaction Pending bit clean */
2170 	for (i = 0; i < 4; i++) {
2171 		if (i)
2172 			msleep((1 << (i - 1)) * 100);
2173 
2174 		pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &status);
2175 		if (!(status & PCI_EXP_DEVSTA_TRPND))
2176 			goto clear;
2177 	}
2178 
2179 	dev_err(&dev->dev, "transaction is not cleared; "
2180 			"proceeding with reset anyway\n");
2181 
2182 clear:
2183 	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &control);
2184 	control |= PCI_EXP_DEVCTL_BCR_FLR;
2185 	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, control);
2186 
2187 	msleep(100);
2188 
2189 	return 0;
2190 }
2191 
2192 static int pci_af_flr(struct pci_dev *dev, int probe)
2193 {
2194 	int i;
2195 	int pos;
2196 	u8 cap;
2197 	u8 status;
2198 
2199 	pos = pci_find_capability(dev, PCI_CAP_ID_AF);
2200 	if (!pos)
2201 		return -ENOTTY;
2202 
2203 	pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
2204 	if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
2205 		return -ENOTTY;
2206 
2207 	if (probe)
2208 		return 0;
2209 
2210 	/* Wait for Transaction Pending bit clean */
2211 	for (i = 0; i < 4; i++) {
2212 		if (i)
2213 			msleep((1 << (i - 1)) * 100);
2214 
2215 		pci_read_config_byte(dev, pos + PCI_AF_STATUS, &status);
2216 		if (!(status & PCI_AF_STATUS_TP))
2217 			goto clear;
2218 	}
2219 
2220 	dev_err(&dev->dev, "transaction is not cleared; "
2221 			"proceeding with reset anyway\n");
2222 
2223 clear:
2224 	pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
2225 	msleep(100);
2226 
2227 	return 0;
2228 }
2229 
2230 static int pci_pm_reset(struct pci_dev *dev, int probe)
2231 {
2232 	u16 csr;
2233 
2234 	if (!dev->pm_cap)
2235 		return -ENOTTY;
2236 
2237 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
2238 	if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
2239 		return -ENOTTY;
2240 
2241 	if (probe)
2242 		return 0;
2243 
2244 	if (dev->current_state != PCI_D0)
2245 		return -EINVAL;
2246 
2247 	csr &= ~PCI_PM_CTRL_STATE_MASK;
2248 	csr |= PCI_D3hot;
2249 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
2250 	msleep(pci_pm_d3_delay);
2251 
2252 	csr &= ~PCI_PM_CTRL_STATE_MASK;
2253 	csr |= PCI_D0;
2254 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
2255 	msleep(pci_pm_d3_delay);
2256 
2257 	return 0;
2258 }
2259 
2260 static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
2261 {
2262 	u16 ctrl;
2263 	struct pci_dev *pdev;
2264 
2265 	if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self)
2266 		return -ENOTTY;
2267 
2268 	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
2269 		if (pdev != dev)
2270 			return -ENOTTY;
2271 
2272 	if (probe)
2273 		return 0;
2274 
2275 	pci_read_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, &ctrl);
2276 	ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
2277 	pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
2278 	msleep(100);
2279 
2280 	ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
2281 	pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
2282 	msleep(100);
2283 
2284 	return 0;
2285 }
2286 
2287 static int pci_dev_reset(struct pci_dev *dev, int probe)
2288 {
2289 	int rc;
2290 
2291 	might_sleep();
2292 
2293 	if (!probe) {
2294 		pci_block_user_cfg_access(dev);
2295 		/* block PM suspend, driver probe, etc. */
2296 		down(&dev->dev.sem);
2297 	}
2298 
2299 	rc = pcie_flr(dev, probe);
2300 	if (rc != -ENOTTY)
2301 		goto done;
2302 
2303 	rc = pci_af_flr(dev, probe);
2304 	if (rc != -ENOTTY)
2305 		goto done;
2306 
2307 	rc = pci_pm_reset(dev, probe);
2308 	if (rc != -ENOTTY)
2309 		goto done;
2310 
2311 	rc = pci_parent_bus_reset(dev, probe);
2312 done:
2313 	if (!probe) {
2314 		up(&dev->dev.sem);
2315 		pci_unblock_user_cfg_access(dev);
2316 	}
2317 
2318 	return rc;
2319 }
2320 
2321 /**
2322  * __pci_reset_function - reset a PCI device function
2323  * @dev: PCI device to reset
2324  *
2325  * Some devices allow an individual function to be reset without affecting
2326  * other functions in the same device.  The PCI device must be responsive
2327  * to PCI config space in order to use this function.
2328  *
2329  * The device function is presumed to be unused when this function is called.
2330  * Resetting the device will make the contents of PCI configuration space
2331  * random, so any caller of this must be prepared to reinitialise the
2332  * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
2333  * etc.
2334  *
2335  * Returns 0 if the device function was successfully reset or negative if the
2336  * device doesn't support resetting a single function.
2337  */
2338 int __pci_reset_function(struct pci_dev *dev)
2339 {
2340 	return pci_dev_reset(dev, 0);
2341 }
2342 EXPORT_SYMBOL_GPL(__pci_reset_function);
2343 
2344 /**
2345  * pci_probe_reset_function - check whether the device can be safely reset
2346  * @dev: PCI device to reset
2347  *
2348  * Some devices allow an individual function to be reset without affecting
2349  * other functions in the same device.  The PCI device must be responsive
2350  * to PCI config space in order to use this function.
2351  *
2352  * Returns 0 if the device function can be reset or negative if the
2353  * device doesn't support resetting a single function.
2354  */
2355 int pci_probe_reset_function(struct pci_dev *dev)
2356 {
2357 	return pci_dev_reset(dev, 1);
2358 }
2359 
2360 /**
2361  * pci_reset_function - quiesce and reset a PCI device function
2362  * @dev: PCI device to reset
2363  *
2364  * Some devices allow an individual function to be reset without affecting
2365  * other functions in the same device.  The PCI device must be responsive
2366  * to PCI config space in order to use this function.
2367  *
2368  * This function does not just reset the PCI portion of a device, but
2369  * clears all the state associated with the device.  This function differs
2370  * from __pci_reset_function in that it saves and restores device state
2371  * over the reset.
2372  *
2373  * Returns 0 if the device function was successfully reset or negative if the
2374  * device doesn't support resetting a single function.
2375  */
2376 int pci_reset_function(struct pci_dev *dev)
2377 {
2378 	int rc;
2379 
2380 	rc = pci_dev_reset(dev, 1);
2381 	if (rc)
2382 		return rc;
2383 
2384 	pci_save_state(dev);
2385 
2386 	/*
2387 	 * both INTx and MSI are disabled after the Interrupt Disable bit
2388 	 * is set and the Bus Master bit is cleared.
2389 	 */
2390 	pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
2391 
2392 	rc = pci_dev_reset(dev, 0);
2393 
2394 	pci_restore_state(dev);
2395 
2396 	return rc;
2397 }
2398 EXPORT_SYMBOL_GPL(pci_reset_function);
2399 
2400 /**
2401  * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
2402  * @dev: PCI device to query
2403  *
2404  * Returns mmrbc: maximum designed memory read count in bytes
2405  *    or appropriate error value.
2406  */
2407 int pcix_get_max_mmrbc(struct pci_dev *dev)
2408 {
2409 	int err, cap;
2410 	u32 stat;
2411 
2412 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2413 	if (!cap)
2414 		return -EINVAL;
2415 
2416 	err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
2417 	if (err)
2418 		return -EINVAL;
2419 
2420 	return (stat & PCI_X_STATUS_MAX_READ) >> 12;
2421 }
2422 EXPORT_SYMBOL(pcix_get_max_mmrbc);
2423 
2424 /**
2425  * pcix_get_mmrbc - get PCI-X maximum memory read byte count
2426  * @dev: PCI device to query
2427  *
2428  * Returns mmrbc: maximum memory read count in bytes
2429  *    or appropriate error value.
2430  */
2431 int pcix_get_mmrbc(struct pci_dev *dev)
2432 {
2433 	int ret, cap;
2434 	u32 cmd;
2435 
2436 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2437 	if (!cap)
2438 		return -EINVAL;
2439 
2440 	ret = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
2441 	if (!ret)
2442 		ret = 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
2443 
2444 	return ret;
2445 }
2446 EXPORT_SYMBOL(pcix_get_mmrbc);
2447 
2448 /**
2449  * pcix_set_mmrbc - set PCI-X maximum memory read byte count
2450  * @dev: PCI device to query
2451  * @mmrbc: maximum memory read count in bytes
2452  *    valid values are 512, 1024, 2048, 4096
2453  *
2454  * If possible sets maximum memory read byte count, some bridges have erratas
2455  * that prevent this.
2456  */
2457 int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
2458 {
2459 	int cap, err = -EINVAL;
2460 	u32 stat, cmd, v, o;
2461 
2462 	if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
2463 		goto out;
2464 
2465 	v = ffs(mmrbc) - 10;
2466 
2467 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2468 	if (!cap)
2469 		goto out;
2470 
2471 	err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
2472 	if (err)
2473 		goto out;
2474 
2475 	if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
2476 		return -E2BIG;
2477 
2478 	err = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
2479 	if (err)
2480 		goto out;
2481 
2482 	o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
2483 	if (o != v) {
2484 		if (v > o && dev->bus &&
2485 		   (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
2486 			return -EIO;
2487 
2488 		cmd &= ~PCI_X_CMD_MAX_READ;
2489 		cmd |= v << 2;
2490 		err = pci_write_config_dword(dev, cap + PCI_X_CMD, cmd);
2491 	}
2492 out:
2493 	return err;
2494 }
2495 EXPORT_SYMBOL(pcix_set_mmrbc);
2496 
2497 /**
2498  * pcie_get_readrq - get PCI Express read request size
2499  * @dev: PCI device to query
2500  *
2501  * Returns maximum memory read request in bytes
2502  *    or appropriate error value.
2503  */
2504 int pcie_get_readrq(struct pci_dev *dev)
2505 {
2506 	int ret, cap;
2507 	u16 ctl;
2508 
2509 	cap = pci_pcie_cap(dev);
2510 	if (!cap)
2511 		return -EINVAL;
2512 
2513 	ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
2514 	if (!ret)
2515 	ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
2516 
2517 	return ret;
2518 }
2519 EXPORT_SYMBOL(pcie_get_readrq);
2520 
2521 /**
2522  * pcie_set_readrq - set PCI Express maximum memory read request
2523  * @dev: PCI device to query
2524  * @rq: maximum memory read count in bytes
2525  *    valid values are 128, 256, 512, 1024, 2048, 4096
2526  *
2527  * If possible sets maximum read byte count
2528  */
2529 int pcie_set_readrq(struct pci_dev *dev, int rq)
2530 {
2531 	int cap, err = -EINVAL;
2532 	u16 ctl, v;
2533 
2534 	if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
2535 		goto out;
2536 
2537 	v = (ffs(rq) - 8) << 12;
2538 
2539 	cap = pci_pcie_cap(dev);
2540 	if (!cap)
2541 		goto out;
2542 
2543 	err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
2544 	if (err)
2545 		goto out;
2546 
2547 	if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
2548 		ctl &= ~PCI_EXP_DEVCTL_READRQ;
2549 		ctl |= v;
2550 		err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
2551 	}
2552 
2553 out:
2554 	return err;
2555 }
2556 EXPORT_SYMBOL(pcie_set_readrq);
2557 
2558 /**
2559  * pci_select_bars - Make BAR mask from the type of resource
2560  * @dev: the PCI device for which BAR mask is made
2561  * @flags: resource type mask to be selected
2562  *
2563  * This helper routine makes bar mask from the type of resource.
2564  */
2565 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
2566 {
2567 	int i, bars = 0;
2568 	for (i = 0; i < PCI_NUM_RESOURCES; i++)
2569 		if (pci_resource_flags(dev, i) & flags)
2570 			bars |= (1 << i);
2571 	return bars;
2572 }
2573 
2574 /**
2575  * pci_resource_bar - get position of the BAR associated with a resource
2576  * @dev: the PCI device
2577  * @resno: the resource number
2578  * @type: the BAR type to be filled in
2579  *
2580  * Returns BAR position in config space, or 0 if the BAR is invalid.
2581  */
2582 int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type)
2583 {
2584 	int reg;
2585 
2586 	if (resno < PCI_ROM_RESOURCE) {
2587 		*type = pci_bar_unknown;
2588 		return PCI_BASE_ADDRESS_0 + 4 * resno;
2589 	} else if (resno == PCI_ROM_RESOURCE) {
2590 		*type = pci_bar_mem32;
2591 		return dev->rom_base_reg;
2592 	} else if (resno < PCI_BRIDGE_RESOURCES) {
2593 		/* device specific resource */
2594 		reg = pci_iov_resource_bar(dev, resno, type);
2595 		if (reg)
2596 			return reg;
2597 	}
2598 
2599 	dev_err(&dev->dev, "BAR %d: invalid resource\n", resno);
2600 	return 0;
2601 }
2602 
2603 /**
2604  * pci_set_vga_state - set VGA decode state on device and parents if requested
2605  * @dev: the PCI device
2606  * @decode: true = enable decoding, false = disable decoding
2607  * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
2608  * @change_bridge: traverse ancestors and change bridges
2609  */
2610 int pci_set_vga_state(struct pci_dev *dev, bool decode,
2611 		      unsigned int command_bits, bool change_bridge)
2612 {
2613 	struct pci_bus *bus;
2614 	struct pci_dev *bridge;
2615 	u16 cmd;
2616 
2617 	WARN_ON(command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY));
2618 
2619 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2620 	if (decode == true)
2621 		cmd |= command_bits;
2622 	else
2623 		cmd &= ~command_bits;
2624 	pci_write_config_word(dev, PCI_COMMAND, cmd);
2625 
2626 	if (change_bridge == false)
2627 		return 0;
2628 
2629 	bus = dev->bus;
2630 	while (bus) {
2631 		bridge = bus->self;
2632 		if (bridge) {
2633 			pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
2634 					     &cmd);
2635 			if (decode == true)
2636 				cmd |= PCI_BRIDGE_CTL_VGA;
2637 			else
2638 				cmd &= ~PCI_BRIDGE_CTL_VGA;
2639 			pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
2640 					      cmd);
2641 		}
2642 		bus = bus->parent;
2643 	}
2644 	return 0;
2645 }
2646 
2647 #define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
2648 static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
2649 static DEFINE_SPINLOCK(resource_alignment_lock);
2650 
2651 /**
2652  * pci_specified_resource_alignment - get resource alignment specified by user.
2653  * @dev: the PCI device to get
2654  *
2655  * RETURNS: Resource alignment if it is specified.
2656  *          Zero if it is not specified.
2657  */
2658 resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
2659 {
2660 	int seg, bus, slot, func, align_order, count;
2661 	resource_size_t align = 0;
2662 	char *p;
2663 
2664 	spin_lock(&resource_alignment_lock);
2665 	p = resource_alignment_param;
2666 	while (*p) {
2667 		count = 0;
2668 		if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
2669 							p[count] == '@') {
2670 			p += count + 1;
2671 		} else {
2672 			align_order = -1;
2673 		}
2674 		if (sscanf(p, "%x:%x:%x.%x%n",
2675 			&seg, &bus, &slot, &func, &count) != 4) {
2676 			seg = 0;
2677 			if (sscanf(p, "%x:%x.%x%n",
2678 					&bus, &slot, &func, &count) != 3) {
2679 				/* Invalid format */
2680 				printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
2681 					p);
2682 				break;
2683 			}
2684 		}
2685 		p += count;
2686 		if (seg == pci_domain_nr(dev->bus) &&
2687 			bus == dev->bus->number &&
2688 			slot == PCI_SLOT(dev->devfn) &&
2689 			func == PCI_FUNC(dev->devfn)) {
2690 			if (align_order == -1) {
2691 				align = PAGE_SIZE;
2692 			} else {
2693 				align = 1 << align_order;
2694 			}
2695 			/* Found */
2696 			break;
2697 		}
2698 		if (*p != ';' && *p != ',') {
2699 			/* End of param or invalid format */
2700 			break;
2701 		}
2702 		p++;
2703 	}
2704 	spin_unlock(&resource_alignment_lock);
2705 	return align;
2706 }
2707 
2708 /**
2709  * pci_is_reassigndev - check if specified PCI is target device to reassign
2710  * @dev: the PCI device to check
2711  *
2712  * RETURNS: non-zero for PCI device is a target device to reassign,
2713  *          or zero is not.
2714  */
2715 int pci_is_reassigndev(struct pci_dev *dev)
2716 {
2717 	return (pci_specified_resource_alignment(dev) != 0);
2718 }
2719 
2720 ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
2721 {
2722 	if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
2723 		count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
2724 	spin_lock(&resource_alignment_lock);
2725 	strncpy(resource_alignment_param, buf, count);
2726 	resource_alignment_param[count] = '\0';
2727 	spin_unlock(&resource_alignment_lock);
2728 	return count;
2729 }
2730 
2731 ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
2732 {
2733 	size_t count;
2734 	spin_lock(&resource_alignment_lock);
2735 	count = snprintf(buf, size, "%s", resource_alignment_param);
2736 	spin_unlock(&resource_alignment_lock);
2737 	return count;
2738 }
2739 
2740 static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
2741 {
2742 	return pci_get_resource_alignment_param(buf, PAGE_SIZE);
2743 }
2744 
2745 static ssize_t pci_resource_alignment_store(struct bus_type *bus,
2746 					const char *buf, size_t count)
2747 {
2748 	return pci_set_resource_alignment_param(buf, count);
2749 }
2750 
2751 BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
2752 					pci_resource_alignment_store);
2753 
2754 static int __init pci_resource_alignment_sysfs_init(void)
2755 {
2756 	return bus_create_file(&pci_bus_type,
2757 					&bus_attr_resource_alignment);
2758 }
2759 
2760 late_initcall(pci_resource_alignment_sysfs_init);
2761 
2762 static void __devinit pci_no_domains(void)
2763 {
2764 #ifdef CONFIG_PCI_DOMAINS
2765 	pci_domains_supported = 0;
2766 #endif
2767 }
2768 
2769 /**
2770  * pci_ext_cfg_enabled - can we access extended PCI config space?
2771  * @dev: The PCI device of the root bridge.
2772  *
2773  * Returns 1 if we can access PCI extended config space (offsets
2774  * greater than 0xff). This is the default implementation. Architecture
2775  * implementations can override this.
2776  */
2777 int __attribute__ ((weak)) pci_ext_cfg_avail(struct pci_dev *dev)
2778 {
2779 	return 1;
2780 }
2781 
2782 static int __init pci_setup(char *str)
2783 {
2784 	while (str) {
2785 		char *k = strchr(str, ',');
2786 		if (k)
2787 			*k++ = 0;
2788 		if (*str && (str = pcibios_setup(str)) && *str) {
2789 			if (!strcmp(str, "nomsi")) {
2790 				pci_no_msi();
2791 			} else if (!strcmp(str, "noaer")) {
2792 				pci_no_aer();
2793 			} else if (!strcmp(str, "nodomains")) {
2794 				pci_no_domains();
2795 			} else if (!strncmp(str, "cbiosize=", 9)) {
2796 				pci_cardbus_io_size = memparse(str + 9, &str);
2797 			} else if (!strncmp(str, "cbmemsize=", 10)) {
2798 				pci_cardbus_mem_size = memparse(str + 10, &str);
2799 			} else if (!strncmp(str, "resource_alignment=", 19)) {
2800 				pci_set_resource_alignment_param(str + 19,
2801 							strlen(str + 19));
2802 			} else if (!strncmp(str, "ecrc=", 5)) {
2803 				pcie_ecrc_get_policy(str + 5);
2804 			} else if (!strncmp(str, "hpiosize=", 9)) {
2805 				pci_hotplug_io_size = memparse(str + 9, &str);
2806 			} else if (!strncmp(str, "hpmemsize=", 10)) {
2807 				pci_hotplug_mem_size = memparse(str + 10, &str);
2808 			} else {
2809 				printk(KERN_ERR "PCI: Unknown option `%s'\n",
2810 						str);
2811 			}
2812 		}
2813 		str = k;
2814 	}
2815 	return 0;
2816 }
2817 early_param("pci", pci_setup);
2818 
2819 EXPORT_SYMBOL(pci_reenable_device);
2820 EXPORT_SYMBOL(pci_enable_device_io);
2821 EXPORT_SYMBOL(pci_enable_device_mem);
2822 EXPORT_SYMBOL(pci_enable_device);
2823 EXPORT_SYMBOL(pcim_enable_device);
2824 EXPORT_SYMBOL(pcim_pin_device);
2825 EXPORT_SYMBOL(pci_disable_device);
2826 EXPORT_SYMBOL(pci_find_capability);
2827 EXPORT_SYMBOL(pci_bus_find_capability);
2828 EXPORT_SYMBOL(pci_release_regions);
2829 EXPORT_SYMBOL(pci_request_regions);
2830 EXPORT_SYMBOL(pci_request_regions_exclusive);
2831 EXPORT_SYMBOL(pci_release_region);
2832 EXPORT_SYMBOL(pci_request_region);
2833 EXPORT_SYMBOL(pci_request_region_exclusive);
2834 EXPORT_SYMBOL(pci_release_selected_regions);
2835 EXPORT_SYMBOL(pci_request_selected_regions);
2836 EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
2837 EXPORT_SYMBOL(pci_set_master);
2838 EXPORT_SYMBOL(pci_clear_master);
2839 EXPORT_SYMBOL(pci_set_mwi);
2840 EXPORT_SYMBOL(pci_try_set_mwi);
2841 EXPORT_SYMBOL(pci_clear_mwi);
2842 EXPORT_SYMBOL_GPL(pci_intx);
2843 EXPORT_SYMBOL(pci_set_dma_mask);
2844 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
2845 EXPORT_SYMBOL(pci_assign_resource);
2846 EXPORT_SYMBOL(pci_find_parent_resource);
2847 EXPORT_SYMBOL(pci_select_bars);
2848 
2849 EXPORT_SYMBOL(pci_set_power_state);
2850 EXPORT_SYMBOL(pci_save_state);
2851 EXPORT_SYMBOL(pci_restore_state);
2852 EXPORT_SYMBOL(pci_pme_capable);
2853 EXPORT_SYMBOL(pci_pme_active);
2854 EXPORT_SYMBOL(pci_enable_wake);
2855 EXPORT_SYMBOL(pci_wake_from_d3);
2856 EXPORT_SYMBOL(pci_target_state);
2857 EXPORT_SYMBOL(pci_prepare_to_sleep);
2858 EXPORT_SYMBOL(pci_back_from_sleep);
2859 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
2860 
2861