sched: push RT tasks from overloaded CPUs
[linux-2.6/kmemtrace.git] / drivers / pci / pci.c
blob71d561fda0a2bb0903cf91ccaf78ae6a9b37f07d
1 /*
2 * $Id: pci.c,v 1.91 1999/01/21 13:34:01 davem Exp $
4 * PCI Bus Services, see include/linux/pci.h for further explanation.
6 * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
7 * David Mosberger-Tang
9 * Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
12 #include <linux/kernel.h>
13 #include <linux/delay.h>
14 #include <linux/init.h>
15 #include <linux/pci.h>
16 #include <linux/pm.h>
17 #include <linux/module.h>
18 #include <linux/spinlock.h>
19 #include <linux/string.h>
20 #include <linux/log2.h>
21 #include <asm/dma.h> /* isa_dma_bridge_buggy */
22 #include "pci.h"
24 unsigned int pci_pm_d3_delay = 10;
26 #ifdef CONFIG_PCI_DOMAINS
27 int pci_domains_supported = 1;
28 #endif
30 #define DEFAULT_CARDBUS_IO_SIZE (256)
31 #define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
32 /* pci=cbmemsize=nnM,cbiosize=nn can override this */
33 unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
34 unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
36 /**
37 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
38 * @bus: pointer to PCI bus structure to search
40 * Given a PCI bus, returns the highest PCI bus number present in the set
41 * including the given PCI bus and its list of child PCI buses.
43 unsigned char pci_bus_max_busnr(struct pci_bus* bus)
45 struct list_head *tmp;
46 unsigned char max, n;
48 max = bus->subordinate;
49 list_for_each(tmp, &bus->children) {
50 n = pci_bus_max_busnr(pci_bus_b(tmp));
51 if(n > max)
52 max = n;
54 return max;
56 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
58 #if 0
59 /**
60 * pci_max_busnr - returns maximum PCI bus number
62 * Returns the highest PCI bus number present in the system global list of
63 * PCI buses.
65 unsigned char __devinit
66 pci_max_busnr(void)
68 struct pci_bus *bus = NULL;
69 unsigned char max, n;
71 max = 0;
72 while ((bus = pci_find_next_bus(bus)) != NULL) {
73 n = pci_bus_max_busnr(bus);
74 if(n > max)
75 max = n;
77 return max;
80 #endif /* 0 */
82 #define PCI_FIND_CAP_TTL 48
84 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
85 u8 pos, int cap, int *ttl)
87 u8 id;
89 while ((*ttl)--) {
90 pci_bus_read_config_byte(bus, devfn, pos, &pos);
91 if (pos < 0x40)
92 break;
93 pos &= ~3;
94 pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
95 &id);
96 if (id == 0xff)
97 break;
98 if (id == cap)
99 return pos;
100 pos += PCI_CAP_LIST_NEXT;
102 return 0;
105 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
106 u8 pos, int cap)
108 int ttl = PCI_FIND_CAP_TTL;
110 return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
113 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
115 return __pci_find_next_cap(dev->bus, dev->devfn,
116 pos + PCI_CAP_LIST_NEXT, cap);
118 EXPORT_SYMBOL_GPL(pci_find_next_capability);
120 static int __pci_bus_find_cap_start(struct pci_bus *bus,
121 unsigned int devfn, u8 hdr_type)
123 u16 status;
125 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
126 if (!(status & PCI_STATUS_CAP_LIST))
127 return 0;
129 switch (hdr_type) {
130 case PCI_HEADER_TYPE_NORMAL:
131 case PCI_HEADER_TYPE_BRIDGE:
132 return PCI_CAPABILITY_LIST;
133 case PCI_HEADER_TYPE_CARDBUS:
134 return PCI_CB_CAPABILITY_LIST;
135 default:
136 return 0;
139 return 0;
143 * pci_find_capability - query for devices' capabilities
144 * @dev: PCI device to query
145 * @cap: capability code
147 * Tell if a device supports a given PCI capability.
148 * Returns the address of the requested capability structure within the
149 * device's PCI configuration space or 0 in case the device does not
150 * support it. Possible values for @cap:
152 * %PCI_CAP_ID_PM Power Management
153 * %PCI_CAP_ID_AGP Accelerated Graphics Port
154 * %PCI_CAP_ID_VPD Vital Product Data
155 * %PCI_CAP_ID_SLOTID Slot Identification
156 * %PCI_CAP_ID_MSI Message Signalled Interrupts
157 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
158 * %PCI_CAP_ID_PCIX PCI-X
159 * %PCI_CAP_ID_EXP PCI Express
161 int pci_find_capability(struct pci_dev *dev, int cap)
163 int pos;
165 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
166 if (pos)
167 pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
169 return pos;
173 * pci_bus_find_capability - query for devices' capabilities
174 * @bus: the PCI bus to query
175 * @devfn: PCI device to query
176 * @cap: capability code
178 * Like pci_find_capability() but works for pci devices that do not have a
179 * pci_dev structure set up yet.
181 * Returns the address of the requested capability structure within the
182 * device's PCI configuration space or 0 in case the device does not
183 * support it.
185 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
187 int pos;
188 u8 hdr_type;
190 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
192 pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
193 if (pos)
194 pos = __pci_find_next_cap(bus, devfn, pos, cap);
196 return pos;
200 * pci_find_ext_capability - Find an extended capability
201 * @dev: PCI device to query
202 * @cap: capability code
204 * Returns the address of the requested extended capability structure
205 * within the device's PCI configuration space or 0 if the device does
206 * not support it. Possible values for @cap:
208 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
209 * %PCI_EXT_CAP_ID_VC Virtual Channel
210 * %PCI_EXT_CAP_ID_DSN Device Serial Number
211 * %PCI_EXT_CAP_ID_PWR Power Budgeting
213 int pci_find_ext_capability(struct pci_dev *dev, int cap)
215 u32 header;
216 int ttl = 480; /* 3840 bytes, minimum 8 bytes per capability */
217 int pos = 0x100;
219 if (dev->cfg_size <= 256)
220 return 0;
222 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
223 return 0;
226 * If we have no capabilities, this is indicated by cap ID,
227 * cap version and next pointer all being 0.
229 if (header == 0)
230 return 0;
232 while (ttl-- > 0) {
233 if (PCI_EXT_CAP_ID(header) == cap)
234 return pos;
236 pos = PCI_EXT_CAP_NEXT(header);
237 if (pos < 0x100)
238 break;
240 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
241 break;
244 return 0;
246 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
248 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
250 int rc, ttl = PCI_FIND_CAP_TTL;
251 u8 cap, mask;
253 if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
254 mask = HT_3BIT_CAP_MASK;
255 else
256 mask = HT_5BIT_CAP_MASK;
258 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
259 PCI_CAP_ID_HT, &ttl);
260 while (pos) {
261 rc = pci_read_config_byte(dev, pos + 3, &cap);
262 if (rc != PCIBIOS_SUCCESSFUL)
263 return 0;
265 if ((cap & mask) == ht_cap)
266 return pos;
268 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
269 pos + PCI_CAP_LIST_NEXT,
270 PCI_CAP_ID_HT, &ttl);
273 return 0;
276 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
277 * @dev: PCI device to query
278 * @pos: Position from which to continue searching
279 * @ht_cap: Hypertransport capability code
281 * To be used in conjunction with pci_find_ht_capability() to search for
282 * all capabilities matching @ht_cap. @pos should always be a value returned
283 * from pci_find_ht_capability().
285 * NB. To be 100% safe against broken PCI devices, the caller should take
286 * steps to avoid an infinite loop.
288 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
290 return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
292 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
295 * pci_find_ht_capability - query a device's Hypertransport capabilities
296 * @dev: PCI device to query
297 * @ht_cap: Hypertransport capability code
299 * Tell if a device supports a given Hypertransport capability.
300 * Returns an address within the device's PCI configuration space
301 * or 0 in case the device does not support the request capability.
302 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
303 * which has a Hypertransport capability matching @ht_cap.
305 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
307 int pos;
309 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
310 if (pos)
311 pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
313 return pos;
315 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
318 * pci_find_parent_resource - return resource region of parent bus of given region
319 * @dev: PCI device structure contains resources to be searched
320 * @res: child resource record for which parent is sought
322 * For given resource region of given device, return the resource
323 * region of parent bus the given region is contained in or where
324 * it should be allocated from.
326 struct resource *
327 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
329 const struct pci_bus *bus = dev->bus;
330 int i;
331 struct resource *best = NULL;
333 for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
334 struct resource *r = bus->resource[i];
335 if (!r)
336 continue;
337 if (res->start && !(res->start >= r->start && res->end <= r->end))
338 continue; /* Not contained */
339 if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
340 continue; /* Wrong type */
341 if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
342 return r; /* Exact match */
343 if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
344 best = r; /* Approximating prefetchable by non-prefetchable */
346 return best;
350 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
351 * @dev: PCI device to have its BARs restored
353 * Restore the BAR values for a given device, so as to make it
354 * accessible by its driver.
356 void
357 pci_restore_bars(struct pci_dev *dev)
359 int i, numres;
361 switch (dev->hdr_type) {
362 case PCI_HEADER_TYPE_NORMAL:
363 numres = 6;
364 break;
365 case PCI_HEADER_TYPE_BRIDGE:
366 numres = 2;
367 break;
368 case PCI_HEADER_TYPE_CARDBUS:
369 numres = 1;
370 break;
371 default:
372 /* Should never get here, but just in case... */
373 return;
376 for (i = 0; i < numres; i ++)
377 pci_update_resource(dev, &dev->resource[i], i);
380 int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t t);
383 * pci_set_power_state - Set the power state of a PCI device
384 * @dev: PCI device to be suspended
385 * @state: PCI power state (D0, D1, D2, D3hot, D3cold) we're entering
387 * Transition a device to a new power state, using the Power Management
388 * Capabilities in the device's config space.
390 * RETURN VALUE:
391 * -EINVAL if trying to enter a lower state than we're already in.
392 * 0 if we're already in the requested state.
393 * -EIO if device does not support PCI PM.
394 * 0 if we can successfully change the power state.
397 pci_set_power_state(struct pci_dev *dev, pci_power_t state)
399 int pm, need_restore = 0;
400 u16 pmcsr, pmc;
402 /* bound the state we're entering */
403 if (state > PCI_D3hot)
404 state = PCI_D3hot;
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 /* Validate current state:
422 * Can enter D0 from any state, but if we can only go deeper
423 * to sleep if we're already in a low power state
425 if (state != PCI_D0 && dev->current_state > state) {
426 printk(KERN_ERR "%s(): %s: state=%d, current state=%d\n",
427 __FUNCTION__, pci_name(dev), state, dev->current_state);
428 return -EINVAL;
429 } else if (dev->current_state == state)
430 return 0; /* we're already there */
433 pci_read_config_word(dev,pm + PCI_PM_PMC,&pmc);
434 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
435 printk(KERN_DEBUG
436 "PCI: %s has unsupported PM cap regs version (%u)\n",
437 pci_name(dev), pmc & PCI_PM_CAP_VER_MASK);
438 return -EIO;
441 /* check if this device supports the desired state */
442 if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
443 return -EIO;
444 else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2))
445 return -EIO;
447 pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
449 /* If we're (effectively) in D3, force entire word to 0.
450 * This doesn't affect PME_Status, disables PME_En, and
451 * sets PowerState to 0.
453 switch (dev->current_state) {
454 case PCI_D0:
455 case PCI_D1:
456 case PCI_D2:
457 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
458 pmcsr |= state;
459 break;
460 case PCI_UNKNOWN: /* Boot-up */
461 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
462 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
463 need_restore = 1;
464 /* Fall-through: force to D0 */
465 default:
466 pmcsr = 0;
467 break;
470 /* enter specified state */
471 pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
473 /* Mandatory power management transition delays */
474 /* see PCI PM 1.1 5.6.1 table 18 */
475 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
476 msleep(pci_pm_d3_delay);
477 else if (state == PCI_D2 || dev->current_state == PCI_D2)
478 udelay(200);
481 * Give firmware a chance to be called, such as ACPI _PRx, _PSx
482 * Firmware method after native method ?
484 if (platform_pci_set_power_state)
485 platform_pci_set_power_state(dev, state);
487 dev->current_state = state;
489 /* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
490 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
491 * from D3hot to D0 _may_ perform an internal reset, thereby
492 * going to "D0 Uninitialized" rather than "D0 Initialized".
493 * For example, at least some versions of the 3c905B and the
494 * 3c556B exhibit this behaviour.
496 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
497 * devices in a D3hot state at boot. Consequently, we need to
498 * restore at least the BARs so that the device will be
499 * accessible to its driver.
501 if (need_restore)
502 pci_restore_bars(dev);
504 return 0;
507 pci_power_t (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
510 * pci_choose_state - Choose the power state of a PCI device
511 * @dev: PCI device to be suspended
512 * @state: target sleep state for the whole system. This is the value
513 * that is passed to suspend() function.
515 * Returns PCI power state suitable for given device and given system
516 * message.
519 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
521 pci_power_t ret;
523 if (!pci_find_capability(dev, PCI_CAP_ID_PM))
524 return PCI_D0;
526 if (platform_pci_choose_state) {
527 ret = platform_pci_choose_state(dev, state);
528 if (ret != PCI_POWER_ERROR)
529 return ret;
532 switch (state.event) {
533 case PM_EVENT_ON:
534 return PCI_D0;
535 case PM_EVENT_FREEZE:
536 case PM_EVENT_PRETHAW:
537 /* REVISIT both freeze and pre-thaw "should" use D0 */
538 case PM_EVENT_SUSPEND:
539 return PCI_D3hot;
540 default:
541 printk("Unrecognized suspend event %d\n", state.event);
542 BUG();
544 return PCI_D0;
547 EXPORT_SYMBOL(pci_choose_state);
549 static int pci_save_pcie_state(struct pci_dev *dev)
551 int pos, i = 0;
552 struct pci_cap_saved_state *save_state;
553 u16 *cap;
555 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
556 if (pos <= 0)
557 return 0;
559 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
560 if (!save_state)
561 save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);
562 if (!save_state) {
563 dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
564 return -ENOMEM;
566 cap = (u16 *)&save_state->data[0];
568 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
569 pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
570 pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
571 pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
572 pci_add_saved_cap(dev, save_state);
573 return 0;
576 static void pci_restore_pcie_state(struct pci_dev *dev)
578 int i = 0, pos;
579 struct pci_cap_saved_state *save_state;
580 u16 *cap;
582 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
583 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
584 if (!save_state || pos <= 0)
585 return;
586 cap = (u16 *)&save_state->data[0];
588 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
589 pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
590 pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
591 pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
595 static int pci_save_pcix_state(struct pci_dev *dev)
597 int pos, i = 0;
598 struct pci_cap_saved_state *save_state;
599 u16 *cap;
601 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
602 if (pos <= 0)
603 return 0;
605 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
606 if (!save_state)
607 save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);
608 if (!save_state) {
609 dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
610 return -ENOMEM;
612 cap = (u16 *)&save_state->data[0];
614 pci_read_config_word(dev, pos + PCI_X_CMD, &cap[i++]);
615 pci_add_saved_cap(dev, save_state);
616 return 0;
619 static void pci_restore_pcix_state(struct pci_dev *dev)
621 int i = 0, pos;
622 struct pci_cap_saved_state *save_state;
623 u16 *cap;
625 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
626 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
627 if (!save_state || pos <= 0)
628 return;
629 cap = (u16 *)&save_state->data[0];
631 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
636 * pci_save_state - save the PCI configuration space of a device before suspending
637 * @dev: - PCI device that we're dealing with
640 pci_save_state(struct pci_dev *dev)
642 int i;
643 /* XXX: 100% dword access ok here? */
644 for (i = 0; i < 16; i++)
645 pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
646 if ((i = pci_save_pcie_state(dev)) != 0)
647 return i;
648 if ((i = pci_save_pcix_state(dev)) != 0)
649 return i;
650 return 0;
653 /**
654 * pci_restore_state - Restore the saved state of a PCI device
655 * @dev: - PCI device that we're dealing with
657 int
658 pci_restore_state(struct pci_dev *dev)
660 int i;
661 u32 val;
663 /* PCI Express register must be restored first */
664 pci_restore_pcie_state(dev);
667 * The Base Address register should be programmed before the command
668 * register(s)
670 for (i = 15; i >= 0; i--) {
671 pci_read_config_dword(dev, i * 4, &val);
672 if (val != dev->saved_config_space[i]) {
673 printk(KERN_DEBUG "PM: Writing back config space on "
674 "device %s at offset %x (was %x, writing %x)\n",
675 pci_name(dev), i,
676 val, (int)dev->saved_config_space[i]);
677 pci_write_config_dword(dev,i * 4,
678 dev->saved_config_space[i]);
681 pci_restore_pcix_state(dev);
682 pci_restore_msi_state(dev);
684 return 0;
687 static int do_pci_enable_device(struct pci_dev *dev, int bars)
689 int err;
691 err = pci_set_power_state(dev, PCI_D0);
692 if (err < 0 && err != -EIO)
693 return err;
694 err = pcibios_enable_device(dev, bars);
695 if (err < 0)
696 return err;
697 pci_fixup_device(pci_fixup_enable, dev);
699 return 0;
703 * pci_reenable_device - Resume abandoned device
704 * @dev: PCI device to be resumed
706 * Note this function is a backend of pci_default_resume and is not supposed
707 * to be called by normal code, write proper resume handler and use it instead.
709 int pci_reenable_device(struct pci_dev *dev)
711 if (atomic_read(&dev->enable_cnt))
712 return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
713 return 0;
717 * pci_enable_device_bars - Initialize some of a device for use
718 * @dev: PCI device to be initialized
719 * @bars: bitmask of BAR's that must be configured
721 * Initialize device before it's used by a driver. Ask low-level code
722 * to enable selected I/O and memory resources. Wake up the device if it
723 * was suspended. Beware, this function can fail.
726 pci_enable_device_bars(struct pci_dev *dev, int bars)
728 int err;
730 if (atomic_add_return(1, &dev->enable_cnt) > 1)
731 return 0; /* already enabled */
733 err = do_pci_enable_device(dev, bars);
734 if (err < 0)
735 atomic_dec(&dev->enable_cnt);
736 return err;
740 * pci_enable_device - Initialize device before it's used by a driver.
741 * @dev: PCI device to be initialized
743 * Initialize device before it's used by a driver. Ask low-level code
744 * to enable I/O and memory. Wake up the device if it was suspended.
745 * Beware, this function can fail.
747 * Note we don't actually enable the device many times if we call
748 * this function repeatedly (we just increment the count).
750 int pci_enable_device(struct pci_dev *dev)
752 return pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
756 * Managed PCI resources. This manages device on/off, intx/msi/msix
757 * on/off and BAR regions. pci_dev itself records msi/msix status, so
758 * there's no need to track it separately. pci_devres is initialized
759 * when a device is enabled using managed PCI device enable interface.
761 struct pci_devres {
762 unsigned int enabled:1;
763 unsigned int pinned:1;
764 unsigned int orig_intx:1;
765 unsigned int restore_intx:1;
766 u32 region_mask;
769 static void pcim_release(struct device *gendev, void *res)
771 struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
772 struct pci_devres *this = res;
773 int i;
775 if (dev->msi_enabled)
776 pci_disable_msi(dev);
777 if (dev->msix_enabled)
778 pci_disable_msix(dev);
780 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
781 if (this->region_mask & (1 << i))
782 pci_release_region(dev, i);
784 if (this->restore_intx)
785 pci_intx(dev, this->orig_intx);
787 if (this->enabled && !this->pinned)
788 pci_disable_device(dev);
791 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
793 struct pci_devres *dr, *new_dr;
795 dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
796 if (dr)
797 return dr;
799 new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
800 if (!new_dr)
801 return NULL;
802 return devres_get(&pdev->dev, new_dr, NULL, NULL);
805 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
807 if (pci_is_managed(pdev))
808 return devres_find(&pdev->dev, pcim_release, NULL, NULL);
809 return NULL;
813 * pcim_enable_device - Managed pci_enable_device()
814 * @pdev: PCI device to be initialized
816 * Managed pci_enable_device().
818 int pcim_enable_device(struct pci_dev *pdev)
820 struct pci_devres *dr;
821 int rc;
823 dr = get_pci_dr(pdev);
824 if (unlikely(!dr))
825 return -ENOMEM;
826 WARN_ON(!!dr->enabled);
828 rc = pci_enable_device(pdev);
829 if (!rc) {
830 pdev->is_managed = 1;
831 dr->enabled = 1;
833 return rc;
837 * pcim_pin_device - Pin managed PCI device
838 * @pdev: PCI device to pin
840 * Pin managed PCI device @pdev. Pinned device won't be disabled on
841 * driver detach. @pdev must have been enabled with
842 * pcim_enable_device().
844 void pcim_pin_device(struct pci_dev *pdev)
846 struct pci_devres *dr;
848 dr = find_pci_dr(pdev);
849 WARN_ON(!dr || !dr->enabled);
850 if (dr)
851 dr->pinned = 1;
855 * pcibios_disable_device - disable arch specific PCI resources for device dev
856 * @dev: the PCI device to disable
858 * Disables architecture specific PCI resources for the device. This
859 * is the default implementation. Architecture implementations can
860 * override this.
862 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
865 * pci_disable_device - Disable PCI device after use
866 * @dev: PCI device to be disabled
868 * Signal to the system that the PCI device is not in use by the system
869 * anymore. This only involves disabling PCI bus-mastering, if active.
871 * Note we don't actually disable the device until all callers of
872 * pci_device_enable() have called pci_device_disable().
874 void
875 pci_disable_device(struct pci_dev *dev)
877 struct pci_devres *dr;
878 u16 pci_command;
880 dr = find_pci_dr(dev);
881 if (dr)
882 dr->enabled = 0;
884 if (atomic_sub_return(1, &dev->enable_cnt) != 0)
885 return;
887 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
888 if (pci_command & PCI_COMMAND_MASTER) {
889 pci_command &= ~PCI_COMMAND_MASTER;
890 pci_write_config_word(dev, PCI_COMMAND, pci_command);
892 dev->is_busmaster = 0;
894 pcibios_disable_device(dev);
898 * pcibios_set_pcie_reset_state - set reset state for device dev
899 * @dev: the PCI-E device reset
900 * @state: Reset state to enter into
903 * Sets the PCI-E reset state for the device. This is the default
904 * implementation. Architecture implementations can override this.
906 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
907 enum pcie_reset_state state)
909 return -EINVAL;
913 * pci_set_pcie_reset_state - set reset state for device dev
914 * @dev: the PCI-E device reset
915 * @state: Reset state to enter into
918 * Sets the PCI reset state for the device.
920 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
922 return pcibios_set_pcie_reset_state(dev, state);
926 * pci_enable_wake - enable PCI device as wakeup event source
927 * @dev: PCI device affected
928 * @state: PCI state from which device will issue wakeup events
929 * @enable: True to enable event generation; false to disable
931 * This enables the device as a wakeup event source, or disables it.
932 * When such events involves platform-specific hooks, those hooks are
933 * called automatically by this routine.
935 * Devices with legacy power management (no standard PCI PM capabilities)
936 * always require such platform hooks. Depending on the platform, devices
937 * supporting the standard PCI PME# signal may require such platform hooks;
938 * they always update bits in config space to allow PME# generation.
940 * -EIO is returned if the device can't ever be a wakeup event source.
941 * -EINVAL is returned if the device can't generate wakeup events from
942 * the specified PCI state. Returns zero if the operation is successful.
944 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
946 int pm;
947 int status;
948 u16 value;
950 /* Note that drivers should verify device_may_wakeup(&dev->dev)
951 * before calling this function. Platform code should report
952 * errors when drivers try to enable wakeup on devices that
953 * can't issue wakeups, or on which wakeups were disabled by
954 * userspace updating the /sys/devices.../power/wakeup file.
957 status = call_platform_enable_wakeup(&dev->dev, enable);
959 /* find PCI PM capability in list */
960 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
962 /* If device doesn't support PM Capabilities, but caller wants to
963 * disable wake events, it's a NOP. Otherwise fail unless the
964 * platform hooks handled this legacy device already.
966 if (!pm)
967 return enable ? status : 0;
969 /* Check device's ability to generate PME# */
970 pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
972 value &= PCI_PM_CAP_PME_MASK;
973 value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */
975 /* Check if it can generate PME# from requested state. */
976 if (!value || !(value & (1 << state))) {
977 /* if it can't, revert what the platform hook changed,
978 * always reporting the base "EINVAL, can't PME#" error
980 if (enable)
981 call_platform_enable_wakeup(&dev->dev, 0);
982 return enable ? -EINVAL : 0;
985 pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
987 /* Clear PME_Status by writing 1 to it and enable PME# */
988 value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
990 if (!enable)
991 value &= ~PCI_PM_CTRL_PME_ENABLE;
993 pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
995 return 0;
999 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
1001 u8 pin;
1003 pin = dev->pin;
1004 if (!pin)
1005 return -1;
1006 pin--;
1007 while (dev->bus->self) {
1008 pin = (pin + PCI_SLOT(dev->devfn)) % 4;
1009 dev = dev->bus->self;
1011 *bridge = dev;
1012 return pin;
1016 * pci_release_region - Release a PCI bar
1017 * @pdev: PCI device whose resources were previously reserved by pci_request_region
1018 * @bar: BAR to release
1020 * Releases the PCI I/O and memory resources previously reserved by a
1021 * successful call to pci_request_region. Call this function only
1022 * after all use of the PCI regions has ceased.
1024 void pci_release_region(struct pci_dev *pdev, int bar)
1026 struct pci_devres *dr;
1028 if (pci_resource_len(pdev, bar) == 0)
1029 return;
1030 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1031 release_region(pci_resource_start(pdev, bar),
1032 pci_resource_len(pdev, bar));
1033 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1034 release_mem_region(pci_resource_start(pdev, bar),
1035 pci_resource_len(pdev, bar));
1037 dr = find_pci_dr(pdev);
1038 if (dr)
1039 dr->region_mask &= ~(1 << bar);
1043 * pci_request_region - Reserved PCI I/O and memory resource
1044 * @pdev: PCI device whose resources are to be reserved
1045 * @bar: BAR to be reserved
1046 * @res_name: Name to be associated with resource.
1048 * Mark the PCI region associated with PCI device @pdev BR @bar as
1049 * being reserved by owner @res_name. Do not access any
1050 * address inside the PCI regions unless this call returns
1051 * successfully.
1053 * Returns 0 on success, or %EBUSY on error. A warning
1054 * message is also printed on failure.
1056 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1058 struct pci_devres *dr;
1060 if (pci_resource_len(pdev, bar) == 0)
1061 return 0;
1063 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1064 if (!request_region(pci_resource_start(pdev, bar),
1065 pci_resource_len(pdev, bar), res_name))
1066 goto err_out;
1068 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1069 if (!request_mem_region(pci_resource_start(pdev, bar),
1070 pci_resource_len(pdev, bar), res_name))
1071 goto err_out;
1074 dr = find_pci_dr(pdev);
1075 if (dr)
1076 dr->region_mask |= 1 << bar;
1078 return 0;
1080 err_out:
1081 printk (KERN_WARNING "PCI: Unable to reserve %s region #%d:%llx@%llx "
1082 "for device %s\n",
1083 pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
1084 bar + 1, /* PCI BAR # */
1085 (unsigned long long)pci_resource_len(pdev, bar),
1086 (unsigned long long)pci_resource_start(pdev, bar),
1087 pci_name(pdev));
1088 return -EBUSY;
1092 * pci_release_selected_regions - Release selected PCI I/O and memory resources
1093 * @pdev: PCI device whose resources were previously reserved
1094 * @bars: Bitmask of BARs to be released
1096 * Release selected PCI I/O and memory resources previously reserved.
1097 * Call this function only after all use of the PCI regions has ceased.
1099 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1101 int i;
1103 for (i = 0; i < 6; i++)
1104 if (bars & (1 << i))
1105 pci_release_region(pdev, i);
1109 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
1110 * @pdev: PCI device whose resources are to be reserved
1111 * @bars: Bitmask of BARs to be requested
1112 * @res_name: Name to be associated with resource
1114 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
1115 const char *res_name)
1117 int i;
1119 for (i = 0; i < 6; i++)
1120 if (bars & (1 << i))
1121 if(pci_request_region(pdev, i, res_name))
1122 goto err_out;
1123 return 0;
1125 err_out:
1126 while(--i >= 0)
1127 if (bars & (1 << i))
1128 pci_release_region(pdev, i);
1130 return -EBUSY;
1134 * pci_release_regions - Release reserved PCI I/O and memory resources
1135 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
1137 * Releases all PCI I/O and memory resources previously reserved by a
1138 * successful call to pci_request_regions. Call this function only
1139 * after all use of the PCI regions has ceased.
1142 void pci_release_regions(struct pci_dev *pdev)
1144 pci_release_selected_regions(pdev, (1 << 6) - 1);
1148 * pci_request_regions - Reserved PCI I/O and memory resources
1149 * @pdev: PCI device whose resources are to be reserved
1150 * @res_name: Name to be associated with resource.
1152 * Mark all PCI regions associated with PCI device @pdev as
1153 * being reserved by owner @res_name. Do not access any
1154 * address inside the PCI regions unless this call returns
1155 * successfully.
1157 * Returns 0 on success, or %EBUSY on error. A warning
1158 * message is also printed on failure.
1160 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
1162 return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
1166 * pci_set_master - enables bus-mastering for device dev
1167 * @dev: the PCI device to enable
1169 * Enables bus-mastering on the device and calls pcibios_set_master()
1170 * to do the needed arch specific settings.
1172 void
1173 pci_set_master(struct pci_dev *dev)
1175 u16 cmd;
1177 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1178 if (! (cmd & PCI_COMMAND_MASTER)) {
1179 pr_debug("PCI: Enabling bus mastering for device %s\n", pci_name(dev));
1180 cmd |= PCI_COMMAND_MASTER;
1181 pci_write_config_word(dev, PCI_COMMAND, cmd);
1183 dev->is_busmaster = 1;
1184 pcibios_set_master(dev);
1187 #ifdef PCI_DISABLE_MWI
1188 int pci_set_mwi(struct pci_dev *dev)
1190 return 0;
1193 int pci_try_set_mwi(struct pci_dev *dev)
1195 return 0;
1198 void pci_clear_mwi(struct pci_dev *dev)
1202 #else
1204 #ifndef PCI_CACHE_LINE_BYTES
1205 #define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
1206 #endif
1208 /* This can be overridden by arch code. */
1209 /* Don't forget this is measured in 32-bit words, not bytes */
1210 u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
1213 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
1214 * @dev: the PCI device for which MWI is to be enabled
1216 * Helper function for pci_set_mwi.
1217 * Originally copied from drivers/net/acenic.c.
1218 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
1220 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1222 static int
1223 pci_set_cacheline_size(struct pci_dev *dev)
1225 u8 cacheline_size;
1227 if (!pci_cache_line_size)
1228 return -EINVAL; /* The system doesn't support MWI. */
1230 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
1231 equal to or multiple of the right value. */
1232 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1233 if (cacheline_size >= pci_cache_line_size &&
1234 (cacheline_size % pci_cache_line_size) == 0)
1235 return 0;
1237 /* Write the correct value. */
1238 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
1239 /* Read it back. */
1240 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
1241 if (cacheline_size == pci_cache_line_size)
1242 return 0;
1244 printk(KERN_DEBUG "PCI: cache line size of %d is not supported "
1245 "by device %s\n", pci_cache_line_size << 2, pci_name(dev));
1247 return -EINVAL;
1251 * pci_set_mwi - enables memory-write-invalidate PCI transaction
1252 * @dev: the PCI device for which MWI is enabled
1254 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1256 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1259 pci_set_mwi(struct pci_dev *dev)
1261 int rc;
1262 u16 cmd;
1264 rc = pci_set_cacheline_size(dev);
1265 if (rc)
1266 return rc;
1268 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1269 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
1270 pr_debug("PCI: Enabling Mem-Wr-Inval for device %s\n",
1271 pci_name(dev));
1272 cmd |= PCI_COMMAND_INVALIDATE;
1273 pci_write_config_word(dev, PCI_COMMAND, cmd);
1276 return 0;
1280 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
1281 * @dev: the PCI device for which MWI is enabled
1283 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
1284 * Callers are not required to check the return value.
1286 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1288 int pci_try_set_mwi(struct pci_dev *dev)
1290 int rc = pci_set_mwi(dev);
1291 return rc;
1295 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
1296 * @dev: the PCI device to disable
1298 * Disables PCI Memory-Write-Invalidate transaction on the device
1300 void
1301 pci_clear_mwi(struct pci_dev *dev)
1303 u16 cmd;
1305 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1306 if (cmd & PCI_COMMAND_INVALIDATE) {
1307 cmd &= ~PCI_COMMAND_INVALIDATE;
1308 pci_write_config_word(dev, PCI_COMMAND, cmd);
1311 #endif /* ! PCI_DISABLE_MWI */
1314 * pci_intx - enables/disables PCI INTx for device dev
1315 * @pdev: the PCI device to operate on
1316 * @enable: boolean: whether to enable or disable PCI INTx
1318 * Enables/disables PCI INTx for device dev
1320 void
1321 pci_intx(struct pci_dev *pdev, int enable)
1323 u16 pci_command, new;
1325 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
1327 if (enable) {
1328 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
1329 } else {
1330 new = pci_command | PCI_COMMAND_INTX_DISABLE;
1333 if (new != pci_command) {
1334 struct pci_devres *dr;
1336 pci_write_config_word(pdev, PCI_COMMAND, new);
1338 dr = find_pci_dr(pdev);
1339 if (dr && !dr->restore_intx) {
1340 dr->restore_intx = 1;
1341 dr->orig_intx = !enable;
1347 * pci_msi_off - disables any msi or msix capabilities
1348 * @dev: the PCI device to operate on
1350 * If you want to use msi see pci_enable_msi and friends.
1351 * This is a lower level primitive that allows us to disable
1352 * msi operation at the device level.
1354 void pci_msi_off(struct pci_dev *dev)
1356 int pos;
1357 u16 control;
1359 pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
1360 if (pos) {
1361 pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
1362 control &= ~PCI_MSI_FLAGS_ENABLE;
1363 pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
1365 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1366 if (pos) {
1367 pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
1368 control &= ~PCI_MSIX_FLAGS_ENABLE;
1369 pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
1373 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
1375 * These can be overridden by arch-specific implementations
1378 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
1380 if (!pci_dma_supported(dev, mask))
1381 return -EIO;
1383 dev->dma_mask = mask;
1385 return 0;
1389 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
1391 if (!pci_dma_supported(dev, mask))
1392 return -EIO;
1394 dev->dev.coherent_dma_mask = mask;
1396 return 0;
1398 #endif
1401 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
1402 * @dev: PCI device to query
1404 * Returns mmrbc: maximum designed memory read count in bytes
1405 * or appropriate error value.
1407 int pcix_get_max_mmrbc(struct pci_dev *dev)
1409 int err, cap;
1410 u32 stat;
1412 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1413 if (!cap)
1414 return -EINVAL;
1416 err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
1417 if (err)
1418 return -EINVAL;
1420 return (stat & PCI_X_STATUS_MAX_READ) >> 12;
1422 EXPORT_SYMBOL(pcix_get_max_mmrbc);
1425 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
1426 * @dev: PCI device to query
1428 * Returns mmrbc: maximum memory read count in bytes
1429 * or appropriate error value.
1431 int pcix_get_mmrbc(struct pci_dev *dev)
1433 int ret, cap;
1434 u32 cmd;
1436 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1437 if (!cap)
1438 return -EINVAL;
1440 ret = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
1441 if (!ret)
1442 ret = 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
1444 return ret;
1446 EXPORT_SYMBOL(pcix_get_mmrbc);
1449 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
1450 * @dev: PCI device to query
1451 * @mmrbc: maximum memory read count in bytes
1452 * valid values are 512, 1024, 2048, 4096
1454 * If possible sets maximum memory read byte count, some bridges have erratas
1455 * that prevent this.
1457 int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
1459 int cap, err = -EINVAL;
1460 u32 stat, cmd, v, o;
1462 if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
1463 goto out;
1465 v = ffs(mmrbc) - 10;
1467 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1468 if (!cap)
1469 goto out;
1471 err = pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat);
1472 if (err)
1473 goto out;
1475 if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
1476 return -E2BIG;
1478 err = pci_read_config_dword(dev, cap + PCI_X_CMD, &cmd);
1479 if (err)
1480 goto out;
1482 o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
1483 if (o != v) {
1484 if (v > o && dev->bus &&
1485 (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
1486 return -EIO;
1488 cmd &= ~PCI_X_CMD_MAX_READ;
1489 cmd |= v << 2;
1490 err = pci_write_config_dword(dev, cap + PCI_X_CMD, cmd);
1492 out:
1493 return err;
1495 EXPORT_SYMBOL(pcix_set_mmrbc);
1498 * pcie_get_readrq - get PCI Express read request size
1499 * @dev: PCI device to query
1501 * Returns maximum memory read request in bytes
1502 * or appropriate error value.
1504 int pcie_get_readrq(struct pci_dev *dev)
1506 int ret, cap;
1507 u16 ctl;
1509 cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
1510 if (!cap)
1511 return -EINVAL;
1513 ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
1514 if (!ret)
1515 ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
1517 return ret;
1519 EXPORT_SYMBOL(pcie_get_readrq);
1522 * pcie_set_readrq - set PCI Express maximum memory read request
1523 * @dev: PCI device to query
1524 * @rq: maximum memory read count in bytes
1525 * valid values are 128, 256, 512, 1024, 2048, 4096
1527 * If possible sets maximum read byte count
1529 int pcie_set_readrq(struct pci_dev *dev, int rq)
1531 int cap, err = -EINVAL;
1532 u16 ctl, v;
1534 if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
1535 goto out;
1537 v = (ffs(rq) - 8) << 12;
1539 cap = pci_find_capability(dev, PCI_CAP_ID_EXP);
1540 if (!cap)
1541 goto out;
1543 err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
1544 if (err)
1545 goto out;
1547 if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
1548 ctl &= ~PCI_EXP_DEVCTL_READRQ;
1549 ctl |= v;
1550 err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
1553 out:
1554 return err;
1556 EXPORT_SYMBOL(pcie_set_readrq);
1559 * pci_select_bars - Make BAR mask from the type of resource
1560 * @dev: the PCI device for which BAR mask is made
1561 * @flags: resource type mask to be selected
1563 * This helper routine makes bar mask from the type of resource.
1565 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
1567 int i, bars = 0;
1568 for (i = 0; i < PCI_NUM_RESOURCES; i++)
1569 if (pci_resource_flags(dev, i) & flags)
1570 bars |= (1 << i);
1571 return bars;
1574 static void __devinit pci_no_domains(void)
1576 #ifdef CONFIG_PCI_DOMAINS
1577 pci_domains_supported = 0;
1578 #endif
1581 static int __devinit pci_init(void)
1583 struct pci_dev *dev = NULL;
1585 while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
1586 pci_fixup_device(pci_fixup_final, dev);
1588 return 0;
1591 static int __devinit pci_setup(char *str)
1593 while (str) {
1594 char *k = strchr(str, ',');
1595 if (k)
1596 *k++ = 0;
1597 if (*str && (str = pcibios_setup(str)) && *str) {
1598 if (!strcmp(str, "nomsi")) {
1599 pci_no_msi();
1600 } else if (!strcmp(str, "noaer")) {
1601 pci_no_aer();
1602 } else if (!strcmp(str, "nodomains")) {
1603 pci_no_domains();
1604 } else if (!strncmp(str, "cbiosize=", 9)) {
1605 pci_cardbus_io_size = memparse(str + 9, &str);
1606 } else if (!strncmp(str, "cbmemsize=", 10)) {
1607 pci_cardbus_mem_size = memparse(str + 10, &str);
1608 } else {
1609 printk(KERN_ERR "PCI: Unknown option `%s'\n",
1610 str);
1613 str = k;
1615 return 0;
1617 early_param("pci", pci_setup);
1619 device_initcall(pci_init);
1621 EXPORT_SYMBOL_GPL(pci_restore_bars);
1622 EXPORT_SYMBOL(pci_reenable_device);
1623 EXPORT_SYMBOL(pci_enable_device_bars);
1624 EXPORT_SYMBOL(pci_enable_device);
1625 EXPORT_SYMBOL(pcim_enable_device);
1626 EXPORT_SYMBOL(pcim_pin_device);
1627 EXPORT_SYMBOL(pci_disable_device);
1628 EXPORT_SYMBOL(pci_find_capability);
1629 EXPORT_SYMBOL(pci_bus_find_capability);
1630 EXPORT_SYMBOL(pci_release_regions);
1631 EXPORT_SYMBOL(pci_request_regions);
1632 EXPORT_SYMBOL(pci_release_region);
1633 EXPORT_SYMBOL(pci_request_region);
1634 EXPORT_SYMBOL(pci_release_selected_regions);
1635 EXPORT_SYMBOL(pci_request_selected_regions);
1636 EXPORT_SYMBOL(pci_set_master);
1637 EXPORT_SYMBOL(pci_set_mwi);
1638 EXPORT_SYMBOL(pci_try_set_mwi);
1639 EXPORT_SYMBOL(pci_clear_mwi);
1640 EXPORT_SYMBOL_GPL(pci_intx);
1641 EXPORT_SYMBOL(pci_set_dma_mask);
1642 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
1643 EXPORT_SYMBOL(pci_assign_resource);
1644 EXPORT_SYMBOL(pci_find_parent_resource);
1645 EXPORT_SYMBOL(pci_select_bars);
1647 EXPORT_SYMBOL(pci_set_power_state);
1648 EXPORT_SYMBOL(pci_save_state);
1649 EXPORT_SYMBOL(pci_restore_state);
1650 EXPORT_SYMBOL(pci_enable_wake);
1651 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);