xref: /linux/drivers/pci/pci.c (revision 42fda66387daa53538ae13a2c858396aaf037158)
1 /*
2  *	$Id: pci.c,v 1.91 1999/01/21 13:34:01 davem Exp $
3  *
4  *	PCI Bus Services, see include/linux/pci.h for further explanation.
5  *
6  *	Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
7  *	David Mosberger-Tang
8  *
9  *	Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/delay.h>
14 #include <linux/init.h>
15 #include <linux/pci.h>
16 #include <linux/pm.h>
17 #include <linux/module.h>
18 #include <linux/spinlock.h>
19 #include <linux/string.h>
20 #include <linux/log2.h>
21 #include <asm/dma.h>	/* isa_dma_bridge_buggy */
22 #include "pci.h"
23 
24 unsigned int pci_pm_d3_delay = 10;
25 
26 #ifdef CONFIG_PCI_DOMAINS
27 int pci_domains_supported = 1;
28 #endif
29 
30 #define DEFAULT_CARDBUS_IO_SIZE		(256)
31 #define DEFAULT_CARDBUS_MEM_SIZE	(64*1024*1024)
32 /* pci=cbmemsize=nnM,cbiosize=nn can override this */
33 unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
34 unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
35 
36 /**
37  * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
38  * @bus: pointer to PCI bus structure to search
39  *
40  * Given a PCI bus, returns the highest PCI bus number present in the set
41  * including the given PCI bus and its list of child PCI buses.
42  */
43 unsigned char pci_bus_max_busnr(struct pci_bus* bus)
44 {
45 	struct list_head *tmp;
46 	unsigned char max, n;
47 
48 	max = bus->subordinate;
49 	list_for_each(tmp, &bus->children) {
50 		n = pci_bus_max_busnr(pci_bus_b(tmp));
51 		if(n > max)
52 			max = n;
53 	}
54 	return max;
55 }
56 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
57 
58 #if 0
59 /**
60  * pci_max_busnr - returns maximum PCI bus number
61  *
62  * Returns the highest PCI bus number present in the system global list of
63  * PCI buses.
64  */
65 unsigned char __devinit
66 pci_max_busnr(void)
67 {
68 	struct pci_bus *bus = NULL;
69 	unsigned char max, n;
70 
71 	max = 0;
72 	while ((bus = pci_find_next_bus(bus)) != NULL) {
73 		n = pci_bus_max_busnr(bus);
74 		if(n > max)
75 			max = n;
76 	}
77 	return max;
78 }
79 
80 #endif  /*  0  */
81 
82 #define PCI_FIND_CAP_TTL	48
83 
84 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
85 				   u8 pos, int cap, int *ttl)
86 {
87 	u8 id;
88 
89 	while ((*ttl)--) {
90 		pci_bus_read_config_byte(bus, devfn, pos, &pos);
91 		if (pos < 0x40)
92 			break;
93 		pos &= ~3;
94 		pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
95 					 &id);
96 		if (id == 0xff)
97 			break;
98 		if (id == cap)
99 			return pos;
100 		pos += PCI_CAP_LIST_NEXT;
101 	}
102 	return 0;
103 }
104 
105 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
106 			       u8 pos, int cap)
107 {
108 	int ttl = PCI_FIND_CAP_TTL;
109 
110 	return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
111 }
112 
113 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
114 {
115 	return __pci_find_next_cap(dev->bus, dev->devfn,
116 				   pos + PCI_CAP_LIST_NEXT, cap);
117 }
118 EXPORT_SYMBOL_GPL(pci_find_next_capability);
119 
120 static int __pci_bus_find_cap_start(struct pci_bus *bus,
121 				    unsigned int devfn, u8 hdr_type)
122 {
123 	u16 status;
124 
125 	pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
126 	if (!(status & PCI_STATUS_CAP_LIST))
127 		return 0;
128 
129 	switch (hdr_type) {
130 	case PCI_HEADER_TYPE_NORMAL:
131 	case PCI_HEADER_TYPE_BRIDGE:
132 		return PCI_CAPABILITY_LIST;
133 	case PCI_HEADER_TYPE_CARDBUS:
134 		return PCI_CB_CAPABILITY_LIST;
135 	default:
136 		return 0;
137 	}
138 
139 	return 0;
140 }
141 
142 /**
143  * pci_find_capability - query for devices' capabilities
144  * @dev: PCI device to query
145  * @cap: capability code
146  *
147  * Tell if a device supports a given PCI capability.
148  * Returns the address of the requested capability structure within the
149  * device's PCI configuration space or 0 in case the device does not
150  * support it.  Possible values for @cap:
151  *
152  *  %PCI_CAP_ID_PM           Power Management
153  *  %PCI_CAP_ID_AGP          Accelerated Graphics Port
154  *  %PCI_CAP_ID_VPD          Vital Product Data
155  *  %PCI_CAP_ID_SLOTID       Slot Identification
156  *  %PCI_CAP_ID_MSI          Message Signalled Interrupts
157  *  %PCI_CAP_ID_CHSWP        CompactPCI HotSwap
158  *  %PCI_CAP_ID_PCIX         PCI-X
159  *  %PCI_CAP_ID_EXP          PCI Express
160  */
161 int pci_find_capability(struct pci_dev *dev, int cap)
162 {
163 	int pos;
164 
165 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
166 	if (pos)
167 		pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
168 
169 	return pos;
170 }
171 
172 /**
173  * pci_bus_find_capability - query for devices' capabilities
174  * @bus:   the PCI bus to query
175  * @devfn: PCI device to query
176  * @cap:   capability code
177  *
178  * Like pci_find_capability() but works for pci devices that do not have a
179  * pci_dev structure set up yet.
180  *
181  * Returns the address of the requested capability structure within the
182  * device's PCI configuration space or 0 in case the device does not
183  * support it.
184  */
185 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
186 {
187 	int pos;
188 	u8 hdr_type;
189 
190 	pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
191 
192 	pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
193 	if (pos)
194 		pos = __pci_find_next_cap(bus, devfn, pos, cap);
195 
196 	return pos;
197 }
198 
199 /**
200  * pci_find_ext_capability - Find an extended capability
201  * @dev: PCI device to query
202  * @cap: capability code
203  *
204  * Returns the address of the requested extended capability structure
205  * within the device's PCI configuration space or 0 if the device does
206  * not support it.  Possible values for @cap:
207  *
208  *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
209  *  %PCI_EXT_CAP_ID_VC		Virtual Channel
210  *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
211  *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
212  */
213 int pci_find_ext_capability(struct pci_dev *dev, int cap)
214 {
215 	u32 header;
216 	int ttl = 480; /* 3840 bytes, minimum 8 bytes per capability */
217 	int pos = 0x100;
218 
219 	if (dev->cfg_size <= 256)
220 		return 0;
221 
222 	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
223 		return 0;
224 
225 	/*
226 	 * If we have no capabilities, this is indicated by cap ID,
227 	 * cap version and next pointer all being 0.
228 	 */
229 	if (header == 0)
230 		return 0;
231 
232 	while (ttl-- > 0) {
233 		if (PCI_EXT_CAP_ID(header) == cap)
234 			return pos;
235 
236 		pos = PCI_EXT_CAP_NEXT(header);
237 		if (pos < 0x100)
238 			break;
239 
240 		if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
241 			break;
242 	}
243 
244 	return 0;
245 }
246 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
247 
248 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
249 {
250 	int rc, ttl = PCI_FIND_CAP_TTL;
251 	u8 cap, mask;
252 
253 	if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
254 		mask = HT_3BIT_CAP_MASK;
255 	else
256 		mask = HT_5BIT_CAP_MASK;
257 
258 	pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
259 				      PCI_CAP_ID_HT, &ttl);
260 	while (pos) {
261 		rc = pci_read_config_byte(dev, pos + 3, &cap);
262 		if (rc != PCIBIOS_SUCCESSFUL)
263 			return 0;
264 
265 		if ((cap & mask) == ht_cap)
266 			return pos;
267 
268 		pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
269 					      pos + PCI_CAP_LIST_NEXT,
270 					      PCI_CAP_ID_HT, &ttl);
271 	}
272 
273 	return 0;
274 }
275 /**
276  * pci_find_next_ht_capability - query a device's Hypertransport capabilities
277  * @dev: PCI device to query
278  * @pos: Position from which to continue searching
279  * @ht_cap: Hypertransport capability code
280  *
281  * To be used in conjunction with pci_find_ht_capability() to search for
282  * all capabilities matching @ht_cap. @pos should always be a value returned
283  * from pci_find_ht_capability().
284  *
285  * NB. To be 100% safe against broken PCI devices, the caller should take
286  * steps to avoid an infinite loop.
287  */
288 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
289 {
290 	return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
291 }
292 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
293 
294 /**
295  * pci_find_ht_capability - query a device's Hypertransport capabilities
296  * @dev: PCI device to query
297  * @ht_cap: Hypertransport capability code
298  *
299  * Tell if a device supports a given Hypertransport capability.
300  * Returns an address within the device's PCI configuration space
301  * or 0 in case the device does not support the request capability.
302  * The address points to the PCI capability, of type PCI_CAP_ID_HT,
303  * which has a Hypertransport capability matching @ht_cap.
304  */
305 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
306 {
307 	int pos;
308 
309 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
310 	if (pos)
311 		pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
312 
313 	return pos;
314 }
315 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
316 
317 /**
318  * pci_find_parent_resource - return resource region of parent bus of given region
319  * @dev: PCI device structure contains resources to be searched
320  * @res: child resource record for which parent is sought
321  *
322  *  For given resource region of given device, return the resource
323  *  region of parent bus the given region is contained in or where
324  *  it should be allocated from.
325  */
326 struct resource *
327 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
328 {
329 	const struct pci_bus *bus = dev->bus;
330 	int i;
331 	struct resource *best = NULL;
332 
333 	for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
334 		struct resource *r = bus->resource[i];
335 		if (!r)
336 			continue;
337 		if (res->start && !(res->start >= r->start && res->end <= r->end))
338 			continue;	/* Not contained */
339 		if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
340 			continue;	/* Wrong type */
341 		if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
342 			return r;	/* Exact match */
343 		if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
344 			best = r;	/* Approximating prefetchable by non-prefetchable */
345 	}
346 	return best;
347 }
348 
349 /**
350  * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
351  * @dev: PCI device to have its BARs restored
352  *
353  * Restore the BAR values for a given device, so as to make it
354  * accessible by its driver.
355  */
356 void
357 pci_restore_bars(struct pci_dev *dev)
358 {
359 	int i, numres;
360 
361 	switch (dev->hdr_type) {
362 	case PCI_HEADER_TYPE_NORMAL:
363 		numres = 6;
364 		break;
365 	case PCI_HEADER_TYPE_BRIDGE:
366 		numres = 2;
367 		break;
368 	case PCI_HEADER_TYPE_CARDBUS:
369 		numres = 1;
370 		break;
371 	default:
372 		/* Should never get here, but just in case... */
373 		return;
374 	}
375 
376 	for (i = 0; i < numres; i ++)
377 		pci_update_resource(dev, &dev->resource[i], i);
378 }
379 
380 int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t t);
381 
382 /**
383  * pci_set_power_state - Set the power state of a PCI device
384  * @dev: PCI device to be suspended
385  * @state: PCI power state (D0, D1, D2, D3hot, D3cold) we're entering
386  *
387  * Transition a device to a new power state, using the Power Management
388  * Capabilities in the device's config space.
389  *
390  * RETURN VALUE:
391  * -EINVAL if trying to enter a lower state than we're already in.
392  * 0 if we're already in the requested state.
393  * -EIO if device does not support PCI PM.
394  * 0 if we can successfully change the power state.
395  */
396 int
397 pci_set_power_state(struct pci_dev *dev, pci_power_t state)
398 {
399 	int pm, need_restore = 0;
400 	u16 pmcsr, pmc;
401 
402 	/* bound the state we're entering */
403 	if (state > PCI_D3hot)
404 		state = PCI_D3hot;
405 
406 	/*
407 	 * If the device or the parent bridge can't support PCI PM, ignore
408 	 * the request if we're doing anything besides putting it into D0
409 	 * (which would only happen on boot).
410 	 */
411 	if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
412 		return 0;
413 
414 	/* find PCI PM capability in list */
415 	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
416 
417 	/* abort if the device doesn't support PM capabilities */
418 	if (!pm)
419 		return -EIO;
420 
421 	/* Validate current state:
422 	 * Can enter D0 from any state, but if we can only go deeper
423 	 * to sleep if we're already in a low power state
424 	 */
425 	if (state != PCI_D0 && dev->current_state > state) {
426 		printk(KERN_ERR "%s(): %s: state=%d, current state=%d\n",
427 			__FUNCTION__, pci_name(dev), state, dev->current_state);
428 		return -EINVAL;
429 	} else if (dev->current_state == state)
430 		return 0;        /* we're already there */
431 
432 
433 	pci_read_config_word(dev,pm + PCI_PM_PMC,&pmc);
434 	if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
435 		printk(KERN_DEBUG
436 		       "PCI: %s has unsupported PM cap regs version (%u)\n",
437 		       pci_name(dev), pmc & PCI_PM_CAP_VER_MASK);
438 		return -EIO;
439 	}
440 
441 	/* check if this device supports the desired state */
442 	if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
443 		return -EIO;
444 	else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2))
445 		return -EIO;
446 
447 	pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
448 
449 	/* If we're (effectively) in D3, force entire word to 0.
450 	 * This doesn't affect PME_Status, disables PME_En, and
451 	 * sets PowerState to 0.
452 	 */
453 	switch (dev->current_state) {
454 	case PCI_D0:
455 	case PCI_D1:
456 	case PCI_D2:
457 		pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
458 		pmcsr |= state;
459 		break;
460 	case PCI_UNKNOWN: /* Boot-up */
461 		if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
462 		 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
463 			need_restore = 1;
464 		/* Fall-through: force to D0 */
465 	default:
466 		pmcsr = 0;
467 		break;
468 	}
469 
470 	/* enter specified state */
471 	pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
472 
473 	/* Mandatory power management transition delays */
474 	/* see PCI PM 1.1 5.6.1 table 18 */
475 	if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
476 		msleep(pci_pm_d3_delay);
477 	else if (state == PCI_D2 || dev->current_state == PCI_D2)
478 		udelay(200);
479 
480 	/*
481 	 * Give firmware a chance to be called, such as ACPI _PRx, _PSx
482 	 * Firmware method after native method ?
483 	 */
484 	if (platform_pci_set_power_state)
485 		platform_pci_set_power_state(dev, state);
486 
487 	dev->current_state = state;
488 
489 	/* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
490 	 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
491 	 * from D3hot to D0 _may_ perform an internal reset, thereby
492 	 * going to "D0 Uninitialized" rather than "D0 Initialized".
493 	 * For example, at least some versions of the 3c905B and the
494 	 * 3c556B exhibit this behaviour.
495 	 *
496 	 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
497 	 * devices in a D3hot state at boot.  Consequently, we need to
498 	 * restore at least the BARs so that the device will be
499 	 * accessible to its driver.
500 	 */
501 	if (need_restore)
502 		pci_restore_bars(dev);
503 
504 	return 0;
505 }
506 
507 pci_power_t (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
508 
509 /**
510  * pci_choose_state - Choose the power state of a PCI device
511  * @dev: PCI device to be suspended
512  * @state: target sleep state for the whole system. This is the value
513  *	that is passed to suspend() function.
514  *
515  * Returns PCI power state suitable for given device and given system
516  * message.
517  */
518 
519 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
520 {
521 	pci_power_t ret;
522 
523 	if (!pci_find_capability(dev, PCI_CAP_ID_PM))
524 		return PCI_D0;
525 
526 	if (platform_pci_choose_state) {
527 		ret = platform_pci_choose_state(dev, state);
528 		if (ret != PCI_POWER_ERROR)
529 			return ret;
530 	}
531 
532 	switch (state.event) {
533 	case PM_EVENT_ON:
534 		return PCI_D0;
535 	case PM_EVENT_FREEZE:
536 	case PM_EVENT_PRETHAW:
537 		/* REVISIT both freeze and pre-thaw "should" use D0 */
538 	case PM_EVENT_SUSPEND:
539 		return PCI_D3hot;
540 	default:
541 		printk("Unrecognized suspend event %d\n", state.event);
542 		BUG();
543 	}
544 	return PCI_D0;
545 }
546 
547 EXPORT_SYMBOL(pci_choose_state);
548 
549 static int pci_save_pcie_state(struct pci_dev *dev)
550 {
551 	int pos, i = 0;
552 	struct pci_cap_saved_state *save_state;
553 	u16 *cap;
554 
555 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
556 	if (pos <= 0)
557 		return 0;
558 
559 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
560 	if (!save_state)
561 		save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);
562 	if (!save_state) {
563 		dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
564 		return -ENOMEM;
565 	}
566 	cap = (u16 *)&save_state->data[0];
567 
568 	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
569 	pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
570 	pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
571 	pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
572 	pci_add_saved_cap(dev, save_state);
573 	return 0;
574 }
575 
576 static void pci_restore_pcie_state(struct pci_dev *dev)
577 {
578 	int i = 0, pos;
579 	struct pci_cap_saved_state *save_state;
580 	u16 *cap;
581 
582 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
583 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
584 	if (!save_state || pos <= 0)
585 		return;
586 	cap = (u16 *)&save_state->data[0];
587 
588 	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
589 	pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
590 	pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
591 	pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
592 }
593 
594 
595 static int pci_save_pcix_state(struct pci_dev *dev)
596 {
597 	int pos, i = 0;
598 	struct pci_cap_saved_state *save_state;
599 	u16 *cap;
600 
601 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
602 	if (pos <= 0)
603 		return 0;
604 
605 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
606 	if (!save_state)
607 		save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);
608 	if (!save_state) {
609 		dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
610 		return -ENOMEM;
611 	}
612 	cap = (u16 *)&save_state->data[0];
613 
614 	pci_read_config_word(dev, pos + PCI_X_CMD, &cap[i++]);
615 	pci_add_saved_cap(dev, save_state);
616 	return 0;
617 }
618 
619 static void pci_restore_pcix_state(struct pci_dev *dev)
620 {
621 	int i = 0, pos;
622 	struct pci_cap_saved_state *save_state;
623 	u16 *cap;
624 
625 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
626 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
627 	if (!save_state || pos <= 0)
628 		return;
629 	cap = (u16 *)&save_state->data[0];
630 
631 	pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
632 }
633 
634 
635 /**
636  * pci_save_state - save the PCI configuration space of a device before suspending
637  * @dev: - PCI device that we're dealing with
638  */
639 int
640 pci_save_state(struct pci_dev *dev)
641 {
642 	int i;
643 	/* XXX: 100% dword access ok here? */
644 	for (i = 0; i < 16; i++)
645 		pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
646 	if ((i = pci_save_pcie_state(dev)) != 0)
647 		return i;
648 	if ((i = pci_save_pcix_state(dev)) != 0)
649 		return i;
650 	return 0;
651 }
652 
653 /**
654  * pci_restore_state - Restore the saved state of a PCI device
655  * @dev: - PCI device that we're dealing with
656  */
657 int
658 pci_restore_state(struct pci_dev *dev)
659 {
660 	int i;
661 	u32 val;
662 
663 	/* PCI Express register must be restored first */
664 	pci_restore_pcie_state(dev);
665 
666 	/*
667 	 * The Base Address register should be programmed before the command
668 	 * register(s)
669 	 */
670 	for (i = 15; i >= 0; i--) {
671 		pci_read_config_dword(dev, i * 4, &val);
672 		if (val != dev->saved_config_space[i]) {
673 			printk(KERN_DEBUG "PM: Writing back config space on "
674 				"device %s at offset %x (was %x, writing %x)\n",
675 				pci_name(dev), i,
676 				val, (int)dev->saved_config_space[i]);
677 			pci_write_config_dword(dev,i * 4,
678 				dev->saved_config_space[i]);
679 		}
680 	}
681 	pci_restore_pcix_state(dev);
682 	pci_restore_msi_state(dev);
683 
684 	return 0;
685 }
686 
687 static int do_pci_enable_device(struct pci_dev *dev, int bars)
688 {
689 	int err;
690 
691 	err = pci_set_power_state(dev, PCI_D0);
692 	if (err < 0 && err != -EIO)
693 		return err;
694 	err = pcibios_enable_device(dev, bars);
695 	if (err < 0)
696 		return err;
697 	pci_fixup_device(pci_fixup_enable, dev);
698 
699 	return 0;
700 }
701 
702 /**
703  * pci_reenable_device - Resume abandoned device
704  * @dev: PCI device to be resumed
705  *
706  *  Note this function is a backend of pci_default_resume and is not supposed
707  *  to be called by normal code, write proper resume handler and use it instead.
708  */
709 int pci_reenable_device(struct pci_dev *dev)
710 {
711 	if (atomic_read(&dev->enable_cnt))
712 		return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
713 	return 0;
714 }
715 
716 /**
717  * pci_enable_device_bars - Initialize some of a device for use
718  * @dev: PCI device to be initialized
719  * @bars: bitmask of BAR's that must be configured
720  *
721  *  Initialize device before it's used by a driver. Ask low-level code
722  *  to enable selected I/O and memory resources. Wake up the device if it
723  *  was suspended. Beware, this function can fail.
724  */
725 int
726 pci_enable_device_bars(struct pci_dev *dev, int bars)
727 {
728 	int err;
729 
730 	if (atomic_add_return(1, &dev->enable_cnt) > 1)
731 		return 0;		/* already enabled */
732 
733 	err = do_pci_enable_device(dev, bars);
734 	if (err < 0)
735 		atomic_dec(&dev->enable_cnt);
736 	return err;
737 }
738 
739 /**
740  * pci_enable_device - Initialize device before it's used by a driver.
741  * @dev: PCI device to be initialized
742  *
743  *  Initialize device before it's used by a driver. Ask low-level code
744  *  to enable I/O and memory. Wake up the device if it was suspended.
745  *  Beware, this function can fail.
746  *
747  *  Note we don't actually enable the device many times if we call
748  *  this function repeatedly (we just increment the count).
749  */
750 int pci_enable_device(struct pci_dev *dev)
751 {
752 	return pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
753 }
754 
755 /*
756  * Managed PCI resources.  This manages device on/off, intx/msi/msix
757  * on/off and BAR regions.  pci_dev itself records msi/msix status, so
758  * there's no need to track it separately.  pci_devres is initialized
759  * when a device is enabled using managed PCI device enable interface.
760  */
761 struct pci_devres {
762 	unsigned int enabled:1;
763 	unsigned int pinned:1;
764 	unsigned int orig_intx:1;
765 	unsigned int restore_intx:1;
766 	u32 region_mask;
767 };
768 
769 static void pcim_release(struct device *gendev, void *res)
770 {
771 	struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
772 	struct pci_devres *this = res;
773 	int i;
774 
775 	if (dev->msi_enabled)
776 		pci_disable_msi(dev);
777 	if (dev->msix_enabled)
778 		pci_disable_msix(dev);
779 
780 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
781 		if (this->region_mask & (1 << i))
782 			pci_release_region(dev, i);
783 
784 	if (this->restore_intx)
785 		pci_intx(dev, this->orig_intx);
786 
787 	if (this->enabled && !this->pinned)
788 		pci_disable_device(dev);
789 }
790 
791 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
792 {
793 	struct pci_devres *dr, *new_dr;
794 
795 	dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
796 	if (dr)
797 		return dr;
798 
799 	new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
800 	if (!new_dr)
801 		return NULL;
802 	return devres_get(&pdev->dev, new_dr, NULL, NULL);
803 }
804 
805 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
806 {
807 	if (pci_is_managed(pdev))
808 		return devres_find(&pdev->dev, pcim_release, NULL, NULL);
809 	return NULL;
810 }
811 
812 /**
813  * pcim_enable_device - Managed pci_enable_device()
814  * @pdev: PCI device to be initialized
815  *
816  * Managed pci_enable_device().
817  */
818 int pcim_enable_device(struct pci_dev *pdev)
819 {
820 	struct pci_devres *dr;
821 	int rc;
822 
823 	dr = get_pci_dr(pdev);
824 	if (unlikely(!dr))
825 		return -ENOMEM;
826 	WARN_ON(!!dr->enabled);
827 
828 	rc = pci_enable_device(pdev);
829 	if (!rc) {
830 		pdev->is_managed = 1;
831 		dr->enabled = 1;
832 	}
833 	return rc;
834 }
835 
836 /**
837  * pcim_pin_device - Pin managed PCI device
838  * @pdev: PCI device to pin
839  *
840  * Pin managed PCI device @pdev.  Pinned device won't be disabled on
841  * driver detach.  @pdev must have been enabled with
842  * pcim_enable_device().
843  */
844 void pcim_pin_device(struct pci_dev *pdev)
845 {
846 	struct pci_devres *dr;
847 
848 	dr = find_pci_dr(pdev);
849 	WARN_ON(!dr || !dr->enabled);
850 	if (dr)
851 		dr->pinned = 1;
852 }
853 
854 /**
855  * pcibios_disable_device - disable arch specific PCI resources for device dev
856  * @dev: the PCI device to disable
857  *
858  * Disables architecture specific PCI resources for the device. This
859  * is the default implementation. Architecture implementations can
860  * override this.
861  */
862 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
863 
864 /**
865  * pci_disable_device - Disable PCI device after use
866  * @dev: PCI device to be disabled
867  *
868  * Signal to the system that the PCI device is not in use by the system
869  * anymore.  This only involves disabling PCI bus-mastering, if active.
870  *
871  * Note we don't actually disable the device until all callers of
872  * pci_device_enable() have called pci_device_disable().
873  */
874 void
875 pci_disable_device(struct pci_dev *dev)
876 {
877 	struct pci_devres *dr;
878 	u16 pci_command;
879 
880 	dr = find_pci_dr(dev);
881 	if (dr)
882 		dr->enabled = 0;
883 
884 	if (atomic_sub_return(1, &dev->enable_cnt) != 0)
885 		return;
886 
887 	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
888 	if (pci_command & PCI_COMMAND_MASTER) {
889 		pci_command &= ~PCI_COMMAND_MASTER;
890 		pci_write_config_word(dev, PCI_COMMAND, pci_command);
891 	}
892 	dev->is_busmaster = 0;
893 
894 	pcibios_disable_device(dev);
895 }
896 
897 /**
898  * pcibios_set_pcie_reset_state - set reset state for device dev
899  * @dev: the PCI-E device reset
900  * @state: Reset state to enter into
901  *
902  *
903  * Sets the PCI-E reset state for the device. This is the default
904  * implementation. Architecture implementations can override this.
905  */
906 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
907 							enum pcie_reset_state state)
908 {
909 	return -EINVAL;
910 }
911 
912 /**
913  * pci_set_pcie_reset_state - set reset state for device dev
914  * @dev: the PCI-E device reset
915  * @state: Reset state to enter into
916  *
917  *
918  * Sets the PCI reset state for the device.
919  */
920 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
921 {
922 	return pcibios_set_pcie_reset_state(dev, state);
923 }
924 
925 /**
926  * pci_enable_wake - enable PCI device as wakeup event source
927  * @dev: PCI device affected
928  * @state: PCI state from which device will issue wakeup events
929  * @enable: True to enable event generation; false to disable
930  *
931  * This enables the device as a wakeup event source, or disables it.
932  * When such events involves platform-specific hooks, those hooks are
933  * called automatically by this routine.
934  *
935  * Devices with legacy power management (no standard PCI PM capabilities)
936  * always require such platform hooks.  Depending on the platform, devices
937  * supporting the standard PCI PME# signal may require such platform hooks;
938  * they always update bits in config space to allow PME# generation.
939  *
940  * -EIO is returned if the device can't ever be a wakeup event source.
941  * -EINVAL is returned if the device can't generate wakeup events from
942  * the specified PCI state.  Returns zero if the operation is successful.
943  */
944 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
945 {
946 	int pm;
947 	int status;
948 	u16 value;
949 
950 	/* Note that drivers should verify device_may_wakeup(&dev->dev)
951 	 * before calling this function.  Platform code should report
952 	 * errors when drivers try to enable wakeup on devices that
953 	 * can't issue wakeups, or on which wakeups were disabled by
954 	 * userspace updating the /sys/devices.../power/wakeup file.
955 	 */
956 
957 	status = call_platform_enable_wakeup(&dev->dev, enable);
958 
959 	/* find PCI PM capability in list */
960 	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
961 
962 	/* If device doesn't support PM Capabilities, but caller wants to
963 	 * disable wake events, it's a NOP.  Otherwise fail unless the
964 	 * platform hooks handled this legacy device already.
965 	 */
966 	if (!pm)
967 		return enable ? status : 0;
968 
969 	/* Check device's ability to generate PME# */
970 	pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
971 
972 	value &= PCI_PM_CAP_PME_MASK;
973 	value >>= ffs(PCI_PM_CAP_PME_MASK) - 1;   /* First bit of mask */
974 
975 	/* Check if it can generate PME# from requested state. */
976 	if (!value || !(value & (1 << state))) {
977 		/* if it can't, revert what the platform hook changed,
978 		 * always reporting the base "EINVAL, can't PME#" error
979 		 */
980 		if (enable)
981 			call_platform_enable_wakeup(&dev->dev, 0);
982 		return enable ? -EINVAL : 0;
983 	}
984 
985 	pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
986 
987 	/* Clear PME_Status by writing 1 to it and enable PME# */
988 	value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
989 
990 	if (!enable)
991 		value &= ~PCI_PM_CTRL_PME_ENABLE;
992 
993 	pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
994 
995 	return 0;
996 }
997 
998 int
999 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
1000 {
1001 	u8 pin;
1002 
1003 	pin = dev->pin;
1004 	if (!pin)
1005 		return -1;
1006 	pin--;
1007 	while (dev->bus->self) {
1008 		pin = (pin + PCI_SLOT(dev->devfn)) % 4;
1009 		dev = dev->bus->self;
1010 	}
1011 	*bridge = dev;
1012 	return pin;
1013 }
1014 
1015 /**
1016  *	pci_release_region - Release a PCI bar
1017  *	@pdev: PCI device whose resources were previously reserved by pci_request_region
1018  *	@bar: BAR to release
1019  *
1020  *	Releases the PCI I/O and memory resources previously reserved by a
1021  *	successful call to pci_request_region.  Call this function only
1022  *	after all use of the PCI regions has ceased.
1023  */
1024 void pci_release_region(struct pci_dev *pdev, int bar)
1025 {
1026 	struct pci_devres *dr;
1027 
1028 	if (pci_resource_len(pdev, bar) == 0)
1029 		return;
1030 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1031 		release_region(pci_resource_start(pdev, bar),
1032 				pci_resource_len(pdev, bar));
1033 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1034 		release_mem_region(pci_resource_start(pdev, bar),
1035 				pci_resource_len(pdev, bar));
1036 
1037 	dr = find_pci_dr(pdev);
1038 	if (dr)
1039 		dr->region_mask &= ~(1 << bar);
1040 }
1041 
1042 /**
1043  *	pci_request_region - Reserved PCI I/O and memory resource
1044  *	@pdev: PCI device whose resources are to be reserved
1045  *	@bar: BAR to be reserved
1046  *	@res_name: Name to be associated with resource.
1047  *
1048  *	Mark the PCI region associated with PCI device @pdev BR @bar as
1049  *	being reserved by owner @res_name.  Do not access any
1050  *	address inside the PCI regions unless this call returns
1051  *	successfully.
1052  *
1053  *	Returns 0 on success, or %EBUSY on error.  A warning
1054  *	message is also printed on failure.
1055  */
1056 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1057 {
1058 	struct pci_devres *dr;
1059 
1060 	if (pci_resource_len(pdev, bar) == 0)
1061 		return 0;
1062 
1063 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1064 		if (!request_region(pci_resource_start(pdev, bar),
1065 			    pci_resource_len(pdev, bar), res_name))
1066 			goto err_out;
1067 	}
1068 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1069 		if (!request_mem_region(pci_resource_start(pdev, bar),
1070 				        pci_resource_len(pdev, bar), res_name))
1071 			goto err_out;
1072 	}
1073 
1074 	dr = find_pci_dr(pdev);
1075 	if (dr)
1076 		dr->region_mask |= 1 << bar;
1077 
1078 	return 0;
1079 
1080 err_out:
1081 	printk (KERN_WARNING "PCI: Unable to reserve %s region #%d:%llx@%llx "
1082 		"for device %s\n",
1083 		pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
1084 		bar + 1, /* PCI BAR # */
1085 		(unsigned long long)pci_resource_len(pdev, bar),
1086 		(unsigned long long)pci_resource_start(pdev, bar),
1087 		pci_name(pdev));
1088 	return -EBUSY;
1089 }
1090 
1091 /**
1092  * pci_release_selected_regions - Release selected PCI I/O and memory resources
1093  * @pdev: PCI device whose resources were previously reserved
1094  * @bars: Bitmask of BARs to be released
1095  *
1096  * Release selected PCI I/O and memory resources previously reserved.
1097  * Call this function only after all use of the PCI regions has ceased.
1098  */
1099 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1100 {
1101 	int i;
1102 
1103 	for (i = 0; i < 6; i++)
1104 		if (bars & (1 << i))
1105 			pci_release_region(pdev, i);
1106 }
1107 
1108 /**
1109  * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
1110  * @pdev: PCI device whose resources are to be reserved
1111  * @bars: Bitmask of BARs to be requested
1112  * @res_name: Name to be associated with resource
1113  */
1114 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
1115 				 const char *res_name)
1116 {
1117 	int i;
1118 
1119 	for (i = 0; i < 6; i++)
1120 		if (bars & (1 << i))
1121 			if(pci_request_region(pdev, i, res_name))
1122 				goto err_out;
1123 	return 0;
1124 
1125 err_out:
1126 	while(--i >= 0)
1127 		if (bars & (1 << i))
1128 			pci_release_region(pdev, i);
1129 
1130 	return -EBUSY;
1131 }
1132 
1133 /**
1134  *	pci_release_regions - Release reserved PCI I/O and memory resources
1135  *	@pdev: PCI device whose resources were previously reserved by pci_request_regions
1136  *
1137  *	Releases all PCI I/O and memory resources previously reserved by a
1138  *	successful call to pci_request_regions.  Call this function only
1139  *	after all use of the PCI regions has ceased.
1140  */
1141 
1142 void pci_release_regions(struct pci_dev *pdev)
1143 {
1144 	pci_release_selected_regions(pdev, (1 << 6) - 1);
1145 }
1146 
1147 /**
1148  *	pci_request_regions - Reserved PCI I/O and memory resources
1149  *	@pdev: PCI device whose resources are to be reserved
1150  *	@res_name: Name to be associated with resource.
1151  *
1152  *	Mark all PCI regions associated with PCI device @pdev as
1153  *	being reserved by owner @res_name.  Do not access any
1154  *	address inside the PCI regions unless this call returns
1155  *	successfully.
1156  *
1157  *	Returns 0 on success, or %EBUSY on error.  A warning
1158  *	message is also printed on failure.
1159  */
1160 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
1161 {
1162 	return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
1163 }
1164 
1165 /**
1166  * pci_set_master - enables bus-mastering for device dev
1167  * @dev: the PCI device to enable
1168  *
1169  * Enables bus-mastering on the device and calls pcibios_set_master()
1170  * to do the needed arch specific settings.
1171  */
1172 void
1173 pci_set_master(struct pci_dev *dev)
1174 {
1175 	u16 cmd;
1176 
1177 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1178 	if (! (cmd & PCI_COMMAND_MASTER)) {
1179 		pr_debug("PCI: Enabling bus mastering for device %s\n", pci_name(dev));
1180 		cmd |= PCI_COMMAND_MASTER;
1181 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1182 	}
1183 	dev->is_busmaster = 1;
1184 	pcibios_set_master(dev);
1185 }
1186 
1187 #ifdef PCI_DISABLE_MWI
1188 int pci_set_mwi(struct pci_dev *dev)
1189 {
1190 	return 0;
1191 }
1192 
1193 int pci_try_set_mwi(struct pci_dev *dev)
1194 {
1195 	return 0;
1196 }
1197 
1198 void pci_clear_mwi(struct pci_dev *dev)
1199 {
1200 }
1201 
1202 #else
1203 
1204 #ifndef PCI_CACHE_LINE_BYTES
1205 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
1206 #endif
1207 
1208 /* This can be overridden by arch code. */
1209 /* Don't forget this is measured in 32-bit words, not bytes */
1210 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
1211 
1212 /**
1213  * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1214  * @dev: the PCI device for which MWI is to be enabled
1215  *
1216  * Helper function for pci_set_mwi.
1217  * Originally copied from drivers/net/acenic.c.
1218  * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1219  *
1220  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1221  */
1222 static int
1223 pci_set_cacheline_size(struct pci_dev *dev)
1224 {
1225 	u8 cacheline_size;
1226 
1227 	if (!pci_cache_line_size)
1228 		return -EINVAL;		/* The system doesn't support MWI. */
1229 
1230 	/* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1231 	   equal to or multiple of the right value. */
1232 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1233 	if (cacheline_size >= pci_cache_line_size &&
1234 	    (cacheline_size % pci_cache_line_size) == 0)
1235 		return 0;
1236 
1237 	/* Write the correct value. */
1238 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1239 	/* Read it back. */
1240 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1241 	if (cacheline_size == pci_cache_line_size)
1242 		return 0;
1243 
1244 	printk(KERN_DEBUG "PCI: cache line size of %d is not supported "
1245 	       "by device %s\n", pci_cache_line_size << 2, pci_name(dev));
1246 
1247 	return -EINVAL;
1248 }
1249 
1250 /**
1251  * pci_set_mwi - enables memory-write-invalidate PCI transaction
1252  * @dev: the PCI device for which MWI is enabled
1253  *
1254  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1255  *
1256  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1257  */
1258 int
1259 pci_set_mwi(struct pci_dev *dev)
1260 {
1261 	int rc;
1262 	u16 cmd;
1263 
1264 	rc = pci_set_cacheline_size(dev);
1265 	if (rc)
1266 		return rc;
1267 
1268 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1269 	if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1270 		pr_debug("PCI: Enabling Mem-Wr-Inval for device %s\n",
1271 			pci_name(dev));
1272 		cmd |= PCI_COMMAND_INVALIDATE;
1273 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1274 	}
1275 
1276 	return 0;
1277 }
1278 
1279 /**
1280  * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
1281  * @dev: the PCI device for which MWI is enabled
1282  *
1283  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1284  * Callers are not required to check the return value.
1285  *
1286  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1287  */
1288 int pci_try_set_mwi(struct pci_dev *dev)
1289 {
1290 	int rc = pci_set_mwi(dev);
1291 	return rc;
1292 }
1293 
1294 /**
1295  * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1296  * @dev: the PCI device to disable
1297  *
1298  * Disables PCI Memory-Write-Invalidate transaction on the device
1299  */
1300 void
1301 pci_clear_mwi(struct pci_dev *dev)
1302 {
1303 	u16 cmd;
1304 
1305 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1306 	if (cmd & PCI_COMMAND_INVALIDATE) {
1307 		cmd &= ~PCI_COMMAND_INVALIDATE;
1308 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1309 	}
1310 }
1311 #endif /* ! PCI_DISABLE_MWI */
1312 
1313 /**
1314  * pci_intx - enables/disables PCI INTx for device dev
1315  * @pdev: the PCI device to operate on
1316  * @enable: boolean: whether to enable or disable PCI INTx
1317  *
1318  * Enables/disables PCI INTx for device dev
1319  */
1320 void
1321 pci_intx(struct pci_dev *pdev, int enable)
1322 {
1323 	u16 pci_command, new;
1324 
1325 	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1326 
1327 	if (enable) {
1328 		new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1329 	} else {
1330 		new = pci_command | PCI_COMMAND_INTX_DISABLE;
1331 	}
1332 
1333 	if (new != pci_command) {
1334 		struct pci_devres *dr;
1335 
1336 		pci_write_config_word(pdev, PCI_COMMAND, new);
1337 
1338 		dr = find_pci_dr(pdev);
1339 		if (dr && !dr->restore_intx) {
1340 			dr->restore_intx = 1;
1341 			dr->orig_intx = !enable;
1342 		}
1343 	}
1344 }
1345 
1346 /**
1347  * pci_msi_off - disables any msi or msix capabilities
1348  * @dev: the PCI device to operate on
1349  *
1350  * If you want to use msi see pci_enable_msi and friends.
1351  * This is a lower level primitive that allows us to disable
1352  * msi operation at the device level.
1353  */
1354 void pci_msi_off(struct pci_dev *dev)
1355 {
1356 	int pos;
1357 	u16 control;
1358 
1359 	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
1360 	if (pos) {
1361 		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
1362 		control &= ~PCI_MSI_FLAGS_ENABLE;
1363 		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
1364 	}
1365 	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1366 	if (pos) {
1367 		pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
1368 		control &= ~PCI_MSIX_FLAGS_ENABLE;
1369 		pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
1370 	}
1371 }
1372 
1373 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
1374 /*
1375  * These can be overridden by arch-specific implementations
1376  */
1377 int
1378 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
1379 {
1380 	if (!pci_dma_supported(dev, mask))
1381 		return -EIO;
1382 
1383 	dev->dma_mask = mask;
1384 
1385 	return 0;
1386 }
1387 
1388 int
1389 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
1390 {
1391 	if (!pci_dma_supported(dev, mask))
1392 		return -EIO;
1393 
1394 	dev->dev.coherent_dma_mask = mask;
1395 
1396 	return 0;
1397 }
1398 #endif
1399 
1400 /**
1401  * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
1402  * @dev: PCI device to query
1403  *
1404  * Returns mmrbc: maximum designed memory read count in bytes
1405  *    or appropriate error value.
1406  */
1407 int pcix_get_max_mmrbc(struct pci_dev *dev)
1408 {
1409 	int err, cap;
1410 	u32 stat;
1411 
1412 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1413 	if (!cap)
1414 		return -EINVAL;
1415 
1416 	err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
1417 	if (err)
1418 		return -EINVAL;
1419 
1420 	return (stat & PCI_X_STATUS_MAX_READ) >> 12;
1421 }
1422 EXPORT_SYMBOL(pcix_get_max_mmrbc);
1423 
1424 /**
1425  * pcix_get_mmrbc - get PCI-X maximum memory read byte count
1426  * @dev: PCI device to query
1427  *
1428  * Returns mmrbc: maximum memory read count in bytes
1429  *    or appropriate error value.
1430  */
1431 int pcix_get_mmrbc(struct pci_dev *dev)
1432 {
1433 	int ret, cap;
1434 	u32 cmd;
1435 
1436 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1437 	if (!cap)
1438 		return -EINVAL;
1439 
1440 	ret = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
1441 	if (!ret)
1442 		ret = 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
1443 
1444 	return ret;
1445 }
1446 EXPORT_SYMBOL(pcix_get_mmrbc);
1447 
1448 /**
1449  * pcix_set_mmrbc - set PCI-X maximum memory read byte count
1450  * @dev: PCI device to query
1451  * @mmrbc: maximum memory read count in bytes
1452  *    valid values are 512, 1024, 2048, 4096
1453  *
1454  * If possible sets maximum memory read byte count, some bridges have erratas
1455  * that prevent this.
1456  */
1457 int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
1458 {
1459 	int cap, err = -EINVAL;
1460 	u32 stat, cmd, v, o;
1461 
1462 	if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
1463 		goto out;
1464 
1465 	v = ffs(mmrbc) - 10;
1466 
1467 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1468 	if (!cap)
1469 		goto out;
1470 
1471 	err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
1472 	if (err)
1473 		goto out;
1474 
1475 	if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
1476 		return -E2BIG;
1477 
1478 	err = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
1479 	if (err)
1480 		goto out;
1481 
1482 	o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
1483 	if (o != v) {
1484 		if (v > o && dev->bus &&
1485 		   (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
1486 			return -EIO;
1487 
1488 		cmd &= ~PCI_X_CMD_MAX_READ;
1489 		cmd |= v << 2;
1490 		err = pci_write_config_dword(dev, cap + PCI_X_CMD, cmd);
1491 	}
1492 out:
1493 	return err;
1494 }
1495 EXPORT_SYMBOL(pcix_set_mmrbc);
1496 
1497 /**
1498  * pcie_get_readrq - get PCI Express read request size
1499  * @dev: PCI device to query
1500  *
1501  * Returns maximum memory read request in bytes
1502  *    or appropriate error value.
1503  */
1504 int pcie_get_readrq(struct pci_dev *dev)
1505 {
1506 	int ret, cap;
1507 	u16 ctl;
1508 
1509 	cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
1510 	if (!cap)
1511 		return -EINVAL;
1512 
1513 	ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
1514 	if (!ret)
1515 	ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
1516 
1517 	return ret;
1518 }
1519 EXPORT_SYMBOL(pcie_get_readrq);
1520 
1521 /**
1522  * pcie_set_readrq - set PCI Express maximum memory read request
1523  * @dev: PCI device to query
1524  * @rq: maximum memory read count in bytes
1525  *    valid values are 128, 256, 512, 1024, 2048, 4096
1526  *
1527  * If possible sets maximum read byte count
1528  */
1529 int pcie_set_readrq(struct pci_dev *dev, int rq)
1530 {
1531 	int cap, err = -EINVAL;
1532 	u16 ctl, v;
1533 
1534 	if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
1535 		goto out;
1536 
1537 	v = (ffs(rq) - 8) << 12;
1538 
1539 	cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
1540 	if (!cap)
1541 		goto out;
1542 
1543 	err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
1544 	if (err)
1545 		goto out;
1546 
1547 	if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
1548 		ctl &= ~PCI_EXP_DEVCTL_READRQ;
1549 		ctl |= v;
1550 		err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
1551 	}
1552 
1553 out:
1554 	return err;
1555 }
1556 EXPORT_SYMBOL(pcie_set_readrq);
1557 
1558 /**
1559  * pci_select_bars - Make BAR mask from the type of resource
1560  * @dev: the PCI device for which BAR mask is made
1561  * @flags: resource type mask to be selected
1562  *
1563  * This helper routine makes bar mask from the type of resource.
1564  */
1565 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
1566 {
1567 	int i, bars = 0;
1568 	for (i = 0; i < PCI_NUM_RESOURCES; i++)
1569 		if (pci_resource_flags(dev, i) & flags)
1570 			bars |= (1 << i);
1571 	return bars;
1572 }
1573 
1574 static void __devinit pci_no_domains(void)
1575 {
1576 #ifdef CONFIG_PCI_DOMAINS
1577 	pci_domains_supported = 0;
1578 #endif
1579 }
1580 
1581 static int __devinit pci_init(void)
1582 {
1583 	struct pci_dev *dev = NULL;
1584 
1585 	while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
1586 		pci_fixup_device(pci_fixup_final, dev);
1587 	}
1588 	return 0;
1589 }
1590 
1591 static int __devinit pci_setup(char *str)
1592 {
1593 	while (str) {
1594 		char *k = strchr(str, ',');
1595 		if (k)
1596 			*k++ = 0;
1597 		if (*str && (str = pcibios_setup(str)) && *str) {
1598 			if (!strcmp(str, "nomsi")) {
1599 				pci_no_msi();
1600 			} else if (!strcmp(str, "noaer")) {
1601 				pci_no_aer();
1602 			} else if (!strcmp(str, "nodomains")) {
1603 				pci_no_domains();
1604 			} else if (!strncmp(str, "cbiosize=", 9)) {
1605 				pci_cardbus_io_size = memparse(str + 9, &str);
1606 			} else if (!strncmp(str, "cbmemsize=", 10)) {
1607 				pci_cardbus_mem_size = memparse(str + 10, &str);
1608 			} else {
1609 				printk(KERN_ERR "PCI: Unknown option `%s'\n",
1610 						str);
1611 			}
1612 		}
1613 		str = k;
1614 	}
1615 	return 0;
1616 }
1617 early_param("pci", pci_setup);
1618 
1619 device_initcall(pci_init);
1620 
1621 EXPORT_SYMBOL_GPL(pci_restore_bars);
1622 EXPORT_SYMBOL(pci_reenable_device);
1623 EXPORT_SYMBOL(pci_enable_device_bars);
1624 EXPORT_SYMBOL(pci_enable_device);
1625 EXPORT_SYMBOL(pcim_enable_device);
1626 EXPORT_SYMBOL(pcim_pin_device);
1627 EXPORT_SYMBOL(pci_disable_device);
1628 EXPORT_SYMBOL(pci_find_capability);
1629 EXPORT_SYMBOL(pci_bus_find_capability);
1630 EXPORT_SYMBOL(pci_release_regions);
1631 EXPORT_SYMBOL(pci_request_regions);
1632 EXPORT_SYMBOL(pci_release_region);
1633 EXPORT_SYMBOL(pci_request_region);
1634 EXPORT_SYMBOL(pci_release_selected_regions);
1635 EXPORT_SYMBOL(pci_request_selected_regions);
1636 EXPORT_SYMBOL(pci_set_master);
1637 EXPORT_SYMBOL(pci_set_mwi);
1638 EXPORT_SYMBOL(pci_try_set_mwi);
1639 EXPORT_SYMBOL(pci_clear_mwi);
1640 EXPORT_SYMBOL_GPL(pci_intx);
1641 EXPORT_SYMBOL(pci_set_dma_mask);
1642 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
1643 EXPORT_SYMBOL(pci_assign_resource);
1644 EXPORT_SYMBOL(pci_find_parent_resource);
1645 EXPORT_SYMBOL(pci_select_bars);
1646 
1647 EXPORT_SYMBOL(pci_set_power_state);
1648 EXPORT_SYMBOL(pci_save_state);
1649 EXPORT_SYMBOL(pci_restore_state);
1650 EXPORT_SYMBOL(pci_enable_wake);
1651 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
1652 
1653