PCI PM: Read power state from device after trying to change it on resume
[linux-2.6/verdex.git] / drivers / pci / pci.c
blobe3efe6b19ee79210e2885f03b1d21995e2125abb
1 /*
2 * PCI Bus Services, see include/linux/pci.h for further explanation.
4 * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
5 * David Mosberger-Tang
7 * Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
8 */
10 #include <linux/kernel.h>
11 #include <linux/delay.h>
12 #include <linux/init.h>
13 #include <linux/pci.h>
14 #include <linux/pm.h>
15 #include <linux/module.h>
16 #include <linux/spinlock.h>
17 #include <linux/string.h>
18 #include <linux/log2.h>
19 #include <linux/pci-aspm.h>
20 #include <linux/pm_wakeup.h>
21 #include <linux/interrupt.h>
22 #include <asm/dma.h> /* isa_dma_bridge_buggy */
23 #include "pci.h"
25 unsigned int pci_pm_d3_delay = PCI_PM_D3_WAIT;
27 #ifdef CONFIG_PCI_DOMAINS
28 int pci_domains_supported = 1;
29 #endif
31 #define DEFAULT_CARDBUS_IO_SIZE (256)
32 #define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
33 /* pci=cbmemsize=nnM,cbiosize=nn can override this */
34 unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
35 unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
37 /**
38 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
39 * @bus: pointer to PCI bus structure to search
41 * Given a PCI bus, returns the highest PCI bus number present in the set
42 * including the given PCI bus and its list of child PCI buses.
44 unsigned char pci_bus_max_busnr(struct pci_bus* bus)
46 struct list_head *tmp;
47 unsigned char max, n;
49 max = bus->subordinate;
50 list_for_each(tmp, &bus->children) {
51 n = pci_bus_max_busnr(pci_bus_b(tmp));
52 if(n > max)
53 max = n;
55 return max;
57 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
59 #ifdef CONFIG_HAS_IOMEM
60 void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
63 * Make sure the BAR is actually a memory resource, not an IO resource
65 if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
66 WARN_ON(1);
67 return NULL;
69 return ioremap_nocache(pci_resource_start(pdev, bar),
70 pci_resource_len(pdev, bar));
72 EXPORT_SYMBOL_GPL(pci_ioremap_bar);
73 #endif
75 #if 0
76 /**
77 * pci_max_busnr - returns maximum PCI bus number
79 * Returns the highest PCI bus number present in the system global list of
80 * PCI buses.
82 unsigned char __devinit
83 pci_max_busnr(void)
85 struct pci_bus *bus = NULL;
86 unsigned char max, n;
88 max = 0;
89 while ((bus = pci_find_next_bus(bus)) != NULL) {
90 n = pci_bus_max_busnr(bus);
91 if(n > max)
92 max = n;
94 return max;
97 #endif /* 0 */
99 #define PCI_FIND_CAP_TTL 48
101 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
102 u8 pos, int cap, int *ttl)
104 u8 id;
106 while ((*ttl)--) {
107 pci_bus_read_config_byte(bus, devfn, pos, &pos);
108 if (pos < 0x40)
109 break;
110 pos &= ~3;
111 pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
112 &id);
113 if (id == 0xff)
114 break;
115 if (id == cap)
116 return pos;
117 pos += PCI_CAP_LIST_NEXT;
119 return 0;
122 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
123 u8 pos, int cap)
125 int ttl = PCI_FIND_CAP_TTL;
127 return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
130 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
132 return __pci_find_next_cap(dev->bus, dev->devfn,
133 pos + PCI_CAP_LIST_NEXT, cap);
135 EXPORT_SYMBOL_GPL(pci_find_next_capability);
137 static int __pci_bus_find_cap_start(struct pci_bus *bus,
138 unsigned int devfn, u8 hdr_type)
140 u16 status;
142 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
143 if (!(status & PCI_STATUS_CAP_LIST))
144 return 0;
146 switch (hdr_type) {
147 case PCI_HEADER_TYPE_NORMAL:
148 case PCI_HEADER_TYPE_BRIDGE:
149 return PCI_CAPABILITY_LIST;
150 case PCI_HEADER_TYPE_CARDBUS:
151 return PCI_CB_CAPABILITY_LIST;
152 default:
153 return 0;
156 return 0;
160 * pci_find_capability - query for devices' capabilities
161 * @dev: PCI device to query
162 * @cap: capability code
164 * Tell if a device supports a given PCI capability.
165 * Returns the address of the requested capability structure within the
166 * device's PCI configuration space or 0 in case the device does not
167 * support it. Possible values for @cap:
169 * %PCI_CAP_ID_PM Power Management
170 * %PCI_CAP_ID_AGP Accelerated Graphics Port
171 * %PCI_CAP_ID_VPD Vital Product Data
172 * %PCI_CAP_ID_SLOTID Slot Identification
173 * %PCI_CAP_ID_MSI Message Signalled Interrupts
174 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
175 * %PCI_CAP_ID_PCIX PCI-X
176 * %PCI_CAP_ID_EXP PCI Express
178 int pci_find_capability(struct pci_dev *dev, int cap)
180 int pos;
182 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
183 if (pos)
184 pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
186 return pos;
190 * pci_bus_find_capability - query for devices' capabilities
191 * @bus: the PCI bus to query
192 * @devfn: PCI device to query
193 * @cap: capability code
195 * Like pci_find_capability() but works for pci devices that do not have a
196 * pci_dev structure set up yet.
198 * Returns the address of the requested capability structure within the
199 * device's PCI configuration space or 0 in case the device does not
200 * support it.
202 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
204 int pos;
205 u8 hdr_type;
207 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
209 pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
210 if (pos)
211 pos = __pci_find_next_cap(bus, devfn, pos, cap);
213 return pos;
217 * pci_find_ext_capability - Find an extended capability
218 * @dev: PCI device to query
219 * @cap: capability code
221 * Returns the address of the requested extended capability structure
222 * within the device's PCI configuration space or 0 if the device does
223 * not support it. Possible values for @cap:
225 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
226 * %PCI_EXT_CAP_ID_VC Virtual Channel
227 * %PCI_EXT_CAP_ID_DSN Device Serial Number
228 * %PCI_EXT_CAP_ID_PWR Power Budgeting
230 int pci_find_ext_capability(struct pci_dev *dev, int cap)
232 u32 header;
233 int ttl;
234 int pos = PCI_CFG_SPACE_SIZE;
236 /* minimum 8 bytes per capability */
237 ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
239 if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
240 return 0;
242 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
243 return 0;
246 * If we have no capabilities, this is indicated by cap ID,
247 * cap version and next pointer all being 0.
249 if (header == 0)
250 return 0;
252 while (ttl-- > 0) {
253 if (PCI_EXT_CAP_ID(header) == cap)
254 return pos;
256 pos = PCI_EXT_CAP_NEXT(header);
257 if (pos < PCI_CFG_SPACE_SIZE)
258 break;
260 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
261 break;
264 return 0;
266 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
268 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
270 int rc, ttl = PCI_FIND_CAP_TTL;
271 u8 cap, mask;
273 if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
274 mask = HT_3BIT_CAP_MASK;
275 else
276 mask = HT_5BIT_CAP_MASK;
278 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
279 PCI_CAP_ID_HT, &ttl);
280 while (pos) {
281 rc = pci_read_config_byte(dev, pos + 3, &cap);
282 if (rc != PCIBIOS_SUCCESSFUL)
283 return 0;
285 if ((cap & mask) == ht_cap)
286 return pos;
288 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
289 pos + PCI_CAP_LIST_NEXT,
290 PCI_CAP_ID_HT, &ttl);
293 return 0;
296 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
297 * @dev: PCI device to query
298 * @pos: Position from which to continue searching
299 * @ht_cap: Hypertransport capability code
301 * To be used in conjunction with pci_find_ht_capability() to search for
302 * all capabilities matching @ht_cap. @pos should always be a value returned
303 * from pci_find_ht_capability().
305 * NB. To be 100% safe against broken PCI devices, the caller should take
306 * steps to avoid an infinite loop.
308 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
310 return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
312 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
315 * pci_find_ht_capability - query a device's Hypertransport capabilities
316 * @dev: PCI device to query
317 * @ht_cap: Hypertransport capability code
319 * Tell if a device supports a given Hypertransport capability.
320 * Returns an address within the device's PCI configuration space
321 * or 0 in case the device does not support the request capability.
322 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
323 * which has a Hypertransport capability matching @ht_cap.
325 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
327 int pos;
329 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
330 if (pos)
331 pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
333 return pos;
335 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
338 * pci_find_parent_resource - return resource region of parent bus of given region
339 * @dev: PCI device structure contains resources to be searched
340 * @res: child resource record for which parent is sought
342 * For given resource region of given device, return the resource
343 * region of parent bus the given region is contained in or where
344 * it should be allocated from.
346 struct resource *
347 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
349 const struct pci_bus *bus = dev->bus;
350 int i;
351 struct resource *best = NULL;
353 for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
354 struct resource *r = bus->resource[i];
355 if (!r)
356 continue;
357 if (res->start && !(res->start >= r->start && res->end <= r->end))
358 continue; /* Not contained */
359 if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
360 continue; /* Wrong type */
361 if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
362 return r; /* Exact match */
363 if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
364 best = r; /* Approximating prefetchable by non-prefetchable */
366 return best;
370 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
371 * @dev: PCI device to have its BARs restored
373 * Restore the BAR values for a given device, so as to make it
374 * accessible by its driver.
376 static void
377 pci_restore_bars(struct pci_dev *dev)
379 int i;
381 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
382 pci_update_resource(dev, i);
385 static struct pci_platform_pm_ops *pci_platform_pm;
387 int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
389 if (!ops->is_manageable || !ops->set_state || !ops->choose_state
390 || !ops->sleep_wake || !ops->can_wakeup)
391 return -EINVAL;
392 pci_platform_pm = ops;
393 return 0;
396 static inline bool platform_pci_power_manageable(struct pci_dev *dev)
398 return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
401 static inline int platform_pci_set_power_state(struct pci_dev *dev,
402 pci_power_t t)
404 return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
407 static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
409 return pci_platform_pm ?
410 pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
413 static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
415 return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
418 static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
420 return pci_platform_pm ?
421 pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
425 * pci_raw_set_power_state - Use PCI PM registers to set the power state of
426 * given PCI device
427 * @dev: PCI device to handle.
428 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
429 * @wait: If 'true', wait for the device to change its power state
431 * RETURN VALUE:
432 * -EINVAL if the requested state is invalid.
433 * -EIO if device does not support PCI PM or its PM capabilities register has a
434 * wrong version, or device doesn't support the requested state.
435 * 0 if device already is in the requested state.
436 * 0 if device's power state has been successfully changed.
438 static int
439 pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state, bool wait)
441 u16 pmcsr;
442 bool need_restore = false;
444 if (!dev->pm_cap)
445 return -EIO;
447 if (state < PCI_D0 || state > PCI_D3hot)
448 return -EINVAL;
450 /* Validate current state:
451 * Can enter D0 from any state, but if we can only go deeper
452 * to sleep if we're already in a low power state
454 if (dev->current_state == state) {
455 /* we're already there */
456 return 0;
457 } else if (state != PCI_D0 && dev->current_state <= PCI_D3cold
458 && dev->current_state > state) {
459 dev_err(&dev->dev, "invalid power transition "
460 "(from state %d to %d)\n", dev->current_state, state);
461 return -EINVAL;
464 /* check if this device supports the desired state */
465 if ((state == PCI_D1 && !dev->d1_support)
466 || (state == PCI_D2 && !dev->d2_support))
467 return -EIO;
469 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
471 /* If we're (effectively) in D3, force entire word to 0.
472 * This doesn't affect PME_Status, disables PME_En, and
473 * sets PowerState to 0.
475 switch (dev->current_state) {
476 case PCI_D0:
477 case PCI_D1:
478 case PCI_D2:
479 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
480 pmcsr |= state;
481 break;
482 case PCI_UNKNOWN: /* Boot-up */
483 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
484 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET)) {
485 need_restore = true;
486 wait = true;
488 /* Fall-through: force to D0 */
489 default:
490 pmcsr = 0;
491 break;
494 /* enter specified state */
495 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
497 if (!wait)
498 return 0;
500 /* Mandatory power management transition delays */
501 /* see PCI PM 1.1 5.6.1 table 18 */
502 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
503 msleep(pci_pm_d3_delay);
504 else if (state == PCI_D2 || dev->current_state == PCI_D2)
505 udelay(PCI_PM_D2_DELAY);
507 dev->current_state = state;
509 /* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
510 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
511 * from D3hot to D0 _may_ perform an internal reset, thereby
512 * going to "D0 Uninitialized" rather than "D0 Initialized".
513 * For example, at least some versions of the 3c905B and the
514 * 3c556B exhibit this behaviour.
516 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
517 * devices in a D3hot state at boot. Consequently, we need to
518 * restore at least the BARs so that the device will be
519 * accessible to its driver.
521 if (need_restore)
522 pci_restore_bars(dev);
524 if (wait && dev->bus->self)
525 pcie_aspm_pm_state_change(dev->bus->self);
527 return 0;
531 * pci_update_current_state - Read PCI power state of given device from its
532 * PCI PM registers and cache it
533 * @dev: PCI device to handle.
534 * @state: State to cache in case the device doesn't have the PM capability
536 void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
538 if (dev->pm_cap) {
539 u16 pmcsr;
541 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
542 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
543 } else {
544 dev->current_state = state;
549 * pci_set_power_state - Set the power state of a PCI device
550 * @dev: PCI device to handle.
551 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
553 * Transition a device to a new power state, using the platform formware and/or
554 * the device's PCI PM registers.
556 * RETURN VALUE:
557 * -EINVAL if the requested state is invalid.
558 * -EIO if device does not support PCI PM or its PM capabilities register has a
559 * wrong version, or device doesn't support the requested state.
560 * 0 if device already is in the requested state.
561 * 0 if device's power state has been successfully changed.
563 int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
565 int error;
567 /* bound the state we're entering */
568 if (state > PCI_D3hot)
569 state = PCI_D3hot;
570 else if (state < PCI_D0)
571 state = PCI_D0;
572 else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
574 * If the device or the parent bridge do not support PCI PM,
575 * ignore the request if we're doing anything other than putting
576 * it into D0 (which would only happen on boot).
578 return 0;
580 if (state == PCI_D0 && platform_pci_power_manageable(dev)) {
582 * Allow the platform to change the state, for example via ACPI
583 * _PR0, _PS0 and some such, but do not trust it.
585 int ret = platform_pci_set_power_state(dev, PCI_D0);
586 if (!ret)
587 pci_update_current_state(dev, PCI_D0);
589 /* This device is quirked not to be put into D3, so
590 don't put it in D3 */
591 if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
592 return 0;
594 error = pci_raw_set_power_state(dev, state, true);
596 if (state > PCI_D0 && platform_pci_power_manageable(dev)) {
597 /* Allow the platform to finalize the transition */
598 int ret = platform_pci_set_power_state(dev, state);
599 if (!ret) {
600 pci_update_current_state(dev, state);
601 error = 0;
605 return error;
609 * pci_choose_state - Choose the power state of a PCI device
610 * @dev: PCI device to be suspended
611 * @state: target sleep state for the whole system. This is the value
612 * that is passed to suspend() function.
614 * Returns PCI power state suitable for given device and given system
615 * message.
618 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
620 pci_power_t ret;
622 if (!pci_find_capability(dev, PCI_CAP_ID_PM))
623 return PCI_D0;
625 ret = platform_pci_choose_state(dev);
626 if (ret != PCI_POWER_ERROR)
627 return ret;
629 switch (state.event) {
630 case PM_EVENT_ON:
631 return PCI_D0;
632 case PM_EVENT_FREEZE:
633 case PM_EVENT_PRETHAW:
634 /* REVISIT both freeze and pre-thaw "should" use D0 */
635 case PM_EVENT_SUSPEND:
636 case PM_EVENT_HIBERNATE:
637 return PCI_D3hot;
638 default:
639 dev_info(&dev->dev, "unrecognized suspend event %d\n",
640 state.event);
641 BUG();
643 return PCI_D0;
646 EXPORT_SYMBOL(pci_choose_state);
648 static int pci_save_pcie_state(struct pci_dev *dev)
650 int pos, i = 0;
651 struct pci_cap_saved_state *save_state;
652 u16 *cap;
654 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
655 if (pos <= 0)
656 return 0;
658 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
659 if (!save_state) {
660 dev_err(&dev->dev, "buffer not found in %s\n", __FUNCTION__);
661 return -ENOMEM;
663 cap = (u16 *)&save_state->data[0];
665 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
666 pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
667 pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
668 pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
670 return 0;
673 static void pci_restore_pcie_state(struct pci_dev *dev)
675 int i = 0, pos;
676 struct pci_cap_saved_state *save_state;
677 u16 *cap;
679 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
680 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
681 if (!save_state || pos <= 0)
682 return;
683 cap = (u16 *)&save_state->data[0];
685 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
686 pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
687 pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
688 pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
692 static int pci_save_pcix_state(struct pci_dev *dev)
694 int pos;
695 struct pci_cap_saved_state *save_state;
697 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
698 if (pos <= 0)
699 return 0;
701 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
702 if (!save_state) {
703 dev_err(&dev->dev, "buffer not found in %s\n", __FUNCTION__);
704 return -ENOMEM;
707 pci_read_config_word(dev, pos + PCI_X_CMD, (u16 *)save_state->data);
709 return 0;
712 static void pci_restore_pcix_state(struct pci_dev *dev)
714 int i = 0, pos;
715 struct pci_cap_saved_state *save_state;
716 u16 *cap;
718 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
719 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
720 if (!save_state || pos <= 0)
721 return;
722 cap = (u16 *)&save_state->data[0];
724 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
729 * pci_save_state - save the PCI configuration space of a device before suspending
730 * @dev: - PCI device that we're dealing with
733 pci_save_state(struct pci_dev *dev)
735 int i;
736 /* XXX: 100% dword access ok here? */
737 for (i = 0; i < 16; i++)
738 pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
739 dev->state_saved = true;
740 if ((i = pci_save_pcie_state(dev)) != 0)
741 return i;
742 if ((i = pci_save_pcix_state(dev)) != 0)
743 return i;
744 return 0;
747 /**
748 * pci_restore_state - Restore the saved state of a PCI device
749 * @dev: - PCI device that we're dealing with
751 int
752 pci_restore_state(struct pci_dev *dev)
754 int i;
755 u32 val;
757 /* PCI Express register must be restored first */
758 pci_restore_pcie_state(dev);
761 * The Base Address register should be programmed before the command
762 * register(s)
764 for (i = 15; i >= 0; i--) {
765 pci_read_config_dword(dev, i * 4, &val);
766 if (val != dev->saved_config_space[i]) {
767 dev_printk(KERN_DEBUG, &dev->dev, "restoring config "
768 "space at offset %#x (was %#x, writing %#x)\n",
769 i, val, (int)dev->saved_config_space[i]);
770 pci_write_config_dword(dev,i * 4,
771 dev->saved_config_space[i]);
774 pci_restore_pcix_state(dev);
775 pci_restore_msi_state(dev);
777 return 0;
780 static int do_pci_enable_device(struct pci_dev *dev, int bars)
782 int err;
784 err = pci_set_power_state(dev, PCI_D0);
785 if (err < 0 && err != -EIO)
786 return err;
787 err = pcibios_enable_device(dev, bars);
788 if (err < 0)
789 return err;
790 pci_fixup_device(pci_fixup_enable, dev);
792 return 0;
796 * pci_reenable_device - Resume abandoned device
797 * @dev: PCI device to be resumed
799 * Note this function is a backend of pci_default_resume and is not supposed
800 * to be called by normal code, write proper resume handler and use it instead.
802 int pci_reenable_device(struct pci_dev *dev)
804 if (atomic_read(&dev->enable_cnt))
805 return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
806 return 0;
809 static int __pci_enable_device_flags(struct pci_dev *dev,
810 resource_size_t flags)
812 int err;
813 int i, bars = 0;
815 if (atomic_add_return(1, &dev->enable_cnt) > 1)
816 return 0; /* already enabled */
818 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
819 if (dev->resource[i].flags & flags)
820 bars |= (1 << i);
822 err = do_pci_enable_device(dev, bars);
823 if (err < 0)
824 atomic_dec(&dev->enable_cnt);
825 return err;
829 * pci_enable_device_io - Initialize a device for use with IO space
830 * @dev: PCI device to be initialized
832 * Initialize device before it's used by a driver. Ask low-level code
833 * to enable I/O resources. Wake up the device if it was suspended.
834 * Beware, this function can fail.
836 int pci_enable_device_io(struct pci_dev *dev)
838 return __pci_enable_device_flags(dev, IORESOURCE_IO);
842 * pci_enable_device_mem - Initialize a device for use with Memory space
843 * @dev: PCI device to be initialized
845 * Initialize device before it's used by a driver. Ask low-level code
846 * to enable Memory resources. Wake up the device if it was suspended.
847 * Beware, this function can fail.
849 int pci_enable_device_mem(struct pci_dev *dev)
851 return __pci_enable_device_flags(dev, IORESOURCE_MEM);
855 * pci_enable_device - Initialize device before it's used by a driver.
856 * @dev: PCI device to be initialized
858 * Initialize device before it's used by a driver. Ask low-level code
859 * to enable I/O and memory. Wake up the device if it was suspended.
860 * Beware, this function can fail.
862 * Note we don't actually enable the device many times if we call
863 * this function repeatedly (we just increment the count).
865 int pci_enable_device(struct pci_dev *dev)
867 return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
871 * Managed PCI resources. This manages device on/off, intx/msi/msix
872 * on/off and BAR regions. pci_dev itself records msi/msix status, so
873 * there's no need to track it separately. pci_devres is initialized
874 * when a device is enabled using managed PCI device enable interface.
876 struct pci_devres {
877 unsigned int enabled:1;
878 unsigned int pinned:1;
879 unsigned int orig_intx:1;
880 unsigned int restore_intx:1;
881 u32 region_mask;
884 static void pcim_release(struct device *gendev, void *res)
886 struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
887 struct pci_devres *this = res;
888 int i;
890 if (dev->msi_enabled)
891 pci_disable_msi(dev);
892 if (dev->msix_enabled)
893 pci_disable_msix(dev);
895 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
896 if (this->region_mask & (1 << i))
897 pci_release_region(dev, i);
899 if (this->restore_intx)
900 pci_intx(dev, this->orig_intx);
902 if (this->enabled && !this->pinned)
903 pci_disable_device(dev);
906 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
908 struct pci_devres *dr, *new_dr;
910 dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
911 if (dr)
912 return dr;
914 new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
915 if (!new_dr)
916 return NULL;
917 return devres_get(&pdev->dev, new_dr, NULL, NULL);
920 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
922 if (pci_is_managed(pdev))
923 return devres_find(&pdev->dev, pcim_release, NULL, NULL);
924 return NULL;
928 * pcim_enable_device - Managed pci_enable_device()
929 * @pdev: PCI device to be initialized
931 * Managed pci_enable_device().
933 int pcim_enable_device(struct pci_dev *pdev)
935 struct pci_devres *dr;
936 int rc;
938 dr = get_pci_dr(pdev);
939 if (unlikely(!dr))
940 return -ENOMEM;
941 if (dr->enabled)
942 return 0;
944 rc = pci_enable_device(pdev);
945 if (!rc) {
946 pdev->is_managed = 1;
947 dr->enabled = 1;
949 return rc;
953 * pcim_pin_device - Pin managed PCI device
954 * @pdev: PCI device to pin
956 * Pin managed PCI device @pdev. Pinned device won't be disabled on
957 * driver detach. @pdev must have been enabled with
958 * pcim_enable_device().
960 void pcim_pin_device(struct pci_dev *pdev)
962 struct pci_devres *dr;
964 dr = find_pci_dr(pdev);
965 WARN_ON(!dr || !dr->enabled);
966 if (dr)
967 dr->pinned = 1;
971 * pcibios_disable_device - disable arch specific PCI resources for device dev
972 * @dev: the PCI device to disable
974 * Disables architecture specific PCI resources for the device. This
975 * is the default implementation. Architecture implementations can
976 * override this.
978 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
980 static void do_pci_disable_device(struct pci_dev *dev)
982 u16 pci_command;
984 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
985 if (pci_command & PCI_COMMAND_MASTER) {
986 pci_command &= ~PCI_COMMAND_MASTER;
987 pci_write_config_word(dev, PCI_COMMAND, pci_command);
990 pcibios_disable_device(dev);
994 * pci_disable_enabled_device - Disable device without updating enable_cnt
995 * @dev: PCI device to disable
997 * NOTE: This function is a backend of PCI power management routines and is
998 * not supposed to be called drivers.
1000 void pci_disable_enabled_device(struct pci_dev *dev)
1002 if (atomic_read(&dev->enable_cnt))
1003 do_pci_disable_device(dev);
1007 * pci_disable_device - Disable PCI device after use
1008 * @dev: PCI device to be disabled
1010 * Signal to the system that the PCI device is not in use by the system
1011 * anymore. This only involves disabling PCI bus-mastering, if active.
1013 * Note we don't actually disable the device until all callers of
1014 * pci_device_enable() have called pci_device_disable().
1016 void
1017 pci_disable_device(struct pci_dev *dev)
1019 struct pci_devres *dr;
1021 dr = find_pci_dr(dev);
1022 if (dr)
1023 dr->enabled = 0;
1025 if (atomic_sub_return(1, &dev->enable_cnt) != 0)
1026 return;
1028 do_pci_disable_device(dev);
1030 dev->is_busmaster = 0;
1034 * pcibios_set_pcie_reset_state - set reset state for device dev
1035 * @dev: the PCI-E device reset
1036 * @state: Reset state to enter into
1039 * Sets the PCI-E reset state for the device. This is the default
1040 * implementation. Architecture implementations can override this.
1042 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
1043 enum pcie_reset_state state)
1045 return -EINVAL;
1049 * pci_set_pcie_reset_state - set reset state for device dev
1050 * @dev: the PCI-E device reset
1051 * @state: Reset state to enter into
1054 * Sets the PCI reset state for the device.
1056 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1058 return pcibios_set_pcie_reset_state(dev, state);
1062 * pci_pme_capable - check the capability of PCI device to generate PME#
1063 * @dev: PCI device to handle.
1064 * @state: PCI state from which device will issue PME#.
1066 bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1068 if (!dev->pm_cap)
1069 return false;
1071 return !!(dev->pme_support & (1 << state));
1075 * pci_pme_active - enable or disable PCI device's PME# function
1076 * @dev: PCI device to handle.
1077 * @enable: 'true' to enable PME# generation; 'false' to disable it.
1079 * The caller must verify that the device is capable of generating PME# before
1080 * calling this function with @enable equal to 'true'.
1082 void pci_pme_active(struct pci_dev *dev, bool enable)
1084 u16 pmcsr;
1086 if (!dev->pm_cap)
1087 return;
1089 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1090 /* Clear PME_Status by writing 1 to it and enable PME# */
1091 pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1092 if (!enable)
1093 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1095 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1097 dev_printk(KERN_INFO, &dev->dev, "PME# %s\n",
1098 enable ? "enabled" : "disabled");
1102 * pci_enable_wake - enable PCI device as wakeup event source
1103 * @dev: PCI device affected
1104 * @state: PCI state from which device will issue wakeup events
1105 * @enable: True to enable event generation; false to disable
1107 * This enables the device as a wakeup event source, or disables it.
1108 * When such events involves platform-specific hooks, those hooks are
1109 * called automatically by this routine.
1111 * Devices with legacy power management (no standard PCI PM capabilities)
1112 * always require such platform hooks.
1114 * RETURN VALUE:
1115 * 0 is returned on success
1116 * -EINVAL is returned if device is not supposed to wake up the system
1117 * Error code depending on the platform is returned if both the platform and
1118 * the native mechanism fail to enable the generation of wake-up events
1120 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
1122 int error = 0;
1123 bool pme_done = false;
1125 if (enable && !device_may_wakeup(&dev->dev))
1126 return -EINVAL;
1129 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1130 * Anderson we should be doing PME# wake enable followed by ACPI wake
1131 * enable. To disable wake-up we call the platform first, for symmetry.
1134 if (!enable && platform_pci_can_wakeup(dev))
1135 error = platform_pci_sleep_wake(dev, false);
1137 if (!enable || pci_pme_capable(dev, state)) {
1138 pci_pme_active(dev, enable);
1139 pme_done = true;
1142 if (enable && platform_pci_can_wakeup(dev))
1143 error = platform_pci_sleep_wake(dev, true);
1145 return pme_done ? 0 : error;
1149 * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1150 * @dev: PCI device to prepare
1151 * @enable: True to enable wake-up event generation; false to disable
1153 * Many drivers want the device to wake up the system from D3_hot or D3_cold
1154 * and this function allows them to set that up cleanly - pci_enable_wake()
1155 * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1156 * ordering constraints.
1158 * This function only returns error code if the device is not capable of
1159 * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1160 * enable wake-up power for it.
1162 int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1164 return pci_pme_capable(dev, PCI_D3cold) ?
1165 pci_enable_wake(dev, PCI_D3cold, enable) :
1166 pci_enable_wake(dev, PCI_D3hot, enable);
1170 * pci_target_state - find an appropriate low power state for a given PCI dev
1171 * @dev: PCI device
1173 * Use underlying platform code to find a supported low power state for @dev.
1174 * If the platform can't manage @dev, return the deepest state from which it
1175 * can generate wake events, based on any available PME info.
1177 pci_power_t pci_target_state(struct pci_dev *dev)
1179 pci_power_t target_state = PCI_D3hot;
1181 if (platform_pci_power_manageable(dev)) {
1183 * Call the platform to choose the target state of the device
1184 * and enable wake-up from this state if supported.
1186 pci_power_t state = platform_pci_choose_state(dev);
1188 switch (state) {
1189 case PCI_POWER_ERROR:
1190 case PCI_UNKNOWN:
1191 break;
1192 case PCI_D1:
1193 case PCI_D2:
1194 if (pci_no_d1d2(dev))
1195 break;
1196 default:
1197 target_state = state;
1199 } else if (device_may_wakeup(&dev->dev)) {
1201 * Find the deepest state from which the device can generate
1202 * wake-up events, make it the target state and enable device
1203 * to generate PME#.
1205 if (!dev->pm_cap)
1206 return PCI_POWER_ERROR;
1208 if (dev->pme_support) {
1209 while (target_state
1210 && !(dev->pme_support & (1 << target_state)))
1211 target_state--;
1215 return target_state;
1219 * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1220 * @dev: Device to handle.
1222 * Choose the power state appropriate for the device depending on whether
1223 * it can wake up the system and/or is power manageable by the platform
1224 * (PCI_D3hot is the default) and put the device into that state.
1226 int pci_prepare_to_sleep(struct pci_dev *dev)
1228 pci_power_t target_state = pci_target_state(dev);
1229 int error;
1231 if (target_state == PCI_POWER_ERROR)
1232 return -EIO;
1234 pci_enable_wake(dev, target_state, true);
1236 error = pci_set_power_state(dev, target_state);
1238 if (error)
1239 pci_enable_wake(dev, target_state, false);
1241 return error;
1245 * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1246 * @dev: Device to handle.
1248 * Disable device's sytem wake-up capability and put it into D0.
1250 int pci_back_from_sleep(struct pci_dev *dev)
1252 pci_enable_wake(dev, PCI_D0, false);
1253 return pci_set_power_state(dev, PCI_D0);
1257 * pci_pm_init - Initialize PM functions of given PCI device
1258 * @dev: PCI device to handle.
1260 void pci_pm_init(struct pci_dev *dev)
1262 int pm;
1263 u16 pmc;
1265 dev->pm_cap = 0;
1267 /* find PCI PM capability in list */
1268 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
1269 if (!pm)
1270 return;
1271 /* Check device's ability to generate PME# */
1272 pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
1274 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
1275 dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
1276 pmc & PCI_PM_CAP_VER_MASK);
1277 return;
1280 dev->pm_cap = pm;
1282 dev->d1_support = false;
1283 dev->d2_support = false;
1284 if (!pci_no_d1d2(dev)) {
1285 if (pmc & PCI_PM_CAP_D1)
1286 dev->d1_support = true;
1287 if (pmc & PCI_PM_CAP_D2)
1288 dev->d2_support = true;
1290 if (dev->d1_support || dev->d2_support)
1291 dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
1292 dev->d1_support ? " D1" : "",
1293 dev->d2_support ? " D2" : "");
1296 pmc &= PCI_PM_CAP_PME_MASK;
1297 if (pmc) {
1298 dev_info(&dev->dev, "PME# supported from%s%s%s%s%s\n",
1299 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
1300 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
1301 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
1302 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
1303 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
1304 dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
1306 * Make device's PM flags reflect the wake-up capability, but
1307 * let the user space enable it to wake up the system as needed.
1309 device_set_wakeup_capable(&dev->dev, true);
1310 device_set_wakeup_enable(&dev->dev, false);
1311 /* Disable the PME# generation functionality */
1312 pci_pme_active(dev, false);
1313 } else {
1314 dev->pme_support = 0;
1319 * platform_pci_wakeup_init - init platform wakeup if present
1320 * @dev: PCI device
1322 * Some devices don't have PCI PM caps but can still generate wakeup
1323 * events through platform methods (like ACPI events). If @dev supports
1324 * platform wakeup events, set the device flag to indicate as much. This
1325 * may be redundant if the device also supports PCI PM caps, but double
1326 * initialization should be safe in that case.
1328 void platform_pci_wakeup_init(struct pci_dev *dev)
1330 if (!platform_pci_can_wakeup(dev))
1331 return;
1333 device_set_wakeup_capable(&dev->dev, true);
1334 device_set_wakeup_enable(&dev->dev, false);
1335 platform_pci_sleep_wake(dev, false);
1339 * pci_add_save_buffer - allocate buffer for saving given capability registers
1340 * @dev: the PCI device
1341 * @cap: the capability to allocate the buffer for
1342 * @size: requested size of the buffer
1344 static int pci_add_cap_save_buffer(
1345 struct pci_dev *dev, char cap, unsigned int size)
1347 int pos;
1348 struct pci_cap_saved_state *save_state;
1350 pos = pci_find_capability(dev, cap);
1351 if (pos <= 0)
1352 return 0;
1354 save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
1355 if (!save_state)
1356 return -ENOMEM;
1358 save_state->cap_nr = cap;
1359 pci_add_saved_cap(dev, save_state);
1361 return 0;
1365 * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
1366 * @dev: the PCI device
1368 void pci_allocate_cap_save_buffers(struct pci_dev *dev)
1370 int error;
1372 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP, 4 * sizeof(u16));
1373 if (error)
1374 dev_err(&dev->dev,
1375 "unable to preallocate PCI Express save buffer\n");
1377 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
1378 if (error)
1379 dev_err(&dev->dev,
1380 "unable to preallocate PCI-X save buffer\n");
1384 * pci_restore_standard_config - restore standard config registers of PCI device
1385 * @dev: PCI device to handle
1387 * This function assumes that the device's configuration space is accessible.
1388 * If the device needs to be powered up, the function will wait for it to
1389 * change the state.
1391 int pci_restore_standard_config(struct pci_dev *dev)
1393 pci_power_t prev_state;
1394 int error;
1396 pci_update_current_state(dev, PCI_D0);
1398 prev_state = dev->current_state;
1399 if (prev_state == PCI_D0)
1400 goto Restore;
1402 error = pci_raw_set_power_state(dev, PCI_D0, false);
1403 if (error)
1404 return error;
1407 * This assumes that we won't get a bus in B2 or B3 from the BIOS, but
1408 * we've made this assumption forever and it appears to be universally
1409 * satisfied.
1411 switch(prev_state) {
1412 case PCI_D3cold:
1413 case PCI_D3hot:
1414 mdelay(pci_pm_d3_delay);
1415 break;
1416 case PCI_D2:
1417 udelay(PCI_PM_D2_DELAY);
1418 break;
1421 pci_update_current_state(dev, PCI_D0);
1423 Restore:
1424 return dev->state_saved ? pci_restore_state(dev) : 0;
1428 * pci_enable_ari - enable ARI forwarding if hardware support it
1429 * @dev: the PCI device
1431 void pci_enable_ari(struct pci_dev *dev)
1433 int pos;
1434 u32 cap;
1435 u16 ctrl;
1436 struct pci_dev *bridge;
1438 if (!dev->is_pcie || dev->devfn)
1439 return;
1441 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1442 if (!pos)
1443 return;
1445 bridge = dev->bus->self;
1446 if (!bridge || !bridge->is_pcie)
1447 return;
1449 pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
1450 if (!pos)
1451 return;
1453 pci_read_config_dword(bridge, pos + PCI_EXP_DEVCAP2, &cap);
1454 if (!(cap & PCI_EXP_DEVCAP2_ARI))
1455 return;
1457 pci_read_config_word(bridge, pos + PCI_EXP_DEVCTL2, &ctrl);
1458 ctrl |= PCI_EXP_DEVCTL2_ARI;
1459 pci_write_config_word(bridge, pos + PCI_EXP_DEVCTL2, ctrl);
1461 bridge->ari_enabled = 1;
1465 * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
1466 * @dev: the PCI device
1467 * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTD, 4=INTD)
1469 * Perform INTx swizzling for a device behind one level of bridge. This is
1470 * required by section 9.1 of the PCI-to-PCI bridge specification for devices
1471 * behind bridges on add-in cards.
1473 u8 pci_swizzle_interrupt_pin(struct pci_dev *dev, u8 pin)
1475 return (((pin - 1) + PCI_SLOT(dev->devfn)) % 4) + 1;
1479 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
1481 u8 pin;
1483 pin = dev->pin;
1484 if (!pin)
1485 return -1;
1487 while (dev->bus->self) {
1488 pin = pci_swizzle_interrupt_pin(dev, pin);
1489 dev = dev->bus->self;
1491 *bridge = dev;
1492 return pin;
1496 * pci_common_swizzle - swizzle INTx all the way to root bridge
1497 * @dev: the PCI device
1498 * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
1500 * Perform INTx swizzling for a device. This traverses through all PCI-to-PCI
1501 * bridges all the way up to a PCI root bus.
1503 u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
1505 u8 pin = *pinp;
1507 while (dev->bus->self) {
1508 pin = pci_swizzle_interrupt_pin(dev, pin);
1509 dev = dev->bus->self;
1511 *pinp = pin;
1512 return PCI_SLOT(dev->devfn);
1516 * pci_release_region - Release a PCI bar
1517 * @pdev: PCI device whose resources were previously reserved by pci_request_region
1518 * @bar: BAR to release
1520 * Releases the PCI I/O and memory resources previously reserved by a
1521 * successful call to pci_request_region. Call this function only
1522 * after all use of the PCI regions has ceased.
1524 void pci_release_region(struct pci_dev *pdev, int bar)
1526 struct pci_devres *dr;
1528 if (pci_resource_len(pdev, bar) == 0)
1529 return;
1530 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1531 release_region(pci_resource_start(pdev, bar),
1532 pci_resource_len(pdev, bar));
1533 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1534 release_mem_region(pci_resource_start(pdev, bar),
1535 pci_resource_len(pdev, bar));
1537 dr = find_pci_dr(pdev);
1538 if (dr)
1539 dr->region_mask &= ~(1 << bar);
1543 * pci_request_region - Reserved PCI I/O and memory resource
1544 * @pdev: PCI device whose resources are to be reserved
1545 * @bar: BAR to be reserved
1546 * @res_name: Name to be associated with resource.
1548 * Mark the PCI region associated with PCI device @pdev BR @bar as
1549 * being reserved by owner @res_name. Do not access any
1550 * address inside the PCI regions unless this call returns
1551 * successfully.
1553 * Returns 0 on success, or %EBUSY on error. A warning
1554 * message is also printed on failure.
1556 static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
1557 int exclusive)
1559 struct pci_devres *dr;
1561 if (pci_resource_len(pdev, bar) == 0)
1562 return 0;
1564 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1565 if (!request_region(pci_resource_start(pdev, bar),
1566 pci_resource_len(pdev, bar), res_name))
1567 goto err_out;
1569 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1570 if (!__request_mem_region(pci_resource_start(pdev, bar),
1571 pci_resource_len(pdev, bar), res_name,
1572 exclusive))
1573 goto err_out;
1576 dr = find_pci_dr(pdev);
1577 if (dr)
1578 dr->region_mask |= 1 << bar;
1580 return 0;
1582 err_out:
1583 dev_warn(&pdev->dev, "BAR %d: can't reserve %s region %pR\n",
1584 bar,
1585 pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
1586 &pdev->resource[bar]);
1587 return -EBUSY;
1591 * pci_request_region - Reserved PCI I/O and memory resource
1592 * @pdev: PCI device whose resources are to be reserved
1593 * @bar: BAR to be reserved
1594 * @res_name: Name to be associated with resource.
1596 * Mark the PCI region associated with PCI device @pdev BR @bar as
1597 * being reserved by owner @res_name. Do not access any
1598 * address inside the PCI regions unless this call returns
1599 * successfully.
1601 * Returns 0 on success, or %EBUSY on error. A warning
1602 * message is also printed on failure.
1604 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1606 return __pci_request_region(pdev, bar, res_name, 0);
1610 * pci_request_region_exclusive - Reserved PCI I/O and memory resource
1611 * @pdev: PCI device whose resources are to be reserved
1612 * @bar: BAR to be reserved
1613 * @res_name: Name to be associated with resource.
1615 * Mark the PCI region associated with PCI device @pdev BR @bar as
1616 * being reserved by owner @res_name. Do not access any
1617 * address inside the PCI regions unless this call returns
1618 * successfully.
1620 * Returns 0 on success, or %EBUSY on error. A warning
1621 * message is also printed on failure.
1623 * The key difference that _exclusive makes it that userspace is
1624 * explicitly not allowed to map the resource via /dev/mem or
1625 * sysfs.
1627 int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name)
1629 return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
1632 * pci_release_selected_regions - Release selected PCI I/O and memory resources
1633 * @pdev: PCI device whose resources were previously reserved
1634 * @bars: Bitmask of BARs to be released
1636 * Release selected PCI I/O and memory resources previously reserved.
1637 * Call this function only after all use of the PCI regions has ceased.
1639 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1641 int i;
1643 for (i = 0; i < 6; i++)
1644 if (bars & (1 << i))
1645 pci_release_region(pdev, i);
1648 int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
1649 const char *res_name, int excl)
1651 int i;
1653 for (i = 0; i < 6; i++)
1654 if (bars & (1 << i))
1655 if (__pci_request_region(pdev, i, res_name, excl))
1656 goto err_out;
1657 return 0;
1659 err_out:
1660 while(--i >= 0)
1661 if (bars & (1 << i))
1662 pci_release_region(pdev, i);
1664 return -EBUSY;
1669 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
1670 * @pdev: PCI device whose resources are to be reserved
1671 * @bars: Bitmask of BARs to be requested
1672 * @res_name: Name to be associated with resource
1674 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
1675 const char *res_name)
1677 return __pci_request_selected_regions(pdev, bars, res_name, 0);
1680 int pci_request_selected_regions_exclusive(struct pci_dev *pdev,
1681 int bars, const char *res_name)
1683 return __pci_request_selected_regions(pdev, bars, res_name,
1684 IORESOURCE_EXCLUSIVE);
1688 * pci_release_regions - Release reserved PCI I/O and memory resources
1689 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
1691 * Releases all PCI I/O and memory resources previously reserved by a
1692 * successful call to pci_request_regions. Call this function only
1693 * after all use of the PCI regions has ceased.
1696 void pci_release_regions(struct pci_dev *pdev)
1698 pci_release_selected_regions(pdev, (1 << 6) - 1);
1702 * pci_request_regions - Reserved PCI I/O and memory resources
1703 * @pdev: PCI device whose resources are to be reserved
1704 * @res_name: Name to be associated with resource.
1706 * Mark all PCI regions associated with PCI device @pdev as
1707 * being reserved by owner @res_name. Do not access any
1708 * address inside the PCI regions unless this call returns
1709 * successfully.
1711 * Returns 0 on success, or %EBUSY on error. A warning
1712 * message is also printed on failure.
1714 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
1716 return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
1720 * pci_request_regions_exclusive - Reserved PCI I/O and memory resources
1721 * @pdev: PCI device whose resources are to be reserved
1722 * @res_name: Name to be associated with resource.
1724 * Mark all PCI regions associated with PCI device @pdev as
1725 * being reserved by owner @res_name. Do not access any
1726 * address inside the PCI regions unless this call returns
1727 * successfully.
1729 * pci_request_regions_exclusive() will mark the region so that
1730 * /dev/mem and the sysfs MMIO access will not be allowed.
1732 * Returns 0 on success, or %EBUSY on error. A warning
1733 * message is also printed on failure.
1735 int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
1737 return pci_request_selected_regions_exclusive(pdev,
1738 ((1 << 6) - 1), res_name);
1741 static void __pci_set_master(struct pci_dev *dev, bool enable)
1743 u16 old_cmd, cmd;
1745 pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
1746 if (enable)
1747 cmd = old_cmd | PCI_COMMAND_MASTER;
1748 else
1749 cmd = old_cmd & ~PCI_COMMAND_MASTER;
1750 if (cmd != old_cmd) {
1751 dev_dbg(&dev->dev, "%s bus mastering\n",
1752 enable ? "enabling" : "disabling");
1753 pci_write_config_word(dev, PCI_COMMAND, cmd);
1755 dev->is_busmaster = enable;
1759 * pci_set_master - enables bus-mastering for device dev
1760 * @dev: the PCI device to enable
1762 * Enables bus-mastering on the device and calls pcibios_set_master()
1763 * to do the needed arch specific settings.
1765 void pci_set_master(struct pci_dev *dev)
1767 __pci_set_master(dev, true);
1768 pcibios_set_master(dev);
1772 * pci_clear_master - disables bus-mastering for device dev
1773 * @dev: the PCI device to disable
1775 void pci_clear_master(struct pci_dev *dev)
1777 __pci_set_master(dev, false);
1780 #ifdef PCI_DISABLE_MWI
1781 int pci_set_mwi(struct pci_dev *dev)
1783 return 0;
1786 int pci_try_set_mwi(struct pci_dev *dev)
1788 return 0;
1791 void pci_clear_mwi(struct pci_dev *dev)
1795 #else
1797 #ifndef PCI_CACHE_LINE_BYTES
1798 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
1799 #endif
1801 /* This can be overridden by arch code. */
1802 /* Don't forget this is measured in 32-bit words, not bytes */
1803 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
1806 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1807 * @dev: the PCI device for which MWI is to be enabled
1809 * Helper function for pci_set_mwi.
1810 * Originally copied from drivers/net/acenic.c.
1811 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1813 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1815 static int
1816 pci_set_cacheline_size(struct pci_dev *dev)
1818 u8 cacheline_size;
1820 if (!pci_cache_line_size)
1821 return -EINVAL; /* The system doesn't support MWI. */
1823 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1824 equal to or multiple of the right value. */
1825 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1826 if (cacheline_size >= pci_cache_line_size &&
1827 (cacheline_size % pci_cache_line_size) == 0)
1828 return 0;
1830 /* Write the correct value. */
1831 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1832 /* Read it back. */
1833 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1834 if (cacheline_size == pci_cache_line_size)
1835 return 0;
1837 dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
1838 "supported\n", pci_cache_line_size << 2);
1840 return -EINVAL;
1844 * pci_set_mwi - enables memory-write-invalidate PCI transaction
1845 * @dev: the PCI device for which MWI is enabled
1847 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1849 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1852 pci_set_mwi(struct pci_dev *dev)
1854 int rc;
1855 u16 cmd;
1857 rc = pci_set_cacheline_size(dev);
1858 if (rc)
1859 return rc;
1861 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1862 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1863 dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
1864 cmd |= PCI_COMMAND_INVALIDATE;
1865 pci_write_config_word(dev, PCI_COMMAND, cmd);
1868 return 0;
1872 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
1873 * @dev: the PCI device for which MWI is enabled
1875 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1876 * Callers are not required to check the return value.
1878 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1880 int pci_try_set_mwi(struct pci_dev *dev)
1882 int rc = pci_set_mwi(dev);
1883 return rc;
1887 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1888 * @dev: the PCI device to disable
1890 * Disables PCI Memory-Write-Invalidate transaction on the device
1892 void
1893 pci_clear_mwi(struct pci_dev *dev)
1895 u16 cmd;
1897 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1898 if (cmd & PCI_COMMAND_INVALIDATE) {
1899 cmd &= ~PCI_COMMAND_INVALIDATE;
1900 pci_write_config_word(dev, PCI_COMMAND, cmd);
1903 #endif /* ! PCI_DISABLE_MWI */
1906 * pci_intx - enables/disables PCI INTx for device dev
1907 * @pdev: the PCI device to operate on
1908 * @enable: boolean: whether to enable or disable PCI INTx
1910 * Enables/disables PCI INTx for device dev
1912 void
1913 pci_intx(struct pci_dev *pdev, int enable)
1915 u16 pci_command, new;
1917 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1919 if (enable) {
1920 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1921 } else {
1922 new = pci_command | PCI_COMMAND_INTX_DISABLE;
1925 if (new != pci_command) {
1926 struct pci_devres *dr;
1928 pci_write_config_word(pdev, PCI_COMMAND, new);
1930 dr = find_pci_dr(pdev);
1931 if (dr && !dr->restore_intx) {
1932 dr->restore_intx = 1;
1933 dr->orig_intx = !enable;
1939 * pci_msi_off - disables any msi or msix capabilities
1940 * @dev: the PCI device to operate on
1942 * If you want to use msi see pci_enable_msi and friends.
1943 * This is a lower level primitive that allows us to disable
1944 * msi operation at the device level.
1946 void pci_msi_off(struct pci_dev *dev)
1948 int pos;
1949 u16 control;
1951 pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
1952 if (pos) {
1953 pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
1954 control &= ~PCI_MSI_FLAGS_ENABLE;
1955 pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
1957 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1958 if (pos) {
1959 pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
1960 control &= ~PCI_MSIX_FLAGS_ENABLE;
1961 pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
1965 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
1967 * These can be overridden by arch-specific implementations
1970 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
1972 if (!pci_dma_supported(dev, mask))
1973 return -EIO;
1975 dev->dma_mask = mask;
1977 return 0;
1981 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
1983 if (!pci_dma_supported(dev, mask))
1984 return -EIO;
1986 dev->dev.coherent_dma_mask = mask;
1988 return 0;
1990 #endif
1992 #ifndef HAVE_ARCH_PCI_SET_DMA_MAX_SEGMENT_SIZE
1993 int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
1995 return dma_set_max_seg_size(&dev->dev, size);
1997 EXPORT_SYMBOL(pci_set_dma_max_seg_size);
1998 #endif
2000 #ifndef HAVE_ARCH_PCI_SET_DMA_SEGMENT_BOUNDARY
2001 int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
2003 return dma_set_seg_boundary(&dev->dev, mask);
2005 EXPORT_SYMBOL(pci_set_dma_seg_boundary);
2006 #endif
2008 static int __pcie_flr(struct pci_dev *dev, int probe)
2010 u16 status;
2011 u32 cap;
2012 int exppos = pci_find_capability(dev, PCI_CAP_ID_EXP);
2014 if (!exppos)
2015 return -ENOTTY;
2016 pci_read_config_dword(dev, exppos + PCI_EXP_DEVCAP, &cap);
2017 if (!(cap & PCI_EXP_DEVCAP_FLR))
2018 return -ENOTTY;
2020 if (probe)
2021 return 0;
2023 pci_block_user_cfg_access(dev);
2025 /* Wait for Transaction Pending bit clean */
2026 msleep(100);
2027 pci_read_config_word(dev, exppos + PCI_EXP_DEVSTA, &status);
2028 if (status & PCI_EXP_DEVSTA_TRPND) {
2029 dev_info(&dev->dev, "Busy after 100ms while trying to reset; "
2030 "sleeping for 1 second\n");
2031 ssleep(1);
2032 pci_read_config_word(dev, exppos + PCI_EXP_DEVSTA, &status);
2033 if (status & PCI_EXP_DEVSTA_TRPND)
2034 dev_info(&dev->dev, "Still busy after 1s; "
2035 "proceeding with reset anyway\n");
2038 pci_write_config_word(dev, exppos + PCI_EXP_DEVCTL,
2039 PCI_EXP_DEVCTL_BCR_FLR);
2040 mdelay(100);
2042 pci_unblock_user_cfg_access(dev);
2043 return 0;
2046 static int __pci_af_flr(struct pci_dev *dev, int probe)
2048 int cappos = pci_find_capability(dev, PCI_CAP_ID_AF);
2049 u8 status;
2050 u8 cap;
2052 if (!cappos)
2053 return -ENOTTY;
2054 pci_read_config_byte(dev, cappos + PCI_AF_CAP, &cap);
2055 if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
2056 return -ENOTTY;
2058 if (probe)
2059 return 0;
2061 pci_block_user_cfg_access(dev);
2063 /* Wait for Transaction Pending bit clean */
2064 msleep(100);
2065 pci_read_config_byte(dev, cappos + PCI_AF_STATUS, &status);
2066 if (status & PCI_AF_STATUS_TP) {
2067 dev_info(&dev->dev, "Busy after 100ms while trying to"
2068 " reset; sleeping for 1 second\n");
2069 ssleep(1);
2070 pci_read_config_byte(dev,
2071 cappos + PCI_AF_STATUS, &status);
2072 if (status & PCI_AF_STATUS_TP)
2073 dev_info(&dev->dev, "Still busy after 1s; "
2074 "proceeding with reset anyway\n");
2076 pci_write_config_byte(dev, cappos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
2077 mdelay(100);
2079 pci_unblock_user_cfg_access(dev);
2080 return 0;
2083 static int __pci_reset_function(struct pci_dev *pdev, int probe)
2085 int res;
2087 res = __pcie_flr(pdev, probe);
2088 if (res != -ENOTTY)
2089 return res;
2091 res = __pci_af_flr(pdev, probe);
2092 if (res != -ENOTTY)
2093 return res;
2095 return res;
2099 * pci_execute_reset_function() - Reset a PCI device function
2100 * @dev: Device function to reset
2102 * Some devices allow an individual function to be reset without affecting
2103 * other functions in the same device. The PCI device must be responsive
2104 * to PCI config space in order to use this function.
2106 * The device function is presumed to be unused when this function is called.
2107 * Resetting the device will make the contents of PCI configuration space
2108 * random, so any caller of this must be prepared to reinitialise the
2109 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
2110 * etc.
2112 * Returns 0 if the device function was successfully reset or -ENOTTY if the
2113 * device doesn't support resetting a single function.
2115 int pci_execute_reset_function(struct pci_dev *dev)
2117 return __pci_reset_function(dev, 0);
2119 EXPORT_SYMBOL_GPL(pci_execute_reset_function);
2122 * pci_reset_function() - quiesce and reset a PCI device function
2123 * @dev: Device function to reset
2125 * Some devices allow an individual function to be reset without affecting
2126 * other functions in the same device. The PCI device must be responsive
2127 * to PCI config space in order to use this function.
2129 * This function does not just reset the PCI portion of a device, but
2130 * clears all the state associated with the device. This function differs
2131 * from pci_execute_reset_function in that it saves and restores device state
2132 * over the reset.
2134 * Returns 0 if the device function was successfully reset or -ENOTTY if the
2135 * device doesn't support resetting a single function.
2137 int pci_reset_function(struct pci_dev *dev)
2139 int r = __pci_reset_function(dev, 1);
2141 if (r < 0)
2142 return r;
2144 if (!dev->msi_enabled && !dev->msix_enabled && dev->irq != 0)
2145 disable_irq(dev->irq);
2146 pci_save_state(dev);
2148 pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
2150 r = pci_execute_reset_function(dev);
2152 pci_restore_state(dev);
2153 if (!dev->msi_enabled && !dev->msix_enabled && dev->irq != 0)
2154 enable_irq(dev->irq);
2156 return r;
2158 EXPORT_SYMBOL_GPL(pci_reset_function);
2161 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
2162 * @dev: PCI device to query
2164 * Returns mmrbc: maximum designed memory read count in bytes
2165 * or appropriate error value.
2167 int pcix_get_max_mmrbc(struct pci_dev *dev)
2169 int err, cap;
2170 u32 stat;
2172 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2173 if (!cap)
2174 return -EINVAL;
2176 err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
2177 if (err)
2178 return -EINVAL;
2180 return (stat & PCI_X_STATUS_MAX_READ) >> 12;
2182 EXPORT_SYMBOL(pcix_get_max_mmrbc);
2185 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
2186 * @dev: PCI device to query
2188 * Returns mmrbc: maximum memory read count in bytes
2189 * or appropriate error value.
2191 int pcix_get_mmrbc(struct pci_dev *dev)
2193 int ret, cap;
2194 u32 cmd;
2196 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2197 if (!cap)
2198 return -EINVAL;
2200 ret = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
2201 if (!ret)
2202 ret = 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
2204 return ret;
2206 EXPORT_SYMBOL(pcix_get_mmrbc);
2209 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
2210 * @dev: PCI device to query
2211 * @mmrbc: maximum memory read count in bytes
2212 * valid values are 512, 1024, 2048, 4096
2214 * If possible sets maximum memory read byte count, some bridges have erratas
2215 * that prevent this.
2217 int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
2219 int cap, err = -EINVAL;
2220 u32 stat, cmd, v, o;
2222 if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
2223 goto out;
2225 v = ffs(mmrbc) - 10;
2227 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2228 if (!cap)
2229 goto out;
2231 err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
2232 if (err)
2233 goto out;
2235 if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
2236 return -E2BIG;
2238 err = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
2239 if (err)
2240 goto out;
2242 o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
2243 if (o != v) {
2244 if (v > o && dev->bus &&
2245 (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
2246 return -EIO;
2248 cmd &= ~PCI_X_CMD_MAX_READ;
2249 cmd |= v << 2;
2250 err = pci_write_config_dword(dev, cap + PCI_X_CMD, cmd);
2252 out:
2253 return err;
2255 EXPORT_SYMBOL(pcix_set_mmrbc);
2258 * pcie_get_readrq - get PCI Express read request size
2259 * @dev: PCI device to query
2261 * Returns maximum memory read request in bytes
2262 * or appropriate error value.
2264 int pcie_get_readrq(struct pci_dev *dev)
2266 int ret, cap;
2267 u16 ctl;
2269 cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
2270 if (!cap)
2271 return -EINVAL;
2273 ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
2274 if (!ret)
2275 ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
2277 return ret;
2279 EXPORT_SYMBOL(pcie_get_readrq);
2282 * pcie_set_readrq - set PCI Express maximum memory read request
2283 * @dev: PCI device to query
2284 * @rq: maximum memory read count in bytes
2285 * valid values are 128, 256, 512, 1024, 2048, 4096
2287 * If possible sets maximum read byte count
2289 int pcie_set_readrq(struct pci_dev *dev, int rq)
2291 int cap, err = -EINVAL;
2292 u16 ctl, v;
2294 if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
2295 goto out;
2297 v = (ffs(rq) - 8) << 12;
2299 cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
2300 if (!cap)
2301 goto out;
2303 err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
2304 if (err)
2305 goto out;
2307 if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
2308 ctl &= ~PCI_EXP_DEVCTL_READRQ;
2309 ctl |= v;
2310 err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
2313 out:
2314 return err;
2316 EXPORT_SYMBOL(pcie_set_readrq);
2319 * pci_select_bars - Make BAR mask from the type of resource
2320 * @dev: the PCI device for which BAR mask is made
2321 * @flags: resource type mask to be selected
2323 * This helper routine makes bar mask from the type of resource.
2325 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
2327 int i, bars = 0;
2328 for (i = 0; i < PCI_NUM_RESOURCES; i++)
2329 if (pci_resource_flags(dev, i) & flags)
2330 bars |= (1 << i);
2331 return bars;
2335 * pci_resource_bar - get position of the BAR associated with a resource
2336 * @dev: the PCI device
2337 * @resno: the resource number
2338 * @type: the BAR type to be filled in
2340 * Returns BAR position in config space, or 0 if the BAR is invalid.
2342 int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type)
2344 if (resno < PCI_ROM_RESOURCE) {
2345 *type = pci_bar_unknown;
2346 return PCI_BASE_ADDRESS_0 + 4 * resno;
2347 } else if (resno == PCI_ROM_RESOURCE) {
2348 *type = pci_bar_mem32;
2349 return dev->rom_base_reg;
2352 dev_err(&dev->dev, "BAR: invalid resource #%d\n", resno);
2353 return 0;
2356 static void __devinit pci_no_domains(void)
2358 #ifdef CONFIG_PCI_DOMAINS
2359 pci_domains_supported = 0;
2360 #endif
2364 * pci_ext_cfg_enabled - can we access extended PCI config space?
2365 * @dev: The PCI device of the root bridge.
2367 * Returns 1 if we can access PCI extended config space (offsets
2368 * greater than 0xff). This is the default implementation. Architecture
2369 * implementations can override this.
2371 int __attribute__ ((weak)) pci_ext_cfg_avail(struct pci_dev *dev)
2373 return 1;
2376 static int __devinit pci_init(void)
2378 struct pci_dev *dev = NULL;
2380 while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
2381 pci_fixup_device(pci_fixup_final, dev);
2384 return 0;
2387 static int __init pci_setup(char *str)
2389 while (str) {
2390 char *k = strchr(str, ',');
2391 if (k)
2392 *k++ = 0;
2393 if (*str && (str = pcibios_setup(str)) && *str) {
2394 if (!strcmp(str, "nomsi")) {
2395 pci_no_msi();
2396 } else if (!strcmp(str, "noaer")) {
2397 pci_no_aer();
2398 } else if (!strcmp(str, "nodomains")) {
2399 pci_no_domains();
2400 } else if (!strncmp(str, "cbiosize=", 9)) {
2401 pci_cardbus_io_size = memparse(str + 9, &str);
2402 } else if (!strncmp(str, "cbmemsize=", 10)) {
2403 pci_cardbus_mem_size = memparse(str + 10, &str);
2404 } else {
2405 printk(KERN_ERR "PCI: Unknown option `%s'\n",
2406 str);
2409 str = k;
2411 return 0;
2413 early_param("pci", pci_setup);
2415 device_initcall(pci_init);
2417 EXPORT_SYMBOL(pci_reenable_device);
2418 EXPORT_SYMBOL(pci_enable_device_io);
2419 EXPORT_SYMBOL(pci_enable_device_mem);
2420 EXPORT_SYMBOL(pci_enable_device);
2421 EXPORT_SYMBOL(pcim_enable_device);
2422 EXPORT_SYMBOL(pcim_pin_device);
2423 EXPORT_SYMBOL(pci_disable_device);
2424 EXPORT_SYMBOL(pci_find_capability);
2425 EXPORT_SYMBOL(pci_bus_find_capability);
2426 EXPORT_SYMBOL(pci_release_regions);
2427 EXPORT_SYMBOL(pci_request_regions);
2428 EXPORT_SYMBOL(pci_request_regions_exclusive);
2429 EXPORT_SYMBOL(pci_release_region);
2430 EXPORT_SYMBOL(pci_request_region);
2431 EXPORT_SYMBOL(pci_request_region_exclusive);
2432 EXPORT_SYMBOL(pci_release_selected_regions);
2433 EXPORT_SYMBOL(pci_request_selected_regions);
2434 EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
2435 EXPORT_SYMBOL(pci_set_master);
2436 EXPORT_SYMBOL(pci_clear_master);
2437 EXPORT_SYMBOL(pci_set_mwi);
2438 EXPORT_SYMBOL(pci_try_set_mwi);
2439 EXPORT_SYMBOL(pci_clear_mwi);
2440 EXPORT_SYMBOL_GPL(pci_intx);
2441 EXPORT_SYMBOL(pci_set_dma_mask);
2442 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
2443 EXPORT_SYMBOL(pci_assign_resource);
2444 EXPORT_SYMBOL(pci_find_parent_resource);
2445 EXPORT_SYMBOL(pci_select_bars);
2447 EXPORT_SYMBOL(pci_set_power_state);
2448 EXPORT_SYMBOL(pci_save_state);
2449 EXPORT_SYMBOL(pci_restore_state);
2450 EXPORT_SYMBOL(pci_pme_capable);
2451 EXPORT_SYMBOL(pci_pme_active);
2452 EXPORT_SYMBOL(pci_enable_wake);
2453 EXPORT_SYMBOL(pci_wake_from_d3);
2454 EXPORT_SYMBOL(pci_target_state);
2455 EXPORT_SYMBOL(pci_prepare_to_sleep);
2456 EXPORT_SYMBOL(pci_back_from_sleep);
2457 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);