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[tomato.git] / release / src-rt-6.x / linux / linux-2.6 / drivers / pci / pci.c
blobfd47ac0c4730a96080e22151ed186c1ec4585725
1 /*
2 * $Id: pci.c,v 1.91 1999/01/21 13:34:01 davem Exp $
4 * PCI Bus Services, see include/linux/pci.h for further explanation.
6 * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
7 * David Mosberger-Tang
9 * Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
12 #include <linux/kernel.h>
13 #include <linux/delay.h>
14 #include <linux/init.h>
15 #include <linux/pci.h>
16 #include <linux/pm.h>
17 #include <linux/module.h>
18 #include <linux/spinlock.h>
19 #include <linux/string.h>
20 #include <asm/dma.h> /* isa_dma_bridge_buggy */
21 #include "pci.h"
23 unsigned int pci_pm_d3_delay = 10;
25 #define DEFAULT_CARDBUS_IO_SIZE (256)
26 #define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
27 /* pci=cbmemsize=nnM,cbiosize=nn can override this */
28 unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
29 unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
31 /**
32 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
33 * @bus: pointer to PCI bus structure to search
35 * Given a PCI bus, returns the highest PCI bus number present in the set
36 * including the given PCI bus and its list of child PCI buses.
38 unsigned char pci_bus_max_busnr(struct pci_bus* bus)
40 struct list_head *tmp;
41 unsigned char max, n;
43 max = bus->subordinate;
44 list_for_each(tmp, &bus->children) {
45 n = pci_bus_max_busnr(pci_bus_b(tmp));
46 if(n > max)
47 max = n;
49 return max;
51 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
53 #if 0
54 /**
55 * pci_max_busnr - returns maximum PCI bus number
57 * Returns the highest PCI bus number present in the system global list of
58 * PCI buses.
60 unsigned char __devinit
61 pci_max_busnr(void)
63 struct pci_bus *bus = NULL;
64 unsigned char max, n;
66 max = 0;
67 while ((bus = pci_find_next_bus(bus)) != NULL) {
68 n = pci_bus_max_busnr(bus);
69 if(n > max)
70 max = n;
72 return max;
75 #endif /* 0 */
77 #define PCI_FIND_CAP_TTL 48
79 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
80 u8 pos, int cap, int *ttl)
82 u8 id;
84 while ((*ttl)--) {
85 pci_bus_read_config_byte(bus, devfn, pos, &pos);
86 if (pos < 0x40)
87 break;
88 pos &= ~3;
89 pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
90 &id);
91 if (id == 0xff)
92 break;
93 if (id == cap)
94 return pos;
95 pos += PCI_CAP_LIST_NEXT;
97 return 0;
100 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
101 u8 pos, int cap)
103 int ttl = PCI_FIND_CAP_TTL;
105 return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
108 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
110 return __pci_find_next_cap(dev->bus, dev->devfn,
111 pos + PCI_CAP_LIST_NEXT, cap);
113 EXPORT_SYMBOL_GPL(pci_find_next_capability);
115 static int __pci_bus_find_cap_start(struct pci_bus *bus,
116 unsigned int devfn, u8 hdr_type)
118 u16 status;
120 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
121 if (!(status & PCI_STATUS_CAP_LIST))
122 return 0;
124 switch (hdr_type) {
125 case PCI_HEADER_TYPE_NORMAL:
126 case PCI_HEADER_TYPE_BRIDGE:
127 return PCI_CAPABILITY_LIST;
128 case PCI_HEADER_TYPE_CARDBUS:
129 return PCI_CB_CAPABILITY_LIST;
130 default:
131 return 0;
134 return 0;
138 * pci_find_capability - query for devices' capabilities
139 * @dev: PCI device to query
140 * @cap: capability code
142 * Tell if a device supports a given PCI capability.
143 * Returns the address of the requested capability structure within the
144 * device's PCI configuration space or 0 in case the device does not
145 * support it. Possible values for @cap:
147 * %PCI_CAP_ID_PM Power Management
148 * %PCI_CAP_ID_AGP Accelerated Graphics Port
149 * %PCI_CAP_ID_VPD Vital Product Data
150 * %PCI_CAP_ID_SLOTID Slot Identification
151 * %PCI_CAP_ID_MSI Message Signalled Interrupts
152 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
153 * %PCI_CAP_ID_PCIX PCI-X
154 * %PCI_CAP_ID_EXP PCI Express
156 int pci_find_capability(struct pci_dev *dev, int cap)
158 int pos;
160 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
161 if (pos)
162 pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
164 return pos;
168 * pci_bus_find_capability - query for devices' capabilities
169 * @bus: the PCI bus to query
170 * @devfn: PCI device to query
171 * @cap: capability code
173 * Like pci_find_capability() but works for pci devices that do not have a
174 * pci_dev structure set up yet.
176 * Returns the address of the requested capability structure within the
177 * device's PCI configuration space or 0 in case the device does not
178 * support it.
180 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
182 int pos;
183 u8 hdr_type;
185 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
187 pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
188 if (pos)
189 pos = __pci_find_next_cap(bus, devfn, pos, cap);
191 return pos;
195 * pci_find_ext_capability - Find an extended capability
196 * @dev: PCI device to query
197 * @cap: capability code
199 * Returns the address of the requested extended capability structure
200 * within the device's PCI configuration space or 0 if the device does
201 * not support it. Possible values for @cap:
203 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
204 * %PCI_EXT_CAP_ID_VC Virtual Channel
205 * %PCI_EXT_CAP_ID_DSN Device Serial Number
206 * %PCI_EXT_CAP_ID_PWR Power Budgeting
208 int pci_find_ext_capability(struct pci_dev *dev, int cap)
210 u32 header;
211 int ttl = 480; /* 3840 bytes, minimum 8 bytes per capability */
212 int pos = 0x100;
214 if (dev->cfg_size <= 256)
215 return 0;
217 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
218 return 0;
221 * If we have no capabilities, this is indicated by cap ID,
222 * cap version and next pointer all being 0.
224 if (header == 0)
225 return 0;
227 while (ttl-- > 0) {
228 if (PCI_EXT_CAP_ID(header) == cap)
229 return pos;
231 pos = PCI_EXT_CAP_NEXT(header);
232 if (pos < 0x100)
233 break;
235 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
236 break;
239 return 0;
241 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
243 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
245 int rc, ttl = PCI_FIND_CAP_TTL;
246 u8 cap, mask;
248 if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
249 mask = HT_3BIT_CAP_MASK;
250 else
251 mask = HT_5BIT_CAP_MASK;
253 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
254 PCI_CAP_ID_HT, &ttl);
255 while (pos) {
256 rc = pci_read_config_byte(dev, pos + 3, &cap);
257 if (rc != PCIBIOS_SUCCESSFUL)
258 return 0;
260 if ((cap & mask) == ht_cap)
261 return pos;
263 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
264 pos + PCI_CAP_LIST_NEXT,
265 PCI_CAP_ID_HT, &ttl);
268 return 0;
271 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
272 * @dev: PCI device to query
273 * @pos: Position from which to continue searching
274 * @ht_cap: Hypertransport capability code
276 * To be used in conjunction with pci_find_ht_capability() to search for
277 * all capabilities matching @ht_cap. @pos should always be a value returned
278 * from pci_find_ht_capability().
280 * NB. To be 100% safe against broken PCI devices, the caller should take
281 * steps to avoid an infinite loop.
283 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
285 return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
287 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
290 * pci_find_ht_capability - query a device's Hypertransport capabilities
291 * @dev: PCI device to query
292 * @ht_cap: Hypertransport capability code
294 * Tell if a device supports a given Hypertransport capability.
295 * Returns an address within the device's PCI configuration space
296 * or 0 in case the device does not support the request capability.
297 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
298 * which has a Hypertransport capability matching @ht_cap.
300 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
302 int pos;
304 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
305 if (pos)
306 pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
308 return pos;
310 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
313 * pci_find_parent_resource - return resource region of parent bus of given region
314 * @dev: PCI device structure contains resources to be searched
315 * @res: child resource record for which parent is sought
317 * For given resource region of given device, return the resource
318 * region of parent bus the given region is contained in or where
319 * it should be allocated from.
321 struct resource *
322 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
324 const struct pci_bus *bus = dev->bus;
325 int i;
326 struct resource *best = NULL;
328 for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
329 struct resource *r = bus->resource[i];
330 if (!r)
331 continue;
332 if (res->start && !(res->start >= r->start && res->end <= r->end))
333 continue; /* Not contained */
334 if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
335 continue; /* Wrong type */
336 if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
337 return r; /* Exact match */
338 if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
339 best = r; /* Approximating prefetchable by non-prefetchable */
341 return best;
345 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
346 * @dev: PCI device to have its BARs restored
348 * Restore the BAR values for a given device, so as to make it
349 * accessible by its driver.
351 void
352 pci_restore_bars(struct pci_dev *dev)
354 int i, numres;
356 switch (dev->hdr_type) {
357 case PCI_HEADER_TYPE_NORMAL:
358 numres = 6;
359 break;
360 case PCI_HEADER_TYPE_BRIDGE:
361 numres = 2;
362 break;
363 case PCI_HEADER_TYPE_CARDBUS:
364 numres = 1;
365 break;
366 default:
367 /* Should never get here, but just in case... */
368 return;
371 for (i = 0; i < numres; i ++)
372 pci_update_resource(dev, &dev->resource[i], i);
375 int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t t);
378 * pci_set_power_state - Set the power state of a PCI device
379 * @dev: PCI device to be suspended
380 * @state: PCI power state (D0, D1, D2, D3hot, D3cold) we're entering
382 * Transition a device to a new power state, using the Power Management
383 * Capabilities in the device's config space.
385 * RETURN VALUE:
386 * -EINVAL if trying to enter a lower state than we're already in.
387 * 0 if we're already in the requested state.
388 * -EIO if device does not support PCI PM.
389 * 0 if we can successfully change the power state.
392 pci_set_power_state(struct pci_dev *dev, pci_power_t state)
394 int pm, need_restore = 0;
395 u16 pmcsr, pmc;
397 /* bound the state we're entering */
398 if (state > PCI_D3hot)
399 state = PCI_D3hot;
402 * If the device or the parent bridge can't support PCI PM, ignore
403 * the request if we're doing anything besides putting it into D0
404 * (which would only happen on boot).
406 if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
407 return 0;
409 /* Validate current state:
410 * Can enter D0 from any state, but if we can only go deeper
411 * to sleep if we're already in a low power state
413 if (state != PCI_D0 && dev->current_state > state) {
414 printk(KERN_ERR "%s(): %s: state=%d, current state=%d\n",
415 __FUNCTION__, pci_name(dev), state, dev->current_state);
416 return -EINVAL;
417 } else if (dev->current_state == state)
418 return 0; /* we're already there */
421 /* find PCI PM capability in list */
422 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
424 /* abort if the device doesn't support PM capabilities */
425 if (!pm)
426 return -EIO;
428 pci_read_config_word(dev,pm + PCI_PM_PMC,&pmc);
429 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
430 printk(KERN_DEBUG
431 "PCI: %s has unsupported PM cap regs version (%u)\n",
432 pci_name(dev), pmc & PCI_PM_CAP_VER_MASK);
433 return -EIO;
436 /* check if this device supports the desired state */
437 if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
438 return -EIO;
439 else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2))
440 return -EIO;
442 pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
444 /* If we're (effectively) in D3, force entire word to 0.
445 * This doesn't affect PME_Status, disables PME_En, and
446 * sets PowerState to 0.
448 switch (dev->current_state) {
449 case PCI_D0:
450 case PCI_D1:
451 case PCI_D2:
452 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
453 pmcsr |= state;
454 break;
455 case PCI_UNKNOWN: /* Boot-up */
456 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
457 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
458 need_restore = 1;
459 /* Fall-through: force to D0 */
460 default:
461 pmcsr = 0;
462 break;
465 /* enter specified state */
466 pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
468 /* Mandatory power management transition delays */
469 /* see PCI PM 1.1 5.6.1 table 18 */
470 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
471 msleep(pci_pm_d3_delay);
472 else if (state == PCI_D2 || dev->current_state == PCI_D2)
473 udelay(200);
476 * Give firmware a chance to be called, such as ACPI _PRx, _PSx
477 * Firmware method after native method ?
479 if (platform_pci_set_power_state)
480 platform_pci_set_power_state(dev, state);
482 dev->current_state = state;
484 /* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
485 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
486 * from D3hot to D0 _may_ perform an internal reset, thereby
487 * going to "D0 Uninitialized" rather than "D0 Initialized".
488 * For example, at least some versions of the 3c905B and the
489 * 3c556B exhibit this behaviour.
491 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
492 * devices in a D3hot state at boot. Consequently, we need to
493 * restore at least the BARs so that the device will be
494 * accessible to its driver.
496 if (need_restore)
497 pci_restore_bars(dev);
499 return 0;
502 int (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
505 * pci_choose_state - Choose the power state of a PCI device
506 * @dev: PCI device to be suspended
507 * @state: target sleep state for the whole system. This is the value
508 * that is passed to suspend() function.
510 * Returns PCI power state suitable for given device and given system
511 * message.
514 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
516 int ret;
518 if (!pci_find_capability(dev, PCI_CAP_ID_PM))
519 return PCI_D0;
521 if (platform_pci_choose_state) {
522 ret = platform_pci_choose_state(dev, state);
523 if (ret >= 0)
524 state.event = ret;
527 switch (state.event) {
528 case PM_EVENT_ON:
529 return PCI_D0;
530 case PM_EVENT_FREEZE:
531 case PM_EVENT_PRETHAW:
532 /* REVISIT both freeze and pre-thaw "should" use D0 */
533 case PM_EVENT_SUSPEND:
534 return PCI_D3hot;
535 default:
536 printk("Unrecognized suspend event %d\n", state.event);
537 BUG();
539 return PCI_D0;
542 EXPORT_SYMBOL(pci_choose_state);
544 static int pci_save_pcie_state(struct pci_dev *dev)
546 int pos, i = 0;
547 struct pci_cap_saved_state *save_state;
548 u16 *cap;
550 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
551 if (pos <= 0)
552 return 0;
554 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
555 if (!save_state)
556 save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);
557 if (!save_state) {
558 dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
559 return -ENOMEM;
561 cap = (u16 *)&save_state->data[0];
563 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
564 pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
565 pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
566 pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
567 pci_add_saved_cap(dev, save_state);
568 return 0;
571 static void pci_restore_pcie_state(struct pci_dev *dev)
573 int i = 0, pos;
574 struct pci_cap_saved_state *save_state;
575 u16 *cap;
577 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
578 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
579 if (!save_state || pos <= 0)
580 return;
581 cap = (u16 *)&save_state->data[0];
583 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
584 pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
585 pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
586 pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
590 static int pci_save_pcix_state(struct pci_dev *dev)
592 int pos, i = 0;
593 struct pci_cap_saved_state *save_state;
594 u16 *cap;
596 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
597 if (pos <= 0)
598 return 0;
600 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
601 if (!save_state)
602 save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);
603 if (!save_state) {
604 dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
605 return -ENOMEM;
607 cap = (u16 *)&save_state->data[0];
609 pci_read_config_word(dev, pos + PCI_X_CMD, &cap[i++]);
610 pci_add_saved_cap(dev, save_state);
611 return 0;
614 static void pci_restore_pcix_state(struct pci_dev *dev)
616 int i = 0, pos;
617 struct pci_cap_saved_state *save_state;
618 u16 *cap;
620 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
621 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
622 if (!save_state || pos <= 0)
623 return;
624 cap = (u16 *)&save_state->data[0];
626 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
631 * pci_save_state - save the PCI configuration space of a device before suspending
632 * @dev: - PCI device that we're dealing with
635 pci_save_state(struct pci_dev *dev)
637 int i;
638 /* XXX: 100% dword access ok here? */
639 for (i = 0; i < 16; i++)
640 pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
641 if ((i = pci_save_pcie_state(dev)) != 0)
642 return i;
643 if ((i = pci_save_pcix_state(dev)) != 0)
644 return i;
645 return 0;
648 /**
649 * pci_restore_state - Restore the saved state of a PCI device
650 * @dev: - PCI device that we're dealing with
652 int
653 pci_restore_state(struct pci_dev *dev)
655 int i;
656 int val;
658 /* PCI Express register must be restored first */
659 pci_restore_pcie_state(dev);
662 * The Base Address register should be programmed before the command
663 * register(s)
665 for (i = 15; i >= 0; i--) {
666 pci_read_config_dword(dev, i * 4, &val);
667 if (val != dev->saved_config_space[i]) {
668 printk(KERN_DEBUG "PM: Writing back config space on "
669 "device %s at offset %x (was %x, writing %x)\n",
670 pci_name(dev), i,
671 val, (int)dev->saved_config_space[i]);
672 pci_write_config_dword(dev,i * 4,
673 dev->saved_config_space[i]);
676 pci_restore_pcix_state(dev);
677 pci_restore_msi_state(dev);
679 return 0;
682 static int do_pci_enable_device(struct pci_dev *dev, int bars)
684 int err;
686 err = pci_set_power_state(dev, PCI_D0);
687 if (err < 0 && err != -EIO)
688 return err;
689 err = pcibios_enable_device(dev, bars);
690 if (err < 0)
691 return err;
692 pci_fixup_device(pci_fixup_enable, dev);
694 return 0;
698 * __pci_reenable_device - Resume abandoned device
699 * @dev: PCI device to be resumed
701 * Note this function is a backend of pci_default_resume and is not supposed
702 * to be called by normal code, write proper resume handler and use it instead.
705 __pci_reenable_device(struct pci_dev *dev)
707 if (atomic_read(&dev->enable_cnt))
708 return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
709 return 0;
713 * pci_enable_device_bars - Initialize some of a device for use
714 * @dev: PCI device to be initialized
715 * @bars: bitmask of BAR's that must be configured
717 * Initialize device before it's used by a driver. Ask low-level code
718 * to enable selected I/O and memory resources. Wake up the device if it
719 * was suspended. Beware, this function can fail.
722 pci_enable_device_bars(struct pci_dev *dev, int bars)
724 int err;
726 if (atomic_add_return(1, &dev->enable_cnt) > 1)
727 return 0; /* already enabled */
729 err = do_pci_enable_device(dev, bars);
730 if (err < 0)
731 atomic_dec(&dev->enable_cnt);
732 return err;
736 * pci_enable_device - Initialize device before it's used by a driver.
737 * @dev: PCI device to be initialized
739 * Initialize device before it's used by a driver. Ask low-level code
740 * to enable I/O and memory. Wake up the device if it was suspended.
741 * Beware, this function can fail.
743 * Note we don't actually enable the device many times if we call
744 * this function repeatedly (we just increment the count).
746 int pci_enable_device(struct pci_dev *dev)
748 return pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
752 * Managed PCI resources. This manages device on/off, intx/msi/msix
753 * on/off and BAR regions. pci_dev itself records msi/msix status, so
754 * there's no need to track it separately. pci_devres is initialized
755 * when a device is enabled using managed PCI device enable interface.
757 struct pci_devres {
758 unsigned int enabled:1;
759 unsigned int pinned:1;
760 unsigned int orig_intx:1;
761 unsigned int restore_intx:1;
762 u32 region_mask;
765 static void pcim_release(struct device *gendev, void *res)
767 struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
768 struct pci_devres *this = res;
769 int i;
771 if (dev->msi_enabled)
772 pci_disable_msi(dev);
773 if (dev->msix_enabled)
774 pci_disable_msix(dev);
776 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
777 if (this->region_mask & (1 << i))
778 pci_release_region(dev, i);
780 if (this->restore_intx)
781 pci_intx(dev, this->orig_intx);
783 if (this->enabled && !this->pinned)
784 pci_disable_device(dev);
787 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
789 struct pci_devres *dr, *new_dr;
791 dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
792 if (dr)
793 return dr;
795 new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
796 if (!new_dr)
797 return NULL;
798 return devres_get(&pdev->dev, new_dr, NULL, NULL);
801 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
803 if (pci_is_managed(pdev))
804 return devres_find(&pdev->dev, pcim_release, NULL, NULL);
805 return NULL;
809 * pcim_enable_device - Managed pci_enable_device()
810 * @pdev: PCI device to be initialized
812 * Managed pci_enable_device().
814 int pcim_enable_device(struct pci_dev *pdev)
816 struct pci_devres *dr;
817 int rc;
819 dr = get_pci_dr(pdev);
820 if (unlikely(!dr))
821 return -ENOMEM;
822 WARN_ON(!!dr->enabled);
824 rc = pci_enable_device(pdev);
825 if (!rc) {
826 pdev->is_managed = 1;
827 dr->enabled = 1;
829 return rc;
833 * pcim_pin_device - Pin managed PCI device
834 * @pdev: PCI device to pin
836 * Pin managed PCI device @pdev. Pinned device won't be disabled on
837 * driver detach. @pdev must have been enabled with
838 * pcim_enable_device().
840 void pcim_pin_device(struct pci_dev *pdev)
842 struct pci_devres *dr;
844 dr = find_pci_dr(pdev);
845 WARN_ON(!dr || !dr->enabled);
846 if (dr)
847 dr->pinned = 1;
851 * pcibios_disable_device - disable arch specific PCI resources for device dev
852 * @dev: the PCI device to disable
854 * Disables architecture specific PCI resources for the device. This
855 * is the default implementation. Architecture implementations can
856 * override this.
858 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
861 * pci_disable_device - Disable PCI device after use
862 * @dev: PCI device to be disabled
864 * Signal to the system that the PCI device is not in use by the system
865 * anymore. This only involves disabling PCI bus-mastering, if active.
867 * Note we don't actually disable the device until all callers of
868 * pci_device_enable() have called pci_device_disable().
870 void
871 pci_disable_device(struct pci_dev *dev)
873 struct pci_devres *dr;
874 u16 pci_command;
876 dr = find_pci_dr(dev);
877 if (dr)
878 dr->enabled = 0;
880 if (atomic_sub_return(1, &dev->enable_cnt) != 0)
881 return;
883 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
884 if (pci_command & PCI_COMMAND_MASTER) {
885 pci_command &= ~PCI_COMMAND_MASTER;
886 pci_write_config_word(dev, PCI_COMMAND, pci_command);
888 dev->is_busmaster = 0;
890 pcibios_disable_device(dev);
894 * pcibios_set_pcie_reset_state - set reset state for device dev
895 * @dev: the PCI-E device reset
896 * @state: Reset state to enter into
899 * Sets the PCI-E reset state for the device. This is the default
900 * implementation. Architecture implementations can override this.
902 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
903 enum pcie_reset_state state)
905 return -EINVAL;
909 * pci_set_pcie_reset_state - set reset state for device dev
910 * @dev: the PCI-E device reset
911 * @state: Reset state to enter into
914 * Sets the PCI reset state for the device.
916 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
918 return pcibios_set_pcie_reset_state(dev, state);
922 * pci_enable_wake - enable PCI device as wakeup event source
923 * @dev: PCI device affected
924 * @state: PCI state from which device will issue wakeup events
925 * @enable: True to enable event generation; false to disable
927 * This enables the device as a wakeup event source, or disables it.
928 * When such events involves platform-specific hooks, those hooks are
929 * called automatically by this routine.
931 * Devices with legacy power management (no standard PCI PM capabilities)
932 * always require such platform hooks. Depending on the platform, devices
933 * supporting the standard PCI PME# signal may require such platform hooks;
934 * they always update bits in config space to allow PME# generation.
936 * -EIO is returned if the device can't ever be a wakeup event source.
937 * -EINVAL is returned if the device can't generate wakeup events from
938 * the specified PCI state. Returns zero if the operation is successful.
940 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
942 int pm;
943 int status;
944 u16 value;
946 /* Note that drivers should verify device_may_wakeup(&dev->dev)
947 * before calling this function. Platform code should report
948 * errors when drivers try to enable wakeup on devices that
949 * can't issue wakeups, or on which wakeups were disabled by
950 * userspace updating the /sys/devices.../power/wakeup file.
953 status = call_platform_enable_wakeup(&dev->dev, enable);
955 /* find PCI PM capability in list */
956 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
958 /* If device doesn't support PM Capabilities, but caller wants to
959 * disable wake events, it's a NOP. Otherwise fail unless the
960 * platform hooks handled this legacy device already.
962 if (!pm)
963 return enable ? status : 0;
965 /* Check device's ability to generate PME# */
966 pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
968 value &= PCI_PM_CAP_PME_MASK;
969 value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */
971 /* Check if it can generate PME# from requested state. */
972 if (!value || !(value & (1 << state))) {
973 /* if it can't, revert what the platform hook changed,
974 * always reporting the base "EINVAL, can't PME#" error
976 if (enable)
977 call_platform_enable_wakeup(&dev->dev, 0);
978 return enable ? -EINVAL : 0;
981 pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
983 /* Clear PME_Status by writing 1 to it and enable PME# */
984 value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
986 if (!enable)
987 value &= ~PCI_PM_CTRL_PME_ENABLE;
989 pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
991 return 0;
995 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
997 u8 pin;
999 pin = dev->pin;
1000 if (!pin)
1001 return -1;
1002 pin--;
1003 while (dev->bus->self) {
1004 pin = (pin + PCI_SLOT(dev->devfn)) % 4;
1005 dev = dev->bus->self;
1007 *bridge = dev;
1008 return pin;
1012 * pci_release_region - Release a PCI bar
1013 * @pdev: PCI device whose resources were previously reserved by pci_request_region
1014 * @bar: BAR to release
1016 * Releases the PCI I/O and memory resources previously reserved by a
1017 * successful call to pci_request_region. Call this function only
1018 * after all use of the PCI regions has ceased.
1020 void pci_release_region(struct pci_dev *pdev, int bar)
1022 struct pci_devres *dr;
1024 if (pci_resource_len(pdev, bar) == 0)
1025 return;
1026 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1027 release_region(pci_resource_start(pdev, bar),
1028 pci_resource_len(pdev, bar));
1029 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1030 release_mem_region(pci_resource_start(pdev, bar),
1031 pci_resource_len(pdev, bar));
1033 dr = find_pci_dr(pdev);
1034 if (dr)
1035 dr->region_mask &= ~(1 << bar);
1039 * pci_request_region - Reserved PCI I/O and memory resource
1040 * @pdev: PCI device whose resources are to be reserved
1041 * @bar: BAR to be reserved
1042 * @res_name: Name to be associated with resource.
1044 * Mark the PCI region associated with PCI device @pdev BR @bar as
1045 * being reserved by owner @res_name. Do not access any
1046 * address inside the PCI regions unless this call returns
1047 * successfully.
1049 * Returns 0 on success, or %EBUSY on error. A warning
1050 * message is also printed on failure.
1052 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1054 struct pci_devres *dr;
1056 if (pci_resource_len(pdev, bar) == 0)
1057 return 0;
1059 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1060 if (!request_region(pci_resource_start(pdev, bar),
1061 pci_resource_len(pdev, bar), res_name))
1062 goto err_out;
1064 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1065 if (!request_mem_region(pci_resource_start(pdev, bar),
1066 pci_resource_len(pdev, bar), res_name))
1067 goto err_out;
1070 dr = find_pci_dr(pdev);
1071 if (dr)
1072 dr->region_mask |= 1 << bar;
1074 return 0;
1076 err_out:
1077 printk (KERN_WARNING "PCI: Unable to reserve %s region #%d:%llx@%llx "
1078 "for device %s\n",
1079 pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
1080 bar + 1, /* PCI BAR # */
1081 (unsigned long long)pci_resource_len(pdev, bar),
1082 (unsigned long long)pci_resource_start(pdev, bar),
1083 pci_name(pdev));
1084 return -EBUSY;
1088 * pci_release_selected_regions - Release selected PCI I/O and memory resources
1089 * @pdev: PCI device whose resources were previously reserved
1090 * @bars: Bitmask of BARs to be released
1092 * Release selected PCI I/O and memory resources previously reserved.
1093 * Call this function only after all use of the PCI regions has ceased.
1095 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1097 int i;
1099 for (i = 0; i < 6; i++)
1100 if (bars & (1 << i))
1101 pci_release_region(pdev, i);
1105 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
1106 * @pdev: PCI device whose resources are to be reserved
1107 * @bars: Bitmask of BARs to be requested
1108 * @res_name: Name to be associated with resource
1110 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
1111 const char *res_name)
1113 int i;
1115 for (i = 0; i < 6; i++)
1116 if (bars & (1 << i))
1117 if(pci_request_region(pdev, i, res_name))
1118 goto err_out;
1119 return 0;
1121 err_out:
1122 while(--i >= 0)
1123 if (bars & (1 << i))
1124 pci_release_region(pdev, i);
1126 return -EBUSY;
1130 * pci_release_regions - Release reserved PCI I/O and memory resources
1131 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
1133 * Releases all PCI I/O and memory resources previously reserved by a
1134 * successful call to pci_request_regions. Call this function only
1135 * after all use of the PCI regions has ceased.
1138 void pci_release_regions(struct pci_dev *pdev)
1140 pci_release_selected_regions(pdev, (1 << 6) - 1);
1144 * pci_request_regions - Reserved PCI I/O and memory resources
1145 * @pdev: PCI device whose resources are to be reserved
1146 * @res_name: Name to be associated with resource.
1148 * Mark all PCI regions associated with PCI device @pdev as
1149 * being reserved by owner @res_name. Do not access any
1150 * address inside the PCI regions unless this call returns
1151 * successfully.
1153 * Returns 0 on success, or %EBUSY on error. A warning
1154 * message is also printed on failure.
1156 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
1158 return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
1162 * pci_set_master - enables bus-mastering for device dev
1163 * @dev: the PCI device to enable
1165 * Enables bus-mastering on the device and calls pcibios_set_master()
1166 * to do the needed arch specific settings.
1168 void
1169 pci_set_master(struct pci_dev *dev)
1171 u16 cmd;
1173 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1174 if (! (cmd & PCI_COMMAND_MASTER)) {
1175 pr_debug("PCI: Enabling bus mastering for device %s\n", pci_name(dev));
1176 cmd |= PCI_COMMAND_MASTER;
1177 pci_write_config_word(dev, PCI_COMMAND, cmd);
1179 dev->is_busmaster = 1;
1180 pcibios_set_master(dev);
1183 #ifdef PCI_DISABLE_MWI
1184 int pci_set_mwi(struct pci_dev *dev)
1186 return 0;
1189 void pci_clear_mwi(struct pci_dev *dev)
1193 #else
1195 #ifndef PCI_CACHE_LINE_BYTES
1196 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
1197 #endif
1199 /* This can be overridden by arch code. */
1200 /* Don't forget this is measured in 32-bit words, not bytes */
1201 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
1204 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1205 * @dev: the PCI device for which MWI is to be enabled
1207 * Helper function for pci_set_mwi.
1208 * Originally copied from drivers/net/acenic.c.
1209 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1211 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1213 static int
1214 pci_set_cacheline_size(struct pci_dev *dev)
1216 u8 cacheline_size;
1218 if (!pci_cache_line_size)
1219 return -EINVAL; /* The system doesn't support MWI. */
1221 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1222 equal to or multiple of the right value. */
1223 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1224 if (cacheline_size >= pci_cache_line_size &&
1225 (cacheline_size % pci_cache_line_size) == 0)
1226 return 0;
1228 /* Write the correct value. */
1229 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1230 /* Read it back. */
1231 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1232 if (cacheline_size == pci_cache_line_size)
1233 return 0;
1235 printk(KERN_DEBUG "PCI: cache line size of %d is not supported "
1236 "by device %s\n", pci_cache_line_size << 2, pci_name(dev));
1238 return -EINVAL;
1242 * pci_set_mwi - enables memory-write-invalidate PCI transaction
1243 * @dev: the PCI device for which MWI is enabled
1245 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND,
1246 * and then calls @pcibios_set_mwi to do the needed arch specific
1247 * operations or a generic mwi-prep function.
1249 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1252 pci_set_mwi(struct pci_dev *dev)
1254 int rc;
1255 u16 cmd;
1257 rc = pci_set_cacheline_size(dev);
1258 if (rc)
1259 return rc;
1261 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1262 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1263 pr_debug("PCI: Enabling Mem-Wr-Inval for device %s\n", pci_name(dev));
1264 cmd |= PCI_COMMAND_INVALIDATE;
1265 pci_write_config_word(dev, PCI_COMMAND, cmd);
1268 return 0;
1272 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1273 * @dev: the PCI device to disable
1275 * Disables PCI Memory-Write-Invalidate transaction on the device
1277 void
1278 pci_clear_mwi(struct pci_dev *dev)
1280 u16 cmd;
1282 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1283 if (cmd & PCI_COMMAND_INVALIDATE) {
1284 cmd &= ~PCI_COMMAND_INVALIDATE;
1285 pci_write_config_word(dev, PCI_COMMAND, cmd);
1288 #endif /* ! PCI_DISABLE_MWI */
1291 * pci_intx - enables/disables PCI INTx for device dev
1292 * @pdev: the PCI device to operate on
1293 * @enable: boolean: whether to enable or disable PCI INTx
1295 * Enables/disables PCI INTx for device dev
1297 void
1298 pci_intx(struct pci_dev *pdev, int enable)
1300 u16 pci_command, new;
1302 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1304 if (enable) {
1305 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1306 } else {
1307 new = pci_command | PCI_COMMAND_INTX_DISABLE;
1310 if (new != pci_command) {
1311 struct pci_devres *dr;
1313 pci_write_config_word(pdev, PCI_COMMAND, new);
1315 dr = find_pci_dr(pdev);
1316 if (dr && !dr->restore_intx) {
1317 dr->restore_intx = 1;
1318 dr->orig_intx = !enable;
1324 * pci_msi_off - disables any msi or msix capabilities
1325 * @dev: the PCI device to operate on
1327 * If you want to use msi see pci_enable_msi and friends.
1328 * This is a lower level primitive that allows us to disable
1329 * msi operation at the device level.
1331 void pci_msi_off(struct pci_dev *dev)
1333 int pos;
1334 u16 control;
1336 pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
1337 if (pos) {
1338 pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
1339 control &= ~PCI_MSI_FLAGS_ENABLE;
1340 pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
1342 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1343 if (pos) {
1344 pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
1345 control &= ~PCI_MSIX_FLAGS_ENABLE;
1346 pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
1350 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
1352 * These can be overridden by arch-specific implementations
1355 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
1357 if (!pci_dma_supported(dev, mask))
1358 return -EIO;
1360 dev->dma_mask = mask;
1362 return 0;
1366 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
1368 if (!pci_dma_supported(dev, mask))
1369 return -EIO;
1371 dev->dev.coherent_dma_mask = mask;
1373 return 0;
1375 #endif
1378 * pci_select_bars - Make BAR mask from the type of resource
1379 * @dev: the PCI device for which BAR mask is made
1380 * @flags: resource type mask to be selected
1382 * This helper routine makes bar mask from the type of resource.
1384 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
1386 int i, bars = 0;
1387 for (i = 0; i < PCI_NUM_RESOURCES; i++)
1388 if (pci_resource_flags(dev, i) & flags)
1389 bars |= (1 << i);
1390 return bars;
1393 static int __devinit pci_init(void)
1395 struct pci_dev *dev = NULL;
1397 while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
1398 pci_fixup_device(pci_fixup_final, dev);
1400 return 0;
1403 static int __devinit pci_setup(char *str)
1405 while (str) {
1406 char *k = strchr(str, ',');
1407 if (k)
1408 *k++ = 0;
1409 if (*str && (str = pcibios_setup(str)) && *str) {
1410 if (!strcmp(str, "nomsi")) {
1411 pci_no_msi();
1412 } else if (!strncmp(str, "cbiosize=", 9)) {
1413 pci_cardbus_io_size = memparse(str + 9, &str);
1414 } else if (!strncmp(str, "cbmemsize=", 10)) {
1415 pci_cardbus_mem_size = memparse(str + 10, &str);
1416 } else {
1417 printk(KERN_ERR "PCI: Unknown option `%s'\n",
1418 str);
1421 str = k;
1423 return 0;
1425 early_param("pci", pci_setup);
1427 device_initcall(pci_init);
1429 EXPORT_SYMBOL_GPL(pci_restore_bars);
1430 EXPORT_SYMBOL(pci_enable_device_bars);
1431 EXPORT_SYMBOL(pci_enable_device);
1432 EXPORT_SYMBOL(pcim_enable_device);
1433 EXPORT_SYMBOL(pcim_pin_device);
1434 EXPORT_SYMBOL(pci_disable_device);
1435 EXPORT_SYMBOL(pci_find_capability);
1436 EXPORT_SYMBOL(pci_bus_find_capability);
1437 EXPORT_SYMBOL(pci_release_regions);
1438 EXPORT_SYMBOL(pci_request_regions);
1439 EXPORT_SYMBOL(pci_release_region);
1440 EXPORT_SYMBOL(pci_request_region);
1441 EXPORT_SYMBOL(pci_release_selected_regions);
1442 EXPORT_SYMBOL(pci_request_selected_regions);
1443 EXPORT_SYMBOL(pci_set_master);
1444 EXPORT_SYMBOL(pci_set_mwi);
1445 EXPORT_SYMBOL(pci_clear_mwi);
1446 EXPORT_SYMBOL_GPL(pci_intx);
1447 EXPORT_SYMBOL(pci_set_dma_mask);
1448 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
1449 EXPORT_SYMBOL(pci_assign_resource);
1450 EXPORT_SYMBOL(pci_find_parent_resource);
1451 EXPORT_SYMBOL(pci_select_bars);
1453 EXPORT_SYMBOL(pci_set_power_state);
1454 EXPORT_SYMBOL(pci_save_state);
1455 EXPORT_SYMBOL(pci_restore_state);
1456 EXPORT_SYMBOL(pci_enable_wake);
1457 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);