PCI: power management: remove noise on non-manageable hw
[linux-2.6/mini2440.git] / drivers / pci / pci.c
blob7ae709024456d15e5aef0116addcee00b07c191e
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;
396 * If the device or the parent bridge can't support PCI PM, ignore
397 * the request if we're doing anything besides putting it into D0
398 * (which would only happen on boot).
400 if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
401 return 0;
403 /* Validate current state:
404 * Can enter D0 from any state, but if we can only go deeper
405 * to sleep if we're already in a low power state
407 if (state != PCI_D0 && dev->current_state > state) {
408 printk(KERN_ERR "%s(): %s: state=%d, current state=%d\n",
409 __FUNCTION__, pci_name(dev), state, dev->current_state);
410 return -EINVAL;
411 } else if (dev->current_state == state)
412 return 0; /* we're already there */
415 /* find PCI PM capability in list */
416 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
418 /* abort if the device doesn't support PM capabilities */
419 if (!pm)
420 return -EIO;
422 pci_read_config_word(dev,pm + PCI_PM_PMC,&pmc);
423 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
424 printk(KERN_DEBUG
425 "PCI: %s has unsupported PM cap regs version (%u)\n",
426 pci_name(dev), pmc & PCI_PM_CAP_VER_MASK);
427 return -EIO;
430 /* check if this device supports the desired state */
431 if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
432 return -EIO;
433 else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2))
434 return -EIO;
436 pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
438 /* If we're (effectively) in D3, force entire word to 0.
439 * This doesn't affect PME_Status, disables PME_En, and
440 * sets PowerState to 0.
442 switch (dev->current_state) {
443 case PCI_D0:
444 case PCI_D1:
445 case PCI_D2:
446 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
447 pmcsr |= state;
448 break;
449 case PCI_UNKNOWN: /* Boot-up */
450 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
451 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
452 need_restore = 1;
453 /* Fall-through: force to D0 */
454 default:
455 pmcsr = 0;
456 break;
459 /* enter specified state */
460 pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
462 /* Mandatory power management transition delays */
463 /* see PCI PM 1.1 5.6.1 table 18 */
464 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
465 msleep(pci_pm_d3_delay);
466 else if (state == PCI_D2 || dev->current_state == PCI_D2)
467 udelay(200);
470 * Give firmware a chance to be called, such as ACPI _PRx, _PSx
471 * Firmware method after native method ?
473 if (platform_pci_set_power_state)
474 platform_pci_set_power_state(dev, state);
476 dev->current_state = state;
478 /* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
479 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
480 * from D3hot to D0 _may_ perform an internal reset, thereby
481 * going to "D0 Uninitialized" rather than "D0 Initialized".
482 * For example, at least some versions of the 3c905B and the
483 * 3c556B exhibit this behaviour.
485 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
486 * devices in a D3hot state at boot. Consequently, we need to
487 * restore at least the BARs so that the device will be
488 * accessible to its driver.
490 if (need_restore)
491 pci_restore_bars(dev);
493 return 0;
496 int (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
499 * pci_choose_state - Choose the power state of a PCI device
500 * @dev: PCI device to be suspended
501 * @state: target sleep state for the whole system. This is the value
502 * that is passed to suspend() function.
504 * Returns PCI power state suitable for given device and given system
505 * message.
508 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
510 int ret;
512 if (!pci_find_capability(dev, PCI_CAP_ID_PM))
513 return PCI_D0;
515 if (platform_pci_choose_state) {
516 ret = platform_pci_choose_state(dev, state);
517 if (ret >= 0)
518 state.event = ret;
521 switch (state.event) {
522 case PM_EVENT_ON:
523 return PCI_D0;
524 case PM_EVENT_FREEZE:
525 case PM_EVENT_PRETHAW:
526 /* REVISIT both freeze and pre-thaw "should" use D0 */
527 case PM_EVENT_SUSPEND:
528 return PCI_D3hot;
529 default:
530 printk("Unrecognized suspend event %d\n", state.event);
531 BUG();
533 return PCI_D0;
536 EXPORT_SYMBOL(pci_choose_state);
538 static int pci_save_pcie_state(struct pci_dev *dev)
540 int pos, i = 0;
541 struct pci_cap_saved_state *save_state;
542 u16 *cap;
544 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
545 if (pos <= 0)
546 return 0;
548 save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);
549 if (!save_state) {
550 dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
551 return -ENOMEM;
553 cap = (u16 *)&save_state->data[0];
555 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
556 pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
557 pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
558 pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
559 pci_add_saved_cap(dev, save_state);
560 return 0;
563 static void pci_restore_pcie_state(struct pci_dev *dev)
565 int i = 0, pos;
566 struct pci_cap_saved_state *save_state;
567 u16 *cap;
569 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
570 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
571 if (!save_state || pos <= 0)
572 return;
573 cap = (u16 *)&save_state->data[0];
575 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
576 pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
577 pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
578 pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
579 pci_remove_saved_cap(save_state);
580 kfree(save_state);
584 static int pci_save_pcix_state(struct pci_dev *dev)
586 int pos, i = 0;
587 struct pci_cap_saved_state *save_state;
588 u16 *cap;
590 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
591 if (pos <= 0)
592 return 0;
594 save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);
595 if (!save_state) {
596 dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
597 return -ENOMEM;
599 cap = (u16 *)&save_state->data[0];
601 pci_read_config_word(dev, pos + PCI_X_CMD, &cap[i++]);
602 pci_add_saved_cap(dev, save_state);
603 return 0;
606 static void pci_restore_pcix_state(struct pci_dev *dev)
608 int i = 0, pos;
609 struct pci_cap_saved_state *save_state;
610 u16 *cap;
612 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
613 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
614 if (!save_state || pos <= 0)
615 return;
616 cap = (u16 *)&save_state->data[0];
618 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
619 pci_remove_saved_cap(save_state);
620 kfree(save_state);
625 * pci_save_state - save the PCI configuration space of a device before suspending
626 * @dev: - PCI device that we're dealing with
629 pci_save_state(struct pci_dev *dev)
631 int i;
632 /* XXX: 100% dword access ok here? */
633 for (i = 0; i < 16; i++)
634 pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
635 if ((i = pci_save_msi_state(dev)) != 0)
636 return i;
637 if ((i = pci_save_msix_state(dev)) != 0)
638 return i;
639 if ((i = pci_save_pcie_state(dev)) != 0)
640 return i;
641 if ((i = pci_save_pcix_state(dev)) != 0)
642 return i;
643 return 0;
646 /**
647 * pci_restore_state - Restore the saved state of a PCI device
648 * @dev: - PCI device that we're dealing with
650 int
651 pci_restore_state(struct pci_dev *dev)
653 int i;
654 int val;
656 /* PCI Express register must be restored first */
657 pci_restore_pcie_state(dev);
660 * The Base Address register should be programmed before the command
661 * register(s)
663 for (i = 15; i >= 0; i--) {
664 pci_read_config_dword(dev, i * 4, &val);
665 if (val != dev->saved_config_space[i]) {
666 printk(KERN_DEBUG "PM: Writing back config space on "
667 "device %s at offset %x (was %x, writing %x)\n",
668 pci_name(dev), i,
669 val, (int)dev->saved_config_space[i]);
670 pci_write_config_dword(dev,i * 4,
671 dev->saved_config_space[i]);
674 pci_restore_pcix_state(dev);
675 pci_restore_msi_state(dev);
676 pci_restore_msix_state(dev);
677 return 0;
680 static int do_pci_enable_device(struct pci_dev *dev, int bars)
682 int err;
684 err = pci_set_power_state(dev, PCI_D0);
685 if (err < 0 && err != -EIO)
686 return err;
687 err = pcibios_enable_device(dev, bars);
688 if (err < 0)
689 return err;
690 pci_fixup_device(pci_fixup_enable, dev);
692 return 0;
696 * __pci_reenable_device - Resume abandoned device
697 * @dev: PCI device to be resumed
699 * Note this function is a backend of pci_default_resume and is not supposed
700 * to be called by normal code, write proper resume handler and use it instead.
703 __pci_reenable_device(struct pci_dev *dev)
705 if (atomic_read(&dev->enable_cnt))
706 return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
707 return 0;
711 * pci_enable_device_bars - Initialize some of a device for use
712 * @dev: PCI device to be initialized
713 * @bars: bitmask of BAR's that must be configured
715 * Initialize device before it's used by a driver. Ask low-level code
716 * to enable selected I/O and memory resources. Wake up the device if it
717 * was suspended. Beware, this function can fail.
720 pci_enable_device_bars(struct pci_dev *dev, int bars)
722 int err;
724 if (atomic_add_return(1, &dev->enable_cnt) > 1)
725 return 0; /* already enabled */
727 err = do_pci_enable_device(dev, bars);
728 if (err < 0)
729 atomic_dec(&dev->enable_cnt);
730 return err;
734 * pci_enable_device - Initialize device before it's used by a driver.
735 * @dev: PCI device to be initialized
737 * Initialize device before it's used by a driver. Ask low-level code
738 * to enable I/O and memory. Wake up the device if it was suspended.
739 * Beware, this function can fail.
741 * Note we don't actually enable the device many times if we call
742 * this function repeatedly (we just increment the count).
744 int pci_enable_device(struct pci_dev *dev)
746 return pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
750 * pcibios_disable_device - disable arch specific PCI resources for device dev
751 * @dev: the PCI device to disable
753 * Disables architecture specific PCI resources for the device. This
754 * is the default implementation. Architecture implementations can
755 * override this.
757 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
760 * pci_disable_device - Disable PCI device after use
761 * @dev: PCI device to be disabled
763 * Signal to the system that the PCI device is not in use by the system
764 * anymore. This only involves disabling PCI bus-mastering, if active.
766 * Note we don't actually disable the device until all callers of
767 * pci_device_enable() have called pci_device_disable().
769 void
770 pci_disable_device(struct pci_dev *dev)
772 u16 pci_command;
774 if (atomic_sub_return(1, &dev->enable_cnt) != 0)
775 return;
777 if (dev->msi_enabled)
778 disable_msi_mode(dev, pci_find_capability(dev, PCI_CAP_ID_MSI),
779 PCI_CAP_ID_MSI);
780 if (dev->msix_enabled)
781 disable_msi_mode(dev, pci_find_capability(dev, PCI_CAP_ID_MSI),
782 PCI_CAP_ID_MSIX);
784 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
785 if (pci_command & PCI_COMMAND_MASTER) {
786 pci_command &= ~PCI_COMMAND_MASTER;
787 pci_write_config_word(dev, PCI_COMMAND, pci_command);
789 dev->is_busmaster = 0;
791 pcibios_disable_device(dev);
795 * pci_enable_wake - enable device to generate PME# when suspended
796 * @dev: - PCI device to operate on
797 * @state: - Current state of device.
798 * @enable: - Flag to enable or disable generation
800 * Set the bits in the device's PM Capabilities to generate PME# when
801 * the system is suspended.
803 * -EIO is returned if device doesn't have PM Capabilities.
804 * -EINVAL is returned if device supports it, but can't generate wake events.
805 * 0 if operation is successful.
808 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
810 int pm;
811 u16 value;
813 /* find PCI PM capability in list */
814 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
816 /* If device doesn't support PM Capabilities, but request is to disable
817 * wake events, it's a nop; otherwise fail */
818 if (!pm)
819 return enable ? -EIO : 0;
821 /* Check device's ability to generate PME# */
822 pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
824 value &= PCI_PM_CAP_PME_MASK;
825 value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */
827 /* Check if it can generate PME# from requested state. */
828 if (!value || !(value & (1 << state)))
829 return enable ? -EINVAL : 0;
831 pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
833 /* Clear PME_Status by writing 1 to it and enable PME# */
834 value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
836 if (!enable)
837 value &= ~PCI_PM_CTRL_PME_ENABLE;
839 pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
841 return 0;
845 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
847 u8 pin;
849 pin = dev->pin;
850 if (!pin)
851 return -1;
852 pin--;
853 while (dev->bus->self) {
854 pin = (pin + PCI_SLOT(dev->devfn)) % 4;
855 dev = dev->bus->self;
857 *bridge = dev;
858 return pin;
862 * pci_release_region - Release a PCI bar
863 * @pdev: PCI device whose resources were previously reserved by pci_request_region
864 * @bar: BAR to release
866 * Releases the PCI I/O and memory resources previously reserved by a
867 * successful call to pci_request_region. Call this function only
868 * after all use of the PCI regions has ceased.
870 void pci_release_region(struct pci_dev *pdev, int bar)
872 if (pci_resource_len(pdev, bar) == 0)
873 return;
874 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
875 release_region(pci_resource_start(pdev, bar),
876 pci_resource_len(pdev, bar));
877 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
878 release_mem_region(pci_resource_start(pdev, bar),
879 pci_resource_len(pdev, bar));
883 * pci_request_region - Reserved PCI I/O and memory resource
884 * @pdev: PCI device whose resources are to be reserved
885 * @bar: BAR to be reserved
886 * @res_name: Name to be associated with resource.
888 * Mark the PCI region associated with PCI device @pdev BR @bar as
889 * being reserved by owner @res_name. Do not access any
890 * address inside the PCI regions unless this call returns
891 * successfully.
893 * Returns 0 on success, or %EBUSY on error. A warning
894 * message is also printed on failure.
896 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
898 if (pci_resource_len(pdev, bar) == 0)
899 return 0;
901 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
902 if (!request_region(pci_resource_start(pdev, bar),
903 pci_resource_len(pdev, bar), res_name))
904 goto err_out;
906 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
907 if (!request_mem_region(pci_resource_start(pdev, bar),
908 pci_resource_len(pdev, bar), res_name))
909 goto err_out;
912 return 0;
914 err_out:
915 printk (KERN_WARNING "PCI: Unable to reserve %s region #%d:%llx@%llx "
916 "for device %s\n",
917 pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
918 bar + 1, /* PCI BAR # */
919 (unsigned long long)pci_resource_len(pdev, bar),
920 (unsigned long long)pci_resource_start(pdev, bar),
921 pci_name(pdev));
922 return -EBUSY;
926 * pci_release_selected_regions - Release selected PCI I/O and memory resources
927 * @pdev: PCI device whose resources were previously reserved
928 * @bars: Bitmask of BARs to be released
930 * Release selected PCI I/O and memory resources previously reserved.
931 * Call this function only after all use of the PCI regions has ceased.
933 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
935 int i;
937 for (i = 0; i < 6; i++)
938 if (bars & (1 << i))
939 pci_release_region(pdev, i);
943 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
944 * @pdev: PCI device whose resources are to be reserved
945 * @bars: Bitmask of BARs to be requested
946 * @res_name: Name to be associated with resource
948 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
949 const char *res_name)
951 int i;
953 for (i = 0; i < 6; i++)
954 if (bars & (1 << i))
955 if(pci_request_region(pdev, i, res_name))
956 goto err_out;
957 return 0;
959 err_out:
960 while(--i >= 0)
961 if (bars & (1 << i))
962 pci_release_region(pdev, i);
964 return -EBUSY;
968 * pci_release_regions - Release reserved PCI I/O and memory resources
969 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
971 * Releases all PCI I/O and memory resources previously reserved by a
972 * successful call to pci_request_regions. Call this function only
973 * after all use of the PCI regions has ceased.
976 void pci_release_regions(struct pci_dev *pdev)
978 pci_release_selected_regions(pdev, (1 << 6) - 1);
982 * pci_request_regions - Reserved PCI I/O and memory resources
983 * @pdev: PCI device whose resources are to be reserved
984 * @res_name: Name to be associated with resource.
986 * Mark all PCI regions associated with PCI device @pdev as
987 * being reserved by owner @res_name. Do not access any
988 * address inside the PCI regions unless this call returns
989 * successfully.
991 * Returns 0 on success, or %EBUSY on error. A warning
992 * message is also printed on failure.
994 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
996 return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
1000 * pci_set_master - enables bus-mastering for device dev
1001 * @dev: the PCI device to enable
1003 * Enables bus-mastering on the device and calls pcibios_set_master()
1004 * to do the needed arch specific settings.
1006 void
1007 pci_set_master(struct pci_dev *dev)
1009 u16 cmd;
1011 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1012 if (! (cmd & PCI_COMMAND_MASTER)) {
1013 pr_debug("PCI: Enabling bus mastering for device %s\n", pci_name(dev));
1014 cmd |= PCI_COMMAND_MASTER;
1015 pci_write_config_word(dev, PCI_COMMAND, cmd);
1017 dev->is_busmaster = 1;
1018 pcibios_set_master(dev);
1021 #ifdef PCI_DISABLE_MWI
1022 int pci_set_mwi(struct pci_dev *dev)
1024 return 0;
1027 void pci_clear_mwi(struct pci_dev *dev)
1031 #else
1033 #ifndef PCI_CACHE_LINE_BYTES
1034 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
1035 #endif
1037 /* This can be overridden by arch code. */
1038 /* Don't forget this is measured in 32-bit words, not bytes */
1039 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
1042 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1043 * @dev: the PCI device for which MWI is to be enabled
1045 * Helper function for pci_set_mwi.
1046 * Originally copied from drivers/net/acenic.c.
1047 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1049 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1051 static int
1052 pci_set_cacheline_size(struct pci_dev *dev)
1054 u8 cacheline_size;
1056 if (!pci_cache_line_size)
1057 return -EINVAL; /* The system doesn't support MWI. */
1059 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1060 equal to or multiple of the right value. */
1061 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1062 if (cacheline_size >= pci_cache_line_size &&
1063 (cacheline_size % pci_cache_line_size) == 0)
1064 return 0;
1066 /* Write the correct value. */
1067 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1068 /* Read it back. */
1069 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1070 if (cacheline_size == pci_cache_line_size)
1071 return 0;
1073 printk(KERN_DEBUG "PCI: cache line size of %d is not supported "
1074 "by device %s\n", pci_cache_line_size << 2, pci_name(dev));
1076 return -EINVAL;
1080 * pci_set_mwi - enables memory-write-invalidate PCI transaction
1081 * @dev: the PCI device for which MWI is enabled
1083 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND,
1084 * and then calls @pcibios_set_mwi to do the needed arch specific
1085 * operations or a generic mwi-prep function.
1087 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1090 pci_set_mwi(struct pci_dev *dev)
1092 int rc;
1093 u16 cmd;
1095 rc = pci_set_cacheline_size(dev);
1096 if (rc)
1097 return rc;
1099 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1100 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1101 pr_debug("PCI: Enabling Mem-Wr-Inval for device %s\n", pci_name(dev));
1102 cmd |= PCI_COMMAND_INVALIDATE;
1103 pci_write_config_word(dev, PCI_COMMAND, cmd);
1106 return 0;
1110 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1111 * @dev: the PCI device to disable
1113 * Disables PCI Memory-Write-Invalidate transaction on the device
1115 void
1116 pci_clear_mwi(struct pci_dev *dev)
1118 u16 cmd;
1120 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1121 if (cmd & PCI_COMMAND_INVALIDATE) {
1122 cmd &= ~PCI_COMMAND_INVALIDATE;
1123 pci_write_config_word(dev, PCI_COMMAND, cmd);
1126 #endif /* ! PCI_DISABLE_MWI */
1129 * pci_intx - enables/disables PCI INTx for device dev
1130 * @pdev: the PCI device to operate on
1131 * @enable: boolean: whether to enable or disable PCI INTx
1133 * Enables/disables PCI INTx for device dev
1135 void
1136 pci_intx(struct pci_dev *pdev, int enable)
1138 u16 pci_command, new;
1140 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1142 if (enable) {
1143 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1144 } else {
1145 new = pci_command | PCI_COMMAND_INTX_DISABLE;
1148 if (new != pci_command) {
1149 pci_write_config_word(pdev, PCI_COMMAND, new);
1153 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
1155 * These can be overridden by arch-specific implementations
1158 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
1160 if (!pci_dma_supported(dev, mask))
1161 return -EIO;
1163 dev->dma_mask = mask;
1165 return 0;
1169 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
1171 if (!pci_dma_supported(dev, mask))
1172 return -EIO;
1174 dev->dev.coherent_dma_mask = mask;
1176 return 0;
1178 #endif
1181 * pci_select_bars - Make BAR mask from the type of resource
1182 * @pdev: the PCI device for which BAR mask is made
1183 * @flags: resource type mask to be selected
1185 * This helper routine makes bar mask from the type of resource.
1187 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
1189 int i, bars = 0;
1190 for (i = 0; i < PCI_NUM_RESOURCES; i++)
1191 if (pci_resource_flags(dev, i) & flags)
1192 bars |= (1 << i);
1193 return bars;
1196 static int __devinit pci_init(void)
1198 struct pci_dev *dev = NULL;
1200 while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
1201 pci_fixup_device(pci_fixup_final, dev);
1203 return 0;
1206 static int __devinit pci_setup(char *str)
1208 while (str) {
1209 char *k = strchr(str, ',');
1210 if (k)
1211 *k++ = 0;
1212 if (*str && (str = pcibios_setup(str)) && *str) {
1213 if (!strcmp(str, "nomsi")) {
1214 pci_no_msi();
1215 } else {
1216 printk(KERN_ERR "PCI: Unknown option `%s'\n",
1217 str);
1220 str = k;
1222 return 0;
1224 early_param("pci", pci_setup);
1226 device_initcall(pci_init);
1228 EXPORT_SYMBOL_GPL(pci_restore_bars);
1229 EXPORT_SYMBOL(pci_enable_device_bars);
1230 EXPORT_SYMBOL(pci_enable_device);
1231 EXPORT_SYMBOL(pci_disable_device);
1232 EXPORT_SYMBOL(pci_find_capability);
1233 EXPORT_SYMBOL(pci_bus_find_capability);
1234 EXPORT_SYMBOL(pci_release_regions);
1235 EXPORT_SYMBOL(pci_request_regions);
1236 EXPORT_SYMBOL(pci_release_region);
1237 EXPORT_SYMBOL(pci_request_region);
1238 EXPORT_SYMBOL(pci_release_selected_regions);
1239 EXPORT_SYMBOL(pci_request_selected_regions);
1240 EXPORT_SYMBOL(pci_set_master);
1241 EXPORT_SYMBOL(pci_set_mwi);
1242 EXPORT_SYMBOL(pci_clear_mwi);
1243 EXPORT_SYMBOL_GPL(pci_intx);
1244 EXPORT_SYMBOL(pci_set_dma_mask);
1245 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
1246 EXPORT_SYMBOL(pci_assign_resource);
1247 EXPORT_SYMBOL(pci_find_parent_resource);
1248 EXPORT_SYMBOL(pci_select_bars);
1250 EXPORT_SYMBOL(pci_set_power_state);
1251 EXPORT_SYMBOL(pci_save_state);
1252 EXPORT_SYMBOL(pci_restore_state);
1253 EXPORT_SYMBOL(pci_enable_wake);