xref: /openbmc/linux/drivers/pci/pci.c (revision c21b37f6)
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 <asm/dma.h>	/* isa_dma_bridge_buggy */
21 #include "pci.h"
22 
23 unsigned int pci_pm_d3_delay = 10;
24 
25 #define DEFAULT_CARDBUS_IO_SIZE		(256)
26 #define DEFAULT_CARDBUS_MEM_SIZE	(64*1024*1024)
27 /* pci=cbmemsize=nnM,cbiosize=nn can override this */
28 unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
29 unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
30 
31 /**
32  * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
33  * @bus: pointer to PCI bus structure to search
34  *
35  * Given a PCI bus, returns the highest PCI bus number present in the set
36  * including the given PCI bus and its list of child PCI buses.
37  */
38 unsigned char pci_bus_max_busnr(struct pci_bus* bus)
39 {
40 	struct list_head *tmp;
41 	unsigned char max, n;
42 
43 	max = bus->subordinate;
44 	list_for_each(tmp, &bus->children) {
45 		n = pci_bus_max_busnr(pci_bus_b(tmp));
46 		if(n > max)
47 			max = n;
48 	}
49 	return max;
50 }
51 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
52 
53 #if 0
54 /**
55  * pci_max_busnr - returns maximum PCI bus number
56  *
57  * Returns the highest PCI bus number present in the system global list of
58  * PCI buses.
59  */
60 unsigned char __devinit
61 pci_max_busnr(void)
62 {
63 	struct pci_bus *bus = NULL;
64 	unsigned char max, n;
65 
66 	max = 0;
67 	while ((bus = pci_find_next_bus(bus)) != NULL) {
68 		n = pci_bus_max_busnr(bus);
69 		if(n > max)
70 			max = n;
71 	}
72 	return max;
73 }
74 
75 #endif  /*  0  */
76 
77 #define PCI_FIND_CAP_TTL	48
78 
79 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
80 				   u8 pos, int cap, int *ttl)
81 {
82 	u8 id;
83 
84 	while ((*ttl)--) {
85 		pci_bus_read_config_byte(bus, devfn, pos, &pos);
86 		if (pos < 0x40)
87 			break;
88 		pos &= ~3;
89 		pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
90 					 &id);
91 		if (id == 0xff)
92 			break;
93 		if (id == cap)
94 			return pos;
95 		pos += PCI_CAP_LIST_NEXT;
96 	}
97 	return 0;
98 }
99 
100 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
101 			       u8 pos, int cap)
102 {
103 	int ttl = PCI_FIND_CAP_TTL;
104 
105 	return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
106 }
107 
108 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
109 {
110 	return __pci_find_next_cap(dev->bus, dev->devfn,
111 				   pos + PCI_CAP_LIST_NEXT, cap);
112 }
113 EXPORT_SYMBOL_GPL(pci_find_next_capability);
114 
115 static int __pci_bus_find_cap_start(struct pci_bus *bus,
116 				    unsigned int devfn, u8 hdr_type)
117 {
118 	u16 status;
119 
120 	pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
121 	if (!(status & PCI_STATUS_CAP_LIST))
122 		return 0;
123 
124 	switch (hdr_type) {
125 	case PCI_HEADER_TYPE_NORMAL:
126 	case PCI_HEADER_TYPE_BRIDGE:
127 		return PCI_CAPABILITY_LIST;
128 	case PCI_HEADER_TYPE_CARDBUS:
129 		return PCI_CB_CAPABILITY_LIST;
130 	default:
131 		return 0;
132 	}
133 
134 	return 0;
135 }
136 
137 /**
138  * pci_find_capability - query for devices' capabilities
139  * @dev: PCI device to query
140  * @cap: capability code
141  *
142  * Tell if a device supports a given PCI capability.
143  * Returns the address of the requested capability structure within the
144  * device's PCI configuration space or 0 in case the device does not
145  * support it.  Possible values for @cap:
146  *
147  *  %PCI_CAP_ID_PM           Power Management
148  *  %PCI_CAP_ID_AGP          Accelerated Graphics Port
149  *  %PCI_CAP_ID_VPD          Vital Product Data
150  *  %PCI_CAP_ID_SLOTID       Slot Identification
151  *  %PCI_CAP_ID_MSI          Message Signalled Interrupts
152  *  %PCI_CAP_ID_CHSWP        CompactPCI HotSwap
153  *  %PCI_CAP_ID_PCIX         PCI-X
154  *  %PCI_CAP_ID_EXP          PCI Express
155  */
156 int pci_find_capability(struct pci_dev *dev, int cap)
157 {
158 	int pos;
159 
160 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
161 	if (pos)
162 		pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
163 
164 	return pos;
165 }
166 
167 /**
168  * pci_bus_find_capability - query for devices' capabilities
169  * @bus:   the PCI bus to query
170  * @devfn: PCI device to query
171  * @cap:   capability code
172  *
173  * Like pci_find_capability() but works for pci devices that do not have a
174  * pci_dev structure set up yet.
175  *
176  * Returns the address of the requested capability structure within the
177  * device's PCI configuration space or 0 in case the device does not
178  * support it.
179  */
180 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
181 {
182 	int pos;
183 	u8 hdr_type;
184 
185 	pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
186 
187 	pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
188 	if (pos)
189 		pos = __pci_find_next_cap(bus, devfn, pos, cap);
190 
191 	return pos;
192 }
193 
194 /**
195  * pci_find_ext_capability - Find an extended capability
196  * @dev: PCI device to query
197  * @cap: capability code
198  *
199  * Returns the address of the requested extended capability structure
200  * within the device's PCI configuration space or 0 if the device does
201  * not support it.  Possible values for @cap:
202  *
203  *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
204  *  %PCI_EXT_CAP_ID_VC		Virtual Channel
205  *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
206  *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
207  */
208 int pci_find_ext_capability(struct pci_dev *dev, int cap)
209 {
210 	u32 header;
211 	int ttl = 480; /* 3840 bytes, minimum 8 bytes per capability */
212 	int pos = 0x100;
213 
214 	if (dev->cfg_size <= 256)
215 		return 0;
216 
217 	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
218 		return 0;
219 
220 	/*
221 	 * If we have no capabilities, this is indicated by cap ID,
222 	 * cap version and next pointer all being 0.
223 	 */
224 	if (header == 0)
225 		return 0;
226 
227 	while (ttl-- > 0) {
228 		if (PCI_EXT_CAP_ID(header) == cap)
229 			return pos;
230 
231 		pos = PCI_EXT_CAP_NEXT(header);
232 		if (pos < 0x100)
233 			break;
234 
235 		if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
236 			break;
237 	}
238 
239 	return 0;
240 }
241 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
242 
243 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
244 {
245 	int rc, ttl = PCI_FIND_CAP_TTL;
246 	u8 cap, mask;
247 
248 	if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
249 		mask = HT_3BIT_CAP_MASK;
250 	else
251 		mask = HT_5BIT_CAP_MASK;
252 
253 	pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
254 				      PCI_CAP_ID_HT, &ttl);
255 	while (pos) {
256 		rc = pci_read_config_byte(dev, pos + 3, &cap);
257 		if (rc != PCIBIOS_SUCCESSFUL)
258 			return 0;
259 
260 		if ((cap & mask) == ht_cap)
261 			return pos;
262 
263 		pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
264 					      pos + PCI_CAP_LIST_NEXT,
265 					      PCI_CAP_ID_HT, &ttl);
266 	}
267 
268 	return 0;
269 }
270 /**
271  * pci_find_next_ht_capability - query a device's Hypertransport capabilities
272  * @dev: PCI device to query
273  * @pos: Position from which to continue searching
274  * @ht_cap: Hypertransport capability code
275  *
276  * To be used in conjunction with pci_find_ht_capability() to search for
277  * all capabilities matching @ht_cap. @pos should always be a value returned
278  * from pci_find_ht_capability().
279  *
280  * NB. To be 100% safe against broken PCI devices, the caller should take
281  * steps to avoid an infinite loop.
282  */
283 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
284 {
285 	return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
286 }
287 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
288 
289 /**
290  * pci_find_ht_capability - query a device's Hypertransport capabilities
291  * @dev: PCI device to query
292  * @ht_cap: Hypertransport capability code
293  *
294  * Tell if a device supports a given Hypertransport capability.
295  * Returns an address within the device's PCI configuration space
296  * or 0 in case the device does not support the request capability.
297  * The address points to the PCI capability, of type PCI_CAP_ID_HT,
298  * which has a Hypertransport capability matching @ht_cap.
299  */
300 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
301 {
302 	int pos;
303 
304 	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
305 	if (pos)
306 		pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
307 
308 	return pos;
309 }
310 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
311 
312 /**
313  * pci_find_parent_resource - return resource region of parent bus of given region
314  * @dev: PCI device structure contains resources to be searched
315  * @res: child resource record for which parent is sought
316  *
317  *  For given resource region of given device, return the resource
318  *  region of parent bus the given region is contained in or where
319  *  it should be allocated from.
320  */
321 struct resource *
322 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
323 {
324 	const struct pci_bus *bus = dev->bus;
325 	int i;
326 	struct resource *best = NULL;
327 
328 	for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
329 		struct resource *r = bus->resource[i];
330 		if (!r)
331 			continue;
332 		if (res->start && !(res->start >= r->start && res->end <= r->end))
333 			continue;	/* Not contained */
334 		if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
335 			continue;	/* Wrong type */
336 		if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
337 			return r;	/* Exact match */
338 		if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
339 			best = r;	/* Approximating prefetchable by non-prefetchable */
340 	}
341 	return best;
342 }
343 
344 /**
345  * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
346  * @dev: PCI device to have its BARs restored
347  *
348  * Restore the BAR values for a given device, so as to make it
349  * accessible by its driver.
350  */
351 void
352 pci_restore_bars(struct pci_dev *dev)
353 {
354 	int i, numres;
355 
356 	switch (dev->hdr_type) {
357 	case PCI_HEADER_TYPE_NORMAL:
358 		numres = 6;
359 		break;
360 	case PCI_HEADER_TYPE_BRIDGE:
361 		numres = 2;
362 		break;
363 	case PCI_HEADER_TYPE_CARDBUS:
364 		numres = 1;
365 		break;
366 	default:
367 		/* Should never get here, but just in case... */
368 		return;
369 	}
370 
371 	for (i = 0; i < numres; i ++)
372 		pci_update_resource(dev, &dev->resource[i], i);
373 }
374 
375 int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t t);
376 
377 /**
378  * pci_set_power_state - Set the power state of a PCI device
379  * @dev: PCI device to be suspended
380  * @state: PCI power state (D0, D1, D2, D3hot, D3cold) we're entering
381  *
382  * Transition a device to a new power state, using the Power Management
383  * Capabilities in the device's config space.
384  *
385  * RETURN VALUE:
386  * -EINVAL if trying to enter a lower state than we're already in.
387  * 0 if we're already in the requested state.
388  * -EIO if device does not support PCI PM.
389  * 0 if we can successfully change the power state.
390  */
391 int
392 pci_set_power_state(struct pci_dev *dev, pci_power_t state)
393 {
394 	int pm, need_restore = 0;
395 	u16 pmcsr, pmc;
396 
397 	/* bound the state we're entering */
398 	if (state > PCI_D3hot)
399 		state = PCI_D3hot;
400 
401 	/*
402 	 * If the device or the parent bridge can't support PCI PM, ignore
403 	 * the request if we're doing anything besides putting it into D0
404 	 * (which would only happen on boot).
405 	 */
406 	if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
407 		return 0;
408 
409 	/* find PCI PM capability in list */
410 	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
411 
412 	/* abort if the device doesn't support PM capabilities */
413 	if (!pm)
414 		return -EIO;
415 
416 	/* Validate current state:
417 	 * Can enter D0 from any state, but if we can only go deeper
418 	 * to sleep if we're already in a low power state
419 	 */
420 	if (state != PCI_D0 && dev->current_state > state) {
421 		printk(KERN_ERR "%s(): %s: state=%d, current state=%d\n",
422 			__FUNCTION__, pci_name(dev), state, dev->current_state);
423 		return -EINVAL;
424 	} else if (dev->current_state == state)
425 		return 0;        /* we're already there */
426 
427 
428 	pci_read_config_word(dev,pm + PCI_PM_PMC,&pmc);
429 	if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
430 		printk(KERN_DEBUG
431 		       "PCI: %s has unsupported PM cap regs version (%u)\n",
432 		       pci_name(dev), pmc & PCI_PM_CAP_VER_MASK);
433 		return -EIO;
434 	}
435 
436 	/* check if this device supports the desired state */
437 	if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
438 		return -EIO;
439 	else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2))
440 		return -EIO;
441 
442 	pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
443 
444 	/* If we're (effectively) in D3, force entire word to 0.
445 	 * This doesn't affect PME_Status, disables PME_En, and
446 	 * sets PowerState to 0.
447 	 */
448 	switch (dev->current_state) {
449 	case PCI_D0:
450 	case PCI_D1:
451 	case PCI_D2:
452 		pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
453 		pmcsr |= state;
454 		break;
455 	case PCI_UNKNOWN: /* Boot-up */
456 		if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
457 		 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
458 			need_restore = 1;
459 		/* Fall-through: force to D0 */
460 	default:
461 		pmcsr = 0;
462 		break;
463 	}
464 
465 	/* enter specified state */
466 	pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
467 
468 	/* Mandatory power management transition delays */
469 	/* see PCI PM 1.1 5.6.1 table 18 */
470 	if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
471 		msleep(pci_pm_d3_delay);
472 	else if (state == PCI_D2 || dev->current_state == PCI_D2)
473 		udelay(200);
474 
475 	/*
476 	 * Give firmware a chance to be called, such as ACPI _PRx, _PSx
477 	 * Firmware method after native method ?
478 	 */
479 	if (platform_pci_set_power_state)
480 		platform_pci_set_power_state(dev, state);
481 
482 	dev->current_state = state;
483 
484 	/* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
485 	 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
486 	 * from D3hot to D0 _may_ perform an internal reset, thereby
487 	 * going to "D0 Uninitialized" rather than "D0 Initialized".
488 	 * For example, at least some versions of the 3c905B and the
489 	 * 3c556B exhibit this behaviour.
490 	 *
491 	 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
492 	 * devices in a D3hot state at boot.  Consequently, we need to
493 	 * restore at least the BARs so that the device will be
494 	 * accessible to its driver.
495 	 */
496 	if (need_restore)
497 		pci_restore_bars(dev);
498 
499 	return 0;
500 }
501 
502 pci_power_t (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
503 
504 /**
505  * pci_choose_state - Choose the power state of a PCI device
506  * @dev: PCI device to be suspended
507  * @state: target sleep state for the whole system. This is the value
508  *	that is passed to suspend() function.
509  *
510  * Returns PCI power state suitable for given device and given system
511  * message.
512  */
513 
514 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
515 {
516 	pci_power_t ret;
517 
518 	if (!pci_find_capability(dev, PCI_CAP_ID_PM))
519 		return PCI_D0;
520 
521 	if (platform_pci_choose_state) {
522 		ret = platform_pci_choose_state(dev, state);
523 		if (ret != PCI_POWER_ERROR)
524 			return ret;
525 	}
526 
527 	switch (state.event) {
528 	case PM_EVENT_ON:
529 		return PCI_D0;
530 	case PM_EVENT_FREEZE:
531 	case PM_EVENT_PRETHAW:
532 		/* REVISIT both freeze and pre-thaw "should" use D0 */
533 	case PM_EVENT_SUSPEND:
534 		return PCI_D3hot;
535 	default:
536 		printk("Unrecognized suspend event %d\n", state.event);
537 		BUG();
538 	}
539 	return PCI_D0;
540 }
541 
542 EXPORT_SYMBOL(pci_choose_state);
543 
544 static int pci_save_pcie_state(struct pci_dev *dev)
545 {
546 	int pos, i = 0;
547 	struct pci_cap_saved_state *save_state;
548 	u16 *cap;
549 
550 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
551 	if (pos <= 0)
552 		return 0;
553 
554 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
555 	if (!save_state)
556 		save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);
557 	if (!save_state) {
558 		dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
559 		return -ENOMEM;
560 	}
561 	cap = (u16 *)&save_state->data[0];
562 
563 	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
564 	pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
565 	pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
566 	pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
567 	pci_add_saved_cap(dev, save_state);
568 	return 0;
569 }
570 
571 static void pci_restore_pcie_state(struct pci_dev *dev)
572 {
573 	int i = 0, pos;
574 	struct pci_cap_saved_state *save_state;
575 	u16 *cap;
576 
577 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
578 	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
579 	if (!save_state || pos <= 0)
580 		return;
581 	cap = (u16 *)&save_state->data[0];
582 
583 	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
584 	pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
585 	pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
586 	pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
587 }
588 
589 
590 static int pci_save_pcix_state(struct pci_dev *dev)
591 {
592 	int pos, i = 0;
593 	struct pci_cap_saved_state *save_state;
594 	u16 *cap;
595 
596 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
597 	if (pos <= 0)
598 		return 0;
599 
600 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
601 	if (!save_state)
602 		save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);
603 	if (!save_state) {
604 		dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
605 		return -ENOMEM;
606 	}
607 	cap = (u16 *)&save_state->data[0];
608 
609 	pci_read_config_word(dev, pos + PCI_X_CMD, &cap[i++]);
610 	pci_add_saved_cap(dev, save_state);
611 	return 0;
612 }
613 
614 static void pci_restore_pcix_state(struct pci_dev *dev)
615 {
616 	int i = 0, pos;
617 	struct pci_cap_saved_state *save_state;
618 	u16 *cap;
619 
620 	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
621 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
622 	if (!save_state || pos <= 0)
623 		return;
624 	cap = (u16 *)&save_state->data[0];
625 
626 	pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
627 }
628 
629 
630 /**
631  * pci_save_state - save the PCI configuration space of a device before suspending
632  * @dev: - PCI device that we're dealing with
633  */
634 int
635 pci_save_state(struct pci_dev *dev)
636 {
637 	int i;
638 	/* XXX: 100% dword access ok here? */
639 	for (i = 0; i < 16; i++)
640 		pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
641 	if ((i = pci_save_pcie_state(dev)) != 0)
642 		return i;
643 	if ((i = pci_save_pcix_state(dev)) != 0)
644 		return i;
645 	return 0;
646 }
647 
648 /**
649  * pci_restore_state - Restore the saved state of a PCI device
650  * @dev: - PCI device that we're dealing with
651  */
652 int
653 pci_restore_state(struct pci_dev *dev)
654 {
655 	int i;
656 	int val;
657 
658 	/* PCI Express register must be restored first */
659 	pci_restore_pcie_state(dev);
660 
661 	/*
662 	 * The Base Address register should be programmed before the command
663 	 * register(s)
664 	 */
665 	for (i = 15; i >= 0; i--) {
666 		pci_read_config_dword(dev, i * 4, &val);
667 		if (val != dev->saved_config_space[i]) {
668 			printk(KERN_DEBUG "PM: Writing back config space on "
669 				"device %s at offset %x (was %x, writing %x)\n",
670 				pci_name(dev), i,
671 				val, (int)dev->saved_config_space[i]);
672 			pci_write_config_dword(dev,i * 4,
673 				dev->saved_config_space[i]);
674 		}
675 	}
676 	pci_restore_pcix_state(dev);
677 	pci_restore_msi_state(dev);
678 
679 	return 0;
680 }
681 
682 static int do_pci_enable_device(struct pci_dev *dev, int bars)
683 {
684 	int err;
685 
686 	err = pci_set_power_state(dev, PCI_D0);
687 	if (err < 0 && err != -EIO)
688 		return err;
689 	err = pcibios_enable_device(dev, bars);
690 	if (err < 0)
691 		return err;
692 	pci_fixup_device(pci_fixup_enable, dev);
693 
694 	return 0;
695 }
696 
697 /**
698  * __pci_reenable_device - Resume abandoned device
699  * @dev: PCI device to be resumed
700  *
701  *  Note this function is a backend of pci_default_resume and is not supposed
702  *  to be called by normal code, write proper resume handler and use it instead.
703  */
704 int
705 __pci_reenable_device(struct pci_dev *dev)
706 {
707 	if (atomic_read(&dev->enable_cnt))
708 		return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
709 	return 0;
710 }
711 
712 /**
713  * pci_enable_device_bars - Initialize some of a device for use
714  * @dev: PCI device to be initialized
715  * @bars: bitmask of BAR's that must be configured
716  *
717  *  Initialize device before it's used by a driver. Ask low-level code
718  *  to enable selected I/O and memory resources. Wake up the device if it
719  *  was suspended. Beware, this function can fail.
720  */
721 int
722 pci_enable_device_bars(struct pci_dev *dev, int bars)
723 {
724 	int err;
725 
726 	if (atomic_add_return(1, &dev->enable_cnt) > 1)
727 		return 0;		/* already enabled */
728 
729 	err = do_pci_enable_device(dev, bars);
730 	if (err < 0)
731 		atomic_dec(&dev->enable_cnt);
732 	return err;
733 }
734 
735 /**
736  * pci_enable_device - Initialize device before it's used by a driver.
737  * @dev: PCI device to be initialized
738  *
739  *  Initialize device before it's used by a driver. Ask low-level code
740  *  to enable I/O and memory. Wake up the device if it was suspended.
741  *  Beware, this function can fail.
742  *
743  *  Note we don't actually enable the device many times if we call
744  *  this function repeatedly (we just increment the count).
745  */
746 int pci_enable_device(struct pci_dev *dev)
747 {
748 	return pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
749 }
750 
751 /*
752  * Managed PCI resources.  This manages device on/off, intx/msi/msix
753  * on/off and BAR regions.  pci_dev itself records msi/msix status, so
754  * there's no need to track it separately.  pci_devres is initialized
755  * when a device is enabled using managed PCI device enable interface.
756  */
757 struct pci_devres {
758 	unsigned int enabled:1;
759 	unsigned int pinned:1;
760 	unsigned int orig_intx:1;
761 	unsigned int restore_intx:1;
762 	u32 region_mask;
763 };
764 
765 static void pcim_release(struct device *gendev, void *res)
766 {
767 	struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
768 	struct pci_devres *this = res;
769 	int i;
770 
771 	if (dev->msi_enabled)
772 		pci_disable_msi(dev);
773 	if (dev->msix_enabled)
774 		pci_disable_msix(dev);
775 
776 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
777 		if (this->region_mask & (1 << i))
778 			pci_release_region(dev, i);
779 
780 	if (this->restore_intx)
781 		pci_intx(dev, this->orig_intx);
782 
783 	if (this->enabled && !this->pinned)
784 		pci_disable_device(dev);
785 }
786 
787 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
788 {
789 	struct pci_devres *dr, *new_dr;
790 
791 	dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
792 	if (dr)
793 		return dr;
794 
795 	new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
796 	if (!new_dr)
797 		return NULL;
798 	return devres_get(&pdev->dev, new_dr, NULL, NULL);
799 }
800 
801 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
802 {
803 	if (pci_is_managed(pdev))
804 		return devres_find(&pdev->dev, pcim_release, NULL, NULL);
805 	return NULL;
806 }
807 
808 /**
809  * pcim_enable_device - Managed pci_enable_device()
810  * @pdev: PCI device to be initialized
811  *
812  * Managed pci_enable_device().
813  */
814 int pcim_enable_device(struct pci_dev *pdev)
815 {
816 	struct pci_devres *dr;
817 	int rc;
818 
819 	dr = get_pci_dr(pdev);
820 	if (unlikely(!dr))
821 		return -ENOMEM;
822 	WARN_ON(!!dr->enabled);
823 
824 	rc = pci_enable_device(pdev);
825 	if (!rc) {
826 		pdev->is_managed = 1;
827 		dr->enabled = 1;
828 	}
829 	return rc;
830 }
831 
832 /**
833  * pcim_pin_device - Pin managed PCI device
834  * @pdev: PCI device to pin
835  *
836  * Pin managed PCI device @pdev.  Pinned device won't be disabled on
837  * driver detach.  @pdev must have been enabled with
838  * pcim_enable_device().
839  */
840 void pcim_pin_device(struct pci_dev *pdev)
841 {
842 	struct pci_devres *dr;
843 
844 	dr = find_pci_dr(pdev);
845 	WARN_ON(!dr || !dr->enabled);
846 	if (dr)
847 		dr->pinned = 1;
848 }
849 
850 /**
851  * pcibios_disable_device - disable arch specific PCI resources for device dev
852  * @dev: the PCI device to disable
853  *
854  * Disables architecture specific PCI resources for the device. This
855  * is the default implementation. Architecture implementations can
856  * override this.
857  */
858 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
859 
860 /**
861  * pci_disable_device - Disable PCI device after use
862  * @dev: PCI device to be disabled
863  *
864  * Signal to the system that the PCI device is not in use by the system
865  * anymore.  This only involves disabling PCI bus-mastering, if active.
866  *
867  * Note we don't actually disable the device until all callers of
868  * pci_device_enable() have called pci_device_disable().
869  */
870 void
871 pci_disable_device(struct pci_dev *dev)
872 {
873 	struct pci_devres *dr;
874 	u16 pci_command;
875 
876 	dr = find_pci_dr(dev);
877 	if (dr)
878 		dr->enabled = 0;
879 
880 	if (atomic_sub_return(1, &dev->enable_cnt) != 0)
881 		return;
882 
883 	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
884 	if (pci_command & PCI_COMMAND_MASTER) {
885 		pci_command &= ~PCI_COMMAND_MASTER;
886 		pci_write_config_word(dev, PCI_COMMAND, pci_command);
887 	}
888 	dev->is_busmaster = 0;
889 
890 	pcibios_disable_device(dev);
891 }
892 
893 /**
894  * pcibios_set_pcie_reset_state - set reset state for device dev
895  * @dev: the PCI-E device reset
896  * @state: Reset state to enter into
897  *
898  *
899  * Sets the PCI-E reset state for the device. This is the default
900  * implementation. Architecture implementations can override this.
901  */
902 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
903 							enum pcie_reset_state state)
904 {
905 	return -EINVAL;
906 }
907 
908 /**
909  * pci_set_pcie_reset_state - set reset state for device dev
910  * @dev: the PCI-E device reset
911  * @state: Reset state to enter into
912  *
913  *
914  * Sets the PCI reset state for the device.
915  */
916 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
917 {
918 	return pcibios_set_pcie_reset_state(dev, state);
919 }
920 
921 /**
922  * pci_enable_wake - enable PCI device as wakeup event source
923  * @dev: PCI device affected
924  * @state: PCI state from which device will issue wakeup events
925  * @enable: True to enable event generation; false to disable
926  *
927  * This enables the device as a wakeup event source, or disables it.
928  * When such events involves platform-specific hooks, those hooks are
929  * called automatically by this routine.
930  *
931  * Devices with legacy power management (no standard PCI PM capabilities)
932  * always require such platform hooks.  Depending on the platform, devices
933  * supporting the standard PCI PME# signal may require such platform hooks;
934  * they always update bits in config space to allow PME# generation.
935  *
936  * -EIO is returned if the device can't ever be a wakeup event source.
937  * -EINVAL is returned if the device can't generate wakeup events from
938  * the specified PCI state.  Returns zero if the operation is successful.
939  */
940 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
941 {
942 	int pm;
943 	int status;
944 	u16 value;
945 
946 	/* Note that drivers should verify device_may_wakeup(&dev->dev)
947 	 * before calling this function.  Platform code should report
948 	 * errors when drivers try to enable wakeup on devices that
949 	 * can't issue wakeups, or on which wakeups were disabled by
950 	 * userspace updating the /sys/devices.../power/wakeup file.
951 	 */
952 
953 	status = call_platform_enable_wakeup(&dev->dev, enable);
954 
955 	/* find PCI PM capability in list */
956 	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
957 
958 	/* If device doesn't support PM Capabilities, but caller wants to
959 	 * disable wake events, it's a NOP.  Otherwise fail unless the
960 	 * platform hooks handled this legacy device already.
961 	 */
962 	if (!pm)
963 		return enable ? status : 0;
964 
965 	/* Check device's ability to generate PME# */
966 	pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
967 
968 	value &= PCI_PM_CAP_PME_MASK;
969 	value >>= ffs(PCI_PM_CAP_PME_MASK) - 1;   /* First bit of mask */
970 
971 	/* Check if it can generate PME# from requested state. */
972 	if (!value || !(value & (1 << state))) {
973 		/* if it can't, revert what the platform hook changed,
974 		 * always reporting the base "EINVAL, can't PME#" error
975 		 */
976 		if (enable)
977 			call_platform_enable_wakeup(&dev->dev, 0);
978 		return enable ? -EINVAL : 0;
979 	}
980 
981 	pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
982 
983 	/* Clear PME_Status by writing 1 to it and enable PME# */
984 	value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
985 
986 	if (!enable)
987 		value &= ~PCI_PM_CTRL_PME_ENABLE;
988 
989 	pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
990 
991 	return 0;
992 }
993 
994 int
995 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
996 {
997 	u8 pin;
998 
999 	pin = dev->pin;
1000 	if (!pin)
1001 		return -1;
1002 	pin--;
1003 	while (dev->bus->self) {
1004 		pin = (pin + PCI_SLOT(dev->devfn)) % 4;
1005 		dev = dev->bus->self;
1006 	}
1007 	*bridge = dev;
1008 	return pin;
1009 }
1010 
1011 /**
1012  *	pci_release_region - Release a PCI bar
1013  *	@pdev: PCI device whose resources were previously reserved by pci_request_region
1014  *	@bar: BAR to release
1015  *
1016  *	Releases the PCI I/O and memory resources previously reserved by a
1017  *	successful call to pci_request_region.  Call this function only
1018  *	after all use of the PCI regions has ceased.
1019  */
1020 void pci_release_region(struct pci_dev *pdev, int bar)
1021 {
1022 	struct pci_devres *dr;
1023 
1024 	if (pci_resource_len(pdev, bar) == 0)
1025 		return;
1026 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1027 		release_region(pci_resource_start(pdev, bar),
1028 				pci_resource_len(pdev, bar));
1029 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1030 		release_mem_region(pci_resource_start(pdev, bar),
1031 				pci_resource_len(pdev, bar));
1032 
1033 	dr = find_pci_dr(pdev);
1034 	if (dr)
1035 		dr->region_mask &= ~(1 << bar);
1036 }
1037 
1038 /**
1039  *	pci_request_region - Reserved PCI I/O and memory resource
1040  *	@pdev: PCI device whose resources are to be reserved
1041  *	@bar: BAR to be reserved
1042  *	@res_name: Name to be associated with resource.
1043  *
1044  *	Mark the PCI region associated with PCI device @pdev BR @bar as
1045  *	being reserved by owner @res_name.  Do not access any
1046  *	address inside the PCI regions unless this call returns
1047  *	successfully.
1048  *
1049  *	Returns 0 on success, or %EBUSY on error.  A warning
1050  *	message is also printed on failure.
1051  */
1052 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1053 {
1054 	struct pci_devres *dr;
1055 
1056 	if (pci_resource_len(pdev, bar) == 0)
1057 		return 0;
1058 
1059 	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1060 		if (!request_region(pci_resource_start(pdev, bar),
1061 			    pci_resource_len(pdev, bar), res_name))
1062 			goto err_out;
1063 	}
1064 	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1065 		if (!request_mem_region(pci_resource_start(pdev, bar),
1066 				        pci_resource_len(pdev, bar), res_name))
1067 			goto err_out;
1068 	}
1069 
1070 	dr = find_pci_dr(pdev);
1071 	if (dr)
1072 		dr->region_mask |= 1 << bar;
1073 
1074 	return 0;
1075 
1076 err_out:
1077 	printk (KERN_WARNING "PCI: Unable to reserve %s region #%d:%llx@%llx "
1078 		"for device %s\n",
1079 		pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
1080 		bar + 1, /* PCI BAR # */
1081 		(unsigned long long)pci_resource_len(pdev, bar),
1082 		(unsigned long long)pci_resource_start(pdev, bar),
1083 		pci_name(pdev));
1084 	return -EBUSY;
1085 }
1086 
1087 /**
1088  * pci_release_selected_regions - Release selected PCI I/O and memory resources
1089  * @pdev: PCI device whose resources were previously reserved
1090  * @bars: Bitmask of BARs to be released
1091  *
1092  * Release selected PCI I/O and memory resources previously reserved.
1093  * Call this function only after all use of the PCI regions has ceased.
1094  */
1095 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1096 {
1097 	int i;
1098 
1099 	for (i = 0; i < 6; i++)
1100 		if (bars & (1 << i))
1101 			pci_release_region(pdev, i);
1102 }
1103 
1104 /**
1105  * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
1106  * @pdev: PCI device whose resources are to be reserved
1107  * @bars: Bitmask of BARs to be requested
1108  * @res_name: Name to be associated with resource
1109  */
1110 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
1111 				 const char *res_name)
1112 {
1113 	int i;
1114 
1115 	for (i = 0; i < 6; i++)
1116 		if (bars & (1 << i))
1117 			if(pci_request_region(pdev, i, res_name))
1118 				goto err_out;
1119 	return 0;
1120 
1121 err_out:
1122 	while(--i >= 0)
1123 		if (bars & (1 << i))
1124 			pci_release_region(pdev, i);
1125 
1126 	return -EBUSY;
1127 }
1128 
1129 /**
1130  *	pci_release_regions - Release reserved PCI I/O and memory resources
1131  *	@pdev: PCI device whose resources were previously reserved by pci_request_regions
1132  *
1133  *	Releases all PCI I/O and memory resources previously reserved by a
1134  *	successful call to pci_request_regions.  Call this function only
1135  *	after all use of the PCI regions has ceased.
1136  */
1137 
1138 void pci_release_regions(struct pci_dev *pdev)
1139 {
1140 	pci_release_selected_regions(pdev, (1 << 6) - 1);
1141 }
1142 
1143 /**
1144  *	pci_request_regions - Reserved PCI I/O and memory resources
1145  *	@pdev: PCI device whose resources are to be reserved
1146  *	@res_name: Name to be associated with resource.
1147  *
1148  *	Mark all PCI regions associated with PCI device @pdev as
1149  *	being reserved by owner @res_name.  Do not access any
1150  *	address inside the PCI regions unless this call returns
1151  *	successfully.
1152  *
1153  *	Returns 0 on success, or %EBUSY on error.  A warning
1154  *	message is also printed on failure.
1155  */
1156 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
1157 {
1158 	return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
1159 }
1160 
1161 /**
1162  * pci_set_master - enables bus-mastering for device dev
1163  * @dev: the PCI device to enable
1164  *
1165  * Enables bus-mastering on the device and calls pcibios_set_master()
1166  * to do the needed arch specific settings.
1167  */
1168 void
1169 pci_set_master(struct pci_dev *dev)
1170 {
1171 	u16 cmd;
1172 
1173 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1174 	if (! (cmd & PCI_COMMAND_MASTER)) {
1175 		pr_debug("PCI: Enabling bus mastering for device %s\n", pci_name(dev));
1176 		cmd |= PCI_COMMAND_MASTER;
1177 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1178 	}
1179 	dev->is_busmaster = 1;
1180 	pcibios_set_master(dev);
1181 }
1182 
1183 #ifdef PCI_DISABLE_MWI
1184 int pci_set_mwi(struct pci_dev *dev)
1185 {
1186 	return 0;
1187 }
1188 
1189 int pci_try_set_mwi(struct pci_dev *dev)
1190 {
1191 	return 0;
1192 }
1193 
1194 void pci_clear_mwi(struct pci_dev *dev)
1195 {
1196 }
1197 
1198 #else
1199 
1200 #ifndef PCI_CACHE_LINE_BYTES
1201 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
1202 #endif
1203 
1204 /* This can be overridden by arch code. */
1205 /* Don't forget this is measured in 32-bit words, not bytes */
1206 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
1207 
1208 /**
1209  * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1210  * @dev: the PCI device for which MWI is to be enabled
1211  *
1212  * Helper function for pci_set_mwi.
1213  * Originally copied from drivers/net/acenic.c.
1214  * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1215  *
1216  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1217  */
1218 static int
1219 pci_set_cacheline_size(struct pci_dev *dev)
1220 {
1221 	u8 cacheline_size;
1222 
1223 	if (!pci_cache_line_size)
1224 		return -EINVAL;		/* The system doesn't support MWI. */
1225 
1226 	/* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1227 	   equal to or multiple of the right value. */
1228 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1229 	if (cacheline_size >= pci_cache_line_size &&
1230 	    (cacheline_size % pci_cache_line_size) == 0)
1231 		return 0;
1232 
1233 	/* Write the correct value. */
1234 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1235 	/* Read it back. */
1236 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1237 	if (cacheline_size == pci_cache_line_size)
1238 		return 0;
1239 
1240 	printk(KERN_DEBUG "PCI: cache line size of %d is not supported "
1241 	       "by device %s\n", pci_cache_line_size << 2, pci_name(dev));
1242 
1243 	return -EINVAL;
1244 }
1245 
1246 /**
1247  * pci_set_mwi - enables memory-write-invalidate PCI transaction
1248  * @dev: the PCI device for which MWI is enabled
1249  *
1250  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1251  *
1252  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1253  */
1254 int
1255 pci_set_mwi(struct pci_dev *dev)
1256 {
1257 	int rc;
1258 	u16 cmd;
1259 
1260 	rc = pci_set_cacheline_size(dev);
1261 	if (rc)
1262 		return rc;
1263 
1264 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1265 	if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1266 		pr_debug("PCI: Enabling Mem-Wr-Inval for device %s\n",
1267 			pci_name(dev));
1268 		cmd |= PCI_COMMAND_INVALIDATE;
1269 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1270 	}
1271 
1272 	return 0;
1273 }
1274 
1275 /**
1276  * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
1277  * @dev: the PCI device for which MWI is enabled
1278  *
1279  * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1280  * Callers are not required to check the return value.
1281  *
1282  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1283  */
1284 int pci_try_set_mwi(struct pci_dev *dev)
1285 {
1286 	int rc = pci_set_mwi(dev);
1287 	return rc;
1288 }
1289 
1290 /**
1291  * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1292  * @dev: the PCI device to disable
1293  *
1294  * Disables PCI Memory-Write-Invalidate transaction on the device
1295  */
1296 void
1297 pci_clear_mwi(struct pci_dev *dev)
1298 {
1299 	u16 cmd;
1300 
1301 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
1302 	if (cmd & PCI_COMMAND_INVALIDATE) {
1303 		cmd &= ~PCI_COMMAND_INVALIDATE;
1304 		pci_write_config_word(dev, PCI_COMMAND, cmd);
1305 	}
1306 }
1307 #endif /* ! PCI_DISABLE_MWI */
1308 
1309 /**
1310  * pci_intx - enables/disables PCI INTx for device dev
1311  * @pdev: the PCI device to operate on
1312  * @enable: boolean: whether to enable or disable PCI INTx
1313  *
1314  * Enables/disables PCI INTx for device dev
1315  */
1316 void
1317 pci_intx(struct pci_dev *pdev, int enable)
1318 {
1319 	u16 pci_command, new;
1320 
1321 	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1322 
1323 	if (enable) {
1324 		new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1325 	} else {
1326 		new = pci_command | PCI_COMMAND_INTX_DISABLE;
1327 	}
1328 
1329 	if (new != pci_command) {
1330 		struct pci_devres *dr;
1331 
1332 		pci_write_config_word(pdev, PCI_COMMAND, new);
1333 
1334 		dr = find_pci_dr(pdev);
1335 		if (dr && !dr->restore_intx) {
1336 			dr->restore_intx = 1;
1337 			dr->orig_intx = !enable;
1338 		}
1339 	}
1340 }
1341 
1342 /**
1343  * pci_msi_off - disables any msi or msix capabilities
1344  * @dev: the PCI device to operate on
1345  *
1346  * If you want to use msi see pci_enable_msi and friends.
1347  * This is a lower level primitive that allows us to disable
1348  * msi operation at the device level.
1349  */
1350 void pci_msi_off(struct pci_dev *dev)
1351 {
1352 	int pos;
1353 	u16 control;
1354 
1355 	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
1356 	if (pos) {
1357 		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
1358 		control &= ~PCI_MSI_FLAGS_ENABLE;
1359 		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
1360 	}
1361 	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1362 	if (pos) {
1363 		pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
1364 		control &= ~PCI_MSIX_FLAGS_ENABLE;
1365 		pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
1366 	}
1367 }
1368 
1369 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
1370 /*
1371  * These can be overridden by arch-specific implementations
1372  */
1373 int
1374 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
1375 {
1376 	if (!pci_dma_supported(dev, mask))
1377 		return -EIO;
1378 
1379 	dev->dma_mask = mask;
1380 
1381 	return 0;
1382 }
1383 
1384 int
1385 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
1386 {
1387 	if (!pci_dma_supported(dev, mask))
1388 		return -EIO;
1389 
1390 	dev->dev.coherent_dma_mask = mask;
1391 
1392 	return 0;
1393 }
1394 #endif
1395 
1396 /**
1397  * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
1398  * @dev: PCI device to query
1399  *
1400  * Returns mmrbc: maximum designed memory read count in bytes
1401  *    or appropriate error value.
1402  */
1403 int pcix_get_max_mmrbc(struct pci_dev *dev)
1404 {
1405 	int err, cap;
1406 	u32 stat;
1407 
1408 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1409 	if (!cap)
1410 		return -EINVAL;
1411 
1412 	err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
1413 	if (err)
1414 		return -EINVAL;
1415 
1416 	return (stat & PCI_X_STATUS_MAX_READ) >> 12;
1417 }
1418 EXPORT_SYMBOL(pcix_get_max_mmrbc);
1419 
1420 /**
1421  * pcix_get_mmrbc - get PCI-X maximum memory read byte count
1422  * @dev: PCI device to query
1423  *
1424  * Returns mmrbc: maximum memory read count in bytes
1425  *    or appropriate error value.
1426  */
1427 int pcix_get_mmrbc(struct pci_dev *dev)
1428 {
1429 	int ret, cap;
1430 	u32 cmd;
1431 
1432 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1433 	if (!cap)
1434 		return -EINVAL;
1435 
1436 	ret = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
1437 	if (!ret)
1438 		ret = 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
1439 
1440 	return ret;
1441 }
1442 EXPORT_SYMBOL(pcix_get_mmrbc);
1443 
1444 /**
1445  * pcix_set_mmrbc - set PCI-X maximum memory read byte count
1446  * @dev: PCI device to query
1447  * @mmrbc: maximum memory read count in bytes
1448  *    valid values are 512, 1024, 2048, 4096
1449  *
1450  * If possible sets maximum memory read byte count, some bridges have erratas
1451  * that prevent this.
1452  */
1453 int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
1454 {
1455 	int cap, err = -EINVAL;
1456 	u32 stat, cmd, v, o;
1457 
1458 	if (mmrbc < 512 || mmrbc > 4096 || (mmrbc & (mmrbc-1)))
1459 		goto out;
1460 
1461 	v = ffs(mmrbc) - 10;
1462 
1463 	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1464 	if (!cap)
1465 		goto out;
1466 
1467 	err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
1468 	if (err)
1469 		goto out;
1470 
1471 	if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
1472 		return -E2BIG;
1473 
1474 	err = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
1475 	if (err)
1476 		goto out;
1477 
1478 	o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
1479 	if (o != v) {
1480 		if (v > o && dev->bus &&
1481 		   (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
1482 			return -EIO;
1483 
1484 		cmd &= ~PCI_X_CMD_MAX_READ;
1485 		cmd |= v << 2;
1486 		err = pci_write_config_dword(dev, cap + PCI_X_CMD, cmd);
1487 	}
1488 out:
1489 	return err;
1490 }
1491 EXPORT_SYMBOL(pcix_set_mmrbc);
1492 
1493 /**
1494  * pcie_get_readrq - get PCI Express read request size
1495  * @dev: PCI device to query
1496  *
1497  * Returns maximum memory read request in bytes
1498  *    or appropriate error value.
1499  */
1500 int pcie_get_readrq(struct pci_dev *dev)
1501 {
1502 	int ret, cap;
1503 	u16 ctl;
1504 
1505 	cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
1506 	if (!cap)
1507 		return -EINVAL;
1508 
1509 	ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
1510 	if (!ret)
1511 	ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
1512 
1513 	return ret;
1514 }
1515 EXPORT_SYMBOL(pcie_get_readrq);
1516 
1517 /**
1518  * pcie_set_readrq - set PCI Express maximum memory read request
1519  * @dev: PCI device to query
1520  * @rq: maximum memory read count in bytes
1521  *    valid values are 128, 256, 512, 1024, 2048, 4096
1522  *
1523  * If possible sets maximum read byte count
1524  */
1525 int pcie_set_readrq(struct pci_dev *dev, int rq)
1526 {
1527 	int cap, err = -EINVAL;
1528 	u16 ctl, v;
1529 
1530 	if (rq < 128 || rq > 4096 || (rq & (rq-1)))
1531 		goto out;
1532 
1533 	v = (ffs(rq) - 8) << 12;
1534 
1535 	cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
1536 	if (!cap)
1537 		goto out;
1538 
1539 	err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
1540 	if (err)
1541 		goto out;
1542 
1543 	if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
1544 		ctl &= ~PCI_EXP_DEVCTL_READRQ;
1545 		ctl |= v;
1546 		err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
1547 	}
1548 
1549 out:
1550 	return err;
1551 }
1552 EXPORT_SYMBOL(pcie_set_readrq);
1553 
1554 /**
1555  * pci_select_bars - Make BAR mask from the type of resource
1556  * @dev: the PCI device for which BAR mask is made
1557  * @flags: resource type mask to be selected
1558  *
1559  * This helper routine makes bar mask from the type of resource.
1560  */
1561 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
1562 {
1563 	int i, bars = 0;
1564 	for (i = 0; i < PCI_NUM_RESOURCES; i++)
1565 		if (pci_resource_flags(dev, i) & flags)
1566 			bars |= (1 << i);
1567 	return bars;
1568 }
1569 
1570 static int __devinit pci_init(void)
1571 {
1572 	struct pci_dev *dev = NULL;
1573 
1574 	while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
1575 		pci_fixup_device(pci_fixup_final, dev);
1576 	}
1577 	return 0;
1578 }
1579 
1580 static int __devinit pci_setup(char *str)
1581 {
1582 	while (str) {
1583 		char *k = strchr(str, ',');
1584 		if (k)
1585 			*k++ = 0;
1586 		if (*str && (str = pcibios_setup(str)) && *str) {
1587 			if (!strcmp(str, "nomsi")) {
1588 				pci_no_msi();
1589 			} else if (!strncmp(str, "cbiosize=", 9)) {
1590 				pci_cardbus_io_size = memparse(str + 9, &str);
1591 			} else if (!strncmp(str, "cbmemsize=", 10)) {
1592 				pci_cardbus_mem_size = memparse(str + 10, &str);
1593 			} else {
1594 				printk(KERN_ERR "PCI: Unknown option `%s'\n",
1595 						str);
1596 			}
1597 		}
1598 		str = k;
1599 	}
1600 	return 0;
1601 }
1602 early_param("pci", pci_setup);
1603 
1604 device_initcall(pci_init);
1605 
1606 EXPORT_SYMBOL_GPL(pci_restore_bars);
1607 EXPORT_SYMBOL(__pci_reenable_device);
1608 EXPORT_SYMBOL(pci_enable_device_bars);
1609 EXPORT_SYMBOL(pci_enable_device);
1610 EXPORT_SYMBOL(pcim_enable_device);
1611 EXPORT_SYMBOL(pcim_pin_device);
1612 EXPORT_SYMBOL(pci_disable_device);
1613 EXPORT_SYMBOL(pci_find_capability);
1614 EXPORT_SYMBOL(pci_bus_find_capability);
1615 EXPORT_SYMBOL(pci_release_regions);
1616 EXPORT_SYMBOL(pci_request_regions);
1617 EXPORT_SYMBOL(pci_release_region);
1618 EXPORT_SYMBOL(pci_request_region);
1619 EXPORT_SYMBOL(pci_release_selected_regions);
1620 EXPORT_SYMBOL(pci_request_selected_regions);
1621 EXPORT_SYMBOL(pci_set_master);
1622 EXPORT_SYMBOL(pci_set_mwi);
1623 EXPORT_SYMBOL(pci_try_set_mwi);
1624 EXPORT_SYMBOL(pci_clear_mwi);
1625 EXPORT_SYMBOL_GPL(pci_intx);
1626 EXPORT_SYMBOL(pci_set_dma_mask);
1627 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
1628 EXPORT_SYMBOL(pci_assign_resource);
1629 EXPORT_SYMBOL(pci_find_parent_resource);
1630 EXPORT_SYMBOL(pci_select_bars);
1631 
1632 EXPORT_SYMBOL(pci_set_power_state);
1633 EXPORT_SYMBOL(pci_save_state);
1634 EXPORT_SYMBOL(pci_restore_state);
1635 EXPORT_SYMBOL(pci_enable_wake);
1636 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
1637 
1638