PCI: pull pcibios_setup() up into core
[deliverable/linux.git] / drivers / pci / pci.c
1 /*
2 * PCI Bus Services, see include/linux/pci.h for further explanation.
3 *
4 * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
5 * David Mosberger-Tang
6 *
7 * Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
8 */
9
10 #include <linux/kernel.h>
11 #include <linux/delay.h>
12 #include <linux/init.h>
13 #include <linux/pci.h>
14 #include <linux/pm.h>
15 #include <linux/slab.h>
16 #include <linux/module.h>
17 #include <linux/spinlock.h>
18 #include <linux/string.h>
19 #include <linux/log2.h>
20 #include <linux/pci-aspm.h>
21 #include <linux/pm_wakeup.h>
22 #include <linux/interrupt.h>
23 #include <linux/device.h>
24 #include <linux/pm_runtime.h>
25 #include <asm-generic/pci-bridge.h>
26 #include <asm/setup.h>
27 #include "pci.h"
28
29 const char *pci_power_names[] = {
30 "error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
31 };
32 EXPORT_SYMBOL_GPL(pci_power_names);
33
34 int isa_dma_bridge_buggy;
35 EXPORT_SYMBOL(isa_dma_bridge_buggy);
36
37 int pci_pci_problems;
38 EXPORT_SYMBOL(pci_pci_problems);
39
40 unsigned int pci_pm_d3_delay;
41
42 static void pci_pme_list_scan(struct work_struct *work);
43
44 static LIST_HEAD(pci_pme_list);
45 static DEFINE_MUTEX(pci_pme_list_mutex);
46 static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan);
47
48 struct pci_pme_device {
49 struct list_head list;
50 struct pci_dev *dev;
51 };
52
53 #define PME_TIMEOUT 1000 /* How long between PME checks */
54
55 static void pci_dev_d3_sleep(struct pci_dev *dev)
56 {
57 unsigned int delay = dev->d3_delay;
58
59 if (delay < pci_pm_d3_delay)
60 delay = pci_pm_d3_delay;
61
62 msleep(delay);
63 }
64
65 #ifdef CONFIG_PCI_DOMAINS
66 int pci_domains_supported = 1;
67 #endif
68
69 #define DEFAULT_CARDBUS_IO_SIZE (256)
70 #define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
71 /* pci=cbmemsize=nnM,cbiosize=nn can override this */
72 unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
73 unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
74
75 #define DEFAULT_HOTPLUG_IO_SIZE (256)
76 #define DEFAULT_HOTPLUG_MEM_SIZE (2*1024*1024)
77 /* pci=hpmemsize=nnM,hpiosize=nn can override this */
78 unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE;
79 unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
80
81 enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_TUNE_OFF;
82
83 /*
84 * The default CLS is used if arch didn't set CLS explicitly and not
85 * all pci devices agree on the same value. Arch can override either
86 * the dfl or actual value as it sees fit. Don't forget this is
87 * measured in 32-bit words, not bytes.
88 */
89 u8 pci_dfl_cache_line_size __devinitdata = L1_CACHE_BYTES >> 2;
90 u8 pci_cache_line_size;
91
92 /*
93 * If we set up a device for bus mastering, we need to check the latency
94 * timer as certain BIOSes forget to set it properly.
95 */
96 unsigned int pcibios_max_latency = 255;
97
98 /* If set, the PCIe ARI capability will not be used. */
99 static bool pcie_ari_disabled;
100
101 /**
102 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
103 * @bus: pointer to PCI bus structure to search
104 *
105 * Given a PCI bus, returns the highest PCI bus number present in the set
106 * including the given PCI bus and its list of child PCI buses.
107 */
108 unsigned char pci_bus_max_busnr(struct pci_bus* bus)
109 {
110 struct list_head *tmp;
111 unsigned char max, n;
112
113 max = bus->subordinate;
114 list_for_each(tmp, &bus->children) {
115 n = pci_bus_max_busnr(pci_bus_b(tmp));
116 if(n > max)
117 max = n;
118 }
119 return max;
120 }
121 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
122
123 #ifdef CONFIG_HAS_IOMEM
124 void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
125 {
126 /*
127 * Make sure the BAR is actually a memory resource, not an IO resource
128 */
129 if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
130 WARN_ON(1);
131 return NULL;
132 }
133 return ioremap_nocache(pci_resource_start(pdev, bar),
134 pci_resource_len(pdev, bar));
135 }
136 EXPORT_SYMBOL_GPL(pci_ioremap_bar);
137 #endif
138
139 #if 0
140 /**
141 * pci_max_busnr - returns maximum PCI bus number
142 *
143 * Returns the highest PCI bus number present in the system global list of
144 * PCI buses.
145 */
146 unsigned char __devinit
147 pci_max_busnr(void)
148 {
149 struct pci_bus *bus = NULL;
150 unsigned char max, n;
151
152 max = 0;
153 while ((bus = pci_find_next_bus(bus)) != NULL) {
154 n = pci_bus_max_busnr(bus);
155 if(n > max)
156 max = n;
157 }
158 return max;
159 }
160
161 #endif /* 0 */
162
163 #define PCI_FIND_CAP_TTL 48
164
165 static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
166 u8 pos, int cap, int *ttl)
167 {
168 u8 id;
169
170 while ((*ttl)--) {
171 pci_bus_read_config_byte(bus, devfn, pos, &pos);
172 if (pos < 0x40)
173 break;
174 pos &= ~3;
175 pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
176 &id);
177 if (id == 0xff)
178 break;
179 if (id == cap)
180 return pos;
181 pos += PCI_CAP_LIST_NEXT;
182 }
183 return 0;
184 }
185
186 static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
187 u8 pos, int cap)
188 {
189 int ttl = PCI_FIND_CAP_TTL;
190
191 return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
192 }
193
194 int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
195 {
196 return __pci_find_next_cap(dev->bus, dev->devfn,
197 pos + PCI_CAP_LIST_NEXT, cap);
198 }
199 EXPORT_SYMBOL_GPL(pci_find_next_capability);
200
201 static int __pci_bus_find_cap_start(struct pci_bus *bus,
202 unsigned int devfn, u8 hdr_type)
203 {
204 u16 status;
205
206 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
207 if (!(status & PCI_STATUS_CAP_LIST))
208 return 0;
209
210 switch (hdr_type) {
211 case PCI_HEADER_TYPE_NORMAL:
212 case PCI_HEADER_TYPE_BRIDGE:
213 return PCI_CAPABILITY_LIST;
214 case PCI_HEADER_TYPE_CARDBUS:
215 return PCI_CB_CAPABILITY_LIST;
216 default:
217 return 0;
218 }
219
220 return 0;
221 }
222
223 /**
224 * pci_find_capability - query for devices' capabilities
225 * @dev: PCI device to query
226 * @cap: capability code
227 *
228 * Tell if a device supports a given PCI capability.
229 * Returns the address of the requested capability structure within the
230 * device's PCI configuration space or 0 in case the device does not
231 * support it. Possible values for @cap:
232 *
233 * %PCI_CAP_ID_PM Power Management
234 * %PCI_CAP_ID_AGP Accelerated Graphics Port
235 * %PCI_CAP_ID_VPD Vital Product Data
236 * %PCI_CAP_ID_SLOTID Slot Identification
237 * %PCI_CAP_ID_MSI Message Signalled Interrupts
238 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
239 * %PCI_CAP_ID_PCIX PCI-X
240 * %PCI_CAP_ID_EXP PCI Express
241 */
242 int pci_find_capability(struct pci_dev *dev, int cap)
243 {
244 int pos;
245
246 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
247 if (pos)
248 pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
249
250 return pos;
251 }
252
253 /**
254 * pci_bus_find_capability - query for devices' capabilities
255 * @bus: the PCI bus to query
256 * @devfn: PCI device to query
257 * @cap: capability code
258 *
259 * Like pci_find_capability() but works for pci devices that do not have a
260 * pci_dev structure set up yet.
261 *
262 * Returns the address of the requested capability structure within the
263 * device's PCI configuration space or 0 in case the device does not
264 * support it.
265 */
266 int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
267 {
268 int pos;
269 u8 hdr_type;
270
271 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
272
273 pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
274 if (pos)
275 pos = __pci_find_next_cap(bus, devfn, pos, cap);
276
277 return pos;
278 }
279
280 /**
281 * pci_find_ext_capability - Find an extended capability
282 * @dev: PCI device to query
283 * @cap: capability code
284 *
285 * Returns the address of the requested extended capability structure
286 * within the device's PCI configuration space or 0 if the device does
287 * not support it. Possible values for @cap:
288 *
289 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
290 * %PCI_EXT_CAP_ID_VC Virtual Channel
291 * %PCI_EXT_CAP_ID_DSN Device Serial Number
292 * %PCI_EXT_CAP_ID_PWR Power Budgeting
293 */
294 int pci_find_ext_capability(struct pci_dev *dev, int cap)
295 {
296 u32 header;
297 int ttl;
298 int pos = PCI_CFG_SPACE_SIZE;
299
300 /* minimum 8 bytes per capability */
301 ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
302
303 if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
304 return 0;
305
306 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
307 return 0;
308
309 /*
310 * If we have no capabilities, this is indicated by cap ID,
311 * cap version and next pointer all being 0.
312 */
313 if (header == 0)
314 return 0;
315
316 while (ttl-- > 0) {
317 if (PCI_EXT_CAP_ID(header) == cap)
318 return pos;
319
320 pos = PCI_EXT_CAP_NEXT(header);
321 if (pos < PCI_CFG_SPACE_SIZE)
322 break;
323
324 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
325 break;
326 }
327
328 return 0;
329 }
330 EXPORT_SYMBOL_GPL(pci_find_ext_capability);
331
332 /**
333 * pci_bus_find_ext_capability - find an extended capability
334 * @bus: the PCI bus to query
335 * @devfn: PCI device to query
336 * @cap: capability code
337 *
338 * Like pci_find_ext_capability() but works for pci devices that do not have a
339 * pci_dev structure set up yet.
340 *
341 * Returns the address of the requested capability structure within the
342 * device's PCI configuration space or 0 in case the device does not
343 * support it.
344 */
345 int pci_bus_find_ext_capability(struct pci_bus *bus, unsigned int devfn,
346 int cap)
347 {
348 u32 header;
349 int ttl;
350 int pos = PCI_CFG_SPACE_SIZE;
351
352 /* minimum 8 bytes per capability */
353 ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
354
355 if (!pci_bus_read_config_dword(bus, devfn, pos, &header))
356 return 0;
357 if (header == 0xffffffff || header == 0)
358 return 0;
359
360 while (ttl-- > 0) {
361 if (PCI_EXT_CAP_ID(header) == cap)
362 return pos;
363
364 pos = PCI_EXT_CAP_NEXT(header);
365 if (pos < PCI_CFG_SPACE_SIZE)
366 break;
367
368 if (!pci_bus_read_config_dword(bus, devfn, pos, &header))
369 break;
370 }
371
372 return 0;
373 }
374
375 static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
376 {
377 int rc, ttl = PCI_FIND_CAP_TTL;
378 u8 cap, mask;
379
380 if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
381 mask = HT_3BIT_CAP_MASK;
382 else
383 mask = HT_5BIT_CAP_MASK;
384
385 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
386 PCI_CAP_ID_HT, &ttl);
387 while (pos) {
388 rc = pci_read_config_byte(dev, pos + 3, &cap);
389 if (rc != PCIBIOS_SUCCESSFUL)
390 return 0;
391
392 if ((cap & mask) == ht_cap)
393 return pos;
394
395 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
396 pos + PCI_CAP_LIST_NEXT,
397 PCI_CAP_ID_HT, &ttl);
398 }
399
400 return 0;
401 }
402 /**
403 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
404 * @dev: PCI device to query
405 * @pos: Position from which to continue searching
406 * @ht_cap: Hypertransport capability code
407 *
408 * To be used in conjunction with pci_find_ht_capability() to search for
409 * all capabilities matching @ht_cap. @pos should always be a value returned
410 * from pci_find_ht_capability().
411 *
412 * NB. To be 100% safe against broken PCI devices, the caller should take
413 * steps to avoid an infinite loop.
414 */
415 int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
416 {
417 return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
418 }
419 EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
420
421 /**
422 * pci_find_ht_capability - query a device's Hypertransport capabilities
423 * @dev: PCI device to query
424 * @ht_cap: Hypertransport capability code
425 *
426 * Tell if a device supports a given Hypertransport capability.
427 * Returns an address within the device's PCI configuration space
428 * or 0 in case the device does not support the request capability.
429 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
430 * which has a Hypertransport capability matching @ht_cap.
431 */
432 int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
433 {
434 int pos;
435
436 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
437 if (pos)
438 pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
439
440 return pos;
441 }
442 EXPORT_SYMBOL_GPL(pci_find_ht_capability);
443
444 /**
445 * pci_find_parent_resource - return resource region of parent bus of given region
446 * @dev: PCI device structure contains resources to be searched
447 * @res: child resource record for which parent is sought
448 *
449 * For given resource region of given device, return the resource
450 * region of parent bus the given region is contained in or where
451 * it should be allocated from.
452 */
453 struct resource *
454 pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
455 {
456 const struct pci_bus *bus = dev->bus;
457 int i;
458 struct resource *best = NULL, *r;
459
460 pci_bus_for_each_resource(bus, r, i) {
461 if (!r)
462 continue;
463 if (res->start && !(res->start >= r->start && res->end <= r->end))
464 continue; /* Not contained */
465 if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
466 continue; /* Wrong type */
467 if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
468 return r; /* Exact match */
469 /* We can't insert a non-prefetch resource inside a prefetchable parent .. */
470 if (r->flags & IORESOURCE_PREFETCH)
471 continue;
472 /* .. but we can put a prefetchable resource inside a non-prefetchable one */
473 if (!best)
474 best = r;
475 }
476 return best;
477 }
478
479 /**
480 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
481 * @dev: PCI device to have its BARs restored
482 *
483 * Restore the BAR values for a given device, so as to make it
484 * accessible by its driver.
485 */
486 static void
487 pci_restore_bars(struct pci_dev *dev)
488 {
489 int i;
490
491 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
492 pci_update_resource(dev, i);
493 }
494
495 static struct pci_platform_pm_ops *pci_platform_pm;
496
497 int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
498 {
499 if (!ops->is_manageable || !ops->set_state || !ops->choose_state
500 || !ops->sleep_wake || !ops->can_wakeup)
501 return -EINVAL;
502 pci_platform_pm = ops;
503 return 0;
504 }
505
506 static inline bool platform_pci_power_manageable(struct pci_dev *dev)
507 {
508 return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
509 }
510
511 static inline int platform_pci_set_power_state(struct pci_dev *dev,
512 pci_power_t t)
513 {
514 return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
515 }
516
517 static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
518 {
519 return pci_platform_pm ?
520 pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
521 }
522
523 static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
524 {
525 return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
526 }
527
528 static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
529 {
530 return pci_platform_pm ?
531 pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
532 }
533
534 static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable)
535 {
536 return pci_platform_pm ?
537 pci_platform_pm->run_wake(dev, enable) : -ENODEV;
538 }
539
540 /**
541 * pci_raw_set_power_state - Use PCI PM registers to set the power state of
542 * given PCI device
543 * @dev: PCI device to handle.
544 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
545 *
546 * RETURN VALUE:
547 * -EINVAL if the requested state is invalid.
548 * -EIO if device does not support PCI PM or its PM capabilities register has a
549 * wrong version, or device doesn't support the requested state.
550 * 0 if device already is in the requested state.
551 * 0 if device's power state has been successfully changed.
552 */
553 static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
554 {
555 u16 pmcsr;
556 bool need_restore = false;
557
558 /* Check if we're already there */
559 if (dev->current_state == state)
560 return 0;
561
562 if (!dev->pm_cap)
563 return -EIO;
564
565 if (state < PCI_D0 || state > PCI_D3hot)
566 return -EINVAL;
567
568 /* Validate current state:
569 * Can enter D0 from any state, but if we can only go deeper
570 * to sleep if we're already in a low power state
571 */
572 if (state != PCI_D0 && dev->current_state <= PCI_D3cold
573 && dev->current_state > state) {
574 dev_err(&dev->dev, "invalid power transition "
575 "(from state %d to %d)\n", dev->current_state, state);
576 return -EINVAL;
577 }
578
579 /* check if this device supports the desired state */
580 if ((state == PCI_D1 && !dev->d1_support)
581 || (state == PCI_D2 && !dev->d2_support))
582 return -EIO;
583
584 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
585
586 /* If we're (effectively) in D3, force entire word to 0.
587 * This doesn't affect PME_Status, disables PME_En, and
588 * sets PowerState to 0.
589 */
590 switch (dev->current_state) {
591 case PCI_D0:
592 case PCI_D1:
593 case PCI_D2:
594 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
595 pmcsr |= state;
596 break;
597 case PCI_D3hot:
598 case PCI_D3cold:
599 case PCI_UNKNOWN: /* Boot-up */
600 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
601 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
602 need_restore = true;
603 /* Fall-through: force to D0 */
604 default:
605 pmcsr = 0;
606 break;
607 }
608
609 /* enter specified state */
610 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
611
612 /* Mandatory power management transition delays */
613 /* see PCI PM 1.1 5.6.1 table 18 */
614 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
615 pci_dev_d3_sleep(dev);
616 else if (state == PCI_D2 || dev->current_state == PCI_D2)
617 udelay(PCI_PM_D2_DELAY);
618
619 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
620 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
621 if (dev->current_state != state && printk_ratelimit())
622 dev_info(&dev->dev, "Refused to change power state, "
623 "currently in D%d\n", dev->current_state);
624
625 /* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
626 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
627 * from D3hot to D0 _may_ perform an internal reset, thereby
628 * going to "D0 Uninitialized" rather than "D0 Initialized".
629 * For example, at least some versions of the 3c905B and the
630 * 3c556B exhibit this behaviour.
631 *
632 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
633 * devices in a D3hot state at boot. Consequently, we need to
634 * restore at least the BARs so that the device will be
635 * accessible to its driver.
636 */
637 if (need_restore)
638 pci_restore_bars(dev);
639
640 if (dev->bus->self)
641 pcie_aspm_pm_state_change(dev->bus->self);
642
643 return 0;
644 }
645
646 /**
647 * pci_update_current_state - Read PCI power state of given device from its
648 * PCI PM registers and cache it
649 * @dev: PCI device to handle.
650 * @state: State to cache in case the device doesn't have the PM capability
651 */
652 void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
653 {
654 if (dev->pm_cap) {
655 u16 pmcsr;
656
657 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
658 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
659 } else {
660 dev->current_state = state;
661 }
662 }
663
664 /**
665 * pci_platform_power_transition - Use platform to change device power state
666 * @dev: PCI device to handle.
667 * @state: State to put the device into.
668 */
669 static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
670 {
671 int error;
672
673 if (platform_pci_power_manageable(dev)) {
674 error = platform_pci_set_power_state(dev, state);
675 if (!error)
676 pci_update_current_state(dev, state);
677 /* Fall back to PCI_D0 if native PM is not supported */
678 if (!dev->pm_cap)
679 dev->current_state = PCI_D0;
680 } else {
681 error = -ENODEV;
682 /* Fall back to PCI_D0 if native PM is not supported */
683 if (!dev->pm_cap)
684 dev->current_state = PCI_D0;
685 }
686
687 return error;
688 }
689
690 /**
691 * __pci_start_power_transition - Start power transition of a PCI device
692 * @dev: PCI device to handle.
693 * @state: State to put the device into.
694 */
695 static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
696 {
697 if (state == PCI_D0)
698 pci_platform_power_transition(dev, PCI_D0);
699 }
700
701 /**
702 * __pci_complete_power_transition - Complete power transition of a PCI device
703 * @dev: PCI device to handle.
704 * @state: State to put the device into.
705 *
706 * This function should not be called directly by device drivers.
707 */
708 int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
709 {
710 return state >= PCI_D0 ?
711 pci_platform_power_transition(dev, state) : -EINVAL;
712 }
713 EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
714
715 /**
716 * pci_set_power_state - Set the power state of a PCI device
717 * @dev: PCI device to handle.
718 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
719 *
720 * Transition a device to a new power state, using the platform firmware and/or
721 * the device's PCI PM registers.
722 *
723 * RETURN VALUE:
724 * -EINVAL if the requested state is invalid.
725 * -EIO if device does not support PCI PM or its PM capabilities register has a
726 * wrong version, or device doesn't support the requested state.
727 * 0 if device already is in the requested state.
728 * 0 if device's power state has been successfully changed.
729 */
730 int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
731 {
732 int error;
733
734 /* bound the state we're entering */
735 if (state > PCI_D3hot)
736 state = PCI_D3hot;
737 else if (state < PCI_D0)
738 state = PCI_D0;
739 else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
740 /*
741 * If the device or the parent bridge do not support PCI PM,
742 * ignore the request if we're doing anything other than putting
743 * it into D0 (which would only happen on boot).
744 */
745 return 0;
746
747 __pci_start_power_transition(dev, state);
748
749 /* This device is quirked not to be put into D3, so
750 don't put it in D3 */
751 if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
752 return 0;
753
754 error = pci_raw_set_power_state(dev, state);
755
756 if (!__pci_complete_power_transition(dev, state))
757 error = 0;
758 /*
759 * When aspm_policy is "powersave" this call ensures
760 * that ASPM is configured.
761 */
762 if (!error && dev->bus->self)
763 pcie_aspm_powersave_config_link(dev->bus->self);
764
765 return error;
766 }
767
768 /**
769 * pci_choose_state - Choose the power state of a PCI device
770 * @dev: PCI device to be suspended
771 * @state: target sleep state for the whole system. This is the value
772 * that is passed to suspend() function.
773 *
774 * Returns PCI power state suitable for given device and given system
775 * message.
776 */
777
778 pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
779 {
780 pci_power_t ret;
781
782 if (!pci_find_capability(dev, PCI_CAP_ID_PM))
783 return PCI_D0;
784
785 ret = platform_pci_choose_state(dev);
786 if (ret != PCI_POWER_ERROR)
787 return ret;
788
789 switch (state.event) {
790 case PM_EVENT_ON:
791 return PCI_D0;
792 case PM_EVENT_FREEZE:
793 case PM_EVENT_PRETHAW:
794 /* REVISIT both freeze and pre-thaw "should" use D0 */
795 case PM_EVENT_SUSPEND:
796 case PM_EVENT_HIBERNATE:
797 return PCI_D3hot;
798 default:
799 dev_info(&dev->dev, "unrecognized suspend event %d\n",
800 state.event);
801 BUG();
802 }
803 return PCI_D0;
804 }
805
806 EXPORT_SYMBOL(pci_choose_state);
807
808 #define PCI_EXP_SAVE_REGS 7
809
810 #define pcie_cap_has_devctl(type, flags) 1
811 #define pcie_cap_has_lnkctl(type, flags) \
812 ((flags & PCI_EXP_FLAGS_VERS) > 1 || \
813 (type == PCI_EXP_TYPE_ROOT_PORT || \
814 type == PCI_EXP_TYPE_ENDPOINT || \
815 type == PCI_EXP_TYPE_LEG_END))
816 #define pcie_cap_has_sltctl(type, flags) \
817 ((flags & PCI_EXP_FLAGS_VERS) > 1 || \
818 ((type == PCI_EXP_TYPE_ROOT_PORT) || \
819 (type == PCI_EXP_TYPE_DOWNSTREAM && \
820 (flags & PCI_EXP_FLAGS_SLOT))))
821 #define pcie_cap_has_rtctl(type, flags) \
822 ((flags & PCI_EXP_FLAGS_VERS) > 1 || \
823 (type == PCI_EXP_TYPE_ROOT_PORT || \
824 type == PCI_EXP_TYPE_RC_EC))
825 #define pcie_cap_has_devctl2(type, flags) \
826 ((flags & PCI_EXP_FLAGS_VERS) > 1)
827 #define pcie_cap_has_lnkctl2(type, flags) \
828 ((flags & PCI_EXP_FLAGS_VERS) > 1)
829 #define pcie_cap_has_sltctl2(type, flags) \
830 ((flags & PCI_EXP_FLAGS_VERS) > 1)
831
832 static struct pci_cap_saved_state *pci_find_saved_cap(
833 struct pci_dev *pci_dev, char cap)
834 {
835 struct pci_cap_saved_state *tmp;
836 struct hlist_node *pos;
837
838 hlist_for_each_entry(tmp, pos, &pci_dev->saved_cap_space, next) {
839 if (tmp->cap.cap_nr == cap)
840 return tmp;
841 }
842 return NULL;
843 }
844
845 static int pci_save_pcie_state(struct pci_dev *dev)
846 {
847 int pos, i = 0;
848 struct pci_cap_saved_state *save_state;
849 u16 *cap;
850 u16 flags;
851
852 pos = pci_pcie_cap(dev);
853 if (!pos)
854 return 0;
855
856 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
857 if (!save_state) {
858 dev_err(&dev->dev, "buffer not found in %s\n", __func__);
859 return -ENOMEM;
860 }
861 cap = (u16 *)&save_state->cap.data[0];
862
863 pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
864
865 if (pcie_cap_has_devctl(dev->pcie_type, flags))
866 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
867 if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
868 pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
869 if (pcie_cap_has_sltctl(dev->pcie_type, flags))
870 pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
871 if (pcie_cap_has_rtctl(dev->pcie_type, flags))
872 pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
873 if (pcie_cap_has_devctl2(dev->pcie_type, flags))
874 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &cap[i++]);
875 if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
876 pci_read_config_word(dev, pos + PCI_EXP_LNKCTL2, &cap[i++]);
877 if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
878 pci_read_config_word(dev, pos + PCI_EXP_SLTCTL2, &cap[i++]);
879
880 return 0;
881 }
882
883 static void pci_restore_pcie_state(struct pci_dev *dev)
884 {
885 int i = 0, pos;
886 struct pci_cap_saved_state *save_state;
887 u16 *cap;
888 u16 flags;
889
890 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
891 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
892 if (!save_state || pos <= 0)
893 return;
894 cap = (u16 *)&save_state->cap.data[0];
895
896 pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
897
898 if (pcie_cap_has_devctl(dev->pcie_type, flags))
899 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
900 if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
901 pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
902 if (pcie_cap_has_sltctl(dev->pcie_type, flags))
903 pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
904 if (pcie_cap_has_rtctl(dev->pcie_type, flags))
905 pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
906 if (pcie_cap_has_devctl2(dev->pcie_type, flags))
907 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, cap[i++]);
908 if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
909 pci_write_config_word(dev, pos + PCI_EXP_LNKCTL2, cap[i++]);
910 if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
911 pci_write_config_word(dev, pos + PCI_EXP_SLTCTL2, cap[i++]);
912 }
913
914
915 static int pci_save_pcix_state(struct pci_dev *dev)
916 {
917 int pos;
918 struct pci_cap_saved_state *save_state;
919
920 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
921 if (pos <= 0)
922 return 0;
923
924 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
925 if (!save_state) {
926 dev_err(&dev->dev, "buffer not found in %s\n", __func__);
927 return -ENOMEM;
928 }
929
930 pci_read_config_word(dev, pos + PCI_X_CMD,
931 (u16 *)save_state->cap.data);
932
933 return 0;
934 }
935
936 static void pci_restore_pcix_state(struct pci_dev *dev)
937 {
938 int i = 0, pos;
939 struct pci_cap_saved_state *save_state;
940 u16 *cap;
941
942 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
943 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
944 if (!save_state || pos <= 0)
945 return;
946 cap = (u16 *)&save_state->cap.data[0];
947
948 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
949 }
950
951
952 /**
953 * pci_save_state - save the PCI configuration space of a device before suspending
954 * @dev: - PCI device that we're dealing with
955 */
956 int
957 pci_save_state(struct pci_dev *dev)
958 {
959 int i;
960 /* XXX: 100% dword access ok here? */
961 for (i = 0; i < 16; i++)
962 pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
963 dev->state_saved = true;
964 if ((i = pci_save_pcie_state(dev)) != 0)
965 return i;
966 if ((i = pci_save_pcix_state(dev)) != 0)
967 return i;
968 return 0;
969 }
970
971 static void pci_restore_config_dword(struct pci_dev *pdev, int offset,
972 u32 saved_val, int retry)
973 {
974 u32 val;
975
976 pci_read_config_dword(pdev, offset, &val);
977 if (val == saved_val)
978 return;
979
980 for (;;) {
981 dev_dbg(&pdev->dev, "restoring config space at offset "
982 "%#x (was %#x, writing %#x)\n", offset, val, saved_val);
983 pci_write_config_dword(pdev, offset, saved_val);
984 if (retry-- <= 0)
985 return;
986
987 pci_read_config_dword(pdev, offset, &val);
988 if (val == saved_val)
989 return;
990
991 mdelay(1);
992 }
993 }
994
995 static void pci_restore_config_space_range(struct pci_dev *pdev,
996 int start, int end, int retry)
997 {
998 int index;
999
1000 for (index = end; index >= start; index--)
1001 pci_restore_config_dword(pdev, 4 * index,
1002 pdev->saved_config_space[index],
1003 retry);
1004 }
1005
1006 static void pci_restore_config_space(struct pci_dev *pdev)
1007 {
1008 if (pdev->hdr_type == PCI_HEADER_TYPE_NORMAL) {
1009 pci_restore_config_space_range(pdev, 10, 15, 0);
1010 /* Restore BARs before the command register. */
1011 pci_restore_config_space_range(pdev, 4, 9, 10);
1012 pci_restore_config_space_range(pdev, 0, 3, 0);
1013 } else {
1014 pci_restore_config_space_range(pdev, 0, 15, 0);
1015 }
1016 }
1017
1018 /**
1019 * pci_restore_state - Restore the saved state of a PCI device
1020 * @dev: - PCI device that we're dealing with
1021 */
1022 void pci_restore_state(struct pci_dev *dev)
1023 {
1024 if (!dev->state_saved)
1025 return;
1026
1027 /* PCI Express register must be restored first */
1028 pci_restore_pcie_state(dev);
1029 pci_restore_ats_state(dev);
1030
1031 pci_restore_config_space(dev);
1032
1033 pci_restore_pcix_state(dev);
1034 pci_restore_msi_state(dev);
1035 pci_restore_iov_state(dev);
1036
1037 dev->state_saved = false;
1038 }
1039
1040 struct pci_saved_state {
1041 u32 config_space[16];
1042 struct pci_cap_saved_data cap[0];
1043 };
1044
1045 /**
1046 * pci_store_saved_state - Allocate and return an opaque struct containing
1047 * the device saved state.
1048 * @dev: PCI device that we're dealing with
1049 *
1050 * Rerturn NULL if no state or error.
1051 */
1052 struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev)
1053 {
1054 struct pci_saved_state *state;
1055 struct pci_cap_saved_state *tmp;
1056 struct pci_cap_saved_data *cap;
1057 struct hlist_node *pos;
1058 size_t size;
1059
1060 if (!dev->state_saved)
1061 return NULL;
1062
1063 size = sizeof(*state) + sizeof(struct pci_cap_saved_data);
1064
1065 hlist_for_each_entry(tmp, pos, &dev->saved_cap_space, next)
1066 size += sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1067
1068 state = kzalloc(size, GFP_KERNEL);
1069 if (!state)
1070 return NULL;
1071
1072 memcpy(state->config_space, dev->saved_config_space,
1073 sizeof(state->config_space));
1074
1075 cap = state->cap;
1076 hlist_for_each_entry(tmp, pos, &dev->saved_cap_space, next) {
1077 size_t len = sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1078 memcpy(cap, &tmp->cap, len);
1079 cap = (struct pci_cap_saved_data *)((u8 *)cap + len);
1080 }
1081 /* Empty cap_save terminates list */
1082
1083 return state;
1084 }
1085 EXPORT_SYMBOL_GPL(pci_store_saved_state);
1086
1087 /**
1088 * pci_load_saved_state - Reload the provided save state into struct pci_dev.
1089 * @dev: PCI device that we're dealing with
1090 * @state: Saved state returned from pci_store_saved_state()
1091 */
1092 int pci_load_saved_state(struct pci_dev *dev, struct pci_saved_state *state)
1093 {
1094 struct pci_cap_saved_data *cap;
1095
1096 dev->state_saved = false;
1097
1098 if (!state)
1099 return 0;
1100
1101 memcpy(dev->saved_config_space, state->config_space,
1102 sizeof(state->config_space));
1103
1104 cap = state->cap;
1105 while (cap->size) {
1106 struct pci_cap_saved_state *tmp;
1107
1108 tmp = pci_find_saved_cap(dev, cap->cap_nr);
1109 if (!tmp || tmp->cap.size != cap->size)
1110 return -EINVAL;
1111
1112 memcpy(tmp->cap.data, cap->data, tmp->cap.size);
1113 cap = (struct pci_cap_saved_data *)((u8 *)cap +
1114 sizeof(struct pci_cap_saved_data) + cap->size);
1115 }
1116
1117 dev->state_saved = true;
1118 return 0;
1119 }
1120 EXPORT_SYMBOL_GPL(pci_load_saved_state);
1121
1122 /**
1123 * pci_load_and_free_saved_state - Reload the save state pointed to by state,
1124 * and free the memory allocated for it.
1125 * @dev: PCI device that we're dealing with
1126 * @state: Pointer to saved state returned from pci_store_saved_state()
1127 */
1128 int pci_load_and_free_saved_state(struct pci_dev *dev,
1129 struct pci_saved_state **state)
1130 {
1131 int ret = pci_load_saved_state(dev, *state);
1132 kfree(*state);
1133 *state = NULL;
1134 return ret;
1135 }
1136 EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state);
1137
1138 static int do_pci_enable_device(struct pci_dev *dev, int bars)
1139 {
1140 int err;
1141
1142 err = pci_set_power_state(dev, PCI_D0);
1143 if (err < 0 && err != -EIO)
1144 return err;
1145 err = pcibios_enable_device(dev, bars);
1146 if (err < 0)
1147 return err;
1148 pci_fixup_device(pci_fixup_enable, dev);
1149
1150 return 0;
1151 }
1152
1153 /**
1154 * pci_reenable_device - Resume abandoned device
1155 * @dev: PCI device to be resumed
1156 *
1157 * Note this function is a backend of pci_default_resume and is not supposed
1158 * to be called by normal code, write proper resume handler and use it instead.
1159 */
1160 int pci_reenable_device(struct pci_dev *dev)
1161 {
1162 if (pci_is_enabled(dev))
1163 return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
1164 return 0;
1165 }
1166
1167 static int __pci_enable_device_flags(struct pci_dev *dev,
1168 resource_size_t flags)
1169 {
1170 int err;
1171 int i, bars = 0;
1172
1173 /*
1174 * Power state could be unknown at this point, either due to a fresh
1175 * boot or a device removal call. So get the current power state
1176 * so that things like MSI message writing will behave as expected
1177 * (e.g. if the device really is in D0 at enable time).
1178 */
1179 if (dev->pm_cap) {
1180 u16 pmcsr;
1181 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1182 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
1183 }
1184
1185 if (atomic_add_return(1, &dev->enable_cnt) > 1)
1186 return 0; /* already enabled */
1187
1188 /* only skip sriov related */
1189 for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1190 if (dev->resource[i].flags & flags)
1191 bars |= (1 << i);
1192 for (i = PCI_BRIDGE_RESOURCES; i < DEVICE_COUNT_RESOURCE; i++)
1193 if (dev->resource[i].flags & flags)
1194 bars |= (1 << i);
1195
1196 err = do_pci_enable_device(dev, bars);
1197 if (err < 0)
1198 atomic_dec(&dev->enable_cnt);
1199 return err;
1200 }
1201
1202 /**
1203 * pci_enable_device_io - Initialize a device for use with IO space
1204 * @dev: PCI device to be initialized
1205 *
1206 * Initialize device before it's used by a driver. Ask low-level code
1207 * to enable I/O resources. Wake up the device if it was suspended.
1208 * Beware, this function can fail.
1209 */
1210 int pci_enable_device_io(struct pci_dev *dev)
1211 {
1212 return __pci_enable_device_flags(dev, IORESOURCE_IO);
1213 }
1214
1215 /**
1216 * pci_enable_device_mem - Initialize a device for use with Memory space
1217 * @dev: PCI device to be initialized
1218 *
1219 * Initialize device before it's used by a driver. Ask low-level code
1220 * to enable Memory resources. Wake up the device if it was suspended.
1221 * Beware, this function can fail.
1222 */
1223 int pci_enable_device_mem(struct pci_dev *dev)
1224 {
1225 return __pci_enable_device_flags(dev, IORESOURCE_MEM);
1226 }
1227
1228 /**
1229 * pci_enable_device - Initialize device before it's used by a driver.
1230 * @dev: PCI device to be initialized
1231 *
1232 * Initialize device before it's used by a driver. Ask low-level code
1233 * to enable I/O and memory. Wake up the device if it was suspended.
1234 * Beware, this function can fail.
1235 *
1236 * Note we don't actually enable the device many times if we call
1237 * this function repeatedly (we just increment the count).
1238 */
1239 int pci_enable_device(struct pci_dev *dev)
1240 {
1241 return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
1242 }
1243
1244 /*
1245 * Managed PCI resources. This manages device on/off, intx/msi/msix
1246 * on/off and BAR regions. pci_dev itself records msi/msix status, so
1247 * there's no need to track it separately. pci_devres is initialized
1248 * when a device is enabled using managed PCI device enable interface.
1249 */
1250 struct pci_devres {
1251 unsigned int enabled:1;
1252 unsigned int pinned:1;
1253 unsigned int orig_intx:1;
1254 unsigned int restore_intx:1;
1255 u32 region_mask;
1256 };
1257
1258 static void pcim_release(struct device *gendev, void *res)
1259 {
1260 struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
1261 struct pci_devres *this = res;
1262 int i;
1263
1264 if (dev->msi_enabled)
1265 pci_disable_msi(dev);
1266 if (dev->msix_enabled)
1267 pci_disable_msix(dev);
1268
1269 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1270 if (this->region_mask & (1 << i))
1271 pci_release_region(dev, i);
1272
1273 if (this->restore_intx)
1274 pci_intx(dev, this->orig_intx);
1275
1276 if (this->enabled && !this->pinned)
1277 pci_disable_device(dev);
1278 }
1279
1280 static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
1281 {
1282 struct pci_devres *dr, *new_dr;
1283
1284 dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1285 if (dr)
1286 return dr;
1287
1288 new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1289 if (!new_dr)
1290 return NULL;
1291 return devres_get(&pdev->dev, new_dr, NULL, NULL);
1292 }
1293
1294 static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
1295 {
1296 if (pci_is_managed(pdev))
1297 return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1298 return NULL;
1299 }
1300
1301 /**
1302 * pcim_enable_device - Managed pci_enable_device()
1303 * @pdev: PCI device to be initialized
1304 *
1305 * Managed pci_enable_device().
1306 */
1307 int pcim_enable_device(struct pci_dev *pdev)
1308 {
1309 struct pci_devres *dr;
1310 int rc;
1311
1312 dr = get_pci_dr(pdev);
1313 if (unlikely(!dr))
1314 return -ENOMEM;
1315 if (dr->enabled)
1316 return 0;
1317
1318 rc = pci_enable_device(pdev);
1319 if (!rc) {
1320 pdev->is_managed = 1;
1321 dr->enabled = 1;
1322 }
1323 return rc;
1324 }
1325
1326 /**
1327 * pcim_pin_device - Pin managed PCI device
1328 * @pdev: PCI device to pin
1329 *
1330 * Pin managed PCI device @pdev. Pinned device won't be disabled on
1331 * driver detach. @pdev must have been enabled with
1332 * pcim_enable_device().
1333 */
1334 void pcim_pin_device(struct pci_dev *pdev)
1335 {
1336 struct pci_devres *dr;
1337
1338 dr = find_pci_dr(pdev);
1339 WARN_ON(!dr || !dr->enabled);
1340 if (dr)
1341 dr->pinned = 1;
1342 }
1343
1344 /**
1345 * pcibios_disable_device - disable arch specific PCI resources for device dev
1346 * @dev: the PCI device to disable
1347 *
1348 * Disables architecture specific PCI resources for the device. This
1349 * is the default implementation. Architecture implementations can
1350 * override this.
1351 */
1352 void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
1353
1354 static void do_pci_disable_device(struct pci_dev *dev)
1355 {
1356 u16 pci_command;
1357
1358 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1359 if (pci_command & PCI_COMMAND_MASTER) {
1360 pci_command &= ~PCI_COMMAND_MASTER;
1361 pci_write_config_word(dev, PCI_COMMAND, pci_command);
1362 }
1363
1364 pcibios_disable_device(dev);
1365 }
1366
1367 /**
1368 * pci_disable_enabled_device - Disable device without updating enable_cnt
1369 * @dev: PCI device to disable
1370 *
1371 * NOTE: This function is a backend of PCI power management routines and is
1372 * not supposed to be called drivers.
1373 */
1374 void pci_disable_enabled_device(struct pci_dev *dev)
1375 {
1376 if (pci_is_enabled(dev))
1377 do_pci_disable_device(dev);
1378 }
1379
1380 /**
1381 * pci_disable_device - Disable PCI device after use
1382 * @dev: PCI device to be disabled
1383 *
1384 * Signal to the system that the PCI device is not in use by the system
1385 * anymore. This only involves disabling PCI bus-mastering, if active.
1386 *
1387 * Note we don't actually disable the device until all callers of
1388 * pci_enable_device() have called pci_disable_device().
1389 */
1390 void
1391 pci_disable_device(struct pci_dev *dev)
1392 {
1393 struct pci_devres *dr;
1394
1395 dr = find_pci_dr(dev);
1396 if (dr)
1397 dr->enabled = 0;
1398
1399 if (atomic_sub_return(1, &dev->enable_cnt) != 0)
1400 return;
1401
1402 do_pci_disable_device(dev);
1403
1404 dev->is_busmaster = 0;
1405 }
1406
1407 /**
1408 * pcibios_set_pcie_reset_state - set reset state for device dev
1409 * @dev: the PCIe device reset
1410 * @state: Reset state to enter into
1411 *
1412 *
1413 * Sets the PCIe reset state for the device. This is the default
1414 * implementation. Architecture implementations can override this.
1415 */
1416 int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
1417 enum pcie_reset_state state)
1418 {
1419 return -EINVAL;
1420 }
1421
1422 /**
1423 * pci_set_pcie_reset_state - set reset state for device dev
1424 * @dev: the PCIe device reset
1425 * @state: Reset state to enter into
1426 *
1427 *
1428 * Sets the PCI reset state for the device.
1429 */
1430 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1431 {
1432 return pcibios_set_pcie_reset_state(dev, state);
1433 }
1434
1435 /**
1436 * pci_check_pme_status - Check if given device has generated PME.
1437 * @dev: Device to check.
1438 *
1439 * Check the PME status of the device and if set, clear it and clear PME enable
1440 * (if set). Return 'true' if PME status and PME enable were both set or
1441 * 'false' otherwise.
1442 */
1443 bool pci_check_pme_status(struct pci_dev *dev)
1444 {
1445 int pmcsr_pos;
1446 u16 pmcsr;
1447 bool ret = false;
1448
1449 if (!dev->pm_cap)
1450 return false;
1451
1452 pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
1453 pci_read_config_word(dev, pmcsr_pos, &pmcsr);
1454 if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
1455 return false;
1456
1457 /* Clear PME status. */
1458 pmcsr |= PCI_PM_CTRL_PME_STATUS;
1459 if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
1460 /* Disable PME to avoid interrupt flood. */
1461 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1462 ret = true;
1463 }
1464
1465 pci_write_config_word(dev, pmcsr_pos, pmcsr);
1466
1467 return ret;
1468 }
1469
1470 /**
1471 * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
1472 * @dev: Device to handle.
1473 * @pme_poll_reset: Whether or not to reset the device's pme_poll flag.
1474 *
1475 * Check if @dev has generated PME and queue a resume request for it in that
1476 * case.
1477 */
1478 static int pci_pme_wakeup(struct pci_dev *dev, void *pme_poll_reset)
1479 {
1480 if (pme_poll_reset && dev->pme_poll)
1481 dev->pme_poll = false;
1482
1483 if (pci_check_pme_status(dev)) {
1484 pci_wakeup_event(dev);
1485 pm_request_resume(&dev->dev);
1486 }
1487 return 0;
1488 }
1489
1490 /**
1491 * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
1492 * @bus: Top bus of the subtree to walk.
1493 */
1494 void pci_pme_wakeup_bus(struct pci_bus *bus)
1495 {
1496 if (bus)
1497 pci_walk_bus(bus, pci_pme_wakeup, (void *)true);
1498 }
1499
1500 /**
1501 * pci_pme_capable - check the capability of PCI device to generate PME#
1502 * @dev: PCI device to handle.
1503 * @state: PCI state from which device will issue PME#.
1504 */
1505 bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1506 {
1507 if (!dev->pm_cap)
1508 return false;
1509
1510 return !!(dev->pme_support & (1 << state));
1511 }
1512
1513 static void pci_pme_list_scan(struct work_struct *work)
1514 {
1515 struct pci_pme_device *pme_dev, *n;
1516
1517 mutex_lock(&pci_pme_list_mutex);
1518 if (!list_empty(&pci_pme_list)) {
1519 list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) {
1520 if (pme_dev->dev->pme_poll) {
1521 pci_pme_wakeup(pme_dev->dev, NULL);
1522 } else {
1523 list_del(&pme_dev->list);
1524 kfree(pme_dev);
1525 }
1526 }
1527 if (!list_empty(&pci_pme_list))
1528 schedule_delayed_work(&pci_pme_work,
1529 msecs_to_jiffies(PME_TIMEOUT));
1530 }
1531 mutex_unlock(&pci_pme_list_mutex);
1532 }
1533
1534 /**
1535 * pci_pme_active - enable or disable PCI device's PME# function
1536 * @dev: PCI device to handle.
1537 * @enable: 'true' to enable PME# generation; 'false' to disable it.
1538 *
1539 * The caller must verify that the device is capable of generating PME# before
1540 * calling this function with @enable equal to 'true'.
1541 */
1542 void pci_pme_active(struct pci_dev *dev, bool enable)
1543 {
1544 u16 pmcsr;
1545
1546 if (!dev->pm_cap)
1547 return;
1548
1549 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1550 /* Clear PME_Status by writing 1 to it and enable PME# */
1551 pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1552 if (!enable)
1553 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1554
1555 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1556
1557 /* PCI (as opposed to PCIe) PME requires that the device have
1558 its PME# line hooked up correctly. Not all hardware vendors
1559 do this, so the PME never gets delivered and the device
1560 remains asleep. The easiest way around this is to
1561 periodically walk the list of suspended devices and check
1562 whether any have their PME flag set. The assumption is that
1563 we'll wake up often enough anyway that this won't be a huge
1564 hit, and the power savings from the devices will still be a
1565 win. */
1566
1567 if (dev->pme_poll) {
1568 struct pci_pme_device *pme_dev;
1569 if (enable) {
1570 pme_dev = kmalloc(sizeof(struct pci_pme_device),
1571 GFP_KERNEL);
1572 if (!pme_dev)
1573 goto out;
1574 pme_dev->dev = dev;
1575 mutex_lock(&pci_pme_list_mutex);
1576 list_add(&pme_dev->list, &pci_pme_list);
1577 if (list_is_singular(&pci_pme_list))
1578 schedule_delayed_work(&pci_pme_work,
1579 msecs_to_jiffies(PME_TIMEOUT));
1580 mutex_unlock(&pci_pme_list_mutex);
1581 } else {
1582 mutex_lock(&pci_pme_list_mutex);
1583 list_for_each_entry(pme_dev, &pci_pme_list, list) {
1584 if (pme_dev->dev == dev) {
1585 list_del(&pme_dev->list);
1586 kfree(pme_dev);
1587 break;
1588 }
1589 }
1590 mutex_unlock(&pci_pme_list_mutex);
1591 }
1592 }
1593
1594 out:
1595 dev_dbg(&dev->dev, "PME# %s\n", enable ? "enabled" : "disabled");
1596 }
1597
1598 /**
1599 * __pci_enable_wake - enable PCI device as wakeup event source
1600 * @dev: PCI device affected
1601 * @state: PCI state from which device will issue wakeup events
1602 * @runtime: True if the events are to be generated at run time
1603 * @enable: True to enable event generation; false to disable
1604 *
1605 * This enables the device as a wakeup event source, or disables it.
1606 * When such events involves platform-specific hooks, those hooks are
1607 * called automatically by this routine.
1608 *
1609 * Devices with legacy power management (no standard PCI PM capabilities)
1610 * always require such platform hooks.
1611 *
1612 * RETURN VALUE:
1613 * 0 is returned on success
1614 * -EINVAL is returned if device is not supposed to wake up the system
1615 * Error code depending on the platform is returned if both the platform and
1616 * the native mechanism fail to enable the generation of wake-up events
1617 */
1618 int __pci_enable_wake(struct pci_dev *dev, pci_power_t state,
1619 bool runtime, bool enable)
1620 {
1621 int ret = 0;
1622
1623 if (enable && !runtime && !device_may_wakeup(&dev->dev))
1624 return -EINVAL;
1625
1626 /* Don't do the same thing twice in a row for one device. */
1627 if (!!enable == !!dev->wakeup_prepared)
1628 return 0;
1629
1630 /*
1631 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1632 * Anderson we should be doing PME# wake enable followed by ACPI wake
1633 * enable. To disable wake-up we call the platform first, for symmetry.
1634 */
1635
1636 if (enable) {
1637 int error;
1638
1639 if (pci_pme_capable(dev, state))
1640 pci_pme_active(dev, true);
1641 else
1642 ret = 1;
1643 error = runtime ? platform_pci_run_wake(dev, true) :
1644 platform_pci_sleep_wake(dev, true);
1645 if (ret)
1646 ret = error;
1647 if (!ret)
1648 dev->wakeup_prepared = true;
1649 } else {
1650 if (runtime)
1651 platform_pci_run_wake(dev, false);
1652 else
1653 platform_pci_sleep_wake(dev, false);
1654 pci_pme_active(dev, false);
1655 dev->wakeup_prepared = false;
1656 }
1657
1658 return ret;
1659 }
1660 EXPORT_SYMBOL(__pci_enable_wake);
1661
1662 /**
1663 * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1664 * @dev: PCI device to prepare
1665 * @enable: True to enable wake-up event generation; false to disable
1666 *
1667 * Many drivers want the device to wake up the system from D3_hot or D3_cold
1668 * and this function allows them to set that up cleanly - pci_enable_wake()
1669 * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1670 * ordering constraints.
1671 *
1672 * This function only returns error code if the device is not capable of
1673 * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1674 * enable wake-up power for it.
1675 */
1676 int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1677 {
1678 return pci_pme_capable(dev, PCI_D3cold) ?
1679 pci_enable_wake(dev, PCI_D3cold, enable) :
1680 pci_enable_wake(dev, PCI_D3hot, enable);
1681 }
1682
1683 /**
1684 * pci_target_state - find an appropriate low power state for a given PCI dev
1685 * @dev: PCI device
1686 *
1687 * Use underlying platform code to find a supported low power state for @dev.
1688 * If the platform can't manage @dev, return the deepest state from which it
1689 * can generate wake events, based on any available PME info.
1690 */
1691 pci_power_t pci_target_state(struct pci_dev *dev)
1692 {
1693 pci_power_t target_state = PCI_D3hot;
1694
1695 if (platform_pci_power_manageable(dev)) {
1696 /*
1697 * Call the platform to choose the target state of the device
1698 * and enable wake-up from this state if supported.
1699 */
1700 pci_power_t state = platform_pci_choose_state(dev);
1701
1702 switch (state) {
1703 case PCI_POWER_ERROR:
1704 case PCI_UNKNOWN:
1705 break;
1706 case PCI_D1:
1707 case PCI_D2:
1708 if (pci_no_d1d2(dev))
1709 break;
1710 default:
1711 target_state = state;
1712 }
1713 } else if (!dev->pm_cap) {
1714 target_state = PCI_D0;
1715 } else if (device_may_wakeup(&dev->dev)) {
1716 /*
1717 * Find the deepest state from which the device can generate
1718 * wake-up events, make it the target state and enable device
1719 * to generate PME#.
1720 */
1721 if (dev->pme_support) {
1722 while (target_state
1723 && !(dev->pme_support & (1 << target_state)))
1724 target_state--;
1725 }
1726 }
1727
1728 return target_state;
1729 }
1730
1731 /**
1732 * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1733 * @dev: Device to handle.
1734 *
1735 * Choose the power state appropriate for the device depending on whether
1736 * it can wake up the system and/or is power manageable by the platform
1737 * (PCI_D3hot is the default) and put the device into that state.
1738 */
1739 int pci_prepare_to_sleep(struct pci_dev *dev)
1740 {
1741 pci_power_t target_state = pci_target_state(dev);
1742 int error;
1743
1744 if (target_state == PCI_POWER_ERROR)
1745 return -EIO;
1746
1747 pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
1748
1749 error = pci_set_power_state(dev, target_state);
1750
1751 if (error)
1752 pci_enable_wake(dev, target_state, false);
1753
1754 return error;
1755 }
1756
1757 /**
1758 * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1759 * @dev: Device to handle.
1760 *
1761 * Disable device's system wake-up capability and put it into D0.
1762 */
1763 int pci_back_from_sleep(struct pci_dev *dev)
1764 {
1765 pci_enable_wake(dev, PCI_D0, false);
1766 return pci_set_power_state(dev, PCI_D0);
1767 }
1768
1769 /**
1770 * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend.
1771 * @dev: PCI device being suspended.
1772 *
1773 * Prepare @dev to generate wake-up events at run time and put it into a low
1774 * power state.
1775 */
1776 int pci_finish_runtime_suspend(struct pci_dev *dev)
1777 {
1778 pci_power_t target_state = pci_target_state(dev);
1779 int error;
1780
1781 if (target_state == PCI_POWER_ERROR)
1782 return -EIO;
1783
1784 __pci_enable_wake(dev, target_state, true, pci_dev_run_wake(dev));
1785
1786 error = pci_set_power_state(dev, target_state);
1787
1788 if (error)
1789 __pci_enable_wake(dev, target_state, true, false);
1790
1791 return error;
1792 }
1793
1794 /**
1795 * pci_dev_run_wake - Check if device can generate run-time wake-up events.
1796 * @dev: Device to check.
1797 *
1798 * Return true if the device itself is cabable of generating wake-up events
1799 * (through the platform or using the native PCIe PME) or if the device supports
1800 * PME and one of its upstream bridges can generate wake-up events.
1801 */
1802 bool pci_dev_run_wake(struct pci_dev *dev)
1803 {
1804 struct pci_bus *bus = dev->bus;
1805
1806 if (device_run_wake(&dev->dev))
1807 return true;
1808
1809 if (!dev->pme_support)
1810 return false;
1811
1812 while (bus->parent) {
1813 struct pci_dev *bridge = bus->self;
1814
1815 if (device_run_wake(&bridge->dev))
1816 return true;
1817
1818 bus = bus->parent;
1819 }
1820
1821 /* We have reached the root bus. */
1822 if (bus->bridge)
1823 return device_run_wake(bus->bridge);
1824
1825 return false;
1826 }
1827 EXPORT_SYMBOL_GPL(pci_dev_run_wake);
1828
1829 /**
1830 * pci_pm_init - Initialize PM functions of given PCI device
1831 * @dev: PCI device to handle.
1832 */
1833 void pci_pm_init(struct pci_dev *dev)
1834 {
1835 int pm;
1836 u16 pmc;
1837
1838 pm_runtime_forbid(&dev->dev);
1839 device_enable_async_suspend(&dev->dev);
1840 dev->wakeup_prepared = false;
1841
1842 dev->pm_cap = 0;
1843
1844 /* find PCI PM capability in list */
1845 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
1846 if (!pm)
1847 return;
1848 /* Check device's ability to generate PME# */
1849 pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
1850
1851 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
1852 dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
1853 pmc & PCI_PM_CAP_VER_MASK);
1854 return;
1855 }
1856
1857 dev->pm_cap = pm;
1858 dev->d3_delay = PCI_PM_D3_WAIT;
1859
1860 dev->d1_support = false;
1861 dev->d2_support = false;
1862 if (!pci_no_d1d2(dev)) {
1863 if (pmc & PCI_PM_CAP_D1)
1864 dev->d1_support = true;
1865 if (pmc & PCI_PM_CAP_D2)
1866 dev->d2_support = true;
1867
1868 if (dev->d1_support || dev->d2_support)
1869 dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
1870 dev->d1_support ? " D1" : "",
1871 dev->d2_support ? " D2" : "");
1872 }
1873
1874 pmc &= PCI_PM_CAP_PME_MASK;
1875 if (pmc) {
1876 dev_printk(KERN_DEBUG, &dev->dev,
1877 "PME# supported from%s%s%s%s%s\n",
1878 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
1879 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
1880 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
1881 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
1882 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
1883 dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
1884 dev->pme_poll = true;
1885 /*
1886 * Make device's PM flags reflect the wake-up capability, but
1887 * let the user space enable it to wake up the system as needed.
1888 */
1889 device_set_wakeup_capable(&dev->dev, true);
1890 /* Disable the PME# generation functionality */
1891 pci_pme_active(dev, false);
1892 } else {
1893 dev->pme_support = 0;
1894 }
1895 }
1896
1897 /**
1898 * platform_pci_wakeup_init - init platform wakeup if present
1899 * @dev: PCI device
1900 *
1901 * Some devices don't have PCI PM caps but can still generate wakeup
1902 * events through platform methods (like ACPI events). If @dev supports
1903 * platform wakeup events, set the device flag to indicate as much. This
1904 * may be redundant if the device also supports PCI PM caps, but double
1905 * initialization should be safe in that case.
1906 */
1907 void platform_pci_wakeup_init(struct pci_dev *dev)
1908 {
1909 if (!platform_pci_can_wakeup(dev))
1910 return;
1911
1912 device_set_wakeup_capable(&dev->dev, true);
1913 platform_pci_sleep_wake(dev, false);
1914 }
1915
1916 static void pci_add_saved_cap(struct pci_dev *pci_dev,
1917 struct pci_cap_saved_state *new_cap)
1918 {
1919 hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space);
1920 }
1921
1922 /**
1923 * pci_add_save_buffer - allocate buffer for saving given capability registers
1924 * @dev: the PCI device
1925 * @cap: the capability to allocate the buffer for
1926 * @size: requested size of the buffer
1927 */
1928 static int pci_add_cap_save_buffer(
1929 struct pci_dev *dev, char cap, unsigned int size)
1930 {
1931 int pos;
1932 struct pci_cap_saved_state *save_state;
1933
1934 pos = pci_find_capability(dev, cap);
1935 if (pos <= 0)
1936 return 0;
1937
1938 save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
1939 if (!save_state)
1940 return -ENOMEM;
1941
1942 save_state->cap.cap_nr = cap;
1943 save_state->cap.size = size;
1944 pci_add_saved_cap(dev, save_state);
1945
1946 return 0;
1947 }
1948
1949 /**
1950 * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
1951 * @dev: the PCI device
1952 */
1953 void pci_allocate_cap_save_buffers(struct pci_dev *dev)
1954 {
1955 int error;
1956
1957 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
1958 PCI_EXP_SAVE_REGS * sizeof(u16));
1959 if (error)
1960 dev_err(&dev->dev,
1961 "unable to preallocate PCI Express save buffer\n");
1962
1963 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
1964 if (error)
1965 dev_err(&dev->dev,
1966 "unable to preallocate PCI-X save buffer\n");
1967 }
1968
1969 void pci_free_cap_save_buffers(struct pci_dev *dev)
1970 {
1971 struct pci_cap_saved_state *tmp;
1972 struct hlist_node *pos, *n;
1973
1974 hlist_for_each_entry_safe(tmp, pos, n, &dev->saved_cap_space, next)
1975 kfree(tmp);
1976 }
1977
1978 /**
1979 * pci_enable_ari - enable ARI forwarding if hardware support it
1980 * @dev: the PCI device
1981 */
1982 void pci_enable_ari(struct pci_dev *dev)
1983 {
1984 int pos;
1985 u32 cap;
1986 u16 flags, ctrl;
1987 struct pci_dev *bridge;
1988
1989 if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn)
1990 return;
1991
1992 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1993 if (!pos)
1994 return;
1995
1996 bridge = dev->bus->self;
1997 if (!bridge || !pci_is_pcie(bridge))
1998 return;
1999
2000 pos = pci_pcie_cap(bridge);
2001 if (!pos)
2002 return;
2003
2004 /* ARI is a PCIe v2 feature */
2005 pci_read_config_word(bridge, pos + PCI_EXP_FLAGS, &flags);
2006 if ((flags & PCI_EXP_FLAGS_VERS) < 2)
2007 return;
2008
2009 pci_read_config_dword(bridge, pos + PCI_EXP_DEVCAP2, &cap);
2010 if (!(cap & PCI_EXP_DEVCAP2_ARI))
2011 return;
2012
2013 pci_read_config_word(bridge, pos + PCI_EXP_DEVCTL2, &ctrl);
2014 ctrl |= PCI_EXP_DEVCTL2_ARI;
2015 pci_write_config_word(bridge, pos + PCI_EXP_DEVCTL2, ctrl);
2016
2017 bridge->ari_enabled = 1;
2018 }
2019
2020 /**
2021 * pci_enable_ido - enable ID-based ordering on a device
2022 * @dev: the PCI device
2023 * @type: which types of IDO to enable
2024 *
2025 * Enable ID-based ordering on @dev. @type can contain the bits
2026 * %PCI_EXP_IDO_REQUEST and/or %PCI_EXP_IDO_COMPLETION to indicate
2027 * which types of transactions are allowed to be re-ordered.
2028 */
2029 void pci_enable_ido(struct pci_dev *dev, unsigned long type)
2030 {
2031 int pos;
2032 u16 ctrl;
2033
2034 pos = pci_pcie_cap(dev);
2035 if (!pos)
2036 return;
2037
2038 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
2039 if (type & PCI_EXP_IDO_REQUEST)
2040 ctrl |= PCI_EXP_IDO_REQ_EN;
2041 if (type & PCI_EXP_IDO_COMPLETION)
2042 ctrl |= PCI_EXP_IDO_CMP_EN;
2043 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
2044 }
2045 EXPORT_SYMBOL(pci_enable_ido);
2046
2047 /**
2048 * pci_disable_ido - disable ID-based ordering on a device
2049 * @dev: the PCI device
2050 * @type: which types of IDO to disable
2051 */
2052 void pci_disable_ido(struct pci_dev *dev, unsigned long type)
2053 {
2054 int pos;
2055 u16 ctrl;
2056
2057 if (!pci_is_pcie(dev))
2058 return;
2059
2060 pos = pci_pcie_cap(dev);
2061 if (!pos)
2062 return;
2063
2064 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
2065 if (type & PCI_EXP_IDO_REQUEST)
2066 ctrl &= ~PCI_EXP_IDO_REQ_EN;
2067 if (type & PCI_EXP_IDO_COMPLETION)
2068 ctrl &= ~PCI_EXP_IDO_CMP_EN;
2069 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
2070 }
2071 EXPORT_SYMBOL(pci_disable_ido);
2072
2073 /**
2074 * pci_enable_obff - enable optimized buffer flush/fill
2075 * @dev: PCI device
2076 * @type: type of signaling to use
2077 *
2078 * Try to enable @type OBFF signaling on @dev. It will try using WAKE#
2079 * signaling if possible, falling back to message signaling only if
2080 * WAKE# isn't supported. @type should indicate whether the PCIe link
2081 * be brought out of L0s or L1 to send the message. It should be either
2082 * %PCI_EXP_OBFF_SIGNAL_ALWAYS or %PCI_OBFF_SIGNAL_L0.
2083 *
2084 * If your device can benefit from receiving all messages, even at the
2085 * power cost of bringing the link back up from a low power state, use
2086 * %PCI_EXP_OBFF_SIGNAL_ALWAYS. Otherwise, use %PCI_OBFF_SIGNAL_L0 (the
2087 * preferred type).
2088 *
2089 * RETURNS:
2090 * Zero on success, appropriate error number on failure.
2091 */
2092 int pci_enable_obff(struct pci_dev *dev, enum pci_obff_signal_type type)
2093 {
2094 int pos;
2095 u32 cap;
2096 u16 ctrl;
2097 int ret;
2098
2099 if (!pci_is_pcie(dev))
2100 return -ENOTSUPP;
2101
2102 pos = pci_pcie_cap(dev);
2103 if (!pos)
2104 return -ENOTSUPP;
2105
2106 pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP2, &cap);
2107 if (!(cap & PCI_EXP_OBFF_MASK))
2108 return -ENOTSUPP; /* no OBFF support at all */
2109
2110 /* Make sure the topology supports OBFF as well */
2111 if (dev->bus) {
2112 ret = pci_enable_obff(dev->bus->self, type);
2113 if (ret)
2114 return ret;
2115 }
2116
2117 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
2118 if (cap & PCI_EXP_OBFF_WAKE)
2119 ctrl |= PCI_EXP_OBFF_WAKE_EN;
2120 else {
2121 switch (type) {
2122 case PCI_EXP_OBFF_SIGNAL_L0:
2123 if (!(ctrl & PCI_EXP_OBFF_WAKE_EN))
2124 ctrl |= PCI_EXP_OBFF_MSGA_EN;
2125 break;
2126 case PCI_EXP_OBFF_SIGNAL_ALWAYS:
2127 ctrl &= ~PCI_EXP_OBFF_WAKE_EN;
2128 ctrl |= PCI_EXP_OBFF_MSGB_EN;
2129 break;
2130 default:
2131 WARN(1, "bad OBFF signal type\n");
2132 return -ENOTSUPP;
2133 }
2134 }
2135 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
2136
2137 return 0;
2138 }
2139 EXPORT_SYMBOL(pci_enable_obff);
2140
2141 /**
2142 * pci_disable_obff - disable optimized buffer flush/fill
2143 * @dev: PCI device
2144 *
2145 * Disable OBFF on @dev.
2146 */
2147 void pci_disable_obff(struct pci_dev *dev)
2148 {
2149 int pos;
2150 u16 ctrl;
2151
2152 if (!pci_is_pcie(dev))
2153 return;
2154
2155 pos = pci_pcie_cap(dev);
2156 if (!pos)
2157 return;
2158
2159 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
2160 ctrl &= ~PCI_EXP_OBFF_WAKE_EN;
2161 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
2162 }
2163 EXPORT_SYMBOL(pci_disable_obff);
2164
2165 /**
2166 * pci_ltr_supported - check whether a device supports LTR
2167 * @dev: PCI device
2168 *
2169 * RETURNS:
2170 * True if @dev supports latency tolerance reporting, false otherwise.
2171 */
2172 bool pci_ltr_supported(struct pci_dev *dev)
2173 {
2174 int pos;
2175 u32 cap;
2176
2177 if (!pci_is_pcie(dev))
2178 return false;
2179
2180 pos = pci_pcie_cap(dev);
2181 if (!pos)
2182 return false;
2183
2184 pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP2, &cap);
2185
2186 return cap & PCI_EXP_DEVCAP2_LTR;
2187 }
2188 EXPORT_SYMBOL(pci_ltr_supported);
2189
2190 /**
2191 * pci_enable_ltr - enable latency tolerance reporting
2192 * @dev: PCI device
2193 *
2194 * Enable LTR on @dev if possible, which means enabling it first on
2195 * upstream ports.
2196 *
2197 * RETURNS:
2198 * Zero on success, errno on failure.
2199 */
2200 int pci_enable_ltr(struct pci_dev *dev)
2201 {
2202 int pos;
2203 u16 ctrl;
2204 int ret;
2205
2206 if (!pci_ltr_supported(dev))
2207 return -ENOTSUPP;
2208
2209 pos = pci_pcie_cap(dev);
2210 if (!pos)
2211 return -ENOTSUPP;
2212
2213 /* Only primary function can enable/disable LTR */
2214 if (PCI_FUNC(dev->devfn) != 0)
2215 return -EINVAL;
2216
2217 /* Enable upstream ports first */
2218 if (dev->bus) {
2219 ret = pci_enable_ltr(dev->bus->self);
2220 if (ret)
2221 return ret;
2222 }
2223
2224 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
2225 ctrl |= PCI_EXP_LTR_EN;
2226 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
2227
2228 return 0;
2229 }
2230 EXPORT_SYMBOL(pci_enable_ltr);
2231
2232 /**
2233 * pci_disable_ltr - disable latency tolerance reporting
2234 * @dev: PCI device
2235 */
2236 void pci_disable_ltr(struct pci_dev *dev)
2237 {
2238 int pos;
2239 u16 ctrl;
2240
2241 if (!pci_ltr_supported(dev))
2242 return;
2243
2244 pos = pci_pcie_cap(dev);
2245 if (!pos)
2246 return;
2247
2248 /* Only primary function can enable/disable LTR */
2249 if (PCI_FUNC(dev->devfn) != 0)
2250 return;
2251
2252 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
2253 ctrl &= ~PCI_EXP_LTR_EN;
2254 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
2255 }
2256 EXPORT_SYMBOL(pci_disable_ltr);
2257
2258 static int __pci_ltr_scale(int *val)
2259 {
2260 int scale = 0;
2261
2262 while (*val > 1023) {
2263 *val = (*val + 31) / 32;
2264 scale++;
2265 }
2266 return scale;
2267 }
2268
2269 /**
2270 * pci_set_ltr - set LTR latency values
2271 * @dev: PCI device
2272 * @snoop_lat_ns: snoop latency in nanoseconds
2273 * @nosnoop_lat_ns: nosnoop latency in nanoseconds
2274 *
2275 * Figure out the scale and set the LTR values accordingly.
2276 */
2277 int pci_set_ltr(struct pci_dev *dev, int snoop_lat_ns, int nosnoop_lat_ns)
2278 {
2279 int pos, ret, snoop_scale, nosnoop_scale;
2280 u16 val;
2281
2282 if (!pci_ltr_supported(dev))
2283 return -ENOTSUPP;
2284
2285 snoop_scale = __pci_ltr_scale(&snoop_lat_ns);
2286 nosnoop_scale = __pci_ltr_scale(&nosnoop_lat_ns);
2287
2288 if (snoop_lat_ns > PCI_LTR_VALUE_MASK ||
2289 nosnoop_lat_ns > PCI_LTR_VALUE_MASK)
2290 return -EINVAL;
2291
2292 if ((snoop_scale > (PCI_LTR_SCALE_MASK >> PCI_LTR_SCALE_SHIFT)) ||
2293 (nosnoop_scale > (PCI_LTR_SCALE_MASK >> PCI_LTR_SCALE_SHIFT)))
2294 return -EINVAL;
2295
2296 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_LTR);
2297 if (!pos)
2298 return -ENOTSUPP;
2299
2300 val = (snoop_scale << PCI_LTR_SCALE_SHIFT) | snoop_lat_ns;
2301 ret = pci_write_config_word(dev, pos + PCI_LTR_MAX_SNOOP_LAT, val);
2302 if (ret != 4)
2303 return -EIO;
2304
2305 val = (nosnoop_scale << PCI_LTR_SCALE_SHIFT) | nosnoop_lat_ns;
2306 ret = pci_write_config_word(dev, pos + PCI_LTR_MAX_NOSNOOP_LAT, val);
2307 if (ret != 4)
2308 return -EIO;
2309
2310 return 0;
2311 }
2312 EXPORT_SYMBOL(pci_set_ltr);
2313
2314 static int pci_acs_enable;
2315
2316 /**
2317 * pci_request_acs - ask for ACS to be enabled if supported
2318 */
2319 void pci_request_acs(void)
2320 {
2321 pci_acs_enable = 1;
2322 }
2323
2324 /**
2325 * pci_enable_acs - enable ACS if hardware support it
2326 * @dev: the PCI device
2327 */
2328 void pci_enable_acs(struct pci_dev *dev)
2329 {
2330 int pos;
2331 u16 cap;
2332 u16 ctrl;
2333
2334 if (!pci_acs_enable)
2335 return;
2336
2337 if (!pci_is_pcie(dev))
2338 return;
2339
2340 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
2341 if (!pos)
2342 return;
2343
2344 pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
2345 pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
2346
2347 /* Source Validation */
2348 ctrl |= (cap & PCI_ACS_SV);
2349
2350 /* P2P Request Redirect */
2351 ctrl |= (cap & PCI_ACS_RR);
2352
2353 /* P2P Completion Redirect */
2354 ctrl |= (cap & PCI_ACS_CR);
2355
2356 /* Upstream Forwarding */
2357 ctrl |= (cap & PCI_ACS_UF);
2358
2359 pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
2360 }
2361
2362 /**
2363 * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
2364 * @dev: the PCI device
2365 * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTD, 4=INTD)
2366 *
2367 * Perform INTx swizzling for a device behind one level of bridge. This is
2368 * required by section 9.1 of the PCI-to-PCI bridge specification for devices
2369 * behind bridges on add-in cards. For devices with ARI enabled, the slot
2370 * number is always 0 (see the Implementation Note in section 2.2.8.1 of
2371 * the PCI Express Base Specification, Revision 2.1)
2372 */
2373 u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin)
2374 {
2375 int slot;
2376
2377 if (pci_ari_enabled(dev->bus))
2378 slot = 0;
2379 else
2380 slot = PCI_SLOT(dev->devfn);
2381
2382 return (((pin - 1) + slot) % 4) + 1;
2383 }
2384
2385 int
2386 pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
2387 {
2388 u8 pin;
2389
2390 pin = dev->pin;
2391 if (!pin)
2392 return -1;
2393
2394 while (!pci_is_root_bus(dev->bus)) {
2395 pin = pci_swizzle_interrupt_pin(dev, pin);
2396 dev = dev->bus->self;
2397 }
2398 *bridge = dev;
2399 return pin;
2400 }
2401
2402 /**
2403 * pci_common_swizzle - swizzle INTx all the way to root bridge
2404 * @dev: the PCI device
2405 * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
2406 *
2407 * Perform INTx swizzling for a device. This traverses through all PCI-to-PCI
2408 * bridges all the way up to a PCI root bus.
2409 */
2410 u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
2411 {
2412 u8 pin = *pinp;
2413
2414 while (!pci_is_root_bus(dev->bus)) {
2415 pin = pci_swizzle_interrupt_pin(dev, pin);
2416 dev = dev->bus->self;
2417 }
2418 *pinp = pin;
2419 return PCI_SLOT(dev->devfn);
2420 }
2421
2422 /**
2423 * pci_release_region - Release a PCI bar
2424 * @pdev: PCI device whose resources were previously reserved by pci_request_region
2425 * @bar: BAR to release
2426 *
2427 * Releases the PCI I/O and memory resources previously reserved by a
2428 * successful call to pci_request_region. Call this function only
2429 * after all use of the PCI regions has ceased.
2430 */
2431 void pci_release_region(struct pci_dev *pdev, int bar)
2432 {
2433 struct pci_devres *dr;
2434
2435 if (pci_resource_len(pdev, bar) == 0)
2436 return;
2437 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
2438 release_region(pci_resource_start(pdev, bar),
2439 pci_resource_len(pdev, bar));
2440 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
2441 release_mem_region(pci_resource_start(pdev, bar),
2442 pci_resource_len(pdev, bar));
2443
2444 dr = find_pci_dr(pdev);
2445 if (dr)
2446 dr->region_mask &= ~(1 << bar);
2447 }
2448
2449 /**
2450 * __pci_request_region - Reserved PCI I/O and memory resource
2451 * @pdev: PCI device whose resources are to be reserved
2452 * @bar: BAR to be reserved
2453 * @res_name: Name to be associated with resource.
2454 * @exclusive: whether the region access is exclusive or not
2455 *
2456 * Mark the PCI region associated with PCI device @pdev BR @bar as
2457 * being reserved by owner @res_name. Do not access any
2458 * address inside the PCI regions unless this call returns
2459 * successfully.
2460 *
2461 * If @exclusive is set, then the region is marked so that userspace
2462 * is explicitly not allowed to map the resource via /dev/mem or
2463 * sysfs MMIO access.
2464 *
2465 * Returns 0 on success, or %EBUSY on error. A warning
2466 * message is also printed on failure.
2467 */
2468 static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
2469 int exclusive)
2470 {
2471 struct pci_devres *dr;
2472
2473 if (pci_resource_len(pdev, bar) == 0)
2474 return 0;
2475
2476 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
2477 if (!request_region(pci_resource_start(pdev, bar),
2478 pci_resource_len(pdev, bar), res_name))
2479 goto err_out;
2480 }
2481 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
2482 if (!__request_mem_region(pci_resource_start(pdev, bar),
2483 pci_resource_len(pdev, bar), res_name,
2484 exclusive))
2485 goto err_out;
2486 }
2487
2488 dr = find_pci_dr(pdev);
2489 if (dr)
2490 dr->region_mask |= 1 << bar;
2491
2492 return 0;
2493
2494 err_out:
2495 dev_warn(&pdev->dev, "BAR %d: can't reserve %pR\n", bar,
2496 &pdev->resource[bar]);
2497 return -EBUSY;
2498 }
2499
2500 /**
2501 * pci_request_region - Reserve PCI I/O and memory resource
2502 * @pdev: PCI device whose resources are to be reserved
2503 * @bar: BAR to be reserved
2504 * @res_name: Name to be associated with resource
2505 *
2506 * Mark the PCI region associated with PCI device @pdev BAR @bar as
2507 * being reserved by owner @res_name. Do not access any
2508 * address inside the PCI regions unless this call returns
2509 * successfully.
2510 *
2511 * Returns 0 on success, or %EBUSY on error. A warning
2512 * message is also printed on failure.
2513 */
2514 int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
2515 {
2516 return __pci_request_region(pdev, bar, res_name, 0);
2517 }
2518
2519 /**
2520 * pci_request_region_exclusive - Reserved PCI I/O and memory resource
2521 * @pdev: PCI device whose resources are to be reserved
2522 * @bar: BAR to be reserved
2523 * @res_name: Name to be associated with resource.
2524 *
2525 * Mark the PCI region associated with PCI device @pdev BR @bar as
2526 * being reserved by owner @res_name. Do not access any
2527 * address inside the PCI regions unless this call returns
2528 * successfully.
2529 *
2530 * Returns 0 on success, or %EBUSY on error. A warning
2531 * message is also printed on failure.
2532 *
2533 * The key difference that _exclusive makes it that userspace is
2534 * explicitly not allowed to map the resource via /dev/mem or
2535 * sysfs.
2536 */
2537 int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name)
2538 {
2539 return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
2540 }
2541 /**
2542 * pci_release_selected_regions - Release selected PCI I/O and memory resources
2543 * @pdev: PCI device whose resources were previously reserved
2544 * @bars: Bitmask of BARs to be released
2545 *
2546 * Release selected PCI I/O and memory resources previously reserved.
2547 * Call this function only after all use of the PCI regions has ceased.
2548 */
2549 void pci_release_selected_regions(struct pci_dev *pdev, int bars)
2550 {
2551 int i;
2552
2553 for (i = 0; i < 6; i++)
2554 if (bars & (1 << i))
2555 pci_release_region(pdev, i);
2556 }
2557
2558 int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
2559 const char *res_name, int excl)
2560 {
2561 int i;
2562
2563 for (i = 0; i < 6; i++)
2564 if (bars & (1 << i))
2565 if (__pci_request_region(pdev, i, res_name, excl))
2566 goto err_out;
2567 return 0;
2568
2569 err_out:
2570 while(--i >= 0)
2571 if (bars & (1 << i))
2572 pci_release_region(pdev, i);
2573
2574 return -EBUSY;
2575 }
2576
2577
2578 /**
2579 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
2580 * @pdev: PCI device whose resources are to be reserved
2581 * @bars: Bitmask of BARs to be requested
2582 * @res_name: Name to be associated with resource
2583 */
2584 int pci_request_selected_regions(struct pci_dev *pdev, int bars,
2585 const char *res_name)
2586 {
2587 return __pci_request_selected_regions(pdev, bars, res_name, 0);
2588 }
2589
2590 int pci_request_selected_regions_exclusive(struct pci_dev *pdev,
2591 int bars, const char *res_name)
2592 {
2593 return __pci_request_selected_regions(pdev, bars, res_name,
2594 IORESOURCE_EXCLUSIVE);
2595 }
2596
2597 /**
2598 * pci_release_regions - Release reserved PCI I/O and memory resources
2599 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
2600 *
2601 * Releases all PCI I/O and memory resources previously reserved by a
2602 * successful call to pci_request_regions. Call this function only
2603 * after all use of the PCI regions has ceased.
2604 */
2605
2606 void pci_release_regions(struct pci_dev *pdev)
2607 {
2608 pci_release_selected_regions(pdev, (1 << 6) - 1);
2609 }
2610
2611 /**
2612 * pci_request_regions - Reserved PCI I/O and memory resources
2613 * @pdev: PCI device whose resources are to be reserved
2614 * @res_name: Name to be associated with resource.
2615 *
2616 * Mark all PCI regions associated with PCI device @pdev as
2617 * being reserved by owner @res_name. Do not access any
2618 * address inside the PCI regions unless this call returns
2619 * successfully.
2620 *
2621 * Returns 0 on success, or %EBUSY on error. A warning
2622 * message is also printed on failure.
2623 */
2624 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
2625 {
2626 return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
2627 }
2628
2629 /**
2630 * pci_request_regions_exclusive - Reserved PCI I/O and memory resources
2631 * @pdev: PCI device whose resources are to be reserved
2632 * @res_name: Name to be associated with resource.
2633 *
2634 * Mark all PCI regions associated with PCI device @pdev as
2635 * being reserved by owner @res_name. Do not access any
2636 * address inside the PCI regions unless this call returns
2637 * successfully.
2638 *
2639 * pci_request_regions_exclusive() will mark the region so that
2640 * /dev/mem and the sysfs MMIO access will not be allowed.
2641 *
2642 * Returns 0 on success, or %EBUSY on error. A warning
2643 * message is also printed on failure.
2644 */
2645 int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
2646 {
2647 return pci_request_selected_regions_exclusive(pdev,
2648 ((1 << 6) - 1), res_name);
2649 }
2650
2651 static void __pci_set_master(struct pci_dev *dev, bool enable)
2652 {
2653 u16 old_cmd, cmd;
2654
2655 pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
2656 if (enable)
2657 cmd = old_cmd | PCI_COMMAND_MASTER;
2658 else
2659 cmd = old_cmd & ~PCI_COMMAND_MASTER;
2660 if (cmd != old_cmd) {
2661 dev_dbg(&dev->dev, "%s bus mastering\n",
2662 enable ? "enabling" : "disabling");
2663 pci_write_config_word(dev, PCI_COMMAND, cmd);
2664 }
2665 dev->is_busmaster = enable;
2666 }
2667
2668 /**
2669 * pcibios_setup - process "pci=" kernel boot arguments
2670 * @str: string used to pass in "pci=" kernel boot arguments
2671 *
2672 * Process kernel boot arguments. This is the default implementation.
2673 * Architecture specific implementations can override this as necessary.
2674 */
2675 char * __weak __init pcibios_setup(char *str)
2676 {
2677 return str;
2678 }
2679
2680 /**
2681 * pcibios_set_master - enable PCI bus-mastering for device dev
2682 * @dev: the PCI device to enable
2683 *
2684 * Enables PCI bus-mastering for the device. This is the default
2685 * implementation. Architecture specific implementations can override
2686 * this if necessary.
2687 */
2688 void __weak pcibios_set_master(struct pci_dev *dev)
2689 {
2690 u8 lat;
2691
2692 /* The latency timer doesn't apply to PCIe (either Type 0 or Type 1) */
2693 if (pci_is_pcie(dev))
2694 return;
2695
2696 pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
2697 if (lat < 16)
2698 lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
2699 else if (lat > pcibios_max_latency)
2700 lat = pcibios_max_latency;
2701 else
2702 return;
2703 dev_printk(KERN_DEBUG, &dev->dev, "setting latency timer to %d\n", lat);
2704 pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
2705 }
2706
2707 /**
2708 * pci_set_master - enables bus-mastering for device dev
2709 * @dev: the PCI device to enable
2710 *
2711 * Enables bus-mastering on the device and calls pcibios_set_master()
2712 * to do the needed arch specific settings.
2713 */
2714 void pci_set_master(struct pci_dev *dev)
2715 {
2716 __pci_set_master(dev, true);
2717 pcibios_set_master(dev);
2718 }
2719
2720 /**
2721 * pci_clear_master - disables bus-mastering for device dev
2722 * @dev: the PCI device to disable
2723 */
2724 void pci_clear_master(struct pci_dev *dev)
2725 {
2726 __pci_set_master(dev, false);
2727 }
2728
2729 /**
2730 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
2731 * @dev: the PCI device for which MWI is to be enabled
2732 *
2733 * Helper function for pci_set_mwi.
2734 * Originally copied from drivers/net/acenic.c.
2735 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
2736 *
2737 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2738 */
2739 int pci_set_cacheline_size(struct pci_dev *dev)
2740 {
2741 u8 cacheline_size;
2742
2743 if (!pci_cache_line_size)
2744 return -EINVAL;
2745
2746 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
2747 equal to or multiple of the right value. */
2748 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2749 if (cacheline_size >= pci_cache_line_size &&
2750 (cacheline_size % pci_cache_line_size) == 0)
2751 return 0;
2752
2753 /* Write the correct value. */
2754 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
2755 /* Read it back. */
2756 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2757 if (cacheline_size == pci_cache_line_size)
2758 return 0;
2759
2760 dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
2761 "supported\n", pci_cache_line_size << 2);
2762
2763 return -EINVAL;
2764 }
2765 EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
2766
2767 #ifdef PCI_DISABLE_MWI
2768 int pci_set_mwi(struct pci_dev *dev)
2769 {
2770 return 0;
2771 }
2772
2773 int pci_try_set_mwi(struct pci_dev *dev)
2774 {
2775 return 0;
2776 }
2777
2778 void pci_clear_mwi(struct pci_dev *dev)
2779 {
2780 }
2781
2782 #else
2783
2784 /**
2785 * pci_set_mwi - enables memory-write-invalidate PCI transaction
2786 * @dev: the PCI device for which MWI is enabled
2787 *
2788 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2789 *
2790 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2791 */
2792 int
2793 pci_set_mwi(struct pci_dev *dev)
2794 {
2795 int rc;
2796 u16 cmd;
2797
2798 rc = pci_set_cacheline_size(dev);
2799 if (rc)
2800 return rc;
2801
2802 pci_read_config_word(dev, PCI_COMMAND, &cmd);
2803 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
2804 dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
2805 cmd |= PCI_COMMAND_INVALIDATE;
2806 pci_write_config_word(dev, PCI_COMMAND, cmd);
2807 }
2808
2809 return 0;
2810 }
2811
2812 /**
2813 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
2814 * @dev: the PCI device for which MWI is enabled
2815 *
2816 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2817 * Callers are not required to check the return value.
2818 *
2819 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2820 */
2821 int pci_try_set_mwi(struct pci_dev *dev)
2822 {
2823 int rc = pci_set_mwi(dev);
2824 return rc;
2825 }
2826
2827 /**
2828 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
2829 * @dev: the PCI device to disable
2830 *
2831 * Disables PCI Memory-Write-Invalidate transaction on the device
2832 */
2833 void
2834 pci_clear_mwi(struct pci_dev *dev)
2835 {
2836 u16 cmd;
2837
2838 pci_read_config_word(dev, PCI_COMMAND, &cmd);
2839 if (cmd & PCI_COMMAND_INVALIDATE) {
2840 cmd &= ~PCI_COMMAND_INVALIDATE;
2841 pci_write_config_word(dev, PCI_COMMAND, cmd);
2842 }
2843 }
2844 #endif /* ! PCI_DISABLE_MWI */
2845
2846 /**
2847 * pci_intx - enables/disables PCI INTx for device dev
2848 * @pdev: the PCI device to operate on
2849 * @enable: boolean: whether to enable or disable PCI INTx
2850 *
2851 * Enables/disables PCI INTx for device dev
2852 */
2853 void
2854 pci_intx(struct pci_dev *pdev, int enable)
2855 {
2856 u16 pci_command, new;
2857
2858 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
2859
2860 if (enable) {
2861 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
2862 } else {
2863 new = pci_command | PCI_COMMAND_INTX_DISABLE;
2864 }
2865
2866 if (new != pci_command) {
2867 struct pci_devres *dr;
2868
2869 pci_write_config_word(pdev, PCI_COMMAND, new);
2870
2871 dr = find_pci_dr(pdev);
2872 if (dr && !dr->restore_intx) {
2873 dr->restore_intx = 1;
2874 dr->orig_intx = !enable;
2875 }
2876 }
2877 }
2878
2879 /**
2880 * pci_intx_mask_supported - probe for INTx masking support
2881 * @dev: the PCI device to operate on
2882 *
2883 * Check if the device dev support INTx masking via the config space
2884 * command word.
2885 */
2886 bool pci_intx_mask_supported(struct pci_dev *dev)
2887 {
2888 bool mask_supported = false;
2889 u16 orig, new;
2890
2891 pci_cfg_access_lock(dev);
2892
2893 pci_read_config_word(dev, PCI_COMMAND, &orig);
2894 pci_write_config_word(dev, PCI_COMMAND,
2895 orig ^ PCI_COMMAND_INTX_DISABLE);
2896 pci_read_config_word(dev, PCI_COMMAND, &new);
2897
2898 /*
2899 * There's no way to protect against hardware bugs or detect them
2900 * reliably, but as long as we know what the value should be, let's
2901 * go ahead and check it.
2902 */
2903 if ((new ^ orig) & ~PCI_COMMAND_INTX_DISABLE) {
2904 dev_err(&dev->dev, "Command register changed from "
2905 "0x%x to 0x%x: driver or hardware bug?\n", orig, new);
2906 } else if ((new ^ orig) & PCI_COMMAND_INTX_DISABLE) {
2907 mask_supported = true;
2908 pci_write_config_word(dev, PCI_COMMAND, orig);
2909 }
2910
2911 pci_cfg_access_unlock(dev);
2912 return mask_supported;
2913 }
2914 EXPORT_SYMBOL_GPL(pci_intx_mask_supported);
2915
2916 static bool pci_check_and_set_intx_mask(struct pci_dev *dev, bool mask)
2917 {
2918 struct pci_bus *bus = dev->bus;
2919 bool mask_updated = true;
2920 u32 cmd_status_dword;
2921 u16 origcmd, newcmd;
2922 unsigned long flags;
2923 bool irq_pending;
2924
2925 /*
2926 * We do a single dword read to retrieve both command and status.
2927 * Document assumptions that make this possible.
2928 */
2929 BUILD_BUG_ON(PCI_COMMAND % 4);
2930 BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
2931
2932 raw_spin_lock_irqsave(&pci_lock, flags);
2933
2934 bus->ops->read(bus, dev->devfn, PCI_COMMAND, 4, &cmd_status_dword);
2935
2936 irq_pending = (cmd_status_dword >> 16) & PCI_STATUS_INTERRUPT;
2937
2938 /*
2939 * Check interrupt status register to see whether our device
2940 * triggered the interrupt (when masking) or the next IRQ is
2941 * already pending (when unmasking).
2942 */
2943 if (mask != irq_pending) {
2944 mask_updated = false;
2945 goto done;
2946 }
2947
2948 origcmd = cmd_status_dword;
2949 newcmd = origcmd & ~PCI_COMMAND_INTX_DISABLE;
2950 if (mask)
2951 newcmd |= PCI_COMMAND_INTX_DISABLE;
2952 if (newcmd != origcmd)
2953 bus->ops->write(bus, dev->devfn, PCI_COMMAND, 2, newcmd);
2954
2955 done:
2956 raw_spin_unlock_irqrestore(&pci_lock, flags);
2957
2958 return mask_updated;
2959 }
2960
2961 /**
2962 * pci_check_and_mask_intx - mask INTx on pending interrupt
2963 * @dev: the PCI device to operate on
2964 *
2965 * Check if the device dev has its INTx line asserted, mask it and
2966 * return true in that case. False is returned if not interrupt was
2967 * pending.
2968 */
2969 bool pci_check_and_mask_intx(struct pci_dev *dev)
2970 {
2971 return pci_check_and_set_intx_mask(dev, true);
2972 }
2973 EXPORT_SYMBOL_GPL(pci_check_and_mask_intx);
2974
2975 /**
2976 * pci_check_and_mask_intx - unmask INTx of no interrupt is pending
2977 * @dev: the PCI device to operate on
2978 *
2979 * Check if the device dev has its INTx line asserted, unmask it if not
2980 * and return true. False is returned and the mask remains active if
2981 * there was still an interrupt pending.
2982 */
2983 bool pci_check_and_unmask_intx(struct pci_dev *dev)
2984 {
2985 return pci_check_and_set_intx_mask(dev, false);
2986 }
2987 EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx);
2988
2989 /**
2990 * pci_msi_off - disables any msi or msix capabilities
2991 * @dev: the PCI device to operate on
2992 *
2993 * If you want to use msi see pci_enable_msi and friends.
2994 * This is a lower level primitive that allows us to disable
2995 * msi operation at the device level.
2996 */
2997 void pci_msi_off(struct pci_dev *dev)
2998 {
2999 int pos;
3000 u16 control;
3001
3002 pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
3003 if (pos) {
3004 pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
3005 control &= ~PCI_MSI_FLAGS_ENABLE;
3006 pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
3007 }
3008 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
3009 if (pos) {
3010 pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
3011 control &= ~PCI_MSIX_FLAGS_ENABLE;
3012 pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
3013 }
3014 }
3015 EXPORT_SYMBOL_GPL(pci_msi_off);
3016
3017 int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
3018 {
3019 return dma_set_max_seg_size(&dev->dev, size);
3020 }
3021 EXPORT_SYMBOL(pci_set_dma_max_seg_size);
3022
3023 int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
3024 {
3025 return dma_set_seg_boundary(&dev->dev, mask);
3026 }
3027 EXPORT_SYMBOL(pci_set_dma_seg_boundary);
3028
3029 static int pcie_flr(struct pci_dev *dev, int probe)
3030 {
3031 int i;
3032 int pos;
3033 u32 cap;
3034 u16 status, control;
3035
3036 pos = pci_pcie_cap(dev);
3037 if (!pos)
3038 return -ENOTTY;
3039
3040 pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP, &cap);
3041 if (!(cap & PCI_EXP_DEVCAP_FLR))
3042 return -ENOTTY;
3043
3044 if (probe)
3045 return 0;
3046
3047 /* Wait for Transaction Pending bit clean */
3048 for (i = 0; i < 4; i++) {
3049 if (i)
3050 msleep((1 << (i - 1)) * 100);
3051
3052 pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &status);
3053 if (!(status & PCI_EXP_DEVSTA_TRPND))
3054 goto clear;
3055 }
3056
3057 dev_err(&dev->dev, "transaction is not cleared; "
3058 "proceeding with reset anyway\n");
3059
3060 clear:
3061 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &control);
3062 control |= PCI_EXP_DEVCTL_BCR_FLR;
3063 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, control);
3064
3065 msleep(100);
3066
3067 return 0;
3068 }
3069
3070 static int pci_af_flr(struct pci_dev *dev, int probe)
3071 {
3072 int i;
3073 int pos;
3074 u8 cap;
3075 u8 status;
3076
3077 pos = pci_find_capability(dev, PCI_CAP_ID_AF);
3078 if (!pos)
3079 return -ENOTTY;
3080
3081 pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
3082 if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
3083 return -ENOTTY;
3084
3085 if (probe)
3086 return 0;
3087
3088 /* Wait for Transaction Pending bit clean */
3089 for (i = 0; i < 4; i++) {
3090 if (i)
3091 msleep((1 << (i - 1)) * 100);
3092
3093 pci_read_config_byte(dev, pos + PCI_AF_STATUS, &status);
3094 if (!(status & PCI_AF_STATUS_TP))
3095 goto clear;
3096 }
3097
3098 dev_err(&dev->dev, "transaction is not cleared; "
3099 "proceeding with reset anyway\n");
3100
3101 clear:
3102 pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
3103 msleep(100);
3104
3105 return 0;
3106 }
3107
3108 /**
3109 * pci_pm_reset - Put device into PCI_D3 and back into PCI_D0.
3110 * @dev: Device to reset.
3111 * @probe: If set, only check if the device can be reset this way.
3112 *
3113 * If @dev supports native PCI PM and its PCI_PM_CTRL_NO_SOFT_RESET flag is
3114 * unset, it will be reinitialized internally when going from PCI_D3hot to
3115 * PCI_D0. If that's the case and the device is not in a low-power state
3116 * already, force it into PCI_D3hot and back to PCI_D0, causing it to be reset.
3117 *
3118 * NOTE: This causes the caller to sleep for twice the device power transition
3119 * cooldown period, which for the D0->D3hot and D3hot->D0 transitions is 10 ms
3120 * by devault (i.e. unless the @dev's d3_delay field has a different value).
3121 * Moreover, only devices in D0 can be reset by this function.
3122 */
3123 static int pci_pm_reset(struct pci_dev *dev, int probe)
3124 {
3125 u16 csr;
3126
3127 if (!dev->pm_cap)
3128 return -ENOTTY;
3129
3130 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
3131 if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
3132 return -ENOTTY;
3133
3134 if (probe)
3135 return 0;
3136
3137 if (dev->current_state != PCI_D0)
3138 return -EINVAL;
3139
3140 csr &= ~PCI_PM_CTRL_STATE_MASK;
3141 csr |= PCI_D3hot;
3142 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
3143 pci_dev_d3_sleep(dev);
3144
3145 csr &= ~PCI_PM_CTRL_STATE_MASK;
3146 csr |= PCI_D0;
3147 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
3148 pci_dev_d3_sleep(dev);
3149
3150 return 0;
3151 }
3152
3153 static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
3154 {
3155 u16 ctrl;
3156 struct pci_dev *pdev;
3157
3158 if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self)
3159 return -ENOTTY;
3160
3161 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
3162 if (pdev != dev)
3163 return -ENOTTY;
3164
3165 if (probe)
3166 return 0;
3167
3168 pci_read_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, &ctrl);
3169 ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
3170 pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
3171 msleep(100);
3172
3173 ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
3174 pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
3175 msleep(100);
3176
3177 return 0;
3178 }
3179
3180 static int __pci_dev_reset(struct pci_dev *dev, int probe)
3181 {
3182 int rc;
3183
3184 might_sleep();
3185
3186 rc = pci_dev_specific_reset(dev, probe);
3187 if (rc != -ENOTTY)
3188 goto done;
3189
3190 rc = pcie_flr(dev, probe);
3191 if (rc != -ENOTTY)
3192 goto done;
3193
3194 rc = pci_af_flr(dev, probe);
3195 if (rc != -ENOTTY)
3196 goto done;
3197
3198 rc = pci_pm_reset(dev, probe);
3199 if (rc != -ENOTTY)
3200 goto done;
3201
3202 rc = pci_parent_bus_reset(dev, probe);
3203 done:
3204 return rc;
3205 }
3206
3207 static int pci_dev_reset(struct pci_dev *dev, int probe)
3208 {
3209 int rc;
3210
3211 if (!probe) {
3212 pci_cfg_access_lock(dev);
3213 /* block PM suspend, driver probe, etc. */
3214 device_lock(&dev->dev);
3215 }
3216
3217 rc = __pci_dev_reset(dev, probe);
3218
3219 if (!probe) {
3220 device_unlock(&dev->dev);
3221 pci_cfg_access_unlock(dev);
3222 }
3223 return rc;
3224 }
3225 /**
3226 * __pci_reset_function - reset a PCI device function
3227 * @dev: PCI device to reset
3228 *
3229 * Some devices allow an individual function to be reset without affecting
3230 * other functions in the same device. The PCI device must be responsive
3231 * to PCI config space in order to use this function.
3232 *
3233 * The device function is presumed to be unused when this function is called.
3234 * Resetting the device will make the contents of PCI configuration space
3235 * random, so any caller of this must be prepared to reinitialise the
3236 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
3237 * etc.
3238 *
3239 * Returns 0 if the device function was successfully reset or negative if the
3240 * device doesn't support resetting a single function.
3241 */
3242 int __pci_reset_function(struct pci_dev *dev)
3243 {
3244 return pci_dev_reset(dev, 0);
3245 }
3246 EXPORT_SYMBOL_GPL(__pci_reset_function);
3247
3248 /**
3249 * __pci_reset_function_locked - reset a PCI device function while holding
3250 * the @dev mutex lock.
3251 * @dev: PCI device to reset
3252 *
3253 * Some devices allow an individual function to be reset without affecting
3254 * other functions in the same device. The PCI device must be responsive
3255 * to PCI config space in order to use this function.
3256 *
3257 * The device function is presumed to be unused and the caller is holding
3258 * the device mutex lock when this function is called.
3259 * Resetting the device will make the contents of PCI configuration space
3260 * random, so any caller of this must be prepared to reinitialise the
3261 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
3262 * etc.
3263 *
3264 * Returns 0 if the device function was successfully reset or negative if the
3265 * device doesn't support resetting a single function.
3266 */
3267 int __pci_reset_function_locked(struct pci_dev *dev)
3268 {
3269 return __pci_dev_reset(dev, 0);
3270 }
3271 EXPORT_SYMBOL_GPL(__pci_reset_function_locked);
3272
3273 /**
3274 * pci_probe_reset_function - check whether the device can be safely reset
3275 * @dev: PCI device to reset
3276 *
3277 * Some devices allow an individual function to be reset without affecting
3278 * other functions in the same device. The PCI device must be responsive
3279 * to PCI config space in order to use this function.
3280 *
3281 * Returns 0 if the device function can be reset or negative if the
3282 * device doesn't support resetting a single function.
3283 */
3284 int pci_probe_reset_function(struct pci_dev *dev)
3285 {
3286 return pci_dev_reset(dev, 1);
3287 }
3288
3289 /**
3290 * pci_reset_function - quiesce and reset a PCI device function
3291 * @dev: PCI device to reset
3292 *
3293 * Some devices allow an individual function to be reset without affecting
3294 * other functions in the same device. The PCI device must be responsive
3295 * to PCI config space in order to use this function.
3296 *
3297 * This function does not just reset the PCI portion of a device, but
3298 * clears all the state associated with the device. This function differs
3299 * from __pci_reset_function in that it saves and restores device state
3300 * over the reset.
3301 *
3302 * Returns 0 if the device function was successfully reset or negative if the
3303 * device doesn't support resetting a single function.
3304 */
3305 int pci_reset_function(struct pci_dev *dev)
3306 {
3307 int rc;
3308
3309 rc = pci_dev_reset(dev, 1);
3310 if (rc)
3311 return rc;
3312
3313 pci_save_state(dev);
3314
3315 /*
3316 * both INTx and MSI are disabled after the Interrupt Disable bit
3317 * is set and the Bus Master bit is cleared.
3318 */
3319 pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
3320
3321 rc = pci_dev_reset(dev, 0);
3322
3323 pci_restore_state(dev);
3324
3325 return rc;
3326 }
3327 EXPORT_SYMBOL_GPL(pci_reset_function);
3328
3329 /**
3330 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
3331 * @dev: PCI device to query
3332 *
3333 * Returns mmrbc: maximum designed memory read count in bytes
3334 * or appropriate error value.
3335 */
3336 int pcix_get_max_mmrbc(struct pci_dev *dev)
3337 {
3338 int cap;
3339 u32 stat;
3340
3341 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3342 if (!cap)
3343 return -EINVAL;
3344
3345 if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
3346 return -EINVAL;
3347
3348 return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21);
3349 }
3350 EXPORT_SYMBOL(pcix_get_max_mmrbc);
3351
3352 /**
3353 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
3354 * @dev: PCI device to query
3355 *
3356 * Returns mmrbc: maximum memory read count in bytes
3357 * or appropriate error value.
3358 */
3359 int pcix_get_mmrbc(struct pci_dev *dev)
3360 {
3361 int cap;
3362 u16 cmd;
3363
3364 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3365 if (!cap)
3366 return -EINVAL;
3367
3368 if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
3369 return -EINVAL;
3370
3371 return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
3372 }
3373 EXPORT_SYMBOL(pcix_get_mmrbc);
3374
3375 /**
3376 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
3377 * @dev: PCI device to query
3378 * @mmrbc: maximum memory read count in bytes
3379 * valid values are 512, 1024, 2048, 4096
3380 *
3381 * If possible sets maximum memory read byte count, some bridges have erratas
3382 * that prevent this.
3383 */
3384 int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
3385 {
3386 int cap;
3387 u32 stat, v, o;
3388 u16 cmd;
3389
3390 if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
3391 return -EINVAL;
3392
3393 v = ffs(mmrbc) - 10;
3394
3395 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3396 if (!cap)
3397 return -EINVAL;
3398
3399 if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
3400 return -EINVAL;
3401
3402 if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
3403 return -E2BIG;
3404
3405 if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
3406 return -EINVAL;
3407
3408 o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
3409 if (o != v) {
3410 if (v > o && dev->bus &&
3411 (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
3412 return -EIO;
3413
3414 cmd &= ~PCI_X_CMD_MAX_READ;
3415 cmd |= v << 2;
3416 if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd))
3417 return -EIO;
3418 }
3419 return 0;
3420 }
3421 EXPORT_SYMBOL(pcix_set_mmrbc);
3422
3423 /**
3424 * pcie_get_readrq - get PCI Express read request size
3425 * @dev: PCI device to query
3426 *
3427 * Returns maximum memory read request in bytes
3428 * or appropriate error value.
3429 */
3430 int pcie_get_readrq(struct pci_dev *dev)
3431 {
3432 int ret, cap;
3433 u16 ctl;
3434
3435 cap = pci_pcie_cap(dev);
3436 if (!cap)
3437 return -EINVAL;
3438
3439 ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
3440 if (!ret)
3441 ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
3442
3443 return ret;
3444 }
3445 EXPORT_SYMBOL(pcie_get_readrq);
3446
3447 /**
3448 * pcie_set_readrq - set PCI Express maximum memory read request
3449 * @dev: PCI device to query
3450 * @rq: maximum memory read count in bytes
3451 * valid values are 128, 256, 512, 1024, 2048, 4096
3452 *
3453 * If possible sets maximum memory read request in bytes
3454 */
3455 int pcie_set_readrq(struct pci_dev *dev, int rq)
3456 {
3457 int cap, err = -EINVAL;
3458 u16 ctl, v;
3459
3460 if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
3461 goto out;
3462
3463 cap = pci_pcie_cap(dev);
3464 if (!cap)
3465 goto out;
3466
3467 err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
3468 if (err)
3469 goto out;
3470 /*
3471 * If using the "performance" PCIe config, we clamp the
3472 * read rq size to the max packet size to prevent the
3473 * host bridge generating requests larger than we can
3474 * cope with
3475 */
3476 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
3477 int mps = pcie_get_mps(dev);
3478
3479 if (mps < 0)
3480 return mps;
3481 if (mps < rq)
3482 rq = mps;
3483 }
3484
3485 v = (ffs(rq) - 8) << 12;
3486
3487 if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
3488 ctl &= ~PCI_EXP_DEVCTL_READRQ;
3489 ctl |= v;
3490 err = pci_write_config_word(dev, cap + PCI_EXP_DEVCTL, ctl);
3491 }
3492
3493 out:
3494 return err;
3495 }
3496 EXPORT_SYMBOL(pcie_set_readrq);
3497
3498 /**
3499 * pcie_get_mps - get PCI Express maximum payload size
3500 * @dev: PCI device to query
3501 *
3502 * Returns maximum payload size in bytes
3503 * or appropriate error value.
3504 */
3505 int pcie_get_mps(struct pci_dev *dev)
3506 {
3507 int ret, cap;
3508 u16 ctl;
3509
3510 cap = pci_pcie_cap(dev);
3511 if (!cap)
3512 return -EINVAL;
3513
3514 ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
3515 if (!ret)
3516 ret = 128 << ((ctl & PCI_EXP_DEVCTL_PAYLOAD) >> 5);
3517
3518 return ret;
3519 }
3520
3521 /**
3522 * pcie_set_mps - set PCI Express maximum payload size
3523 * @dev: PCI device to query
3524 * @mps: maximum payload size in bytes
3525 * valid values are 128, 256, 512, 1024, 2048, 4096
3526 *
3527 * If possible sets maximum payload size
3528 */
3529 int pcie_set_mps(struct pci_dev *dev, int mps)
3530 {
3531 int cap, err = -EINVAL;
3532 u16 ctl, v;
3533
3534 if (mps < 128 || mps > 4096 || !is_power_of_2(mps))
3535 goto out;
3536
3537 v = ffs(mps) - 8;
3538 if (v > dev->pcie_mpss)
3539 goto out;
3540 v <<= 5;
3541
3542 cap = pci_pcie_cap(dev);
3543 if (!cap)
3544 goto out;
3545
3546 err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
3547 if (err)
3548 goto out;
3549
3550 if ((ctl & PCI_EXP_DEVCTL_PAYLOAD) != v) {
3551 ctl &= ~PCI_EXP_DEVCTL_PAYLOAD;
3552 ctl |= v;
3553 err = pci_write_config_word(dev, cap + PCI_EXP_DEVCTL, ctl);
3554 }
3555 out:
3556 return err;
3557 }
3558
3559 /**
3560 * pci_select_bars - Make BAR mask from the type of resource
3561 * @dev: the PCI device for which BAR mask is made
3562 * @flags: resource type mask to be selected
3563 *
3564 * This helper routine makes bar mask from the type of resource.
3565 */
3566 int pci_select_bars(struct pci_dev *dev, unsigned long flags)
3567 {
3568 int i, bars = 0;
3569 for (i = 0; i < PCI_NUM_RESOURCES; i++)
3570 if (pci_resource_flags(dev, i) & flags)
3571 bars |= (1 << i);
3572 return bars;
3573 }
3574
3575 /**
3576 * pci_resource_bar - get position of the BAR associated with a resource
3577 * @dev: the PCI device
3578 * @resno: the resource number
3579 * @type: the BAR type to be filled in
3580 *
3581 * Returns BAR position in config space, or 0 if the BAR is invalid.
3582 */
3583 int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type)
3584 {
3585 int reg;
3586
3587 if (resno < PCI_ROM_RESOURCE) {
3588 *type = pci_bar_unknown;
3589 return PCI_BASE_ADDRESS_0 + 4 * resno;
3590 } else if (resno == PCI_ROM_RESOURCE) {
3591 *type = pci_bar_mem32;
3592 return dev->rom_base_reg;
3593 } else if (resno < PCI_BRIDGE_RESOURCES) {
3594 /* device specific resource */
3595 reg = pci_iov_resource_bar(dev, resno, type);
3596 if (reg)
3597 return reg;
3598 }
3599
3600 dev_err(&dev->dev, "BAR %d: invalid resource\n", resno);
3601 return 0;
3602 }
3603
3604 /* Some architectures require additional programming to enable VGA */
3605 static arch_set_vga_state_t arch_set_vga_state;
3606
3607 void __init pci_register_set_vga_state(arch_set_vga_state_t func)
3608 {
3609 arch_set_vga_state = func; /* NULL disables */
3610 }
3611
3612 static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode,
3613 unsigned int command_bits, u32 flags)
3614 {
3615 if (arch_set_vga_state)
3616 return arch_set_vga_state(dev, decode, command_bits,
3617 flags);
3618 return 0;
3619 }
3620
3621 /**
3622 * pci_set_vga_state - set VGA decode state on device and parents if requested
3623 * @dev: the PCI device
3624 * @decode: true = enable decoding, false = disable decoding
3625 * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
3626 * @flags: traverse ancestors and change bridges
3627 * CHANGE_BRIDGE_ONLY / CHANGE_BRIDGE
3628 */
3629 int pci_set_vga_state(struct pci_dev *dev, bool decode,
3630 unsigned int command_bits, u32 flags)
3631 {
3632 struct pci_bus *bus;
3633 struct pci_dev *bridge;
3634 u16 cmd;
3635 int rc;
3636
3637 WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) & (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY)));
3638
3639 /* ARCH specific VGA enables */
3640 rc = pci_set_vga_state_arch(dev, decode, command_bits, flags);
3641 if (rc)
3642 return rc;
3643
3644 if (flags & PCI_VGA_STATE_CHANGE_DECODES) {
3645 pci_read_config_word(dev, PCI_COMMAND, &cmd);
3646 if (decode == true)
3647 cmd |= command_bits;
3648 else
3649 cmd &= ~command_bits;
3650 pci_write_config_word(dev, PCI_COMMAND, cmd);
3651 }
3652
3653 if (!(flags & PCI_VGA_STATE_CHANGE_BRIDGE))
3654 return 0;
3655
3656 bus = dev->bus;
3657 while (bus) {
3658 bridge = bus->self;
3659 if (bridge) {
3660 pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
3661 &cmd);
3662 if (decode == true)
3663 cmd |= PCI_BRIDGE_CTL_VGA;
3664 else
3665 cmd &= ~PCI_BRIDGE_CTL_VGA;
3666 pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
3667 cmd);
3668 }
3669 bus = bus->parent;
3670 }
3671 return 0;
3672 }
3673
3674 #define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
3675 static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
3676 static DEFINE_SPINLOCK(resource_alignment_lock);
3677
3678 /**
3679 * pci_specified_resource_alignment - get resource alignment specified by user.
3680 * @dev: the PCI device to get
3681 *
3682 * RETURNS: Resource alignment if it is specified.
3683 * Zero if it is not specified.
3684 */
3685 resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
3686 {
3687 int seg, bus, slot, func, align_order, count;
3688 resource_size_t align = 0;
3689 char *p;
3690
3691 spin_lock(&resource_alignment_lock);
3692 p = resource_alignment_param;
3693 while (*p) {
3694 count = 0;
3695 if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
3696 p[count] == '@') {
3697 p += count + 1;
3698 } else {
3699 align_order = -1;
3700 }
3701 if (sscanf(p, "%x:%x:%x.%x%n",
3702 &seg, &bus, &slot, &func, &count) != 4) {
3703 seg = 0;
3704 if (sscanf(p, "%x:%x.%x%n",
3705 &bus, &slot, &func, &count) != 3) {
3706 /* Invalid format */
3707 printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
3708 p);
3709 break;
3710 }
3711 }
3712 p += count;
3713 if (seg == pci_domain_nr(dev->bus) &&
3714 bus == dev->bus->number &&
3715 slot == PCI_SLOT(dev->devfn) &&
3716 func == PCI_FUNC(dev->devfn)) {
3717 if (align_order == -1) {
3718 align = PAGE_SIZE;
3719 } else {
3720 align = 1 << align_order;
3721 }
3722 /* Found */
3723 break;
3724 }
3725 if (*p != ';' && *p != ',') {
3726 /* End of param or invalid format */
3727 break;
3728 }
3729 p++;
3730 }
3731 spin_unlock(&resource_alignment_lock);
3732 return align;
3733 }
3734
3735 /**
3736 * pci_is_reassigndev - check if specified PCI is target device to reassign
3737 * @dev: the PCI device to check
3738 *
3739 * RETURNS: non-zero for PCI device is a target device to reassign,
3740 * or zero is not.
3741 */
3742 int pci_is_reassigndev(struct pci_dev *dev)
3743 {
3744 return (pci_specified_resource_alignment(dev) != 0);
3745 }
3746
3747 /*
3748 * This function disables memory decoding and releases memory resources
3749 * of the device specified by kernel's boot parameter 'pci=resource_alignment='.
3750 * It also rounds up size to specified alignment.
3751 * Later on, the kernel will assign page-aligned memory resource back
3752 * to the device.
3753 */
3754 void pci_reassigndev_resource_alignment(struct pci_dev *dev)
3755 {
3756 int i;
3757 struct resource *r;
3758 resource_size_t align, size;
3759 u16 command;
3760
3761 if (!pci_is_reassigndev(dev))
3762 return;
3763
3764 if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL &&
3765 (dev->class >> 8) == PCI_CLASS_BRIDGE_HOST) {
3766 dev_warn(&dev->dev,
3767 "Can't reassign resources to host bridge.\n");
3768 return;
3769 }
3770
3771 dev_info(&dev->dev,
3772 "Disabling memory decoding and releasing memory resources.\n");
3773 pci_read_config_word(dev, PCI_COMMAND, &command);
3774 command &= ~PCI_COMMAND_MEMORY;
3775 pci_write_config_word(dev, PCI_COMMAND, command);
3776
3777 align = pci_specified_resource_alignment(dev);
3778 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
3779 r = &dev->resource[i];
3780 if (!(r->flags & IORESOURCE_MEM))
3781 continue;
3782 size = resource_size(r);
3783 if (size < align) {
3784 size = align;
3785 dev_info(&dev->dev,
3786 "Rounding up size of resource #%d to %#llx.\n",
3787 i, (unsigned long long)size);
3788 }
3789 r->end = size - 1;
3790 r->start = 0;
3791 }
3792 /* Need to disable bridge's resource window,
3793 * to enable the kernel to reassign new resource
3794 * window later on.
3795 */
3796 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
3797 (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
3798 for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) {
3799 r = &dev->resource[i];
3800 if (!(r->flags & IORESOURCE_MEM))
3801 continue;
3802 r->end = resource_size(r) - 1;
3803 r->start = 0;
3804 }
3805 pci_disable_bridge_window(dev);
3806 }
3807 }
3808
3809 ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
3810 {
3811 if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
3812 count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
3813 spin_lock(&resource_alignment_lock);
3814 strncpy(resource_alignment_param, buf, count);
3815 resource_alignment_param[count] = '\0';
3816 spin_unlock(&resource_alignment_lock);
3817 return count;
3818 }
3819
3820 ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
3821 {
3822 size_t count;
3823 spin_lock(&resource_alignment_lock);
3824 count = snprintf(buf, size, "%s", resource_alignment_param);
3825 spin_unlock(&resource_alignment_lock);
3826 return count;
3827 }
3828
3829 static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
3830 {
3831 return pci_get_resource_alignment_param(buf, PAGE_SIZE);
3832 }
3833
3834 static ssize_t pci_resource_alignment_store(struct bus_type *bus,
3835 const char *buf, size_t count)
3836 {
3837 return pci_set_resource_alignment_param(buf, count);
3838 }
3839
3840 BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
3841 pci_resource_alignment_store);
3842
3843 static int __init pci_resource_alignment_sysfs_init(void)
3844 {
3845 return bus_create_file(&pci_bus_type,
3846 &bus_attr_resource_alignment);
3847 }
3848
3849 late_initcall(pci_resource_alignment_sysfs_init);
3850
3851 static void __devinit pci_no_domains(void)
3852 {
3853 #ifdef CONFIG_PCI_DOMAINS
3854 pci_domains_supported = 0;
3855 #endif
3856 }
3857
3858 /**
3859 * pci_ext_cfg_enabled - can we access extended PCI config space?
3860 * @dev: The PCI device of the root bridge.
3861 *
3862 * Returns 1 if we can access PCI extended config space (offsets
3863 * greater than 0xff). This is the default implementation. Architecture
3864 * implementations can override this.
3865 */
3866 int __attribute__ ((weak)) pci_ext_cfg_avail(struct pci_dev *dev)
3867 {
3868 return 1;
3869 }
3870
3871 void __weak pci_fixup_cardbus(struct pci_bus *bus)
3872 {
3873 }
3874 EXPORT_SYMBOL(pci_fixup_cardbus);
3875
3876 static int __init pci_setup(char *str)
3877 {
3878 while (str) {
3879 char *k = strchr(str, ',');
3880 if (k)
3881 *k++ = 0;
3882 if (*str && (str = pcibios_setup(str)) && *str) {
3883 if (!strcmp(str, "nomsi")) {
3884 pci_no_msi();
3885 } else if (!strcmp(str, "noaer")) {
3886 pci_no_aer();
3887 } else if (!strncmp(str, "realloc=", 8)) {
3888 pci_realloc_get_opt(str + 8);
3889 } else if (!strncmp(str, "realloc", 7)) {
3890 pci_realloc_get_opt("on");
3891 } else if (!strcmp(str, "nodomains")) {
3892 pci_no_domains();
3893 } else if (!strncmp(str, "noari", 5)) {
3894 pcie_ari_disabled = true;
3895 } else if (!strncmp(str, "cbiosize=", 9)) {
3896 pci_cardbus_io_size = memparse(str + 9, &str);
3897 } else if (!strncmp(str, "cbmemsize=", 10)) {
3898 pci_cardbus_mem_size = memparse(str + 10, &str);
3899 } else if (!strncmp(str, "resource_alignment=", 19)) {
3900 pci_set_resource_alignment_param(str + 19,
3901 strlen(str + 19));
3902 } else if (!strncmp(str, "ecrc=", 5)) {
3903 pcie_ecrc_get_policy(str + 5);
3904 } else if (!strncmp(str, "hpiosize=", 9)) {
3905 pci_hotplug_io_size = memparse(str + 9, &str);
3906 } else if (!strncmp(str, "hpmemsize=", 10)) {
3907 pci_hotplug_mem_size = memparse(str + 10, &str);
3908 } else if (!strncmp(str, "pcie_bus_tune_off", 17)) {
3909 pcie_bus_config = PCIE_BUS_TUNE_OFF;
3910 } else if (!strncmp(str, "pcie_bus_safe", 13)) {
3911 pcie_bus_config = PCIE_BUS_SAFE;
3912 } else if (!strncmp(str, "pcie_bus_perf", 13)) {
3913 pcie_bus_config = PCIE_BUS_PERFORMANCE;
3914 } else if (!strncmp(str, "pcie_bus_peer2peer", 18)) {
3915 pcie_bus_config = PCIE_BUS_PEER2PEER;
3916 } else if (!strncmp(str, "pcie_scan_all", 13)) {
3917 pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS);
3918 } else {
3919 printk(KERN_ERR "PCI: Unknown option `%s'\n",
3920 str);
3921 }
3922 }
3923 str = k;
3924 }
3925 return 0;
3926 }
3927 early_param("pci", pci_setup);
3928
3929 EXPORT_SYMBOL(pci_reenable_device);
3930 EXPORT_SYMBOL(pci_enable_device_io);
3931 EXPORT_SYMBOL(pci_enable_device_mem);
3932 EXPORT_SYMBOL(pci_enable_device);
3933 EXPORT_SYMBOL(pcim_enable_device);
3934 EXPORT_SYMBOL(pcim_pin_device);
3935 EXPORT_SYMBOL(pci_disable_device);
3936 EXPORT_SYMBOL(pci_find_capability);
3937 EXPORT_SYMBOL(pci_bus_find_capability);
3938 EXPORT_SYMBOL(pci_release_regions);
3939 EXPORT_SYMBOL(pci_request_regions);
3940 EXPORT_SYMBOL(pci_request_regions_exclusive);
3941 EXPORT_SYMBOL(pci_release_region);
3942 EXPORT_SYMBOL(pci_request_region);
3943 EXPORT_SYMBOL(pci_request_region_exclusive);
3944 EXPORT_SYMBOL(pci_release_selected_regions);
3945 EXPORT_SYMBOL(pci_request_selected_regions);
3946 EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
3947 EXPORT_SYMBOL(pci_set_master);
3948 EXPORT_SYMBOL(pci_clear_master);
3949 EXPORT_SYMBOL(pci_set_mwi);
3950 EXPORT_SYMBOL(pci_try_set_mwi);
3951 EXPORT_SYMBOL(pci_clear_mwi);
3952 EXPORT_SYMBOL_GPL(pci_intx);
3953 EXPORT_SYMBOL(pci_assign_resource);
3954 EXPORT_SYMBOL(pci_find_parent_resource);
3955 EXPORT_SYMBOL(pci_select_bars);
3956
3957 EXPORT_SYMBOL(pci_set_power_state);
3958 EXPORT_SYMBOL(pci_save_state);
3959 EXPORT_SYMBOL(pci_restore_state);
3960 EXPORT_SYMBOL(pci_pme_capable);
3961 EXPORT_SYMBOL(pci_pme_active);
3962 EXPORT_SYMBOL(pci_wake_from_d3);
3963 EXPORT_SYMBOL(pci_target_state);
3964 EXPORT_SYMBOL(pci_prepare_to_sleep);
3965 EXPORT_SYMBOL(pci_back_from_sleep);
3966 EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
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