[IA64] swiotlb bug fixes
[linux-2.6/kvm.git] / drivers / pci / pci.c
blob206c834d263a8ce3de6775fa2398a948756007b0
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.
690 pci_enable_device_bars(struct pci_dev *dev, int bars)
692 int err;
694 err = pci_set_power_state(dev, PCI_D0);
695 if (err < 0 && err != -EIO)
696 return err;
697 err = pcibios_enable_device(dev, bars);
698 if (err < 0)
699 return err;
700 return 0;
704 * __pci_enable_device - Initialize device before it's used by a driver.
705 * @dev: PCI device to be initialized
707 * Initialize device before it's used by a driver. Ask low-level code
708 * to enable I/O and memory. Wake up the device if it was suspended.
709 * Beware, this function can fail.
711 * Note this function is a backend and is not supposed to be called by
712 * normal code, use pci_enable_device() instead.
715 __pci_enable_device(struct pci_dev *dev)
717 int err;
719 err = pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
720 if (err)
721 return err;
722 pci_fixup_device(pci_fixup_enable, dev);
723 return 0;
727 * pci_enable_device - Initialize device before it's used by a driver.
728 * @dev: PCI device to be initialized
730 * Initialize device before it's used by a driver. Ask low-level code
731 * to enable I/O and memory. Wake up the device if it was suspended.
732 * Beware, this function can fail.
734 * Note we don't actually enable the device many times if we call
735 * this function repeatedly (we just increment the count).
737 int pci_enable_device(struct pci_dev *dev)
739 int result;
740 if (atomic_add_return(1, &dev->enable_cnt) > 1)
741 return 0; /* already enabled */
742 result = __pci_enable_device(dev);
743 if (result < 0)
744 atomic_dec(&dev->enable_cnt);
745 return result;
749 * pcibios_disable_device - disable arch specific PCI resources for device dev
750 * @dev: the PCI device to disable
752 * Disables architecture specific PCI resources for the device. This
753 * is the default implementation. Architecture implementations can
754 * override this.
756 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
759 * pci_disable_device - Disable PCI device after use
760 * @dev: PCI device to be disabled
762 * Signal to the system that the PCI device is not in use by the system
763 * anymore. This only involves disabling PCI bus-mastering, if active.
765 * Note we don't actually disable the device until all callers of
766 * pci_device_enable() have called pci_device_disable().
768 void
769 pci_disable_device(struct pci_dev *dev)
771 u16 pci_command;
773 if (atomic_sub_return(1, &dev->enable_cnt) != 0)
774 return;
776 if (dev->msi_enabled)
777 disable_msi_mode(dev, pci_find_capability(dev, PCI_CAP_ID_MSI),
778 PCI_CAP_ID_MSI);
779 if (dev->msix_enabled)
780 disable_msi_mode(dev, pci_find_capability(dev, PCI_CAP_ID_MSI),
781 PCI_CAP_ID_MSIX);
783 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
784 if (pci_command & PCI_COMMAND_MASTER) {
785 pci_command &= ~PCI_COMMAND_MASTER;
786 pci_write_config_word(dev, PCI_COMMAND, pci_command);
788 dev->is_busmaster = 0;
790 pcibios_disable_device(dev);
794 * pci_enable_wake - enable device to generate PME# when suspended
795 * @dev: - PCI device to operate on
796 * @state: - Current state of device.
797 * @enable: - Flag to enable or disable generation
799 * Set the bits in the device's PM Capabilities to generate PME# when
800 * the system is suspended.
802 * -EIO is returned if device doesn't have PM Capabilities.
803 * -EINVAL is returned if device supports it, but can't generate wake events.
804 * 0 if operation is successful.
807 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
809 int pm;
810 u16 value;
812 /* find PCI PM capability in list */
813 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
815 /* If device doesn't support PM Capabilities, but request is to disable
816 * wake events, it's a nop; otherwise fail */
817 if (!pm)
818 return enable ? -EIO : 0;
820 /* Check device's ability to generate PME# */
821 pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
823 value &= PCI_PM_CAP_PME_MASK;
824 value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */
826 /* Check if it can generate PME# from requested state. */
827 if (!value || !(value & (1 << state)))
828 return enable ? -EINVAL : 0;
830 pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
832 /* Clear PME_Status by writing 1 to it and enable PME# */
833 value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
835 if (!enable)
836 value &= ~PCI_PM_CTRL_PME_ENABLE;
838 pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
840 return 0;
844 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
846 u8 pin;
848 pin = dev->pin;
849 if (!pin)
850 return -1;
851 pin--;
852 while (dev->bus->self) {
853 pin = (pin + PCI_SLOT(dev->devfn)) % 4;
854 dev = dev->bus->self;
856 *bridge = dev;
857 return pin;
861 * pci_release_region - Release a PCI bar
862 * @pdev: PCI device whose resources were previously reserved by pci_request_region
863 * @bar: BAR to release
865 * Releases the PCI I/O and memory resources previously reserved by a
866 * successful call to pci_request_region. Call this function only
867 * after all use of the PCI regions has ceased.
869 void pci_release_region(struct pci_dev *pdev, int bar)
871 if (pci_resource_len(pdev, bar) == 0)
872 return;
873 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
874 release_region(pci_resource_start(pdev, bar),
875 pci_resource_len(pdev, bar));
876 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
877 release_mem_region(pci_resource_start(pdev, bar),
878 pci_resource_len(pdev, bar));
882 * pci_request_region - Reserved PCI I/O and memory resource
883 * @pdev: PCI device whose resources are to be reserved
884 * @bar: BAR to be reserved
885 * @res_name: Name to be associated with resource.
887 * Mark the PCI region associated with PCI device @pdev BR @bar as
888 * being reserved by owner @res_name. Do not access any
889 * address inside the PCI regions unless this call returns
890 * successfully.
892 * Returns 0 on success, or %EBUSY on error. A warning
893 * message is also printed on failure.
895 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
897 if (pci_resource_len(pdev, bar) == 0)
898 return 0;
900 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
901 if (!request_region(pci_resource_start(pdev, bar),
902 pci_resource_len(pdev, bar), res_name))
903 goto err_out;
905 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
906 if (!request_mem_region(pci_resource_start(pdev, bar),
907 pci_resource_len(pdev, bar), res_name))
908 goto err_out;
911 return 0;
913 err_out:
914 printk (KERN_WARNING "PCI: Unable to reserve %s region #%d:%llx@%llx "
915 "for device %s\n",
916 pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
917 bar + 1, /* PCI BAR # */
918 (unsigned long long)pci_resource_len(pdev, bar),
919 (unsigned long long)pci_resource_start(pdev, bar),
920 pci_name(pdev));
921 return -EBUSY;
926 * pci_release_regions - Release reserved PCI I/O and memory resources
927 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
929 * Releases all PCI I/O and memory resources previously reserved by a
930 * successful call to pci_request_regions. Call this function only
931 * after all use of the PCI regions has ceased.
934 void pci_release_regions(struct pci_dev *pdev)
936 int i;
938 for (i = 0; i < 6; i++)
939 pci_release_region(pdev, i);
943 * pci_request_regions - Reserved PCI I/O and memory resources
944 * @pdev: PCI device whose resources are to be reserved
945 * @res_name: Name to be associated with resource.
947 * Mark all PCI regions associated with PCI device @pdev as
948 * being reserved by owner @res_name. Do not access any
949 * address inside the PCI regions unless this call returns
950 * successfully.
952 * Returns 0 on success, or %EBUSY on error. A warning
953 * message is also printed on failure.
955 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
957 int i;
959 for (i = 0; i < 6; i++)
960 if(pci_request_region(pdev, i, res_name))
961 goto err_out;
962 return 0;
964 err_out:
965 while(--i >= 0)
966 pci_release_region(pdev, i);
968 return -EBUSY;
972 * pci_set_master - enables bus-mastering for device dev
973 * @dev: the PCI device to enable
975 * Enables bus-mastering on the device and calls pcibios_set_master()
976 * to do the needed arch specific settings.
978 void
979 pci_set_master(struct pci_dev *dev)
981 u16 cmd;
983 pci_read_config_word(dev, PCI_COMMAND, &cmd);
984 if (! (cmd & PCI_COMMAND_MASTER)) {
985 pr_debug("PCI: Enabling bus mastering for device %s\n", pci_name(dev));
986 cmd |= PCI_COMMAND_MASTER;
987 pci_write_config_word(dev, PCI_COMMAND, cmd);
989 dev->is_busmaster = 1;
990 pcibios_set_master(dev);
993 #ifdef PCI_DISABLE_MWI
994 int pci_set_mwi(struct pci_dev *dev)
996 return 0;
999 void pci_clear_mwi(struct pci_dev *dev)
1003 #else
1005 #ifndef PCI_CACHE_LINE_BYTES
1006 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
1007 #endif
1009 /* This can be overridden by arch code. */
1010 /* Don't forget this is measured in 32-bit words, not bytes */
1011 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
1014 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1015 * @dev: the PCI device for which MWI is to be enabled
1017 * Helper function for pci_set_mwi.
1018 * Originally copied from drivers/net/acenic.c.
1019 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1021 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1023 static int
1024 pci_set_cacheline_size(struct pci_dev *dev)
1026 u8 cacheline_size;
1028 if (!pci_cache_line_size)
1029 return -EINVAL; /* The system doesn't support MWI. */
1031 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1032 equal to or multiple of the right value. */
1033 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1034 if (cacheline_size >= pci_cache_line_size &&
1035 (cacheline_size % pci_cache_line_size) == 0)
1036 return 0;
1038 /* Write the correct value. */
1039 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1040 /* Read it back. */
1041 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1042 if (cacheline_size == pci_cache_line_size)
1043 return 0;
1045 printk(KERN_DEBUG "PCI: cache line size of %d is not supported "
1046 "by device %s\n", pci_cache_line_size << 2, pci_name(dev));
1048 return -EINVAL;
1052 * pci_set_mwi - enables memory-write-invalidate PCI transaction
1053 * @dev: the PCI device for which MWI is enabled
1055 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND,
1056 * and then calls @pcibios_set_mwi to do the needed arch specific
1057 * operations or a generic mwi-prep function.
1059 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1062 pci_set_mwi(struct pci_dev *dev)
1064 int rc;
1065 u16 cmd;
1067 rc = pci_set_cacheline_size(dev);
1068 if (rc)
1069 return rc;
1071 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1072 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1073 pr_debug("PCI: Enabling Mem-Wr-Inval for device %s\n", pci_name(dev));
1074 cmd |= PCI_COMMAND_INVALIDATE;
1075 pci_write_config_word(dev, PCI_COMMAND, cmd);
1078 return 0;
1082 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1083 * @dev: the PCI device to disable
1085 * Disables PCI Memory-Write-Invalidate transaction on the device
1087 void
1088 pci_clear_mwi(struct pci_dev *dev)
1090 u16 cmd;
1092 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1093 if (cmd & PCI_COMMAND_INVALIDATE) {
1094 cmd &= ~PCI_COMMAND_INVALIDATE;
1095 pci_write_config_word(dev, PCI_COMMAND, cmd);
1098 #endif /* ! PCI_DISABLE_MWI */
1101 * pci_intx - enables/disables PCI INTx for device dev
1102 * @pdev: the PCI device to operate on
1103 * @enable: boolean: whether to enable or disable PCI INTx
1105 * Enables/disables PCI INTx for device dev
1107 void
1108 pci_intx(struct pci_dev *pdev, int enable)
1110 u16 pci_command, new;
1112 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1114 if (enable) {
1115 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1116 } else {
1117 new = pci_command | PCI_COMMAND_INTX_DISABLE;
1120 if (new != pci_command) {
1121 pci_write_config_word(pdev, PCI_COMMAND, new);
1125 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
1127 * These can be overridden by arch-specific implementations
1130 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
1132 if (!pci_dma_supported(dev, mask))
1133 return -EIO;
1135 dev->dma_mask = mask;
1137 return 0;
1141 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
1143 if (!pci_dma_supported(dev, mask))
1144 return -EIO;
1146 dev->dev.coherent_dma_mask = mask;
1148 return 0;
1150 #endif
1152 static int __devinit pci_init(void)
1154 struct pci_dev *dev = NULL;
1156 while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
1157 pci_fixup_device(pci_fixup_final, dev);
1159 return 0;
1162 static int __devinit pci_setup(char *str)
1164 while (str) {
1165 char *k = strchr(str, ',');
1166 if (k)
1167 *k++ = 0;
1168 if (*str && (str = pcibios_setup(str)) && *str) {
1169 if (!strcmp(str, "nomsi")) {
1170 pci_no_msi();
1171 } else {
1172 printk(KERN_ERR "PCI: Unknown option `%s'\n",
1173 str);
1176 str = k;
1178 return 0;
1180 early_param("pci", pci_setup);
1182 device_initcall(pci_init);
1184 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
1185 /* FIXME: Some boxes have multiple ISA bridges! */
1186 struct pci_dev *isa_bridge;
1187 EXPORT_SYMBOL(isa_bridge);
1188 #endif
1190 EXPORT_SYMBOL_GPL(pci_restore_bars);
1191 EXPORT_SYMBOL(pci_enable_device_bars);
1192 EXPORT_SYMBOL(pci_enable_device);
1193 EXPORT_SYMBOL(pci_disable_device);
1194 EXPORT_SYMBOL(pci_find_capability);
1195 EXPORT_SYMBOL(pci_bus_find_capability);
1196 EXPORT_SYMBOL(pci_release_regions);
1197 EXPORT_SYMBOL(pci_request_regions);
1198 EXPORT_SYMBOL(pci_release_region);
1199 EXPORT_SYMBOL(pci_request_region);
1200 EXPORT_SYMBOL(pci_set_master);
1201 EXPORT_SYMBOL(pci_set_mwi);
1202 EXPORT_SYMBOL(pci_clear_mwi);
1203 EXPORT_SYMBOL_GPL(pci_intx);
1204 EXPORT_SYMBOL(pci_set_dma_mask);
1205 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
1206 EXPORT_SYMBOL(pci_assign_resource);
1207 EXPORT_SYMBOL(pci_find_parent_resource);
1209 EXPORT_SYMBOL(pci_set_power_state);
1210 EXPORT_SYMBOL(pci_save_state);
1211 EXPORT_SYMBOL(pci_restore_state);
1212 EXPORT_SYMBOL(pci_enable_wake);
1214 /* Quirk info */
1216 EXPORT_SYMBOL(isa_dma_bridge_buggy);
1217 EXPORT_SYMBOL(pci_pci_problems);