fat: i_blocks warning fix
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / pci / pci.c
blob21f2ac639cab2f31937971113fe9872275cfd9a0
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 = 10;
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 #if 0
60 /**
61 * pci_max_busnr - returns maximum PCI bus number
63 * Returns the highest PCI bus number present in the system global list of
64 * PCI buses.
66 unsigned char __devinit
67 pci_max_busnr(void)
69 struct pci_bus *bus = NULL;
70 unsigned char max, n;
72 max = 0;
73 while ((bus = pci_find_next_bus(bus)) != NULL) {
74 n = pci_bus_max_busnr(bus);
75 if(n > max)
76 max = n;
78 return max;
81 #endif /* 0 */
83 #define PCI_FIND_CAP_TTL 48
85 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
86 u8 pos, int cap, int *ttl)
88 u8 id;
90 while ((*ttl)--) {
91 pci_bus_read_config_byte(bus, devfn, pos, &pos);
92 if (pos < 0x40)
93 break;
94 pos &= ~3;
95 pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
96 &id);
97 if (id == 0xff)
98 break;
99 if (id == cap)
100 return pos;
101 pos += PCI_CAP_LIST_NEXT;
103 return 0;
106 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
107 u8 pos, int cap)
109 int ttl = PCI_FIND_CAP_TTL;
111 return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
114 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
116 return __pci_find_next_cap(dev->bus, dev->devfn,
117 pos + PCI_CAP_LIST_NEXT, cap);
119 EXPORT_SYMBOL_GPL(pci_find_next_capability);
121 static int __pci_bus_find_cap_start(struct pci_bus *bus,
122 unsigned int devfn, u8 hdr_type)
124 u16 status;
126 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
127 if (!(status & PCI_STATUS_CAP_LIST))
128 return 0;
130 switch (hdr_type) {
131 case PCI_HEADER_TYPE_NORMAL:
132 case PCI_HEADER_TYPE_BRIDGE:
133 return PCI_CAPABILITY_LIST;
134 case PCI_HEADER_TYPE_CARDBUS:
135 return PCI_CB_CAPABILITY_LIST;
136 default:
137 return 0;
140 return 0;
144 * pci_find_capability - query for devices' capabilities
145 * @dev: PCI device to query
146 * @cap: capability code
148 * Tell if a device supports a given PCI capability.
149 * Returns the address of the requested capability structure within the
150 * device's PCI configuration space or 0 in case the device does not
151 * support it. Possible values for @cap:
153 * %PCI_CAP_ID_PM Power Management
154 * %PCI_CAP_ID_AGP Accelerated Graphics Port
155 * %PCI_CAP_ID_VPD Vital Product Data
156 * %PCI_CAP_ID_SLOTID Slot Identification
157 * %PCI_CAP_ID_MSI Message Signalled Interrupts
158 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
159 * %PCI_CAP_ID_PCIX PCI-X
160 * %PCI_CAP_ID_EXP PCI Express
162 int pci_find_capability(struct pci_dev *dev, int cap)
164 int pos;
166 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
167 if (pos)
168 pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
170 return pos;
174 * pci_bus_find_capability - query for devices' capabilities
175 * @bus: the PCI bus to query
176 * @devfn: PCI device to query
177 * @cap: capability code
179 * Like pci_find_capability() but works for pci devices that do not have a
180 * pci_dev structure set up yet.
182 * Returns the address of the requested capability structure within the
183 * device's PCI configuration space or 0 in case the device does not
184 * support it.
186 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
188 int pos;
189 u8 hdr_type;
191 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
193 pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
194 if (pos)
195 pos = __pci_find_next_cap(bus, devfn, pos, cap);
197 return pos;
201 * pci_find_ext_capability - Find an extended capability
202 * @dev: PCI device to query
203 * @cap: capability code
205 * Returns the address of the requested extended capability structure
206 * within the device's PCI configuration space or 0 if the device does
207 * not support it. Possible values for @cap:
209 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
210 * %PCI_EXT_CAP_ID_VC Virtual Channel
211 * %PCI_EXT_CAP_ID_DSN Device Serial Number
212 * %PCI_EXT_CAP_ID_PWR Power Budgeting
214 int pci_find_ext_capability(struct pci_dev *dev, int cap)
216 u32 header;
217 int ttl;
218 int pos = PCI_CFG_SPACE_SIZE;
220 /* minimum 8 bytes per capability */
221 ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
223 if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
224 return 0;
226 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
227 return 0;
230 * If we have no capabilities, this is indicated by cap ID,
231 * cap version and next pointer all being 0.
233 if (header == 0)
234 return 0;
236 while (ttl-- > 0) {
237 if (PCI_EXT_CAP_ID(header) == cap)
238 return pos;
240 pos = PCI_EXT_CAP_NEXT(header);
241 if (pos < PCI_CFG_SPACE_SIZE)
242 break;
244 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
245 break;
248 return 0;
250 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
252 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
254 int rc, ttl = PCI_FIND_CAP_TTL;
255 u8 cap, mask;
257 if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
258 mask = HT_3BIT_CAP_MASK;
259 else
260 mask = HT_5BIT_CAP_MASK;
262 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
263 PCI_CAP_ID_HT, &ttl);
264 while (pos) {
265 rc = pci_read_config_byte(dev, pos + 3, &cap);
266 if (rc != PCIBIOS_SUCCESSFUL)
267 return 0;
269 if ((cap & mask) == ht_cap)
270 return pos;
272 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
273 pos + PCI_CAP_LIST_NEXT,
274 PCI_CAP_ID_HT, &ttl);
277 return 0;
280 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
281 * @dev: PCI device to query
282 * @pos: Position from which to continue searching
283 * @ht_cap: Hypertransport capability code
285 * To be used in conjunction with pci_find_ht_capability() to search for
286 * all capabilities matching @ht_cap. @pos should always be a value returned
287 * from pci_find_ht_capability().
289 * NB. To be 100% safe against broken PCI devices, the caller should take
290 * steps to avoid an infinite loop.
292 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
294 return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
296 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
299 * pci_find_ht_capability - query a device's Hypertransport capabilities
300 * @dev: PCI device to query
301 * @ht_cap: Hypertransport capability code
303 * Tell if a device supports a given Hypertransport capability.
304 * Returns an address within the device's PCI configuration space
305 * or 0 in case the device does not support the request capability.
306 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
307 * which has a Hypertransport capability matching @ht_cap.
309 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
311 int pos;
313 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
314 if (pos)
315 pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
317 return pos;
319 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
322 * pci_find_parent_resource - return resource region of parent bus of given region
323 * @dev: PCI device structure contains resources to be searched
324 * @res: child resource record for which parent is sought
326 * For given resource region of given device, return the resource
327 * region of parent bus the given region is contained in or where
328 * it should be allocated from.
330 struct resource *
331 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
333 const struct pci_bus *bus = dev->bus;
334 int i;
335 struct resource *best = NULL;
337 for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
338 struct resource *r = bus->resource[i];
339 if (!r)
340 continue;
341 if (res->start && !(res->start >= r->start && res->end <= r->end))
342 continue; /* Not contained */
343 if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
344 continue; /* Wrong type */
345 if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
346 return r; /* Exact match */
347 if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
348 best = r; /* Approximating prefetchable by non-prefetchable */
350 return best;
354 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
355 * @dev: PCI device to have its BARs restored
357 * Restore the BAR values for a given device, so as to make it
358 * accessible by its driver.
360 static void
361 pci_restore_bars(struct pci_dev *dev)
363 int i, numres;
365 switch (dev->hdr_type) {
366 case PCI_HEADER_TYPE_NORMAL:
367 numres = 6;
368 break;
369 case PCI_HEADER_TYPE_BRIDGE:
370 numres = 2;
371 break;
372 case PCI_HEADER_TYPE_CARDBUS:
373 numres = 1;
374 break;
375 default:
376 /* Should never get here, but just in case... */
377 return;
380 for (i = 0; i < numres; i ++)
381 pci_update_resource(dev, &dev->resource[i], i);
384 static struct pci_platform_pm_ops *pci_platform_pm;
386 int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
388 if (!ops->is_manageable || !ops->set_state || !ops->choose_state
389 || !ops->sleep_wake || !ops->can_wakeup)
390 return -EINVAL;
391 pci_platform_pm = ops;
392 return 0;
395 static inline bool platform_pci_power_manageable(struct pci_dev *dev)
397 return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
400 static inline int platform_pci_set_power_state(struct pci_dev *dev,
401 pci_power_t t)
403 return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
406 static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
408 return pci_platform_pm ?
409 pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
412 static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
414 return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
417 static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
419 return pci_platform_pm ?
420 pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
424 * pci_raw_set_power_state - Use PCI PM registers to set the power state of
425 * given PCI device
426 * @dev: PCI device to handle.
427 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
429 * RETURN VALUE:
430 * -EINVAL if the requested state is invalid.
431 * -EIO if device does not support PCI PM or its PM capabilities register has a
432 * wrong version, or device doesn't support the requested state.
433 * 0 if device already is in the requested state.
434 * 0 if device's power state has been successfully changed.
436 static int
437 pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
439 u16 pmcsr;
440 bool need_restore = false;
442 if (!dev->pm_cap)
443 return -EIO;
445 if (state < PCI_D0 || state > PCI_D3hot)
446 return -EINVAL;
448 /* Validate current state:
449 * Can enter D0 from any state, but if we can only go deeper
450 * to sleep if we're already in a low power state
452 if (dev->current_state == state) {
453 /* we're already there */
454 return 0;
455 } else if (state != PCI_D0 && dev->current_state <= PCI_D3cold
456 && dev->current_state > state) {
457 dev_err(&dev->dev, "invalid power transition "
458 "(from state %d to %d)\n", dev->current_state, state);
459 return -EINVAL;
462 /* check if this device supports the desired state */
463 if ((state == PCI_D1 && !dev->d1_support)
464 || (state == PCI_D2 && !dev->d2_support))
465 return -EIO;
467 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
469 /* If we're (effectively) in D3, force entire word to 0.
470 * This doesn't affect PME_Status, disables PME_En, and
471 * sets PowerState to 0.
473 switch (dev->current_state) {
474 case PCI_D0:
475 case PCI_D1:
476 case PCI_D2:
477 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
478 pmcsr |= state;
479 break;
480 case PCI_UNKNOWN: /* Boot-up */
481 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
482 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
483 need_restore = true;
484 /* Fall-through: force to D0 */
485 default:
486 pmcsr = 0;
487 break;
490 /* enter specified state */
491 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
493 /* Mandatory power management transition delays */
494 /* see PCI PM 1.1 5.6.1 table 18 */
495 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
496 msleep(pci_pm_d3_delay);
497 else if (state == PCI_D2 || dev->current_state == PCI_D2)
498 udelay(200);
500 dev->current_state = state;
502 /* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
503 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
504 * from D3hot to D0 _may_ perform an internal reset, thereby
505 * going to "D0 Uninitialized" rather than "D0 Initialized".
506 * For example, at least some versions of the 3c905B and the
507 * 3c556B exhibit this behaviour.
509 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
510 * devices in a D3hot state at boot. Consequently, we need to
511 * restore at least the BARs so that the device will be
512 * accessible to its driver.
514 if (need_restore)
515 pci_restore_bars(dev);
517 if (dev->bus->self)
518 pcie_aspm_pm_state_change(dev->bus->self);
520 return 0;
524 * pci_update_current_state - Read PCI power state of given device from its
525 * PCI PM registers and cache it
526 * @dev: PCI device to handle.
528 static void pci_update_current_state(struct pci_dev *dev)
530 if (dev->pm_cap) {
531 u16 pmcsr;
533 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
534 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
539 * pci_set_power_state - Set the power state of a PCI device
540 * @dev: PCI device to handle.
541 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
543 * Transition a device to a new power state, using the platform formware and/or
544 * the device's PCI PM registers.
546 * RETURN VALUE:
547 * -EINVAL if the requested state is invalid.
548 * -EIO if device does not support PCI PM or its PM capabilities register has a
549 * wrong version, or device doesn't support the requested state.
550 * 0 if device already is in the requested state.
551 * 0 if device's power state has been successfully changed.
553 int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
555 int error;
557 /* bound the state we're entering */
558 if (state > PCI_D3hot)
559 state = PCI_D3hot;
560 else if (state < PCI_D0)
561 state = PCI_D0;
562 else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
564 * If the device or the parent bridge do not support PCI PM,
565 * ignore the request if we're doing anything other than putting
566 * it into D0 (which would only happen on boot).
568 return 0;
570 if (state == PCI_D0 && platform_pci_power_manageable(dev)) {
572 * Allow the platform to change the state, for example via ACPI
573 * _PR0, _PS0 and some such, but do not trust it.
575 int ret = platform_pci_set_power_state(dev, PCI_D0);
576 if (!ret)
577 pci_update_current_state(dev);
579 /* This device is quirked not to be put into D3, so
580 don't put it in D3 */
581 if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
582 return 0;
584 error = pci_raw_set_power_state(dev, state);
586 if (state > PCI_D0 && platform_pci_power_manageable(dev)) {
587 /* Allow the platform to finalize the transition */
588 int ret = platform_pci_set_power_state(dev, state);
589 if (!ret) {
590 pci_update_current_state(dev);
591 error = 0;
595 return error;
599 * pci_choose_state - Choose the power state of a PCI device
600 * @dev: PCI device to be suspended
601 * @state: target sleep state for the whole system. This is the value
602 * that is passed to suspend() function.
604 * Returns PCI power state suitable for given device and given system
605 * message.
608 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
610 pci_power_t ret;
612 if (!pci_find_capability(dev, PCI_CAP_ID_PM))
613 return PCI_D0;
615 ret = platform_pci_choose_state(dev);
616 if (ret != PCI_POWER_ERROR)
617 return ret;
619 switch (state.event) {
620 case PM_EVENT_ON:
621 return PCI_D0;
622 case PM_EVENT_FREEZE:
623 case PM_EVENT_PRETHAW:
624 /* REVISIT both freeze and pre-thaw "should" use D0 */
625 case PM_EVENT_SUSPEND:
626 case PM_EVENT_HIBERNATE:
627 return PCI_D3hot;
628 default:
629 dev_info(&dev->dev, "unrecognized suspend event %d\n",
630 state.event);
631 BUG();
633 return PCI_D0;
636 EXPORT_SYMBOL(pci_choose_state);
638 static int pci_save_pcie_state(struct pci_dev *dev)
640 int pos, i = 0;
641 struct pci_cap_saved_state *save_state;
642 u16 *cap;
643 int found = 0;
645 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
646 if (pos <= 0)
647 return 0;
649 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
650 if (!save_state)
651 save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);
652 else
653 found = 1;
654 if (!save_state) {
655 dev_err(&dev->dev, "out of memory in pci_save_pcie_state\n");
656 return -ENOMEM;
658 cap = (u16 *)&save_state->data[0];
660 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
661 pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
662 pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
663 pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
664 save_state->cap_nr = PCI_CAP_ID_EXP;
665 if (!found)
666 pci_add_saved_cap(dev, save_state);
667 return 0;
670 static void pci_restore_pcie_state(struct pci_dev *dev)
672 int i = 0, pos;
673 struct pci_cap_saved_state *save_state;
674 u16 *cap;
676 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
677 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
678 if (!save_state || pos <= 0)
679 return;
680 cap = (u16 *)&save_state->data[0];
682 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
683 pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
684 pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
685 pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
689 static int pci_save_pcix_state(struct pci_dev *dev)
691 int pos, i = 0;
692 struct pci_cap_saved_state *save_state;
693 u16 *cap;
694 int found = 0;
696 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
697 if (pos <= 0)
698 return 0;
700 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
701 if (!save_state)
702 save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);
703 else
704 found = 1;
705 if (!save_state) {
706 dev_err(&dev->dev, "out of memory in pci_save_pcie_state\n");
707 return -ENOMEM;
709 cap = (u16 *)&save_state->data[0];
711 pci_read_config_word(dev, pos + PCI_X_CMD, &cap[i++]);
712 save_state->cap_nr = PCI_CAP_ID_PCIX;
713 if (!found)
714 pci_add_saved_cap(dev, save_state);
715 return 0;
718 static void pci_restore_pcix_state(struct pci_dev *dev)
720 int i = 0, pos;
721 struct pci_cap_saved_state *save_state;
722 u16 *cap;
724 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
725 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
726 if (!save_state || pos <= 0)
727 return;
728 cap = (u16 *)&save_state->data[0];
730 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
735 * pci_save_state - save the PCI configuration space of a device before suspending
736 * @dev: - PCI device that we're dealing with
739 pci_save_state(struct pci_dev *dev)
741 int i;
742 /* XXX: 100% dword access ok here? */
743 for (i = 0; i < 16; i++)
744 pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
745 if ((i = pci_save_pcie_state(dev)) != 0)
746 return i;
747 if ((i = pci_save_pcix_state(dev)) != 0)
748 return i;
749 return 0;
752 /**
753 * pci_restore_state - Restore the saved state of a PCI device
754 * @dev: - PCI device that we're dealing with
756 int
757 pci_restore_state(struct pci_dev *dev)
759 int i;
760 u32 val;
762 /* PCI Express register must be restored first */
763 pci_restore_pcie_state(dev);
766 * The Base Address register should be programmed before the command
767 * register(s)
769 for (i = 15; i >= 0; i--) {
770 pci_read_config_dword(dev, i * 4, &val);
771 if (val != dev->saved_config_space[i]) {
772 dev_printk(KERN_DEBUG, &dev->dev, "restoring config "
773 "space at offset %#x (was %#x, writing %#x)\n",
774 i, val, (int)dev->saved_config_space[i]);
775 pci_write_config_dword(dev,i * 4,
776 dev->saved_config_space[i]);
779 pci_restore_pcix_state(dev);
780 pci_restore_msi_state(dev);
782 return 0;
785 static int do_pci_enable_device(struct pci_dev *dev, int bars)
787 int err;
789 err = pci_set_power_state(dev, PCI_D0);
790 if (err < 0 && err != -EIO)
791 return err;
792 err = pcibios_enable_device(dev, bars);
793 if (err < 0)
794 return err;
795 pci_fixup_device(pci_fixup_enable, dev);
797 return 0;
801 * pci_reenable_device - Resume abandoned device
802 * @dev: PCI device to be resumed
804 * Note this function is a backend of pci_default_resume and is not supposed
805 * to be called by normal code, write proper resume handler and use it instead.
807 int pci_reenable_device(struct pci_dev *dev)
809 if (atomic_read(&dev->enable_cnt))
810 return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
811 return 0;
814 static int __pci_enable_device_flags(struct pci_dev *dev,
815 resource_size_t flags)
817 int err;
818 int i, bars = 0;
820 if (atomic_add_return(1, &dev->enable_cnt) > 1)
821 return 0; /* already enabled */
823 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
824 if (dev->resource[i].flags & flags)
825 bars |= (1 << i);
827 err = do_pci_enable_device(dev, bars);
828 if (err < 0)
829 atomic_dec(&dev->enable_cnt);
830 return err;
834 * pci_enable_device_io - Initialize a device for use with IO space
835 * @dev: PCI device to be initialized
837 * Initialize device before it's used by a driver. Ask low-level code
838 * to enable I/O resources. Wake up the device if it was suspended.
839 * Beware, this function can fail.
841 int pci_enable_device_io(struct pci_dev *dev)
843 return __pci_enable_device_flags(dev, IORESOURCE_IO);
847 * pci_enable_device_mem - Initialize a device for use with Memory space
848 * @dev: PCI device to be initialized
850 * Initialize device before it's used by a driver. Ask low-level code
851 * to enable Memory resources. Wake up the device if it was suspended.
852 * Beware, this function can fail.
854 int pci_enable_device_mem(struct pci_dev *dev)
856 return __pci_enable_device_flags(dev, IORESOURCE_MEM);
860 * pci_enable_device - Initialize device before it's used by a driver.
861 * @dev: PCI device to be initialized
863 * Initialize device before it's used by a driver. Ask low-level code
864 * to enable I/O and memory. Wake up the device if it was suspended.
865 * Beware, this function can fail.
867 * Note we don't actually enable the device many times if we call
868 * this function repeatedly (we just increment the count).
870 int pci_enable_device(struct pci_dev *dev)
872 return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
876 * Managed PCI resources. This manages device on/off, intx/msi/msix
877 * on/off and BAR regions. pci_dev itself records msi/msix status, so
878 * there's no need to track it separately. pci_devres is initialized
879 * when a device is enabled using managed PCI device enable interface.
881 struct pci_devres {
882 unsigned int enabled:1;
883 unsigned int pinned:1;
884 unsigned int orig_intx:1;
885 unsigned int restore_intx:1;
886 u32 region_mask;
889 static void pcim_release(struct device *gendev, void *res)
891 struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
892 struct pci_devres *this = res;
893 int i;
895 if (dev->msi_enabled)
896 pci_disable_msi(dev);
897 if (dev->msix_enabled)
898 pci_disable_msix(dev);
900 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
901 if (this->region_mask & (1 << i))
902 pci_release_region(dev, i);
904 if (this->restore_intx)
905 pci_intx(dev, this->orig_intx);
907 if (this->enabled && !this->pinned)
908 pci_disable_device(dev);
911 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
913 struct pci_devres *dr, *new_dr;
915 dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
916 if (dr)
917 return dr;
919 new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
920 if (!new_dr)
921 return NULL;
922 return devres_get(&pdev->dev, new_dr, NULL, NULL);
925 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
927 if (pci_is_managed(pdev))
928 return devres_find(&pdev->dev, pcim_release, NULL, NULL);
929 return NULL;
933 * pcim_enable_device - Managed pci_enable_device()
934 * @pdev: PCI device to be initialized
936 * Managed pci_enable_device().
938 int pcim_enable_device(struct pci_dev *pdev)
940 struct pci_devres *dr;
941 int rc;
943 dr = get_pci_dr(pdev);
944 if (unlikely(!dr))
945 return -ENOMEM;
946 if (dr->enabled)
947 return 0;
949 rc = pci_enable_device(pdev);
950 if (!rc) {
951 pdev->is_managed = 1;
952 dr->enabled = 1;
954 return rc;
958 * pcim_pin_device - Pin managed PCI device
959 * @pdev: PCI device to pin
961 * Pin managed PCI device @pdev. Pinned device won't be disabled on
962 * driver detach. @pdev must have been enabled with
963 * pcim_enable_device().
965 void pcim_pin_device(struct pci_dev *pdev)
967 struct pci_devres *dr;
969 dr = find_pci_dr(pdev);
970 WARN_ON(!dr || !dr->enabled);
971 if (dr)
972 dr->pinned = 1;
976 * pcibios_disable_device - disable arch specific PCI resources for device dev
977 * @dev: the PCI device to disable
979 * Disables architecture specific PCI resources for the device. This
980 * is the default implementation. Architecture implementations can
981 * override this.
983 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
986 * pci_disable_device - Disable PCI device after use
987 * @dev: PCI device to be disabled
989 * Signal to the system that the PCI device is not in use by the system
990 * anymore. This only involves disabling PCI bus-mastering, if active.
992 * Note we don't actually disable the device until all callers of
993 * pci_device_enable() have called pci_device_disable().
995 void
996 pci_disable_device(struct pci_dev *dev)
998 struct pci_devres *dr;
999 u16 pci_command;
1001 dr = find_pci_dr(dev);
1002 if (dr)
1003 dr->enabled = 0;
1005 if (atomic_sub_return(1, &dev->enable_cnt) != 0)
1006 return;
1008 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1009 if (pci_command & PCI_COMMAND_MASTER) {
1010 pci_command &= ~PCI_COMMAND_MASTER;
1011 pci_write_config_word(dev, PCI_COMMAND, pci_command);
1013 dev->is_busmaster = 0;
1015 pcibios_disable_device(dev);
1019 * pcibios_set_pcie_reset_state - set reset state for device dev
1020 * @dev: the PCI-E device reset
1021 * @state: Reset state to enter into
1024 * Sets the PCI-E reset state for the device. This is the default
1025 * implementation. Architecture implementations can override this.
1027 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
1028 enum pcie_reset_state state)
1030 return -EINVAL;
1034 * pci_set_pcie_reset_state - set reset state for device dev
1035 * @dev: the PCI-E device reset
1036 * @state: Reset state to enter into
1039 * Sets the PCI reset state for the device.
1041 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1043 return pcibios_set_pcie_reset_state(dev, state);
1047 * pci_pme_capable - check the capability of PCI device to generate PME#
1048 * @dev: PCI device to handle.
1049 * @state: PCI state from which device will issue PME#.
1051 bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1053 if (!dev->pm_cap)
1054 return false;
1056 return !!(dev->pme_support & (1 << state));
1060 * pci_pme_active - enable or disable PCI device's PME# function
1061 * @dev: PCI device to handle.
1062 * @enable: 'true' to enable PME# generation; 'false' to disable it.
1064 * The caller must verify that the device is capable of generating PME# before
1065 * calling this function with @enable equal to 'true'.
1067 void pci_pme_active(struct pci_dev *dev, bool enable)
1069 u16 pmcsr;
1071 if (!dev->pm_cap)
1072 return;
1074 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1075 /* Clear PME_Status by writing 1 to it and enable PME# */
1076 pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1077 if (!enable)
1078 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1080 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1082 dev_printk(KERN_INFO, &dev->dev, "PME# %s\n",
1083 enable ? "enabled" : "disabled");
1087 * pci_enable_wake - enable PCI device as wakeup event source
1088 * @dev: PCI device affected
1089 * @state: PCI state from which device will issue wakeup events
1090 * @enable: True to enable event generation; false to disable
1092 * This enables the device as a wakeup event source, or disables it.
1093 * When such events involves platform-specific hooks, those hooks are
1094 * called automatically by this routine.
1096 * Devices with legacy power management (no standard PCI PM capabilities)
1097 * always require such platform hooks.
1099 * RETURN VALUE:
1100 * 0 is returned on success
1101 * -EINVAL is returned if device is not supposed to wake up the system
1102 * Error code depending on the platform is returned if both the platform and
1103 * the native mechanism fail to enable the generation of wake-up events
1105 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
1107 int error = 0;
1108 bool pme_done = false;
1110 if (!device_may_wakeup(&dev->dev))
1111 return -EINVAL;
1114 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1115 * Anderson we should be doing PME# wake enable followed by ACPI wake
1116 * enable. To disable wake-up we call the platform first, for symmetry.
1119 if (!enable && platform_pci_can_wakeup(dev))
1120 error = platform_pci_sleep_wake(dev, false);
1122 if (!enable || pci_pme_capable(dev, state)) {
1123 pci_pme_active(dev, enable);
1124 pme_done = true;
1127 if (enable && platform_pci_can_wakeup(dev))
1128 error = platform_pci_sleep_wake(dev, true);
1130 return pme_done ? 0 : error;
1134 * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1135 * @dev: PCI device to prepare
1136 * @enable: True to enable wake-up event generation; false to disable
1138 * Many drivers want the device to wake up the system from D3_hot or D3_cold
1139 * and this function allows them to set that up cleanly - pci_enable_wake()
1140 * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1141 * ordering constraints.
1143 * This function only returns error code if the device is not capable of
1144 * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1145 * enable wake-up power for it.
1147 int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1149 return pci_pme_capable(dev, PCI_D3cold) ?
1150 pci_enable_wake(dev, PCI_D3cold, enable) :
1151 pci_enable_wake(dev, PCI_D3hot, enable);
1155 * pci_target_state - find an appropriate low power state for a given PCI dev
1156 * @dev: PCI device
1158 * Use underlying platform code to find a supported low power state for @dev.
1159 * If the platform can't manage @dev, return the deepest state from which it
1160 * can generate wake events, based on any available PME info.
1162 pci_power_t pci_target_state(struct pci_dev *dev)
1164 pci_power_t target_state = PCI_D3hot;
1166 if (platform_pci_power_manageable(dev)) {
1168 * Call the platform to choose the target state of the device
1169 * and enable wake-up from this state if supported.
1171 pci_power_t state = platform_pci_choose_state(dev);
1173 switch (state) {
1174 case PCI_POWER_ERROR:
1175 case PCI_UNKNOWN:
1176 break;
1177 case PCI_D1:
1178 case PCI_D2:
1179 if (pci_no_d1d2(dev))
1180 break;
1181 default:
1182 target_state = state;
1184 } else if (device_may_wakeup(&dev->dev)) {
1186 * Find the deepest state from which the device can generate
1187 * wake-up events, make it the target state and enable device
1188 * to generate PME#.
1190 if (!dev->pm_cap)
1191 return PCI_POWER_ERROR;
1193 if (dev->pme_support) {
1194 while (target_state
1195 && !(dev->pme_support & (1 << target_state)))
1196 target_state--;
1200 return target_state;
1204 * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1205 * @dev: Device to handle.
1207 * Choose the power state appropriate for the device depending on whether
1208 * it can wake up the system and/or is power manageable by the platform
1209 * (PCI_D3hot is the default) and put the device into that state.
1211 int pci_prepare_to_sleep(struct pci_dev *dev)
1213 pci_power_t target_state = pci_target_state(dev);
1214 int error;
1216 if (target_state == PCI_POWER_ERROR)
1217 return -EIO;
1219 pci_enable_wake(dev, target_state, true);
1221 error = pci_set_power_state(dev, target_state);
1223 if (error)
1224 pci_enable_wake(dev, target_state, false);
1226 return error;
1230 * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1231 * @dev: Device to handle.
1233 * Disable device's sytem wake-up capability and put it into D0.
1235 int pci_back_from_sleep(struct pci_dev *dev)
1237 pci_enable_wake(dev, PCI_D0, false);
1238 return pci_set_power_state(dev, PCI_D0);
1242 * pci_pm_init - Initialize PM functions of given PCI device
1243 * @dev: PCI device to handle.
1245 void pci_pm_init(struct pci_dev *dev)
1247 int pm;
1248 u16 pmc;
1250 dev->pm_cap = 0;
1252 /* find PCI PM capability in list */
1253 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
1254 if (!pm)
1255 return;
1256 /* Check device's ability to generate PME# */
1257 pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
1259 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
1260 dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
1261 pmc & PCI_PM_CAP_VER_MASK);
1262 return;
1265 dev->pm_cap = pm;
1267 dev->d1_support = false;
1268 dev->d2_support = false;
1269 if (!pci_no_d1d2(dev)) {
1270 if (pmc & PCI_PM_CAP_D1)
1271 dev->d1_support = true;
1272 if (pmc & PCI_PM_CAP_D2)
1273 dev->d2_support = true;
1275 if (dev->d1_support || dev->d2_support)
1276 dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
1277 dev->d1_support ? " D1" : "",
1278 dev->d2_support ? " D2" : "");
1281 pmc &= PCI_PM_CAP_PME_MASK;
1282 if (pmc) {
1283 dev_info(&dev->dev, "PME# supported from%s%s%s%s%s\n",
1284 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
1285 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
1286 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
1287 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
1288 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
1289 dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
1291 * Make device's PM flags reflect the wake-up capability, but
1292 * let the user space enable it to wake up the system as needed.
1294 device_set_wakeup_capable(&dev->dev, true);
1295 device_set_wakeup_enable(&dev->dev, false);
1296 /* Disable the PME# generation functionality */
1297 pci_pme_active(dev, false);
1298 } else {
1299 dev->pme_support = 0;
1304 * pci_enable_ari - enable ARI forwarding if hardware support it
1305 * @dev: the PCI device
1307 void pci_enable_ari(struct pci_dev *dev)
1309 int pos;
1310 u32 cap;
1311 u16 ctrl;
1312 struct pci_dev *bridge;
1314 if (!dev->is_pcie || dev->devfn)
1315 return;
1317 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1318 if (!pos)
1319 return;
1321 bridge = dev->bus->self;
1322 if (!bridge || !bridge->is_pcie)
1323 return;
1325 pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
1326 if (!pos)
1327 return;
1329 pci_read_config_dword(bridge, pos + PCI_EXP_DEVCAP2, &cap);
1330 if (!(cap & PCI_EXP_DEVCAP2_ARI))
1331 return;
1333 pci_read_config_word(bridge, pos + PCI_EXP_DEVCTL2, &ctrl);
1334 ctrl |= PCI_EXP_DEVCTL2_ARI;
1335 pci_write_config_word(bridge, pos + PCI_EXP_DEVCTL2, ctrl);
1337 bridge->ari_enabled = 1;
1341 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
1343 u8 pin;
1345 pin = dev->pin;
1346 if (!pin)
1347 return -1;
1348 pin--;
1349 while (dev->bus->self) {
1350 pin = (pin + PCI_SLOT(dev->devfn)) % 4;
1351 dev = dev->bus->self;
1353 *bridge = dev;
1354 return pin;
1358 * pci_release_region - Release a PCI bar
1359 * @pdev: PCI device whose resources were previously reserved by pci_request_region
1360 * @bar: BAR to release
1362 * Releases the PCI I/O and memory resources previously reserved by a
1363 * successful call to pci_request_region. Call this function only
1364 * after all use of the PCI regions has ceased.
1366 void pci_release_region(struct pci_dev *pdev, int bar)
1368 struct pci_devres *dr;
1370 if (pci_resource_len(pdev, bar) == 0)
1371 return;
1372 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1373 release_region(pci_resource_start(pdev, bar),
1374 pci_resource_len(pdev, bar));
1375 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1376 release_mem_region(pci_resource_start(pdev, bar),
1377 pci_resource_len(pdev, bar));
1379 dr = find_pci_dr(pdev);
1380 if (dr)
1381 dr->region_mask &= ~(1 << bar);
1385 * pci_request_region - Reserved PCI I/O and memory resource
1386 * @pdev: PCI device whose resources are to be reserved
1387 * @bar: BAR to be reserved
1388 * @res_name: Name to be associated with resource.
1390 * Mark the PCI region associated with PCI device @pdev BR @bar as
1391 * being reserved by owner @res_name. Do not access any
1392 * address inside the PCI regions unless this call returns
1393 * successfully.
1395 * Returns 0 on success, or %EBUSY on error. A warning
1396 * message is also printed on failure.
1398 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1400 struct pci_devres *dr;
1402 if (pci_resource_len(pdev, bar) == 0)
1403 return 0;
1405 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1406 if (!request_region(pci_resource_start(pdev, bar),
1407 pci_resource_len(pdev, bar), res_name))
1408 goto err_out;
1410 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1411 if (!request_mem_region(pci_resource_start(pdev, bar),
1412 pci_resource_len(pdev, bar), res_name))
1413 goto err_out;
1416 dr = find_pci_dr(pdev);
1417 if (dr)
1418 dr->region_mask |= 1 << bar;
1420 return 0;
1422 err_out:
1423 dev_warn(&pdev->dev, "BAR %d: can't reserve %s region %pR\n",
1424 bar,
1425 pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
1426 &pdev->resource[bar]);
1427 return -EBUSY;
1431 * pci_release_selected_regions - Release selected PCI I/O and memory resources
1432 * @pdev: PCI device whose resources were previously reserved
1433 * @bars: Bitmask of BARs to be released
1435 * Release selected PCI I/O and memory resources previously reserved.
1436 * Call this function only after all use of the PCI regions has ceased.
1438 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1440 int i;
1442 for (i = 0; i < 6; i++)
1443 if (bars & (1 << i))
1444 pci_release_region(pdev, i);
1448 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
1449 * @pdev: PCI device whose resources are to be reserved
1450 * @bars: Bitmask of BARs to be requested
1451 * @res_name: Name to be associated with resource
1453 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
1454 const char *res_name)
1456 int i;
1458 for (i = 0; i < 6; i++)
1459 if (bars & (1 << i))
1460 if(pci_request_region(pdev, i, res_name))
1461 goto err_out;
1462 return 0;
1464 err_out:
1465 while(--i >= 0)
1466 if (bars & (1 << i))
1467 pci_release_region(pdev, i);
1469 return -EBUSY;
1473 * pci_release_regions - Release reserved PCI I/O and memory resources
1474 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
1476 * Releases all PCI I/O and memory resources previously reserved by a
1477 * successful call to pci_request_regions. Call this function only
1478 * after all use of the PCI regions has ceased.
1481 void pci_release_regions(struct pci_dev *pdev)
1483 pci_release_selected_regions(pdev, (1 << 6) - 1);
1487 * pci_request_regions - Reserved PCI I/O and memory resources
1488 * @pdev: PCI device whose resources are to be reserved
1489 * @res_name: Name to be associated with resource.
1491 * Mark all PCI regions associated with PCI device @pdev as
1492 * being reserved by owner @res_name. Do not access any
1493 * address inside the PCI regions unless this call returns
1494 * successfully.
1496 * Returns 0 on success, or %EBUSY on error. A warning
1497 * message is also printed on failure.
1499 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
1501 return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
1505 * pci_set_master - enables bus-mastering for device dev
1506 * @dev: the PCI device to enable
1508 * Enables bus-mastering on the device and calls pcibios_set_master()
1509 * to do the needed arch specific settings.
1511 void
1512 pci_set_master(struct pci_dev *dev)
1514 u16 cmd;
1516 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1517 if (! (cmd & PCI_COMMAND_MASTER)) {
1518 dev_dbg(&dev->dev, "enabling bus mastering\n");
1519 cmd |= PCI_COMMAND_MASTER;
1520 pci_write_config_word(dev, PCI_COMMAND, cmd);
1522 dev->is_busmaster = 1;
1523 pcibios_set_master(dev);
1526 #ifdef PCI_DISABLE_MWI
1527 int pci_set_mwi(struct pci_dev *dev)
1529 return 0;
1532 int pci_try_set_mwi(struct pci_dev *dev)
1534 return 0;
1537 void pci_clear_mwi(struct pci_dev *dev)
1541 #else
1543 #ifndef PCI_CACHE_LINE_BYTES
1544 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
1545 #endif
1547 /* This can be overridden by arch code. */
1548 /* Don't forget this is measured in 32-bit words, not bytes */
1549 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
1552 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1553 * @dev: the PCI device for which MWI is to be enabled
1555 * Helper function for pci_set_mwi.
1556 * Originally copied from drivers/net/acenic.c.
1557 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1559 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1561 static int
1562 pci_set_cacheline_size(struct pci_dev *dev)
1564 u8 cacheline_size;
1566 if (!pci_cache_line_size)
1567 return -EINVAL; /* The system doesn't support MWI. */
1569 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1570 equal to or multiple of the right value. */
1571 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1572 if (cacheline_size >= pci_cache_line_size &&
1573 (cacheline_size % pci_cache_line_size) == 0)
1574 return 0;
1576 /* Write the correct value. */
1577 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1578 /* Read it back. */
1579 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1580 if (cacheline_size == pci_cache_line_size)
1581 return 0;
1583 dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
1584 "supported\n", pci_cache_line_size << 2);
1586 return -EINVAL;
1590 * pci_set_mwi - enables memory-write-invalidate PCI transaction
1591 * @dev: the PCI device for which MWI is enabled
1593 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1595 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1598 pci_set_mwi(struct pci_dev *dev)
1600 int rc;
1601 u16 cmd;
1603 rc = pci_set_cacheline_size(dev);
1604 if (rc)
1605 return rc;
1607 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1608 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1609 dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
1610 cmd |= PCI_COMMAND_INVALIDATE;
1611 pci_write_config_word(dev, PCI_COMMAND, cmd);
1614 return 0;
1618 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
1619 * @dev: the PCI device for which MWI is enabled
1621 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1622 * Callers are not required to check the return value.
1624 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1626 int pci_try_set_mwi(struct pci_dev *dev)
1628 int rc = pci_set_mwi(dev);
1629 return rc;
1633 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1634 * @dev: the PCI device to disable
1636 * Disables PCI Memory-Write-Invalidate transaction on the device
1638 void
1639 pci_clear_mwi(struct pci_dev *dev)
1641 u16 cmd;
1643 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1644 if (cmd & PCI_COMMAND_INVALIDATE) {
1645 cmd &= ~PCI_COMMAND_INVALIDATE;
1646 pci_write_config_word(dev, PCI_COMMAND, cmd);
1649 #endif /* ! PCI_DISABLE_MWI */
1652 * pci_intx - enables/disables PCI INTx for device dev
1653 * @pdev: the PCI device to operate on
1654 * @enable: boolean: whether to enable or disable PCI INTx
1656 * Enables/disables PCI INTx for device dev
1658 void
1659 pci_intx(struct pci_dev *pdev, int enable)
1661 u16 pci_command, new;
1663 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1665 if (enable) {
1666 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1667 } else {
1668 new = pci_command | PCI_COMMAND_INTX_DISABLE;
1671 if (new != pci_command) {
1672 struct pci_devres *dr;
1674 pci_write_config_word(pdev, PCI_COMMAND, new);
1676 dr = find_pci_dr(pdev);
1677 if (dr && !dr->restore_intx) {
1678 dr->restore_intx = 1;
1679 dr->orig_intx = !enable;
1685 * pci_msi_off - disables any msi or msix capabilities
1686 * @dev: the PCI device to operate on
1688 * If you want to use msi see pci_enable_msi and friends.
1689 * This is a lower level primitive that allows us to disable
1690 * msi operation at the device level.
1692 void pci_msi_off(struct pci_dev *dev)
1694 int pos;
1695 u16 control;
1697 pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
1698 if (pos) {
1699 pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
1700 control &= ~PCI_MSI_FLAGS_ENABLE;
1701 pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
1703 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1704 if (pos) {
1705 pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
1706 control &= ~PCI_MSIX_FLAGS_ENABLE;
1707 pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
1711 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
1713 * These can be overridden by arch-specific implementations
1716 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
1718 if (!pci_dma_supported(dev, mask))
1719 return -EIO;
1721 dev->dma_mask = mask;
1723 return 0;
1727 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
1729 if (!pci_dma_supported(dev, mask))
1730 return -EIO;
1732 dev->dev.coherent_dma_mask = mask;
1734 return 0;
1736 #endif
1738 #ifndef HAVE_ARCH_PCI_SET_DMA_MAX_SEGMENT_SIZE
1739 int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
1741 return dma_set_max_seg_size(&dev->dev, size);
1743 EXPORT_SYMBOL(pci_set_dma_max_seg_size);
1744 #endif
1746 #ifndef HAVE_ARCH_PCI_SET_DMA_SEGMENT_BOUNDARY
1747 int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
1749 return dma_set_seg_boundary(&dev->dev, mask);
1751 EXPORT_SYMBOL(pci_set_dma_seg_boundary);
1752 #endif
1755 * pci_execute_reset_function() - Reset a PCI device function
1756 * @dev: Device function to reset
1758 * Some devices allow an individual function to be reset without affecting
1759 * other functions in the same device. The PCI device must be responsive
1760 * to PCI config space in order to use this function.
1762 * The device function is presumed to be unused when this function is called.
1763 * Resetting the device will make the contents of PCI configuration space
1764 * random, so any caller of this must be prepared to reinitialise the
1765 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
1766 * etc.
1768 * Returns 0 if the device function was successfully reset or -ENOTTY if the
1769 * device doesn't support resetting a single function.
1771 int pci_execute_reset_function(struct pci_dev *dev)
1773 u16 status;
1774 u32 cap;
1775 int exppos = pci_find_capability(dev, PCI_CAP_ID_EXP);
1777 if (!exppos)
1778 return -ENOTTY;
1779 pci_read_config_dword(dev, exppos + PCI_EXP_DEVCAP, &cap);
1780 if (!(cap & PCI_EXP_DEVCAP_FLR))
1781 return -ENOTTY;
1783 pci_block_user_cfg_access(dev);
1785 /* Wait for Transaction Pending bit clean */
1786 msleep(100);
1787 pci_read_config_word(dev, exppos + PCI_EXP_DEVSTA, &status);
1788 if (status & PCI_EXP_DEVSTA_TRPND) {
1789 dev_info(&dev->dev, "Busy after 100ms while trying to reset; "
1790 "sleeping for 1 second\n");
1791 ssleep(1);
1792 pci_read_config_word(dev, exppos + PCI_EXP_DEVSTA, &status);
1793 if (status & PCI_EXP_DEVSTA_TRPND)
1794 dev_info(&dev->dev, "Still busy after 1s; "
1795 "proceeding with reset anyway\n");
1798 pci_write_config_word(dev, exppos + PCI_EXP_DEVCTL,
1799 PCI_EXP_DEVCTL_BCR_FLR);
1800 mdelay(100);
1802 pci_unblock_user_cfg_access(dev);
1803 return 0;
1805 EXPORT_SYMBOL_GPL(pci_execute_reset_function);
1808 * pci_reset_function() - quiesce and reset a PCI device function
1809 * @dev: Device function to reset
1811 * Some devices allow an individual function to be reset without affecting
1812 * other functions in the same device. The PCI device must be responsive
1813 * to PCI config space in order to use this function.
1815 * This function does not just reset the PCI portion of a device, but
1816 * clears all the state associated with the device. This function differs
1817 * from pci_execute_reset_function in that it saves and restores device state
1818 * over the reset.
1820 * Returns 0 if the device function was successfully reset or -ENOTTY if the
1821 * device doesn't support resetting a single function.
1823 int pci_reset_function(struct pci_dev *dev)
1825 u32 cap;
1826 int exppos = pci_find_capability(dev, PCI_CAP_ID_EXP);
1827 int r;
1829 if (!exppos)
1830 return -ENOTTY;
1831 pci_read_config_dword(dev, exppos + PCI_EXP_DEVCAP, &cap);
1832 if (!(cap & PCI_EXP_DEVCAP_FLR))
1833 return -ENOTTY;
1835 if (!dev->msi_enabled && !dev->msix_enabled)
1836 disable_irq(dev->irq);
1837 pci_save_state(dev);
1839 pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
1841 r = pci_execute_reset_function(dev);
1843 pci_restore_state(dev);
1844 if (!dev->msi_enabled && !dev->msix_enabled)
1845 enable_irq(dev->irq);
1847 return r;
1849 EXPORT_SYMBOL_GPL(pci_reset_function);
1852 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
1853 * @dev: PCI device to query
1855 * Returns mmrbc: maximum designed memory read count in bytes
1856 * or appropriate error value.
1858 int pcix_get_max_mmrbc(struct pci_dev *dev)
1860 int err, cap;
1861 u32 stat;
1863 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1864 if (!cap)
1865 return -EINVAL;
1867 err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
1868 if (err)
1869 return -EINVAL;
1871 return (stat & PCI_X_STATUS_MAX_READ) >> 12;
1873 EXPORT_SYMBOL(pcix_get_max_mmrbc);
1876 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
1877 * @dev: PCI device to query
1879 * Returns mmrbc: maximum memory read count in bytes
1880 * or appropriate error value.
1882 int pcix_get_mmrbc(struct pci_dev *dev)
1884 int ret, cap;
1885 u32 cmd;
1887 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1888 if (!cap)
1889 return -EINVAL;
1891 ret = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
1892 if (!ret)
1893 ret = 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
1895 return ret;
1897 EXPORT_SYMBOL(pcix_get_mmrbc);
1900 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
1901 * @dev: PCI device to query
1902 * @mmrbc: maximum memory read count in bytes
1903 * valid values are 512, 1024, 2048, 4096
1905 * If possible sets maximum memory read byte count, some bridges have erratas
1906 * that prevent this.
1908 int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
1910 int cap, err = -EINVAL;
1911 u32 stat, cmd, v, o;
1913 if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
1914 goto out;
1916 v = ffs(mmrbc) - 10;
1918 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1919 if (!cap)
1920 goto out;
1922 err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
1923 if (err)
1924 goto out;
1926 if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
1927 return -E2BIG;
1929 err = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
1930 if (err)
1931 goto out;
1933 o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
1934 if (o != v) {
1935 if (v > o && dev->bus &&
1936 (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
1937 return -EIO;
1939 cmd &= ~PCI_X_CMD_MAX_READ;
1940 cmd |= v << 2;
1941 err = pci_write_config_dword(dev, cap + PCI_X_CMD, cmd);
1943 out:
1944 return err;
1946 EXPORT_SYMBOL(pcix_set_mmrbc);
1949 * pcie_get_readrq - get PCI Express read request size
1950 * @dev: PCI device to query
1952 * Returns maximum memory read request in bytes
1953 * or appropriate error value.
1955 int pcie_get_readrq(struct pci_dev *dev)
1957 int ret, cap;
1958 u16 ctl;
1960 cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
1961 if (!cap)
1962 return -EINVAL;
1964 ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
1965 if (!ret)
1966 ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
1968 return ret;
1970 EXPORT_SYMBOL(pcie_get_readrq);
1973 * pcie_set_readrq - set PCI Express maximum memory read request
1974 * @dev: PCI device to query
1975 * @rq: maximum memory read count in bytes
1976 * valid values are 128, 256, 512, 1024, 2048, 4096
1978 * If possible sets maximum read byte count
1980 int pcie_set_readrq(struct pci_dev *dev, int rq)
1982 int cap, err = -EINVAL;
1983 u16 ctl, v;
1985 if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
1986 goto out;
1988 v = (ffs(rq) - 8) << 12;
1990 cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
1991 if (!cap)
1992 goto out;
1994 err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
1995 if (err)
1996 goto out;
1998 if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
1999 ctl &= ~PCI_EXP_DEVCTL_READRQ;
2000 ctl |= v;
2001 err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
2004 out:
2005 return err;
2007 EXPORT_SYMBOL(pcie_set_readrq);
2010 * pci_select_bars - Make BAR mask from the type of resource
2011 * @dev: the PCI device for which BAR mask is made
2012 * @flags: resource type mask to be selected
2014 * This helper routine makes bar mask from the type of resource.
2016 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
2018 int i, bars = 0;
2019 for (i = 0; i < PCI_NUM_RESOURCES; i++)
2020 if (pci_resource_flags(dev, i) & flags)
2021 bars |= (1 << i);
2022 return bars;
2025 static void __devinit pci_no_domains(void)
2027 #ifdef CONFIG_PCI_DOMAINS
2028 pci_domains_supported = 0;
2029 #endif
2032 static int __devinit pci_init(void)
2034 struct pci_dev *dev = NULL;
2036 while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
2037 pci_fixup_device(pci_fixup_final, dev);
2040 msi_init();
2042 return 0;
2045 static int __devinit pci_setup(char *str)
2047 while (str) {
2048 char *k = strchr(str, ',');
2049 if (k)
2050 *k++ = 0;
2051 if (*str && (str = pcibios_setup(str)) && *str) {
2052 if (!strcmp(str, "nomsi")) {
2053 pci_no_msi();
2054 } else if (!strcmp(str, "noaer")) {
2055 pci_no_aer();
2056 } else if (!strcmp(str, "nodomains")) {
2057 pci_no_domains();
2058 } else if (!strncmp(str, "cbiosize=", 9)) {
2059 pci_cardbus_io_size = memparse(str + 9, &str);
2060 } else if (!strncmp(str, "cbmemsize=", 10)) {
2061 pci_cardbus_mem_size = memparse(str + 10, &str);
2062 } else {
2063 printk(KERN_ERR "PCI: Unknown option `%s'\n",
2064 str);
2067 str = k;
2069 return 0;
2071 early_param("pci", pci_setup);
2073 device_initcall(pci_init);
2075 EXPORT_SYMBOL(pci_reenable_device);
2076 EXPORT_SYMBOL(pci_enable_device_io);
2077 EXPORT_SYMBOL(pci_enable_device_mem);
2078 EXPORT_SYMBOL(pci_enable_device);
2079 EXPORT_SYMBOL(pcim_enable_device);
2080 EXPORT_SYMBOL(pcim_pin_device);
2081 EXPORT_SYMBOL(pci_disable_device);
2082 EXPORT_SYMBOL(pci_find_capability);
2083 EXPORT_SYMBOL(pci_bus_find_capability);
2084 EXPORT_SYMBOL(pci_release_regions);
2085 EXPORT_SYMBOL(pci_request_regions);
2086 EXPORT_SYMBOL(pci_release_region);
2087 EXPORT_SYMBOL(pci_request_region);
2088 EXPORT_SYMBOL(pci_release_selected_regions);
2089 EXPORT_SYMBOL(pci_request_selected_regions);
2090 EXPORT_SYMBOL(pci_set_master);
2091 EXPORT_SYMBOL(pci_set_mwi);
2092 EXPORT_SYMBOL(pci_try_set_mwi);
2093 EXPORT_SYMBOL(pci_clear_mwi);
2094 EXPORT_SYMBOL_GPL(pci_intx);
2095 EXPORT_SYMBOL(pci_set_dma_mask);
2096 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
2097 EXPORT_SYMBOL(pci_assign_resource);
2098 EXPORT_SYMBOL(pci_find_parent_resource);
2099 EXPORT_SYMBOL(pci_select_bars);
2101 EXPORT_SYMBOL(pci_set_power_state);
2102 EXPORT_SYMBOL(pci_save_state);
2103 EXPORT_SYMBOL(pci_restore_state);
2104 EXPORT_SYMBOL(pci_pme_capable);
2105 EXPORT_SYMBOL(pci_pme_active);
2106 EXPORT_SYMBOL(pci_enable_wake);
2107 EXPORT_SYMBOL(pci_wake_from_d3);
2108 EXPORT_SYMBOL(pci_target_state);
2109 EXPORT_SYMBOL(pci_prepare_to_sleep);
2110 EXPORT_SYMBOL(pci_back_from_sleep);
2111 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);