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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/setup.h>
26#include "pci.h"
27
28const char *pci_power_names[] = {
29 "error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
30};
31EXPORT_SYMBOL_GPL(pci_power_names);
32
33int isa_dma_bridge_buggy;
34EXPORT_SYMBOL(isa_dma_bridge_buggy);
35
36int pci_pci_problems;
37EXPORT_SYMBOL(pci_pci_problems);
38
39unsigned int pci_pm_d3_delay;
40
41static void pci_pme_list_scan(struct work_struct *work);
42
43static LIST_HEAD(pci_pme_list);
44static DEFINE_MUTEX(pci_pme_list_mutex);
45static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan);
46
47struct pci_pme_device {
48 struct list_head list;
49 struct pci_dev *dev;
50};
51
52#define PME_TIMEOUT 1000 /* How long between PME checks */
53
54static void pci_dev_d3_sleep(struct pci_dev *dev)
55{
56 unsigned int delay = dev->d3_delay;
57
58 if (delay < pci_pm_d3_delay)
59 delay = pci_pm_d3_delay;
60
61 msleep(delay);
62}
63
64#ifdef CONFIG_PCI_DOMAINS
65int pci_domains_supported = 1;
66#endif
67
68#define DEFAULT_CARDBUS_IO_SIZE (256)
69#define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
70/* pci=cbmemsize=nnM,cbiosize=nn can override this */
71unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
72unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
73
74#define DEFAULT_HOTPLUG_IO_SIZE (256)
75#define DEFAULT_HOTPLUG_MEM_SIZE (2*1024*1024)
76/* pci=hpmemsize=nnM,hpiosize=nn can override this */
77unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE;
78unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
79
80enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_TUNE_OFF;
81
82/*
83 * The default CLS is used if arch didn't set CLS explicitly and not
84 * all pci devices agree on the same value. Arch can override either
85 * the dfl or actual value as it sees fit. Don't forget this is
86 * measured in 32-bit words, not bytes.
87 */
88u8 pci_dfl_cache_line_size __devinitdata = L1_CACHE_BYTES >> 2;
89u8 pci_cache_line_size;
90
91/**
92 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
93 * @bus: pointer to PCI bus structure to search
94 *
95 * Given a PCI bus, returns the highest PCI bus number present in the set
96 * including the given PCI bus and its list of child PCI buses.
97 */
98unsigned char pci_bus_max_busnr(struct pci_bus* bus)
99{
100 struct list_head *tmp;
101 unsigned char max, n;
102
103 max = bus->subordinate;
104 list_for_each(tmp, &bus->children) {
105 n = pci_bus_max_busnr(pci_bus_b(tmp));
106 if(n > max)
107 max = n;
108 }
109 return max;
110}
111EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
112
113#ifdef CONFIG_HAS_IOMEM
114void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
115{
116 /*
117 * Make sure the BAR is actually a memory resource, not an IO resource
118 */
119 if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
120 WARN_ON(1);
121 return NULL;
122 }
123 return ioremap_nocache(pci_resource_start(pdev, bar),
124 pci_resource_len(pdev, bar));
125}
126EXPORT_SYMBOL_GPL(pci_ioremap_bar);
127#endif
128
129#if 0
130/**
131 * pci_max_busnr - returns maximum PCI bus number
132 *
133 * Returns the highest PCI bus number present in the system global list of
134 * PCI buses.
135 */
136unsigned char __devinit
137pci_max_busnr(void)
138{
139 struct pci_bus *bus = NULL;
140 unsigned char max, n;
141
142 max = 0;
143 while ((bus = pci_find_next_bus(bus)) != NULL) {
144 n = pci_bus_max_busnr(bus);
145 if(n > max)
146 max = n;
147 }
148 return max;
149}
150
151#endif /* 0 */
152
153#define PCI_FIND_CAP_TTL 48
154
155static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
156 u8 pos, int cap, int *ttl)
157{
158 u8 id;
159
160 while ((*ttl)--) {
161 pci_bus_read_config_byte(bus, devfn, pos, &pos);
162 if (pos < 0x40)
163 break;
164 pos &= ~3;
165 pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
166 &id);
167 if (id == 0xff)
168 break;
169 if (id == cap)
170 return pos;
171 pos += PCI_CAP_LIST_NEXT;
172 }
173 return 0;
174}
175
176static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
177 u8 pos, int cap)
178{
179 int ttl = PCI_FIND_CAP_TTL;
180
181 return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
182}
183
184int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
185{
186 return __pci_find_next_cap(dev->bus, dev->devfn,
187 pos + PCI_CAP_LIST_NEXT, cap);
188}
189EXPORT_SYMBOL_GPL(pci_find_next_capability);
190
191static int __pci_bus_find_cap_start(struct pci_bus *bus,
192 unsigned int devfn, u8 hdr_type)
193{
194 u16 status;
195
196 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
197 if (!(status & PCI_STATUS_CAP_LIST))
198 return 0;
199
200 switch (hdr_type) {
201 case PCI_HEADER_TYPE_NORMAL:
202 case PCI_HEADER_TYPE_BRIDGE:
203 return PCI_CAPABILITY_LIST;
204 case PCI_HEADER_TYPE_CARDBUS:
205 return PCI_CB_CAPABILITY_LIST;
206 default:
207 return 0;
208 }
209
210 return 0;
211}
212
213/**
214 * pci_find_capability - query for devices' capabilities
215 * @dev: PCI device to query
216 * @cap: capability code
217 *
218 * Tell if a device supports a given PCI capability.
219 * Returns the address of the requested capability structure within the
220 * device's PCI configuration space or 0 in case the device does not
221 * support it. Possible values for @cap:
222 *
223 * %PCI_CAP_ID_PM Power Management
224 * %PCI_CAP_ID_AGP Accelerated Graphics Port
225 * %PCI_CAP_ID_VPD Vital Product Data
226 * %PCI_CAP_ID_SLOTID Slot Identification
227 * %PCI_CAP_ID_MSI Message Signalled Interrupts
228 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
229 * %PCI_CAP_ID_PCIX PCI-X
230 * %PCI_CAP_ID_EXP PCI Express
231 */
232int pci_find_capability(struct pci_dev *dev, int cap)
233{
234 int pos;
235
236 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
237 if (pos)
238 pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
239
240 return pos;
241}
242
243/**
244 * pci_bus_find_capability - query for devices' capabilities
245 * @bus: the PCI bus to query
246 * @devfn: PCI device to query
247 * @cap: capability code
248 *
249 * Like pci_find_capability() but works for pci devices that do not have a
250 * pci_dev structure set up yet.
251 *
252 * Returns the address of the requested capability structure within the
253 * device's PCI configuration space or 0 in case the device does not
254 * support it.
255 */
256int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
257{
258 int pos;
259 u8 hdr_type;
260
261 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
262
263 pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
264 if (pos)
265 pos = __pci_find_next_cap(bus, devfn, pos, cap);
266
267 return pos;
268}
269
270/**
271 * pci_find_ext_capability - Find an extended capability
272 * @dev: PCI device to query
273 * @cap: capability code
274 *
275 * Returns the address of the requested extended capability structure
276 * within the device's PCI configuration space or 0 if the device does
277 * not support it. Possible values for @cap:
278 *
279 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
280 * %PCI_EXT_CAP_ID_VC Virtual Channel
281 * %PCI_EXT_CAP_ID_DSN Device Serial Number
282 * %PCI_EXT_CAP_ID_PWR Power Budgeting
283 */
284int pci_find_ext_capability(struct pci_dev *dev, int cap)
285{
286 u32 header;
287 int ttl;
288 int pos = PCI_CFG_SPACE_SIZE;
289
290 /* minimum 8 bytes per capability */
291 ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
292
293 if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
294 return 0;
295
296 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
297 return 0;
298
299 /*
300 * If we have no capabilities, this is indicated by cap ID,
301 * cap version and next pointer all being 0.
302 */
303 if (header == 0)
304 return 0;
305
306 while (ttl-- > 0) {
307 if (PCI_EXT_CAP_ID(header) == cap)
308 return pos;
309
310 pos = PCI_EXT_CAP_NEXT(header);
311 if (pos < PCI_CFG_SPACE_SIZE)
312 break;
313
314 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
315 break;
316 }
317
318 return 0;
319}
320EXPORT_SYMBOL_GPL(pci_find_ext_capability);
321
322/**
323 * pci_bus_find_ext_capability - find an extended capability
324 * @bus: the PCI bus to query
325 * @devfn: PCI device to query
326 * @cap: capability code
327 *
328 * Like pci_find_ext_capability() but works for pci devices that do not have a
329 * pci_dev structure set up yet.
330 *
331 * Returns the address of the requested capability structure within the
332 * device's PCI configuration space or 0 in case the device does not
333 * support it.
334 */
335int pci_bus_find_ext_capability(struct pci_bus *bus, unsigned int devfn,
336 int cap)
337{
338 u32 header;
339 int ttl;
340 int pos = PCI_CFG_SPACE_SIZE;
341
342 /* minimum 8 bytes per capability */
343 ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
344
345 if (!pci_bus_read_config_dword(bus, devfn, pos, &header))
346 return 0;
347 if (header == 0xffffffff || header == 0)
348 return 0;
349
350 while (ttl-- > 0) {
351 if (PCI_EXT_CAP_ID(header) == cap)
352 return pos;
353
354 pos = PCI_EXT_CAP_NEXT(header);
355 if (pos < PCI_CFG_SPACE_SIZE)
356 break;
357
358 if (!pci_bus_read_config_dword(bus, devfn, pos, &header))
359 break;
360 }
361
362 return 0;
363}
364
365static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
366{
367 int rc, ttl = PCI_FIND_CAP_TTL;
368 u8 cap, mask;
369
370 if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
371 mask = HT_3BIT_CAP_MASK;
372 else
373 mask = HT_5BIT_CAP_MASK;
374
375 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
376 PCI_CAP_ID_HT, &ttl);
377 while (pos) {
378 rc = pci_read_config_byte(dev, pos + 3, &cap);
379 if (rc != PCIBIOS_SUCCESSFUL)
380 return 0;
381
382 if ((cap & mask) == ht_cap)
383 return pos;
384
385 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
386 pos + PCI_CAP_LIST_NEXT,
387 PCI_CAP_ID_HT, &ttl);
388 }
389
390 return 0;
391}
392/**
393 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
394 * @dev: PCI device to query
395 * @pos: Position from which to continue searching
396 * @ht_cap: Hypertransport capability code
397 *
398 * To be used in conjunction with pci_find_ht_capability() to search for
399 * all capabilities matching @ht_cap. @pos should always be a value returned
400 * from pci_find_ht_capability().
401 *
402 * NB. To be 100% safe against broken PCI devices, the caller should take
403 * steps to avoid an infinite loop.
404 */
405int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
406{
407 return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
408}
409EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
410
411/**
412 * pci_find_ht_capability - query a device's Hypertransport capabilities
413 * @dev: PCI device to query
414 * @ht_cap: Hypertransport capability code
415 *
416 * Tell if a device supports a given Hypertransport capability.
417 * Returns an address within the device's PCI configuration space
418 * or 0 in case the device does not support the request capability.
419 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
420 * which has a Hypertransport capability matching @ht_cap.
421 */
422int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
423{
424 int pos;
425
426 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
427 if (pos)
428 pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
429
430 return pos;
431}
432EXPORT_SYMBOL_GPL(pci_find_ht_capability);
433
434/**
435 * pci_find_parent_resource - return resource region of parent bus of given region
436 * @dev: PCI device structure contains resources to be searched
437 * @res: child resource record for which parent is sought
438 *
439 * For given resource region of given device, return the resource
440 * region of parent bus the given region is contained in or where
441 * it should be allocated from.
442 */
443struct resource *
444pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
445{
446 const struct pci_bus *bus = dev->bus;
447 int i;
448 struct resource *best = NULL, *r;
449
450 pci_bus_for_each_resource(bus, r, i) {
451 if (!r)
452 continue;
453 if (res->start && !(res->start >= r->start && res->end <= r->end))
454 continue; /* Not contained */
455 if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
456 continue; /* Wrong type */
457 if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
458 return r; /* Exact match */
459 /* We can't insert a non-prefetch resource inside a prefetchable parent .. */
460 if (r->flags & IORESOURCE_PREFETCH)
461 continue;
462 /* .. but we can put a prefetchable resource inside a non-prefetchable one */
463 if (!best)
464 best = r;
465 }
466 return best;
467}
468
469/**
470 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
471 * @dev: PCI device to have its BARs restored
472 *
473 * Restore the BAR values for a given device, so as to make it
474 * accessible by its driver.
475 */
476static void
477pci_restore_bars(struct pci_dev *dev)
478{
479 int i;
480
481 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
482 pci_update_resource(dev, i);
483}
484
485static struct pci_platform_pm_ops *pci_platform_pm;
486
487int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
488{
489 if (!ops->is_manageable || !ops->set_state || !ops->choose_state
490 || !ops->sleep_wake || !ops->can_wakeup)
491 return -EINVAL;
492 pci_platform_pm = ops;
493 return 0;
494}
495
496static inline bool platform_pci_power_manageable(struct pci_dev *dev)
497{
498 return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
499}
500
501static inline int platform_pci_set_power_state(struct pci_dev *dev,
502 pci_power_t t)
503{
504 return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
505}
506
507static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
508{
509 return pci_platform_pm ?
510 pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
511}
512
513static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
514{
515 return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
516}
517
518static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
519{
520 return pci_platform_pm ?
521 pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
522}
523
524static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable)
525{
526 return pci_platform_pm ?
527 pci_platform_pm->run_wake(dev, enable) : -ENODEV;
528}
529
530/**
531 * pci_raw_set_power_state - Use PCI PM registers to set the power state of
532 * given PCI device
533 * @dev: PCI device to handle.
534 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
535 *
536 * RETURN VALUE:
537 * -EINVAL if the requested state is invalid.
538 * -EIO if device does not support PCI PM or its PM capabilities register has a
539 * wrong version, or device doesn't support the requested state.
540 * 0 if device already is in the requested state.
541 * 0 if device's power state has been successfully changed.
542 */
543static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
544{
545 u16 pmcsr;
546 bool need_restore = false;
547
548 /* Check if we're already there */
549 if (dev->current_state == state)
550 return 0;
551
552 if (!dev->pm_cap)
553 return -EIO;
554
555 if (state < PCI_D0 || state > PCI_D3hot)
556 return -EINVAL;
557
558 /* Validate current state:
559 * Can enter D0 from any state, but if we can only go deeper
560 * to sleep if we're already in a low power state
561 */
562 if (state != PCI_D0 && dev->current_state <= PCI_D3cold
563 && dev->current_state > state) {
564 dev_err(&dev->dev, "invalid power transition "
565 "(from state %d to %d)\n", dev->current_state, state);
566 return -EINVAL;
567 }
568
569 /* check if this device supports the desired state */
570 if ((state == PCI_D1 && !dev->d1_support)
571 || (state == PCI_D2 && !dev->d2_support))
572 return -EIO;
573
574 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
575
576 /* If we're (effectively) in D3, force entire word to 0.
577 * This doesn't affect PME_Status, disables PME_En, and
578 * sets PowerState to 0.
579 */
580 switch (dev->current_state) {
581 case PCI_D0:
582 case PCI_D1:
583 case PCI_D2:
584 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
585 pmcsr |= state;
586 break;
587 case PCI_D3hot:
588 case PCI_D3cold:
589 case PCI_UNKNOWN: /* Boot-up */
590 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
591 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
592 need_restore = true;
593 /* Fall-through: force to D0 */
594 default:
595 pmcsr = 0;
596 break;
597 }
598
599 /* enter specified state */
600 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
601
602 /* Mandatory power management transition delays */
603 /* see PCI PM 1.1 5.6.1 table 18 */
604 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
605 pci_dev_d3_sleep(dev);
606 else if (state == PCI_D2 || dev->current_state == PCI_D2)
607 udelay(PCI_PM_D2_DELAY);
608
609 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
610 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
611 if (dev->current_state != state && printk_ratelimit())
612 dev_info(&dev->dev, "Refused to change power state, "
613 "currently in D%d\n", dev->current_state);
614
615 /* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
616 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
617 * from D3hot to D0 _may_ perform an internal reset, thereby
618 * going to "D0 Uninitialized" rather than "D0 Initialized".
619 * For example, at least some versions of the 3c905B and the
620 * 3c556B exhibit this behaviour.
621 *
622 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
623 * devices in a D3hot state at boot. Consequently, we need to
624 * restore at least the BARs so that the device will be
625 * accessible to its driver.
626 */
627 if (need_restore)
628 pci_restore_bars(dev);
629
630 if (dev->bus->self)
631 pcie_aspm_pm_state_change(dev->bus->self);
632
633 return 0;
634}
635
636/**
637 * pci_update_current_state - Read PCI power state of given device from its
638 * PCI PM registers and cache it
639 * @dev: PCI device to handle.
640 * @state: State to cache in case the device doesn't have the PM capability
641 */
642void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
643{
644 if (dev->pm_cap) {
645 u16 pmcsr;
646
647 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
648 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
649 } else {
650 dev->current_state = state;
651 }
652}
653
654/**
655 * pci_platform_power_transition - Use platform to change device power state
656 * @dev: PCI device to handle.
657 * @state: State to put the device into.
658 */
659static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
660{
661 int error;
662
663 if (platform_pci_power_manageable(dev)) {
664 error = platform_pci_set_power_state(dev, state);
665 if (!error)
666 pci_update_current_state(dev, state);
667 } else {
668 error = -ENODEV;
669 /* Fall back to PCI_D0 if native PM is not supported */
670 if (!dev->pm_cap)
671 dev->current_state = PCI_D0;
672 }
673
674 return error;
675}
676
677/**
678 * __pci_start_power_transition - Start power transition of a PCI device
679 * @dev: PCI device to handle.
680 * @state: State to put the device into.
681 */
682static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
683{
684 if (state == PCI_D0)
685 pci_platform_power_transition(dev, PCI_D0);
686}
687
688/**
689 * __pci_complete_power_transition - Complete power transition of a PCI device
690 * @dev: PCI device to handle.
691 * @state: State to put the device into.
692 *
693 * This function should not be called directly by device drivers.
694 */
695int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
696{
697 return state >= PCI_D0 ?
698 pci_platform_power_transition(dev, state) : -EINVAL;
699}
700EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
701
702/**
703 * pci_set_power_state - Set the power state of a PCI device
704 * @dev: PCI device to handle.
705 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
706 *
707 * Transition a device to a new power state, using the platform firmware and/or
708 * the device's PCI PM registers.
709 *
710 * RETURN VALUE:
711 * -EINVAL if the requested state is invalid.
712 * -EIO if device does not support PCI PM or its PM capabilities register has a
713 * wrong version, or device doesn't support the requested state.
714 * 0 if device already is in the requested state.
715 * 0 if device's power state has been successfully changed.
716 */
717int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
718{
719 int error;
720
721 /* bound the state we're entering */
722 if (state > PCI_D3hot)
723 state = PCI_D3hot;
724 else if (state < PCI_D0)
725 state = PCI_D0;
726 else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
727 /*
728 * If the device or the parent bridge do not support PCI PM,
729 * ignore the request if we're doing anything other than putting
730 * it into D0 (which would only happen on boot).
731 */
732 return 0;
733
734 __pci_start_power_transition(dev, state);
735
736 /* This device is quirked not to be put into D3, so
737 don't put it in D3 */
738 if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
739 return 0;
740
741 error = pci_raw_set_power_state(dev, state);
742
743 if (!__pci_complete_power_transition(dev, state))
744 error = 0;
745 /*
746 * When aspm_policy is "powersave" this call ensures
747 * that ASPM is configured.
748 */
749 if (!error && dev->bus->self)
750 pcie_aspm_powersave_config_link(dev->bus->self);
751
752 return error;
753}
754
755/**
756 * pci_choose_state - Choose the power state of a PCI device
757 * @dev: PCI device to be suspended
758 * @state: target sleep state for the whole system. This is the value
759 * that is passed to suspend() function.
760 *
761 * Returns PCI power state suitable for given device and given system
762 * message.
763 */
764
765pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
766{
767 pci_power_t ret;
768
769 if (!pci_find_capability(dev, PCI_CAP_ID_PM))
770 return PCI_D0;
771
772 ret = platform_pci_choose_state(dev);
773 if (ret != PCI_POWER_ERROR)
774 return ret;
775
776 switch (state.event) {
777 case PM_EVENT_ON:
778 return PCI_D0;
779 case PM_EVENT_FREEZE:
780 case PM_EVENT_PRETHAW:
781 /* REVISIT both freeze and pre-thaw "should" use D0 */
782 case PM_EVENT_SUSPEND:
783 case PM_EVENT_HIBERNATE:
784 return PCI_D3hot;
785 default:
786 dev_info(&dev->dev, "unrecognized suspend event %d\n",
787 state.event);
788 BUG();
789 }
790 return PCI_D0;
791}
792
793EXPORT_SYMBOL(pci_choose_state);
794
795#define PCI_EXP_SAVE_REGS 7
796
797#define pcie_cap_has_devctl(type, flags) 1
798#define pcie_cap_has_lnkctl(type, flags) \
799 ((flags & PCI_EXP_FLAGS_VERS) > 1 || \
800 (type == PCI_EXP_TYPE_ROOT_PORT || \
801 type == PCI_EXP_TYPE_ENDPOINT || \
802 type == PCI_EXP_TYPE_LEG_END))
803#define pcie_cap_has_sltctl(type, flags) \
804 ((flags & PCI_EXP_FLAGS_VERS) > 1 || \
805 ((type == PCI_EXP_TYPE_ROOT_PORT) || \
806 (type == PCI_EXP_TYPE_DOWNSTREAM && \
807 (flags & PCI_EXP_FLAGS_SLOT))))
808#define pcie_cap_has_rtctl(type, flags) \
809 ((flags & PCI_EXP_FLAGS_VERS) > 1 || \
810 (type == PCI_EXP_TYPE_ROOT_PORT || \
811 type == PCI_EXP_TYPE_RC_EC))
812#define pcie_cap_has_devctl2(type, flags) \
813 ((flags & PCI_EXP_FLAGS_VERS) > 1)
814#define pcie_cap_has_lnkctl2(type, flags) \
815 ((flags & PCI_EXP_FLAGS_VERS) > 1)
816#define pcie_cap_has_sltctl2(type, flags) \
817 ((flags & PCI_EXP_FLAGS_VERS) > 1)
818
819static int pci_save_pcie_state(struct pci_dev *dev)
820{
821 int pos, i = 0;
822 struct pci_cap_saved_state *save_state;
823 u16 *cap;
824 u16 flags;
825
826 pos = pci_pcie_cap(dev);
827 if (!pos)
828 return 0;
829
830 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
831 if (!save_state) {
832 dev_err(&dev->dev, "buffer not found in %s\n", __func__);
833 return -ENOMEM;
834 }
835 cap = (u16 *)&save_state->cap.data[0];
836
837 pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
838
839 if (pcie_cap_has_devctl(dev->pcie_type, flags))
840 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
841 if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
842 pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
843 if (pcie_cap_has_sltctl(dev->pcie_type, flags))
844 pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
845 if (pcie_cap_has_rtctl(dev->pcie_type, flags))
846 pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
847 if (pcie_cap_has_devctl2(dev->pcie_type, flags))
848 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &cap[i++]);
849 if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
850 pci_read_config_word(dev, pos + PCI_EXP_LNKCTL2, &cap[i++]);
851 if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
852 pci_read_config_word(dev, pos + PCI_EXP_SLTCTL2, &cap[i++]);
853
854 return 0;
855}
856
857static void pci_restore_pcie_state(struct pci_dev *dev)
858{
859 int i = 0, pos;
860 struct pci_cap_saved_state *save_state;
861 u16 *cap;
862 u16 flags;
863
864 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
865 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
866 if (!save_state || pos <= 0)
867 return;
868 cap = (u16 *)&save_state->cap.data[0];
869
870 pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
871
872 if (pcie_cap_has_devctl(dev->pcie_type, flags))
873 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
874 if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
875 pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
876 if (pcie_cap_has_sltctl(dev->pcie_type, flags))
877 pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
878 if (pcie_cap_has_rtctl(dev->pcie_type, flags))
879 pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
880 if (pcie_cap_has_devctl2(dev->pcie_type, flags))
881 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, cap[i++]);
882 if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
883 pci_write_config_word(dev, pos + PCI_EXP_LNKCTL2, cap[i++]);
884 if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
885 pci_write_config_word(dev, pos + PCI_EXP_SLTCTL2, cap[i++]);
886}
887
888
889static int pci_save_pcix_state(struct pci_dev *dev)
890{
891 int pos;
892 struct pci_cap_saved_state *save_state;
893
894 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
895 if (pos <= 0)
896 return 0;
897
898 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
899 if (!save_state) {
900 dev_err(&dev->dev, "buffer not found in %s\n", __func__);
901 return -ENOMEM;
902 }
903
904 pci_read_config_word(dev, pos + PCI_X_CMD,
905 (u16 *)save_state->cap.data);
906
907 return 0;
908}
909
910static void pci_restore_pcix_state(struct pci_dev *dev)
911{
912 int i = 0, pos;
913 struct pci_cap_saved_state *save_state;
914 u16 *cap;
915
916 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
917 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
918 if (!save_state || pos <= 0)
919 return;
920 cap = (u16 *)&save_state->cap.data[0];
921
922 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
923}
924
925
926/**
927 * pci_save_state - save the PCI configuration space of a device before suspending
928 * @dev: - PCI device that we're dealing with
929 */
930int
931pci_save_state(struct pci_dev *dev)
932{
933 int i;
934 /* XXX: 100% dword access ok here? */
935 for (i = 0; i < 16; i++)
936 pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
937 dev->state_saved = true;
938 if ((i = pci_save_pcie_state(dev)) != 0)
939 return i;
940 if ((i = pci_save_pcix_state(dev)) != 0)
941 return i;
942 return 0;
943}
944
945/**
946 * pci_restore_state - Restore the saved state of a PCI device
947 * @dev: - PCI device that we're dealing with
948 */
949void pci_restore_state(struct pci_dev *dev)
950{
951 int i;
952 u32 val;
953
954 if (!dev->state_saved)
955 return;
956
957 /* PCI Express register must be restored first */
958 pci_restore_pcie_state(dev);
959
960 /*
961 * The Base Address register should be programmed before the command
962 * register(s)
963 */
964 for (i = 15; i >= 0; i--) {
965 pci_read_config_dword(dev, i * 4, &val);
966 if (val != dev->saved_config_space[i]) {
967 dev_printk(KERN_DEBUG, &dev->dev, "restoring config "
968 "space at offset %#x (was %#x, writing %#x)\n",
969 i, val, (int)dev->saved_config_space[i]);
970 pci_write_config_dword(dev,i * 4,
971 dev->saved_config_space[i]);
972 }
973 }
974 pci_restore_pcix_state(dev);
975 pci_restore_msi_state(dev);
976 pci_restore_iov_state(dev);
977
978 dev->state_saved = false;
979}
980
981struct pci_saved_state {
982 u32 config_space[16];
983 struct pci_cap_saved_data cap[0];
984};
985
986/**
987 * pci_store_saved_state - Allocate and return an opaque struct containing
988 * the device saved state.
989 * @dev: PCI device that we're dealing with
990 *
991 * Rerturn NULL if no state or error.
992 */
993struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev)
994{
995 struct pci_saved_state *state;
996 struct pci_cap_saved_state *tmp;
997 struct pci_cap_saved_data *cap;
998 struct hlist_node *pos;
999 size_t size;
1000
1001 if (!dev->state_saved)
1002 return NULL;
1003
1004 size = sizeof(*state) + sizeof(struct pci_cap_saved_data);
1005
1006 hlist_for_each_entry(tmp, pos, &dev->saved_cap_space, next)
1007 size += sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1008
1009 state = kzalloc(size, GFP_KERNEL);
1010 if (!state)
1011 return NULL;
1012
1013 memcpy(state->config_space, dev->saved_config_space,
1014 sizeof(state->config_space));
1015
1016 cap = state->cap;
1017 hlist_for_each_entry(tmp, pos, &dev->saved_cap_space, next) {
1018 size_t len = sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1019 memcpy(cap, &tmp->cap, len);
1020 cap = (struct pci_cap_saved_data *)((u8 *)cap + len);
1021 }
1022 /* Empty cap_save terminates list */
1023
1024 return state;
1025}
1026EXPORT_SYMBOL_GPL(pci_store_saved_state);
1027
1028/**
1029 * pci_load_saved_state - Reload the provided save state into struct pci_dev.
1030 * @dev: PCI device that we're dealing with
1031 * @state: Saved state returned from pci_store_saved_state()
1032 */
1033int pci_load_saved_state(struct pci_dev *dev, struct pci_saved_state *state)
1034{
1035 struct pci_cap_saved_data *cap;
1036
1037 dev->state_saved = false;
1038
1039 if (!state)
1040 return 0;
1041
1042 memcpy(dev->saved_config_space, state->config_space,
1043 sizeof(state->config_space));
1044
1045 cap = state->cap;
1046 while (cap->size) {
1047 struct pci_cap_saved_state *tmp;
1048
1049 tmp = pci_find_saved_cap(dev, cap->cap_nr);
1050 if (!tmp || tmp->cap.size != cap->size)
1051 return -EINVAL;
1052
1053 memcpy(tmp->cap.data, cap->data, tmp->cap.size);
1054 cap = (struct pci_cap_saved_data *)((u8 *)cap +
1055 sizeof(struct pci_cap_saved_data) + cap->size);
1056 }
1057
1058 dev->state_saved = true;
1059 return 0;
1060}
1061EXPORT_SYMBOL_GPL(pci_load_saved_state);
1062
1063/**
1064 * pci_load_and_free_saved_state - Reload the save state pointed to by state,
1065 * and free the memory allocated for it.
1066 * @dev: PCI device that we're dealing with
1067 * @state: Pointer to saved state returned from pci_store_saved_state()
1068 */
1069int pci_load_and_free_saved_state(struct pci_dev *dev,
1070 struct pci_saved_state **state)
1071{
1072 int ret = pci_load_saved_state(dev, *state);
1073 kfree(*state);
1074 *state = NULL;
1075 return ret;
1076}
1077EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state);
1078
1079static int do_pci_enable_device(struct pci_dev *dev, int bars)
1080{
1081 int err;
1082
1083 err = pci_set_power_state(dev, PCI_D0);
1084 if (err < 0 && err != -EIO)
1085 return err;
1086 err = pcibios_enable_device(dev, bars);
1087 if (err < 0)
1088 return err;
1089 pci_fixup_device(pci_fixup_enable, dev);
1090
1091 return 0;
1092}
1093
1094/**
1095 * pci_reenable_device - Resume abandoned device
1096 * @dev: PCI device to be resumed
1097 *
1098 * Note this function is a backend of pci_default_resume and is not supposed
1099 * to be called by normal code, write proper resume handler and use it instead.
1100 */
1101int pci_reenable_device(struct pci_dev *dev)
1102{
1103 if (pci_is_enabled(dev))
1104 return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
1105 return 0;
1106}
1107
1108static int __pci_enable_device_flags(struct pci_dev *dev,
1109 resource_size_t flags)
1110{
1111 int err;
1112 int i, bars = 0;
1113
1114 /*
1115 * Power state could be unknown at this point, either due to a fresh
1116 * boot or a device removal call. So get the current power state
1117 * so that things like MSI message writing will behave as expected
1118 * (e.g. if the device really is in D0 at enable time).
1119 */
1120 if (dev->pm_cap) {
1121 u16 pmcsr;
1122 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1123 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
1124 }
1125
1126 if (atomic_add_return(1, &dev->enable_cnt) > 1)
1127 return 0; /* already enabled */
1128
1129 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1130 if (dev->resource[i].flags & flags)
1131 bars |= (1 << i);
1132
1133 err = do_pci_enable_device(dev, bars);
1134 if (err < 0)
1135 atomic_dec(&dev->enable_cnt);
1136 return err;
1137}
1138
1139/**
1140 * pci_enable_device_io - Initialize a device for use with IO space
1141 * @dev: PCI device to be initialized
1142 *
1143 * Initialize device before it's used by a driver. Ask low-level code
1144 * to enable I/O resources. Wake up the device if it was suspended.
1145 * Beware, this function can fail.
1146 */
1147int pci_enable_device_io(struct pci_dev *dev)
1148{
1149 return __pci_enable_device_flags(dev, IORESOURCE_IO);
1150}
1151
1152/**
1153 * pci_enable_device_mem - Initialize a device for use with Memory space
1154 * @dev: PCI device to be initialized
1155 *
1156 * Initialize device before it's used by a driver. Ask low-level code
1157 * to enable Memory resources. Wake up the device if it was suspended.
1158 * Beware, this function can fail.
1159 */
1160int pci_enable_device_mem(struct pci_dev *dev)
1161{
1162 return __pci_enable_device_flags(dev, IORESOURCE_MEM);
1163}
1164
1165/**
1166 * pci_enable_device - Initialize device before it's used by a driver.
1167 * @dev: PCI device to be initialized
1168 *
1169 * Initialize device before it's used by a driver. Ask low-level code
1170 * to enable I/O and memory. Wake up the device if it was suspended.
1171 * Beware, this function can fail.
1172 *
1173 * Note we don't actually enable the device many times if we call
1174 * this function repeatedly (we just increment the count).
1175 */
1176int pci_enable_device(struct pci_dev *dev)
1177{
1178 return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
1179}
1180
1181/*
1182 * Managed PCI resources. This manages device on/off, intx/msi/msix
1183 * on/off and BAR regions. pci_dev itself records msi/msix status, so
1184 * there's no need to track it separately. pci_devres is initialized
1185 * when a device is enabled using managed PCI device enable interface.
1186 */
1187struct pci_devres {
1188 unsigned int enabled:1;
1189 unsigned int pinned:1;
1190 unsigned int orig_intx:1;
1191 unsigned int restore_intx:1;
1192 u32 region_mask;
1193};
1194
1195static void pcim_release(struct device *gendev, void *res)
1196{
1197 struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
1198 struct pci_devres *this = res;
1199 int i;
1200
1201 if (dev->msi_enabled)
1202 pci_disable_msi(dev);
1203 if (dev->msix_enabled)
1204 pci_disable_msix(dev);
1205
1206 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1207 if (this->region_mask & (1 << i))
1208 pci_release_region(dev, i);
1209
1210 if (this->restore_intx)
1211 pci_intx(dev, this->orig_intx);
1212
1213 if (this->enabled && !this->pinned)
1214 pci_disable_device(dev);
1215}
1216
1217static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
1218{
1219 struct pci_devres *dr, *new_dr;
1220
1221 dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1222 if (dr)
1223 return dr;
1224
1225 new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1226 if (!new_dr)
1227 return NULL;
1228 return devres_get(&pdev->dev, new_dr, NULL, NULL);
1229}
1230
1231static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
1232{
1233 if (pci_is_managed(pdev))
1234 return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1235 return NULL;
1236}
1237
1238/**
1239 * pcim_enable_device - Managed pci_enable_device()
1240 * @pdev: PCI device to be initialized
1241 *
1242 * Managed pci_enable_device().
1243 */
1244int pcim_enable_device(struct pci_dev *pdev)
1245{
1246 struct pci_devres *dr;
1247 int rc;
1248
1249 dr = get_pci_dr(pdev);
1250 if (unlikely(!dr))
1251 return -ENOMEM;
1252 if (dr->enabled)
1253 return 0;
1254
1255 rc = pci_enable_device(pdev);
1256 if (!rc) {
1257 pdev->is_managed = 1;
1258 dr->enabled = 1;
1259 }
1260 return rc;
1261}
1262
1263/**
1264 * pcim_pin_device - Pin managed PCI device
1265 * @pdev: PCI device to pin
1266 *
1267 * Pin managed PCI device @pdev. Pinned device won't be disabled on
1268 * driver detach. @pdev must have been enabled with
1269 * pcim_enable_device().
1270 */
1271void pcim_pin_device(struct pci_dev *pdev)
1272{
1273 struct pci_devres *dr;
1274
1275 dr = find_pci_dr(pdev);
1276 WARN_ON(!dr || !dr->enabled);
1277 if (dr)
1278 dr->pinned = 1;
1279}
1280
1281/**
1282 * pcibios_disable_device - disable arch specific PCI resources for device dev
1283 * @dev: the PCI device to disable
1284 *
1285 * Disables architecture specific PCI resources for the device. This
1286 * is the default implementation. Architecture implementations can
1287 * override this.
1288 */
1289void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
1290
1291static void do_pci_disable_device(struct pci_dev *dev)
1292{
1293 u16 pci_command;
1294
1295 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1296 if (pci_command & PCI_COMMAND_MASTER) {
1297 pci_command &= ~PCI_COMMAND_MASTER;
1298 pci_write_config_word(dev, PCI_COMMAND, pci_command);
1299 }
1300
1301 pcibios_disable_device(dev);
1302}
1303
1304/**
1305 * pci_disable_enabled_device - Disable device without updating enable_cnt
1306 * @dev: PCI device to disable
1307 *
1308 * NOTE: This function is a backend of PCI power management routines and is
1309 * not supposed to be called drivers.
1310 */
1311void pci_disable_enabled_device(struct pci_dev *dev)
1312{
1313 if (pci_is_enabled(dev))
1314 do_pci_disable_device(dev);
1315}
1316
1317/**
1318 * pci_disable_device - Disable PCI device after use
1319 * @dev: PCI device to be disabled
1320 *
1321 * Signal to the system that the PCI device is not in use by the system
1322 * anymore. This only involves disabling PCI bus-mastering, if active.
1323 *
1324 * Note we don't actually disable the device until all callers of
1325 * pci_enable_device() have called pci_disable_device().
1326 */
1327void
1328pci_disable_device(struct pci_dev *dev)
1329{
1330 struct pci_devres *dr;
1331
1332 dr = find_pci_dr(dev);
1333 if (dr)
1334 dr->enabled = 0;
1335
1336 if (atomic_sub_return(1, &dev->enable_cnt) != 0)
1337 return;
1338
1339 do_pci_disable_device(dev);
1340
1341 dev->is_busmaster = 0;
1342}
1343
1344/**
1345 * pcibios_set_pcie_reset_state - set reset state for device dev
1346 * @dev: the PCIe device reset
1347 * @state: Reset state to enter into
1348 *
1349 *
1350 * Sets the PCIe reset state for the device. This is the default
1351 * implementation. Architecture implementations can override this.
1352 */
1353int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
1354 enum pcie_reset_state state)
1355{
1356 return -EINVAL;
1357}
1358
1359/**
1360 * pci_set_pcie_reset_state - set reset state for device dev
1361 * @dev: the PCIe device reset
1362 * @state: Reset state to enter into
1363 *
1364 *
1365 * Sets the PCI reset state for the device.
1366 */
1367int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1368{
1369 return pcibios_set_pcie_reset_state(dev, state);
1370}
1371
1372/**
1373 * pci_check_pme_status - Check if given device has generated PME.
1374 * @dev: Device to check.
1375 *
1376 * Check the PME status of the device and if set, clear it and clear PME enable
1377 * (if set). Return 'true' if PME status and PME enable were both set or
1378 * 'false' otherwise.
1379 */
1380bool pci_check_pme_status(struct pci_dev *dev)
1381{
1382 int pmcsr_pos;
1383 u16 pmcsr;
1384 bool ret = false;
1385
1386 if (!dev->pm_cap)
1387 return false;
1388
1389 pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
1390 pci_read_config_word(dev, pmcsr_pos, &pmcsr);
1391 if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
1392 return false;
1393
1394 /* Clear PME status. */
1395 pmcsr |= PCI_PM_CTRL_PME_STATUS;
1396 if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
1397 /* Disable PME to avoid interrupt flood. */
1398 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1399 ret = true;
1400 }
1401
1402 pci_write_config_word(dev, pmcsr_pos, pmcsr);
1403
1404 return ret;
1405}
1406
1407/**
1408 * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
1409 * @dev: Device to handle.
1410 * @ign: Ignored.
1411 *
1412 * Check if @dev has generated PME and queue a resume request for it in that
1413 * case.
1414 */
1415static int pci_pme_wakeup(struct pci_dev *dev, void *ign)
1416{
1417 if (pci_check_pme_status(dev)) {
1418 pci_wakeup_event(dev);
1419 pm_request_resume(&dev->dev);
1420 }
1421 return 0;
1422}
1423
1424/**
1425 * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
1426 * @bus: Top bus of the subtree to walk.
1427 */
1428void pci_pme_wakeup_bus(struct pci_bus *bus)
1429{
1430 if (bus)
1431 pci_walk_bus(bus, pci_pme_wakeup, NULL);
1432}
1433
1434/**
1435 * pci_pme_capable - check the capability of PCI device to generate PME#
1436 * @dev: PCI device to handle.
1437 * @state: PCI state from which device will issue PME#.
1438 */
1439bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1440{
1441 if (!dev->pm_cap)
1442 return false;
1443
1444 return !!(dev->pme_support & (1 << state));
1445}
1446
1447static void pci_pme_list_scan(struct work_struct *work)
1448{
1449 struct pci_pme_device *pme_dev;
1450
1451 mutex_lock(&pci_pme_list_mutex);
1452 if (!list_empty(&pci_pme_list)) {
1453 list_for_each_entry(pme_dev, &pci_pme_list, list)
1454 pci_pme_wakeup(pme_dev->dev, NULL);
1455 schedule_delayed_work(&pci_pme_work, msecs_to_jiffies(PME_TIMEOUT));
1456 }
1457 mutex_unlock(&pci_pme_list_mutex);
1458}
1459
1460/**
1461 * pci_external_pme - is a device an external PCI PME source?
1462 * @dev: PCI device to check
1463 *
1464 */
1465
1466static bool pci_external_pme(struct pci_dev *dev)
1467{
1468 if (pci_is_pcie(dev) || dev->bus->number == 0)
1469 return false;
1470 return true;
1471}
1472
1473/**
1474 * pci_pme_active - enable or disable PCI device's PME# function
1475 * @dev: PCI device to handle.
1476 * @enable: 'true' to enable PME# generation; 'false' to disable it.
1477 *
1478 * The caller must verify that the device is capable of generating PME# before
1479 * calling this function with @enable equal to 'true'.
1480 */
1481void pci_pme_active(struct pci_dev *dev, bool enable)
1482{
1483 u16 pmcsr;
1484
1485 if (!dev->pm_cap)
1486 return;
1487
1488 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1489 /* Clear PME_Status by writing 1 to it and enable PME# */
1490 pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1491 if (!enable)
1492 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1493
1494 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1495
1496 /* PCI (as opposed to PCIe) PME requires that the device have
1497 its PME# line hooked up correctly. Not all hardware vendors
1498 do this, so the PME never gets delivered and the device
1499 remains asleep. The easiest way around this is to
1500 periodically walk the list of suspended devices and check
1501 whether any have their PME flag set. The assumption is that
1502 we'll wake up often enough anyway that this won't be a huge
1503 hit, and the power savings from the devices will still be a
1504 win. */
1505
1506 if (pci_external_pme(dev)) {
1507 struct pci_pme_device *pme_dev;
1508 if (enable) {
1509 pme_dev = kmalloc(sizeof(struct pci_pme_device),
1510 GFP_KERNEL);
1511 if (!pme_dev)
1512 goto out;
1513 pme_dev->dev = dev;
1514 mutex_lock(&pci_pme_list_mutex);
1515 list_add(&pme_dev->list, &pci_pme_list);
1516 if (list_is_singular(&pci_pme_list))
1517 schedule_delayed_work(&pci_pme_work,
1518 msecs_to_jiffies(PME_TIMEOUT));
1519 mutex_unlock(&pci_pme_list_mutex);
1520 } else {
1521 mutex_lock(&pci_pme_list_mutex);
1522 list_for_each_entry(pme_dev, &pci_pme_list, list) {
1523 if (pme_dev->dev == dev) {
1524 list_del(&pme_dev->list);
1525 kfree(pme_dev);
1526 break;
1527 }
1528 }
1529 mutex_unlock(&pci_pme_list_mutex);
1530 }
1531 }
1532
1533out:
1534 dev_printk(KERN_DEBUG, &dev->dev, "PME# %s\n",
1535 enable ? "enabled" : "disabled");
1536}
1537
1538/**
1539 * __pci_enable_wake - enable PCI device as wakeup event source
1540 * @dev: PCI device affected
1541 * @state: PCI state from which device will issue wakeup events
1542 * @runtime: True if the events are to be generated at run time
1543 * @enable: True to enable event generation; false to disable
1544 *
1545 * This enables the device as a wakeup event source, or disables it.
1546 * When such events involves platform-specific hooks, those hooks are
1547 * called automatically by this routine.
1548 *
1549 * Devices with legacy power management (no standard PCI PM capabilities)
1550 * always require such platform hooks.
1551 *
1552 * RETURN VALUE:
1553 * 0 is returned on success
1554 * -EINVAL is returned if device is not supposed to wake up the system
1555 * Error code depending on the platform is returned if both the platform and
1556 * the native mechanism fail to enable the generation of wake-up events
1557 */
1558int __pci_enable_wake(struct pci_dev *dev, pci_power_t state,
1559 bool runtime, bool enable)
1560{
1561 int ret = 0;
1562
1563 if (enable && !runtime && !device_may_wakeup(&dev->dev))
1564 return -EINVAL;
1565
1566 /* Don't do the same thing twice in a row for one device. */
1567 if (!!enable == !!dev->wakeup_prepared)
1568 return 0;
1569
1570 /*
1571 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1572 * Anderson we should be doing PME# wake enable followed by ACPI wake
1573 * enable. To disable wake-up we call the platform first, for symmetry.
1574 */
1575
1576 if (enable) {
1577 int error;
1578
1579 if (pci_pme_capable(dev, state))
1580 pci_pme_active(dev, true);
1581 else
1582 ret = 1;
1583 error = runtime ? platform_pci_run_wake(dev, true) :
1584 platform_pci_sleep_wake(dev, true);
1585 if (ret)
1586 ret = error;
1587 if (!ret)
1588 dev->wakeup_prepared = true;
1589 } else {
1590 if (runtime)
1591 platform_pci_run_wake(dev, false);
1592 else
1593 platform_pci_sleep_wake(dev, false);
1594 pci_pme_active(dev, false);
1595 dev->wakeup_prepared = false;
1596 }
1597
1598 return ret;
1599}
1600EXPORT_SYMBOL(__pci_enable_wake);
1601
1602/**
1603 * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1604 * @dev: PCI device to prepare
1605 * @enable: True to enable wake-up event generation; false to disable
1606 *
1607 * Many drivers want the device to wake up the system from D3_hot or D3_cold
1608 * and this function allows them to set that up cleanly - pci_enable_wake()
1609 * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1610 * ordering constraints.
1611 *
1612 * This function only returns error code if the device is not capable of
1613 * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1614 * enable wake-up power for it.
1615 */
1616int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1617{
1618 return pci_pme_capable(dev, PCI_D3cold) ?
1619 pci_enable_wake(dev, PCI_D3cold, enable) :
1620 pci_enable_wake(dev, PCI_D3hot, enable);
1621}
1622
1623/**
1624 * pci_target_state - find an appropriate low power state for a given PCI dev
1625 * @dev: PCI device
1626 *
1627 * Use underlying platform code to find a supported low power state for @dev.
1628 * If the platform can't manage @dev, return the deepest state from which it
1629 * can generate wake events, based on any available PME info.
1630 */
1631pci_power_t pci_target_state(struct pci_dev *dev)
1632{
1633 pci_power_t target_state = PCI_D3hot;
1634
1635 if (platform_pci_power_manageable(dev)) {
1636 /*
1637 * Call the platform to choose the target state of the device
1638 * and enable wake-up from this state if supported.
1639 */
1640 pci_power_t state = platform_pci_choose_state(dev);
1641
1642 switch (state) {
1643 case PCI_POWER_ERROR:
1644 case PCI_UNKNOWN:
1645 break;
1646 case PCI_D1:
1647 case PCI_D2:
1648 if (pci_no_d1d2(dev))
1649 break;
1650 default:
1651 target_state = state;
1652 }
1653 } else if (!dev->pm_cap) {
1654 target_state = PCI_D0;
1655 } else if (device_may_wakeup(&dev->dev)) {
1656 /*
1657 * Find the deepest state from which the device can generate
1658 * wake-up events, make it the target state and enable device
1659 * to generate PME#.
1660 */
1661 if (dev->pme_support) {
1662 while (target_state
1663 && !(dev->pme_support & (1 << target_state)))
1664 target_state--;
1665 }
1666 }
1667
1668 return target_state;
1669}
1670
1671/**
1672 * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1673 * @dev: Device to handle.
1674 *
1675 * Choose the power state appropriate for the device depending on whether
1676 * it can wake up the system and/or is power manageable by the platform
1677 * (PCI_D3hot is the default) and put the device into that state.
1678 */
1679int pci_prepare_to_sleep(struct pci_dev *dev)
1680{
1681 pci_power_t target_state = pci_target_state(dev);
1682 int error;
1683
1684 if (target_state == PCI_POWER_ERROR)
1685 return -EIO;
1686
1687 pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
1688
1689 error = pci_set_power_state(dev, target_state);
1690
1691 if (error)
1692 pci_enable_wake(dev, target_state, false);
1693
1694 return error;
1695}
1696
1697/**
1698 * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1699 * @dev: Device to handle.
1700 *
1701 * Disable device's system wake-up capability and put it into D0.
1702 */
1703int pci_back_from_sleep(struct pci_dev *dev)
1704{
1705 pci_enable_wake(dev, PCI_D0, false);
1706 return pci_set_power_state(dev, PCI_D0);
1707}
1708
1709/**
1710 * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend.
1711 * @dev: PCI device being suspended.
1712 *
1713 * Prepare @dev to generate wake-up events at run time and put it into a low
1714 * power state.
1715 */
1716int pci_finish_runtime_suspend(struct pci_dev *dev)
1717{
1718 pci_power_t target_state = pci_target_state(dev);
1719 int error;
1720
1721 if (target_state == PCI_POWER_ERROR)
1722 return -EIO;
1723
1724 __pci_enable_wake(dev, target_state, true, pci_dev_run_wake(dev));
1725
1726 error = pci_set_power_state(dev, target_state);
1727
1728 if (error)
1729 __pci_enable_wake(dev, target_state, true, false);
1730
1731 return error;
1732}
1733
1734/**
1735 * pci_dev_run_wake - Check if device can generate run-time wake-up events.
1736 * @dev: Device to check.
1737 *
1738 * Return true if the device itself is cabable of generating wake-up events
1739 * (through the platform or using the native PCIe PME) or if the device supports
1740 * PME and one of its upstream bridges can generate wake-up events.
1741 */
1742bool pci_dev_run_wake(struct pci_dev *dev)
1743{
1744 struct pci_bus *bus = dev->bus;
1745
1746 if (device_run_wake(&dev->dev))
1747 return true;
1748
1749 if (!dev->pme_support)
1750 return false;
1751
1752 while (bus->parent) {
1753 struct pci_dev *bridge = bus->self;
1754
1755 if (device_run_wake(&bridge->dev))
1756 return true;
1757
1758 bus = bus->parent;
1759 }
1760
1761 /* We have reached the root bus. */
1762 if (bus->bridge)
1763 return device_run_wake(bus->bridge);
1764
1765 return false;
1766}
1767EXPORT_SYMBOL_GPL(pci_dev_run_wake);
1768
1769/**
1770 * pci_pm_init - Initialize PM functions of given PCI device
1771 * @dev: PCI device to handle.
1772 */
1773void pci_pm_init(struct pci_dev *dev)
1774{
1775 int pm;
1776 u16 pmc;
1777
1778 pm_runtime_forbid(&dev->dev);
1779 device_enable_async_suspend(&dev->dev);
1780 dev->wakeup_prepared = false;
1781
1782 dev->pm_cap = 0;
1783
1784 /* find PCI PM capability in list */
1785 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
1786 if (!pm)
1787 return;
1788 /* Check device's ability to generate PME# */
1789 pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
1790
1791 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
1792 dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
1793 pmc & PCI_PM_CAP_VER_MASK);
1794 return;
1795 }
1796
1797 dev->pm_cap = pm;
1798 dev->d3_delay = PCI_PM_D3_WAIT;
1799
1800 dev->d1_support = false;
1801 dev->d2_support = false;
1802 if (!pci_no_d1d2(dev)) {
1803 if (pmc & PCI_PM_CAP_D1)
1804 dev->d1_support = true;
1805 if (pmc & PCI_PM_CAP_D2)
1806 dev->d2_support = true;
1807
1808 if (dev->d1_support || dev->d2_support)
1809 dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
1810 dev->d1_support ? " D1" : "",
1811 dev->d2_support ? " D2" : "");
1812 }
1813
1814 pmc &= PCI_PM_CAP_PME_MASK;
1815 if (pmc) {
1816 dev_printk(KERN_DEBUG, &dev->dev,
1817 "PME# supported from%s%s%s%s%s\n",
1818 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
1819 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
1820 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
1821 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
1822 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
1823 dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
1824 /*
1825 * Make device's PM flags reflect the wake-up capability, but
1826 * let the user space enable it to wake up the system as needed.
1827 */
1828 device_set_wakeup_capable(&dev->dev, true);
1829 /* Disable the PME# generation functionality */
1830 pci_pme_active(dev, false);
1831 } else {
1832 dev->pme_support = 0;
1833 }
1834}
1835
1836/**
1837 * platform_pci_wakeup_init - init platform wakeup if present
1838 * @dev: PCI device
1839 *
1840 * Some devices don't have PCI PM caps but can still generate wakeup
1841 * events through platform methods (like ACPI events). If @dev supports
1842 * platform wakeup events, set the device flag to indicate as much. This
1843 * may be redundant if the device also supports PCI PM caps, but double
1844 * initialization should be safe in that case.
1845 */
1846void platform_pci_wakeup_init(struct pci_dev *dev)
1847{
1848 if (!platform_pci_can_wakeup(dev))
1849 return;
1850
1851 device_set_wakeup_capable(&dev->dev, true);
1852 platform_pci_sleep_wake(dev, false);
1853}
1854
1855/**
1856 * pci_add_save_buffer - allocate buffer for saving given capability registers
1857 * @dev: the PCI device
1858 * @cap: the capability to allocate the buffer for
1859 * @size: requested size of the buffer
1860 */
1861static int pci_add_cap_save_buffer(
1862 struct pci_dev *dev, char cap, unsigned int size)
1863{
1864 int pos;
1865 struct pci_cap_saved_state *save_state;
1866
1867 pos = pci_find_capability(dev, cap);
1868 if (pos <= 0)
1869 return 0;
1870
1871 save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
1872 if (!save_state)
1873 return -ENOMEM;
1874
1875 save_state->cap.cap_nr = cap;
1876 save_state->cap.size = size;
1877 pci_add_saved_cap(dev, save_state);
1878
1879 return 0;
1880}
1881
1882/**
1883 * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
1884 * @dev: the PCI device
1885 */
1886void pci_allocate_cap_save_buffers(struct pci_dev *dev)
1887{
1888 int error;
1889
1890 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
1891 PCI_EXP_SAVE_REGS * sizeof(u16));
1892 if (error)
1893 dev_err(&dev->dev,
1894 "unable to preallocate PCI Express save buffer\n");
1895
1896 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
1897 if (error)
1898 dev_err(&dev->dev,
1899 "unable to preallocate PCI-X save buffer\n");
1900}
1901
1902/**
1903 * pci_enable_ari - enable ARI forwarding if hardware support it
1904 * @dev: the PCI device
1905 */
1906void pci_enable_ari(struct pci_dev *dev)
1907{
1908 int pos;
1909 u32 cap;
1910 u16 flags, ctrl;
1911 struct pci_dev *bridge;
1912
1913 if (!pci_is_pcie(dev) || dev->devfn)
1914 return;
1915
1916 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1917 if (!pos)
1918 return;
1919
1920 bridge = dev->bus->self;
1921 if (!bridge || !pci_is_pcie(bridge))
1922 return;
1923
1924 pos = pci_pcie_cap(bridge);
1925 if (!pos)
1926 return;
1927
1928 /* ARI is a PCIe v2 feature */
1929 pci_read_config_word(bridge, pos + PCI_EXP_FLAGS, &flags);
1930 if ((flags & PCI_EXP_FLAGS_VERS) < 2)
1931 return;
1932
1933 pci_read_config_dword(bridge, pos + PCI_EXP_DEVCAP2, &cap);
1934 if (!(cap & PCI_EXP_DEVCAP2_ARI))
1935 return;
1936
1937 pci_read_config_word(bridge, pos + PCI_EXP_DEVCTL2, &ctrl);
1938 ctrl |= PCI_EXP_DEVCTL2_ARI;
1939 pci_write_config_word(bridge, pos + PCI_EXP_DEVCTL2, ctrl);
1940
1941 bridge->ari_enabled = 1;
1942}
1943
1944/**
1945 * pci_enable_ido - enable ID-based ordering on a device
1946 * @dev: the PCI device
1947 * @type: which types of IDO to enable
1948 *
1949 * Enable ID-based ordering on @dev. @type can contain the bits
1950 * %PCI_EXP_IDO_REQUEST and/or %PCI_EXP_IDO_COMPLETION to indicate
1951 * which types of transactions are allowed to be re-ordered.
1952 */
1953void pci_enable_ido(struct pci_dev *dev, unsigned long type)
1954{
1955 int pos;
1956 u16 ctrl;
1957
1958 pos = pci_pcie_cap(dev);
1959 if (!pos)
1960 return;
1961
1962 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
1963 if (type & PCI_EXP_IDO_REQUEST)
1964 ctrl |= PCI_EXP_IDO_REQ_EN;
1965 if (type & PCI_EXP_IDO_COMPLETION)
1966 ctrl |= PCI_EXP_IDO_CMP_EN;
1967 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
1968}
1969EXPORT_SYMBOL(pci_enable_ido);
1970
1971/**
1972 * pci_disable_ido - disable ID-based ordering on a device
1973 * @dev: the PCI device
1974 * @type: which types of IDO to disable
1975 */
1976void pci_disable_ido(struct pci_dev *dev, unsigned long type)
1977{
1978 int pos;
1979 u16 ctrl;
1980
1981 if (!pci_is_pcie(dev))
1982 return;
1983
1984 pos = pci_pcie_cap(dev);
1985 if (!pos)
1986 return;
1987
1988 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
1989 if (type & PCI_EXP_IDO_REQUEST)
1990 ctrl &= ~PCI_EXP_IDO_REQ_EN;
1991 if (type & PCI_EXP_IDO_COMPLETION)
1992 ctrl &= ~PCI_EXP_IDO_CMP_EN;
1993 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
1994}
1995EXPORT_SYMBOL(pci_disable_ido);
1996
1997/**
1998 * pci_enable_obff - enable optimized buffer flush/fill
1999 * @dev: PCI device
2000 * @type: type of signaling to use
2001 *
2002 * Try to enable @type OBFF signaling on @dev. It will try using WAKE#
2003 * signaling if possible, falling back to message signaling only if
2004 * WAKE# isn't supported. @type should indicate whether the PCIe link
2005 * be brought out of L0s or L1 to send the message. It should be either
2006 * %PCI_EXP_OBFF_SIGNAL_ALWAYS or %PCI_OBFF_SIGNAL_L0.
2007 *
2008 * If your device can benefit from receiving all messages, even at the
2009 * power cost of bringing the link back up from a low power state, use
2010 * %PCI_EXP_OBFF_SIGNAL_ALWAYS. Otherwise, use %PCI_OBFF_SIGNAL_L0 (the
2011 * preferred type).
2012 *
2013 * RETURNS:
2014 * Zero on success, appropriate error number on failure.
2015 */
2016int pci_enable_obff(struct pci_dev *dev, enum pci_obff_signal_type type)
2017{
2018 int pos;
2019 u32 cap;
2020 u16 ctrl;
2021 int ret;
2022
2023 if (!pci_is_pcie(dev))
2024 return -ENOTSUPP;
2025
2026 pos = pci_pcie_cap(dev);
2027 if (!pos)
2028 return -ENOTSUPP;
2029
2030 pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP2, &cap);
2031 if (!(cap & PCI_EXP_OBFF_MASK))
2032 return -ENOTSUPP; /* no OBFF support at all */
2033
2034 /* Make sure the topology supports OBFF as well */
2035 if (dev->bus) {
2036 ret = pci_enable_obff(dev->bus->self, type);
2037 if (ret)
2038 return ret;
2039 }
2040
2041 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
2042 if (cap & PCI_EXP_OBFF_WAKE)
2043 ctrl |= PCI_EXP_OBFF_WAKE_EN;
2044 else {
2045 switch (type) {
2046 case PCI_EXP_OBFF_SIGNAL_L0:
2047 if (!(ctrl & PCI_EXP_OBFF_WAKE_EN))
2048 ctrl |= PCI_EXP_OBFF_MSGA_EN;
2049 break;
2050 case PCI_EXP_OBFF_SIGNAL_ALWAYS:
2051 ctrl &= ~PCI_EXP_OBFF_WAKE_EN;
2052 ctrl |= PCI_EXP_OBFF_MSGB_EN;
2053 break;
2054 default:
2055 WARN(1, "bad OBFF signal type\n");
2056 return -ENOTSUPP;
2057 }
2058 }
2059 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
2060
2061 return 0;
2062}
2063EXPORT_SYMBOL(pci_enable_obff);
2064
2065/**
2066 * pci_disable_obff - disable optimized buffer flush/fill
2067 * @dev: PCI device
2068 *
2069 * Disable OBFF on @dev.
2070 */
2071void pci_disable_obff(struct pci_dev *dev)
2072{
2073 int pos;
2074 u16 ctrl;
2075
2076 if (!pci_is_pcie(dev))
2077 return;
2078
2079 pos = pci_pcie_cap(dev);
2080 if (!pos)
2081 return;
2082
2083 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
2084 ctrl &= ~PCI_EXP_OBFF_WAKE_EN;
2085 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
2086}
2087EXPORT_SYMBOL(pci_disable_obff);
2088
2089/**
2090 * pci_ltr_supported - check whether a device supports LTR
2091 * @dev: PCI device
2092 *
2093 * RETURNS:
2094 * True if @dev supports latency tolerance reporting, false otherwise.
2095 */
2096bool pci_ltr_supported(struct pci_dev *dev)
2097{
2098 int pos;
2099 u32 cap;
2100
2101 if (!pci_is_pcie(dev))
2102 return false;
2103
2104 pos = pci_pcie_cap(dev);
2105 if (!pos)
2106 return false;
2107
2108 pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP2, &cap);
2109
2110 return cap & PCI_EXP_DEVCAP2_LTR;
2111}
2112EXPORT_SYMBOL(pci_ltr_supported);
2113
2114/**
2115 * pci_enable_ltr - enable latency tolerance reporting
2116 * @dev: PCI device
2117 *
2118 * Enable LTR on @dev if possible, which means enabling it first on
2119 * upstream ports.
2120 *
2121 * RETURNS:
2122 * Zero on success, errno on failure.
2123 */
2124int pci_enable_ltr(struct pci_dev *dev)
2125{
2126 int pos;
2127 u16 ctrl;
2128 int ret;
2129
2130 if (!pci_ltr_supported(dev))
2131 return -ENOTSUPP;
2132
2133 pos = pci_pcie_cap(dev);
2134 if (!pos)
2135 return -ENOTSUPP;
2136
2137 /* Only primary function can enable/disable LTR */
2138 if (PCI_FUNC(dev->devfn) != 0)
2139 return -EINVAL;
2140
2141 /* Enable upstream ports first */
2142 if (dev->bus) {
2143 ret = pci_enable_ltr(dev->bus->self);
2144 if (ret)
2145 return ret;
2146 }
2147
2148 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
2149 ctrl |= PCI_EXP_LTR_EN;
2150 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
2151
2152 return 0;
2153}
2154EXPORT_SYMBOL(pci_enable_ltr);
2155
2156/**
2157 * pci_disable_ltr - disable latency tolerance reporting
2158 * @dev: PCI device
2159 */
2160void pci_disable_ltr(struct pci_dev *dev)
2161{
2162 int pos;
2163 u16 ctrl;
2164
2165 if (!pci_ltr_supported(dev))
2166 return;
2167
2168 pos = pci_pcie_cap(dev);
2169 if (!pos)
2170 return;
2171
2172 /* Only primary function can enable/disable LTR */
2173 if (PCI_FUNC(dev->devfn) != 0)
2174 return;
2175
2176 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl);
2177 ctrl &= ~PCI_EXP_LTR_EN;
2178 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl);
2179}
2180EXPORT_SYMBOL(pci_disable_ltr);
2181
2182static int __pci_ltr_scale(int *val)
2183{
2184 int scale = 0;
2185
2186 while (*val > 1023) {
2187 *val = (*val + 31) / 32;
2188 scale++;
2189 }
2190 return scale;
2191}
2192
2193/**
2194 * pci_set_ltr - set LTR latency values
2195 * @dev: PCI device
2196 * @snoop_lat_ns: snoop latency in nanoseconds
2197 * @nosnoop_lat_ns: nosnoop latency in nanoseconds
2198 *
2199 * Figure out the scale and set the LTR values accordingly.
2200 */
2201int pci_set_ltr(struct pci_dev *dev, int snoop_lat_ns, int nosnoop_lat_ns)
2202{
2203 int pos, ret, snoop_scale, nosnoop_scale;
2204 u16 val;
2205
2206 if (!pci_ltr_supported(dev))
2207 return -ENOTSUPP;
2208
2209 snoop_scale = __pci_ltr_scale(&snoop_lat_ns);
2210 nosnoop_scale = __pci_ltr_scale(&nosnoop_lat_ns);
2211
2212 if (snoop_lat_ns > PCI_LTR_VALUE_MASK ||
2213 nosnoop_lat_ns > PCI_LTR_VALUE_MASK)
2214 return -EINVAL;
2215
2216 if ((snoop_scale > (PCI_LTR_SCALE_MASK >> PCI_LTR_SCALE_SHIFT)) ||
2217 (nosnoop_scale > (PCI_LTR_SCALE_MASK >> PCI_LTR_SCALE_SHIFT)))
2218 return -EINVAL;
2219
2220 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_LTR);
2221 if (!pos)
2222 return -ENOTSUPP;
2223
2224 val = (snoop_scale << PCI_LTR_SCALE_SHIFT) | snoop_lat_ns;
2225 ret = pci_write_config_word(dev, pos + PCI_LTR_MAX_SNOOP_LAT, val);
2226 if (ret != 4)
2227 return -EIO;
2228
2229 val = (nosnoop_scale << PCI_LTR_SCALE_SHIFT) | nosnoop_lat_ns;
2230 ret = pci_write_config_word(dev, pos + PCI_LTR_MAX_NOSNOOP_LAT, val);
2231 if (ret != 4)
2232 return -EIO;
2233
2234 return 0;
2235}
2236EXPORT_SYMBOL(pci_set_ltr);
2237
2238static int pci_acs_enable;
2239
2240/**
2241 * pci_request_acs - ask for ACS to be enabled if supported
2242 */
2243void pci_request_acs(void)
2244{
2245 pci_acs_enable = 1;
2246}
2247
2248/**
2249 * pci_enable_acs - enable ACS if hardware support it
2250 * @dev: the PCI device
2251 */
2252void pci_enable_acs(struct pci_dev *dev)
2253{
2254 int pos;
2255 u16 cap;
2256 u16 ctrl;
2257
2258 if (!pci_acs_enable)
2259 return;
2260
2261 if (!pci_is_pcie(dev))
2262 return;
2263
2264 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
2265 if (!pos)
2266 return;
2267
2268 pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
2269 pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
2270
2271 /* Source Validation */
2272 ctrl |= (cap & PCI_ACS_SV);
2273
2274 /* P2P Request Redirect */
2275 ctrl |= (cap & PCI_ACS_RR);
2276
2277 /* P2P Completion Redirect */
2278 ctrl |= (cap & PCI_ACS_CR);
2279
2280 /* Upstream Forwarding */
2281 ctrl |= (cap & PCI_ACS_UF);
2282
2283 pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
2284}
2285
2286/**
2287 * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
2288 * @dev: the PCI device
2289 * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTD, 4=INTD)
2290 *
2291 * Perform INTx swizzling for a device behind one level of bridge. This is
2292 * required by section 9.1 of the PCI-to-PCI bridge specification for devices
2293 * behind bridges on add-in cards. For devices with ARI enabled, the slot
2294 * number is always 0 (see the Implementation Note in section 2.2.8.1 of
2295 * the PCI Express Base Specification, Revision 2.1)
2296 */
2297u8 pci_swizzle_interrupt_pin(struct pci_dev *dev, u8 pin)
2298{
2299 int slot;
2300
2301 if (pci_ari_enabled(dev->bus))
2302 slot = 0;
2303 else
2304 slot = PCI_SLOT(dev->devfn);
2305
2306 return (((pin - 1) + slot) % 4) + 1;
2307}
2308
2309int
2310pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
2311{
2312 u8 pin;
2313
2314 pin = dev->pin;
2315 if (!pin)
2316 return -1;
2317
2318 while (!pci_is_root_bus(dev->bus)) {
2319 pin = pci_swizzle_interrupt_pin(dev, pin);
2320 dev = dev->bus->self;
2321 }
2322 *bridge = dev;
2323 return pin;
2324}
2325
2326/**
2327 * pci_common_swizzle - swizzle INTx all the way to root bridge
2328 * @dev: the PCI device
2329 * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
2330 *
2331 * Perform INTx swizzling for a device. This traverses through all PCI-to-PCI
2332 * bridges all the way up to a PCI root bus.
2333 */
2334u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
2335{
2336 u8 pin = *pinp;
2337
2338 while (!pci_is_root_bus(dev->bus)) {
2339 pin = pci_swizzle_interrupt_pin(dev, pin);
2340 dev = dev->bus->self;
2341 }
2342 *pinp = pin;
2343 return PCI_SLOT(dev->devfn);
2344}
2345
2346/**
2347 * pci_release_region - Release a PCI bar
2348 * @pdev: PCI device whose resources were previously reserved by pci_request_region
2349 * @bar: BAR to release
2350 *
2351 * Releases the PCI I/O and memory resources previously reserved by a
2352 * successful call to pci_request_region. Call this function only
2353 * after all use of the PCI regions has ceased.
2354 */
2355void pci_release_region(struct pci_dev *pdev, int bar)
2356{
2357 struct pci_devres *dr;
2358
2359 if (pci_resource_len(pdev, bar) == 0)
2360 return;
2361 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
2362 release_region(pci_resource_start(pdev, bar),
2363 pci_resource_len(pdev, bar));
2364 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
2365 release_mem_region(pci_resource_start(pdev, bar),
2366 pci_resource_len(pdev, bar));
2367
2368 dr = find_pci_dr(pdev);
2369 if (dr)
2370 dr->region_mask &= ~(1 << bar);
2371}
2372
2373/**
2374 * __pci_request_region - Reserved PCI I/O and memory resource
2375 * @pdev: PCI device whose resources are to be reserved
2376 * @bar: BAR to be reserved
2377 * @res_name: Name to be associated with resource.
2378 * @exclusive: whether the region access is exclusive or not
2379 *
2380 * Mark the PCI region associated with PCI device @pdev BR @bar as
2381 * being reserved by owner @res_name. Do not access any
2382 * address inside the PCI regions unless this call returns
2383 * successfully.
2384 *
2385 * If @exclusive is set, then the region is marked so that userspace
2386 * is explicitly not allowed to map the resource via /dev/mem or
2387 * sysfs MMIO access.
2388 *
2389 * Returns 0 on success, or %EBUSY on error. A warning
2390 * message is also printed on failure.
2391 */
2392static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
2393 int exclusive)
2394{
2395 struct pci_devres *dr;
2396
2397 if (pci_resource_len(pdev, bar) == 0)
2398 return 0;
2399
2400 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
2401 if (!request_region(pci_resource_start(pdev, bar),
2402 pci_resource_len(pdev, bar), res_name))
2403 goto err_out;
2404 }
2405 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
2406 if (!__request_mem_region(pci_resource_start(pdev, bar),
2407 pci_resource_len(pdev, bar), res_name,
2408 exclusive))
2409 goto err_out;
2410 }
2411
2412 dr = find_pci_dr(pdev);
2413 if (dr)
2414 dr->region_mask |= 1 << bar;
2415
2416 return 0;
2417
2418err_out:
2419 dev_warn(&pdev->dev, "BAR %d: can't reserve %pR\n", bar,
2420 &pdev->resource[bar]);
2421 return -EBUSY;
2422}
2423
2424/**
2425 * pci_request_region - Reserve PCI I/O and memory resource
2426 * @pdev: PCI device whose resources are to be reserved
2427 * @bar: BAR to be reserved
2428 * @res_name: Name to be associated with resource
2429 *
2430 * Mark the PCI region associated with PCI device @pdev BAR @bar as
2431 * being reserved by owner @res_name. Do not access any
2432 * address inside the PCI regions unless this call returns
2433 * successfully.
2434 *
2435 * Returns 0 on success, or %EBUSY on error. A warning
2436 * message is also printed on failure.
2437 */
2438int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
2439{
2440 return __pci_request_region(pdev, bar, res_name, 0);
2441}
2442
2443/**
2444 * pci_request_region_exclusive - Reserved PCI I/O and memory resource
2445 * @pdev: PCI device whose resources are to be reserved
2446 * @bar: BAR to be reserved
2447 * @res_name: Name to be associated with resource.
2448 *
2449 * Mark the PCI region associated with PCI device @pdev BR @bar as
2450 * being reserved by owner @res_name. Do not access any
2451 * address inside the PCI regions unless this call returns
2452 * successfully.
2453 *
2454 * Returns 0 on success, or %EBUSY on error. A warning
2455 * message is also printed on failure.
2456 *
2457 * The key difference that _exclusive makes it that userspace is
2458 * explicitly not allowed to map the resource via /dev/mem or
2459 * sysfs.
2460 */
2461int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name)
2462{
2463 return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
2464}
2465/**
2466 * pci_release_selected_regions - Release selected PCI I/O and memory resources
2467 * @pdev: PCI device whose resources were previously reserved
2468 * @bars: Bitmask of BARs to be released
2469 *
2470 * Release selected PCI I/O and memory resources previously reserved.
2471 * Call this function only after all use of the PCI regions has ceased.
2472 */
2473void pci_release_selected_regions(struct pci_dev *pdev, int bars)
2474{
2475 int i;
2476
2477 for (i = 0; i < 6; i++)
2478 if (bars & (1 << i))
2479 pci_release_region(pdev, i);
2480}
2481
2482int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
2483 const char *res_name, int excl)
2484{
2485 int i;
2486
2487 for (i = 0; i < 6; i++)
2488 if (bars & (1 << i))
2489 if (__pci_request_region(pdev, i, res_name, excl))
2490 goto err_out;
2491 return 0;
2492
2493err_out:
2494 while(--i >= 0)
2495 if (bars & (1 << i))
2496 pci_release_region(pdev, i);
2497
2498 return -EBUSY;
2499}
2500
2501
2502/**
2503 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
2504 * @pdev: PCI device whose resources are to be reserved
2505 * @bars: Bitmask of BARs to be requested
2506 * @res_name: Name to be associated with resource
2507 */
2508int pci_request_selected_regions(struct pci_dev *pdev, int bars,
2509 const char *res_name)
2510{
2511 return __pci_request_selected_regions(pdev, bars, res_name, 0);
2512}
2513
2514int pci_request_selected_regions_exclusive(struct pci_dev *pdev,
2515 int bars, const char *res_name)
2516{
2517 return __pci_request_selected_regions(pdev, bars, res_name,
2518 IORESOURCE_EXCLUSIVE);
2519}
2520
2521/**
2522 * pci_release_regions - Release reserved PCI I/O and memory resources
2523 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
2524 *
2525 * Releases all PCI I/O and memory resources previously reserved by a
2526 * successful call to pci_request_regions. Call this function only
2527 * after all use of the PCI regions has ceased.
2528 */
2529
2530void pci_release_regions(struct pci_dev *pdev)
2531{
2532 pci_release_selected_regions(pdev, (1 << 6) - 1);
2533}
2534
2535/**
2536 * pci_request_regions - Reserved PCI I/O and memory resources
2537 * @pdev: PCI device whose resources are to be reserved
2538 * @res_name: Name to be associated with resource.
2539 *
2540 * Mark all PCI regions associated with PCI device @pdev as
2541 * being reserved by owner @res_name. Do not access any
2542 * address inside the PCI regions unless this call returns
2543 * successfully.
2544 *
2545 * Returns 0 on success, or %EBUSY on error. A warning
2546 * message is also printed on failure.
2547 */
2548int pci_request_regions(struct pci_dev *pdev, const char *res_name)
2549{
2550 return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
2551}
2552
2553/**
2554 * pci_request_regions_exclusive - Reserved PCI I/O and memory resources
2555 * @pdev: PCI device whose resources are to be reserved
2556 * @res_name: Name to be associated with resource.
2557 *
2558 * Mark all PCI regions associated with PCI device @pdev as
2559 * being reserved by owner @res_name. Do not access any
2560 * address inside the PCI regions unless this call returns
2561 * successfully.
2562 *
2563 * pci_request_regions_exclusive() will mark the region so that
2564 * /dev/mem and the sysfs MMIO access will not be allowed.
2565 *
2566 * Returns 0 on success, or %EBUSY on error. A warning
2567 * message is also printed on failure.
2568 */
2569int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
2570{
2571 return pci_request_selected_regions_exclusive(pdev,
2572 ((1 << 6) - 1), res_name);
2573}
2574
2575static void __pci_set_master(struct pci_dev *dev, bool enable)
2576{
2577 u16 old_cmd, cmd;
2578
2579 pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
2580 if (enable)
2581 cmd = old_cmd | PCI_COMMAND_MASTER;
2582 else
2583 cmd = old_cmd & ~PCI_COMMAND_MASTER;
2584 if (cmd != old_cmd) {
2585 dev_dbg(&dev->dev, "%s bus mastering\n",
2586 enable ? "enabling" : "disabling");
2587 pci_write_config_word(dev, PCI_COMMAND, cmd);
2588 }
2589 dev->is_busmaster = enable;
2590}
2591
2592/**
2593 * pci_set_master - enables bus-mastering for device dev
2594 * @dev: the PCI device to enable
2595 *
2596 * Enables bus-mastering on the device and calls pcibios_set_master()
2597 * to do the needed arch specific settings.
2598 */
2599void pci_set_master(struct pci_dev *dev)
2600{
2601 __pci_set_master(dev, true);
2602 pcibios_set_master(dev);
2603}
2604
2605/**
2606 * pci_clear_master - disables bus-mastering for device dev
2607 * @dev: the PCI device to disable
2608 */
2609void pci_clear_master(struct pci_dev *dev)
2610{
2611 __pci_set_master(dev, false);
2612}
2613
2614/**
2615 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
2616 * @dev: the PCI device for which MWI is to be enabled
2617 *
2618 * Helper function for pci_set_mwi.
2619 * Originally copied from drivers/net/acenic.c.
2620 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
2621 *
2622 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2623 */
2624int pci_set_cacheline_size(struct pci_dev *dev)
2625{
2626 u8 cacheline_size;
2627
2628 if (!pci_cache_line_size)
2629 return -EINVAL;
2630
2631 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
2632 equal to or multiple of the right value. */
2633 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2634 if (cacheline_size >= pci_cache_line_size &&
2635 (cacheline_size % pci_cache_line_size) == 0)
2636 return 0;
2637
2638 /* Write the correct value. */
2639 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
2640 /* Read it back. */
2641 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2642 if (cacheline_size == pci_cache_line_size)
2643 return 0;
2644
2645 dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
2646 "supported\n", pci_cache_line_size << 2);
2647
2648 return -EINVAL;
2649}
2650EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
2651
2652#ifdef PCI_DISABLE_MWI
2653int pci_set_mwi(struct pci_dev *dev)
2654{
2655 return 0;
2656}
2657
2658int pci_try_set_mwi(struct pci_dev *dev)
2659{
2660 return 0;
2661}
2662
2663void pci_clear_mwi(struct pci_dev *dev)
2664{
2665}
2666
2667#else
2668
2669/**
2670 * pci_set_mwi - enables memory-write-invalidate PCI transaction
2671 * @dev: the PCI device for which MWI is enabled
2672 *
2673 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2674 *
2675 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2676 */
2677int
2678pci_set_mwi(struct pci_dev *dev)
2679{
2680 int rc;
2681 u16 cmd;
2682
2683 rc = pci_set_cacheline_size(dev);
2684 if (rc)
2685 return rc;
2686
2687 pci_read_config_word(dev, PCI_COMMAND, &cmd);
2688 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
2689 dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
2690 cmd |= PCI_COMMAND_INVALIDATE;
2691 pci_write_config_word(dev, PCI_COMMAND, cmd);
2692 }
2693
2694 return 0;
2695}
2696
2697/**
2698 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
2699 * @dev: the PCI device for which MWI is enabled
2700 *
2701 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2702 * Callers are not required to check the return value.
2703 *
2704 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2705 */
2706int pci_try_set_mwi(struct pci_dev *dev)
2707{
2708 int rc = pci_set_mwi(dev);
2709 return rc;
2710}
2711
2712/**
2713 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
2714 * @dev: the PCI device to disable
2715 *
2716 * Disables PCI Memory-Write-Invalidate transaction on the device
2717 */
2718void
2719pci_clear_mwi(struct pci_dev *dev)
2720{
2721 u16 cmd;
2722
2723 pci_read_config_word(dev, PCI_COMMAND, &cmd);
2724 if (cmd & PCI_COMMAND_INVALIDATE) {
2725 cmd &= ~PCI_COMMAND_INVALIDATE;
2726 pci_write_config_word(dev, PCI_COMMAND, cmd);
2727 }
2728}
2729#endif /* ! PCI_DISABLE_MWI */
2730
2731/**
2732 * pci_intx - enables/disables PCI INTx for device dev
2733 * @pdev: the PCI device to operate on
2734 * @enable: boolean: whether to enable or disable PCI INTx
2735 *
2736 * Enables/disables PCI INTx for device dev
2737 */
2738void
2739pci_intx(struct pci_dev *pdev, int enable)
2740{
2741 u16 pci_command, new;
2742
2743 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
2744
2745 if (enable) {
2746 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
2747 } else {
2748 new = pci_command | PCI_COMMAND_INTX_DISABLE;
2749 }
2750
2751 if (new != pci_command) {
2752 struct pci_devres *dr;
2753
2754 pci_write_config_word(pdev, PCI_COMMAND, new);
2755
2756 dr = find_pci_dr(pdev);
2757 if (dr && !dr->restore_intx) {
2758 dr->restore_intx = 1;
2759 dr->orig_intx = !enable;
2760 }
2761 }
2762}
2763
2764/**
2765 * pci_msi_off - disables any msi or msix capabilities
2766 * @dev: the PCI device to operate on
2767 *
2768 * If you want to use msi see pci_enable_msi and friends.
2769 * This is a lower level primitive that allows us to disable
2770 * msi operation at the device level.
2771 */
2772void pci_msi_off(struct pci_dev *dev)
2773{
2774 int pos;
2775 u16 control;
2776
2777 pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
2778 if (pos) {
2779 pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
2780 control &= ~PCI_MSI_FLAGS_ENABLE;
2781 pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
2782 }
2783 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
2784 if (pos) {
2785 pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
2786 control &= ~PCI_MSIX_FLAGS_ENABLE;
2787 pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
2788 }
2789}
2790EXPORT_SYMBOL_GPL(pci_msi_off);
2791
2792int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
2793{
2794 return dma_set_max_seg_size(&dev->dev, size);
2795}
2796EXPORT_SYMBOL(pci_set_dma_max_seg_size);
2797
2798int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
2799{
2800 return dma_set_seg_boundary(&dev->dev, mask);
2801}
2802EXPORT_SYMBOL(pci_set_dma_seg_boundary);
2803
2804static int pcie_flr(struct pci_dev *dev, int probe)
2805{
2806 int i;
2807 int pos;
2808 u32 cap;
2809 u16 status, control;
2810
2811 pos = pci_pcie_cap(dev);
2812 if (!pos)
2813 return -ENOTTY;
2814
2815 pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP, &cap);
2816 if (!(cap & PCI_EXP_DEVCAP_FLR))
2817 return -ENOTTY;
2818
2819 if (probe)
2820 return 0;
2821
2822 /* Wait for Transaction Pending bit clean */
2823 for (i = 0; i < 4; i++) {
2824 if (i)
2825 msleep((1 << (i - 1)) * 100);
2826
2827 pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &status);
2828 if (!(status & PCI_EXP_DEVSTA_TRPND))
2829 goto clear;
2830 }
2831
2832 dev_err(&dev->dev, "transaction is not cleared; "
2833 "proceeding with reset anyway\n");
2834
2835clear:
2836 pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &control);
2837 control |= PCI_EXP_DEVCTL_BCR_FLR;
2838 pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, control);
2839
2840 msleep(100);
2841
2842 return 0;
2843}
2844
2845static int pci_af_flr(struct pci_dev *dev, int probe)
2846{
2847 int i;
2848 int pos;
2849 u8 cap;
2850 u8 status;
2851
2852 pos = pci_find_capability(dev, PCI_CAP_ID_AF);
2853 if (!pos)
2854 return -ENOTTY;
2855
2856 pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
2857 if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
2858 return -ENOTTY;
2859
2860 if (probe)
2861 return 0;
2862
2863 /* Wait for Transaction Pending bit clean */
2864 for (i = 0; i < 4; i++) {
2865 if (i)
2866 msleep((1 << (i - 1)) * 100);
2867
2868 pci_read_config_byte(dev, pos + PCI_AF_STATUS, &status);
2869 if (!(status & PCI_AF_STATUS_TP))
2870 goto clear;
2871 }
2872
2873 dev_err(&dev->dev, "transaction is not cleared; "
2874 "proceeding with reset anyway\n");
2875
2876clear:
2877 pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
2878 msleep(100);
2879
2880 return 0;
2881}
2882
2883/**
2884 * pci_pm_reset - Put device into PCI_D3 and back into PCI_D0.
2885 * @dev: Device to reset.
2886 * @probe: If set, only check if the device can be reset this way.
2887 *
2888 * If @dev supports native PCI PM and its PCI_PM_CTRL_NO_SOFT_RESET flag is
2889 * unset, it will be reinitialized internally when going from PCI_D3hot to
2890 * PCI_D0. If that's the case and the device is not in a low-power state
2891 * already, force it into PCI_D3hot and back to PCI_D0, causing it to be reset.
2892 *
2893 * NOTE: This causes the caller to sleep for twice the device power transition
2894 * cooldown period, which for the D0->D3hot and D3hot->D0 transitions is 10 ms
2895 * by devault (i.e. unless the @dev's d3_delay field has a different value).
2896 * Moreover, only devices in D0 can be reset by this function.
2897 */
2898static int pci_pm_reset(struct pci_dev *dev, int probe)
2899{
2900 u16 csr;
2901
2902 if (!dev->pm_cap)
2903 return -ENOTTY;
2904
2905 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
2906 if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
2907 return -ENOTTY;
2908
2909 if (probe)
2910 return 0;
2911
2912 if (dev->current_state != PCI_D0)
2913 return -EINVAL;
2914
2915 csr &= ~PCI_PM_CTRL_STATE_MASK;
2916 csr |= PCI_D3hot;
2917 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
2918 pci_dev_d3_sleep(dev);
2919
2920 csr &= ~PCI_PM_CTRL_STATE_MASK;
2921 csr |= PCI_D0;
2922 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
2923 pci_dev_d3_sleep(dev);
2924
2925 return 0;
2926}
2927
2928static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
2929{
2930 u16 ctrl;
2931 struct pci_dev *pdev;
2932
2933 if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self)
2934 return -ENOTTY;
2935
2936 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
2937 if (pdev != dev)
2938 return -ENOTTY;
2939
2940 if (probe)
2941 return 0;
2942
2943 pci_read_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, &ctrl);
2944 ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
2945 pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
2946 msleep(100);
2947
2948 ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
2949 pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
2950 msleep(100);
2951
2952 return 0;
2953}
2954
2955static int pci_dev_reset(struct pci_dev *dev, int probe)
2956{
2957 int rc;
2958
2959 might_sleep();
2960
2961 if (!probe) {
2962 pci_block_user_cfg_access(dev);
2963 /* block PM suspend, driver probe, etc. */
2964 device_lock(&dev->dev);
2965 }
2966
2967 rc = pci_dev_specific_reset(dev, probe);
2968 if (rc != -ENOTTY)
2969 goto done;
2970
2971 rc = pcie_flr(dev, probe);
2972 if (rc != -ENOTTY)
2973 goto done;
2974
2975 rc = pci_af_flr(dev, probe);
2976 if (rc != -ENOTTY)
2977 goto done;
2978
2979 rc = pci_pm_reset(dev, probe);
2980 if (rc != -ENOTTY)
2981 goto done;
2982
2983 rc = pci_parent_bus_reset(dev, probe);
2984done:
2985 if (!probe) {
2986 device_unlock(&dev->dev);
2987 pci_unblock_user_cfg_access(dev);
2988 }
2989
2990 return rc;
2991}
2992
2993/**
2994 * __pci_reset_function - reset a PCI device function
2995 * @dev: PCI device to reset
2996 *
2997 * Some devices allow an individual function to be reset without affecting
2998 * other functions in the same device. The PCI device must be responsive
2999 * to PCI config space in order to use this function.
3000 *
3001 * The device function is presumed to be unused when this function is called.
3002 * Resetting the device will make the contents of PCI configuration space
3003 * random, so any caller of this must be prepared to reinitialise the
3004 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
3005 * etc.
3006 *
3007 * Returns 0 if the device function was successfully reset or negative if the
3008 * device doesn't support resetting a single function.
3009 */
3010int __pci_reset_function(struct pci_dev *dev)
3011{
3012 return pci_dev_reset(dev, 0);
3013}
3014EXPORT_SYMBOL_GPL(__pci_reset_function);
3015
3016/**
3017 * pci_probe_reset_function - check whether the device can be safely reset
3018 * @dev: PCI device to reset
3019 *
3020 * Some devices allow an individual function to be reset without affecting
3021 * other functions in the same device. The PCI device must be responsive
3022 * to PCI config space in order to use this function.
3023 *
3024 * Returns 0 if the device function can be reset or negative if the
3025 * device doesn't support resetting a single function.
3026 */
3027int pci_probe_reset_function(struct pci_dev *dev)
3028{
3029 return pci_dev_reset(dev, 1);
3030}
3031
3032/**
3033 * pci_reset_function - quiesce and reset a PCI device function
3034 * @dev: PCI device to reset
3035 *
3036 * Some devices allow an individual function to be reset without affecting
3037 * other functions in the same device. The PCI device must be responsive
3038 * to PCI config space in order to use this function.
3039 *
3040 * This function does not just reset the PCI portion of a device, but
3041 * clears all the state associated with the device. This function differs
3042 * from __pci_reset_function in that it saves and restores device state
3043 * over the reset.
3044 *
3045 * Returns 0 if the device function was successfully reset or negative if the
3046 * device doesn't support resetting a single function.
3047 */
3048int pci_reset_function(struct pci_dev *dev)
3049{
3050 int rc;
3051
3052 rc = pci_dev_reset(dev, 1);
3053 if (rc)
3054 return rc;
3055
3056 pci_save_state(dev);
3057
3058 /*
3059 * both INTx and MSI are disabled after the Interrupt Disable bit
3060 * is set and the Bus Master bit is cleared.
3061 */
3062 pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
3063
3064 rc = pci_dev_reset(dev, 0);
3065
3066 pci_restore_state(dev);
3067
3068 return rc;
3069}
3070EXPORT_SYMBOL_GPL(pci_reset_function);
3071
3072/**
3073 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
3074 * @dev: PCI device to query
3075 *
3076 * Returns mmrbc: maximum designed memory read count in bytes
3077 * or appropriate error value.
3078 */
3079int pcix_get_max_mmrbc(struct pci_dev *dev)
3080{
3081 int cap;
3082 u32 stat;
3083
3084 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3085 if (!cap)
3086 return -EINVAL;
3087
3088 if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
3089 return -EINVAL;
3090
3091 return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21);
3092}
3093EXPORT_SYMBOL(pcix_get_max_mmrbc);
3094
3095/**
3096 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
3097 * @dev: PCI device to query
3098 *
3099 * Returns mmrbc: maximum memory read count in bytes
3100 * or appropriate error value.
3101 */
3102int pcix_get_mmrbc(struct pci_dev *dev)
3103{
3104 int cap;
3105 u16 cmd;
3106
3107 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3108 if (!cap)
3109 return -EINVAL;
3110
3111 if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
3112 return -EINVAL;
3113
3114 return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
3115}
3116EXPORT_SYMBOL(pcix_get_mmrbc);
3117
3118/**
3119 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
3120 * @dev: PCI device to query
3121 * @mmrbc: maximum memory read count in bytes
3122 * valid values are 512, 1024, 2048, 4096
3123 *
3124 * If possible sets maximum memory read byte count, some bridges have erratas
3125 * that prevent this.
3126 */
3127int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
3128{
3129 int cap;
3130 u32 stat, v, o;
3131 u16 cmd;
3132
3133 if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
3134 return -EINVAL;
3135
3136 v = ffs(mmrbc) - 10;
3137
3138 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3139 if (!cap)
3140 return -EINVAL;
3141
3142 if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
3143 return -EINVAL;
3144
3145 if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
3146 return -E2BIG;
3147
3148 if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
3149 return -EINVAL;
3150
3151 o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
3152 if (o != v) {
3153 if (v > o && dev->bus &&
3154 (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
3155 return -EIO;
3156
3157 cmd &= ~PCI_X_CMD_MAX_READ;
3158 cmd |= v << 2;
3159 if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd))
3160 return -EIO;
3161 }
3162 return 0;
3163}
3164EXPORT_SYMBOL(pcix_set_mmrbc);
3165
3166/**
3167 * pcie_get_readrq - get PCI Express read request size
3168 * @dev: PCI device to query
3169 *
3170 * Returns maximum memory read request in bytes
3171 * or appropriate error value.
3172 */
3173int pcie_get_readrq(struct pci_dev *dev)
3174{
3175 int ret, cap;
3176 u16 ctl;
3177
3178 cap = pci_pcie_cap(dev);
3179 if (!cap)
3180 return -EINVAL;
3181
3182 ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
3183 if (!ret)
3184 ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
3185
3186 return ret;
3187}
3188EXPORT_SYMBOL(pcie_get_readrq);
3189
3190/**
3191 * pcie_set_readrq - set PCI Express maximum memory read request
3192 * @dev: PCI device to query
3193 * @rq: maximum memory read count in bytes
3194 * valid values are 128, 256, 512, 1024, 2048, 4096
3195 *
3196 * If possible sets maximum memory read request in bytes
3197 */
3198int pcie_set_readrq(struct pci_dev *dev, int rq)
3199{
3200 int cap, err = -EINVAL;
3201 u16 ctl, v;
3202
3203 if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
3204 goto out;
3205
3206 v = (ffs(rq) - 8) << 12;
3207
3208 cap = pci_pcie_cap(dev);
3209 if (!cap)
3210 goto out;
3211
3212 err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
3213 if (err)
3214 goto out;
3215
3216 if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
3217 ctl &= ~PCI_EXP_DEVCTL_READRQ;
3218 ctl |= v;
3219 err = pci_write_config_word(dev, cap + PCI_EXP_DEVCTL, ctl);
3220 }
3221
3222out:
3223 return err;
3224}
3225EXPORT_SYMBOL(pcie_set_readrq);
3226
3227/**
3228 * pcie_get_mps - get PCI Express maximum payload size
3229 * @dev: PCI device to query
3230 *
3231 * Returns maximum payload size in bytes
3232 * or appropriate error value.
3233 */
3234int pcie_get_mps(struct pci_dev *dev)
3235{
3236 int ret, cap;
3237 u16 ctl;
3238
3239 cap = pci_pcie_cap(dev);
3240 if (!cap)
3241 return -EINVAL;
3242
3243 ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
3244 if (!ret)
3245 ret = 128 << ((ctl & PCI_EXP_DEVCTL_PAYLOAD) >> 5);
3246
3247 return ret;
3248}
3249
3250/**
3251 * pcie_set_mps - set PCI Express maximum payload size
3252 * @dev: PCI device to query
3253 * @mps: maximum payload size in bytes
3254 * valid values are 128, 256, 512, 1024, 2048, 4096
3255 *
3256 * If possible sets maximum payload size
3257 */
3258int pcie_set_mps(struct pci_dev *dev, int mps)
3259{
3260 int cap, err = -EINVAL;
3261 u16 ctl, v;
3262
3263 if (mps < 128 || mps > 4096 || !is_power_of_2(mps))
3264 goto out;
3265
3266 v = ffs(mps) - 8;
3267 if (v > dev->pcie_mpss)
3268 goto out;
3269 v <<= 5;
3270
3271 cap = pci_pcie_cap(dev);
3272 if (!cap)
3273 goto out;
3274
3275 err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
3276 if (err)
3277 goto out;
3278
3279 if ((ctl & PCI_EXP_DEVCTL_PAYLOAD) != v) {
3280 ctl &= ~PCI_EXP_DEVCTL_PAYLOAD;
3281 ctl |= v;
3282 err = pci_write_config_word(dev, cap + PCI_EXP_DEVCTL, ctl);
3283 }
3284out:
3285 return err;
3286}
3287
3288/**
3289 * pci_select_bars - Make BAR mask from the type of resource
3290 * @dev: the PCI device for which BAR mask is made
3291 * @flags: resource type mask to be selected
3292 *
3293 * This helper routine makes bar mask from the type of resource.
3294 */
3295int pci_select_bars(struct pci_dev *dev, unsigned long flags)
3296{
3297 int i, bars = 0;
3298 for (i = 0; i < PCI_NUM_RESOURCES; i++)
3299 if (pci_resource_flags(dev, i) & flags)
3300 bars |= (1 << i);
3301 return bars;
3302}
3303
3304/**
3305 * pci_resource_bar - get position of the BAR associated with a resource
3306 * @dev: the PCI device
3307 * @resno: the resource number
3308 * @type: the BAR type to be filled in
3309 *
3310 * Returns BAR position in config space, or 0 if the BAR is invalid.
3311 */
3312int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type)
3313{
3314 int reg;
3315
3316 if (resno < PCI_ROM_RESOURCE) {
3317 *type = pci_bar_unknown;
3318 return PCI_BASE_ADDRESS_0 + 4 * resno;
3319 } else if (resno == PCI_ROM_RESOURCE) {
3320 *type = pci_bar_mem32;
3321 return dev->rom_base_reg;
3322 } else if (resno < PCI_BRIDGE_RESOURCES) {
3323 /* device specific resource */
3324 reg = pci_iov_resource_bar(dev, resno, type);
3325 if (reg)
3326 return reg;
3327 }
3328
3329 dev_err(&dev->dev, "BAR %d: invalid resource\n", resno);
3330 return 0;
3331}
3332
3333/* Some architectures require additional programming to enable VGA */
3334static arch_set_vga_state_t arch_set_vga_state;
3335
3336void __init pci_register_set_vga_state(arch_set_vga_state_t func)
3337{
3338 arch_set_vga_state = func; /* NULL disables */
3339}
3340
3341static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode,
3342 unsigned int command_bits, u32 flags)
3343{
3344 if (arch_set_vga_state)
3345 return arch_set_vga_state(dev, decode, command_bits,
3346 flags);
3347 return 0;
3348}
3349
3350/**
3351 * pci_set_vga_state - set VGA decode state on device and parents if requested
3352 * @dev: the PCI device
3353 * @decode: true = enable decoding, false = disable decoding
3354 * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
3355 * @flags: traverse ancestors and change bridges
3356 * CHANGE_BRIDGE_ONLY / CHANGE_BRIDGE
3357 */
3358int pci_set_vga_state(struct pci_dev *dev, bool decode,
3359 unsigned int command_bits, u32 flags)
3360{
3361 struct pci_bus *bus;
3362 struct pci_dev *bridge;
3363 u16 cmd;
3364 int rc;
3365
3366 WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) & (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY)));
3367
3368 /* ARCH specific VGA enables */
3369 rc = pci_set_vga_state_arch(dev, decode, command_bits, flags);
3370 if (rc)
3371 return rc;
3372
3373 if (flags & PCI_VGA_STATE_CHANGE_DECODES) {
3374 pci_read_config_word(dev, PCI_COMMAND, &cmd);
3375 if (decode == true)
3376 cmd |= command_bits;
3377 else
3378 cmd &= ~command_bits;
3379 pci_write_config_word(dev, PCI_COMMAND, cmd);
3380 }
3381
3382 if (!(flags & PCI_VGA_STATE_CHANGE_BRIDGE))
3383 return 0;
3384
3385 bus = dev->bus;
3386 while (bus) {
3387 bridge = bus->self;
3388 if (bridge) {
3389 pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
3390 &cmd);
3391 if (decode == true)
3392 cmd |= PCI_BRIDGE_CTL_VGA;
3393 else
3394 cmd &= ~PCI_BRIDGE_CTL_VGA;
3395 pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
3396 cmd);
3397 }
3398 bus = bus->parent;
3399 }
3400 return 0;
3401}
3402
3403#define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
3404static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
3405static DEFINE_SPINLOCK(resource_alignment_lock);
3406
3407/**
3408 * pci_specified_resource_alignment - get resource alignment specified by user.
3409 * @dev: the PCI device to get
3410 *
3411 * RETURNS: Resource alignment if it is specified.
3412 * Zero if it is not specified.
3413 */
3414resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
3415{
3416 int seg, bus, slot, func, align_order, count;
3417 resource_size_t align = 0;
3418 char *p;
3419
3420 spin_lock(&resource_alignment_lock);
3421 p = resource_alignment_param;
3422 while (*p) {
3423 count = 0;
3424 if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
3425 p[count] == '@') {
3426 p += count + 1;
3427 } else {
3428 align_order = -1;
3429 }
3430 if (sscanf(p, "%x:%x:%x.%x%n",
3431 &seg, &bus, &slot, &func, &count) != 4) {
3432 seg = 0;
3433 if (sscanf(p, "%x:%x.%x%n",
3434 &bus, &slot, &func, &count) != 3) {
3435 /* Invalid format */
3436 printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
3437 p);
3438 break;
3439 }
3440 }
3441 p += count;
3442 if (seg == pci_domain_nr(dev->bus) &&
3443 bus == dev->bus->number &&
3444 slot == PCI_SLOT(dev->devfn) &&
3445 func == PCI_FUNC(dev->devfn)) {
3446 if (align_order == -1) {
3447 align = PAGE_SIZE;
3448 } else {
3449 align = 1 << align_order;
3450 }
3451 /* Found */
3452 break;
3453 }
3454 if (*p != ';' && *p != ',') {
3455 /* End of param or invalid format */
3456 break;
3457 }
3458 p++;
3459 }
3460 spin_unlock(&resource_alignment_lock);
3461 return align;
3462}
3463
3464/**
3465 * pci_is_reassigndev - check if specified PCI is target device to reassign
3466 * @dev: the PCI device to check
3467 *
3468 * RETURNS: non-zero for PCI device is a target device to reassign,
3469 * or zero is not.
3470 */
3471int pci_is_reassigndev(struct pci_dev *dev)
3472{
3473 return (pci_specified_resource_alignment(dev) != 0);
3474}
3475
3476ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
3477{
3478 if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
3479 count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
3480 spin_lock(&resource_alignment_lock);
3481 strncpy(resource_alignment_param, buf, count);
3482 resource_alignment_param[count] = '\0';
3483 spin_unlock(&resource_alignment_lock);
3484 return count;
3485}
3486
3487ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
3488{
3489 size_t count;
3490 spin_lock(&resource_alignment_lock);
3491 count = snprintf(buf, size, "%s", resource_alignment_param);
3492 spin_unlock(&resource_alignment_lock);
3493 return count;
3494}
3495
3496static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
3497{
3498 return pci_get_resource_alignment_param(buf, PAGE_SIZE);
3499}
3500
3501static ssize_t pci_resource_alignment_store(struct bus_type *bus,
3502 const char *buf, size_t count)
3503{
3504 return pci_set_resource_alignment_param(buf, count);
3505}
3506
3507BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
3508 pci_resource_alignment_store);
3509
3510static int __init pci_resource_alignment_sysfs_init(void)
3511{
3512 return bus_create_file(&pci_bus_type,
3513 &bus_attr_resource_alignment);
3514}
3515
3516late_initcall(pci_resource_alignment_sysfs_init);
3517
3518static void __devinit pci_no_domains(void)
3519{
3520#ifdef CONFIG_PCI_DOMAINS
3521 pci_domains_supported = 0;
3522#endif
3523}
3524
3525/**
3526 * pci_ext_cfg_enabled - can we access extended PCI config space?
3527 * @dev: The PCI device of the root bridge.
3528 *
3529 * Returns 1 if we can access PCI extended config space (offsets
3530 * greater than 0xff). This is the default implementation. Architecture
3531 * implementations can override this.
3532 */
3533int __attribute__ ((weak)) pci_ext_cfg_avail(struct pci_dev *dev)
3534{
3535 return 1;
3536}
3537
3538void __weak pci_fixup_cardbus(struct pci_bus *bus)
3539{
3540}
3541EXPORT_SYMBOL(pci_fixup_cardbus);
3542
3543static int __init pci_setup(char *str)
3544{
3545 while (str) {
3546 char *k = strchr(str, ',');
3547 if (k)
3548 *k++ = 0;
3549 if (*str && (str = pcibios_setup(str)) && *str) {
3550 if (!strcmp(str, "nomsi")) {
3551 pci_no_msi();
3552 } else if (!strcmp(str, "noaer")) {
3553 pci_no_aer();
3554 } else if (!strncmp(str, "realloc", 7)) {
3555 pci_realloc();
3556 } else if (!strcmp(str, "nodomains")) {
3557 pci_no_domains();
3558 } else if (!strncmp(str, "cbiosize=", 9)) {
3559 pci_cardbus_io_size = memparse(str + 9, &str);
3560 } else if (!strncmp(str, "cbmemsize=", 10)) {
3561 pci_cardbus_mem_size = memparse(str + 10, &str);
3562 } else if (!strncmp(str, "resource_alignment=", 19)) {
3563 pci_set_resource_alignment_param(str + 19,
3564 strlen(str + 19));
3565 } else if (!strncmp(str, "ecrc=", 5)) {
3566 pcie_ecrc_get_policy(str + 5);
3567 } else if (!strncmp(str, "hpiosize=", 9)) {
3568 pci_hotplug_io_size = memparse(str + 9, &str);
3569 } else if (!strncmp(str, "hpmemsize=", 10)) {
3570 pci_hotplug_mem_size = memparse(str + 10, &str);
3571 } else if (!strncmp(str, "pcie_bus_tune_off", 17)) {
3572 pcie_bus_config = PCIE_BUS_TUNE_OFF;
3573 } else if (!strncmp(str, "pcie_bus_safe", 13)) {
3574 pcie_bus_config = PCIE_BUS_SAFE;
3575 } else if (!strncmp(str, "pcie_bus_perf", 13)) {
3576 pcie_bus_config = PCIE_BUS_PERFORMANCE;
3577 } else if (!strncmp(str, "pcie_bus_peer2peer", 18)) {
3578 pcie_bus_config = PCIE_BUS_PEER2PEER;
3579 } else {
3580 printk(KERN_ERR "PCI: Unknown option `%s'\n",
3581 str);
3582 }
3583 }
3584 str = k;
3585 }
3586 return 0;
3587}
3588early_param("pci", pci_setup);
3589
3590EXPORT_SYMBOL(pci_reenable_device);
3591EXPORT_SYMBOL(pci_enable_device_io);
3592EXPORT_SYMBOL(pci_enable_device_mem);
3593EXPORT_SYMBOL(pci_enable_device);
3594EXPORT_SYMBOL(pcim_enable_device);
3595EXPORT_SYMBOL(pcim_pin_device);
3596EXPORT_SYMBOL(pci_disable_device);
3597EXPORT_SYMBOL(pci_find_capability);
3598EXPORT_SYMBOL(pci_bus_find_capability);
3599EXPORT_SYMBOL(pci_release_regions);
3600EXPORT_SYMBOL(pci_request_regions);
3601EXPORT_SYMBOL(pci_request_regions_exclusive);
3602EXPORT_SYMBOL(pci_release_region);
3603EXPORT_SYMBOL(pci_request_region);
3604EXPORT_SYMBOL(pci_request_region_exclusive);
3605EXPORT_SYMBOL(pci_release_selected_regions);
3606EXPORT_SYMBOL(pci_request_selected_regions);
3607EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
3608EXPORT_SYMBOL(pci_set_master);
3609EXPORT_SYMBOL(pci_clear_master);
3610EXPORT_SYMBOL(pci_set_mwi);
3611EXPORT_SYMBOL(pci_try_set_mwi);
3612EXPORT_SYMBOL(pci_clear_mwi);
3613EXPORT_SYMBOL_GPL(pci_intx);
3614EXPORT_SYMBOL(pci_assign_resource);
3615EXPORT_SYMBOL(pci_find_parent_resource);
3616EXPORT_SYMBOL(pci_select_bars);
3617
3618EXPORT_SYMBOL(pci_set_power_state);
3619EXPORT_SYMBOL(pci_save_state);
3620EXPORT_SYMBOL(pci_restore_state);
3621EXPORT_SYMBOL(pci_pme_capable);
3622EXPORT_SYMBOL(pci_pme_active);
3623EXPORT_SYMBOL(pci_wake_from_d3);
3624EXPORT_SYMBOL(pci_target_state);
3625EXPORT_SYMBOL(pci_prepare_to_sleep);
3626EXPORT_SYMBOL(pci_back_from_sleep);
3627EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
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 <linux/pci_hotplug.h>
26#include <asm-generic/pci-bridge.h>
27#include <asm/setup.h>
28#include "pci.h"
29
30const char *pci_power_names[] = {
31 "error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
32};
33EXPORT_SYMBOL_GPL(pci_power_names);
34
35int isa_dma_bridge_buggy;
36EXPORT_SYMBOL(isa_dma_bridge_buggy);
37
38int pci_pci_problems;
39EXPORT_SYMBOL(pci_pci_problems);
40
41unsigned int pci_pm_d3_delay;
42
43static void pci_pme_list_scan(struct work_struct *work);
44
45static LIST_HEAD(pci_pme_list);
46static DEFINE_MUTEX(pci_pme_list_mutex);
47static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan);
48
49struct pci_pme_device {
50 struct list_head list;
51 struct pci_dev *dev;
52};
53
54#define PME_TIMEOUT 1000 /* How long between PME checks */
55
56static void pci_dev_d3_sleep(struct pci_dev *dev)
57{
58 unsigned int delay = dev->d3_delay;
59
60 if (delay < pci_pm_d3_delay)
61 delay = pci_pm_d3_delay;
62
63 msleep(delay);
64}
65
66#ifdef CONFIG_PCI_DOMAINS
67int pci_domains_supported = 1;
68#endif
69
70#define DEFAULT_CARDBUS_IO_SIZE (256)
71#define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
72/* pci=cbmemsize=nnM,cbiosize=nn can override this */
73unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
74unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
75
76#define DEFAULT_HOTPLUG_IO_SIZE (256)
77#define DEFAULT_HOTPLUG_MEM_SIZE (2*1024*1024)
78/* pci=hpmemsize=nnM,hpiosize=nn can override this */
79unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE;
80unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
81
82enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_TUNE_OFF;
83
84/*
85 * The default CLS is used if arch didn't set CLS explicitly and not
86 * all pci devices agree on the same value. Arch can override either
87 * the dfl or actual value as it sees fit. Don't forget this is
88 * measured in 32-bit words, not bytes.
89 */
90u8 pci_dfl_cache_line_size = L1_CACHE_BYTES >> 2;
91u8 pci_cache_line_size;
92
93/*
94 * If we set up a device for bus mastering, we need to check the latency
95 * timer as certain BIOSes forget to set it properly.
96 */
97unsigned int pcibios_max_latency = 255;
98
99/* If set, the PCIe ARI capability will not be used. */
100static bool pcie_ari_disabled;
101
102/**
103 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
104 * @bus: pointer to PCI bus structure to search
105 *
106 * Given a PCI bus, returns the highest PCI bus number present in the set
107 * including the given PCI bus and its list of child PCI buses.
108 */
109unsigned char pci_bus_max_busnr(struct pci_bus* bus)
110{
111 struct pci_bus *tmp;
112 unsigned char max, n;
113
114 max = bus->busn_res.end;
115 list_for_each_entry(tmp, &bus->children, node) {
116 n = pci_bus_max_busnr(tmp);
117 if(n > max)
118 max = n;
119 }
120 return max;
121}
122EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
123
124#ifdef CONFIG_HAS_IOMEM
125void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
126{
127 /*
128 * Make sure the BAR is actually a memory resource, not an IO resource
129 */
130 if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
131 WARN_ON(1);
132 return NULL;
133 }
134 return ioremap_nocache(pci_resource_start(pdev, bar),
135 pci_resource_len(pdev, bar));
136}
137EXPORT_SYMBOL_GPL(pci_ioremap_bar);
138#endif
139
140#define PCI_FIND_CAP_TTL 48
141
142static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
143 u8 pos, int cap, int *ttl)
144{
145 u8 id;
146
147 while ((*ttl)--) {
148 pci_bus_read_config_byte(bus, devfn, pos, &pos);
149 if (pos < 0x40)
150 break;
151 pos &= ~3;
152 pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
153 &id);
154 if (id == 0xff)
155 break;
156 if (id == cap)
157 return pos;
158 pos += PCI_CAP_LIST_NEXT;
159 }
160 return 0;
161}
162
163static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
164 u8 pos, int cap)
165{
166 int ttl = PCI_FIND_CAP_TTL;
167
168 return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
169}
170
171int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
172{
173 return __pci_find_next_cap(dev->bus, dev->devfn,
174 pos + PCI_CAP_LIST_NEXT, cap);
175}
176EXPORT_SYMBOL_GPL(pci_find_next_capability);
177
178static int __pci_bus_find_cap_start(struct pci_bus *bus,
179 unsigned int devfn, u8 hdr_type)
180{
181 u16 status;
182
183 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
184 if (!(status & PCI_STATUS_CAP_LIST))
185 return 0;
186
187 switch (hdr_type) {
188 case PCI_HEADER_TYPE_NORMAL:
189 case PCI_HEADER_TYPE_BRIDGE:
190 return PCI_CAPABILITY_LIST;
191 case PCI_HEADER_TYPE_CARDBUS:
192 return PCI_CB_CAPABILITY_LIST;
193 default:
194 return 0;
195 }
196
197 return 0;
198}
199
200/**
201 * pci_find_capability - query for devices' capabilities
202 * @dev: PCI device to query
203 * @cap: capability code
204 *
205 * Tell if a device supports a given PCI capability.
206 * Returns the address of the requested capability structure within the
207 * device's PCI configuration space or 0 in case the device does not
208 * support it. Possible values for @cap:
209 *
210 * %PCI_CAP_ID_PM Power Management
211 * %PCI_CAP_ID_AGP Accelerated Graphics Port
212 * %PCI_CAP_ID_VPD Vital Product Data
213 * %PCI_CAP_ID_SLOTID Slot Identification
214 * %PCI_CAP_ID_MSI Message Signalled Interrupts
215 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
216 * %PCI_CAP_ID_PCIX PCI-X
217 * %PCI_CAP_ID_EXP PCI Express
218 */
219int pci_find_capability(struct pci_dev *dev, int cap)
220{
221 int pos;
222
223 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
224 if (pos)
225 pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
226
227 return pos;
228}
229
230/**
231 * pci_bus_find_capability - query for devices' capabilities
232 * @bus: the PCI bus to query
233 * @devfn: PCI device to query
234 * @cap: capability code
235 *
236 * Like pci_find_capability() but works for pci devices that do not have a
237 * pci_dev structure set up yet.
238 *
239 * Returns the address of the requested capability structure within the
240 * device's PCI configuration space or 0 in case the device does not
241 * support it.
242 */
243int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
244{
245 int pos;
246 u8 hdr_type;
247
248 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
249
250 pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
251 if (pos)
252 pos = __pci_find_next_cap(bus, devfn, pos, cap);
253
254 return pos;
255}
256
257/**
258 * pci_find_next_ext_capability - Find an extended capability
259 * @dev: PCI device to query
260 * @start: address at which to start looking (0 to start at beginning of list)
261 * @cap: capability code
262 *
263 * Returns the address of the next matching extended capability structure
264 * within the device's PCI configuration space or 0 if the device does
265 * not support it. Some capabilities can occur several times, e.g., the
266 * vendor-specific capability, and this provides a way to find them all.
267 */
268int pci_find_next_ext_capability(struct pci_dev *dev, int start, int cap)
269{
270 u32 header;
271 int ttl;
272 int pos = PCI_CFG_SPACE_SIZE;
273
274 /* minimum 8 bytes per capability */
275 ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
276
277 if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
278 return 0;
279
280 if (start)
281 pos = start;
282
283 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
284 return 0;
285
286 /*
287 * If we have no capabilities, this is indicated by cap ID,
288 * cap version and next pointer all being 0.
289 */
290 if (header == 0)
291 return 0;
292
293 while (ttl-- > 0) {
294 if (PCI_EXT_CAP_ID(header) == cap && pos != start)
295 return pos;
296
297 pos = PCI_EXT_CAP_NEXT(header);
298 if (pos < PCI_CFG_SPACE_SIZE)
299 break;
300
301 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
302 break;
303 }
304
305 return 0;
306}
307EXPORT_SYMBOL_GPL(pci_find_next_ext_capability);
308
309/**
310 * pci_find_ext_capability - Find an extended capability
311 * @dev: PCI device to query
312 * @cap: capability code
313 *
314 * Returns the address of the requested extended capability structure
315 * within the device's PCI configuration space or 0 if the device does
316 * not support it. Possible values for @cap:
317 *
318 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
319 * %PCI_EXT_CAP_ID_VC Virtual Channel
320 * %PCI_EXT_CAP_ID_DSN Device Serial Number
321 * %PCI_EXT_CAP_ID_PWR Power Budgeting
322 */
323int pci_find_ext_capability(struct pci_dev *dev, int cap)
324{
325 return pci_find_next_ext_capability(dev, 0, cap);
326}
327EXPORT_SYMBOL_GPL(pci_find_ext_capability);
328
329static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
330{
331 int rc, ttl = PCI_FIND_CAP_TTL;
332 u8 cap, mask;
333
334 if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
335 mask = HT_3BIT_CAP_MASK;
336 else
337 mask = HT_5BIT_CAP_MASK;
338
339 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
340 PCI_CAP_ID_HT, &ttl);
341 while (pos) {
342 rc = pci_read_config_byte(dev, pos + 3, &cap);
343 if (rc != PCIBIOS_SUCCESSFUL)
344 return 0;
345
346 if ((cap & mask) == ht_cap)
347 return pos;
348
349 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
350 pos + PCI_CAP_LIST_NEXT,
351 PCI_CAP_ID_HT, &ttl);
352 }
353
354 return 0;
355}
356/**
357 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
358 * @dev: PCI device to query
359 * @pos: Position from which to continue searching
360 * @ht_cap: Hypertransport capability code
361 *
362 * To be used in conjunction with pci_find_ht_capability() to search for
363 * all capabilities matching @ht_cap. @pos should always be a value returned
364 * from pci_find_ht_capability().
365 *
366 * NB. To be 100% safe against broken PCI devices, the caller should take
367 * steps to avoid an infinite loop.
368 */
369int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
370{
371 return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
372}
373EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
374
375/**
376 * pci_find_ht_capability - query a device's Hypertransport capabilities
377 * @dev: PCI device to query
378 * @ht_cap: Hypertransport capability code
379 *
380 * Tell if a device supports a given Hypertransport capability.
381 * Returns an address within the device's PCI configuration space
382 * or 0 in case the device does not support the request capability.
383 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
384 * which has a Hypertransport capability matching @ht_cap.
385 */
386int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
387{
388 int pos;
389
390 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
391 if (pos)
392 pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
393
394 return pos;
395}
396EXPORT_SYMBOL_GPL(pci_find_ht_capability);
397
398/**
399 * pci_find_parent_resource - return resource region of parent bus of given region
400 * @dev: PCI device structure contains resources to be searched
401 * @res: child resource record for which parent is sought
402 *
403 * For given resource region of given device, return the resource
404 * region of parent bus the given region is contained in.
405 */
406struct resource *
407pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
408{
409 const struct pci_bus *bus = dev->bus;
410 struct resource *r;
411 int i;
412
413 pci_bus_for_each_resource(bus, r, i) {
414 if (!r)
415 continue;
416 if (res->start && resource_contains(r, res)) {
417
418 /*
419 * If the window is prefetchable but the BAR is
420 * not, the allocator made a mistake.
421 */
422 if (r->flags & IORESOURCE_PREFETCH &&
423 !(res->flags & IORESOURCE_PREFETCH))
424 return NULL;
425
426 /*
427 * If we're below a transparent bridge, there may
428 * be both a positively-decoded aperture and a
429 * subtractively-decoded region that contain the BAR.
430 * We want the positively-decoded one, so this depends
431 * on pci_bus_for_each_resource() giving us those
432 * first.
433 */
434 return r;
435 }
436 }
437 return NULL;
438}
439
440/**
441 * pci_wait_for_pending - wait for @mask bit(s) to clear in status word @pos
442 * @dev: the PCI device to operate on
443 * @pos: config space offset of status word
444 * @mask: mask of bit(s) to care about in status word
445 *
446 * Return 1 when mask bit(s) in status word clear, 0 otherwise.
447 */
448int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask)
449{
450 int i;
451
452 /* Wait for Transaction Pending bit clean */
453 for (i = 0; i < 4; i++) {
454 u16 status;
455 if (i)
456 msleep((1 << (i - 1)) * 100);
457
458 pci_read_config_word(dev, pos, &status);
459 if (!(status & mask))
460 return 1;
461 }
462
463 return 0;
464}
465
466/**
467 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
468 * @dev: PCI device to have its BARs restored
469 *
470 * Restore the BAR values for a given device, so as to make it
471 * accessible by its driver.
472 */
473static void
474pci_restore_bars(struct pci_dev *dev)
475{
476 int i;
477
478 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
479 pci_update_resource(dev, i);
480}
481
482static struct pci_platform_pm_ops *pci_platform_pm;
483
484int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
485{
486 if (!ops->is_manageable || !ops->set_state || !ops->choose_state
487 || !ops->sleep_wake)
488 return -EINVAL;
489 pci_platform_pm = ops;
490 return 0;
491}
492
493static inline bool platform_pci_power_manageable(struct pci_dev *dev)
494{
495 return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
496}
497
498static inline int platform_pci_set_power_state(struct pci_dev *dev,
499 pci_power_t t)
500{
501 return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
502}
503
504static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
505{
506 return pci_platform_pm ?
507 pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
508}
509
510static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
511{
512 return pci_platform_pm ?
513 pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
514}
515
516static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable)
517{
518 return pci_platform_pm ?
519 pci_platform_pm->run_wake(dev, enable) : -ENODEV;
520}
521
522/**
523 * pci_raw_set_power_state - Use PCI PM registers to set the power state of
524 * given PCI device
525 * @dev: PCI device to handle.
526 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
527 *
528 * RETURN VALUE:
529 * -EINVAL if the requested state is invalid.
530 * -EIO if device does not support PCI PM or its PM capabilities register has a
531 * wrong version, or device doesn't support the requested state.
532 * 0 if device already is in the requested state.
533 * 0 if device's power state has been successfully changed.
534 */
535static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
536{
537 u16 pmcsr;
538 bool need_restore = false;
539
540 /* Check if we're already there */
541 if (dev->current_state == state)
542 return 0;
543
544 if (!dev->pm_cap)
545 return -EIO;
546
547 if (state < PCI_D0 || state > PCI_D3hot)
548 return -EINVAL;
549
550 /* Validate current state:
551 * Can enter D0 from any state, but if we can only go deeper
552 * to sleep if we're already in a low power state
553 */
554 if (state != PCI_D0 && dev->current_state <= PCI_D3cold
555 && dev->current_state > state) {
556 dev_err(&dev->dev, "invalid power transition "
557 "(from state %d to %d)\n", dev->current_state, state);
558 return -EINVAL;
559 }
560
561 /* check if this device supports the desired state */
562 if ((state == PCI_D1 && !dev->d1_support)
563 || (state == PCI_D2 && !dev->d2_support))
564 return -EIO;
565
566 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
567
568 /* If we're (effectively) in D3, force entire word to 0.
569 * This doesn't affect PME_Status, disables PME_En, and
570 * sets PowerState to 0.
571 */
572 switch (dev->current_state) {
573 case PCI_D0:
574 case PCI_D1:
575 case PCI_D2:
576 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
577 pmcsr |= state;
578 break;
579 case PCI_D3hot:
580 case PCI_D3cold:
581 case PCI_UNKNOWN: /* Boot-up */
582 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
583 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
584 need_restore = true;
585 /* Fall-through: force to D0 */
586 default:
587 pmcsr = 0;
588 break;
589 }
590
591 /* enter specified state */
592 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
593
594 /* Mandatory power management transition delays */
595 /* see PCI PM 1.1 5.6.1 table 18 */
596 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
597 pci_dev_d3_sleep(dev);
598 else if (state == PCI_D2 || dev->current_state == PCI_D2)
599 udelay(PCI_PM_D2_DELAY);
600
601 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
602 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
603 if (dev->current_state != state && printk_ratelimit())
604 dev_info(&dev->dev, "Refused to change power state, "
605 "currently in D%d\n", dev->current_state);
606
607 /*
608 * According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
609 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
610 * from D3hot to D0 _may_ perform an internal reset, thereby
611 * going to "D0 Uninitialized" rather than "D0 Initialized".
612 * For example, at least some versions of the 3c905B and the
613 * 3c556B exhibit this behaviour.
614 *
615 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
616 * devices in a D3hot state at boot. Consequently, we need to
617 * restore at least the BARs so that the device will be
618 * accessible to its driver.
619 */
620 if (need_restore)
621 pci_restore_bars(dev);
622
623 if (dev->bus->self)
624 pcie_aspm_pm_state_change(dev->bus->self);
625
626 return 0;
627}
628
629/**
630 * pci_update_current_state - Read PCI power state of given device from its
631 * PCI PM registers and cache it
632 * @dev: PCI device to handle.
633 * @state: State to cache in case the device doesn't have the PM capability
634 */
635void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
636{
637 if (dev->pm_cap) {
638 u16 pmcsr;
639
640 /*
641 * Configuration space is not accessible for device in
642 * D3cold, so just keep or set D3cold for safety
643 */
644 if (dev->current_state == PCI_D3cold)
645 return;
646 if (state == PCI_D3cold) {
647 dev->current_state = PCI_D3cold;
648 return;
649 }
650 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
651 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
652 } else {
653 dev->current_state = state;
654 }
655}
656
657/**
658 * pci_power_up - Put the given device into D0 forcibly
659 * @dev: PCI device to power up
660 */
661void pci_power_up(struct pci_dev *dev)
662{
663 if (platform_pci_power_manageable(dev))
664 platform_pci_set_power_state(dev, PCI_D0);
665
666 pci_raw_set_power_state(dev, PCI_D0);
667 pci_update_current_state(dev, PCI_D0);
668}
669
670/**
671 * pci_platform_power_transition - Use platform to change device power state
672 * @dev: PCI device to handle.
673 * @state: State to put the device into.
674 */
675static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
676{
677 int error;
678
679 if (platform_pci_power_manageable(dev)) {
680 error = platform_pci_set_power_state(dev, state);
681 if (!error)
682 pci_update_current_state(dev, state);
683 } else
684 error = -ENODEV;
685
686 if (error && !dev->pm_cap) /* Fall back to PCI_D0 */
687 dev->current_state = PCI_D0;
688
689 return error;
690}
691
692/**
693 * pci_wakeup - Wake up a PCI device
694 * @pci_dev: Device to handle.
695 * @ign: ignored parameter
696 */
697static int pci_wakeup(struct pci_dev *pci_dev, void *ign)
698{
699 pci_wakeup_event(pci_dev);
700 pm_request_resume(&pci_dev->dev);
701 return 0;
702}
703
704/**
705 * pci_wakeup_bus - Walk given bus and wake up devices on it
706 * @bus: Top bus of the subtree to walk.
707 */
708static void pci_wakeup_bus(struct pci_bus *bus)
709{
710 if (bus)
711 pci_walk_bus(bus, pci_wakeup, NULL);
712}
713
714/**
715 * __pci_start_power_transition - Start power transition of a PCI device
716 * @dev: PCI device to handle.
717 * @state: State to put the device into.
718 */
719static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
720{
721 if (state == PCI_D0) {
722 pci_platform_power_transition(dev, PCI_D0);
723 /*
724 * Mandatory power management transition delays, see
725 * PCI Express Base Specification Revision 2.0 Section
726 * 6.6.1: Conventional Reset. Do not delay for
727 * devices powered on/off by corresponding bridge,
728 * because have already delayed for the bridge.
729 */
730 if (dev->runtime_d3cold) {
731 msleep(dev->d3cold_delay);
732 /*
733 * When powering on a bridge from D3cold, the
734 * whole hierarchy may be powered on into
735 * D0uninitialized state, resume them to give
736 * them a chance to suspend again
737 */
738 pci_wakeup_bus(dev->subordinate);
739 }
740 }
741}
742
743/**
744 * __pci_dev_set_current_state - Set current state of a PCI device
745 * @dev: Device to handle
746 * @data: pointer to state to be set
747 */
748static int __pci_dev_set_current_state(struct pci_dev *dev, void *data)
749{
750 pci_power_t state = *(pci_power_t *)data;
751
752 dev->current_state = state;
753 return 0;
754}
755
756/**
757 * __pci_bus_set_current_state - Walk given bus and set current state of devices
758 * @bus: Top bus of the subtree to walk.
759 * @state: state to be set
760 */
761static void __pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
762{
763 if (bus)
764 pci_walk_bus(bus, __pci_dev_set_current_state, &state);
765}
766
767/**
768 * __pci_complete_power_transition - Complete power transition of a PCI device
769 * @dev: PCI device to handle.
770 * @state: State to put the device into.
771 *
772 * This function should not be called directly by device drivers.
773 */
774int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
775{
776 int ret;
777
778 if (state <= PCI_D0)
779 return -EINVAL;
780 ret = pci_platform_power_transition(dev, state);
781 /* Power off the bridge may power off the whole hierarchy */
782 if (!ret && state == PCI_D3cold)
783 __pci_bus_set_current_state(dev->subordinate, PCI_D3cold);
784 return ret;
785}
786EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
787
788/**
789 * pci_set_power_state - Set the power state of a PCI device
790 * @dev: PCI device to handle.
791 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
792 *
793 * Transition a device to a new power state, using the platform firmware and/or
794 * the device's PCI PM registers.
795 *
796 * RETURN VALUE:
797 * -EINVAL if the requested state is invalid.
798 * -EIO if device does not support PCI PM or its PM capabilities register has a
799 * wrong version, or device doesn't support the requested state.
800 * 0 if device already is in the requested state.
801 * 0 if device's power state has been successfully changed.
802 */
803int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
804{
805 int error;
806
807 /* bound the state we're entering */
808 if (state > PCI_D3cold)
809 state = PCI_D3cold;
810 else if (state < PCI_D0)
811 state = PCI_D0;
812 else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
813 /*
814 * If the device or the parent bridge do not support PCI PM,
815 * ignore the request if we're doing anything other than putting
816 * it into D0 (which would only happen on boot).
817 */
818 return 0;
819
820 /* Check if we're already there */
821 if (dev->current_state == state)
822 return 0;
823
824 __pci_start_power_transition(dev, state);
825
826 /* This device is quirked not to be put into D3, so
827 don't put it in D3 */
828 if (state >= PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
829 return 0;
830
831 /*
832 * To put device in D3cold, we put device into D3hot in native
833 * way, then put device into D3cold with platform ops
834 */
835 error = pci_raw_set_power_state(dev, state > PCI_D3hot ?
836 PCI_D3hot : state);
837
838 if (!__pci_complete_power_transition(dev, state))
839 error = 0;
840 /*
841 * When aspm_policy is "powersave" this call ensures
842 * that ASPM is configured.
843 */
844 if (!error && dev->bus->self)
845 pcie_aspm_powersave_config_link(dev->bus->self);
846
847 return error;
848}
849
850/**
851 * pci_choose_state - Choose the power state of a PCI device
852 * @dev: PCI device to be suspended
853 * @state: target sleep state for the whole system. This is the value
854 * that is passed to suspend() function.
855 *
856 * Returns PCI power state suitable for given device and given system
857 * message.
858 */
859
860pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
861{
862 pci_power_t ret;
863
864 if (!dev->pm_cap)
865 return PCI_D0;
866
867 ret = platform_pci_choose_state(dev);
868 if (ret != PCI_POWER_ERROR)
869 return ret;
870
871 switch (state.event) {
872 case PM_EVENT_ON:
873 return PCI_D0;
874 case PM_EVENT_FREEZE:
875 case PM_EVENT_PRETHAW:
876 /* REVISIT both freeze and pre-thaw "should" use D0 */
877 case PM_EVENT_SUSPEND:
878 case PM_EVENT_HIBERNATE:
879 return PCI_D3hot;
880 default:
881 dev_info(&dev->dev, "unrecognized suspend event %d\n",
882 state.event);
883 BUG();
884 }
885 return PCI_D0;
886}
887
888EXPORT_SYMBOL(pci_choose_state);
889
890#define PCI_EXP_SAVE_REGS 7
891
892
893static struct pci_cap_saved_state *_pci_find_saved_cap(struct pci_dev *pci_dev,
894 u16 cap, bool extended)
895{
896 struct pci_cap_saved_state *tmp;
897
898 hlist_for_each_entry(tmp, &pci_dev->saved_cap_space, next) {
899 if (tmp->cap.cap_extended == extended && tmp->cap.cap_nr == cap)
900 return tmp;
901 }
902 return NULL;
903}
904
905struct pci_cap_saved_state *pci_find_saved_cap(struct pci_dev *dev, char cap)
906{
907 return _pci_find_saved_cap(dev, cap, false);
908}
909
910struct pci_cap_saved_state *pci_find_saved_ext_cap(struct pci_dev *dev, u16 cap)
911{
912 return _pci_find_saved_cap(dev, cap, true);
913}
914
915static int pci_save_pcie_state(struct pci_dev *dev)
916{
917 int i = 0;
918 struct pci_cap_saved_state *save_state;
919 u16 *cap;
920
921 if (!pci_is_pcie(dev))
922 return 0;
923
924 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
925 if (!save_state) {
926 dev_err(&dev->dev, "buffer not found in %s\n", __func__);
927 return -ENOMEM;
928 }
929
930 cap = (u16 *)&save_state->cap.data[0];
931 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &cap[i++]);
932 pcie_capability_read_word(dev, PCI_EXP_LNKCTL, &cap[i++]);
933 pcie_capability_read_word(dev, PCI_EXP_SLTCTL, &cap[i++]);
934 pcie_capability_read_word(dev, PCI_EXP_RTCTL, &cap[i++]);
935 pcie_capability_read_word(dev, PCI_EXP_DEVCTL2, &cap[i++]);
936 pcie_capability_read_word(dev, PCI_EXP_LNKCTL2, &cap[i++]);
937 pcie_capability_read_word(dev, PCI_EXP_SLTCTL2, &cap[i++]);
938
939 return 0;
940}
941
942static void pci_restore_pcie_state(struct pci_dev *dev)
943{
944 int i = 0;
945 struct pci_cap_saved_state *save_state;
946 u16 *cap;
947
948 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
949 if (!save_state)
950 return;
951
952 cap = (u16 *)&save_state->cap.data[0];
953 pcie_capability_write_word(dev, PCI_EXP_DEVCTL, cap[i++]);
954 pcie_capability_write_word(dev, PCI_EXP_LNKCTL, cap[i++]);
955 pcie_capability_write_word(dev, PCI_EXP_SLTCTL, cap[i++]);
956 pcie_capability_write_word(dev, PCI_EXP_RTCTL, cap[i++]);
957 pcie_capability_write_word(dev, PCI_EXP_DEVCTL2, cap[i++]);
958 pcie_capability_write_word(dev, PCI_EXP_LNKCTL2, cap[i++]);
959 pcie_capability_write_word(dev, PCI_EXP_SLTCTL2, cap[i++]);
960}
961
962
963static int pci_save_pcix_state(struct pci_dev *dev)
964{
965 int pos;
966 struct pci_cap_saved_state *save_state;
967
968 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
969 if (pos <= 0)
970 return 0;
971
972 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
973 if (!save_state) {
974 dev_err(&dev->dev, "buffer not found in %s\n", __func__);
975 return -ENOMEM;
976 }
977
978 pci_read_config_word(dev, pos + PCI_X_CMD,
979 (u16 *)save_state->cap.data);
980
981 return 0;
982}
983
984static void pci_restore_pcix_state(struct pci_dev *dev)
985{
986 int i = 0, pos;
987 struct pci_cap_saved_state *save_state;
988 u16 *cap;
989
990 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
991 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
992 if (!save_state || pos <= 0)
993 return;
994 cap = (u16 *)&save_state->cap.data[0];
995
996 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
997}
998
999
1000/**
1001 * pci_save_state - save the PCI configuration space of a device before suspending
1002 * @dev: - PCI device that we're dealing with
1003 */
1004int
1005pci_save_state(struct pci_dev *dev)
1006{
1007 int i;
1008 /* XXX: 100% dword access ok here? */
1009 for (i = 0; i < 16; i++)
1010 pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
1011 dev->state_saved = true;
1012 if ((i = pci_save_pcie_state(dev)) != 0)
1013 return i;
1014 if ((i = pci_save_pcix_state(dev)) != 0)
1015 return i;
1016 if ((i = pci_save_vc_state(dev)) != 0)
1017 return i;
1018 return 0;
1019}
1020
1021static void pci_restore_config_dword(struct pci_dev *pdev, int offset,
1022 u32 saved_val, int retry)
1023{
1024 u32 val;
1025
1026 pci_read_config_dword(pdev, offset, &val);
1027 if (val == saved_val)
1028 return;
1029
1030 for (;;) {
1031 dev_dbg(&pdev->dev, "restoring config space at offset "
1032 "%#x (was %#x, writing %#x)\n", offset, val, saved_val);
1033 pci_write_config_dword(pdev, offset, saved_val);
1034 if (retry-- <= 0)
1035 return;
1036
1037 pci_read_config_dword(pdev, offset, &val);
1038 if (val == saved_val)
1039 return;
1040
1041 mdelay(1);
1042 }
1043}
1044
1045static void pci_restore_config_space_range(struct pci_dev *pdev,
1046 int start, int end, int retry)
1047{
1048 int index;
1049
1050 for (index = end; index >= start; index--)
1051 pci_restore_config_dword(pdev, 4 * index,
1052 pdev->saved_config_space[index],
1053 retry);
1054}
1055
1056static void pci_restore_config_space(struct pci_dev *pdev)
1057{
1058 if (pdev->hdr_type == PCI_HEADER_TYPE_NORMAL) {
1059 pci_restore_config_space_range(pdev, 10, 15, 0);
1060 /* Restore BARs before the command register. */
1061 pci_restore_config_space_range(pdev, 4, 9, 10);
1062 pci_restore_config_space_range(pdev, 0, 3, 0);
1063 } else {
1064 pci_restore_config_space_range(pdev, 0, 15, 0);
1065 }
1066}
1067
1068/**
1069 * pci_restore_state - Restore the saved state of a PCI device
1070 * @dev: - PCI device that we're dealing with
1071 */
1072void pci_restore_state(struct pci_dev *dev)
1073{
1074 if (!dev->state_saved)
1075 return;
1076
1077 /* PCI Express register must be restored first */
1078 pci_restore_pcie_state(dev);
1079 pci_restore_ats_state(dev);
1080 pci_restore_vc_state(dev);
1081
1082 pci_restore_config_space(dev);
1083
1084 pci_restore_pcix_state(dev);
1085 pci_restore_msi_state(dev);
1086 pci_restore_iov_state(dev);
1087
1088 dev->state_saved = false;
1089}
1090
1091struct pci_saved_state {
1092 u32 config_space[16];
1093 struct pci_cap_saved_data cap[0];
1094};
1095
1096/**
1097 * pci_store_saved_state - Allocate and return an opaque struct containing
1098 * the device saved state.
1099 * @dev: PCI device that we're dealing with
1100 *
1101 * Return NULL if no state or error.
1102 */
1103struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev)
1104{
1105 struct pci_saved_state *state;
1106 struct pci_cap_saved_state *tmp;
1107 struct pci_cap_saved_data *cap;
1108 size_t size;
1109
1110 if (!dev->state_saved)
1111 return NULL;
1112
1113 size = sizeof(*state) + sizeof(struct pci_cap_saved_data);
1114
1115 hlist_for_each_entry(tmp, &dev->saved_cap_space, next)
1116 size += sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1117
1118 state = kzalloc(size, GFP_KERNEL);
1119 if (!state)
1120 return NULL;
1121
1122 memcpy(state->config_space, dev->saved_config_space,
1123 sizeof(state->config_space));
1124
1125 cap = state->cap;
1126 hlist_for_each_entry(tmp, &dev->saved_cap_space, next) {
1127 size_t len = sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1128 memcpy(cap, &tmp->cap, len);
1129 cap = (struct pci_cap_saved_data *)((u8 *)cap + len);
1130 }
1131 /* Empty cap_save terminates list */
1132
1133 return state;
1134}
1135EXPORT_SYMBOL_GPL(pci_store_saved_state);
1136
1137/**
1138 * pci_load_saved_state - Reload the provided save state into struct pci_dev.
1139 * @dev: PCI device that we're dealing with
1140 * @state: Saved state returned from pci_store_saved_state()
1141 */
1142static int pci_load_saved_state(struct pci_dev *dev,
1143 struct pci_saved_state *state)
1144{
1145 struct pci_cap_saved_data *cap;
1146
1147 dev->state_saved = false;
1148
1149 if (!state)
1150 return 0;
1151
1152 memcpy(dev->saved_config_space, state->config_space,
1153 sizeof(state->config_space));
1154
1155 cap = state->cap;
1156 while (cap->size) {
1157 struct pci_cap_saved_state *tmp;
1158
1159 tmp = _pci_find_saved_cap(dev, cap->cap_nr, cap->cap_extended);
1160 if (!tmp || tmp->cap.size != cap->size)
1161 return -EINVAL;
1162
1163 memcpy(tmp->cap.data, cap->data, tmp->cap.size);
1164 cap = (struct pci_cap_saved_data *)((u8 *)cap +
1165 sizeof(struct pci_cap_saved_data) + cap->size);
1166 }
1167
1168 dev->state_saved = true;
1169 return 0;
1170}
1171
1172/**
1173 * pci_load_and_free_saved_state - Reload the save state pointed to by state,
1174 * and free the memory allocated for it.
1175 * @dev: PCI device that we're dealing with
1176 * @state: Pointer to saved state returned from pci_store_saved_state()
1177 */
1178int pci_load_and_free_saved_state(struct pci_dev *dev,
1179 struct pci_saved_state **state)
1180{
1181 int ret = pci_load_saved_state(dev, *state);
1182 kfree(*state);
1183 *state = NULL;
1184 return ret;
1185}
1186EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state);
1187
1188int __weak pcibios_enable_device(struct pci_dev *dev, int bars)
1189{
1190 return pci_enable_resources(dev, bars);
1191}
1192
1193static int do_pci_enable_device(struct pci_dev *dev, int bars)
1194{
1195 int err;
1196 u16 cmd;
1197 u8 pin;
1198
1199 err = pci_set_power_state(dev, PCI_D0);
1200 if (err < 0 && err != -EIO)
1201 return err;
1202 err = pcibios_enable_device(dev, bars);
1203 if (err < 0)
1204 return err;
1205 pci_fixup_device(pci_fixup_enable, dev);
1206
1207 if (dev->msi_enabled || dev->msix_enabled)
1208 return 0;
1209
1210 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1211 if (pin) {
1212 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1213 if (cmd & PCI_COMMAND_INTX_DISABLE)
1214 pci_write_config_word(dev, PCI_COMMAND,
1215 cmd & ~PCI_COMMAND_INTX_DISABLE);
1216 }
1217
1218 return 0;
1219}
1220
1221/**
1222 * pci_reenable_device - Resume abandoned device
1223 * @dev: PCI device to be resumed
1224 *
1225 * Note this function is a backend of pci_default_resume and is not supposed
1226 * to be called by normal code, write proper resume handler and use it instead.
1227 */
1228int pci_reenable_device(struct pci_dev *dev)
1229{
1230 if (pci_is_enabled(dev))
1231 return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
1232 return 0;
1233}
1234
1235static void pci_enable_bridge(struct pci_dev *dev)
1236{
1237 struct pci_dev *bridge;
1238 int retval;
1239
1240 bridge = pci_upstream_bridge(dev);
1241 if (bridge)
1242 pci_enable_bridge(bridge);
1243
1244 if (pci_is_enabled(dev)) {
1245 if (!dev->is_busmaster)
1246 pci_set_master(dev);
1247 return;
1248 }
1249
1250 retval = pci_enable_device(dev);
1251 if (retval)
1252 dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n",
1253 retval);
1254 pci_set_master(dev);
1255}
1256
1257static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags)
1258{
1259 struct pci_dev *bridge;
1260 int err;
1261 int i, bars = 0;
1262
1263 /*
1264 * Power state could be unknown at this point, either due to a fresh
1265 * boot or a device removal call. So get the current power state
1266 * so that things like MSI message writing will behave as expected
1267 * (e.g. if the device really is in D0 at enable time).
1268 */
1269 if (dev->pm_cap) {
1270 u16 pmcsr;
1271 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1272 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
1273 }
1274
1275 if (atomic_inc_return(&dev->enable_cnt) > 1)
1276 return 0; /* already enabled */
1277
1278 bridge = pci_upstream_bridge(dev);
1279 if (bridge)
1280 pci_enable_bridge(bridge);
1281
1282 /* only skip sriov related */
1283 for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1284 if (dev->resource[i].flags & flags)
1285 bars |= (1 << i);
1286 for (i = PCI_BRIDGE_RESOURCES; i < DEVICE_COUNT_RESOURCE; i++)
1287 if (dev->resource[i].flags & flags)
1288 bars |= (1 << i);
1289
1290 err = do_pci_enable_device(dev, bars);
1291 if (err < 0)
1292 atomic_dec(&dev->enable_cnt);
1293 return err;
1294}
1295
1296/**
1297 * pci_enable_device_io - Initialize a device for use with IO space
1298 * @dev: PCI device to be initialized
1299 *
1300 * Initialize device before it's used by a driver. Ask low-level code
1301 * to enable I/O resources. Wake up the device if it was suspended.
1302 * Beware, this function can fail.
1303 */
1304int pci_enable_device_io(struct pci_dev *dev)
1305{
1306 return pci_enable_device_flags(dev, IORESOURCE_IO);
1307}
1308
1309/**
1310 * pci_enable_device_mem - Initialize a device for use with Memory space
1311 * @dev: PCI device to be initialized
1312 *
1313 * Initialize device before it's used by a driver. Ask low-level code
1314 * to enable Memory resources. Wake up the device if it was suspended.
1315 * Beware, this function can fail.
1316 */
1317int pci_enable_device_mem(struct pci_dev *dev)
1318{
1319 return pci_enable_device_flags(dev, IORESOURCE_MEM);
1320}
1321
1322/**
1323 * pci_enable_device - Initialize device before it's used by a driver.
1324 * @dev: PCI device to be initialized
1325 *
1326 * Initialize device before it's used by a driver. Ask low-level code
1327 * to enable I/O and memory. Wake up the device if it was suspended.
1328 * Beware, this function can fail.
1329 *
1330 * Note we don't actually enable the device many times if we call
1331 * this function repeatedly (we just increment the count).
1332 */
1333int pci_enable_device(struct pci_dev *dev)
1334{
1335 return pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
1336}
1337
1338/*
1339 * Managed PCI resources. This manages device on/off, intx/msi/msix
1340 * on/off and BAR regions. pci_dev itself records msi/msix status, so
1341 * there's no need to track it separately. pci_devres is initialized
1342 * when a device is enabled using managed PCI device enable interface.
1343 */
1344struct pci_devres {
1345 unsigned int enabled:1;
1346 unsigned int pinned:1;
1347 unsigned int orig_intx:1;
1348 unsigned int restore_intx:1;
1349 u32 region_mask;
1350};
1351
1352static void pcim_release(struct device *gendev, void *res)
1353{
1354 struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
1355 struct pci_devres *this = res;
1356 int i;
1357
1358 if (dev->msi_enabled)
1359 pci_disable_msi(dev);
1360 if (dev->msix_enabled)
1361 pci_disable_msix(dev);
1362
1363 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1364 if (this->region_mask & (1 << i))
1365 pci_release_region(dev, i);
1366
1367 if (this->restore_intx)
1368 pci_intx(dev, this->orig_intx);
1369
1370 if (this->enabled && !this->pinned)
1371 pci_disable_device(dev);
1372}
1373
1374static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
1375{
1376 struct pci_devres *dr, *new_dr;
1377
1378 dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1379 if (dr)
1380 return dr;
1381
1382 new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1383 if (!new_dr)
1384 return NULL;
1385 return devres_get(&pdev->dev, new_dr, NULL, NULL);
1386}
1387
1388static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
1389{
1390 if (pci_is_managed(pdev))
1391 return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1392 return NULL;
1393}
1394
1395/**
1396 * pcim_enable_device - Managed pci_enable_device()
1397 * @pdev: PCI device to be initialized
1398 *
1399 * Managed pci_enable_device().
1400 */
1401int pcim_enable_device(struct pci_dev *pdev)
1402{
1403 struct pci_devres *dr;
1404 int rc;
1405
1406 dr = get_pci_dr(pdev);
1407 if (unlikely(!dr))
1408 return -ENOMEM;
1409 if (dr->enabled)
1410 return 0;
1411
1412 rc = pci_enable_device(pdev);
1413 if (!rc) {
1414 pdev->is_managed = 1;
1415 dr->enabled = 1;
1416 }
1417 return rc;
1418}
1419
1420/**
1421 * pcim_pin_device - Pin managed PCI device
1422 * @pdev: PCI device to pin
1423 *
1424 * Pin managed PCI device @pdev. Pinned device won't be disabled on
1425 * driver detach. @pdev must have been enabled with
1426 * pcim_enable_device().
1427 */
1428void pcim_pin_device(struct pci_dev *pdev)
1429{
1430 struct pci_devres *dr;
1431
1432 dr = find_pci_dr(pdev);
1433 WARN_ON(!dr || !dr->enabled);
1434 if (dr)
1435 dr->pinned = 1;
1436}
1437
1438/*
1439 * pcibios_add_device - provide arch specific hooks when adding device dev
1440 * @dev: the PCI device being added
1441 *
1442 * Permits the platform to provide architecture specific functionality when
1443 * devices are added. This is the default implementation. Architecture
1444 * implementations can override this.
1445 */
1446int __weak pcibios_add_device (struct pci_dev *dev)
1447{
1448 return 0;
1449}
1450
1451/**
1452 * pcibios_release_device - provide arch specific hooks when releasing device dev
1453 * @dev: the PCI device being released
1454 *
1455 * Permits the platform to provide architecture specific functionality when
1456 * devices are released. This is the default implementation. Architecture
1457 * implementations can override this.
1458 */
1459void __weak pcibios_release_device(struct pci_dev *dev) {}
1460
1461/**
1462 * pcibios_disable_device - disable arch specific PCI resources for device dev
1463 * @dev: the PCI device to disable
1464 *
1465 * Disables architecture specific PCI resources for the device. This
1466 * is the default implementation. Architecture implementations can
1467 * override this.
1468 */
1469void __weak pcibios_disable_device (struct pci_dev *dev) {}
1470
1471static void do_pci_disable_device(struct pci_dev *dev)
1472{
1473 u16 pci_command;
1474
1475 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1476 if (pci_command & PCI_COMMAND_MASTER) {
1477 pci_command &= ~PCI_COMMAND_MASTER;
1478 pci_write_config_word(dev, PCI_COMMAND, pci_command);
1479 }
1480
1481 pcibios_disable_device(dev);
1482}
1483
1484/**
1485 * pci_disable_enabled_device - Disable device without updating enable_cnt
1486 * @dev: PCI device to disable
1487 *
1488 * NOTE: This function is a backend of PCI power management routines and is
1489 * not supposed to be called drivers.
1490 */
1491void pci_disable_enabled_device(struct pci_dev *dev)
1492{
1493 if (pci_is_enabled(dev))
1494 do_pci_disable_device(dev);
1495}
1496
1497/**
1498 * pci_disable_device - Disable PCI device after use
1499 * @dev: PCI device to be disabled
1500 *
1501 * Signal to the system that the PCI device is not in use by the system
1502 * anymore. This only involves disabling PCI bus-mastering, if active.
1503 *
1504 * Note we don't actually disable the device until all callers of
1505 * pci_enable_device() have called pci_disable_device().
1506 */
1507void
1508pci_disable_device(struct pci_dev *dev)
1509{
1510 struct pci_devres *dr;
1511
1512 dr = find_pci_dr(dev);
1513 if (dr)
1514 dr->enabled = 0;
1515
1516 dev_WARN_ONCE(&dev->dev, atomic_read(&dev->enable_cnt) <= 0,
1517 "disabling already-disabled device");
1518
1519 if (atomic_dec_return(&dev->enable_cnt) != 0)
1520 return;
1521
1522 do_pci_disable_device(dev);
1523
1524 dev->is_busmaster = 0;
1525}
1526
1527/**
1528 * pcibios_set_pcie_reset_state - set reset state for device dev
1529 * @dev: the PCIe device reset
1530 * @state: Reset state to enter into
1531 *
1532 *
1533 * Sets the PCIe reset state for the device. This is the default
1534 * implementation. Architecture implementations can override this.
1535 */
1536int __weak pcibios_set_pcie_reset_state(struct pci_dev *dev,
1537 enum pcie_reset_state state)
1538{
1539 return -EINVAL;
1540}
1541
1542/**
1543 * pci_set_pcie_reset_state - set reset state for device dev
1544 * @dev: the PCIe device reset
1545 * @state: Reset state to enter into
1546 *
1547 *
1548 * Sets the PCI reset state for the device.
1549 */
1550int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1551{
1552 return pcibios_set_pcie_reset_state(dev, state);
1553}
1554
1555/**
1556 * pci_check_pme_status - Check if given device has generated PME.
1557 * @dev: Device to check.
1558 *
1559 * Check the PME status of the device and if set, clear it and clear PME enable
1560 * (if set). Return 'true' if PME status and PME enable were both set or
1561 * 'false' otherwise.
1562 */
1563bool pci_check_pme_status(struct pci_dev *dev)
1564{
1565 int pmcsr_pos;
1566 u16 pmcsr;
1567 bool ret = false;
1568
1569 if (!dev->pm_cap)
1570 return false;
1571
1572 pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
1573 pci_read_config_word(dev, pmcsr_pos, &pmcsr);
1574 if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
1575 return false;
1576
1577 /* Clear PME status. */
1578 pmcsr |= PCI_PM_CTRL_PME_STATUS;
1579 if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
1580 /* Disable PME to avoid interrupt flood. */
1581 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1582 ret = true;
1583 }
1584
1585 pci_write_config_word(dev, pmcsr_pos, pmcsr);
1586
1587 return ret;
1588}
1589
1590/**
1591 * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
1592 * @dev: Device to handle.
1593 * @pme_poll_reset: Whether or not to reset the device's pme_poll flag.
1594 *
1595 * Check if @dev has generated PME and queue a resume request for it in that
1596 * case.
1597 */
1598static int pci_pme_wakeup(struct pci_dev *dev, void *pme_poll_reset)
1599{
1600 if (pme_poll_reset && dev->pme_poll)
1601 dev->pme_poll = false;
1602
1603 if (pci_check_pme_status(dev)) {
1604 pci_wakeup_event(dev);
1605 pm_request_resume(&dev->dev);
1606 }
1607 return 0;
1608}
1609
1610/**
1611 * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
1612 * @bus: Top bus of the subtree to walk.
1613 */
1614void pci_pme_wakeup_bus(struct pci_bus *bus)
1615{
1616 if (bus)
1617 pci_walk_bus(bus, pci_pme_wakeup, (void *)true);
1618}
1619
1620
1621/**
1622 * pci_pme_capable - check the capability of PCI device to generate PME#
1623 * @dev: PCI device to handle.
1624 * @state: PCI state from which device will issue PME#.
1625 */
1626bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1627{
1628 if (!dev->pm_cap)
1629 return false;
1630
1631 return !!(dev->pme_support & (1 << state));
1632}
1633
1634static void pci_pme_list_scan(struct work_struct *work)
1635{
1636 struct pci_pme_device *pme_dev, *n;
1637
1638 mutex_lock(&pci_pme_list_mutex);
1639 list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) {
1640 if (pme_dev->dev->pme_poll) {
1641 struct pci_dev *bridge;
1642
1643 bridge = pme_dev->dev->bus->self;
1644 /*
1645 * If bridge is in low power state, the
1646 * configuration space of subordinate devices
1647 * may be not accessible
1648 */
1649 if (bridge && bridge->current_state != PCI_D0)
1650 continue;
1651 pci_pme_wakeup(pme_dev->dev, NULL);
1652 } else {
1653 list_del(&pme_dev->list);
1654 kfree(pme_dev);
1655 }
1656 }
1657 if (!list_empty(&pci_pme_list))
1658 schedule_delayed_work(&pci_pme_work,
1659 msecs_to_jiffies(PME_TIMEOUT));
1660 mutex_unlock(&pci_pme_list_mutex);
1661}
1662
1663/**
1664 * pci_pme_active - enable or disable PCI device's PME# function
1665 * @dev: PCI device to handle.
1666 * @enable: 'true' to enable PME# generation; 'false' to disable it.
1667 *
1668 * The caller must verify that the device is capable of generating PME# before
1669 * calling this function with @enable equal to 'true'.
1670 */
1671void pci_pme_active(struct pci_dev *dev, bool enable)
1672{
1673 u16 pmcsr;
1674
1675 if (!dev->pme_support)
1676 return;
1677
1678 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1679 /* Clear PME_Status by writing 1 to it and enable PME# */
1680 pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1681 if (!enable)
1682 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1683
1684 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1685
1686 /*
1687 * PCI (as opposed to PCIe) PME requires that the device have
1688 * its PME# line hooked up correctly. Not all hardware vendors
1689 * do this, so the PME never gets delivered and the device
1690 * remains asleep. The easiest way around this is to
1691 * periodically walk the list of suspended devices and check
1692 * whether any have their PME flag set. The assumption is that
1693 * we'll wake up often enough anyway that this won't be a huge
1694 * hit, and the power savings from the devices will still be a
1695 * win.
1696 *
1697 * Although PCIe uses in-band PME message instead of PME# line
1698 * to report PME, PME does not work for some PCIe devices in
1699 * reality. For example, there are devices that set their PME
1700 * status bits, but don't really bother to send a PME message;
1701 * there are PCI Express Root Ports that don't bother to
1702 * trigger interrupts when they receive PME messages from the
1703 * devices below. So PME poll is used for PCIe devices too.
1704 */
1705
1706 if (dev->pme_poll) {
1707 struct pci_pme_device *pme_dev;
1708 if (enable) {
1709 pme_dev = kmalloc(sizeof(struct pci_pme_device),
1710 GFP_KERNEL);
1711 if (!pme_dev) {
1712 dev_warn(&dev->dev, "can't enable PME#\n");
1713 return;
1714 }
1715 pme_dev->dev = dev;
1716 mutex_lock(&pci_pme_list_mutex);
1717 list_add(&pme_dev->list, &pci_pme_list);
1718 if (list_is_singular(&pci_pme_list))
1719 schedule_delayed_work(&pci_pme_work,
1720 msecs_to_jiffies(PME_TIMEOUT));
1721 mutex_unlock(&pci_pme_list_mutex);
1722 } else {
1723 mutex_lock(&pci_pme_list_mutex);
1724 list_for_each_entry(pme_dev, &pci_pme_list, list) {
1725 if (pme_dev->dev == dev) {
1726 list_del(&pme_dev->list);
1727 kfree(pme_dev);
1728 break;
1729 }
1730 }
1731 mutex_unlock(&pci_pme_list_mutex);
1732 }
1733 }
1734
1735 dev_dbg(&dev->dev, "PME# %s\n", enable ? "enabled" : "disabled");
1736}
1737
1738/**
1739 * __pci_enable_wake - enable PCI device as wakeup event source
1740 * @dev: PCI device affected
1741 * @state: PCI state from which device will issue wakeup events
1742 * @runtime: True if the events are to be generated at run time
1743 * @enable: True to enable event generation; false to disable
1744 *
1745 * This enables the device as a wakeup event source, or disables it.
1746 * When such events involves platform-specific hooks, those hooks are
1747 * called automatically by this routine.
1748 *
1749 * Devices with legacy power management (no standard PCI PM capabilities)
1750 * always require such platform hooks.
1751 *
1752 * RETURN VALUE:
1753 * 0 is returned on success
1754 * -EINVAL is returned if device is not supposed to wake up the system
1755 * Error code depending on the platform is returned if both the platform and
1756 * the native mechanism fail to enable the generation of wake-up events
1757 */
1758int __pci_enable_wake(struct pci_dev *dev, pci_power_t state,
1759 bool runtime, bool enable)
1760{
1761 int ret = 0;
1762
1763 if (enable && !runtime && !device_may_wakeup(&dev->dev))
1764 return -EINVAL;
1765
1766 /* Don't do the same thing twice in a row for one device. */
1767 if (!!enable == !!dev->wakeup_prepared)
1768 return 0;
1769
1770 /*
1771 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1772 * Anderson we should be doing PME# wake enable followed by ACPI wake
1773 * enable. To disable wake-up we call the platform first, for symmetry.
1774 */
1775
1776 if (enable) {
1777 int error;
1778
1779 if (pci_pme_capable(dev, state))
1780 pci_pme_active(dev, true);
1781 else
1782 ret = 1;
1783 error = runtime ? platform_pci_run_wake(dev, true) :
1784 platform_pci_sleep_wake(dev, true);
1785 if (ret)
1786 ret = error;
1787 if (!ret)
1788 dev->wakeup_prepared = true;
1789 } else {
1790 if (runtime)
1791 platform_pci_run_wake(dev, false);
1792 else
1793 platform_pci_sleep_wake(dev, false);
1794 pci_pme_active(dev, false);
1795 dev->wakeup_prepared = false;
1796 }
1797
1798 return ret;
1799}
1800EXPORT_SYMBOL(__pci_enable_wake);
1801
1802/**
1803 * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1804 * @dev: PCI device to prepare
1805 * @enable: True to enable wake-up event generation; false to disable
1806 *
1807 * Many drivers want the device to wake up the system from D3_hot or D3_cold
1808 * and this function allows them to set that up cleanly - pci_enable_wake()
1809 * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1810 * ordering constraints.
1811 *
1812 * This function only returns error code if the device is not capable of
1813 * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1814 * enable wake-up power for it.
1815 */
1816int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1817{
1818 return pci_pme_capable(dev, PCI_D3cold) ?
1819 pci_enable_wake(dev, PCI_D3cold, enable) :
1820 pci_enable_wake(dev, PCI_D3hot, enable);
1821}
1822
1823/**
1824 * pci_target_state - find an appropriate low power state for a given PCI dev
1825 * @dev: PCI device
1826 *
1827 * Use underlying platform code to find a supported low power state for @dev.
1828 * If the platform can't manage @dev, return the deepest state from which it
1829 * can generate wake events, based on any available PME info.
1830 */
1831static pci_power_t pci_target_state(struct pci_dev *dev)
1832{
1833 pci_power_t target_state = PCI_D3hot;
1834
1835 if (platform_pci_power_manageable(dev)) {
1836 /*
1837 * Call the platform to choose the target state of the device
1838 * and enable wake-up from this state if supported.
1839 */
1840 pci_power_t state = platform_pci_choose_state(dev);
1841
1842 switch (state) {
1843 case PCI_POWER_ERROR:
1844 case PCI_UNKNOWN:
1845 break;
1846 case PCI_D1:
1847 case PCI_D2:
1848 if (pci_no_d1d2(dev))
1849 break;
1850 default:
1851 target_state = state;
1852 }
1853 } else if (!dev->pm_cap) {
1854 target_state = PCI_D0;
1855 } else if (device_may_wakeup(&dev->dev)) {
1856 /*
1857 * Find the deepest state from which the device can generate
1858 * wake-up events, make it the target state and enable device
1859 * to generate PME#.
1860 */
1861 if (dev->pme_support) {
1862 while (target_state
1863 && !(dev->pme_support & (1 << target_state)))
1864 target_state--;
1865 }
1866 }
1867
1868 return target_state;
1869}
1870
1871/**
1872 * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1873 * @dev: Device to handle.
1874 *
1875 * Choose the power state appropriate for the device depending on whether
1876 * it can wake up the system and/or is power manageable by the platform
1877 * (PCI_D3hot is the default) and put the device into that state.
1878 */
1879int pci_prepare_to_sleep(struct pci_dev *dev)
1880{
1881 pci_power_t target_state = pci_target_state(dev);
1882 int error;
1883
1884 if (target_state == PCI_POWER_ERROR)
1885 return -EIO;
1886
1887 /* D3cold during system suspend/hibernate is not supported */
1888 if (target_state > PCI_D3hot)
1889 target_state = PCI_D3hot;
1890
1891 pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
1892
1893 error = pci_set_power_state(dev, target_state);
1894
1895 if (error)
1896 pci_enable_wake(dev, target_state, false);
1897
1898 return error;
1899}
1900
1901/**
1902 * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1903 * @dev: Device to handle.
1904 *
1905 * Disable device's system wake-up capability and put it into D0.
1906 */
1907int pci_back_from_sleep(struct pci_dev *dev)
1908{
1909 pci_enable_wake(dev, PCI_D0, false);
1910 return pci_set_power_state(dev, PCI_D0);
1911}
1912
1913/**
1914 * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend.
1915 * @dev: PCI device being suspended.
1916 *
1917 * Prepare @dev to generate wake-up events at run time and put it into a low
1918 * power state.
1919 */
1920int pci_finish_runtime_suspend(struct pci_dev *dev)
1921{
1922 pci_power_t target_state = pci_target_state(dev);
1923 int error;
1924
1925 if (target_state == PCI_POWER_ERROR)
1926 return -EIO;
1927
1928 dev->runtime_d3cold = target_state == PCI_D3cold;
1929
1930 __pci_enable_wake(dev, target_state, true, pci_dev_run_wake(dev));
1931
1932 error = pci_set_power_state(dev, target_state);
1933
1934 if (error) {
1935 __pci_enable_wake(dev, target_state, true, false);
1936 dev->runtime_d3cold = false;
1937 }
1938
1939 return error;
1940}
1941
1942/**
1943 * pci_dev_run_wake - Check if device can generate run-time wake-up events.
1944 * @dev: Device to check.
1945 *
1946 * Return true if the device itself is capable of generating wake-up events
1947 * (through the platform or using the native PCIe PME) or if the device supports
1948 * PME and one of its upstream bridges can generate wake-up events.
1949 */
1950bool pci_dev_run_wake(struct pci_dev *dev)
1951{
1952 struct pci_bus *bus = dev->bus;
1953
1954 if (device_run_wake(&dev->dev))
1955 return true;
1956
1957 if (!dev->pme_support)
1958 return false;
1959
1960 while (bus->parent) {
1961 struct pci_dev *bridge = bus->self;
1962
1963 if (device_run_wake(&bridge->dev))
1964 return true;
1965
1966 bus = bus->parent;
1967 }
1968
1969 /* We have reached the root bus. */
1970 if (bus->bridge)
1971 return device_run_wake(bus->bridge);
1972
1973 return false;
1974}
1975EXPORT_SYMBOL_GPL(pci_dev_run_wake);
1976
1977void pci_config_pm_runtime_get(struct pci_dev *pdev)
1978{
1979 struct device *dev = &pdev->dev;
1980 struct device *parent = dev->parent;
1981
1982 if (parent)
1983 pm_runtime_get_sync(parent);
1984 pm_runtime_get_noresume(dev);
1985 /*
1986 * pdev->current_state is set to PCI_D3cold during suspending,
1987 * so wait until suspending completes
1988 */
1989 pm_runtime_barrier(dev);
1990 /*
1991 * Only need to resume devices in D3cold, because config
1992 * registers are still accessible for devices suspended but
1993 * not in D3cold.
1994 */
1995 if (pdev->current_state == PCI_D3cold)
1996 pm_runtime_resume(dev);
1997}
1998
1999void pci_config_pm_runtime_put(struct pci_dev *pdev)
2000{
2001 struct device *dev = &pdev->dev;
2002 struct device *parent = dev->parent;
2003
2004 pm_runtime_put(dev);
2005 if (parent)
2006 pm_runtime_put_sync(parent);
2007}
2008
2009/**
2010 * pci_pm_init - Initialize PM functions of given PCI device
2011 * @dev: PCI device to handle.
2012 */
2013void pci_pm_init(struct pci_dev *dev)
2014{
2015 int pm;
2016 u16 pmc;
2017
2018 pm_runtime_forbid(&dev->dev);
2019 pm_runtime_set_active(&dev->dev);
2020 pm_runtime_enable(&dev->dev);
2021 device_enable_async_suspend(&dev->dev);
2022 dev->wakeup_prepared = false;
2023
2024 dev->pm_cap = 0;
2025 dev->pme_support = 0;
2026
2027 /* find PCI PM capability in list */
2028 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
2029 if (!pm)
2030 return;
2031 /* Check device's ability to generate PME# */
2032 pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
2033
2034 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
2035 dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
2036 pmc & PCI_PM_CAP_VER_MASK);
2037 return;
2038 }
2039
2040 dev->pm_cap = pm;
2041 dev->d3_delay = PCI_PM_D3_WAIT;
2042 dev->d3cold_delay = PCI_PM_D3COLD_WAIT;
2043 dev->d3cold_allowed = true;
2044
2045 dev->d1_support = false;
2046 dev->d2_support = false;
2047 if (!pci_no_d1d2(dev)) {
2048 if (pmc & PCI_PM_CAP_D1)
2049 dev->d1_support = true;
2050 if (pmc & PCI_PM_CAP_D2)
2051 dev->d2_support = true;
2052
2053 if (dev->d1_support || dev->d2_support)
2054 dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
2055 dev->d1_support ? " D1" : "",
2056 dev->d2_support ? " D2" : "");
2057 }
2058
2059 pmc &= PCI_PM_CAP_PME_MASK;
2060 if (pmc) {
2061 dev_printk(KERN_DEBUG, &dev->dev,
2062 "PME# supported from%s%s%s%s%s\n",
2063 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
2064 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
2065 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
2066 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
2067 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
2068 dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
2069 dev->pme_poll = true;
2070 /*
2071 * Make device's PM flags reflect the wake-up capability, but
2072 * let the user space enable it to wake up the system as needed.
2073 */
2074 device_set_wakeup_capable(&dev->dev, true);
2075 /* Disable the PME# generation functionality */
2076 pci_pme_active(dev, false);
2077 }
2078}
2079
2080static void pci_add_saved_cap(struct pci_dev *pci_dev,
2081 struct pci_cap_saved_state *new_cap)
2082{
2083 hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space);
2084}
2085
2086/**
2087 * _pci_add_cap_save_buffer - allocate buffer for saving given
2088 * capability registers
2089 * @dev: the PCI device
2090 * @cap: the capability to allocate the buffer for
2091 * @extended: Standard or Extended capability ID
2092 * @size: requested size of the buffer
2093 */
2094static int _pci_add_cap_save_buffer(struct pci_dev *dev, u16 cap,
2095 bool extended, unsigned int size)
2096{
2097 int pos;
2098 struct pci_cap_saved_state *save_state;
2099
2100 if (extended)
2101 pos = pci_find_ext_capability(dev, cap);
2102 else
2103 pos = pci_find_capability(dev, cap);
2104
2105 if (pos <= 0)
2106 return 0;
2107
2108 save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
2109 if (!save_state)
2110 return -ENOMEM;
2111
2112 save_state->cap.cap_nr = cap;
2113 save_state->cap.cap_extended = extended;
2114 save_state->cap.size = size;
2115 pci_add_saved_cap(dev, save_state);
2116
2117 return 0;
2118}
2119
2120int pci_add_cap_save_buffer(struct pci_dev *dev, char cap, unsigned int size)
2121{
2122 return _pci_add_cap_save_buffer(dev, cap, false, size);
2123}
2124
2125int pci_add_ext_cap_save_buffer(struct pci_dev *dev, u16 cap, unsigned int size)
2126{
2127 return _pci_add_cap_save_buffer(dev, cap, true, size);
2128}
2129
2130/**
2131 * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
2132 * @dev: the PCI device
2133 */
2134void pci_allocate_cap_save_buffers(struct pci_dev *dev)
2135{
2136 int error;
2137
2138 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
2139 PCI_EXP_SAVE_REGS * sizeof(u16));
2140 if (error)
2141 dev_err(&dev->dev,
2142 "unable to preallocate PCI Express save buffer\n");
2143
2144 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
2145 if (error)
2146 dev_err(&dev->dev,
2147 "unable to preallocate PCI-X save buffer\n");
2148
2149 pci_allocate_vc_save_buffers(dev);
2150}
2151
2152void pci_free_cap_save_buffers(struct pci_dev *dev)
2153{
2154 struct pci_cap_saved_state *tmp;
2155 struct hlist_node *n;
2156
2157 hlist_for_each_entry_safe(tmp, n, &dev->saved_cap_space, next)
2158 kfree(tmp);
2159}
2160
2161/**
2162 * pci_configure_ari - enable or disable ARI forwarding
2163 * @dev: the PCI device
2164 *
2165 * If @dev and its upstream bridge both support ARI, enable ARI in the
2166 * bridge. Otherwise, disable ARI in the bridge.
2167 */
2168void pci_configure_ari(struct pci_dev *dev)
2169{
2170 u32 cap;
2171 struct pci_dev *bridge;
2172
2173 if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn)
2174 return;
2175
2176 bridge = dev->bus->self;
2177 if (!bridge)
2178 return;
2179
2180 pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap);
2181 if (!(cap & PCI_EXP_DEVCAP2_ARI))
2182 return;
2183
2184 if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) {
2185 pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2,
2186 PCI_EXP_DEVCTL2_ARI);
2187 bridge->ari_enabled = 1;
2188 } else {
2189 pcie_capability_clear_word(bridge, PCI_EXP_DEVCTL2,
2190 PCI_EXP_DEVCTL2_ARI);
2191 bridge->ari_enabled = 0;
2192 }
2193}
2194
2195static int pci_acs_enable;
2196
2197/**
2198 * pci_request_acs - ask for ACS to be enabled if supported
2199 */
2200void pci_request_acs(void)
2201{
2202 pci_acs_enable = 1;
2203}
2204
2205/**
2206 * pci_std_enable_acs - enable ACS on devices using standard ACS capabilites
2207 * @dev: the PCI device
2208 */
2209static int pci_std_enable_acs(struct pci_dev *dev)
2210{
2211 int pos;
2212 u16 cap;
2213 u16 ctrl;
2214
2215 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
2216 if (!pos)
2217 return -ENODEV;
2218
2219 pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
2220 pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
2221
2222 /* Source Validation */
2223 ctrl |= (cap & PCI_ACS_SV);
2224
2225 /* P2P Request Redirect */
2226 ctrl |= (cap & PCI_ACS_RR);
2227
2228 /* P2P Completion Redirect */
2229 ctrl |= (cap & PCI_ACS_CR);
2230
2231 /* Upstream Forwarding */
2232 ctrl |= (cap & PCI_ACS_UF);
2233
2234 pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
2235
2236 return 0;
2237}
2238
2239/**
2240 * pci_enable_acs - enable ACS if hardware support it
2241 * @dev: the PCI device
2242 */
2243void pci_enable_acs(struct pci_dev *dev)
2244{
2245 if (!pci_acs_enable)
2246 return;
2247
2248 if (!pci_std_enable_acs(dev))
2249 return;
2250
2251 pci_dev_specific_enable_acs(dev);
2252}
2253
2254static bool pci_acs_flags_enabled(struct pci_dev *pdev, u16 acs_flags)
2255{
2256 int pos;
2257 u16 cap, ctrl;
2258
2259 pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ACS);
2260 if (!pos)
2261 return false;
2262
2263 /*
2264 * Except for egress control, capabilities are either required
2265 * or only required if controllable. Features missing from the
2266 * capability field can therefore be assumed as hard-wired enabled.
2267 */
2268 pci_read_config_word(pdev, pos + PCI_ACS_CAP, &cap);
2269 acs_flags &= (cap | PCI_ACS_EC);
2270
2271 pci_read_config_word(pdev, pos + PCI_ACS_CTRL, &ctrl);
2272 return (ctrl & acs_flags) == acs_flags;
2273}
2274
2275/**
2276 * pci_acs_enabled - test ACS against required flags for a given device
2277 * @pdev: device to test
2278 * @acs_flags: required PCI ACS flags
2279 *
2280 * Return true if the device supports the provided flags. Automatically
2281 * filters out flags that are not implemented on multifunction devices.
2282 *
2283 * Note that this interface checks the effective ACS capabilities of the
2284 * device rather than the actual capabilities. For instance, most single
2285 * function endpoints are not required to support ACS because they have no
2286 * opportunity for peer-to-peer access. We therefore return 'true'
2287 * regardless of whether the device exposes an ACS capability. This makes
2288 * it much easier for callers of this function to ignore the actual type
2289 * or topology of the device when testing ACS support.
2290 */
2291bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags)
2292{
2293 int ret;
2294
2295 ret = pci_dev_specific_acs_enabled(pdev, acs_flags);
2296 if (ret >= 0)
2297 return ret > 0;
2298
2299 /*
2300 * Conventional PCI and PCI-X devices never support ACS, either
2301 * effectively or actually. The shared bus topology implies that
2302 * any device on the bus can receive or snoop DMA.
2303 */
2304 if (!pci_is_pcie(pdev))
2305 return false;
2306
2307 switch (pci_pcie_type(pdev)) {
2308 /*
2309 * PCI/X-to-PCIe bridges are not specifically mentioned by the spec,
2310 * but since their primary interface is PCI/X, we conservatively
2311 * handle them as we would a non-PCIe device.
2312 */
2313 case PCI_EXP_TYPE_PCIE_BRIDGE:
2314 /*
2315 * PCIe 3.0, 6.12.1 excludes ACS on these devices. "ACS is never
2316 * applicable... must never implement an ACS Extended Capability...".
2317 * This seems arbitrary, but we take a conservative interpretation
2318 * of this statement.
2319 */
2320 case PCI_EXP_TYPE_PCI_BRIDGE:
2321 case PCI_EXP_TYPE_RC_EC:
2322 return false;
2323 /*
2324 * PCIe 3.0, 6.12.1.1 specifies that downstream and root ports should
2325 * implement ACS in order to indicate their peer-to-peer capabilities,
2326 * regardless of whether they are single- or multi-function devices.
2327 */
2328 case PCI_EXP_TYPE_DOWNSTREAM:
2329 case PCI_EXP_TYPE_ROOT_PORT:
2330 return pci_acs_flags_enabled(pdev, acs_flags);
2331 /*
2332 * PCIe 3.0, 6.12.1.2 specifies ACS capabilities that should be
2333 * implemented by the remaining PCIe types to indicate peer-to-peer
2334 * capabilities, but only when they are part of a multifunction
2335 * device. The footnote for section 6.12 indicates the specific
2336 * PCIe types included here.
2337 */
2338 case PCI_EXP_TYPE_ENDPOINT:
2339 case PCI_EXP_TYPE_UPSTREAM:
2340 case PCI_EXP_TYPE_LEG_END:
2341 case PCI_EXP_TYPE_RC_END:
2342 if (!pdev->multifunction)
2343 break;
2344
2345 return pci_acs_flags_enabled(pdev, acs_flags);
2346 }
2347
2348 /*
2349 * PCIe 3.0, 6.12.1.3 specifies no ACS capabilities are applicable
2350 * to single function devices with the exception of downstream ports.
2351 */
2352 return true;
2353}
2354
2355/**
2356 * pci_acs_path_enable - test ACS flags from start to end in a hierarchy
2357 * @start: starting downstream device
2358 * @end: ending upstream device or NULL to search to the root bus
2359 * @acs_flags: required flags
2360 *
2361 * Walk up a device tree from start to end testing PCI ACS support. If
2362 * any step along the way does not support the required flags, return false.
2363 */
2364bool pci_acs_path_enabled(struct pci_dev *start,
2365 struct pci_dev *end, u16 acs_flags)
2366{
2367 struct pci_dev *pdev, *parent = start;
2368
2369 do {
2370 pdev = parent;
2371
2372 if (!pci_acs_enabled(pdev, acs_flags))
2373 return false;
2374
2375 if (pci_is_root_bus(pdev->bus))
2376 return (end == NULL);
2377
2378 parent = pdev->bus->self;
2379 } while (pdev != end);
2380
2381 return true;
2382}
2383
2384/**
2385 * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
2386 * @dev: the PCI device
2387 * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTC, 4=INTD)
2388 *
2389 * Perform INTx swizzling for a device behind one level of bridge. This is
2390 * required by section 9.1 of the PCI-to-PCI bridge specification for devices
2391 * behind bridges on add-in cards. For devices with ARI enabled, the slot
2392 * number is always 0 (see the Implementation Note in section 2.2.8.1 of
2393 * the PCI Express Base Specification, Revision 2.1)
2394 */
2395u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin)
2396{
2397 int slot;
2398
2399 if (pci_ari_enabled(dev->bus))
2400 slot = 0;
2401 else
2402 slot = PCI_SLOT(dev->devfn);
2403
2404 return (((pin - 1) + slot) % 4) + 1;
2405}
2406
2407int
2408pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
2409{
2410 u8 pin;
2411
2412 pin = dev->pin;
2413 if (!pin)
2414 return -1;
2415
2416 while (!pci_is_root_bus(dev->bus)) {
2417 pin = pci_swizzle_interrupt_pin(dev, pin);
2418 dev = dev->bus->self;
2419 }
2420 *bridge = dev;
2421 return pin;
2422}
2423
2424/**
2425 * pci_common_swizzle - swizzle INTx all the way to root bridge
2426 * @dev: the PCI device
2427 * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
2428 *
2429 * Perform INTx swizzling for a device. This traverses through all PCI-to-PCI
2430 * bridges all the way up to a PCI root bus.
2431 */
2432u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
2433{
2434 u8 pin = *pinp;
2435
2436 while (!pci_is_root_bus(dev->bus)) {
2437 pin = pci_swizzle_interrupt_pin(dev, pin);
2438 dev = dev->bus->self;
2439 }
2440 *pinp = pin;
2441 return PCI_SLOT(dev->devfn);
2442}
2443
2444/**
2445 * pci_release_region - Release a PCI bar
2446 * @pdev: PCI device whose resources were previously reserved by pci_request_region
2447 * @bar: BAR to release
2448 *
2449 * Releases the PCI I/O and memory resources previously reserved by a
2450 * successful call to pci_request_region. Call this function only
2451 * after all use of the PCI regions has ceased.
2452 */
2453void pci_release_region(struct pci_dev *pdev, int bar)
2454{
2455 struct pci_devres *dr;
2456
2457 if (pci_resource_len(pdev, bar) == 0)
2458 return;
2459 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
2460 release_region(pci_resource_start(pdev, bar),
2461 pci_resource_len(pdev, bar));
2462 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
2463 release_mem_region(pci_resource_start(pdev, bar),
2464 pci_resource_len(pdev, bar));
2465
2466 dr = find_pci_dr(pdev);
2467 if (dr)
2468 dr->region_mask &= ~(1 << bar);
2469}
2470
2471/**
2472 * __pci_request_region - Reserved PCI I/O and memory resource
2473 * @pdev: PCI device whose resources are to be reserved
2474 * @bar: BAR to be reserved
2475 * @res_name: Name to be associated with resource.
2476 * @exclusive: whether the region access is exclusive or not
2477 *
2478 * Mark the PCI region associated with PCI device @pdev BR @bar as
2479 * being reserved by owner @res_name. Do not access any
2480 * address inside the PCI regions unless this call returns
2481 * successfully.
2482 *
2483 * If @exclusive is set, then the region is marked so that userspace
2484 * is explicitly not allowed to map the resource via /dev/mem or
2485 * sysfs MMIO access.
2486 *
2487 * Returns 0 on success, or %EBUSY on error. A warning
2488 * message is also printed on failure.
2489 */
2490static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
2491 int exclusive)
2492{
2493 struct pci_devres *dr;
2494
2495 if (pci_resource_len(pdev, bar) == 0)
2496 return 0;
2497
2498 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
2499 if (!request_region(pci_resource_start(pdev, bar),
2500 pci_resource_len(pdev, bar), res_name))
2501 goto err_out;
2502 }
2503 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
2504 if (!__request_mem_region(pci_resource_start(pdev, bar),
2505 pci_resource_len(pdev, bar), res_name,
2506 exclusive))
2507 goto err_out;
2508 }
2509
2510 dr = find_pci_dr(pdev);
2511 if (dr)
2512 dr->region_mask |= 1 << bar;
2513
2514 return 0;
2515
2516err_out:
2517 dev_warn(&pdev->dev, "BAR %d: can't reserve %pR\n", bar,
2518 &pdev->resource[bar]);
2519 return -EBUSY;
2520}
2521
2522/**
2523 * pci_request_region - Reserve PCI I/O and memory resource
2524 * @pdev: PCI device whose resources are to be reserved
2525 * @bar: BAR to be reserved
2526 * @res_name: Name to be associated with resource
2527 *
2528 * Mark the PCI region associated with PCI device @pdev BAR @bar as
2529 * being reserved by owner @res_name. Do not access any
2530 * address inside the PCI regions unless this call returns
2531 * successfully.
2532 *
2533 * Returns 0 on success, or %EBUSY on error. A warning
2534 * message is also printed on failure.
2535 */
2536int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
2537{
2538 return __pci_request_region(pdev, bar, res_name, 0);
2539}
2540
2541/**
2542 * pci_request_region_exclusive - Reserved PCI I/O and memory resource
2543 * @pdev: PCI device whose resources are to be reserved
2544 * @bar: BAR to be reserved
2545 * @res_name: Name to be associated with resource.
2546 *
2547 * Mark the PCI region associated with PCI device @pdev BR @bar as
2548 * being reserved by owner @res_name. Do not access any
2549 * address inside the PCI regions unless this call returns
2550 * successfully.
2551 *
2552 * Returns 0 on success, or %EBUSY on error. A warning
2553 * message is also printed on failure.
2554 *
2555 * The key difference that _exclusive makes it that userspace is
2556 * explicitly not allowed to map the resource via /dev/mem or
2557 * sysfs.
2558 */
2559int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name)
2560{
2561 return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
2562}
2563/**
2564 * pci_release_selected_regions - Release selected PCI I/O and memory resources
2565 * @pdev: PCI device whose resources were previously reserved
2566 * @bars: Bitmask of BARs to be released
2567 *
2568 * Release selected PCI I/O and memory resources previously reserved.
2569 * Call this function only after all use of the PCI regions has ceased.
2570 */
2571void pci_release_selected_regions(struct pci_dev *pdev, int bars)
2572{
2573 int i;
2574
2575 for (i = 0; i < 6; i++)
2576 if (bars & (1 << i))
2577 pci_release_region(pdev, i);
2578}
2579
2580static int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
2581 const char *res_name, int excl)
2582{
2583 int i;
2584
2585 for (i = 0; i < 6; i++)
2586 if (bars & (1 << i))
2587 if (__pci_request_region(pdev, i, res_name, excl))
2588 goto err_out;
2589 return 0;
2590
2591err_out:
2592 while(--i >= 0)
2593 if (bars & (1 << i))
2594 pci_release_region(pdev, i);
2595
2596 return -EBUSY;
2597}
2598
2599
2600/**
2601 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
2602 * @pdev: PCI device whose resources are to be reserved
2603 * @bars: Bitmask of BARs to be requested
2604 * @res_name: Name to be associated with resource
2605 */
2606int pci_request_selected_regions(struct pci_dev *pdev, int bars,
2607 const char *res_name)
2608{
2609 return __pci_request_selected_regions(pdev, bars, res_name, 0);
2610}
2611
2612int pci_request_selected_regions_exclusive(struct pci_dev *pdev,
2613 int bars, const char *res_name)
2614{
2615 return __pci_request_selected_regions(pdev, bars, res_name,
2616 IORESOURCE_EXCLUSIVE);
2617}
2618
2619/**
2620 * pci_release_regions - Release reserved PCI I/O and memory resources
2621 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
2622 *
2623 * Releases all PCI I/O and memory resources previously reserved by a
2624 * successful call to pci_request_regions. Call this function only
2625 * after all use of the PCI regions has ceased.
2626 */
2627
2628void pci_release_regions(struct pci_dev *pdev)
2629{
2630 pci_release_selected_regions(pdev, (1 << 6) - 1);
2631}
2632
2633/**
2634 * pci_request_regions - Reserved PCI I/O and memory resources
2635 * @pdev: PCI device whose resources are to be reserved
2636 * @res_name: Name to be associated with resource.
2637 *
2638 * Mark all PCI regions associated with PCI device @pdev as
2639 * being reserved by owner @res_name. Do not access any
2640 * address inside the PCI regions unless this call returns
2641 * successfully.
2642 *
2643 * Returns 0 on success, or %EBUSY on error. A warning
2644 * message is also printed on failure.
2645 */
2646int pci_request_regions(struct pci_dev *pdev, const char *res_name)
2647{
2648 return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
2649}
2650
2651/**
2652 * pci_request_regions_exclusive - Reserved PCI I/O and memory resources
2653 * @pdev: PCI device whose resources are to be reserved
2654 * @res_name: Name to be associated with resource.
2655 *
2656 * Mark all PCI regions associated with PCI device @pdev as
2657 * being reserved by owner @res_name. Do not access any
2658 * address inside the PCI regions unless this call returns
2659 * successfully.
2660 *
2661 * pci_request_regions_exclusive() will mark the region so that
2662 * /dev/mem and the sysfs MMIO access will not be allowed.
2663 *
2664 * Returns 0 on success, or %EBUSY on error. A warning
2665 * message is also printed on failure.
2666 */
2667int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
2668{
2669 return pci_request_selected_regions_exclusive(pdev,
2670 ((1 << 6) - 1), res_name);
2671}
2672
2673static void __pci_set_master(struct pci_dev *dev, bool enable)
2674{
2675 u16 old_cmd, cmd;
2676
2677 pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
2678 if (enable)
2679 cmd = old_cmd | PCI_COMMAND_MASTER;
2680 else
2681 cmd = old_cmd & ~PCI_COMMAND_MASTER;
2682 if (cmd != old_cmd) {
2683 dev_dbg(&dev->dev, "%s bus mastering\n",
2684 enable ? "enabling" : "disabling");
2685 pci_write_config_word(dev, PCI_COMMAND, cmd);
2686 }
2687 dev->is_busmaster = enable;
2688}
2689
2690/**
2691 * pcibios_setup - process "pci=" kernel boot arguments
2692 * @str: string used to pass in "pci=" kernel boot arguments
2693 *
2694 * Process kernel boot arguments. This is the default implementation.
2695 * Architecture specific implementations can override this as necessary.
2696 */
2697char * __weak __init pcibios_setup(char *str)
2698{
2699 return str;
2700}
2701
2702/**
2703 * pcibios_set_master - enable PCI bus-mastering for device dev
2704 * @dev: the PCI device to enable
2705 *
2706 * Enables PCI bus-mastering for the device. This is the default
2707 * implementation. Architecture specific implementations can override
2708 * this if necessary.
2709 */
2710void __weak pcibios_set_master(struct pci_dev *dev)
2711{
2712 u8 lat;
2713
2714 /* The latency timer doesn't apply to PCIe (either Type 0 or Type 1) */
2715 if (pci_is_pcie(dev))
2716 return;
2717
2718 pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
2719 if (lat < 16)
2720 lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
2721 else if (lat > pcibios_max_latency)
2722 lat = pcibios_max_latency;
2723 else
2724 return;
2725
2726 pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
2727}
2728
2729/**
2730 * pci_set_master - enables bus-mastering for device dev
2731 * @dev: the PCI device to enable
2732 *
2733 * Enables bus-mastering on the device and calls pcibios_set_master()
2734 * to do the needed arch specific settings.
2735 */
2736void pci_set_master(struct pci_dev *dev)
2737{
2738 __pci_set_master(dev, true);
2739 pcibios_set_master(dev);
2740}
2741
2742/**
2743 * pci_clear_master - disables bus-mastering for device dev
2744 * @dev: the PCI device to disable
2745 */
2746void pci_clear_master(struct pci_dev *dev)
2747{
2748 __pci_set_master(dev, false);
2749}
2750
2751/**
2752 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
2753 * @dev: the PCI device for which MWI is to be enabled
2754 *
2755 * Helper function for pci_set_mwi.
2756 * Originally copied from drivers/net/acenic.c.
2757 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
2758 *
2759 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2760 */
2761int pci_set_cacheline_size(struct pci_dev *dev)
2762{
2763 u8 cacheline_size;
2764
2765 if (!pci_cache_line_size)
2766 return -EINVAL;
2767
2768 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
2769 equal to or multiple of the right value. */
2770 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2771 if (cacheline_size >= pci_cache_line_size &&
2772 (cacheline_size % pci_cache_line_size) == 0)
2773 return 0;
2774
2775 /* Write the correct value. */
2776 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
2777 /* Read it back. */
2778 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2779 if (cacheline_size == pci_cache_line_size)
2780 return 0;
2781
2782 dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
2783 "supported\n", pci_cache_line_size << 2);
2784
2785 return -EINVAL;
2786}
2787EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
2788
2789#ifdef PCI_DISABLE_MWI
2790int pci_set_mwi(struct pci_dev *dev)
2791{
2792 return 0;
2793}
2794
2795int pci_try_set_mwi(struct pci_dev *dev)
2796{
2797 return 0;
2798}
2799
2800void pci_clear_mwi(struct pci_dev *dev)
2801{
2802}
2803
2804#else
2805
2806/**
2807 * pci_set_mwi - enables memory-write-invalidate PCI transaction
2808 * @dev: the PCI device for which MWI is enabled
2809 *
2810 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2811 *
2812 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2813 */
2814int
2815pci_set_mwi(struct pci_dev *dev)
2816{
2817 int rc;
2818 u16 cmd;
2819
2820 rc = pci_set_cacheline_size(dev);
2821 if (rc)
2822 return rc;
2823
2824 pci_read_config_word(dev, PCI_COMMAND, &cmd);
2825 if (! (cmd & PCI_COMMAND_INVALIDATE)) {
2826 dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
2827 cmd |= PCI_COMMAND_INVALIDATE;
2828 pci_write_config_word(dev, PCI_COMMAND, cmd);
2829 }
2830
2831 return 0;
2832}
2833
2834/**
2835 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
2836 * @dev: the PCI device for which MWI is enabled
2837 *
2838 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2839 * Callers are not required to check the return value.
2840 *
2841 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2842 */
2843int pci_try_set_mwi(struct pci_dev *dev)
2844{
2845 int rc = pci_set_mwi(dev);
2846 return rc;
2847}
2848
2849/**
2850 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
2851 * @dev: the PCI device to disable
2852 *
2853 * Disables PCI Memory-Write-Invalidate transaction on the device
2854 */
2855void
2856pci_clear_mwi(struct pci_dev *dev)
2857{
2858 u16 cmd;
2859
2860 pci_read_config_word(dev, PCI_COMMAND, &cmd);
2861 if (cmd & PCI_COMMAND_INVALIDATE) {
2862 cmd &= ~PCI_COMMAND_INVALIDATE;
2863 pci_write_config_word(dev, PCI_COMMAND, cmd);
2864 }
2865}
2866#endif /* ! PCI_DISABLE_MWI */
2867
2868/**
2869 * pci_intx - enables/disables PCI INTx for device dev
2870 * @pdev: the PCI device to operate on
2871 * @enable: boolean: whether to enable or disable PCI INTx
2872 *
2873 * Enables/disables PCI INTx for device dev
2874 */
2875void
2876pci_intx(struct pci_dev *pdev, int enable)
2877{
2878 u16 pci_command, new;
2879
2880 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
2881
2882 if (enable) {
2883 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
2884 } else {
2885 new = pci_command | PCI_COMMAND_INTX_DISABLE;
2886 }
2887
2888 if (new != pci_command) {
2889 struct pci_devres *dr;
2890
2891 pci_write_config_word(pdev, PCI_COMMAND, new);
2892
2893 dr = find_pci_dr(pdev);
2894 if (dr && !dr->restore_intx) {
2895 dr->restore_intx = 1;
2896 dr->orig_intx = !enable;
2897 }
2898 }
2899}
2900
2901/**
2902 * pci_intx_mask_supported - probe for INTx masking support
2903 * @dev: the PCI device to operate on
2904 *
2905 * Check if the device dev support INTx masking via the config space
2906 * command word.
2907 */
2908bool pci_intx_mask_supported(struct pci_dev *dev)
2909{
2910 bool mask_supported = false;
2911 u16 orig, new;
2912
2913 if (dev->broken_intx_masking)
2914 return false;
2915
2916 pci_cfg_access_lock(dev);
2917
2918 pci_read_config_word(dev, PCI_COMMAND, &orig);
2919 pci_write_config_word(dev, PCI_COMMAND,
2920 orig ^ PCI_COMMAND_INTX_DISABLE);
2921 pci_read_config_word(dev, PCI_COMMAND, &new);
2922
2923 /*
2924 * There's no way to protect against hardware bugs or detect them
2925 * reliably, but as long as we know what the value should be, let's
2926 * go ahead and check it.
2927 */
2928 if ((new ^ orig) & ~PCI_COMMAND_INTX_DISABLE) {
2929 dev_err(&dev->dev, "Command register changed from "
2930 "0x%x to 0x%x: driver or hardware bug?\n", orig, new);
2931 } else if ((new ^ orig) & PCI_COMMAND_INTX_DISABLE) {
2932 mask_supported = true;
2933 pci_write_config_word(dev, PCI_COMMAND, orig);
2934 }
2935
2936 pci_cfg_access_unlock(dev);
2937 return mask_supported;
2938}
2939EXPORT_SYMBOL_GPL(pci_intx_mask_supported);
2940
2941static bool pci_check_and_set_intx_mask(struct pci_dev *dev, bool mask)
2942{
2943 struct pci_bus *bus = dev->bus;
2944 bool mask_updated = true;
2945 u32 cmd_status_dword;
2946 u16 origcmd, newcmd;
2947 unsigned long flags;
2948 bool irq_pending;
2949
2950 /*
2951 * We do a single dword read to retrieve both command and status.
2952 * Document assumptions that make this possible.
2953 */
2954 BUILD_BUG_ON(PCI_COMMAND % 4);
2955 BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
2956
2957 raw_spin_lock_irqsave(&pci_lock, flags);
2958
2959 bus->ops->read(bus, dev->devfn, PCI_COMMAND, 4, &cmd_status_dword);
2960
2961 irq_pending = (cmd_status_dword >> 16) & PCI_STATUS_INTERRUPT;
2962
2963 /*
2964 * Check interrupt status register to see whether our device
2965 * triggered the interrupt (when masking) or the next IRQ is
2966 * already pending (when unmasking).
2967 */
2968 if (mask != irq_pending) {
2969 mask_updated = false;
2970 goto done;
2971 }
2972
2973 origcmd = cmd_status_dword;
2974 newcmd = origcmd & ~PCI_COMMAND_INTX_DISABLE;
2975 if (mask)
2976 newcmd |= PCI_COMMAND_INTX_DISABLE;
2977 if (newcmd != origcmd)
2978 bus->ops->write(bus, dev->devfn, PCI_COMMAND, 2, newcmd);
2979
2980done:
2981 raw_spin_unlock_irqrestore(&pci_lock, flags);
2982
2983 return mask_updated;
2984}
2985
2986/**
2987 * pci_check_and_mask_intx - mask INTx on pending interrupt
2988 * @dev: the PCI device to operate on
2989 *
2990 * Check if the device dev has its INTx line asserted, mask it and
2991 * return true in that case. False is returned if not interrupt was
2992 * pending.
2993 */
2994bool pci_check_and_mask_intx(struct pci_dev *dev)
2995{
2996 return pci_check_and_set_intx_mask(dev, true);
2997}
2998EXPORT_SYMBOL_GPL(pci_check_and_mask_intx);
2999
3000/**
3001 * pci_check_and_unmask_intx - unmask INTx if no interrupt is pending
3002 * @dev: the PCI device to operate on
3003 *
3004 * Check if the device dev has its INTx line asserted, unmask it if not
3005 * and return true. False is returned and the mask remains active if
3006 * there was still an interrupt pending.
3007 */
3008bool pci_check_and_unmask_intx(struct pci_dev *dev)
3009{
3010 return pci_check_and_set_intx_mask(dev, false);
3011}
3012EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx);
3013
3014/**
3015 * pci_msi_off - disables any MSI or MSI-X capabilities
3016 * @dev: the PCI device to operate on
3017 *
3018 * If you want to use MSI, see pci_enable_msi() and friends.
3019 * This is a lower-level primitive that allows us to disable
3020 * MSI operation at the device level.
3021 */
3022void pci_msi_off(struct pci_dev *dev)
3023{
3024 int pos;
3025 u16 control;
3026
3027 /*
3028 * This looks like it could go in msi.c, but we need it even when
3029 * CONFIG_PCI_MSI=n. For the same reason, we can't use
3030 * dev->msi_cap or dev->msix_cap here.
3031 */
3032 pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
3033 if (pos) {
3034 pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
3035 control &= ~PCI_MSI_FLAGS_ENABLE;
3036 pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
3037 }
3038 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
3039 if (pos) {
3040 pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
3041 control &= ~PCI_MSIX_FLAGS_ENABLE;
3042 pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
3043 }
3044}
3045EXPORT_SYMBOL_GPL(pci_msi_off);
3046
3047int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
3048{
3049 return dma_set_max_seg_size(&dev->dev, size);
3050}
3051EXPORT_SYMBOL(pci_set_dma_max_seg_size);
3052
3053int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
3054{
3055 return dma_set_seg_boundary(&dev->dev, mask);
3056}
3057EXPORT_SYMBOL(pci_set_dma_seg_boundary);
3058
3059/**
3060 * pci_wait_for_pending_transaction - waits for pending transaction
3061 * @dev: the PCI device to operate on
3062 *
3063 * Return 0 if transaction is pending 1 otherwise.
3064 */
3065int pci_wait_for_pending_transaction(struct pci_dev *dev)
3066{
3067 if (!pci_is_pcie(dev))
3068 return 1;
3069
3070 return pci_wait_for_pending(dev, pci_pcie_cap(dev) + PCI_EXP_DEVSTA,
3071 PCI_EXP_DEVSTA_TRPND);
3072}
3073EXPORT_SYMBOL(pci_wait_for_pending_transaction);
3074
3075static int pcie_flr(struct pci_dev *dev, int probe)
3076{
3077 u32 cap;
3078
3079 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
3080 if (!(cap & PCI_EXP_DEVCAP_FLR))
3081 return -ENOTTY;
3082
3083 if (probe)
3084 return 0;
3085
3086 if (!pci_wait_for_pending_transaction(dev))
3087 dev_err(&dev->dev, "transaction is not cleared; proceeding with reset anyway\n");
3088
3089 pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR);
3090
3091 msleep(100);
3092
3093 return 0;
3094}
3095
3096static int pci_af_flr(struct pci_dev *dev, int probe)
3097{
3098 int pos;
3099 u8 cap;
3100
3101 pos = pci_find_capability(dev, PCI_CAP_ID_AF);
3102 if (!pos)
3103 return -ENOTTY;
3104
3105 pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
3106 if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
3107 return -ENOTTY;
3108
3109 if (probe)
3110 return 0;
3111
3112 /* Wait for Transaction Pending bit clean */
3113 if (pci_wait_for_pending(dev, pos + PCI_AF_STATUS, PCI_AF_STATUS_TP))
3114 goto clear;
3115
3116 dev_err(&dev->dev, "transaction is not cleared; "
3117 "proceeding with reset anyway\n");
3118
3119clear:
3120 pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
3121 msleep(100);
3122
3123 return 0;
3124}
3125
3126/**
3127 * pci_pm_reset - Put device into PCI_D3 and back into PCI_D0.
3128 * @dev: Device to reset.
3129 * @probe: If set, only check if the device can be reset this way.
3130 *
3131 * If @dev supports native PCI PM and its PCI_PM_CTRL_NO_SOFT_RESET flag is
3132 * unset, it will be reinitialized internally when going from PCI_D3hot to
3133 * PCI_D0. If that's the case and the device is not in a low-power state
3134 * already, force it into PCI_D3hot and back to PCI_D0, causing it to be reset.
3135 *
3136 * NOTE: This causes the caller to sleep for twice the device power transition
3137 * cooldown period, which for the D0->D3hot and D3hot->D0 transitions is 10 ms
3138 * by default (i.e. unless the @dev's d3_delay field has a different value).
3139 * Moreover, only devices in D0 can be reset by this function.
3140 */
3141static int pci_pm_reset(struct pci_dev *dev, int probe)
3142{
3143 u16 csr;
3144
3145 if (!dev->pm_cap)
3146 return -ENOTTY;
3147
3148 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
3149 if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
3150 return -ENOTTY;
3151
3152 if (probe)
3153 return 0;
3154
3155 if (dev->current_state != PCI_D0)
3156 return -EINVAL;
3157
3158 csr &= ~PCI_PM_CTRL_STATE_MASK;
3159 csr |= PCI_D3hot;
3160 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
3161 pci_dev_d3_sleep(dev);
3162
3163 csr &= ~PCI_PM_CTRL_STATE_MASK;
3164 csr |= PCI_D0;
3165 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
3166 pci_dev_d3_sleep(dev);
3167
3168 return 0;
3169}
3170
3171/**
3172 * pci_reset_bridge_secondary_bus - Reset the secondary bus on a PCI bridge.
3173 * @dev: Bridge device
3174 *
3175 * Use the bridge control register to assert reset on the secondary bus.
3176 * Devices on the secondary bus are left in power-on state.
3177 */
3178void pci_reset_bridge_secondary_bus(struct pci_dev *dev)
3179{
3180 u16 ctrl;
3181
3182 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &ctrl);
3183 ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
3184 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
3185 /*
3186 * PCI spec v3.0 7.6.4.2 requires minimum Trst of 1ms. Double
3187 * this to 2ms to ensure that we meet the minimum requirement.
3188 */
3189 msleep(2);
3190
3191 ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
3192 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
3193
3194 /*
3195 * Trhfa for conventional PCI is 2^25 clock cycles.
3196 * Assuming a minimum 33MHz clock this results in a 1s
3197 * delay before we can consider subordinate devices to
3198 * be re-initialized. PCIe has some ways to shorten this,
3199 * but we don't make use of them yet.
3200 */
3201 ssleep(1);
3202}
3203EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus);
3204
3205static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
3206{
3207 struct pci_dev *pdev;
3208
3209 if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self)
3210 return -ENOTTY;
3211
3212 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
3213 if (pdev != dev)
3214 return -ENOTTY;
3215
3216 if (probe)
3217 return 0;
3218
3219 pci_reset_bridge_secondary_bus(dev->bus->self);
3220
3221 return 0;
3222}
3223
3224static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe)
3225{
3226 int rc = -ENOTTY;
3227
3228 if (!hotplug || !try_module_get(hotplug->ops->owner))
3229 return rc;
3230
3231 if (hotplug->ops->reset_slot)
3232 rc = hotplug->ops->reset_slot(hotplug, probe);
3233
3234 module_put(hotplug->ops->owner);
3235
3236 return rc;
3237}
3238
3239static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe)
3240{
3241 struct pci_dev *pdev;
3242
3243 if (dev->subordinate || !dev->slot)
3244 return -ENOTTY;
3245
3246 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
3247 if (pdev != dev && pdev->slot == dev->slot)
3248 return -ENOTTY;
3249
3250 return pci_reset_hotplug_slot(dev->slot->hotplug, probe);
3251}
3252
3253static int __pci_dev_reset(struct pci_dev *dev, int probe)
3254{
3255 int rc;
3256
3257 might_sleep();
3258
3259 rc = pci_dev_specific_reset(dev, probe);
3260 if (rc != -ENOTTY)
3261 goto done;
3262
3263 rc = pcie_flr(dev, probe);
3264 if (rc != -ENOTTY)
3265 goto done;
3266
3267 rc = pci_af_flr(dev, probe);
3268 if (rc != -ENOTTY)
3269 goto done;
3270
3271 rc = pci_pm_reset(dev, probe);
3272 if (rc != -ENOTTY)
3273 goto done;
3274
3275 rc = pci_dev_reset_slot_function(dev, probe);
3276 if (rc != -ENOTTY)
3277 goto done;
3278
3279 rc = pci_parent_bus_reset(dev, probe);
3280done:
3281 return rc;
3282}
3283
3284static void pci_dev_lock(struct pci_dev *dev)
3285{
3286 pci_cfg_access_lock(dev);
3287 /* block PM suspend, driver probe, etc. */
3288 device_lock(&dev->dev);
3289}
3290
3291/* Return 1 on successful lock, 0 on contention */
3292static int pci_dev_trylock(struct pci_dev *dev)
3293{
3294 if (pci_cfg_access_trylock(dev)) {
3295 if (device_trylock(&dev->dev))
3296 return 1;
3297 pci_cfg_access_unlock(dev);
3298 }
3299
3300 return 0;
3301}
3302
3303static void pci_dev_unlock(struct pci_dev *dev)
3304{
3305 device_unlock(&dev->dev);
3306 pci_cfg_access_unlock(dev);
3307}
3308
3309static void pci_dev_save_and_disable(struct pci_dev *dev)
3310{
3311 /*
3312 * Wake-up device prior to save. PM registers default to D0 after
3313 * reset and a simple register restore doesn't reliably return
3314 * to a non-D0 state anyway.
3315 */
3316 pci_set_power_state(dev, PCI_D0);
3317
3318 pci_save_state(dev);
3319 /*
3320 * Disable the device by clearing the Command register, except for
3321 * INTx-disable which is set. This not only disables MMIO and I/O port
3322 * BARs, but also prevents the device from being Bus Master, preventing
3323 * DMA from the device including MSI/MSI-X interrupts. For PCI 2.3
3324 * compliant devices, INTx-disable prevents legacy interrupts.
3325 */
3326 pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
3327}
3328
3329static void pci_dev_restore(struct pci_dev *dev)
3330{
3331 pci_restore_state(dev);
3332}
3333
3334static int pci_dev_reset(struct pci_dev *dev, int probe)
3335{
3336 int rc;
3337
3338 if (!probe)
3339 pci_dev_lock(dev);
3340
3341 rc = __pci_dev_reset(dev, probe);
3342
3343 if (!probe)
3344 pci_dev_unlock(dev);
3345
3346 return rc;
3347}
3348/**
3349 * __pci_reset_function - reset a PCI device function
3350 * @dev: PCI device to reset
3351 *
3352 * Some devices allow an individual function to be reset without affecting
3353 * other functions in the same device. The PCI device must be responsive
3354 * to PCI config space in order to use this function.
3355 *
3356 * The device function is presumed to be unused when this function is called.
3357 * Resetting the device will make the contents of PCI configuration space
3358 * random, so any caller of this must be prepared to reinitialise the
3359 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
3360 * etc.
3361 *
3362 * Returns 0 if the device function was successfully reset or negative if the
3363 * device doesn't support resetting a single function.
3364 */
3365int __pci_reset_function(struct pci_dev *dev)
3366{
3367 return pci_dev_reset(dev, 0);
3368}
3369EXPORT_SYMBOL_GPL(__pci_reset_function);
3370
3371/**
3372 * __pci_reset_function_locked - reset a PCI device function while holding
3373 * the @dev mutex lock.
3374 * @dev: PCI device to reset
3375 *
3376 * Some devices allow an individual function to be reset without affecting
3377 * other functions in the same device. The PCI device must be responsive
3378 * to PCI config space in order to use this function.
3379 *
3380 * The device function is presumed to be unused and the caller is holding
3381 * the device mutex lock when this function is called.
3382 * Resetting the device will make the contents of PCI configuration space
3383 * random, so any caller of this must be prepared to reinitialise the
3384 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
3385 * etc.
3386 *
3387 * Returns 0 if the device function was successfully reset or negative if the
3388 * device doesn't support resetting a single function.
3389 */
3390int __pci_reset_function_locked(struct pci_dev *dev)
3391{
3392 return __pci_dev_reset(dev, 0);
3393}
3394EXPORT_SYMBOL_GPL(__pci_reset_function_locked);
3395
3396/**
3397 * pci_probe_reset_function - check whether the device can be safely reset
3398 * @dev: PCI device to reset
3399 *
3400 * Some devices allow an individual function to be reset without affecting
3401 * other functions in the same device. The PCI device must be responsive
3402 * to PCI config space in order to use this function.
3403 *
3404 * Returns 0 if the device function can be reset or negative if the
3405 * device doesn't support resetting a single function.
3406 */
3407int pci_probe_reset_function(struct pci_dev *dev)
3408{
3409 return pci_dev_reset(dev, 1);
3410}
3411
3412/**
3413 * pci_reset_function - quiesce and reset a PCI device function
3414 * @dev: PCI device to reset
3415 *
3416 * Some devices allow an individual function to be reset without affecting
3417 * other functions in the same device. The PCI device must be responsive
3418 * to PCI config space in order to use this function.
3419 *
3420 * This function does not just reset the PCI portion of a device, but
3421 * clears all the state associated with the device. This function differs
3422 * from __pci_reset_function in that it saves and restores device state
3423 * over the reset.
3424 *
3425 * Returns 0 if the device function was successfully reset or negative if the
3426 * device doesn't support resetting a single function.
3427 */
3428int pci_reset_function(struct pci_dev *dev)
3429{
3430 int rc;
3431
3432 rc = pci_dev_reset(dev, 1);
3433 if (rc)
3434 return rc;
3435
3436 pci_dev_save_and_disable(dev);
3437
3438 rc = pci_dev_reset(dev, 0);
3439
3440 pci_dev_restore(dev);
3441
3442 return rc;
3443}
3444EXPORT_SYMBOL_GPL(pci_reset_function);
3445
3446/**
3447 * pci_try_reset_function - quiesce and reset a PCI device function
3448 * @dev: PCI device to reset
3449 *
3450 * Same as above, except return -EAGAIN if unable to lock device.
3451 */
3452int pci_try_reset_function(struct pci_dev *dev)
3453{
3454 int rc;
3455
3456 rc = pci_dev_reset(dev, 1);
3457 if (rc)
3458 return rc;
3459
3460 pci_dev_save_and_disable(dev);
3461
3462 if (pci_dev_trylock(dev)) {
3463 rc = __pci_dev_reset(dev, 0);
3464 pci_dev_unlock(dev);
3465 } else
3466 rc = -EAGAIN;
3467
3468 pci_dev_restore(dev);
3469
3470 return rc;
3471}
3472EXPORT_SYMBOL_GPL(pci_try_reset_function);
3473
3474/* Lock devices from the top of the tree down */
3475static void pci_bus_lock(struct pci_bus *bus)
3476{
3477 struct pci_dev *dev;
3478
3479 list_for_each_entry(dev, &bus->devices, bus_list) {
3480 pci_dev_lock(dev);
3481 if (dev->subordinate)
3482 pci_bus_lock(dev->subordinate);
3483 }
3484}
3485
3486/* Unlock devices from the bottom of the tree up */
3487static void pci_bus_unlock(struct pci_bus *bus)
3488{
3489 struct pci_dev *dev;
3490
3491 list_for_each_entry(dev, &bus->devices, bus_list) {
3492 if (dev->subordinate)
3493 pci_bus_unlock(dev->subordinate);
3494 pci_dev_unlock(dev);
3495 }
3496}
3497
3498/* Return 1 on successful lock, 0 on contention */
3499static int pci_bus_trylock(struct pci_bus *bus)
3500{
3501 struct pci_dev *dev;
3502
3503 list_for_each_entry(dev, &bus->devices, bus_list) {
3504 if (!pci_dev_trylock(dev))
3505 goto unlock;
3506 if (dev->subordinate) {
3507 if (!pci_bus_trylock(dev->subordinate)) {
3508 pci_dev_unlock(dev);
3509 goto unlock;
3510 }
3511 }
3512 }
3513 return 1;
3514
3515unlock:
3516 list_for_each_entry_continue_reverse(dev, &bus->devices, bus_list) {
3517 if (dev->subordinate)
3518 pci_bus_unlock(dev->subordinate);
3519 pci_dev_unlock(dev);
3520 }
3521 return 0;
3522}
3523
3524/* Lock devices from the top of the tree down */
3525static void pci_slot_lock(struct pci_slot *slot)
3526{
3527 struct pci_dev *dev;
3528
3529 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3530 if (!dev->slot || dev->slot != slot)
3531 continue;
3532 pci_dev_lock(dev);
3533 if (dev->subordinate)
3534 pci_bus_lock(dev->subordinate);
3535 }
3536}
3537
3538/* Unlock devices from the bottom of the tree up */
3539static void pci_slot_unlock(struct pci_slot *slot)
3540{
3541 struct pci_dev *dev;
3542
3543 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3544 if (!dev->slot || dev->slot != slot)
3545 continue;
3546 if (dev->subordinate)
3547 pci_bus_unlock(dev->subordinate);
3548 pci_dev_unlock(dev);
3549 }
3550}
3551
3552/* Return 1 on successful lock, 0 on contention */
3553static int pci_slot_trylock(struct pci_slot *slot)
3554{
3555 struct pci_dev *dev;
3556
3557 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3558 if (!dev->slot || dev->slot != slot)
3559 continue;
3560 if (!pci_dev_trylock(dev))
3561 goto unlock;
3562 if (dev->subordinate) {
3563 if (!pci_bus_trylock(dev->subordinate)) {
3564 pci_dev_unlock(dev);
3565 goto unlock;
3566 }
3567 }
3568 }
3569 return 1;
3570
3571unlock:
3572 list_for_each_entry_continue_reverse(dev,
3573 &slot->bus->devices, bus_list) {
3574 if (!dev->slot || dev->slot != slot)
3575 continue;
3576 if (dev->subordinate)
3577 pci_bus_unlock(dev->subordinate);
3578 pci_dev_unlock(dev);
3579 }
3580 return 0;
3581}
3582
3583/* Save and disable devices from the top of the tree down */
3584static void pci_bus_save_and_disable(struct pci_bus *bus)
3585{
3586 struct pci_dev *dev;
3587
3588 list_for_each_entry(dev, &bus->devices, bus_list) {
3589 pci_dev_save_and_disable(dev);
3590 if (dev->subordinate)
3591 pci_bus_save_and_disable(dev->subordinate);
3592 }
3593}
3594
3595/*
3596 * Restore devices from top of the tree down - parent bridges need to be
3597 * restored before we can get to subordinate devices.
3598 */
3599static void pci_bus_restore(struct pci_bus *bus)
3600{
3601 struct pci_dev *dev;
3602
3603 list_for_each_entry(dev, &bus->devices, bus_list) {
3604 pci_dev_restore(dev);
3605 if (dev->subordinate)
3606 pci_bus_restore(dev->subordinate);
3607 }
3608}
3609
3610/* Save and disable devices from the top of the tree down */
3611static void pci_slot_save_and_disable(struct pci_slot *slot)
3612{
3613 struct pci_dev *dev;
3614
3615 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3616 if (!dev->slot || dev->slot != slot)
3617 continue;
3618 pci_dev_save_and_disable(dev);
3619 if (dev->subordinate)
3620 pci_bus_save_and_disable(dev->subordinate);
3621 }
3622}
3623
3624/*
3625 * Restore devices from top of the tree down - parent bridges need to be
3626 * restored before we can get to subordinate devices.
3627 */
3628static void pci_slot_restore(struct pci_slot *slot)
3629{
3630 struct pci_dev *dev;
3631
3632 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3633 if (!dev->slot || dev->slot != slot)
3634 continue;
3635 pci_dev_restore(dev);
3636 if (dev->subordinate)
3637 pci_bus_restore(dev->subordinate);
3638 }
3639}
3640
3641static int pci_slot_reset(struct pci_slot *slot, int probe)
3642{
3643 int rc;
3644
3645 if (!slot)
3646 return -ENOTTY;
3647
3648 if (!probe)
3649 pci_slot_lock(slot);
3650
3651 might_sleep();
3652
3653 rc = pci_reset_hotplug_slot(slot->hotplug, probe);
3654
3655 if (!probe)
3656 pci_slot_unlock(slot);
3657
3658 return rc;
3659}
3660
3661/**
3662 * pci_probe_reset_slot - probe whether a PCI slot can be reset
3663 * @slot: PCI slot to probe
3664 *
3665 * Return 0 if slot can be reset, negative if a slot reset is not supported.
3666 */
3667int pci_probe_reset_slot(struct pci_slot *slot)
3668{
3669 return pci_slot_reset(slot, 1);
3670}
3671EXPORT_SYMBOL_GPL(pci_probe_reset_slot);
3672
3673/**
3674 * pci_reset_slot - reset a PCI slot
3675 * @slot: PCI slot to reset
3676 *
3677 * A PCI bus may host multiple slots, each slot may support a reset mechanism
3678 * independent of other slots. For instance, some slots may support slot power
3679 * control. In the case of a 1:1 bus to slot architecture, this function may
3680 * wrap the bus reset to avoid spurious slot related events such as hotplug.
3681 * Generally a slot reset should be attempted before a bus reset. All of the
3682 * function of the slot and any subordinate buses behind the slot are reset
3683 * through this function. PCI config space of all devices in the slot and
3684 * behind the slot is saved before and restored after reset.
3685 *
3686 * Return 0 on success, non-zero on error.
3687 */
3688int pci_reset_slot(struct pci_slot *slot)
3689{
3690 int rc;
3691
3692 rc = pci_slot_reset(slot, 1);
3693 if (rc)
3694 return rc;
3695
3696 pci_slot_save_and_disable(slot);
3697
3698 rc = pci_slot_reset(slot, 0);
3699
3700 pci_slot_restore(slot);
3701
3702 return rc;
3703}
3704EXPORT_SYMBOL_GPL(pci_reset_slot);
3705
3706/**
3707 * pci_try_reset_slot - Try to reset a PCI slot
3708 * @slot: PCI slot to reset
3709 *
3710 * Same as above except return -EAGAIN if the slot cannot be locked
3711 */
3712int pci_try_reset_slot(struct pci_slot *slot)
3713{
3714 int rc;
3715
3716 rc = pci_slot_reset(slot, 1);
3717 if (rc)
3718 return rc;
3719
3720 pci_slot_save_and_disable(slot);
3721
3722 if (pci_slot_trylock(slot)) {
3723 might_sleep();
3724 rc = pci_reset_hotplug_slot(slot->hotplug, 0);
3725 pci_slot_unlock(slot);
3726 } else
3727 rc = -EAGAIN;
3728
3729 pci_slot_restore(slot);
3730
3731 return rc;
3732}
3733EXPORT_SYMBOL_GPL(pci_try_reset_slot);
3734
3735static int pci_bus_reset(struct pci_bus *bus, int probe)
3736{
3737 if (!bus->self)
3738 return -ENOTTY;
3739
3740 if (probe)
3741 return 0;
3742
3743 pci_bus_lock(bus);
3744
3745 might_sleep();
3746
3747 pci_reset_bridge_secondary_bus(bus->self);
3748
3749 pci_bus_unlock(bus);
3750
3751 return 0;
3752}
3753
3754/**
3755 * pci_probe_reset_bus - probe whether a PCI bus can be reset
3756 * @bus: PCI bus to probe
3757 *
3758 * Return 0 if bus can be reset, negative if a bus reset is not supported.
3759 */
3760int pci_probe_reset_bus(struct pci_bus *bus)
3761{
3762 return pci_bus_reset(bus, 1);
3763}
3764EXPORT_SYMBOL_GPL(pci_probe_reset_bus);
3765
3766/**
3767 * pci_reset_bus - reset a PCI bus
3768 * @bus: top level PCI bus to reset
3769 *
3770 * Do a bus reset on the given bus and any subordinate buses, saving
3771 * and restoring state of all devices.
3772 *
3773 * Return 0 on success, non-zero on error.
3774 */
3775int pci_reset_bus(struct pci_bus *bus)
3776{
3777 int rc;
3778
3779 rc = pci_bus_reset(bus, 1);
3780 if (rc)
3781 return rc;
3782
3783 pci_bus_save_and_disable(bus);
3784
3785 rc = pci_bus_reset(bus, 0);
3786
3787 pci_bus_restore(bus);
3788
3789 return rc;
3790}
3791EXPORT_SYMBOL_GPL(pci_reset_bus);
3792
3793/**
3794 * pci_try_reset_bus - Try to reset a PCI bus
3795 * @bus: top level PCI bus to reset
3796 *
3797 * Same as above except return -EAGAIN if the bus cannot be locked
3798 */
3799int pci_try_reset_bus(struct pci_bus *bus)
3800{
3801 int rc;
3802
3803 rc = pci_bus_reset(bus, 1);
3804 if (rc)
3805 return rc;
3806
3807 pci_bus_save_and_disable(bus);
3808
3809 if (pci_bus_trylock(bus)) {
3810 might_sleep();
3811 pci_reset_bridge_secondary_bus(bus->self);
3812 pci_bus_unlock(bus);
3813 } else
3814 rc = -EAGAIN;
3815
3816 pci_bus_restore(bus);
3817
3818 return rc;
3819}
3820EXPORT_SYMBOL_GPL(pci_try_reset_bus);
3821
3822/**
3823 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
3824 * @dev: PCI device to query
3825 *
3826 * Returns mmrbc: maximum designed memory read count in bytes
3827 * or appropriate error value.
3828 */
3829int pcix_get_max_mmrbc(struct pci_dev *dev)
3830{
3831 int cap;
3832 u32 stat;
3833
3834 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3835 if (!cap)
3836 return -EINVAL;
3837
3838 if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
3839 return -EINVAL;
3840
3841 return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21);
3842}
3843EXPORT_SYMBOL(pcix_get_max_mmrbc);
3844
3845/**
3846 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
3847 * @dev: PCI device to query
3848 *
3849 * Returns mmrbc: maximum memory read count in bytes
3850 * or appropriate error value.
3851 */
3852int pcix_get_mmrbc(struct pci_dev *dev)
3853{
3854 int cap;
3855 u16 cmd;
3856
3857 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3858 if (!cap)
3859 return -EINVAL;
3860
3861 if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
3862 return -EINVAL;
3863
3864 return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
3865}
3866EXPORT_SYMBOL(pcix_get_mmrbc);
3867
3868/**
3869 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
3870 * @dev: PCI device to query
3871 * @mmrbc: maximum memory read count in bytes
3872 * valid values are 512, 1024, 2048, 4096
3873 *
3874 * If possible sets maximum memory read byte count, some bridges have erratas
3875 * that prevent this.
3876 */
3877int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
3878{
3879 int cap;
3880 u32 stat, v, o;
3881 u16 cmd;
3882
3883 if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
3884 return -EINVAL;
3885
3886 v = ffs(mmrbc) - 10;
3887
3888 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
3889 if (!cap)
3890 return -EINVAL;
3891
3892 if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
3893 return -EINVAL;
3894
3895 if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
3896 return -E2BIG;
3897
3898 if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
3899 return -EINVAL;
3900
3901 o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
3902 if (o != v) {
3903 if (v > o && (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
3904 return -EIO;
3905
3906 cmd &= ~PCI_X_CMD_MAX_READ;
3907 cmd |= v << 2;
3908 if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd))
3909 return -EIO;
3910 }
3911 return 0;
3912}
3913EXPORT_SYMBOL(pcix_set_mmrbc);
3914
3915/**
3916 * pcie_get_readrq - get PCI Express read request size
3917 * @dev: PCI device to query
3918 *
3919 * Returns maximum memory read request in bytes
3920 * or appropriate error value.
3921 */
3922int pcie_get_readrq(struct pci_dev *dev)
3923{
3924 u16 ctl;
3925
3926 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
3927
3928 return 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
3929}
3930EXPORT_SYMBOL(pcie_get_readrq);
3931
3932/**
3933 * pcie_set_readrq - set PCI Express maximum memory read request
3934 * @dev: PCI device to query
3935 * @rq: maximum memory read count in bytes
3936 * valid values are 128, 256, 512, 1024, 2048, 4096
3937 *
3938 * If possible sets maximum memory read request in bytes
3939 */
3940int pcie_set_readrq(struct pci_dev *dev, int rq)
3941{
3942 u16 v;
3943
3944 if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
3945 return -EINVAL;
3946
3947 /*
3948 * If using the "performance" PCIe config, we clamp the
3949 * read rq size to the max packet size to prevent the
3950 * host bridge generating requests larger than we can
3951 * cope with
3952 */
3953 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
3954 int mps = pcie_get_mps(dev);
3955
3956 if (mps < rq)
3957 rq = mps;
3958 }
3959
3960 v = (ffs(rq) - 8) << 12;
3961
3962 return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
3963 PCI_EXP_DEVCTL_READRQ, v);
3964}
3965EXPORT_SYMBOL(pcie_set_readrq);
3966
3967/**
3968 * pcie_get_mps - get PCI Express maximum payload size
3969 * @dev: PCI device to query
3970 *
3971 * Returns maximum payload size in bytes
3972 */
3973int pcie_get_mps(struct pci_dev *dev)
3974{
3975 u16 ctl;
3976
3977 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
3978
3979 return 128 << ((ctl & PCI_EXP_DEVCTL_PAYLOAD) >> 5);
3980}
3981EXPORT_SYMBOL(pcie_get_mps);
3982
3983/**
3984 * pcie_set_mps - set PCI Express maximum payload size
3985 * @dev: PCI device to query
3986 * @mps: maximum payload size in bytes
3987 * valid values are 128, 256, 512, 1024, 2048, 4096
3988 *
3989 * If possible sets maximum payload size
3990 */
3991int pcie_set_mps(struct pci_dev *dev, int mps)
3992{
3993 u16 v;
3994
3995 if (mps < 128 || mps > 4096 || !is_power_of_2(mps))
3996 return -EINVAL;
3997
3998 v = ffs(mps) - 8;
3999 if (v > dev->pcie_mpss)
4000 return -EINVAL;
4001 v <<= 5;
4002
4003 return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
4004 PCI_EXP_DEVCTL_PAYLOAD, v);
4005}
4006EXPORT_SYMBOL(pcie_set_mps);
4007
4008/**
4009 * pcie_get_minimum_link - determine minimum link settings of a PCI device
4010 * @dev: PCI device to query
4011 * @speed: storage for minimum speed
4012 * @width: storage for minimum width
4013 *
4014 * This function will walk up the PCI device chain and determine the minimum
4015 * link width and speed of the device.
4016 */
4017int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed,
4018 enum pcie_link_width *width)
4019{
4020 int ret;
4021
4022 *speed = PCI_SPEED_UNKNOWN;
4023 *width = PCIE_LNK_WIDTH_UNKNOWN;
4024
4025 while (dev) {
4026 u16 lnksta;
4027 enum pci_bus_speed next_speed;
4028 enum pcie_link_width next_width;
4029
4030 ret = pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);
4031 if (ret)
4032 return ret;
4033
4034 next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
4035 next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >>
4036 PCI_EXP_LNKSTA_NLW_SHIFT;
4037
4038 if (next_speed < *speed)
4039 *speed = next_speed;
4040
4041 if (next_width < *width)
4042 *width = next_width;
4043
4044 dev = dev->bus->self;
4045 }
4046
4047 return 0;
4048}
4049EXPORT_SYMBOL(pcie_get_minimum_link);
4050
4051/**
4052 * pci_select_bars - Make BAR mask from the type of resource
4053 * @dev: the PCI device for which BAR mask is made
4054 * @flags: resource type mask to be selected
4055 *
4056 * This helper routine makes bar mask from the type of resource.
4057 */
4058int pci_select_bars(struct pci_dev *dev, unsigned long flags)
4059{
4060 int i, bars = 0;
4061 for (i = 0; i < PCI_NUM_RESOURCES; i++)
4062 if (pci_resource_flags(dev, i) & flags)
4063 bars |= (1 << i);
4064 return bars;
4065}
4066
4067/**
4068 * pci_resource_bar - get position of the BAR associated with a resource
4069 * @dev: the PCI device
4070 * @resno: the resource number
4071 * @type: the BAR type to be filled in
4072 *
4073 * Returns BAR position in config space, or 0 if the BAR is invalid.
4074 */
4075int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type)
4076{
4077 int reg;
4078
4079 if (resno < PCI_ROM_RESOURCE) {
4080 *type = pci_bar_unknown;
4081 return PCI_BASE_ADDRESS_0 + 4 * resno;
4082 } else if (resno == PCI_ROM_RESOURCE) {
4083 *type = pci_bar_mem32;
4084 return dev->rom_base_reg;
4085 } else if (resno < PCI_BRIDGE_RESOURCES) {
4086 /* device specific resource */
4087 reg = pci_iov_resource_bar(dev, resno, type);
4088 if (reg)
4089 return reg;
4090 }
4091
4092 dev_err(&dev->dev, "BAR %d: invalid resource\n", resno);
4093 return 0;
4094}
4095
4096/* Some architectures require additional programming to enable VGA */
4097static arch_set_vga_state_t arch_set_vga_state;
4098
4099void __init pci_register_set_vga_state(arch_set_vga_state_t func)
4100{
4101 arch_set_vga_state = func; /* NULL disables */
4102}
4103
4104static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode,
4105 unsigned int command_bits, u32 flags)
4106{
4107 if (arch_set_vga_state)
4108 return arch_set_vga_state(dev, decode, command_bits,
4109 flags);
4110 return 0;
4111}
4112
4113/**
4114 * pci_set_vga_state - set VGA decode state on device and parents if requested
4115 * @dev: the PCI device
4116 * @decode: true = enable decoding, false = disable decoding
4117 * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
4118 * @flags: traverse ancestors and change bridges
4119 * CHANGE_BRIDGE_ONLY / CHANGE_BRIDGE
4120 */
4121int pci_set_vga_state(struct pci_dev *dev, bool decode,
4122 unsigned int command_bits, u32 flags)
4123{
4124 struct pci_bus *bus;
4125 struct pci_dev *bridge;
4126 u16 cmd;
4127 int rc;
4128
4129 WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) & (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY)));
4130
4131 /* ARCH specific VGA enables */
4132 rc = pci_set_vga_state_arch(dev, decode, command_bits, flags);
4133 if (rc)
4134 return rc;
4135
4136 if (flags & PCI_VGA_STATE_CHANGE_DECODES) {
4137 pci_read_config_word(dev, PCI_COMMAND, &cmd);
4138 if (decode == true)
4139 cmd |= command_bits;
4140 else
4141 cmd &= ~command_bits;
4142 pci_write_config_word(dev, PCI_COMMAND, cmd);
4143 }
4144
4145 if (!(flags & PCI_VGA_STATE_CHANGE_BRIDGE))
4146 return 0;
4147
4148 bus = dev->bus;
4149 while (bus) {
4150 bridge = bus->self;
4151 if (bridge) {
4152 pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
4153 &cmd);
4154 if (decode == true)
4155 cmd |= PCI_BRIDGE_CTL_VGA;
4156 else
4157 cmd &= ~PCI_BRIDGE_CTL_VGA;
4158 pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
4159 cmd);
4160 }
4161 bus = bus->parent;
4162 }
4163 return 0;
4164}
4165
4166bool pci_device_is_present(struct pci_dev *pdev)
4167{
4168 u32 v;
4169
4170 return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0);
4171}
4172EXPORT_SYMBOL_GPL(pci_device_is_present);
4173
4174#define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
4175static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
4176static DEFINE_SPINLOCK(resource_alignment_lock);
4177
4178/**
4179 * pci_specified_resource_alignment - get resource alignment specified by user.
4180 * @dev: the PCI device to get
4181 *
4182 * RETURNS: Resource alignment if it is specified.
4183 * Zero if it is not specified.
4184 */
4185static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
4186{
4187 int seg, bus, slot, func, align_order, count;
4188 resource_size_t align = 0;
4189 char *p;
4190
4191 spin_lock(&resource_alignment_lock);
4192 p = resource_alignment_param;
4193 while (*p) {
4194 count = 0;
4195 if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
4196 p[count] == '@') {
4197 p += count + 1;
4198 } else {
4199 align_order = -1;
4200 }
4201 if (sscanf(p, "%x:%x:%x.%x%n",
4202 &seg, &bus, &slot, &func, &count) != 4) {
4203 seg = 0;
4204 if (sscanf(p, "%x:%x.%x%n",
4205 &bus, &slot, &func, &count) != 3) {
4206 /* Invalid format */
4207 printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
4208 p);
4209 break;
4210 }
4211 }
4212 p += count;
4213 if (seg == pci_domain_nr(dev->bus) &&
4214 bus == dev->bus->number &&
4215 slot == PCI_SLOT(dev->devfn) &&
4216 func == PCI_FUNC(dev->devfn)) {
4217 if (align_order == -1) {
4218 align = PAGE_SIZE;
4219 } else {
4220 align = 1 << align_order;
4221 }
4222 /* Found */
4223 break;
4224 }
4225 if (*p != ';' && *p != ',') {
4226 /* End of param or invalid format */
4227 break;
4228 }
4229 p++;
4230 }
4231 spin_unlock(&resource_alignment_lock);
4232 return align;
4233}
4234
4235/*
4236 * This function disables memory decoding and releases memory resources
4237 * of the device specified by kernel's boot parameter 'pci=resource_alignment='.
4238 * It also rounds up size to specified alignment.
4239 * Later on, the kernel will assign page-aligned memory resource back
4240 * to the device.
4241 */
4242void pci_reassigndev_resource_alignment(struct pci_dev *dev)
4243{
4244 int i;
4245 struct resource *r;
4246 resource_size_t align, size;
4247 u16 command;
4248
4249 /* check if specified PCI is target device to reassign */
4250 align = pci_specified_resource_alignment(dev);
4251 if (!align)
4252 return;
4253
4254 if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL &&
4255 (dev->class >> 8) == PCI_CLASS_BRIDGE_HOST) {
4256 dev_warn(&dev->dev,
4257 "Can't reassign resources to host bridge.\n");
4258 return;
4259 }
4260
4261 dev_info(&dev->dev,
4262 "Disabling memory decoding and releasing memory resources.\n");
4263 pci_read_config_word(dev, PCI_COMMAND, &command);
4264 command &= ~PCI_COMMAND_MEMORY;
4265 pci_write_config_word(dev, PCI_COMMAND, command);
4266
4267 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
4268 r = &dev->resource[i];
4269 if (!(r->flags & IORESOURCE_MEM))
4270 continue;
4271 size = resource_size(r);
4272 if (size < align) {
4273 size = align;
4274 dev_info(&dev->dev,
4275 "Rounding up size of resource #%d to %#llx.\n",
4276 i, (unsigned long long)size);
4277 }
4278 r->flags |= IORESOURCE_UNSET;
4279 r->end = size - 1;
4280 r->start = 0;
4281 }
4282 /* Need to disable bridge's resource window,
4283 * to enable the kernel to reassign new resource
4284 * window later on.
4285 */
4286 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
4287 (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
4288 for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) {
4289 r = &dev->resource[i];
4290 if (!(r->flags & IORESOURCE_MEM))
4291 continue;
4292 r->flags |= IORESOURCE_UNSET;
4293 r->end = resource_size(r) - 1;
4294 r->start = 0;
4295 }
4296 pci_disable_bridge_window(dev);
4297 }
4298}
4299
4300static ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
4301{
4302 if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
4303 count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
4304 spin_lock(&resource_alignment_lock);
4305 strncpy(resource_alignment_param, buf, count);
4306 resource_alignment_param[count] = '\0';
4307 spin_unlock(&resource_alignment_lock);
4308 return count;
4309}
4310
4311static ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
4312{
4313 size_t count;
4314 spin_lock(&resource_alignment_lock);
4315 count = snprintf(buf, size, "%s", resource_alignment_param);
4316 spin_unlock(&resource_alignment_lock);
4317 return count;
4318}
4319
4320static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
4321{
4322 return pci_get_resource_alignment_param(buf, PAGE_SIZE);
4323}
4324
4325static ssize_t pci_resource_alignment_store(struct bus_type *bus,
4326 const char *buf, size_t count)
4327{
4328 return pci_set_resource_alignment_param(buf, count);
4329}
4330
4331BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
4332 pci_resource_alignment_store);
4333
4334static int __init pci_resource_alignment_sysfs_init(void)
4335{
4336 return bus_create_file(&pci_bus_type,
4337 &bus_attr_resource_alignment);
4338}
4339
4340late_initcall(pci_resource_alignment_sysfs_init);
4341
4342static void pci_no_domains(void)
4343{
4344#ifdef CONFIG_PCI_DOMAINS
4345 pci_domains_supported = 0;
4346#endif
4347}
4348
4349/**
4350 * pci_ext_cfg_avail - can we access extended PCI config space?
4351 *
4352 * Returns 1 if we can access PCI extended config space (offsets
4353 * greater than 0xff). This is the default implementation. Architecture
4354 * implementations can override this.
4355 */
4356int __weak pci_ext_cfg_avail(void)
4357{
4358 return 1;
4359}
4360
4361void __weak pci_fixup_cardbus(struct pci_bus *bus)
4362{
4363}
4364EXPORT_SYMBOL(pci_fixup_cardbus);
4365
4366static int __init pci_setup(char *str)
4367{
4368 while (str) {
4369 char *k = strchr(str, ',');
4370 if (k)
4371 *k++ = 0;
4372 if (*str && (str = pcibios_setup(str)) && *str) {
4373 if (!strcmp(str, "nomsi")) {
4374 pci_no_msi();
4375 } else if (!strcmp(str, "noaer")) {
4376 pci_no_aer();
4377 } else if (!strncmp(str, "realloc=", 8)) {
4378 pci_realloc_get_opt(str + 8);
4379 } else if (!strncmp(str, "realloc", 7)) {
4380 pci_realloc_get_opt("on");
4381 } else if (!strcmp(str, "nodomains")) {
4382 pci_no_domains();
4383 } else if (!strncmp(str, "noari", 5)) {
4384 pcie_ari_disabled = true;
4385 } else if (!strncmp(str, "cbiosize=", 9)) {
4386 pci_cardbus_io_size = memparse(str + 9, &str);
4387 } else if (!strncmp(str, "cbmemsize=", 10)) {
4388 pci_cardbus_mem_size = memparse(str + 10, &str);
4389 } else if (!strncmp(str, "resource_alignment=", 19)) {
4390 pci_set_resource_alignment_param(str + 19,
4391 strlen(str + 19));
4392 } else if (!strncmp(str, "ecrc=", 5)) {
4393 pcie_ecrc_get_policy(str + 5);
4394 } else if (!strncmp(str, "hpiosize=", 9)) {
4395 pci_hotplug_io_size = memparse(str + 9, &str);
4396 } else if (!strncmp(str, "hpmemsize=", 10)) {
4397 pci_hotplug_mem_size = memparse(str + 10, &str);
4398 } else if (!strncmp(str, "pcie_bus_tune_off", 17)) {
4399 pcie_bus_config = PCIE_BUS_TUNE_OFF;
4400 } else if (!strncmp(str, "pcie_bus_safe", 13)) {
4401 pcie_bus_config = PCIE_BUS_SAFE;
4402 } else if (!strncmp(str, "pcie_bus_perf", 13)) {
4403 pcie_bus_config = PCIE_BUS_PERFORMANCE;
4404 } else if (!strncmp(str, "pcie_bus_peer2peer", 18)) {
4405 pcie_bus_config = PCIE_BUS_PEER2PEER;
4406 } else if (!strncmp(str, "pcie_scan_all", 13)) {
4407 pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS);
4408 } else {
4409 printk(KERN_ERR "PCI: Unknown option `%s'\n",
4410 str);
4411 }
4412 }
4413 str = k;
4414 }
4415 return 0;
4416}
4417early_param("pci", pci_setup);
4418
4419EXPORT_SYMBOL(pci_reenable_device);
4420EXPORT_SYMBOL(pci_enable_device_io);
4421EXPORT_SYMBOL(pci_enable_device_mem);
4422EXPORT_SYMBOL(pci_enable_device);
4423EXPORT_SYMBOL(pcim_enable_device);
4424EXPORT_SYMBOL(pcim_pin_device);
4425EXPORT_SYMBOL(pci_disable_device);
4426EXPORT_SYMBOL(pci_find_capability);
4427EXPORT_SYMBOL(pci_bus_find_capability);
4428EXPORT_SYMBOL(pci_release_regions);
4429EXPORT_SYMBOL(pci_request_regions);
4430EXPORT_SYMBOL(pci_request_regions_exclusive);
4431EXPORT_SYMBOL(pci_release_region);
4432EXPORT_SYMBOL(pci_request_region);
4433EXPORT_SYMBOL(pci_request_region_exclusive);
4434EXPORT_SYMBOL(pci_release_selected_regions);
4435EXPORT_SYMBOL(pci_request_selected_regions);
4436EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
4437EXPORT_SYMBOL(pci_set_master);
4438EXPORT_SYMBOL(pci_clear_master);
4439EXPORT_SYMBOL(pci_set_mwi);
4440EXPORT_SYMBOL(pci_try_set_mwi);
4441EXPORT_SYMBOL(pci_clear_mwi);
4442EXPORT_SYMBOL_GPL(pci_intx);
4443EXPORT_SYMBOL(pci_assign_resource);
4444EXPORT_SYMBOL(pci_find_parent_resource);
4445EXPORT_SYMBOL(pci_select_bars);
4446
4447EXPORT_SYMBOL(pci_set_power_state);
4448EXPORT_SYMBOL(pci_save_state);
4449EXPORT_SYMBOL(pci_restore_state);
4450EXPORT_SYMBOL(pci_pme_capable);
4451EXPORT_SYMBOL(pci_pme_active);
4452EXPORT_SYMBOL(pci_wake_from_d3);
4453EXPORT_SYMBOL(pci_prepare_to_sleep);
4454EXPORT_SYMBOL(pci_back_from_sleep);
4455EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);