PCI : Move pci_fixup_device and is_enabled (originally intended change)
[linux-2.6/cjktty.git] / drivers / pci / pci.c
blob212acd2e1a842c16c82d937db66e2768886cd686
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/module.h>
17 #include <linux/spinlock.h>
18 #include <linux/string.h>
19 #include <asm/dma.h> /* isa_dma_bridge_buggy */
20 #include "pci.h"
22 unsigned int pci_pm_d3_delay = 10;
24 /**
25 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
26 * @bus: pointer to PCI bus structure to search
28 * Given a PCI bus, returns the highest PCI bus number present in the set
29 * including the given PCI bus and its list of child PCI buses.
31 unsigned char __devinit
32 pci_bus_max_busnr(struct pci_bus* bus)
34 struct list_head *tmp;
35 unsigned char max, n;
37 max = bus->subordinate;
38 list_for_each(tmp, &bus->children) {
39 n = pci_bus_max_busnr(pci_bus_b(tmp));
40 if(n > max)
41 max = n;
43 return max;
45 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
47 #if 0
48 /**
49 * pci_max_busnr - returns maximum PCI bus number
51 * Returns the highest PCI bus number present in the system global list of
52 * PCI buses.
54 unsigned char __devinit
55 pci_max_busnr(void)
57 struct pci_bus *bus = NULL;
58 unsigned char max, n;
60 max = 0;
61 while ((bus = pci_find_next_bus(bus)) != NULL) {
62 n = pci_bus_max_busnr(bus);
63 if(n > max)
64 max = n;
66 return max;
69 #endif /* 0 */
71 #define PCI_FIND_CAP_TTL 48
73 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
74 u8 pos, int cap, int *ttl)
76 u8 id;
78 while ((*ttl)--) {
79 pci_bus_read_config_byte(bus, devfn, pos, &pos);
80 if (pos < 0x40)
81 break;
82 pos &= ~3;
83 pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
84 &id);
85 if (id == 0xff)
86 break;
87 if (id == cap)
88 return pos;
89 pos += PCI_CAP_LIST_NEXT;
91 return 0;
94 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
95 u8 pos, int cap)
97 int ttl = PCI_FIND_CAP_TTL;
99 return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
102 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
104 return __pci_find_next_cap(dev->bus, dev->devfn,
105 pos + PCI_CAP_LIST_NEXT, cap);
107 EXPORT_SYMBOL_GPL(pci_find_next_capability);
109 static int __pci_bus_find_cap_start(struct pci_bus *bus,
110 unsigned int devfn, u8 hdr_type)
112 u16 status;
114 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
115 if (!(status & PCI_STATUS_CAP_LIST))
116 return 0;
118 switch (hdr_type) {
119 case PCI_HEADER_TYPE_NORMAL:
120 case PCI_HEADER_TYPE_BRIDGE:
121 return PCI_CAPABILITY_LIST;
122 case PCI_HEADER_TYPE_CARDBUS:
123 return PCI_CB_CAPABILITY_LIST;
124 default:
125 return 0;
128 return 0;
132 * pci_find_capability - query for devices' capabilities
133 * @dev: PCI device to query
134 * @cap: capability code
136 * Tell if a device supports a given PCI capability.
137 * Returns the address of the requested capability structure within the
138 * device's PCI configuration space or 0 in case the device does not
139 * support it. Possible values for @cap:
141 * %PCI_CAP_ID_PM Power Management
142 * %PCI_CAP_ID_AGP Accelerated Graphics Port
143 * %PCI_CAP_ID_VPD Vital Product Data
144 * %PCI_CAP_ID_SLOTID Slot Identification
145 * %PCI_CAP_ID_MSI Message Signalled Interrupts
146 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
147 * %PCI_CAP_ID_PCIX PCI-X
148 * %PCI_CAP_ID_EXP PCI Express
150 int pci_find_capability(struct pci_dev *dev, int cap)
152 int pos;
154 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
155 if (pos)
156 pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
158 return pos;
162 * pci_bus_find_capability - query for devices' capabilities
163 * @bus: the PCI bus to query
164 * @devfn: PCI device to query
165 * @cap: capability code
167 * Like pci_find_capability() but works for pci devices that do not have a
168 * pci_dev structure set up yet.
170 * Returns the address of the requested capability structure within the
171 * device's PCI configuration space or 0 in case the device does not
172 * support it.
174 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
176 int pos;
177 u8 hdr_type;
179 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
181 pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
182 if (pos)
183 pos = __pci_find_next_cap(bus, devfn, pos, cap);
185 return pos;
189 * pci_find_ext_capability - Find an extended capability
190 * @dev: PCI device to query
191 * @cap: capability code
193 * Returns the address of the requested extended capability structure
194 * within the device's PCI configuration space or 0 if the device does
195 * not support it. Possible values for @cap:
197 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
198 * %PCI_EXT_CAP_ID_VC Virtual Channel
199 * %PCI_EXT_CAP_ID_DSN Device Serial Number
200 * %PCI_EXT_CAP_ID_PWR Power Budgeting
202 int pci_find_ext_capability(struct pci_dev *dev, int cap)
204 u32 header;
205 int ttl = 480; /* 3840 bytes, minimum 8 bytes per capability */
206 int pos = 0x100;
208 if (dev->cfg_size <= 256)
209 return 0;
211 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
212 return 0;
215 * If we have no capabilities, this is indicated by cap ID,
216 * cap version and next pointer all being 0.
218 if (header == 0)
219 return 0;
221 while (ttl-- > 0) {
222 if (PCI_EXT_CAP_ID(header) == cap)
223 return pos;
225 pos = PCI_EXT_CAP_NEXT(header);
226 if (pos < 0x100)
227 break;
229 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
230 break;
233 return 0;
235 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
237 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
239 int rc, ttl = PCI_FIND_CAP_TTL;
240 u8 cap, mask;
242 if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
243 mask = HT_3BIT_CAP_MASK;
244 else
245 mask = HT_5BIT_CAP_MASK;
247 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
248 PCI_CAP_ID_HT, &ttl);
249 while (pos) {
250 rc = pci_read_config_byte(dev, pos + 3, &cap);
251 if (rc != PCIBIOS_SUCCESSFUL)
252 return 0;
254 if ((cap & mask) == ht_cap)
255 return pos;
257 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
258 pos + PCI_CAP_LIST_NEXT,
259 PCI_CAP_ID_HT, &ttl);
262 return 0;
265 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
266 * @dev: PCI device to query
267 * @pos: Position from which to continue searching
268 * @ht_cap: Hypertransport capability code
270 * To be used in conjunction with pci_find_ht_capability() to search for
271 * all capabilities matching @ht_cap. @pos should always be a value returned
272 * from pci_find_ht_capability().
274 * NB. To be 100% safe against broken PCI devices, the caller should take
275 * steps to avoid an infinite loop.
277 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
279 return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
281 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
284 * pci_find_ht_capability - query a device's Hypertransport capabilities
285 * @dev: PCI device to query
286 * @ht_cap: Hypertransport capability code
288 * Tell if a device supports a given Hypertransport capability.
289 * Returns an address within the device's PCI configuration space
290 * or 0 in case the device does not support the request capability.
291 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
292 * which has a Hypertransport capability matching @ht_cap.
294 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
296 int pos;
298 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
299 if (pos)
300 pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
302 return pos;
304 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
307 * pci_find_parent_resource - return resource region of parent bus of given region
308 * @dev: PCI device structure contains resources to be searched
309 * @res: child resource record for which parent is sought
311 * For given resource region of given device, return the resource
312 * region of parent bus the given region is contained in or where
313 * it should be allocated from.
315 struct resource *
316 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
318 const struct pci_bus *bus = dev->bus;
319 int i;
320 struct resource *best = NULL;
322 for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
323 struct resource *r = bus->resource[i];
324 if (!r)
325 continue;
326 if (res->start && !(res->start >= r->start && res->end <= r->end))
327 continue; /* Not contained */
328 if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
329 continue; /* Wrong type */
330 if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
331 return r; /* Exact match */
332 if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
333 best = r; /* Approximating prefetchable by non-prefetchable */
335 return best;
339 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
340 * @dev: PCI device to have its BARs restored
342 * Restore the BAR values for a given device, so as to make it
343 * accessible by its driver.
345 void
346 pci_restore_bars(struct pci_dev *dev)
348 int i, numres;
350 switch (dev->hdr_type) {
351 case PCI_HEADER_TYPE_NORMAL:
352 numres = 6;
353 break;
354 case PCI_HEADER_TYPE_BRIDGE:
355 numres = 2;
356 break;
357 case PCI_HEADER_TYPE_CARDBUS:
358 numres = 1;
359 break;
360 default:
361 /* Should never get here, but just in case... */
362 return;
365 for (i = 0; i < numres; i ++)
366 pci_update_resource(dev, &dev->resource[i], i);
369 int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t t);
372 * pci_set_power_state - Set the power state of a PCI device
373 * @dev: PCI device to be suspended
374 * @state: PCI power state (D0, D1, D2, D3hot, D3cold) we're entering
376 * Transition a device to a new power state, using the Power Management
377 * Capabilities in the device's config space.
379 * RETURN VALUE:
380 * -EINVAL if trying to enter a lower state than we're already in.
381 * 0 if we're already in the requested state.
382 * -EIO if device does not support PCI PM.
383 * 0 if we can successfully change the power state.
386 pci_set_power_state(struct pci_dev *dev, pci_power_t state)
388 int pm, need_restore = 0;
389 u16 pmcsr, pmc;
391 /* bound the state we're entering */
392 if (state > PCI_D3hot)
393 state = PCI_D3hot;
395 /* Validate current state:
396 * Can enter D0 from any state, but if we can only go deeper
397 * to sleep if we're already in a low power state
399 if (state != PCI_D0 && dev->current_state > state) {
400 printk(KERN_ERR "%s(): %s: state=%d, current state=%d\n",
401 __FUNCTION__, pci_name(dev), state, dev->current_state);
402 return -EINVAL;
403 } else if (dev->current_state == state)
404 return 0; /* we're already there */
407 * If the device or the parent bridge can't support PCI PM, ignore
408 * the request if we're doing anything besides putting it into D0
409 * (which would only happen on boot).
411 if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
412 return 0;
414 /* find PCI PM capability in list */
415 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
417 /* abort if the device doesn't support PM capabilities */
418 if (!pm)
419 return -EIO;
421 pci_read_config_word(dev,pm + PCI_PM_PMC,&pmc);
422 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
423 printk(KERN_DEBUG
424 "PCI: %s has unsupported PM cap regs version (%u)\n",
425 pci_name(dev), pmc & PCI_PM_CAP_VER_MASK);
426 return -EIO;
429 /* check if this device supports the desired state */
430 if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
431 return -EIO;
432 else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2))
433 return -EIO;
435 pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
437 /* If we're (effectively) in D3, force entire word to 0.
438 * This doesn't affect PME_Status, disables PME_En, and
439 * sets PowerState to 0.
441 switch (dev->current_state) {
442 case PCI_D0:
443 case PCI_D1:
444 case PCI_D2:
445 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
446 pmcsr |= state;
447 break;
448 case PCI_UNKNOWN: /* Boot-up */
449 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
450 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
451 need_restore = 1;
452 /* Fall-through: force to D0 */
453 default:
454 pmcsr = 0;
455 break;
458 /* enter specified state */
459 pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
461 /* Mandatory power management transition delays */
462 /* see PCI PM 1.1 5.6.1 table 18 */
463 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
464 msleep(pci_pm_d3_delay);
465 else if (state == PCI_D2 || dev->current_state == PCI_D2)
466 udelay(200);
469 * Give firmware a chance to be called, such as ACPI _PRx, _PSx
470 * Firmware method after native method ?
472 if (platform_pci_set_power_state)
473 platform_pci_set_power_state(dev, state);
475 dev->current_state = state;
477 /* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
478 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
479 * from D3hot to D0 _may_ perform an internal reset, thereby
480 * going to "D0 Uninitialized" rather than "D0 Initialized".
481 * For example, at least some versions of the 3c905B and the
482 * 3c556B exhibit this behaviour.
484 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
485 * devices in a D3hot state at boot. Consequently, we need to
486 * restore at least the BARs so that the device will be
487 * accessible to its driver.
489 if (need_restore)
490 pci_restore_bars(dev);
492 return 0;
495 int (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
498 * pci_choose_state - Choose the power state of a PCI device
499 * @dev: PCI device to be suspended
500 * @state: target sleep state for the whole system. This is the value
501 * that is passed to suspend() function.
503 * Returns PCI power state suitable for given device and given system
504 * message.
507 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
509 int ret;
511 if (!pci_find_capability(dev, PCI_CAP_ID_PM))
512 return PCI_D0;
514 if (platform_pci_choose_state) {
515 ret = platform_pci_choose_state(dev, state);
516 if (ret >= 0)
517 state.event = ret;
520 switch (state.event) {
521 case PM_EVENT_ON:
522 return PCI_D0;
523 case PM_EVENT_FREEZE:
524 case PM_EVENT_PRETHAW:
525 /* REVISIT both freeze and pre-thaw "should" use D0 */
526 case PM_EVENT_SUSPEND:
527 return PCI_D3hot;
528 default:
529 printk("Unrecognized suspend event %d\n", state.event);
530 BUG();
532 return PCI_D0;
535 EXPORT_SYMBOL(pci_choose_state);
537 static int pci_save_pcie_state(struct pci_dev *dev)
539 int pos, i = 0;
540 struct pci_cap_saved_state *save_state;
541 u16 *cap;
543 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
544 if (pos <= 0)
545 return 0;
547 save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);
548 if (!save_state) {
549 dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
550 return -ENOMEM;
552 cap = (u16 *)&save_state->data[0];
554 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
555 pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
556 pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
557 pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
558 pci_add_saved_cap(dev, save_state);
559 return 0;
562 static void pci_restore_pcie_state(struct pci_dev *dev)
564 int i = 0, pos;
565 struct pci_cap_saved_state *save_state;
566 u16 *cap;
568 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
569 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
570 if (!save_state || pos <= 0)
571 return;
572 cap = (u16 *)&save_state->data[0];
574 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
575 pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
576 pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
577 pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
578 pci_remove_saved_cap(save_state);
579 kfree(save_state);
583 static int pci_save_pcix_state(struct pci_dev *dev)
585 int pos, i = 0;
586 struct pci_cap_saved_state *save_state;
587 u16 *cap;
589 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
590 if (pos <= 0)
591 return 0;
593 save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);
594 if (!save_state) {
595 dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
596 return -ENOMEM;
598 cap = (u16 *)&save_state->data[0];
600 pci_read_config_word(dev, pos + PCI_X_CMD, &cap[i++]);
601 pci_add_saved_cap(dev, save_state);
602 return 0;
605 static void pci_restore_pcix_state(struct pci_dev *dev)
607 int i = 0, pos;
608 struct pci_cap_saved_state *save_state;
609 u16 *cap;
611 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
612 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
613 if (!save_state || pos <= 0)
614 return;
615 cap = (u16 *)&save_state->data[0];
617 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
618 pci_remove_saved_cap(save_state);
619 kfree(save_state);
624 * pci_save_state - save the PCI configuration space of a device before suspending
625 * @dev: - PCI device that we're dealing with
628 pci_save_state(struct pci_dev *dev)
630 int i;
631 /* XXX: 100% dword access ok here? */
632 for (i = 0; i < 16; i++)
633 pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
634 if ((i = pci_save_msi_state(dev)) != 0)
635 return i;
636 if ((i = pci_save_msix_state(dev)) != 0)
637 return i;
638 if ((i = pci_save_pcie_state(dev)) != 0)
639 return i;
640 if ((i = pci_save_pcix_state(dev)) != 0)
641 return i;
642 return 0;
645 /**
646 * pci_restore_state - Restore the saved state of a PCI device
647 * @dev: - PCI device that we're dealing with
649 int
650 pci_restore_state(struct pci_dev *dev)
652 int i;
653 int val;
655 /* PCI Express register must be restored first */
656 pci_restore_pcie_state(dev);
659 * The Base Address register should be programmed before the command
660 * register(s)
662 for (i = 15; i >= 0; i--) {
663 pci_read_config_dword(dev, i * 4, &val);
664 if (val != dev->saved_config_space[i]) {
665 printk(KERN_DEBUG "PM: Writing back config space on "
666 "device %s at offset %x (was %x, writing %x)\n",
667 pci_name(dev), i,
668 val, (int)dev->saved_config_space[i]);
669 pci_write_config_dword(dev,i * 4,
670 dev->saved_config_space[i]);
673 pci_restore_pcix_state(dev);
674 pci_restore_msi_state(dev);
675 pci_restore_msix_state(dev);
676 return 0;
680 * pci_enable_device_bars - Initialize some of a device for use
681 * @dev: PCI device to be initialized
682 * @bars: bitmask of BAR's that must be configured
684 * Initialize device before it's used by a driver. Ask low-level code
685 * to enable selected I/O and memory resources. Wake up the device if it
686 * was suspended. Beware, this function can fail.
689 pci_enable_device_bars(struct pci_dev *dev, int bars)
691 int err;
693 if (atomic_add_return(1, &dev->enable_cnt) > 1)
694 return 0; /* already enabled */
696 err = pci_set_power_state(dev, PCI_D0);
697 if (err < 0 && err != -EIO)
698 goto err_out;
699 err = pcibios_enable_device(dev, bars);
700 if (err < 0)
701 goto err_out;
702 pci_fixup_device(pci_fixup_enable, dev);
704 err_out:
705 atomic_dec(&dev->enable_cnt);
706 return err;
710 * pci_enable_device - Initialize device before it's used by a driver.
711 * @dev: PCI device to be initialized
713 * Initialize device before it's used by a driver. Ask low-level code
714 * to enable I/O and memory. Wake up the device if it was suspended.
715 * Beware, this function can fail.
717 * Note we don't actually enable the device many times if we call
718 * this function repeatedly (we just increment the count).
720 int pci_enable_device(struct pci_dev *dev)
722 return pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
726 * pcibios_disable_device - disable arch specific PCI resources for device dev
727 * @dev: the PCI device to disable
729 * Disables architecture specific PCI resources for the device. This
730 * is the default implementation. Architecture implementations can
731 * override this.
733 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
736 * pci_disable_device - Disable PCI device after use
737 * @dev: PCI device to be disabled
739 * Signal to the system that the PCI device is not in use by the system
740 * anymore. This only involves disabling PCI bus-mastering, if active.
742 * Note we don't actually disable the device until all callers of
743 * pci_device_enable() have called pci_device_disable().
745 void
746 pci_disable_device(struct pci_dev *dev)
748 u16 pci_command;
750 if (atomic_sub_return(1, &dev->enable_cnt) != 0)
751 return;
753 if (dev->msi_enabled)
754 disable_msi_mode(dev, pci_find_capability(dev, PCI_CAP_ID_MSI),
755 PCI_CAP_ID_MSI);
756 if (dev->msix_enabled)
757 disable_msi_mode(dev, pci_find_capability(dev, PCI_CAP_ID_MSI),
758 PCI_CAP_ID_MSIX);
760 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
761 if (pci_command & PCI_COMMAND_MASTER) {
762 pci_command &= ~PCI_COMMAND_MASTER;
763 pci_write_config_word(dev, PCI_COMMAND, pci_command);
765 dev->is_busmaster = 0;
767 pcibios_disable_device(dev);
771 * pci_enable_wake - enable device to generate PME# when suspended
772 * @dev: - PCI device to operate on
773 * @state: - Current state of device.
774 * @enable: - Flag to enable or disable generation
776 * Set the bits in the device's PM Capabilities to generate PME# when
777 * the system is suspended.
779 * -EIO is returned if device doesn't have PM Capabilities.
780 * -EINVAL is returned if device supports it, but can't generate wake events.
781 * 0 if operation is successful.
784 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
786 int pm;
787 u16 value;
789 /* find PCI PM capability in list */
790 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
792 /* If device doesn't support PM Capabilities, but request is to disable
793 * wake events, it's a nop; otherwise fail */
794 if (!pm)
795 return enable ? -EIO : 0;
797 /* Check device's ability to generate PME# */
798 pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
800 value &= PCI_PM_CAP_PME_MASK;
801 value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */
803 /* Check if it can generate PME# from requested state. */
804 if (!value || !(value & (1 << state)))
805 return enable ? -EINVAL : 0;
807 pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
809 /* Clear PME_Status by writing 1 to it and enable PME# */
810 value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
812 if (!enable)
813 value &= ~PCI_PM_CTRL_PME_ENABLE;
815 pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
817 return 0;
821 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
823 u8 pin;
825 pin = dev->pin;
826 if (!pin)
827 return -1;
828 pin--;
829 while (dev->bus->self) {
830 pin = (pin + PCI_SLOT(dev->devfn)) % 4;
831 dev = dev->bus->self;
833 *bridge = dev;
834 return pin;
838 * pci_release_region - Release a PCI bar
839 * @pdev: PCI device whose resources were previously reserved by pci_request_region
840 * @bar: BAR to release
842 * Releases the PCI I/O and memory resources previously reserved by a
843 * successful call to pci_request_region. Call this function only
844 * after all use of the PCI regions has ceased.
846 void pci_release_region(struct pci_dev *pdev, int bar)
848 if (pci_resource_len(pdev, bar) == 0)
849 return;
850 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
851 release_region(pci_resource_start(pdev, bar),
852 pci_resource_len(pdev, bar));
853 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
854 release_mem_region(pci_resource_start(pdev, bar),
855 pci_resource_len(pdev, bar));
859 * pci_request_region - Reserved PCI I/O and memory resource
860 * @pdev: PCI device whose resources are to be reserved
861 * @bar: BAR to be reserved
862 * @res_name: Name to be associated with resource.
864 * Mark the PCI region associated with PCI device @pdev BR @bar as
865 * being reserved by owner @res_name. Do not access any
866 * address inside the PCI regions unless this call returns
867 * successfully.
869 * Returns 0 on success, or %EBUSY on error. A warning
870 * message is also printed on failure.
872 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
874 if (pci_resource_len(pdev, bar) == 0)
875 return 0;
877 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
878 if (!request_region(pci_resource_start(pdev, bar),
879 pci_resource_len(pdev, bar), res_name))
880 goto err_out;
882 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
883 if (!request_mem_region(pci_resource_start(pdev, bar),
884 pci_resource_len(pdev, bar), res_name))
885 goto err_out;
888 return 0;
890 err_out:
891 printk (KERN_WARNING "PCI: Unable to reserve %s region #%d:%llx@%llx "
892 "for device %s\n",
893 pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
894 bar + 1, /* PCI BAR # */
895 (unsigned long long)pci_resource_len(pdev, bar),
896 (unsigned long long)pci_resource_start(pdev, bar),
897 pci_name(pdev));
898 return -EBUSY;
903 * pci_release_regions - Release reserved PCI I/O and memory resources
904 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
906 * Releases all PCI I/O and memory resources previously reserved by a
907 * successful call to pci_request_regions. Call this function only
908 * after all use of the PCI regions has ceased.
911 void pci_release_regions(struct pci_dev *pdev)
913 int i;
915 for (i = 0; i < 6; i++)
916 pci_release_region(pdev, i);
920 * pci_request_regions - Reserved PCI I/O and memory resources
921 * @pdev: PCI device whose resources are to be reserved
922 * @res_name: Name to be associated with resource.
924 * Mark all PCI regions associated with PCI device @pdev as
925 * being reserved by owner @res_name. Do not access any
926 * address inside the PCI regions unless this call returns
927 * successfully.
929 * Returns 0 on success, or %EBUSY on error. A warning
930 * message is also printed on failure.
932 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
934 int i;
936 for (i = 0; i < 6; i++)
937 if(pci_request_region(pdev, i, res_name))
938 goto err_out;
939 return 0;
941 err_out:
942 while(--i >= 0)
943 pci_release_region(pdev, i);
945 return -EBUSY;
949 * pci_set_master - enables bus-mastering for device dev
950 * @dev: the PCI device to enable
952 * Enables bus-mastering on the device and calls pcibios_set_master()
953 * to do the needed arch specific settings.
955 void
956 pci_set_master(struct pci_dev *dev)
958 u16 cmd;
960 pci_read_config_word(dev, PCI_COMMAND, &cmd);
961 if (! (cmd & PCI_COMMAND_MASTER)) {
962 pr_debug("PCI: Enabling bus mastering for device %s\n", pci_name(dev));
963 cmd |= PCI_COMMAND_MASTER;
964 pci_write_config_word(dev, PCI_COMMAND, cmd);
966 dev->is_busmaster = 1;
967 pcibios_set_master(dev);
970 #ifdef PCI_DISABLE_MWI
971 int pci_set_mwi(struct pci_dev *dev)
973 return 0;
976 void pci_clear_mwi(struct pci_dev *dev)
980 #else
982 #ifndef PCI_CACHE_LINE_BYTES
983 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
984 #endif
986 /* This can be overridden by arch code. */
987 /* Don't forget this is measured in 32-bit words, not bytes */
988 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
991 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
992 * @dev: the PCI device for which MWI is to be enabled
994 * Helper function for pci_set_mwi.
995 * Originally copied from drivers/net/acenic.c.
996 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
998 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1000 static int
1001 pci_set_cacheline_size(struct pci_dev *dev)
1003 u8 cacheline_size;
1005 if (!pci_cache_line_size)
1006 return -EINVAL; /* The system doesn't support MWI. */
1008 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1009 equal to or multiple of the right value. */
1010 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1011 if (cacheline_size >= pci_cache_line_size &&
1012 (cacheline_size % pci_cache_line_size) == 0)
1013 return 0;
1015 /* Write the correct value. */
1016 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1017 /* Read it back. */
1018 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1019 if (cacheline_size == pci_cache_line_size)
1020 return 0;
1022 printk(KERN_DEBUG "PCI: cache line size of %d is not supported "
1023 "by device %s\n", pci_cache_line_size << 2, pci_name(dev));
1025 return -EINVAL;
1029 * pci_set_mwi - enables memory-write-invalidate PCI transaction
1030 * @dev: the PCI device for which MWI is enabled
1032 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND,
1033 * and then calls @pcibios_set_mwi to do the needed arch specific
1034 * operations or a generic mwi-prep function.
1036 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1039 pci_set_mwi(struct pci_dev *dev)
1041 int rc;
1042 u16 cmd;
1044 rc = pci_set_cacheline_size(dev);
1045 if (rc)
1046 return rc;
1048 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1049 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1050 pr_debug("PCI: Enabling Mem-Wr-Inval for device %s\n", pci_name(dev));
1051 cmd |= PCI_COMMAND_INVALIDATE;
1052 pci_write_config_word(dev, PCI_COMMAND, cmd);
1055 return 0;
1059 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1060 * @dev: the PCI device to disable
1062 * Disables PCI Memory-Write-Invalidate transaction on the device
1064 void
1065 pci_clear_mwi(struct pci_dev *dev)
1067 u16 cmd;
1069 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1070 if (cmd & PCI_COMMAND_INVALIDATE) {
1071 cmd &= ~PCI_COMMAND_INVALIDATE;
1072 pci_write_config_word(dev, PCI_COMMAND, cmd);
1075 #endif /* ! PCI_DISABLE_MWI */
1078 * pci_intx - enables/disables PCI INTx for device dev
1079 * @pdev: the PCI device to operate on
1080 * @enable: boolean: whether to enable or disable PCI INTx
1082 * Enables/disables PCI INTx for device dev
1084 void
1085 pci_intx(struct pci_dev *pdev, int enable)
1087 u16 pci_command, new;
1089 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1091 if (enable) {
1092 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1093 } else {
1094 new = pci_command | PCI_COMMAND_INTX_DISABLE;
1097 if (new != pci_command) {
1098 pci_write_config_word(pdev, PCI_COMMAND, new);
1102 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
1104 * These can be overridden by arch-specific implementations
1107 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
1109 if (!pci_dma_supported(dev, mask))
1110 return -EIO;
1112 dev->dma_mask = mask;
1114 return 0;
1118 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
1120 if (!pci_dma_supported(dev, mask))
1121 return -EIO;
1123 dev->dev.coherent_dma_mask = mask;
1125 return 0;
1127 #endif
1129 static int __devinit pci_init(void)
1131 struct pci_dev *dev = NULL;
1133 while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
1134 pci_fixup_device(pci_fixup_final, dev);
1136 return 0;
1139 static int __devinit pci_setup(char *str)
1141 while (str) {
1142 char *k = strchr(str, ',');
1143 if (k)
1144 *k++ = 0;
1145 if (*str && (str = pcibios_setup(str)) && *str) {
1146 if (!strcmp(str, "nomsi")) {
1147 pci_no_msi();
1148 } else {
1149 printk(KERN_ERR "PCI: Unknown option `%s'\n",
1150 str);
1153 str = k;
1155 return 0;
1157 early_param("pci", pci_setup);
1159 device_initcall(pci_init);
1161 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
1162 /* FIXME: Some boxes have multiple ISA bridges! */
1163 struct pci_dev *isa_bridge;
1164 EXPORT_SYMBOL(isa_bridge);
1165 #endif
1167 EXPORT_SYMBOL_GPL(pci_restore_bars);
1168 EXPORT_SYMBOL(pci_enable_device_bars);
1169 EXPORT_SYMBOL(pci_enable_device);
1170 EXPORT_SYMBOL(pci_disable_device);
1171 EXPORT_SYMBOL(pci_find_capability);
1172 EXPORT_SYMBOL(pci_bus_find_capability);
1173 EXPORT_SYMBOL(pci_release_regions);
1174 EXPORT_SYMBOL(pci_request_regions);
1175 EXPORT_SYMBOL(pci_release_region);
1176 EXPORT_SYMBOL(pci_request_region);
1177 EXPORT_SYMBOL(pci_set_master);
1178 EXPORT_SYMBOL(pci_set_mwi);
1179 EXPORT_SYMBOL(pci_clear_mwi);
1180 EXPORT_SYMBOL_GPL(pci_intx);
1181 EXPORT_SYMBOL(pci_set_dma_mask);
1182 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
1183 EXPORT_SYMBOL(pci_assign_resource);
1184 EXPORT_SYMBOL(pci_find_parent_resource);
1186 EXPORT_SYMBOL(pci_set_power_state);
1187 EXPORT_SYMBOL(pci_save_state);
1188 EXPORT_SYMBOL(pci_restore_state);
1189 EXPORT_SYMBOL(pci_enable_wake);
1191 /* Quirk info */
1193 EXPORT_SYMBOL(isa_dma_bridge_buggy);
1194 EXPORT_SYMBOL(pci_pci_problems);