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1 /*
2 * $Id: pci.c,v 1.91 1999/01/21 13:34:01 davem Exp $
3 *
4 * PCI Bus Services, see include/linux/pci.h for further explanation.
5 *
6 * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
7 * David Mosberger-Tang
8 *
9 * Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
10 */
11
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"
21
22
23 /**
24 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
25 * @bus: pointer to PCI bus structure to search
26 *
27 * Given a PCI bus, returns the highest PCI bus number present in the set
28 * including the given PCI bus and its list of child PCI buses.
29 */
30 unsigned char __devinit
31 pci_bus_max_busnr(struct pci_bus* bus)
32 {
33 struct list_head *tmp;
34 unsigned char max, n;
35
36 max = bus->subordinate;
37 list_for_each(tmp, &bus->children) {
38 n = pci_bus_max_busnr(pci_bus_b(tmp));
39 if(n > max)
40 max = n;
41 }
42 return max;
43 }
44 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
45
46 #if 0
47 /**
48 * pci_max_busnr - returns maximum PCI bus number
49 *
50 * Returns the highest PCI bus number present in the system global list of
51 * PCI buses.
52 */
53 unsigned char __devinit
54 pci_max_busnr(void)
55 {
56 struct pci_bus *bus = NULL;
57 unsigned char max, n;
58
59 max = 0;
60 while ((bus = pci_find_next_bus(bus)) != NULL) {
61 n = pci_bus_max_busnr(bus);
62 if(n > max)
63 max = n;
64 }
65 return max;
66 }
67
68 #endif /* 0 */
69
70 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn, u8 pos, int cap)
71 {
72 u8 id;
73 int ttl = 48;
74
75 while (ttl--) {
76 pci_bus_read_config_byte(bus, devfn, pos, &pos);
77 if (pos < 0x40)
78 break;
79 pos &= ~3;
80 pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
81 &id);
82 if (id == 0xff)
83 break;
84 if (id == cap)
85 return pos;
86 pos += PCI_CAP_LIST_NEXT;
87 }
88 return 0;
89 }
90
91 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
92 {
93 return __pci_find_next_cap(dev->bus, dev->devfn,
94 pos + PCI_CAP_LIST_NEXT, cap);
95 }
96 EXPORT_SYMBOL_GPL(pci_find_next_capability);
97
98 static int __pci_bus_find_cap(struct pci_bus *bus, unsigned int devfn, u8 hdr_type, int cap)
99 {
100 u16 status;
101 u8 pos;
102
103 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
104 if (!(status & PCI_STATUS_CAP_LIST))
105 return 0;
106
107 switch (hdr_type) {
108 case PCI_HEADER_TYPE_NORMAL:
109 case PCI_HEADER_TYPE_BRIDGE:
110 pos = PCI_CAPABILITY_LIST;
111 break;
112 case PCI_HEADER_TYPE_CARDBUS:
113 pos = PCI_CB_CAPABILITY_LIST;
114 break;
115 default:
116 return 0;
117 }
118 return __pci_find_next_cap(bus, devfn, pos, cap);
119 }
120
121 /**
122 * pci_find_capability - query for devices' capabilities
123 * @dev: PCI device to query
124 * @cap: capability code
125 *
126 * Tell if a device supports a given PCI capability.
127 * Returns the address of the requested capability structure within the
128 * device's PCI configuration space or 0 in case the device does not
129 * support it. Possible values for @cap:
130 *
131 * %PCI_CAP_ID_PM Power Management
132 * %PCI_CAP_ID_AGP Accelerated Graphics Port
133 * %PCI_CAP_ID_VPD Vital Product Data
134 * %PCI_CAP_ID_SLOTID Slot Identification
135 * %PCI_CAP_ID_MSI Message Signalled Interrupts
136 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
137 * %PCI_CAP_ID_PCIX PCI-X
138 * %PCI_CAP_ID_EXP PCI Express
139 */
140 int pci_find_capability(struct pci_dev *dev, int cap)
141 {
142 return __pci_bus_find_cap(dev->bus, dev->devfn, dev->hdr_type, cap);
143 }
144
145 /**
146 * pci_bus_find_capability - query for devices' capabilities
147 * @bus: the PCI bus to query
148 * @devfn: PCI device to query
149 * @cap: capability code
150 *
151 * Like pci_find_capability() but works for pci devices that do not have a
152 * pci_dev structure set up yet.
153 *
154 * Returns the address of the requested capability structure within the
155 * device's PCI configuration space or 0 in case the device does not
156 * support it.
157 */
158 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
159 {
160 u8 hdr_type;
161
162 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
163
164 return __pci_bus_find_cap(bus, devfn, hdr_type & 0x7f, cap);
165 }
166
167 #if 0
168 /**
169 * pci_find_ext_capability - Find an extended capability
170 * @dev: PCI device to query
171 * @cap: capability code
172 *
173 * Returns the address of the requested extended capability structure
174 * within the device's PCI configuration space or 0 if the device does
175 * not support it. Possible values for @cap:
176 *
177 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
178 * %PCI_EXT_CAP_ID_VC Virtual Channel
179 * %PCI_EXT_CAP_ID_DSN Device Serial Number
180 * %PCI_EXT_CAP_ID_PWR Power Budgeting
181 */
182 int pci_find_ext_capability(struct pci_dev *dev, int cap)
183 {
184 u32 header;
185 int ttl = 480; /* 3840 bytes, minimum 8 bytes per capability */
186 int pos = 0x100;
187
188 if (dev->cfg_size <= 256)
189 return 0;
190
191 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
192 return 0;
193
194 /*
195 * If we have no capabilities, this is indicated by cap ID,
196 * cap version and next pointer all being 0.
197 */
198 if (header == 0)
199 return 0;
200
201 while (ttl-- > 0) {
202 if (PCI_EXT_CAP_ID(header) == cap)
203 return pos;
204
205 pos = PCI_EXT_CAP_NEXT(header);
206 if (pos < 0x100)
207 break;
208
209 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
210 break;
211 }
212
213 return 0;
214 }
215 #endif /* 0 */
216
217 /**
218 * pci_find_parent_resource - return resource region of parent bus of given region
219 * @dev: PCI device structure contains resources to be searched
220 * @res: child resource record for which parent is sought
221 *
222 * For given resource region of given device, return the resource
223 * region of parent bus the given region is contained in or where
224 * it should be allocated from.
225 */
226 struct resource *
227 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
228 {
229 const struct pci_bus *bus = dev->bus;
230 int i;
231 struct resource *best = NULL;
232
233 for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
234 struct resource *r = bus->resource[i];
235 if (!r)
236 continue;
237 if (res->start && !(res->start >= r->start && res->end <= r->end))
238 continue; /* Not contained */
239 if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
240 continue; /* Wrong type */
241 if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
242 return r; /* Exact match */
243 if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
244 best = r; /* Approximating prefetchable by non-prefetchable */
245 }
246 return best;
247 }
248
249 /**
250 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
251 * @dev: PCI device to have its BARs restored
252 *
253 * Restore the BAR values for a given device, so as to make it
254 * accessible by its driver.
255 */
256 void
257 pci_restore_bars(struct pci_dev *dev)
258 {
259 int i, numres;
260
261 switch (dev->hdr_type) {
262 case PCI_HEADER_TYPE_NORMAL:
263 numres = 6;
264 break;
265 case PCI_HEADER_TYPE_BRIDGE:
266 numres = 2;
267 break;
268 case PCI_HEADER_TYPE_CARDBUS:
269 numres = 1;
270 break;
271 default:
272 /* Should never get here, but just in case... */
273 return;
274 }
275
276 for (i = 0; i < numres; i ++)
277 pci_update_resource(dev, &dev->resource[i], i);
278 }
279
280 int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t t);
281
282 /**
283 * pci_set_power_state - Set the power state of a PCI device
284 * @dev: PCI device to be suspended
285 * @state: PCI power state (D0, D1, D2, D3hot, D3cold) we're entering
286 *
287 * Transition a device to a new power state, using the Power Management
288 * Capabilities in the device's config space.
289 *
290 * RETURN VALUE:
291 * -EINVAL if trying to enter a lower state than we're already in.
292 * 0 if we're already in the requested state.
293 * -EIO if device does not support PCI PM.
294 * 0 if we can successfully change the power state.
295 */
296 int
297 pci_set_power_state(struct pci_dev *dev, pci_power_t state)
298 {
299 int pm, need_restore = 0;
300 u16 pmcsr, pmc;
301
302 /* bound the state we're entering */
303 if (state > PCI_D3hot)
304 state = PCI_D3hot;
305
306 /* Validate current state:
307 * Can enter D0 from any state, but if we can only go deeper
308 * to sleep if we're already in a low power state
309 */
310 if (state != PCI_D0 && dev->current_state > state)
311 return -EINVAL;
312 else if (dev->current_state == state)
313 return 0; /* we're already there */
314
315 /* find PCI PM capability in list */
316 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
317
318 /* abort if the device doesn't support PM capabilities */
319 if (!pm)
320 return -EIO;
321
322 pci_read_config_word(dev,pm + PCI_PM_PMC,&pmc);
323 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
324 printk(KERN_DEBUG
325 "PCI: %s has unsupported PM cap regs version (%u)\n",
326 pci_name(dev), pmc & PCI_PM_CAP_VER_MASK);
327 return -EIO;
328 }
329
330 /* check if this device supports the desired state */
331 if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
332 return -EIO;
333 else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2))
334 return -EIO;
335
336 pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
337
338 /* If we're (effectively) in D3, force entire word to 0.
339 * This doesn't affect PME_Status, disables PME_En, and
340 * sets PowerState to 0.
341 */
342 switch (dev->current_state) {
343 case PCI_D0:
344 case PCI_D1:
345 case PCI_D2:
346 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
347 pmcsr |= state;
348 break;
349 case PCI_UNKNOWN: /* Boot-up */
350 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
351 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
352 need_restore = 1;
353 /* Fall-through: force to D0 */
354 default:
355 pmcsr = 0;
356 break;
357 }
358
359 /* enter specified state */
360 pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
361
362 /* Mandatory power management transition delays */
363 /* see PCI PM 1.1 5.6.1 table 18 */
364 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
365 msleep(10);
366 else if (state == PCI_D2 || dev->current_state == PCI_D2)
367 udelay(200);
368
369 /*
370 * Give firmware a chance to be called, such as ACPI _PRx, _PSx
371 * Firmware method after natice method ?
372 */
373 if (platform_pci_set_power_state)
374 platform_pci_set_power_state(dev, state);
375
376 dev->current_state = state;
377
378 /* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
379 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
380 * from D3hot to D0 _may_ perform an internal reset, thereby
381 * going to "D0 Uninitialized" rather than "D0 Initialized".
382 * For example, at least some versions of the 3c905B and the
383 * 3c556B exhibit this behaviour.
384 *
385 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
386 * devices in a D3hot state at boot. Consequently, we need to
387 * restore at least the BARs so that the device will be
388 * accessible to its driver.
389 */
390 if (need_restore)
391 pci_restore_bars(dev);
392
393 return 0;
394 }
395
396 int (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
397
398 /**
399 * pci_choose_state - Choose the power state of a PCI device
400 * @dev: PCI device to be suspended
401 * @state: target sleep state for the whole system. This is the value
402 * that is passed to suspend() function.
403 *
404 * Returns PCI power state suitable for given device and given system
405 * message.
406 */
407
408 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
409 {
410 int ret;
411
412 if (!pci_find_capability(dev, PCI_CAP_ID_PM))
413 return PCI_D0;
414
415 if (platform_pci_choose_state) {
416 ret = platform_pci_choose_state(dev, state);
417 if (ret >= 0)
418 state.event = ret;
419 }
420
421 switch (state.event) {
422 case PM_EVENT_ON:
423 return PCI_D0;
424 case PM_EVENT_FREEZE:
425 case PM_EVENT_SUSPEND:
426 return PCI_D3hot;
427 default:
428 printk("They asked me for state %d\n", state.event);
429 BUG();
430 }
431 return PCI_D0;
432 }
433
434 EXPORT_SYMBOL(pci_choose_state);
435
436 /**
437 * pci_save_state - save the PCI configuration space of a device before suspending
438 * @dev: - PCI device that we're dealing with
439 */
440 int
441 pci_save_state(struct pci_dev *dev)
442 {
443 int i;
444 /* XXX: 100% dword access ok here? */
445 for (i = 0; i < 16; i++)
446 pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
447 return 0;
448 }
449
450 /**
451 * pci_restore_state - Restore the saved state of a PCI device
452 * @dev: - PCI device that we're dealing with
453 */
454 int
455 pci_restore_state(struct pci_dev *dev)
456 {
457 int i;
458
459 for (i = 0; i < 16; i++)
460 pci_write_config_dword(dev,i * 4, dev->saved_config_space[i]);
461 return 0;
462 }
463
464 /**
465 * pci_enable_device_bars - Initialize some of a device for use
466 * @dev: PCI device to be initialized
467 * @bars: bitmask of BAR's that must be configured
468 *
469 * Initialize device before it's used by a driver. Ask low-level code
470 * to enable selected I/O and memory resources. Wake up the device if it
471 * was suspended. Beware, this function can fail.
472 */
473
474 int
475 pci_enable_device_bars(struct pci_dev *dev, int bars)
476 {
477 int err;
478
479 err = pci_set_power_state(dev, PCI_D0);
480 if (err < 0 && err != -EIO)
481 return err;
482 err = pcibios_enable_device(dev, bars);
483 if (err < 0)
484 return err;
485 return 0;
486 }
487
488 /**
489 * pci_enable_device - Initialize device before it's used by a driver.
490 * @dev: PCI device to be initialized
491 *
492 * Initialize device before it's used by a driver. Ask low-level code
493 * to enable I/O and memory. Wake up the device if it was suspended.
494 * Beware, this function can fail.
495 */
496 int
497 pci_enable_device(struct pci_dev *dev)
498 {
499 int err = pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
500 if (err)
501 return err;
502 pci_fixup_device(pci_fixup_enable, dev);
503 dev->is_enabled = 1;
504 return 0;
505 }
506
507 /**
508 * pcibios_disable_device - disable arch specific PCI resources for device dev
509 * @dev: the PCI device to disable
510 *
511 * Disables architecture specific PCI resources for the device. This
512 * is the default implementation. Architecture implementations can
513 * override this.
514 */
515 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
516
517 /**
518 * pci_disable_device - Disable PCI device after use
519 * @dev: PCI device to be disabled
520 *
521 * Signal to the system that the PCI device is not in use by the system
522 * anymore. This only involves disabling PCI bus-mastering, if active.
523 */
524 void
525 pci_disable_device(struct pci_dev *dev)
526 {
527 u16 pci_command;
528
529 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
530 if (pci_command & PCI_COMMAND_MASTER) {
531 pci_command &= ~PCI_COMMAND_MASTER;
532 pci_write_config_word(dev, PCI_COMMAND, pci_command);
533 }
534 dev->is_busmaster = 0;
535
536 pcibios_disable_device(dev);
537 dev->is_enabled = 0;
538 }
539
540 /**
541 * pci_enable_wake - enable device to generate PME# when suspended
542 * @dev: - PCI device to operate on
543 * @state: - Current state of device.
544 * @enable: - Flag to enable or disable generation
545 *
546 * Set the bits in the device's PM Capabilities to generate PME# when
547 * the system is suspended.
548 *
549 * -EIO is returned if device doesn't have PM Capabilities.
550 * -EINVAL is returned if device supports it, but can't generate wake events.
551 * 0 if operation is successful.
552 *
553 */
554 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
555 {
556 int pm;
557 u16 value;
558
559 /* find PCI PM capability in list */
560 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
561
562 /* If device doesn't support PM Capabilities, but request is to disable
563 * wake events, it's a nop; otherwise fail */
564 if (!pm)
565 return enable ? -EIO : 0;
566
567 /* Check device's ability to generate PME# */
568 pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
569
570 value &= PCI_PM_CAP_PME_MASK;
571 value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */
572
573 /* Check if it can generate PME# from requested state. */
574 if (!value || !(value & (1 << state)))
575 return enable ? -EINVAL : 0;
576
577 pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
578
579 /* Clear PME_Status by writing 1 to it and enable PME# */
580 value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
581
582 if (!enable)
583 value &= ~PCI_PM_CTRL_PME_ENABLE;
584
585 pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
586
587 return 0;
588 }
589
590 int
591 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
592 {
593 u8 pin;
594
595 pin = dev->pin;
596 if (!pin)
597 return -1;
598 pin--;
599 while (dev->bus->self) {
600 pin = (pin + PCI_SLOT(dev->devfn)) % 4;
601 dev = dev->bus->self;
602 }
603 *bridge = dev;
604 return pin;
605 }
606
607 /**
608 * pci_release_region - Release a PCI bar
609 * @pdev: PCI device whose resources were previously reserved by pci_request_region
610 * @bar: BAR to release
611 *
612 * Releases the PCI I/O and memory resources previously reserved by a
613 * successful call to pci_request_region. Call this function only
614 * after all use of the PCI regions has ceased.
615 */
616 void pci_release_region(struct pci_dev *pdev, int bar)
617 {
618 if (pci_resource_len(pdev, bar) == 0)
619 return;
620 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
621 release_region(pci_resource_start(pdev, bar),
622 pci_resource_len(pdev, bar));
623 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
624 release_mem_region(pci_resource_start(pdev, bar),
625 pci_resource_len(pdev, bar));
626 }
627
628 /**
629 * pci_request_region - Reserved PCI I/O and memory resource
630 * @pdev: PCI device whose resources are to be reserved
631 * @bar: BAR to be reserved
632 * @res_name: Name to be associated with resource.
633 *
634 * Mark the PCI region associated with PCI device @pdev BR @bar as
635 * being reserved by owner @res_name. Do not access any
636 * address inside the PCI regions unless this call returns
637 * successfully.
638 *
639 * Returns 0 on success, or %EBUSY on error. A warning
640 * message is also printed on failure.
641 */
642 int pci_request_region(struct pci_dev *pdev, int bar, char *res_name)
643 {
644 if (pci_resource_len(pdev, bar) == 0)
645 return 0;
646
647 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
648 if (!request_region(pci_resource_start(pdev, bar),
649 pci_resource_len(pdev, bar), res_name))
650 goto err_out;
651 }
652 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
653 if (!request_mem_region(pci_resource_start(pdev, bar),
654 pci_resource_len(pdev, bar), res_name))
655 goto err_out;
656 }
657
658 return 0;
659
660 err_out:
661 printk (KERN_WARNING "PCI: Unable to reserve %s region #%d:%lx@%lx for device %s\n",
662 pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
663 bar + 1, /* PCI BAR # */
664 pci_resource_len(pdev, bar), pci_resource_start(pdev, bar),
665 pci_name(pdev));
666 return -EBUSY;
667 }
668
669
670 /**
671 * pci_release_regions - Release reserved PCI I/O and memory resources
672 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
673 *
674 * Releases all PCI I/O and memory resources previously reserved by a
675 * successful call to pci_request_regions. Call this function only
676 * after all use of the PCI regions has ceased.
677 */
678
679 void pci_release_regions(struct pci_dev *pdev)
680 {
681 int i;
682
683 for (i = 0; i < 6; i++)
684 pci_release_region(pdev, i);
685 }
686
687 /**
688 * pci_request_regions - Reserved PCI I/O and memory resources
689 * @pdev: PCI device whose resources are to be reserved
690 * @res_name: Name to be associated with resource.
691 *
692 * Mark all PCI regions associated with PCI device @pdev as
693 * being reserved by owner @res_name. Do not access any
694 * address inside the PCI regions unless this call returns
695 * successfully.
696 *
697 * Returns 0 on success, or %EBUSY on error. A warning
698 * message is also printed on failure.
699 */
700 int pci_request_regions(struct pci_dev *pdev, char *res_name)
701 {
702 int i;
703
704 for (i = 0; i < 6; i++)
705 if(pci_request_region(pdev, i, res_name))
706 goto err_out;
707 return 0;
708
709 err_out:
710 while(--i >= 0)
711 pci_release_region(pdev, i);
712
713 return -EBUSY;
714 }
715
716 /**
717 * pci_set_master - enables bus-mastering for device dev
718 * @dev: the PCI device to enable
719 *
720 * Enables bus-mastering on the device and calls pcibios_set_master()
721 * to do the needed arch specific settings.
722 */
723 void
724 pci_set_master(struct pci_dev *dev)
725 {
726 u16 cmd;
727
728 pci_read_config_word(dev, PCI_COMMAND, &cmd);
729 if (! (cmd & PCI_COMMAND_MASTER)) {
730 pr_debug("PCI: Enabling bus mastering for device %s\n", pci_name(dev));
731 cmd |= PCI_COMMAND_MASTER;
732 pci_write_config_word(dev, PCI_COMMAND, cmd);
733 }
734 dev->is_busmaster = 1;
735 pcibios_set_master(dev);
736 }
737
738 #ifndef HAVE_ARCH_PCI_MWI
739 /* This can be overridden by arch code. */
740 u8 pci_cache_line_size = L1_CACHE_BYTES >> 2;
741
742 /**
743 * pci_generic_prep_mwi - helper function for pci_set_mwi
744 * @dev: the PCI device for which MWI is enabled
745 *
746 * Helper function for generic implementation of pcibios_prep_mwi
747 * function. Originally copied from drivers/net/acenic.c.
748 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
749 *
750 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
751 */
752 static int
753 pci_generic_prep_mwi(struct pci_dev *dev)
754 {
755 u8 cacheline_size;
756
757 if (!pci_cache_line_size)
758 return -EINVAL; /* The system doesn't support MWI. */
759
760 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
761 equal to or multiple of the right value. */
762 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
763 if (cacheline_size >= pci_cache_line_size &&
764 (cacheline_size % pci_cache_line_size) == 0)
765 return 0;
766
767 /* Write the correct value. */
768 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
769 /* Read it back. */
770 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
771 if (cacheline_size == pci_cache_line_size)
772 return 0;
773
774 printk(KERN_DEBUG "PCI: cache line size of %d is not supported "
775 "by device %s\n", pci_cache_line_size << 2, pci_name(dev));
776
777 return -EINVAL;
778 }
779 #endif /* !HAVE_ARCH_PCI_MWI */
780
781 /**
782 * pci_set_mwi - enables memory-write-invalidate PCI transaction
783 * @dev: the PCI device for which MWI is enabled
784 *
785 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND,
786 * and then calls @pcibios_set_mwi to do the needed arch specific
787 * operations or a generic mwi-prep function.
788 *
789 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
790 */
791 int
792 pci_set_mwi(struct pci_dev *dev)
793 {
794 int rc;
795 u16 cmd;
796
797 #ifdef HAVE_ARCH_PCI_MWI
798 rc = pcibios_prep_mwi(dev);
799 #else
800 rc = pci_generic_prep_mwi(dev);
801 #endif
802
803 if (rc)
804 return rc;
805
806 pci_read_config_word(dev, PCI_COMMAND, &cmd);
807 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
808 pr_debug("PCI: Enabling Mem-Wr-Inval for device %s\n", pci_name(dev));
809 cmd |= PCI_COMMAND_INVALIDATE;
810 pci_write_config_word(dev, PCI_COMMAND, cmd);
811 }
812
813 return 0;
814 }
815
816 /**
817 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
818 * @dev: the PCI device to disable
819 *
820 * Disables PCI Memory-Write-Invalidate transaction on the device
821 */
822 void
823 pci_clear_mwi(struct pci_dev *dev)
824 {
825 u16 cmd;
826
827 pci_read_config_word(dev, PCI_COMMAND, &cmd);
828 if (cmd & PCI_COMMAND_INVALIDATE) {
829 cmd &= ~PCI_COMMAND_INVALIDATE;
830 pci_write_config_word(dev, PCI_COMMAND, cmd);
831 }
832 }
833
834 /**
835 * pci_intx - enables/disables PCI INTx for device dev
836 * @pdev: the PCI device to operate on
837 * @enable: boolean: whether to enable or disable PCI INTx
838 *
839 * Enables/disables PCI INTx for device dev
840 */
841 void
842 pci_intx(struct pci_dev *pdev, int enable)
843 {
844 u16 pci_command, new;
845
846 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
847
848 if (enable) {
849 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
850 } else {
851 new = pci_command | PCI_COMMAND_INTX_DISABLE;
852 }
853
854 if (new != pci_command) {
855 pci_write_config_word(pdev, PCI_COMMAND, new);
856 }
857 }
858
859 #ifndef HAVE_ARCH_PCI_SET_DMA_MASK
860 /*
861 * These can be overridden by arch-specific implementations
862 */
863 int
864 pci_set_dma_mask(struct pci_dev *dev, u64 mask)
865 {
866 if (!pci_dma_supported(dev, mask))
867 return -EIO;
868
869 dev->dma_mask = mask;
870
871 return 0;
872 }
873
874 int
875 pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
876 {
877 if (!pci_dma_supported(dev, mask))
878 return -EIO;
879
880 dev->dev.coherent_dma_mask = mask;
881
882 return 0;
883 }
884 #endif
885
886 static int __devinit pci_init(void)
887 {
888 struct pci_dev *dev = NULL;
889
890 while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
891 pci_fixup_device(pci_fixup_final, dev);
892 }
893 return 0;
894 }
895
896 static int __devinit pci_setup(char *str)
897 {
898 while (str) {
899 char *k = strchr(str, ',');
900 if (k)
901 *k++ = 0;
902 if (*str && (str = pcibios_setup(str)) && *str) {
903 /* PCI layer options should be handled here */
904 printk(KERN_ERR "PCI: Unknown option `%s'\n", str);
905 }
906 str = k;
907 }
908 return 1;
909 }
910
911 device_initcall(pci_init);
912
913 __setup("pci=", pci_setup);
914
915 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
916 /* FIXME: Some boxes have multiple ISA bridges! */
917 struct pci_dev *isa_bridge;
918 EXPORT_SYMBOL(isa_bridge);
919 #endif
920
921 EXPORT_SYMBOL_GPL(pci_restore_bars);
922 EXPORT_SYMBOL(pci_enable_device_bars);
923 EXPORT_SYMBOL(pci_enable_device);
924 EXPORT_SYMBOL(pci_disable_device);
925 EXPORT_SYMBOL(pci_find_capability);
926 EXPORT_SYMBOL(pci_bus_find_capability);
927 EXPORT_SYMBOL(pci_release_regions);
928 EXPORT_SYMBOL(pci_request_regions);
929 EXPORT_SYMBOL(pci_release_region);
930 EXPORT_SYMBOL(pci_request_region);
931 EXPORT_SYMBOL(pci_set_master);
932 EXPORT_SYMBOL(pci_set_mwi);
933 EXPORT_SYMBOL(pci_clear_mwi);
934 EXPORT_SYMBOL_GPL(pci_intx);
935 EXPORT_SYMBOL(pci_set_dma_mask);
936 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
937 EXPORT_SYMBOL(pci_assign_resource);
938 EXPORT_SYMBOL(pci_find_parent_resource);
939
940 EXPORT_SYMBOL(pci_set_power_state);
941 EXPORT_SYMBOL(pci_save_state);
942 EXPORT_SYMBOL(pci_restore_state);
943 EXPORT_SYMBOL(pci_enable_wake);
944
945 /* Quirk info */
946
947 EXPORT_SYMBOL(isa_dma_bridge_buggy);
948 EXPORT_SYMBOL(pci_pci_problems);