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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCI Bus Services, see include/linux/pci.h for further explanation.
4 *
5 * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
6 * David Mosberger-Tang
7 *
8 * Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
9 */
10
11#include <linux/acpi.h>
12#include <linux/kernel.h>
13#include <linux/delay.h>
14#include <linux/dmi.h>
15#include <linux/init.h>
16#include <linux/of.h>
17#include <linux/of_pci.h>
18#include <linux/pci.h>
19#include <linux/pm.h>
20#include <linux/slab.h>
21#include <linux/module.h>
22#include <linux/spinlock.h>
23#include <linux/string.h>
24#include <linux/log2.h>
25#include <linux/logic_pio.h>
26#include <linux/pci-aspm.h>
27#include <linux/pm_wakeup.h>
28#include <linux/interrupt.h>
29#include <linux/device.h>
30#include <linux/pm_runtime.h>
31#include <linux/pci_hotplug.h>
32#include <linux/vmalloc.h>
33#include <linux/pci-ats.h>
34#include <asm/setup.h>
35#include <asm/dma.h>
36#include <linux/aer.h>
37#include "pci.h"
38
39const char *pci_power_names[] = {
40 "error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
41};
42EXPORT_SYMBOL_GPL(pci_power_names);
43
44int isa_dma_bridge_buggy;
45EXPORT_SYMBOL(isa_dma_bridge_buggy);
46
47int pci_pci_problems;
48EXPORT_SYMBOL(pci_pci_problems);
49
50unsigned int pci_pm_d3_delay;
51
52static void pci_pme_list_scan(struct work_struct *work);
53
54static LIST_HEAD(pci_pme_list);
55static DEFINE_MUTEX(pci_pme_list_mutex);
56static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan);
57
58struct pci_pme_device {
59 struct list_head list;
60 struct pci_dev *dev;
61};
62
63#define PME_TIMEOUT 1000 /* How long between PME checks */
64
65static void pci_dev_d3_sleep(struct pci_dev *dev)
66{
67 unsigned int delay = dev->d3_delay;
68
69 if (delay < pci_pm_d3_delay)
70 delay = pci_pm_d3_delay;
71
72 if (delay)
73 msleep(delay);
74}
75
76#ifdef CONFIG_PCI_DOMAINS
77int pci_domains_supported = 1;
78#endif
79
80#define DEFAULT_CARDBUS_IO_SIZE (256)
81#define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
82/* pci=cbmemsize=nnM,cbiosize=nn can override this */
83unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
84unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
85
86#define DEFAULT_HOTPLUG_IO_SIZE (256)
87#define DEFAULT_HOTPLUG_MEM_SIZE (2*1024*1024)
88/* pci=hpmemsize=nnM,hpiosize=nn can override this */
89unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE;
90unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
91
92#define DEFAULT_HOTPLUG_BUS_SIZE 1
93unsigned long pci_hotplug_bus_size = DEFAULT_HOTPLUG_BUS_SIZE;
94
95enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_DEFAULT;
96
97/*
98 * The default CLS is used if arch didn't set CLS explicitly and not
99 * all pci devices agree on the same value. Arch can override either
100 * the dfl or actual value as it sees fit. Don't forget this is
101 * measured in 32-bit words, not bytes.
102 */
103u8 pci_dfl_cache_line_size = L1_CACHE_BYTES >> 2;
104u8 pci_cache_line_size;
105
106/*
107 * If we set up a device for bus mastering, we need to check the latency
108 * timer as certain BIOSes forget to set it properly.
109 */
110unsigned int pcibios_max_latency = 255;
111
112/* If set, the PCIe ARI capability will not be used. */
113static bool pcie_ari_disabled;
114
115/* Disable bridge_d3 for all PCIe ports */
116static bool pci_bridge_d3_disable;
117/* Force bridge_d3 for all PCIe ports */
118static bool pci_bridge_d3_force;
119
120static int __init pcie_port_pm_setup(char *str)
121{
122 if (!strcmp(str, "off"))
123 pci_bridge_d3_disable = true;
124 else if (!strcmp(str, "force"))
125 pci_bridge_d3_force = true;
126 return 1;
127}
128__setup("pcie_port_pm=", pcie_port_pm_setup);
129
130/* Time to wait after a reset for device to become responsive */
131#define PCIE_RESET_READY_POLL_MS 60000
132
133/**
134 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
135 * @bus: pointer to PCI bus structure to search
136 *
137 * Given a PCI bus, returns the highest PCI bus number present in the set
138 * including the given PCI bus and its list of child PCI buses.
139 */
140unsigned char pci_bus_max_busnr(struct pci_bus *bus)
141{
142 struct pci_bus *tmp;
143 unsigned char max, n;
144
145 max = bus->busn_res.end;
146 list_for_each_entry(tmp, &bus->children, node) {
147 n = pci_bus_max_busnr(tmp);
148 if (n > max)
149 max = n;
150 }
151 return max;
152}
153EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
154
155#ifdef CONFIG_HAS_IOMEM
156void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
157{
158 struct resource *res = &pdev->resource[bar];
159
160 /*
161 * Make sure the BAR is actually a memory resource, not an IO resource
162 */
163 if (res->flags & IORESOURCE_UNSET || !(res->flags & IORESOURCE_MEM)) {
164 pci_warn(pdev, "can't ioremap BAR %d: %pR\n", bar, res);
165 return NULL;
166 }
167 return ioremap_nocache(res->start, resource_size(res));
168}
169EXPORT_SYMBOL_GPL(pci_ioremap_bar);
170
171void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar)
172{
173 /*
174 * Make sure the BAR is actually a memory resource, not an IO resource
175 */
176 if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
177 WARN_ON(1);
178 return NULL;
179 }
180 return ioremap_wc(pci_resource_start(pdev, bar),
181 pci_resource_len(pdev, bar));
182}
183EXPORT_SYMBOL_GPL(pci_ioremap_wc_bar);
184#endif
185
186
187static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
188 u8 pos, int cap, int *ttl)
189{
190 u8 id;
191 u16 ent;
192
193 pci_bus_read_config_byte(bus, devfn, pos, &pos);
194
195 while ((*ttl)--) {
196 if (pos < 0x40)
197 break;
198 pos &= ~3;
199 pci_bus_read_config_word(bus, devfn, pos, &ent);
200
201 id = ent & 0xff;
202 if (id == 0xff)
203 break;
204 if (id == cap)
205 return pos;
206 pos = (ent >> 8);
207 }
208 return 0;
209}
210
211static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
212 u8 pos, int cap)
213{
214 int ttl = PCI_FIND_CAP_TTL;
215
216 return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
217}
218
219int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
220{
221 return __pci_find_next_cap(dev->bus, dev->devfn,
222 pos + PCI_CAP_LIST_NEXT, cap);
223}
224EXPORT_SYMBOL_GPL(pci_find_next_capability);
225
226static int __pci_bus_find_cap_start(struct pci_bus *bus,
227 unsigned int devfn, u8 hdr_type)
228{
229 u16 status;
230
231 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
232 if (!(status & PCI_STATUS_CAP_LIST))
233 return 0;
234
235 switch (hdr_type) {
236 case PCI_HEADER_TYPE_NORMAL:
237 case PCI_HEADER_TYPE_BRIDGE:
238 return PCI_CAPABILITY_LIST;
239 case PCI_HEADER_TYPE_CARDBUS:
240 return PCI_CB_CAPABILITY_LIST;
241 }
242
243 return 0;
244}
245
246/**
247 * pci_find_capability - query for devices' capabilities
248 * @dev: PCI device to query
249 * @cap: capability code
250 *
251 * Tell if a device supports a given PCI capability.
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. Possible values for @cap:
255 *
256 * %PCI_CAP_ID_PM Power Management
257 * %PCI_CAP_ID_AGP Accelerated Graphics Port
258 * %PCI_CAP_ID_VPD Vital Product Data
259 * %PCI_CAP_ID_SLOTID Slot Identification
260 * %PCI_CAP_ID_MSI Message Signalled Interrupts
261 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
262 * %PCI_CAP_ID_PCIX PCI-X
263 * %PCI_CAP_ID_EXP PCI Express
264 */
265int pci_find_capability(struct pci_dev *dev, int cap)
266{
267 int pos;
268
269 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
270 if (pos)
271 pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
272
273 return pos;
274}
275EXPORT_SYMBOL(pci_find_capability);
276
277/**
278 * pci_bus_find_capability - query for devices' capabilities
279 * @bus: the PCI bus to query
280 * @devfn: PCI device to query
281 * @cap: capability code
282 *
283 * Like pci_find_capability() but works for pci devices that do not have a
284 * pci_dev structure set up yet.
285 *
286 * Returns the address of the requested capability structure within the
287 * device's PCI configuration space or 0 in case the device does not
288 * support it.
289 */
290int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
291{
292 int pos;
293 u8 hdr_type;
294
295 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
296
297 pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
298 if (pos)
299 pos = __pci_find_next_cap(bus, devfn, pos, cap);
300
301 return pos;
302}
303EXPORT_SYMBOL(pci_bus_find_capability);
304
305/**
306 * pci_find_next_ext_capability - Find an extended capability
307 * @dev: PCI device to query
308 * @start: address at which to start looking (0 to start at beginning of list)
309 * @cap: capability code
310 *
311 * Returns the address of the next matching extended capability structure
312 * within the device's PCI configuration space or 0 if the device does
313 * not support it. Some capabilities can occur several times, e.g., the
314 * vendor-specific capability, and this provides a way to find them all.
315 */
316int pci_find_next_ext_capability(struct pci_dev *dev, int start, int cap)
317{
318 u32 header;
319 int ttl;
320 int pos = PCI_CFG_SPACE_SIZE;
321
322 /* minimum 8 bytes per capability */
323 ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
324
325 if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
326 return 0;
327
328 if (start)
329 pos = start;
330
331 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
332 return 0;
333
334 /*
335 * If we have no capabilities, this is indicated by cap ID,
336 * cap version and next pointer all being 0.
337 */
338 if (header == 0)
339 return 0;
340
341 while (ttl-- > 0) {
342 if (PCI_EXT_CAP_ID(header) == cap && pos != start)
343 return pos;
344
345 pos = PCI_EXT_CAP_NEXT(header);
346 if (pos < PCI_CFG_SPACE_SIZE)
347 break;
348
349 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
350 break;
351 }
352
353 return 0;
354}
355EXPORT_SYMBOL_GPL(pci_find_next_ext_capability);
356
357/**
358 * pci_find_ext_capability - Find an extended capability
359 * @dev: PCI device to query
360 * @cap: capability code
361 *
362 * Returns the address of the requested extended capability structure
363 * within the device's PCI configuration space or 0 if the device does
364 * not support it. Possible values for @cap:
365 *
366 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
367 * %PCI_EXT_CAP_ID_VC Virtual Channel
368 * %PCI_EXT_CAP_ID_DSN Device Serial Number
369 * %PCI_EXT_CAP_ID_PWR Power Budgeting
370 */
371int pci_find_ext_capability(struct pci_dev *dev, int cap)
372{
373 return pci_find_next_ext_capability(dev, 0, cap);
374}
375EXPORT_SYMBOL_GPL(pci_find_ext_capability);
376
377static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
378{
379 int rc, ttl = PCI_FIND_CAP_TTL;
380 u8 cap, mask;
381
382 if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
383 mask = HT_3BIT_CAP_MASK;
384 else
385 mask = HT_5BIT_CAP_MASK;
386
387 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
388 PCI_CAP_ID_HT, &ttl);
389 while (pos) {
390 rc = pci_read_config_byte(dev, pos + 3, &cap);
391 if (rc != PCIBIOS_SUCCESSFUL)
392 return 0;
393
394 if ((cap & mask) == ht_cap)
395 return pos;
396
397 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
398 pos + PCI_CAP_LIST_NEXT,
399 PCI_CAP_ID_HT, &ttl);
400 }
401
402 return 0;
403}
404/**
405 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
406 * @dev: PCI device to query
407 * @pos: Position from which to continue searching
408 * @ht_cap: Hypertransport capability code
409 *
410 * To be used in conjunction with pci_find_ht_capability() to search for
411 * all capabilities matching @ht_cap. @pos should always be a value returned
412 * from pci_find_ht_capability().
413 *
414 * NB. To be 100% safe against broken PCI devices, the caller should take
415 * steps to avoid an infinite loop.
416 */
417int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
418{
419 return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
420}
421EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
422
423/**
424 * pci_find_ht_capability - query a device's Hypertransport capabilities
425 * @dev: PCI device to query
426 * @ht_cap: Hypertransport capability code
427 *
428 * Tell if a device supports a given Hypertransport capability.
429 * Returns an address within the device's PCI configuration space
430 * or 0 in case the device does not support the request capability.
431 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
432 * which has a Hypertransport capability matching @ht_cap.
433 */
434int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
435{
436 int pos;
437
438 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
439 if (pos)
440 pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
441
442 return pos;
443}
444EXPORT_SYMBOL_GPL(pci_find_ht_capability);
445
446/**
447 * pci_find_parent_resource - return resource region of parent bus of given region
448 * @dev: PCI device structure contains resources to be searched
449 * @res: child resource record for which parent is sought
450 *
451 * For given resource region of given device, return the resource
452 * region of parent bus the given region is contained in.
453 */
454struct resource *pci_find_parent_resource(const struct pci_dev *dev,
455 struct resource *res)
456{
457 const struct pci_bus *bus = dev->bus;
458 struct resource *r;
459 int i;
460
461 pci_bus_for_each_resource(bus, r, i) {
462 if (!r)
463 continue;
464 if (resource_contains(r, res)) {
465
466 /*
467 * If the window is prefetchable but the BAR is
468 * not, the allocator made a mistake.
469 */
470 if (r->flags & IORESOURCE_PREFETCH &&
471 !(res->flags & IORESOURCE_PREFETCH))
472 return NULL;
473
474 /*
475 * If we're below a transparent bridge, there may
476 * be both a positively-decoded aperture and a
477 * subtractively-decoded region that contain the BAR.
478 * We want the positively-decoded one, so this depends
479 * on pci_bus_for_each_resource() giving us those
480 * first.
481 */
482 return r;
483 }
484 }
485 return NULL;
486}
487EXPORT_SYMBOL(pci_find_parent_resource);
488
489/**
490 * pci_find_resource - Return matching PCI device resource
491 * @dev: PCI device to query
492 * @res: Resource to look for
493 *
494 * Goes over standard PCI resources (BARs) and checks if the given resource
495 * is partially or fully contained in any of them. In that case the
496 * matching resource is returned, %NULL otherwise.
497 */
498struct resource *pci_find_resource(struct pci_dev *dev, struct resource *res)
499{
500 int i;
501
502 for (i = 0; i < PCI_ROM_RESOURCE; i++) {
503 struct resource *r = &dev->resource[i];
504
505 if (r->start && resource_contains(r, res))
506 return r;
507 }
508
509 return NULL;
510}
511EXPORT_SYMBOL(pci_find_resource);
512
513/**
514 * pci_find_pcie_root_port - return PCIe Root Port
515 * @dev: PCI device to query
516 *
517 * Traverse up the parent chain and return the PCIe Root Port PCI Device
518 * for a given PCI Device.
519 */
520struct pci_dev *pci_find_pcie_root_port(struct pci_dev *dev)
521{
522 struct pci_dev *bridge, *highest_pcie_bridge = dev;
523
524 bridge = pci_upstream_bridge(dev);
525 while (bridge && pci_is_pcie(bridge)) {
526 highest_pcie_bridge = bridge;
527 bridge = pci_upstream_bridge(bridge);
528 }
529
530 if (pci_pcie_type(highest_pcie_bridge) != PCI_EXP_TYPE_ROOT_PORT)
531 return NULL;
532
533 return highest_pcie_bridge;
534}
535EXPORT_SYMBOL(pci_find_pcie_root_port);
536
537/**
538 * pci_wait_for_pending - wait for @mask bit(s) to clear in status word @pos
539 * @dev: the PCI device to operate on
540 * @pos: config space offset of status word
541 * @mask: mask of bit(s) to care about in status word
542 *
543 * Return 1 when mask bit(s) in status word clear, 0 otherwise.
544 */
545int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask)
546{
547 int i;
548
549 /* Wait for Transaction Pending bit clean */
550 for (i = 0; i < 4; i++) {
551 u16 status;
552 if (i)
553 msleep((1 << (i - 1)) * 100);
554
555 pci_read_config_word(dev, pos, &status);
556 if (!(status & mask))
557 return 1;
558 }
559
560 return 0;
561}
562
563/**
564 * pci_restore_bars - restore a device's BAR values (e.g. after wake-up)
565 * @dev: PCI device to have its BARs restored
566 *
567 * Restore the BAR values for a given device, so as to make it
568 * accessible by its driver.
569 */
570static void pci_restore_bars(struct pci_dev *dev)
571{
572 int i;
573
574 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
575 pci_update_resource(dev, i);
576}
577
578static const struct pci_platform_pm_ops *pci_platform_pm;
579
580int pci_set_platform_pm(const struct pci_platform_pm_ops *ops)
581{
582 if (!ops->is_manageable || !ops->set_state || !ops->get_state ||
583 !ops->choose_state || !ops->set_wakeup || !ops->need_resume)
584 return -EINVAL;
585 pci_platform_pm = ops;
586 return 0;
587}
588
589static inline bool platform_pci_power_manageable(struct pci_dev *dev)
590{
591 return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
592}
593
594static inline int platform_pci_set_power_state(struct pci_dev *dev,
595 pci_power_t t)
596{
597 return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
598}
599
600static inline pci_power_t platform_pci_get_power_state(struct pci_dev *dev)
601{
602 return pci_platform_pm ? pci_platform_pm->get_state(dev) : PCI_UNKNOWN;
603}
604
605static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
606{
607 return pci_platform_pm ?
608 pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
609}
610
611static inline int platform_pci_set_wakeup(struct pci_dev *dev, bool enable)
612{
613 return pci_platform_pm ?
614 pci_platform_pm->set_wakeup(dev, enable) : -ENODEV;
615}
616
617static inline bool platform_pci_need_resume(struct pci_dev *dev)
618{
619 return pci_platform_pm ? pci_platform_pm->need_resume(dev) : false;
620}
621
622/**
623 * pci_raw_set_power_state - Use PCI PM registers to set the power state of
624 * given PCI device
625 * @dev: PCI device to handle.
626 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
627 *
628 * RETURN VALUE:
629 * -EINVAL if the requested state is invalid.
630 * -EIO if device does not support PCI PM or its PM capabilities register has a
631 * wrong version, or device doesn't support the requested state.
632 * 0 if device already is in the requested state.
633 * 0 if device's power state has been successfully changed.
634 */
635static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
636{
637 u16 pmcsr;
638 bool need_restore = false;
639
640 /* Check if we're already there */
641 if (dev->current_state == state)
642 return 0;
643
644 if (!dev->pm_cap)
645 return -EIO;
646
647 if (state < PCI_D0 || state > PCI_D3hot)
648 return -EINVAL;
649
650 /* Validate current state:
651 * Can enter D0 from any state, but if we can only go deeper
652 * to sleep if we're already in a low power state
653 */
654 if (state != PCI_D0 && dev->current_state <= PCI_D3cold
655 && dev->current_state > state) {
656 pci_err(dev, "invalid power transition (from state %d to %d)\n",
657 dev->current_state, state);
658 return -EINVAL;
659 }
660
661 /* check if this device supports the desired state */
662 if ((state == PCI_D1 && !dev->d1_support)
663 || (state == PCI_D2 && !dev->d2_support))
664 return -EIO;
665
666 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
667
668 /* If we're (effectively) in D3, force entire word to 0.
669 * This doesn't affect PME_Status, disables PME_En, and
670 * sets PowerState to 0.
671 */
672 switch (dev->current_state) {
673 case PCI_D0:
674 case PCI_D1:
675 case PCI_D2:
676 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
677 pmcsr |= state;
678 break;
679 case PCI_D3hot:
680 case PCI_D3cold:
681 case PCI_UNKNOWN: /* Boot-up */
682 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
683 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
684 need_restore = true;
685 /* Fall-through: force to D0 */
686 default:
687 pmcsr = 0;
688 break;
689 }
690
691 /* enter specified state */
692 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
693
694 /* Mandatory power management transition delays */
695 /* see PCI PM 1.1 5.6.1 table 18 */
696 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
697 pci_dev_d3_sleep(dev);
698 else if (state == PCI_D2 || dev->current_state == PCI_D2)
699 udelay(PCI_PM_D2_DELAY);
700
701 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
702 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
703 if (dev->current_state != state && printk_ratelimit())
704 pci_info(dev, "Refused to change power state, currently in D%d\n",
705 dev->current_state);
706
707 /*
708 * According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
709 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
710 * from D3hot to D0 _may_ perform an internal reset, thereby
711 * going to "D0 Uninitialized" rather than "D0 Initialized".
712 * For example, at least some versions of the 3c905B and the
713 * 3c556B exhibit this behaviour.
714 *
715 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
716 * devices in a D3hot state at boot. Consequently, we need to
717 * restore at least the BARs so that the device will be
718 * accessible to its driver.
719 */
720 if (need_restore)
721 pci_restore_bars(dev);
722
723 if (dev->bus->self)
724 pcie_aspm_pm_state_change(dev->bus->self);
725
726 return 0;
727}
728
729/**
730 * pci_update_current_state - Read power state of given device and cache it
731 * @dev: PCI device to handle.
732 * @state: State to cache in case the device doesn't have the PM capability
733 *
734 * The power state is read from the PMCSR register, which however is
735 * inaccessible in D3cold. The platform firmware is therefore queried first
736 * to detect accessibility of the register. In case the platform firmware
737 * reports an incorrect state or the device isn't power manageable by the
738 * platform at all, we try to detect D3cold by testing accessibility of the
739 * vendor ID in config space.
740 */
741void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
742{
743 if (platform_pci_get_power_state(dev) == PCI_D3cold ||
744 !pci_device_is_present(dev)) {
745 dev->current_state = PCI_D3cold;
746 } else if (dev->pm_cap) {
747 u16 pmcsr;
748
749 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
750 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
751 } else {
752 dev->current_state = state;
753 }
754}
755
756/**
757 * pci_power_up - Put the given device into D0 forcibly
758 * @dev: PCI device to power up
759 */
760void pci_power_up(struct pci_dev *dev)
761{
762 if (platform_pci_power_manageable(dev))
763 platform_pci_set_power_state(dev, PCI_D0);
764
765 pci_raw_set_power_state(dev, PCI_D0);
766 pci_update_current_state(dev, PCI_D0);
767}
768
769/**
770 * pci_platform_power_transition - Use platform to change device power state
771 * @dev: PCI device to handle.
772 * @state: State to put the device into.
773 */
774static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
775{
776 int error;
777
778 if (platform_pci_power_manageable(dev)) {
779 error = platform_pci_set_power_state(dev, state);
780 if (!error)
781 pci_update_current_state(dev, state);
782 } else
783 error = -ENODEV;
784
785 if (error && !dev->pm_cap) /* Fall back to PCI_D0 */
786 dev->current_state = PCI_D0;
787
788 return error;
789}
790
791/**
792 * pci_wakeup - Wake up a PCI device
793 * @pci_dev: Device to handle.
794 * @ign: ignored parameter
795 */
796static int pci_wakeup(struct pci_dev *pci_dev, void *ign)
797{
798 pci_wakeup_event(pci_dev);
799 pm_request_resume(&pci_dev->dev);
800 return 0;
801}
802
803/**
804 * pci_wakeup_bus - Walk given bus and wake up devices on it
805 * @bus: Top bus of the subtree to walk.
806 */
807void pci_wakeup_bus(struct pci_bus *bus)
808{
809 if (bus)
810 pci_walk_bus(bus, pci_wakeup, NULL);
811}
812
813/**
814 * __pci_start_power_transition - Start power transition of a PCI device
815 * @dev: PCI device to handle.
816 * @state: State to put the device into.
817 */
818static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
819{
820 if (state == PCI_D0) {
821 pci_platform_power_transition(dev, PCI_D0);
822 /*
823 * Mandatory power management transition delays, see
824 * PCI Express Base Specification Revision 2.0 Section
825 * 6.6.1: Conventional Reset. Do not delay for
826 * devices powered on/off by corresponding bridge,
827 * because have already delayed for the bridge.
828 */
829 if (dev->runtime_d3cold) {
830 if (dev->d3cold_delay)
831 msleep(dev->d3cold_delay);
832 /*
833 * When powering on a bridge from D3cold, the
834 * whole hierarchy may be powered on into
835 * D0uninitialized state, resume them to give
836 * them a chance to suspend again
837 */
838 pci_wakeup_bus(dev->subordinate);
839 }
840 }
841}
842
843/**
844 * __pci_dev_set_current_state - Set current state of a PCI device
845 * @dev: Device to handle
846 * @data: pointer to state to be set
847 */
848static int __pci_dev_set_current_state(struct pci_dev *dev, void *data)
849{
850 pci_power_t state = *(pci_power_t *)data;
851
852 dev->current_state = state;
853 return 0;
854}
855
856/**
857 * pci_bus_set_current_state - Walk given bus and set current state of devices
858 * @bus: Top bus of the subtree to walk.
859 * @state: state to be set
860 */
861void pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
862{
863 if (bus)
864 pci_walk_bus(bus, __pci_dev_set_current_state, &state);
865}
866
867/**
868 * __pci_complete_power_transition - Complete power transition of a PCI device
869 * @dev: PCI device to handle.
870 * @state: State to put the device into.
871 *
872 * This function should not be called directly by device drivers.
873 */
874int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
875{
876 int ret;
877
878 if (state <= PCI_D0)
879 return -EINVAL;
880 ret = pci_platform_power_transition(dev, state);
881 /* Power off the bridge may power off the whole hierarchy */
882 if (!ret && state == PCI_D3cold)
883 pci_bus_set_current_state(dev->subordinate, PCI_D3cold);
884 return ret;
885}
886EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
887
888/**
889 * pci_set_power_state - Set the power state of a PCI device
890 * @dev: PCI device to handle.
891 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
892 *
893 * Transition a device to a new power state, using the platform firmware and/or
894 * the device's PCI PM registers.
895 *
896 * RETURN VALUE:
897 * -EINVAL if the requested state is invalid.
898 * -EIO if device does not support PCI PM or its PM capabilities register has a
899 * wrong version, or device doesn't support the requested state.
900 * 0 if the transition is to D1 or D2 but D1 and D2 are not supported.
901 * 0 if device already is in the requested state.
902 * 0 if the transition is to D3 but D3 is not supported.
903 * 0 if device's power state has been successfully changed.
904 */
905int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
906{
907 int error;
908
909 /* bound the state we're entering */
910 if (state > PCI_D3cold)
911 state = PCI_D3cold;
912 else if (state < PCI_D0)
913 state = PCI_D0;
914 else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
915 /*
916 * If the device or the parent bridge do not support PCI PM,
917 * ignore the request if we're doing anything other than putting
918 * it into D0 (which would only happen on boot).
919 */
920 return 0;
921
922 /* Check if we're already there */
923 if (dev->current_state == state)
924 return 0;
925
926 __pci_start_power_transition(dev, state);
927
928 /* This device is quirked not to be put into D3, so
929 don't put it in D3 */
930 if (state >= PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
931 return 0;
932
933 /*
934 * To put device in D3cold, we put device into D3hot in native
935 * way, then put device into D3cold with platform ops
936 */
937 error = pci_raw_set_power_state(dev, state > PCI_D3hot ?
938 PCI_D3hot : state);
939
940 if (!__pci_complete_power_transition(dev, state))
941 error = 0;
942
943 return error;
944}
945EXPORT_SYMBOL(pci_set_power_state);
946
947/**
948 * pci_choose_state - Choose the power state of a PCI device
949 * @dev: PCI device to be suspended
950 * @state: target sleep state for the whole system. This is the value
951 * that is passed to suspend() function.
952 *
953 * Returns PCI power state suitable for given device and given system
954 * message.
955 */
956
957pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
958{
959 pci_power_t ret;
960
961 if (!dev->pm_cap)
962 return PCI_D0;
963
964 ret = platform_pci_choose_state(dev);
965 if (ret != PCI_POWER_ERROR)
966 return ret;
967
968 switch (state.event) {
969 case PM_EVENT_ON:
970 return PCI_D0;
971 case PM_EVENT_FREEZE:
972 case PM_EVENT_PRETHAW:
973 /* REVISIT both freeze and pre-thaw "should" use D0 */
974 case PM_EVENT_SUSPEND:
975 case PM_EVENT_HIBERNATE:
976 return PCI_D3hot;
977 default:
978 pci_info(dev, "unrecognized suspend event %d\n",
979 state.event);
980 BUG();
981 }
982 return PCI_D0;
983}
984EXPORT_SYMBOL(pci_choose_state);
985
986#define PCI_EXP_SAVE_REGS 7
987
988static struct pci_cap_saved_state *_pci_find_saved_cap(struct pci_dev *pci_dev,
989 u16 cap, bool extended)
990{
991 struct pci_cap_saved_state *tmp;
992
993 hlist_for_each_entry(tmp, &pci_dev->saved_cap_space, next) {
994 if (tmp->cap.cap_extended == extended && tmp->cap.cap_nr == cap)
995 return tmp;
996 }
997 return NULL;
998}
999
1000struct pci_cap_saved_state *pci_find_saved_cap(struct pci_dev *dev, char cap)
1001{
1002 return _pci_find_saved_cap(dev, cap, false);
1003}
1004
1005struct pci_cap_saved_state *pci_find_saved_ext_cap(struct pci_dev *dev, u16 cap)
1006{
1007 return _pci_find_saved_cap(dev, cap, true);
1008}
1009
1010static int pci_save_pcie_state(struct pci_dev *dev)
1011{
1012 int i = 0;
1013 struct pci_cap_saved_state *save_state;
1014 u16 *cap;
1015
1016 if (!pci_is_pcie(dev))
1017 return 0;
1018
1019 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
1020 if (!save_state) {
1021 pci_err(dev, "buffer not found in %s\n", __func__);
1022 return -ENOMEM;
1023 }
1024
1025 cap = (u16 *)&save_state->cap.data[0];
1026 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &cap[i++]);
1027 pcie_capability_read_word(dev, PCI_EXP_LNKCTL, &cap[i++]);
1028 pcie_capability_read_word(dev, PCI_EXP_SLTCTL, &cap[i++]);
1029 pcie_capability_read_word(dev, PCI_EXP_RTCTL, &cap[i++]);
1030 pcie_capability_read_word(dev, PCI_EXP_DEVCTL2, &cap[i++]);
1031 pcie_capability_read_word(dev, PCI_EXP_LNKCTL2, &cap[i++]);
1032 pcie_capability_read_word(dev, PCI_EXP_SLTCTL2, &cap[i++]);
1033
1034 return 0;
1035}
1036
1037static void pci_restore_pcie_state(struct pci_dev *dev)
1038{
1039 int i = 0;
1040 struct pci_cap_saved_state *save_state;
1041 u16 *cap;
1042
1043 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
1044 if (!save_state)
1045 return;
1046
1047 cap = (u16 *)&save_state->cap.data[0];
1048 pcie_capability_write_word(dev, PCI_EXP_DEVCTL, cap[i++]);
1049 pcie_capability_write_word(dev, PCI_EXP_LNKCTL, cap[i++]);
1050 pcie_capability_write_word(dev, PCI_EXP_SLTCTL, cap[i++]);
1051 pcie_capability_write_word(dev, PCI_EXP_RTCTL, cap[i++]);
1052 pcie_capability_write_word(dev, PCI_EXP_DEVCTL2, cap[i++]);
1053 pcie_capability_write_word(dev, PCI_EXP_LNKCTL2, cap[i++]);
1054 pcie_capability_write_word(dev, PCI_EXP_SLTCTL2, cap[i++]);
1055}
1056
1057
1058static int pci_save_pcix_state(struct pci_dev *dev)
1059{
1060 int pos;
1061 struct pci_cap_saved_state *save_state;
1062
1063 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1064 if (!pos)
1065 return 0;
1066
1067 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
1068 if (!save_state) {
1069 pci_err(dev, "buffer not found in %s\n", __func__);
1070 return -ENOMEM;
1071 }
1072
1073 pci_read_config_word(dev, pos + PCI_X_CMD,
1074 (u16 *)save_state->cap.data);
1075
1076 return 0;
1077}
1078
1079static void pci_restore_pcix_state(struct pci_dev *dev)
1080{
1081 int i = 0, pos;
1082 struct pci_cap_saved_state *save_state;
1083 u16 *cap;
1084
1085 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
1086 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1087 if (!save_state || !pos)
1088 return;
1089 cap = (u16 *)&save_state->cap.data[0];
1090
1091 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
1092}
1093
1094
1095/**
1096 * pci_save_state - save the PCI configuration space of a device before suspending
1097 * @dev: - PCI device that we're dealing with
1098 */
1099int pci_save_state(struct pci_dev *dev)
1100{
1101 int i;
1102 /* XXX: 100% dword access ok here? */
1103 for (i = 0; i < 16; i++)
1104 pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
1105 dev->state_saved = true;
1106
1107 i = pci_save_pcie_state(dev);
1108 if (i != 0)
1109 return i;
1110
1111 i = pci_save_pcix_state(dev);
1112 if (i != 0)
1113 return i;
1114
1115 return pci_save_vc_state(dev);
1116}
1117EXPORT_SYMBOL(pci_save_state);
1118
1119static void pci_restore_config_dword(struct pci_dev *pdev, int offset,
1120 u32 saved_val, int retry)
1121{
1122 u32 val;
1123
1124 pci_read_config_dword(pdev, offset, &val);
1125 if (val == saved_val)
1126 return;
1127
1128 for (;;) {
1129 pci_dbg(pdev, "restoring config space at offset %#x (was %#x, writing %#x)\n",
1130 offset, val, saved_val);
1131 pci_write_config_dword(pdev, offset, saved_val);
1132 if (retry-- <= 0)
1133 return;
1134
1135 pci_read_config_dword(pdev, offset, &val);
1136 if (val == saved_val)
1137 return;
1138
1139 mdelay(1);
1140 }
1141}
1142
1143static void pci_restore_config_space_range(struct pci_dev *pdev,
1144 int start, int end, int retry)
1145{
1146 int index;
1147
1148 for (index = end; index >= start; index--)
1149 pci_restore_config_dword(pdev, 4 * index,
1150 pdev->saved_config_space[index],
1151 retry);
1152}
1153
1154static void pci_restore_config_space(struct pci_dev *pdev)
1155{
1156 if (pdev->hdr_type == PCI_HEADER_TYPE_NORMAL) {
1157 pci_restore_config_space_range(pdev, 10, 15, 0);
1158 /* Restore BARs before the command register. */
1159 pci_restore_config_space_range(pdev, 4, 9, 10);
1160 pci_restore_config_space_range(pdev, 0, 3, 0);
1161 } else {
1162 pci_restore_config_space_range(pdev, 0, 15, 0);
1163 }
1164}
1165
1166/**
1167 * pci_restore_state - Restore the saved state of a PCI device
1168 * @dev: - PCI device that we're dealing with
1169 */
1170void pci_restore_state(struct pci_dev *dev)
1171{
1172 if (!dev->state_saved)
1173 return;
1174
1175 /* PCI Express register must be restored first */
1176 pci_restore_pcie_state(dev);
1177 pci_restore_pasid_state(dev);
1178 pci_restore_pri_state(dev);
1179 pci_restore_ats_state(dev);
1180 pci_restore_vc_state(dev);
1181
1182 pci_cleanup_aer_error_status_regs(dev);
1183
1184 pci_restore_config_space(dev);
1185
1186 pci_restore_pcix_state(dev);
1187 pci_restore_msi_state(dev);
1188
1189 /* Restore ACS and IOV configuration state */
1190 pci_enable_acs(dev);
1191 pci_restore_iov_state(dev);
1192
1193 dev->state_saved = false;
1194}
1195EXPORT_SYMBOL(pci_restore_state);
1196
1197struct pci_saved_state {
1198 u32 config_space[16];
1199 struct pci_cap_saved_data cap[0];
1200};
1201
1202/**
1203 * pci_store_saved_state - Allocate and return an opaque struct containing
1204 * the device saved state.
1205 * @dev: PCI device that we're dealing with
1206 *
1207 * Return NULL if no state or error.
1208 */
1209struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev)
1210{
1211 struct pci_saved_state *state;
1212 struct pci_cap_saved_state *tmp;
1213 struct pci_cap_saved_data *cap;
1214 size_t size;
1215
1216 if (!dev->state_saved)
1217 return NULL;
1218
1219 size = sizeof(*state) + sizeof(struct pci_cap_saved_data);
1220
1221 hlist_for_each_entry(tmp, &dev->saved_cap_space, next)
1222 size += sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1223
1224 state = kzalloc(size, GFP_KERNEL);
1225 if (!state)
1226 return NULL;
1227
1228 memcpy(state->config_space, dev->saved_config_space,
1229 sizeof(state->config_space));
1230
1231 cap = state->cap;
1232 hlist_for_each_entry(tmp, &dev->saved_cap_space, next) {
1233 size_t len = sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1234 memcpy(cap, &tmp->cap, len);
1235 cap = (struct pci_cap_saved_data *)((u8 *)cap + len);
1236 }
1237 /* Empty cap_save terminates list */
1238
1239 return state;
1240}
1241EXPORT_SYMBOL_GPL(pci_store_saved_state);
1242
1243/**
1244 * pci_load_saved_state - Reload the provided save state into struct pci_dev.
1245 * @dev: PCI device that we're dealing with
1246 * @state: Saved state returned from pci_store_saved_state()
1247 */
1248int pci_load_saved_state(struct pci_dev *dev,
1249 struct pci_saved_state *state)
1250{
1251 struct pci_cap_saved_data *cap;
1252
1253 dev->state_saved = false;
1254
1255 if (!state)
1256 return 0;
1257
1258 memcpy(dev->saved_config_space, state->config_space,
1259 sizeof(state->config_space));
1260
1261 cap = state->cap;
1262 while (cap->size) {
1263 struct pci_cap_saved_state *tmp;
1264
1265 tmp = _pci_find_saved_cap(dev, cap->cap_nr, cap->cap_extended);
1266 if (!tmp || tmp->cap.size != cap->size)
1267 return -EINVAL;
1268
1269 memcpy(tmp->cap.data, cap->data, tmp->cap.size);
1270 cap = (struct pci_cap_saved_data *)((u8 *)cap +
1271 sizeof(struct pci_cap_saved_data) + cap->size);
1272 }
1273
1274 dev->state_saved = true;
1275 return 0;
1276}
1277EXPORT_SYMBOL_GPL(pci_load_saved_state);
1278
1279/**
1280 * pci_load_and_free_saved_state - Reload the save state pointed to by state,
1281 * and free the memory allocated for it.
1282 * @dev: PCI device that we're dealing with
1283 * @state: Pointer to saved state returned from pci_store_saved_state()
1284 */
1285int pci_load_and_free_saved_state(struct pci_dev *dev,
1286 struct pci_saved_state **state)
1287{
1288 int ret = pci_load_saved_state(dev, *state);
1289 kfree(*state);
1290 *state = NULL;
1291 return ret;
1292}
1293EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state);
1294
1295int __weak pcibios_enable_device(struct pci_dev *dev, int bars)
1296{
1297 return pci_enable_resources(dev, bars);
1298}
1299
1300static int do_pci_enable_device(struct pci_dev *dev, int bars)
1301{
1302 int err;
1303 struct pci_dev *bridge;
1304 u16 cmd;
1305 u8 pin;
1306
1307 err = pci_set_power_state(dev, PCI_D0);
1308 if (err < 0 && err != -EIO)
1309 return err;
1310
1311 bridge = pci_upstream_bridge(dev);
1312 if (bridge)
1313 pcie_aspm_powersave_config_link(bridge);
1314
1315 err = pcibios_enable_device(dev, bars);
1316 if (err < 0)
1317 return err;
1318 pci_fixup_device(pci_fixup_enable, dev);
1319
1320 if (dev->msi_enabled || dev->msix_enabled)
1321 return 0;
1322
1323 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1324 if (pin) {
1325 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1326 if (cmd & PCI_COMMAND_INTX_DISABLE)
1327 pci_write_config_word(dev, PCI_COMMAND,
1328 cmd & ~PCI_COMMAND_INTX_DISABLE);
1329 }
1330
1331 return 0;
1332}
1333
1334/**
1335 * pci_reenable_device - Resume abandoned device
1336 * @dev: PCI device to be resumed
1337 *
1338 * Note this function is a backend of pci_default_resume and is not supposed
1339 * to be called by normal code, write proper resume handler and use it instead.
1340 */
1341int pci_reenable_device(struct pci_dev *dev)
1342{
1343 if (pci_is_enabled(dev))
1344 return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
1345 return 0;
1346}
1347EXPORT_SYMBOL(pci_reenable_device);
1348
1349static void pci_enable_bridge(struct pci_dev *dev)
1350{
1351 struct pci_dev *bridge;
1352 int retval;
1353
1354 bridge = pci_upstream_bridge(dev);
1355 if (bridge)
1356 pci_enable_bridge(bridge);
1357
1358 if (pci_is_enabled(dev)) {
1359 if (!dev->is_busmaster)
1360 pci_set_master(dev);
1361 return;
1362 }
1363
1364 retval = pci_enable_device(dev);
1365 if (retval)
1366 pci_err(dev, "Error enabling bridge (%d), continuing\n",
1367 retval);
1368 pci_set_master(dev);
1369}
1370
1371static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags)
1372{
1373 struct pci_dev *bridge;
1374 int err;
1375 int i, bars = 0;
1376
1377 /*
1378 * Power state could be unknown at this point, either due to a fresh
1379 * boot or a device removal call. So get the current power state
1380 * so that things like MSI message writing will behave as expected
1381 * (e.g. if the device really is in D0 at enable time).
1382 */
1383 if (dev->pm_cap) {
1384 u16 pmcsr;
1385 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1386 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
1387 }
1388
1389 if (atomic_inc_return(&dev->enable_cnt) > 1)
1390 return 0; /* already enabled */
1391
1392 bridge = pci_upstream_bridge(dev);
1393 if (bridge)
1394 pci_enable_bridge(bridge);
1395
1396 /* only skip sriov related */
1397 for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1398 if (dev->resource[i].flags & flags)
1399 bars |= (1 << i);
1400 for (i = PCI_BRIDGE_RESOURCES; i < DEVICE_COUNT_RESOURCE; i++)
1401 if (dev->resource[i].flags & flags)
1402 bars |= (1 << i);
1403
1404 err = do_pci_enable_device(dev, bars);
1405 if (err < 0)
1406 atomic_dec(&dev->enable_cnt);
1407 return err;
1408}
1409
1410/**
1411 * pci_enable_device_io - Initialize a device for use with IO space
1412 * @dev: PCI device to be initialized
1413 *
1414 * Initialize device before it's used by a driver. Ask low-level code
1415 * to enable I/O resources. Wake up the device if it was suspended.
1416 * Beware, this function can fail.
1417 */
1418int pci_enable_device_io(struct pci_dev *dev)
1419{
1420 return pci_enable_device_flags(dev, IORESOURCE_IO);
1421}
1422EXPORT_SYMBOL(pci_enable_device_io);
1423
1424/**
1425 * pci_enable_device_mem - Initialize a device for use with Memory space
1426 * @dev: PCI device to be initialized
1427 *
1428 * Initialize device before it's used by a driver. Ask low-level code
1429 * to enable Memory resources. Wake up the device if it was suspended.
1430 * Beware, this function can fail.
1431 */
1432int pci_enable_device_mem(struct pci_dev *dev)
1433{
1434 return pci_enable_device_flags(dev, IORESOURCE_MEM);
1435}
1436EXPORT_SYMBOL(pci_enable_device_mem);
1437
1438/**
1439 * pci_enable_device - Initialize device before it's used by a driver.
1440 * @dev: PCI device to be initialized
1441 *
1442 * Initialize device before it's used by a driver. Ask low-level code
1443 * to enable I/O and memory. Wake up the device if it was suspended.
1444 * Beware, this function can fail.
1445 *
1446 * Note we don't actually enable the device many times if we call
1447 * this function repeatedly (we just increment the count).
1448 */
1449int pci_enable_device(struct pci_dev *dev)
1450{
1451 return pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
1452}
1453EXPORT_SYMBOL(pci_enable_device);
1454
1455/*
1456 * Managed PCI resources. This manages device on/off, intx/msi/msix
1457 * on/off and BAR regions. pci_dev itself records msi/msix status, so
1458 * there's no need to track it separately. pci_devres is initialized
1459 * when a device is enabled using managed PCI device enable interface.
1460 */
1461struct pci_devres {
1462 unsigned int enabled:1;
1463 unsigned int pinned:1;
1464 unsigned int orig_intx:1;
1465 unsigned int restore_intx:1;
1466 unsigned int mwi:1;
1467 u32 region_mask;
1468};
1469
1470static void pcim_release(struct device *gendev, void *res)
1471{
1472 struct pci_dev *dev = to_pci_dev(gendev);
1473 struct pci_devres *this = res;
1474 int i;
1475
1476 if (dev->msi_enabled)
1477 pci_disable_msi(dev);
1478 if (dev->msix_enabled)
1479 pci_disable_msix(dev);
1480
1481 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1482 if (this->region_mask & (1 << i))
1483 pci_release_region(dev, i);
1484
1485 if (this->mwi)
1486 pci_clear_mwi(dev);
1487
1488 if (this->restore_intx)
1489 pci_intx(dev, this->orig_intx);
1490
1491 if (this->enabled && !this->pinned)
1492 pci_disable_device(dev);
1493}
1494
1495static struct pci_devres *get_pci_dr(struct pci_dev *pdev)
1496{
1497 struct pci_devres *dr, *new_dr;
1498
1499 dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1500 if (dr)
1501 return dr;
1502
1503 new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1504 if (!new_dr)
1505 return NULL;
1506 return devres_get(&pdev->dev, new_dr, NULL, NULL);
1507}
1508
1509static struct pci_devres *find_pci_dr(struct pci_dev *pdev)
1510{
1511 if (pci_is_managed(pdev))
1512 return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1513 return NULL;
1514}
1515
1516/**
1517 * pcim_enable_device - Managed pci_enable_device()
1518 * @pdev: PCI device to be initialized
1519 *
1520 * Managed pci_enable_device().
1521 */
1522int pcim_enable_device(struct pci_dev *pdev)
1523{
1524 struct pci_devres *dr;
1525 int rc;
1526
1527 dr = get_pci_dr(pdev);
1528 if (unlikely(!dr))
1529 return -ENOMEM;
1530 if (dr->enabled)
1531 return 0;
1532
1533 rc = pci_enable_device(pdev);
1534 if (!rc) {
1535 pdev->is_managed = 1;
1536 dr->enabled = 1;
1537 }
1538 return rc;
1539}
1540EXPORT_SYMBOL(pcim_enable_device);
1541
1542/**
1543 * pcim_pin_device - Pin managed PCI device
1544 * @pdev: PCI device to pin
1545 *
1546 * Pin managed PCI device @pdev. Pinned device won't be disabled on
1547 * driver detach. @pdev must have been enabled with
1548 * pcim_enable_device().
1549 */
1550void pcim_pin_device(struct pci_dev *pdev)
1551{
1552 struct pci_devres *dr;
1553
1554 dr = find_pci_dr(pdev);
1555 WARN_ON(!dr || !dr->enabled);
1556 if (dr)
1557 dr->pinned = 1;
1558}
1559EXPORT_SYMBOL(pcim_pin_device);
1560
1561/*
1562 * pcibios_add_device - provide arch specific hooks when adding device dev
1563 * @dev: the PCI device being added
1564 *
1565 * Permits the platform to provide architecture specific functionality when
1566 * devices are added. This is the default implementation. Architecture
1567 * implementations can override this.
1568 */
1569int __weak pcibios_add_device(struct pci_dev *dev)
1570{
1571 return 0;
1572}
1573
1574/**
1575 * pcibios_release_device - provide arch specific hooks when releasing device dev
1576 * @dev: the PCI device being released
1577 *
1578 * Permits the platform to provide architecture specific functionality when
1579 * devices are released. This is the default implementation. Architecture
1580 * implementations can override this.
1581 */
1582void __weak pcibios_release_device(struct pci_dev *dev) {}
1583
1584/**
1585 * pcibios_disable_device - disable arch specific PCI resources for device dev
1586 * @dev: the PCI device to disable
1587 *
1588 * Disables architecture specific PCI resources for the device. This
1589 * is the default implementation. Architecture implementations can
1590 * override this.
1591 */
1592void __weak pcibios_disable_device(struct pci_dev *dev) {}
1593
1594/**
1595 * pcibios_penalize_isa_irq - penalize an ISA IRQ
1596 * @irq: ISA IRQ to penalize
1597 * @active: IRQ active or not
1598 *
1599 * Permits the platform to provide architecture-specific functionality when
1600 * penalizing ISA IRQs. This is the default implementation. Architecture
1601 * implementations can override this.
1602 */
1603void __weak pcibios_penalize_isa_irq(int irq, int active) {}
1604
1605static void do_pci_disable_device(struct pci_dev *dev)
1606{
1607 u16 pci_command;
1608
1609 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1610 if (pci_command & PCI_COMMAND_MASTER) {
1611 pci_command &= ~PCI_COMMAND_MASTER;
1612 pci_write_config_word(dev, PCI_COMMAND, pci_command);
1613 }
1614
1615 pcibios_disable_device(dev);
1616}
1617
1618/**
1619 * pci_disable_enabled_device - Disable device without updating enable_cnt
1620 * @dev: PCI device to disable
1621 *
1622 * NOTE: This function is a backend of PCI power management routines and is
1623 * not supposed to be called drivers.
1624 */
1625void pci_disable_enabled_device(struct pci_dev *dev)
1626{
1627 if (pci_is_enabled(dev))
1628 do_pci_disable_device(dev);
1629}
1630
1631/**
1632 * pci_disable_device - Disable PCI device after use
1633 * @dev: PCI device to be disabled
1634 *
1635 * Signal to the system that the PCI device is not in use by the system
1636 * anymore. This only involves disabling PCI bus-mastering, if active.
1637 *
1638 * Note we don't actually disable the device until all callers of
1639 * pci_enable_device() have called pci_disable_device().
1640 */
1641void pci_disable_device(struct pci_dev *dev)
1642{
1643 struct pci_devres *dr;
1644
1645 dr = find_pci_dr(dev);
1646 if (dr)
1647 dr->enabled = 0;
1648
1649 dev_WARN_ONCE(&dev->dev, atomic_read(&dev->enable_cnt) <= 0,
1650 "disabling already-disabled device");
1651
1652 if (atomic_dec_return(&dev->enable_cnt) != 0)
1653 return;
1654
1655 do_pci_disable_device(dev);
1656
1657 dev->is_busmaster = 0;
1658}
1659EXPORT_SYMBOL(pci_disable_device);
1660
1661/**
1662 * pcibios_set_pcie_reset_state - set reset state for device dev
1663 * @dev: the PCIe device reset
1664 * @state: Reset state to enter into
1665 *
1666 *
1667 * Sets the PCIe reset state for the device. This is the default
1668 * implementation. Architecture implementations can override this.
1669 */
1670int __weak pcibios_set_pcie_reset_state(struct pci_dev *dev,
1671 enum pcie_reset_state state)
1672{
1673 return -EINVAL;
1674}
1675
1676/**
1677 * pci_set_pcie_reset_state - set reset state for device dev
1678 * @dev: the PCIe device reset
1679 * @state: Reset state to enter into
1680 *
1681 *
1682 * Sets the PCI reset state for the device.
1683 */
1684int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1685{
1686 return pcibios_set_pcie_reset_state(dev, state);
1687}
1688EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
1689
1690/**
1691 * pcie_clear_root_pme_status - Clear root port PME interrupt status.
1692 * @dev: PCIe root port or event collector.
1693 */
1694void pcie_clear_root_pme_status(struct pci_dev *dev)
1695{
1696 pcie_capability_set_dword(dev, PCI_EXP_RTSTA, PCI_EXP_RTSTA_PME);
1697}
1698
1699/**
1700 * pci_check_pme_status - Check if given device has generated PME.
1701 * @dev: Device to check.
1702 *
1703 * Check the PME status of the device and if set, clear it and clear PME enable
1704 * (if set). Return 'true' if PME status and PME enable were both set or
1705 * 'false' otherwise.
1706 */
1707bool pci_check_pme_status(struct pci_dev *dev)
1708{
1709 int pmcsr_pos;
1710 u16 pmcsr;
1711 bool ret = false;
1712
1713 if (!dev->pm_cap)
1714 return false;
1715
1716 pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
1717 pci_read_config_word(dev, pmcsr_pos, &pmcsr);
1718 if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
1719 return false;
1720
1721 /* Clear PME status. */
1722 pmcsr |= PCI_PM_CTRL_PME_STATUS;
1723 if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
1724 /* Disable PME to avoid interrupt flood. */
1725 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1726 ret = true;
1727 }
1728
1729 pci_write_config_word(dev, pmcsr_pos, pmcsr);
1730
1731 return ret;
1732}
1733
1734/**
1735 * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
1736 * @dev: Device to handle.
1737 * @pme_poll_reset: Whether or not to reset the device's pme_poll flag.
1738 *
1739 * Check if @dev has generated PME and queue a resume request for it in that
1740 * case.
1741 */
1742static int pci_pme_wakeup(struct pci_dev *dev, void *pme_poll_reset)
1743{
1744 if (pme_poll_reset && dev->pme_poll)
1745 dev->pme_poll = false;
1746
1747 if (pci_check_pme_status(dev)) {
1748 pci_wakeup_event(dev);
1749 pm_request_resume(&dev->dev);
1750 }
1751 return 0;
1752}
1753
1754/**
1755 * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
1756 * @bus: Top bus of the subtree to walk.
1757 */
1758void pci_pme_wakeup_bus(struct pci_bus *bus)
1759{
1760 if (bus)
1761 pci_walk_bus(bus, pci_pme_wakeup, (void *)true);
1762}
1763
1764
1765/**
1766 * pci_pme_capable - check the capability of PCI device to generate PME#
1767 * @dev: PCI device to handle.
1768 * @state: PCI state from which device will issue PME#.
1769 */
1770bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1771{
1772 if (!dev->pm_cap)
1773 return false;
1774
1775 return !!(dev->pme_support & (1 << state));
1776}
1777EXPORT_SYMBOL(pci_pme_capable);
1778
1779static void pci_pme_list_scan(struct work_struct *work)
1780{
1781 struct pci_pme_device *pme_dev, *n;
1782
1783 mutex_lock(&pci_pme_list_mutex);
1784 list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) {
1785 if (pme_dev->dev->pme_poll) {
1786 struct pci_dev *bridge;
1787
1788 bridge = pme_dev->dev->bus->self;
1789 /*
1790 * If bridge is in low power state, the
1791 * configuration space of subordinate devices
1792 * may be not accessible
1793 */
1794 if (bridge && bridge->current_state != PCI_D0)
1795 continue;
1796 pci_pme_wakeup(pme_dev->dev, NULL);
1797 } else {
1798 list_del(&pme_dev->list);
1799 kfree(pme_dev);
1800 }
1801 }
1802 if (!list_empty(&pci_pme_list))
1803 queue_delayed_work(system_freezable_wq, &pci_pme_work,
1804 msecs_to_jiffies(PME_TIMEOUT));
1805 mutex_unlock(&pci_pme_list_mutex);
1806}
1807
1808static void __pci_pme_active(struct pci_dev *dev, bool enable)
1809{
1810 u16 pmcsr;
1811
1812 if (!dev->pme_support)
1813 return;
1814
1815 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1816 /* Clear PME_Status by writing 1 to it and enable PME# */
1817 pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1818 if (!enable)
1819 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1820
1821 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1822}
1823
1824/**
1825 * pci_pme_restore - Restore PME configuration after config space restore.
1826 * @dev: PCI device to update.
1827 */
1828void pci_pme_restore(struct pci_dev *dev)
1829{
1830 u16 pmcsr;
1831
1832 if (!dev->pme_support)
1833 return;
1834
1835 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1836 if (dev->wakeup_prepared) {
1837 pmcsr |= PCI_PM_CTRL_PME_ENABLE;
1838 pmcsr &= ~PCI_PM_CTRL_PME_STATUS;
1839 } else {
1840 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1841 pmcsr |= PCI_PM_CTRL_PME_STATUS;
1842 }
1843 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1844}
1845
1846/**
1847 * pci_pme_active - enable or disable PCI device's PME# function
1848 * @dev: PCI device to handle.
1849 * @enable: 'true' to enable PME# generation; 'false' to disable it.
1850 *
1851 * The caller must verify that the device is capable of generating PME# before
1852 * calling this function with @enable equal to 'true'.
1853 */
1854void pci_pme_active(struct pci_dev *dev, bool enable)
1855{
1856 __pci_pme_active(dev, enable);
1857
1858 /*
1859 * PCI (as opposed to PCIe) PME requires that the device have
1860 * its PME# line hooked up correctly. Not all hardware vendors
1861 * do this, so the PME never gets delivered and the device
1862 * remains asleep. The easiest way around this is to
1863 * periodically walk the list of suspended devices and check
1864 * whether any have their PME flag set. The assumption is that
1865 * we'll wake up often enough anyway that this won't be a huge
1866 * hit, and the power savings from the devices will still be a
1867 * win.
1868 *
1869 * Although PCIe uses in-band PME message instead of PME# line
1870 * to report PME, PME does not work for some PCIe devices in
1871 * reality. For example, there are devices that set their PME
1872 * status bits, but don't really bother to send a PME message;
1873 * there are PCI Express Root Ports that don't bother to
1874 * trigger interrupts when they receive PME messages from the
1875 * devices below. So PME poll is used for PCIe devices too.
1876 */
1877
1878 if (dev->pme_poll) {
1879 struct pci_pme_device *pme_dev;
1880 if (enable) {
1881 pme_dev = kmalloc(sizeof(struct pci_pme_device),
1882 GFP_KERNEL);
1883 if (!pme_dev) {
1884 pci_warn(dev, "can't enable PME#\n");
1885 return;
1886 }
1887 pme_dev->dev = dev;
1888 mutex_lock(&pci_pme_list_mutex);
1889 list_add(&pme_dev->list, &pci_pme_list);
1890 if (list_is_singular(&pci_pme_list))
1891 queue_delayed_work(system_freezable_wq,
1892 &pci_pme_work,
1893 msecs_to_jiffies(PME_TIMEOUT));
1894 mutex_unlock(&pci_pme_list_mutex);
1895 } else {
1896 mutex_lock(&pci_pme_list_mutex);
1897 list_for_each_entry(pme_dev, &pci_pme_list, list) {
1898 if (pme_dev->dev == dev) {
1899 list_del(&pme_dev->list);
1900 kfree(pme_dev);
1901 break;
1902 }
1903 }
1904 mutex_unlock(&pci_pme_list_mutex);
1905 }
1906 }
1907
1908 pci_dbg(dev, "PME# %s\n", enable ? "enabled" : "disabled");
1909}
1910EXPORT_SYMBOL(pci_pme_active);
1911
1912/**
1913 * __pci_enable_wake - enable PCI device as wakeup event source
1914 * @dev: PCI device affected
1915 * @state: PCI state from which device will issue wakeup events
1916 * @enable: True to enable event generation; false to disable
1917 *
1918 * This enables the device as a wakeup event source, or disables it.
1919 * When such events involves platform-specific hooks, those hooks are
1920 * called automatically by this routine.
1921 *
1922 * Devices with legacy power management (no standard PCI PM capabilities)
1923 * always require such platform hooks.
1924 *
1925 * RETURN VALUE:
1926 * 0 is returned on success
1927 * -EINVAL is returned if device is not supposed to wake up the system
1928 * Error code depending on the platform is returned if both the platform and
1929 * the native mechanism fail to enable the generation of wake-up events
1930 */
1931static int __pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool enable)
1932{
1933 int ret = 0;
1934
1935 /*
1936 * Bridges can only signal wakeup on behalf of subordinate devices,
1937 * but that is set up elsewhere, so skip them.
1938 */
1939 if (pci_has_subordinate(dev))
1940 return 0;
1941
1942 /* Don't do the same thing twice in a row for one device. */
1943 if (!!enable == !!dev->wakeup_prepared)
1944 return 0;
1945
1946 /*
1947 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1948 * Anderson we should be doing PME# wake enable followed by ACPI wake
1949 * enable. To disable wake-up we call the platform first, for symmetry.
1950 */
1951
1952 if (enable) {
1953 int error;
1954
1955 if (pci_pme_capable(dev, state))
1956 pci_pme_active(dev, true);
1957 else
1958 ret = 1;
1959 error = platform_pci_set_wakeup(dev, true);
1960 if (ret)
1961 ret = error;
1962 if (!ret)
1963 dev->wakeup_prepared = true;
1964 } else {
1965 platform_pci_set_wakeup(dev, false);
1966 pci_pme_active(dev, false);
1967 dev->wakeup_prepared = false;
1968 }
1969
1970 return ret;
1971}
1972
1973/**
1974 * pci_enable_wake - change wakeup settings for a PCI device
1975 * @pci_dev: Target device
1976 * @state: PCI state from which device will issue wakeup events
1977 * @enable: Whether or not to enable event generation
1978 *
1979 * If @enable is set, check device_may_wakeup() for the device before calling
1980 * __pci_enable_wake() for it.
1981 */
1982int pci_enable_wake(struct pci_dev *pci_dev, pci_power_t state, bool enable)
1983{
1984 if (enable && !device_may_wakeup(&pci_dev->dev))
1985 return -EINVAL;
1986
1987 return __pci_enable_wake(pci_dev, state, enable);
1988}
1989EXPORT_SYMBOL(pci_enable_wake);
1990
1991/**
1992 * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1993 * @dev: PCI device to prepare
1994 * @enable: True to enable wake-up event generation; false to disable
1995 *
1996 * Many drivers want the device to wake up the system from D3_hot or D3_cold
1997 * and this function allows them to set that up cleanly - pci_enable_wake()
1998 * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1999 * ordering constraints.
2000 *
2001 * This function only returns error code if the device is not allowed to wake
2002 * up the system from sleep or it is not capable of generating PME# from both
2003 * D3_hot and D3_cold and the platform is unable to enable wake-up power for it.
2004 */
2005int pci_wake_from_d3(struct pci_dev *dev, bool enable)
2006{
2007 return pci_pme_capable(dev, PCI_D3cold) ?
2008 pci_enable_wake(dev, PCI_D3cold, enable) :
2009 pci_enable_wake(dev, PCI_D3hot, enable);
2010}
2011EXPORT_SYMBOL(pci_wake_from_d3);
2012
2013/**
2014 * pci_target_state - find an appropriate low power state for a given PCI dev
2015 * @dev: PCI device
2016 * @wakeup: Whether or not wakeup functionality will be enabled for the device.
2017 *
2018 * Use underlying platform code to find a supported low power state for @dev.
2019 * If the platform can't manage @dev, return the deepest state from which it
2020 * can generate wake events, based on any available PME info.
2021 */
2022static pci_power_t pci_target_state(struct pci_dev *dev, bool wakeup)
2023{
2024 pci_power_t target_state = PCI_D3hot;
2025
2026 if (platform_pci_power_manageable(dev)) {
2027 /*
2028 * Call the platform to choose the target state of the device
2029 * and enable wake-up from this state if supported.
2030 */
2031 pci_power_t state = platform_pci_choose_state(dev);
2032
2033 switch (state) {
2034 case PCI_POWER_ERROR:
2035 case PCI_UNKNOWN:
2036 break;
2037 case PCI_D1:
2038 case PCI_D2:
2039 if (pci_no_d1d2(dev))
2040 break;
2041 default:
2042 target_state = state;
2043 }
2044
2045 return target_state;
2046 }
2047
2048 if (!dev->pm_cap)
2049 target_state = PCI_D0;
2050
2051 /*
2052 * If the device is in D3cold even though it's not power-manageable by
2053 * the platform, it may have been powered down by non-standard means.
2054 * Best to let it slumber.
2055 */
2056 if (dev->current_state == PCI_D3cold)
2057 target_state = PCI_D3cold;
2058
2059 if (wakeup) {
2060 /*
2061 * Find the deepest state from which the device can generate
2062 * wake-up events, make it the target state and enable device
2063 * to generate PME#.
2064 */
2065 if (dev->pme_support) {
2066 while (target_state
2067 && !(dev->pme_support & (1 << target_state)))
2068 target_state--;
2069 }
2070 }
2071
2072 return target_state;
2073}
2074
2075/**
2076 * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
2077 * @dev: Device to handle.
2078 *
2079 * Choose the power state appropriate for the device depending on whether
2080 * it can wake up the system and/or is power manageable by the platform
2081 * (PCI_D3hot is the default) and put the device into that state.
2082 */
2083int pci_prepare_to_sleep(struct pci_dev *dev)
2084{
2085 bool wakeup = device_may_wakeup(&dev->dev);
2086 pci_power_t target_state = pci_target_state(dev, wakeup);
2087 int error;
2088
2089 if (target_state == PCI_POWER_ERROR)
2090 return -EIO;
2091
2092 pci_enable_wake(dev, target_state, wakeup);
2093
2094 error = pci_set_power_state(dev, target_state);
2095
2096 if (error)
2097 pci_enable_wake(dev, target_state, false);
2098
2099 return error;
2100}
2101EXPORT_SYMBOL(pci_prepare_to_sleep);
2102
2103/**
2104 * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
2105 * @dev: Device to handle.
2106 *
2107 * Disable device's system wake-up capability and put it into D0.
2108 */
2109int pci_back_from_sleep(struct pci_dev *dev)
2110{
2111 pci_enable_wake(dev, PCI_D0, false);
2112 return pci_set_power_state(dev, PCI_D0);
2113}
2114EXPORT_SYMBOL(pci_back_from_sleep);
2115
2116/**
2117 * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend.
2118 * @dev: PCI device being suspended.
2119 *
2120 * Prepare @dev to generate wake-up events at run time and put it into a low
2121 * power state.
2122 */
2123int pci_finish_runtime_suspend(struct pci_dev *dev)
2124{
2125 pci_power_t target_state;
2126 int error;
2127
2128 target_state = pci_target_state(dev, device_can_wakeup(&dev->dev));
2129 if (target_state == PCI_POWER_ERROR)
2130 return -EIO;
2131
2132 dev->runtime_d3cold = target_state == PCI_D3cold;
2133
2134 __pci_enable_wake(dev, target_state, pci_dev_run_wake(dev));
2135
2136 error = pci_set_power_state(dev, target_state);
2137
2138 if (error) {
2139 pci_enable_wake(dev, target_state, false);
2140 dev->runtime_d3cold = false;
2141 }
2142
2143 return error;
2144}
2145
2146/**
2147 * pci_dev_run_wake - Check if device can generate run-time wake-up events.
2148 * @dev: Device to check.
2149 *
2150 * Return true if the device itself is capable of generating wake-up events
2151 * (through the platform or using the native PCIe PME) or if the device supports
2152 * PME and one of its upstream bridges can generate wake-up events.
2153 */
2154bool pci_dev_run_wake(struct pci_dev *dev)
2155{
2156 struct pci_bus *bus = dev->bus;
2157
2158 if (!dev->pme_support)
2159 return false;
2160
2161 /* PME-capable in principle, but not from the target power state */
2162 if (!pci_pme_capable(dev, pci_target_state(dev, true)))
2163 return false;
2164
2165 if (device_can_wakeup(&dev->dev))
2166 return true;
2167
2168 while (bus->parent) {
2169 struct pci_dev *bridge = bus->self;
2170
2171 if (device_can_wakeup(&bridge->dev))
2172 return true;
2173
2174 bus = bus->parent;
2175 }
2176
2177 /* We have reached the root bus. */
2178 if (bus->bridge)
2179 return device_can_wakeup(bus->bridge);
2180
2181 return false;
2182}
2183EXPORT_SYMBOL_GPL(pci_dev_run_wake);
2184
2185/**
2186 * pci_dev_keep_suspended - Check if the device can stay in the suspended state.
2187 * @pci_dev: Device to check.
2188 *
2189 * Return 'true' if the device is runtime-suspended, it doesn't have to be
2190 * reconfigured due to wakeup settings difference between system and runtime
2191 * suspend and the current power state of it is suitable for the upcoming
2192 * (system) transition.
2193 *
2194 * If the device is not configured for system wakeup, disable PME for it before
2195 * returning 'true' to prevent it from waking up the system unnecessarily.
2196 */
2197bool pci_dev_keep_suspended(struct pci_dev *pci_dev)
2198{
2199 struct device *dev = &pci_dev->dev;
2200 bool wakeup = device_may_wakeup(dev);
2201
2202 if (!pm_runtime_suspended(dev)
2203 || pci_target_state(pci_dev, wakeup) != pci_dev->current_state
2204 || platform_pci_need_resume(pci_dev))
2205 return false;
2206
2207 /*
2208 * At this point the device is good to go unless it's been configured
2209 * to generate PME at the runtime suspend time, but it is not supposed
2210 * to wake up the system. In that case, simply disable PME for it
2211 * (it will have to be re-enabled on exit from system resume).
2212 *
2213 * If the device's power state is D3cold and the platform check above
2214 * hasn't triggered, the device's configuration is suitable and we don't
2215 * need to manipulate it at all.
2216 */
2217 spin_lock_irq(&dev->power.lock);
2218
2219 if (pm_runtime_suspended(dev) && pci_dev->current_state < PCI_D3cold &&
2220 !wakeup)
2221 __pci_pme_active(pci_dev, false);
2222
2223 spin_unlock_irq(&dev->power.lock);
2224 return true;
2225}
2226
2227/**
2228 * pci_dev_complete_resume - Finalize resume from system sleep for a device.
2229 * @pci_dev: Device to handle.
2230 *
2231 * If the device is runtime suspended and wakeup-capable, enable PME for it as
2232 * it might have been disabled during the prepare phase of system suspend if
2233 * the device was not configured for system wakeup.
2234 */
2235void pci_dev_complete_resume(struct pci_dev *pci_dev)
2236{
2237 struct device *dev = &pci_dev->dev;
2238
2239 if (!pci_dev_run_wake(pci_dev))
2240 return;
2241
2242 spin_lock_irq(&dev->power.lock);
2243
2244 if (pm_runtime_suspended(dev) && pci_dev->current_state < PCI_D3cold)
2245 __pci_pme_active(pci_dev, true);
2246
2247 spin_unlock_irq(&dev->power.lock);
2248}
2249
2250void pci_config_pm_runtime_get(struct pci_dev *pdev)
2251{
2252 struct device *dev = &pdev->dev;
2253 struct device *parent = dev->parent;
2254
2255 if (parent)
2256 pm_runtime_get_sync(parent);
2257 pm_runtime_get_noresume(dev);
2258 /*
2259 * pdev->current_state is set to PCI_D3cold during suspending,
2260 * so wait until suspending completes
2261 */
2262 pm_runtime_barrier(dev);
2263 /*
2264 * Only need to resume devices in D3cold, because config
2265 * registers are still accessible for devices suspended but
2266 * not in D3cold.
2267 */
2268 if (pdev->current_state == PCI_D3cold)
2269 pm_runtime_resume(dev);
2270}
2271
2272void pci_config_pm_runtime_put(struct pci_dev *pdev)
2273{
2274 struct device *dev = &pdev->dev;
2275 struct device *parent = dev->parent;
2276
2277 pm_runtime_put(dev);
2278 if (parent)
2279 pm_runtime_put_sync(parent);
2280}
2281
2282/**
2283 * pci_bridge_d3_possible - Is it possible to put the bridge into D3
2284 * @bridge: Bridge to check
2285 *
2286 * This function checks if it is possible to move the bridge to D3.
2287 * Currently we only allow D3 for recent enough PCIe ports.
2288 */
2289bool pci_bridge_d3_possible(struct pci_dev *bridge)
2290{
2291 if (!pci_is_pcie(bridge))
2292 return false;
2293
2294 switch (pci_pcie_type(bridge)) {
2295 case PCI_EXP_TYPE_ROOT_PORT:
2296 case PCI_EXP_TYPE_UPSTREAM:
2297 case PCI_EXP_TYPE_DOWNSTREAM:
2298 if (pci_bridge_d3_disable)
2299 return false;
2300
2301 /*
2302 * Hotplug interrupts cannot be delivered if the link is down,
2303 * so parents of a hotplug port must stay awake. In addition,
2304 * hotplug ports handled by firmware in System Management Mode
2305 * may not be put into D3 by the OS (Thunderbolt on non-Macs).
2306 * For simplicity, disallow in general for now.
2307 */
2308 if (bridge->is_hotplug_bridge)
2309 return false;
2310
2311 if (pci_bridge_d3_force)
2312 return true;
2313
2314 /*
2315 * It should be safe to put PCIe ports from 2015 or newer
2316 * to D3.
2317 */
2318 if (dmi_get_bios_year() >= 2015)
2319 return true;
2320 break;
2321 }
2322
2323 return false;
2324}
2325
2326static int pci_dev_check_d3cold(struct pci_dev *dev, void *data)
2327{
2328 bool *d3cold_ok = data;
2329
2330 if (/* The device needs to be allowed to go D3cold ... */
2331 dev->no_d3cold || !dev->d3cold_allowed ||
2332
2333 /* ... and if it is wakeup capable to do so from D3cold. */
2334 (device_may_wakeup(&dev->dev) &&
2335 !pci_pme_capable(dev, PCI_D3cold)) ||
2336
2337 /* If it is a bridge it must be allowed to go to D3. */
2338 !pci_power_manageable(dev))
2339
2340 *d3cold_ok = false;
2341
2342 return !*d3cold_ok;
2343}
2344
2345/*
2346 * pci_bridge_d3_update - Update bridge D3 capabilities
2347 * @dev: PCI device which is changed
2348 *
2349 * Update upstream bridge PM capabilities accordingly depending on if the
2350 * device PM configuration was changed or the device is being removed. The
2351 * change is also propagated upstream.
2352 */
2353void pci_bridge_d3_update(struct pci_dev *dev)
2354{
2355 bool remove = !device_is_registered(&dev->dev);
2356 struct pci_dev *bridge;
2357 bool d3cold_ok = true;
2358
2359 bridge = pci_upstream_bridge(dev);
2360 if (!bridge || !pci_bridge_d3_possible(bridge))
2361 return;
2362
2363 /*
2364 * If D3 is currently allowed for the bridge, removing one of its
2365 * children won't change that.
2366 */
2367 if (remove && bridge->bridge_d3)
2368 return;
2369
2370 /*
2371 * If D3 is currently allowed for the bridge and a child is added or
2372 * changed, disallowance of D3 can only be caused by that child, so
2373 * we only need to check that single device, not any of its siblings.
2374 *
2375 * If D3 is currently not allowed for the bridge, checking the device
2376 * first may allow us to skip checking its siblings.
2377 */
2378 if (!remove)
2379 pci_dev_check_d3cold(dev, &d3cold_ok);
2380
2381 /*
2382 * If D3 is currently not allowed for the bridge, this may be caused
2383 * either by the device being changed/removed or any of its siblings,
2384 * so we need to go through all children to find out if one of them
2385 * continues to block D3.
2386 */
2387 if (d3cold_ok && !bridge->bridge_d3)
2388 pci_walk_bus(bridge->subordinate, pci_dev_check_d3cold,
2389 &d3cold_ok);
2390
2391 if (bridge->bridge_d3 != d3cold_ok) {
2392 bridge->bridge_d3 = d3cold_ok;
2393 /* Propagate change to upstream bridges */
2394 pci_bridge_d3_update(bridge);
2395 }
2396}
2397
2398/**
2399 * pci_d3cold_enable - Enable D3cold for device
2400 * @dev: PCI device to handle
2401 *
2402 * This function can be used in drivers to enable D3cold from the device
2403 * they handle. It also updates upstream PCI bridge PM capabilities
2404 * accordingly.
2405 */
2406void pci_d3cold_enable(struct pci_dev *dev)
2407{
2408 if (dev->no_d3cold) {
2409 dev->no_d3cold = false;
2410 pci_bridge_d3_update(dev);
2411 }
2412}
2413EXPORT_SYMBOL_GPL(pci_d3cold_enable);
2414
2415/**
2416 * pci_d3cold_disable - Disable D3cold for device
2417 * @dev: PCI device to handle
2418 *
2419 * This function can be used in drivers to disable D3cold from the device
2420 * they handle. It also updates upstream PCI bridge PM capabilities
2421 * accordingly.
2422 */
2423void pci_d3cold_disable(struct pci_dev *dev)
2424{
2425 if (!dev->no_d3cold) {
2426 dev->no_d3cold = true;
2427 pci_bridge_d3_update(dev);
2428 }
2429}
2430EXPORT_SYMBOL_GPL(pci_d3cold_disable);
2431
2432/**
2433 * pci_pm_init - Initialize PM functions of given PCI device
2434 * @dev: PCI device to handle.
2435 */
2436void pci_pm_init(struct pci_dev *dev)
2437{
2438 int pm;
2439 u16 pmc;
2440
2441 pm_runtime_forbid(&dev->dev);
2442 pm_runtime_set_active(&dev->dev);
2443 pm_runtime_enable(&dev->dev);
2444 device_enable_async_suspend(&dev->dev);
2445 dev->wakeup_prepared = false;
2446
2447 dev->pm_cap = 0;
2448 dev->pme_support = 0;
2449
2450 /* find PCI PM capability in list */
2451 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
2452 if (!pm)
2453 return;
2454 /* Check device's ability to generate PME# */
2455 pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
2456
2457 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
2458 pci_err(dev, "unsupported PM cap regs version (%u)\n",
2459 pmc & PCI_PM_CAP_VER_MASK);
2460 return;
2461 }
2462
2463 dev->pm_cap = pm;
2464 dev->d3_delay = PCI_PM_D3_WAIT;
2465 dev->d3cold_delay = PCI_PM_D3COLD_WAIT;
2466 dev->bridge_d3 = pci_bridge_d3_possible(dev);
2467 dev->d3cold_allowed = true;
2468
2469 dev->d1_support = false;
2470 dev->d2_support = false;
2471 if (!pci_no_d1d2(dev)) {
2472 if (pmc & PCI_PM_CAP_D1)
2473 dev->d1_support = true;
2474 if (pmc & PCI_PM_CAP_D2)
2475 dev->d2_support = true;
2476
2477 if (dev->d1_support || dev->d2_support)
2478 pci_printk(KERN_DEBUG, dev, "supports%s%s\n",
2479 dev->d1_support ? " D1" : "",
2480 dev->d2_support ? " D2" : "");
2481 }
2482
2483 pmc &= PCI_PM_CAP_PME_MASK;
2484 if (pmc) {
2485 pci_printk(KERN_DEBUG, dev, "PME# supported from%s%s%s%s%s\n",
2486 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
2487 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
2488 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
2489 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
2490 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
2491 dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
2492 dev->pme_poll = true;
2493 /*
2494 * Make device's PM flags reflect the wake-up capability, but
2495 * let the user space enable it to wake up the system as needed.
2496 */
2497 device_set_wakeup_capable(&dev->dev, true);
2498 /* Disable the PME# generation functionality */
2499 pci_pme_active(dev, false);
2500 }
2501}
2502
2503static unsigned long pci_ea_flags(struct pci_dev *dev, u8 prop)
2504{
2505 unsigned long flags = IORESOURCE_PCI_FIXED | IORESOURCE_PCI_EA_BEI;
2506
2507 switch (prop) {
2508 case PCI_EA_P_MEM:
2509 case PCI_EA_P_VF_MEM:
2510 flags |= IORESOURCE_MEM;
2511 break;
2512 case PCI_EA_P_MEM_PREFETCH:
2513 case PCI_EA_P_VF_MEM_PREFETCH:
2514 flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
2515 break;
2516 case PCI_EA_P_IO:
2517 flags |= IORESOURCE_IO;
2518 break;
2519 default:
2520 return 0;
2521 }
2522
2523 return flags;
2524}
2525
2526static struct resource *pci_ea_get_resource(struct pci_dev *dev, u8 bei,
2527 u8 prop)
2528{
2529 if (bei <= PCI_EA_BEI_BAR5 && prop <= PCI_EA_P_IO)
2530 return &dev->resource[bei];
2531#ifdef CONFIG_PCI_IOV
2532 else if (bei >= PCI_EA_BEI_VF_BAR0 && bei <= PCI_EA_BEI_VF_BAR5 &&
2533 (prop == PCI_EA_P_VF_MEM || prop == PCI_EA_P_VF_MEM_PREFETCH))
2534 return &dev->resource[PCI_IOV_RESOURCES +
2535 bei - PCI_EA_BEI_VF_BAR0];
2536#endif
2537 else if (bei == PCI_EA_BEI_ROM)
2538 return &dev->resource[PCI_ROM_RESOURCE];
2539 else
2540 return NULL;
2541}
2542
2543/* Read an Enhanced Allocation (EA) entry */
2544static int pci_ea_read(struct pci_dev *dev, int offset)
2545{
2546 struct resource *res;
2547 int ent_size, ent_offset = offset;
2548 resource_size_t start, end;
2549 unsigned long flags;
2550 u32 dw0, bei, base, max_offset;
2551 u8 prop;
2552 bool support_64 = (sizeof(resource_size_t) >= 8);
2553
2554 pci_read_config_dword(dev, ent_offset, &dw0);
2555 ent_offset += 4;
2556
2557 /* Entry size field indicates DWORDs after 1st */
2558 ent_size = ((dw0 & PCI_EA_ES) + 1) << 2;
2559
2560 if (!(dw0 & PCI_EA_ENABLE)) /* Entry not enabled */
2561 goto out;
2562
2563 bei = (dw0 & PCI_EA_BEI) >> 4;
2564 prop = (dw0 & PCI_EA_PP) >> 8;
2565
2566 /*
2567 * If the Property is in the reserved range, try the Secondary
2568 * Property instead.
2569 */
2570 if (prop > PCI_EA_P_BRIDGE_IO && prop < PCI_EA_P_MEM_RESERVED)
2571 prop = (dw0 & PCI_EA_SP) >> 16;
2572 if (prop > PCI_EA_P_BRIDGE_IO)
2573 goto out;
2574
2575 res = pci_ea_get_resource(dev, bei, prop);
2576 if (!res) {
2577 pci_err(dev, "Unsupported EA entry BEI: %u\n", bei);
2578 goto out;
2579 }
2580
2581 flags = pci_ea_flags(dev, prop);
2582 if (!flags) {
2583 pci_err(dev, "Unsupported EA properties: %#x\n", prop);
2584 goto out;
2585 }
2586
2587 /* Read Base */
2588 pci_read_config_dword(dev, ent_offset, &base);
2589 start = (base & PCI_EA_FIELD_MASK);
2590 ent_offset += 4;
2591
2592 /* Read MaxOffset */
2593 pci_read_config_dword(dev, ent_offset, &max_offset);
2594 ent_offset += 4;
2595
2596 /* Read Base MSBs (if 64-bit entry) */
2597 if (base & PCI_EA_IS_64) {
2598 u32 base_upper;
2599
2600 pci_read_config_dword(dev, ent_offset, &base_upper);
2601 ent_offset += 4;
2602
2603 flags |= IORESOURCE_MEM_64;
2604
2605 /* entry starts above 32-bit boundary, can't use */
2606 if (!support_64 && base_upper)
2607 goto out;
2608
2609 if (support_64)
2610 start |= ((u64)base_upper << 32);
2611 }
2612
2613 end = start + (max_offset | 0x03);
2614
2615 /* Read MaxOffset MSBs (if 64-bit entry) */
2616 if (max_offset & PCI_EA_IS_64) {
2617 u32 max_offset_upper;
2618
2619 pci_read_config_dword(dev, ent_offset, &max_offset_upper);
2620 ent_offset += 4;
2621
2622 flags |= IORESOURCE_MEM_64;
2623
2624 /* entry too big, can't use */
2625 if (!support_64 && max_offset_upper)
2626 goto out;
2627
2628 if (support_64)
2629 end += ((u64)max_offset_upper << 32);
2630 }
2631
2632 if (end < start) {
2633 pci_err(dev, "EA Entry crosses address boundary\n");
2634 goto out;
2635 }
2636
2637 if (ent_size != ent_offset - offset) {
2638 pci_err(dev, "EA Entry Size (%d) does not match length read (%d)\n",
2639 ent_size, ent_offset - offset);
2640 goto out;
2641 }
2642
2643 res->name = pci_name(dev);
2644 res->start = start;
2645 res->end = end;
2646 res->flags = flags;
2647
2648 if (bei <= PCI_EA_BEI_BAR5)
2649 pci_printk(KERN_DEBUG, dev, "BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
2650 bei, res, prop);
2651 else if (bei == PCI_EA_BEI_ROM)
2652 pci_printk(KERN_DEBUG, dev, "ROM: %pR (from Enhanced Allocation, properties %#02x)\n",
2653 res, prop);
2654 else if (bei >= PCI_EA_BEI_VF_BAR0 && bei <= PCI_EA_BEI_VF_BAR5)
2655 pci_printk(KERN_DEBUG, dev, "VF BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
2656 bei - PCI_EA_BEI_VF_BAR0, res, prop);
2657 else
2658 pci_printk(KERN_DEBUG, dev, "BEI %d res: %pR (from Enhanced Allocation, properties %#02x)\n",
2659 bei, res, prop);
2660
2661out:
2662 return offset + ent_size;
2663}
2664
2665/* Enhanced Allocation Initialization */
2666void pci_ea_init(struct pci_dev *dev)
2667{
2668 int ea;
2669 u8 num_ent;
2670 int offset;
2671 int i;
2672
2673 /* find PCI EA capability in list */
2674 ea = pci_find_capability(dev, PCI_CAP_ID_EA);
2675 if (!ea)
2676 return;
2677
2678 /* determine the number of entries */
2679 pci_bus_read_config_byte(dev->bus, dev->devfn, ea + PCI_EA_NUM_ENT,
2680 &num_ent);
2681 num_ent &= PCI_EA_NUM_ENT_MASK;
2682
2683 offset = ea + PCI_EA_FIRST_ENT;
2684
2685 /* Skip DWORD 2 for type 1 functions */
2686 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
2687 offset += 4;
2688
2689 /* parse each EA entry */
2690 for (i = 0; i < num_ent; ++i)
2691 offset = pci_ea_read(dev, offset);
2692}
2693
2694static void pci_add_saved_cap(struct pci_dev *pci_dev,
2695 struct pci_cap_saved_state *new_cap)
2696{
2697 hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space);
2698}
2699
2700/**
2701 * _pci_add_cap_save_buffer - allocate buffer for saving given
2702 * capability registers
2703 * @dev: the PCI device
2704 * @cap: the capability to allocate the buffer for
2705 * @extended: Standard or Extended capability ID
2706 * @size: requested size of the buffer
2707 */
2708static int _pci_add_cap_save_buffer(struct pci_dev *dev, u16 cap,
2709 bool extended, unsigned int size)
2710{
2711 int pos;
2712 struct pci_cap_saved_state *save_state;
2713
2714 if (extended)
2715 pos = pci_find_ext_capability(dev, cap);
2716 else
2717 pos = pci_find_capability(dev, cap);
2718
2719 if (!pos)
2720 return 0;
2721
2722 save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
2723 if (!save_state)
2724 return -ENOMEM;
2725
2726 save_state->cap.cap_nr = cap;
2727 save_state->cap.cap_extended = extended;
2728 save_state->cap.size = size;
2729 pci_add_saved_cap(dev, save_state);
2730
2731 return 0;
2732}
2733
2734int pci_add_cap_save_buffer(struct pci_dev *dev, char cap, unsigned int size)
2735{
2736 return _pci_add_cap_save_buffer(dev, cap, false, size);
2737}
2738
2739int pci_add_ext_cap_save_buffer(struct pci_dev *dev, u16 cap, unsigned int size)
2740{
2741 return _pci_add_cap_save_buffer(dev, cap, true, size);
2742}
2743
2744/**
2745 * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
2746 * @dev: the PCI device
2747 */
2748void pci_allocate_cap_save_buffers(struct pci_dev *dev)
2749{
2750 int error;
2751
2752 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
2753 PCI_EXP_SAVE_REGS * sizeof(u16));
2754 if (error)
2755 pci_err(dev, "unable to preallocate PCI Express save buffer\n");
2756
2757 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
2758 if (error)
2759 pci_err(dev, "unable to preallocate PCI-X save buffer\n");
2760
2761 pci_allocate_vc_save_buffers(dev);
2762}
2763
2764void pci_free_cap_save_buffers(struct pci_dev *dev)
2765{
2766 struct pci_cap_saved_state *tmp;
2767 struct hlist_node *n;
2768
2769 hlist_for_each_entry_safe(tmp, n, &dev->saved_cap_space, next)
2770 kfree(tmp);
2771}
2772
2773/**
2774 * pci_configure_ari - enable or disable ARI forwarding
2775 * @dev: the PCI device
2776 *
2777 * If @dev and its upstream bridge both support ARI, enable ARI in the
2778 * bridge. Otherwise, disable ARI in the bridge.
2779 */
2780void pci_configure_ari(struct pci_dev *dev)
2781{
2782 u32 cap;
2783 struct pci_dev *bridge;
2784
2785 if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn)
2786 return;
2787
2788 bridge = dev->bus->self;
2789 if (!bridge)
2790 return;
2791
2792 pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap);
2793 if (!(cap & PCI_EXP_DEVCAP2_ARI))
2794 return;
2795
2796 if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) {
2797 pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2,
2798 PCI_EXP_DEVCTL2_ARI);
2799 bridge->ari_enabled = 1;
2800 } else {
2801 pcie_capability_clear_word(bridge, PCI_EXP_DEVCTL2,
2802 PCI_EXP_DEVCTL2_ARI);
2803 bridge->ari_enabled = 0;
2804 }
2805}
2806
2807static int pci_acs_enable;
2808
2809/**
2810 * pci_request_acs - ask for ACS to be enabled if supported
2811 */
2812void pci_request_acs(void)
2813{
2814 pci_acs_enable = 1;
2815}
2816
2817/**
2818 * pci_std_enable_acs - enable ACS on devices using standard ACS capabilites
2819 * @dev: the PCI device
2820 */
2821static void pci_std_enable_acs(struct pci_dev *dev)
2822{
2823 int pos;
2824 u16 cap;
2825 u16 ctrl;
2826
2827 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
2828 if (!pos)
2829 return;
2830
2831 pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
2832 pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
2833
2834 /* Source Validation */
2835 ctrl |= (cap & PCI_ACS_SV);
2836
2837 /* P2P Request Redirect */
2838 ctrl |= (cap & PCI_ACS_RR);
2839
2840 /* P2P Completion Redirect */
2841 ctrl |= (cap & PCI_ACS_CR);
2842
2843 /* Upstream Forwarding */
2844 ctrl |= (cap & PCI_ACS_UF);
2845
2846 pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
2847}
2848
2849/**
2850 * pci_enable_acs - enable ACS if hardware support it
2851 * @dev: the PCI device
2852 */
2853void pci_enable_acs(struct pci_dev *dev)
2854{
2855 if (!pci_acs_enable)
2856 return;
2857
2858 if (!pci_dev_specific_enable_acs(dev))
2859 return;
2860
2861 pci_std_enable_acs(dev);
2862}
2863
2864static bool pci_acs_flags_enabled(struct pci_dev *pdev, u16 acs_flags)
2865{
2866 int pos;
2867 u16 cap, ctrl;
2868
2869 pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ACS);
2870 if (!pos)
2871 return false;
2872
2873 /*
2874 * Except for egress control, capabilities are either required
2875 * or only required if controllable. Features missing from the
2876 * capability field can therefore be assumed as hard-wired enabled.
2877 */
2878 pci_read_config_word(pdev, pos + PCI_ACS_CAP, &cap);
2879 acs_flags &= (cap | PCI_ACS_EC);
2880
2881 pci_read_config_word(pdev, pos + PCI_ACS_CTRL, &ctrl);
2882 return (ctrl & acs_flags) == acs_flags;
2883}
2884
2885/**
2886 * pci_acs_enabled - test ACS against required flags for a given device
2887 * @pdev: device to test
2888 * @acs_flags: required PCI ACS flags
2889 *
2890 * Return true if the device supports the provided flags. Automatically
2891 * filters out flags that are not implemented on multifunction devices.
2892 *
2893 * Note that this interface checks the effective ACS capabilities of the
2894 * device rather than the actual capabilities. For instance, most single
2895 * function endpoints are not required to support ACS because they have no
2896 * opportunity for peer-to-peer access. We therefore return 'true'
2897 * regardless of whether the device exposes an ACS capability. This makes
2898 * it much easier for callers of this function to ignore the actual type
2899 * or topology of the device when testing ACS support.
2900 */
2901bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags)
2902{
2903 int ret;
2904
2905 ret = pci_dev_specific_acs_enabled(pdev, acs_flags);
2906 if (ret >= 0)
2907 return ret > 0;
2908
2909 /*
2910 * Conventional PCI and PCI-X devices never support ACS, either
2911 * effectively or actually. The shared bus topology implies that
2912 * any device on the bus can receive or snoop DMA.
2913 */
2914 if (!pci_is_pcie(pdev))
2915 return false;
2916
2917 switch (pci_pcie_type(pdev)) {
2918 /*
2919 * PCI/X-to-PCIe bridges are not specifically mentioned by the spec,
2920 * but since their primary interface is PCI/X, we conservatively
2921 * handle them as we would a non-PCIe device.
2922 */
2923 case PCI_EXP_TYPE_PCIE_BRIDGE:
2924 /*
2925 * PCIe 3.0, 6.12.1 excludes ACS on these devices. "ACS is never
2926 * applicable... must never implement an ACS Extended Capability...".
2927 * This seems arbitrary, but we take a conservative interpretation
2928 * of this statement.
2929 */
2930 case PCI_EXP_TYPE_PCI_BRIDGE:
2931 case PCI_EXP_TYPE_RC_EC:
2932 return false;
2933 /*
2934 * PCIe 3.0, 6.12.1.1 specifies that downstream and root ports should
2935 * implement ACS in order to indicate their peer-to-peer capabilities,
2936 * regardless of whether they are single- or multi-function devices.
2937 */
2938 case PCI_EXP_TYPE_DOWNSTREAM:
2939 case PCI_EXP_TYPE_ROOT_PORT:
2940 return pci_acs_flags_enabled(pdev, acs_flags);
2941 /*
2942 * PCIe 3.0, 6.12.1.2 specifies ACS capabilities that should be
2943 * implemented by the remaining PCIe types to indicate peer-to-peer
2944 * capabilities, but only when they are part of a multifunction
2945 * device. The footnote for section 6.12 indicates the specific
2946 * PCIe types included here.
2947 */
2948 case PCI_EXP_TYPE_ENDPOINT:
2949 case PCI_EXP_TYPE_UPSTREAM:
2950 case PCI_EXP_TYPE_LEG_END:
2951 case PCI_EXP_TYPE_RC_END:
2952 if (!pdev->multifunction)
2953 break;
2954
2955 return pci_acs_flags_enabled(pdev, acs_flags);
2956 }
2957
2958 /*
2959 * PCIe 3.0, 6.12.1.3 specifies no ACS capabilities are applicable
2960 * to single function devices with the exception of downstream ports.
2961 */
2962 return true;
2963}
2964
2965/**
2966 * pci_acs_path_enable - test ACS flags from start to end in a hierarchy
2967 * @start: starting downstream device
2968 * @end: ending upstream device or NULL to search to the root bus
2969 * @acs_flags: required flags
2970 *
2971 * Walk up a device tree from start to end testing PCI ACS support. If
2972 * any step along the way does not support the required flags, return false.
2973 */
2974bool pci_acs_path_enabled(struct pci_dev *start,
2975 struct pci_dev *end, u16 acs_flags)
2976{
2977 struct pci_dev *pdev, *parent = start;
2978
2979 do {
2980 pdev = parent;
2981
2982 if (!pci_acs_enabled(pdev, acs_flags))
2983 return false;
2984
2985 if (pci_is_root_bus(pdev->bus))
2986 return (end == NULL);
2987
2988 parent = pdev->bus->self;
2989 } while (pdev != end);
2990
2991 return true;
2992}
2993
2994/**
2995 * pci_rebar_find_pos - find position of resize ctrl reg for BAR
2996 * @pdev: PCI device
2997 * @bar: BAR to find
2998 *
2999 * Helper to find the position of the ctrl register for a BAR.
3000 * Returns -ENOTSUPP if resizable BARs are not supported at all.
3001 * Returns -ENOENT if no ctrl register for the BAR could be found.
3002 */
3003static int pci_rebar_find_pos(struct pci_dev *pdev, int bar)
3004{
3005 unsigned int pos, nbars, i;
3006 u32 ctrl;
3007
3008 pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_REBAR);
3009 if (!pos)
3010 return -ENOTSUPP;
3011
3012 pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
3013 nbars = (ctrl & PCI_REBAR_CTRL_NBAR_MASK) >>
3014 PCI_REBAR_CTRL_NBAR_SHIFT;
3015
3016 for (i = 0; i < nbars; i++, pos += 8) {
3017 int bar_idx;
3018
3019 pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
3020 bar_idx = ctrl & PCI_REBAR_CTRL_BAR_IDX;
3021 if (bar_idx == bar)
3022 return pos;
3023 }
3024
3025 return -ENOENT;
3026}
3027
3028/**
3029 * pci_rebar_get_possible_sizes - get possible sizes for BAR
3030 * @pdev: PCI device
3031 * @bar: BAR to query
3032 *
3033 * Get the possible sizes of a resizable BAR as bitmask defined in the spec
3034 * (bit 0=1MB, bit 19=512GB). Returns 0 if BAR isn't resizable.
3035 */
3036u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar)
3037{
3038 int pos;
3039 u32 cap;
3040
3041 pos = pci_rebar_find_pos(pdev, bar);
3042 if (pos < 0)
3043 return 0;
3044
3045 pci_read_config_dword(pdev, pos + PCI_REBAR_CAP, &cap);
3046 return (cap & PCI_REBAR_CAP_SIZES) >> 4;
3047}
3048
3049/**
3050 * pci_rebar_get_current_size - get the current size of a BAR
3051 * @pdev: PCI device
3052 * @bar: BAR to set size to
3053 *
3054 * Read the size of a BAR from the resizable BAR config.
3055 * Returns size if found or negative error code.
3056 */
3057int pci_rebar_get_current_size(struct pci_dev *pdev, int bar)
3058{
3059 int pos;
3060 u32 ctrl;
3061
3062 pos = pci_rebar_find_pos(pdev, bar);
3063 if (pos < 0)
3064 return pos;
3065
3066 pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
3067 return (ctrl & PCI_REBAR_CTRL_BAR_SIZE) >> 8;
3068}
3069
3070/**
3071 * pci_rebar_set_size - set a new size for a BAR
3072 * @pdev: PCI device
3073 * @bar: BAR to set size to
3074 * @size: new size as defined in the spec (0=1MB, 19=512GB)
3075 *
3076 * Set the new size of a BAR as defined in the spec.
3077 * Returns zero if resizing was successful, error code otherwise.
3078 */
3079int pci_rebar_set_size(struct pci_dev *pdev, int bar, int size)
3080{
3081 int pos;
3082 u32 ctrl;
3083
3084 pos = pci_rebar_find_pos(pdev, bar);
3085 if (pos < 0)
3086 return pos;
3087
3088 pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
3089 ctrl &= ~PCI_REBAR_CTRL_BAR_SIZE;
3090 ctrl |= size << 8;
3091 pci_write_config_dword(pdev, pos + PCI_REBAR_CTRL, ctrl);
3092 return 0;
3093}
3094
3095/**
3096 * pci_enable_atomic_ops_to_root - enable AtomicOp requests to root port
3097 * @dev: the PCI device
3098 * @cap_mask: mask of desired AtomicOp sizes, including one or more of:
3099 * PCI_EXP_DEVCAP2_ATOMIC_COMP32
3100 * PCI_EXP_DEVCAP2_ATOMIC_COMP64
3101 * PCI_EXP_DEVCAP2_ATOMIC_COMP128
3102 *
3103 * Return 0 if all upstream bridges support AtomicOp routing, egress
3104 * blocking is disabled on all upstream ports, and the root port supports
3105 * the requested completion capabilities (32-bit, 64-bit and/or 128-bit
3106 * AtomicOp completion), or negative otherwise.
3107 */
3108int pci_enable_atomic_ops_to_root(struct pci_dev *dev, u32 cap_mask)
3109{
3110 struct pci_bus *bus = dev->bus;
3111 struct pci_dev *bridge;
3112 u32 cap, ctl2;
3113
3114 if (!pci_is_pcie(dev))
3115 return -EINVAL;
3116
3117 /*
3118 * Per PCIe r4.0, sec 6.15, endpoints and root ports may be
3119 * AtomicOp requesters. For now, we only support endpoints as
3120 * requesters and root ports as completers. No endpoints as
3121 * completers, and no peer-to-peer.
3122 */
3123
3124 switch (pci_pcie_type(dev)) {
3125 case PCI_EXP_TYPE_ENDPOINT:
3126 case PCI_EXP_TYPE_LEG_END:
3127 case PCI_EXP_TYPE_RC_END:
3128 break;
3129 default:
3130 return -EINVAL;
3131 }
3132
3133 while (bus->parent) {
3134 bridge = bus->self;
3135
3136 pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap);
3137
3138 switch (pci_pcie_type(bridge)) {
3139 /* Ensure switch ports support AtomicOp routing */
3140 case PCI_EXP_TYPE_UPSTREAM:
3141 case PCI_EXP_TYPE_DOWNSTREAM:
3142 if (!(cap & PCI_EXP_DEVCAP2_ATOMIC_ROUTE))
3143 return -EINVAL;
3144 break;
3145
3146 /* Ensure root port supports all the sizes we care about */
3147 case PCI_EXP_TYPE_ROOT_PORT:
3148 if ((cap & cap_mask) != cap_mask)
3149 return -EINVAL;
3150 break;
3151 }
3152
3153 /* Ensure upstream ports don't block AtomicOps on egress */
3154 if (!bridge->has_secondary_link) {
3155 pcie_capability_read_dword(bridge, PCI_EXP_DEVCTL2,
3156 &ctl2);
3157 if (ctl2 & PCI_EXP_DEVCTL2_ATOMIC_EGRESS_BLOCK)
3158 return -EINVAL;
3159 }
3160
3161 bus = bus->parent;
3162 }
3163
3164 pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
3165 PCI_EXP_DEVCTL2_ATOMIC_REQ);
3166 return 0;
3167}
3168EXPORT_SYMBOL(pci_enable_atomic_ops_to_root);
3169
3170/**
3171 * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
3172 * @dev: the PCI device
3173 * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTC, 4=INTD)
3174 *
3175 * Perform INTx swizzling for a device behind one level of bridge. This is
3176 * required by section 9.1 of the PCI-to-PCI bridge specification for devices
3177 * behind bridges on add-in cards. For devices with ARI enabled, the slot
3178 * number is always 0 (see the Implementation Note in section 2.2.8.1 of
3179 * the PCI Express Base Specification, Revision 2.1)
3180 */
3181u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin)
3182{
3183 int slot;
3184
3185 if (pci_ari_enabled(dev->bus))
3186 slot = 0;
3187 else
3188 slot = PCI_SLOT(dev->devfn);
3189
3190 return (((pin - 1) + slot) % 4) + 1;
3191}
3192
3193int pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
3194{
3195 u8 pin;
3196
3197 pin = dev->pin;
3198 if (!pin)
3199 return -1;
3200
3201 while (!pci_is_root_bus(dev->bus)) {
3202 pin = pci_swizzle_interrupt_pin(dev, pin);
3203 dev = dev->bus->self;
3204 }
3205 *bridge = dev;
3206 return pin;
3207}
3208
3209/**
3210 * pci_common_swizzle - swizzle INTx all the way to root bridge
3211 * @dev: the PCI device
3212 * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
3213 *
3214 * Perform INTx swizzling for a device. This traverses through all PCI-to-PCI
3215 * bridges all the way up to a PCI root bus.
3216 */
3217u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
3218{
3219 u8 pin = *pinp;
3220
3221 while (!pci_is_root_bus(dev->bus)) {
3222 pin = pci_swizzle_interrupt_pin(dev, pin);
3223 dev = dev->bus->self;
3224 }
3225 *pinp = pin;
3226 return PCI_SLOT(dev->devfn);
3227}
3228EXPORT_SYMBOL_GPL(pci_common_swizzle);
3229
3230/**
3231 * pci_release_region - Release a PCI bar
3232 * @pdev: PCI device whose resources were previously reserved by pci_request_region
3233 * @bar: BAR to release
3234 *
3235 * Releases the PCI I/O and memory resources previously reserved by a
3236 * successful call to pci_request_region. Call this function only
3237 * after all use of the PCI regions has ceased.
3238 */
3239void pci_release_region(struct pci_dev *pdev, int bar)
3240{
3241 struct pci_devres *dr;
3242
3243 if (pci_resource_len(pdev, bar) == 0)
3244 return;
3245 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
3246 release_region(pci_resource_start(pdev, bar),
3247 pci_resource_len(pdev, bar));
3248 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
3249 release_mem_region(pci_resource_start(pdev, bar),
3250 pci_resource_len(pdev, bar));
3251
3252 dr = find_pci_dr(pdev);
3253 if (dr)
3254 dr->region_mask &= ~(1 << bar);
3255}
3256EXPORT_SYMBOL(pci_release_region);
3257
3258/**
3259 * __pci_request_region - Reserved PCI I/O and memory resource
3260 * @pdev: PCI device whose resources are to be reserved
3261 * @bar: BAR to be reserved
3262 * @res_name: Name to be associated with resource.
3263 * @exclusive: whether the region access is exclusive or not
3264 *
3265 * Mark the PCI region associated with PCI device @pdev BR @bar as
3266 * being reserved by owner @res_name. Do not access any
3267 * address inside the PCI regions unless this call returns
3268 * successfully.
3269 *
3270 * If @exclusive is set, then the region is marked so that userspace
3271 * is explicitly not allowed to map the resource via /dev/mem or
3272 * sysfs MMIO access.
3273 *
3274 * Returns 0 on success, or %EBUSY on error. A warning
3275 * message is also printed on failure.
3276 */
3277static int __pci_request_region(struct pci_dev *pdev, int bar,
3278 const char *res_name, int exclusive)
3279{
3280 struct pci_devres *dr;
3281
3282 if (pci_resource_len(pdev, bar) == 0)
3283 return 0;
3284
3285 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
3286 if (!request_region(pci_resource_start(pdev, bar),
3287 pci_resource_len(pdev, bar), res_name))
3288 goto err_out;
3289 } else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
3290 if (!__request_mem_region(pci_resource_start(pdev, bar),
3291 pci_resource_len(pdev, bar), res_name,
3292 exclusive))
3293 goto err_out;
3294 }
3295
3296 dr = find_pci_dr(pdev);
3297 if (dr)
3298 dr->region_mask |= 1 << bar;
3299
3300 return 0;
3301
3302err_out:
3303 pci_warn(pdev, "BAR %d: can't reserve %pR\n", bar,
3304 &pdev->resource[bar]);
3305 return -EBUSY;
3306}
3307
3308/**
3309 * pci_request_region - Reserve PCI I/O and memory resource
3310 * @pdev: PCI device whose resources are to be reserved
3311 * @bar: BAR to be reserved
3312 * @res_name: Name to be associated with resource
3313 *
3314 * Mark the PCI region associated with PCI device @pdev BAR @bar as
3315 * being reserved by owner @res_name. Do not access any
3316 * address inside the PCI regions unless this call returns
3317 * successfully.
3318 *
3319 * Returns 0 on success, or %EBUSY on error. A warning
3320 * message is also printed on failure.
3321 */
3322int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
3323{
3324 return __pci_request_region(pdev, bar, res_name, 0);
3325}
3326EXPORT_SYMBOL(pci_request_region);
3327
3328/**
3329 * pci_request_region_exclusive - Reserved PCI I/O and memory resource
3330 * @pdev: PCI device whose resources are to be reserved
3331 * @bar: BAR to be reserved
3332 * @res_name: Name to be associated with resource.
3333 *
3334 * Mark the PCI region associated with PCI device @pdev BR @bar as
3335 * being reserved by owner @res_name. Do not access any
3336 * address inside the PCI regions unless this call returns
3337 * successfully.
3338 *
3339 * Returns 0 on success, or %EBUSY on error. A warning
3340 * message is also printed on failure.
3341 *
3342 * The key difference that _exclusive makes it that userspace is
3343 * explicitly not allowed to map the resource via /dev/mem or
3344 * sysfs.
3345 */
3346int pci_request_region_exclusive(struct pci_dev *pdev, int bar,
3347 const char *res_name)
3348{
3349 return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
3350}
3351EXPORT_SYMBOL(pci_request_region_exclusive);
3352
3353/**
3354 * pci_release_selected_regions - Release selected PCI I/O and memory resources
3355 * @pdev: PCI device whose resources were previously reserved
3356 * @bars: Bitmask of BARs to be released
3357 *
3358 * Release selected PCI I/O and memory resources previously reserved.
3359 * Call this function only after all use of the PCI regions has ceased.
3360 */
3361void pci_release_selected_regions(struct pci_dev *pdev, int bars)
3362{
3363 int i;
3364
3365 for (i = 0; i < 6; i++)
3366 if (bars & (1 << i))
3367 pci_release_region(pdev, i);
3368}
3369EXPORT_SYMBOL(pci_release_selected_regions);
3370
3371static int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
3372 const char *res_name, int excl)
3373{
3374 int i;
3375
3376 for (i = 0; i < 6; i++)
3377 if (bars & (1 << i))
3378 if (__pci_request_region(pdev, i, res_name, excl))
3379 goto err_out;
3380 return 0;
3381
3382err_out:
3383 while (--i >= 0)
3384 if (bars & (1 << i))
3385 pci_release_region(pdev, i);
3386
3387 return -EBUSY;
3388}
3389
3390
3391/**
3392 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
3393 * @pdev: PCI device whose resources are to be reserved
3394 * @bars: Bitmask of BARs to be requested
3395 * @res_name: Name to be associated with resource
3396 */
3397int pci_request_selected_regions(struct pci_dev *pdev, int bars,
3398 const char *res_name)
3399{
3400 return __pci_request_selected_regions(pdev, bars, res_name, 0);
3401}
3402EXPORT_SYMBOL(pci_request_selected_regions);
3403
3404int pci_request_selected_regions_exclusive(struct pci_dev *pdev, int bars,
3405 const char *res_name)
3406{
3407 return __pci_request_selected_regions(pdev, bars, res_name,
3408 IORESOURCE_EXCLUSIVE);
3409}
3410EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
3411
3412/**
3413 * pci_release_regions - Release reserved PCI I/O and memory resources
3414 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
3415 *
3416 * Releases all PCI I/O and memory resources previously reserved by a
3417 * successful call to pci_request_regions. Call this function only
3418 * after all use of the PCI regions has ceased.
3419 */
3420
3421void pci_release_regions(struct pci_dev *pdev)
3422{
3423 pci_release_selected_regions(pdev, (1 << 6) - 1);
3424}
3425EXPORT_SYMBOL(pci_release_regions);
3426
3427/**
3428 * pci_request_regions - Reserved PCI I/O and memory resources
3429 * @pdev: PCI device whose resources are to be reserved
3430 * @res_name: Name to be associated with resource.
3431 *
3432 * Mark all PCI regions associated with PCI device @pdev as
3433 * being reserved by owner @res_name. Do not access any
3434 * address inside the PCI regions unless this call returns
3435 * successfully.
3436 *
3437 * Returns 0 on success, or %EBUSY on error. A warning
3438 * message is also printed on failure.
3439 */
3440int pci_request_regions(struct pci_dev *pdev, const char *res_name)
3441{
3442 return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
3443}
3444EXPORT_SYMBOL(pci_request_regions);
3445
3446/**
3447 * pci_request_regions_exclusive - Reserved PCI I/O and memory resources
3448 * @pdev: PCI device whose resources are to be reserved
3449 * @res_name: Name to be associated with resource.
3450 *
3451 * Mark all PCI regions associated with PCI device @pdev as
3452 * being reserved by owner @res_name. Do not access any
3453 * address inside the PCI regions unless this call returns
3454 * successfully.
3455 *
3456 * pci_request_regions_exclusive() will mark the region so that
3457 * /dev/mem and the sysfs MMIO access will not be allowed.
3458 *
3459 * Returns 0 on success, or %EBUSY on error. A warning
3460 * message is also printed on failure.
3461 */
3462int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
3463{
3464 return pci_request_selected_regions_exclusive(pdev,
3465 ((1 << 6) - 1), res_name);
3466}
3467EXPORT_SYMBOL(pci_request_regions_exclusive);
3468
3469/*
3470 * Record the PCI IO range (expressed as CPU physical address + size).
3471 * Return a negative value if an error has occured, zero otherwise
3472 */
3473int pci_register_io_range(struct fwnode_handle *fwnode, phys_addr_t addr,
3474 resource_size_t size)
3475{
3476 int ret = 0;
3477#ifdef PCI_IOBASE
3478 struct logic_pio_hwaddr *range;
3479
3480 if (!size || addr + size < addr)
3481 return -EINVAL;
3482
3483 range = kzalloc(sizeof(*range), GFP_ATOMIC);
3484 if (!range)
3485 return -ENOMEM;
3486
3487 range->fwnode = fwnode;
3488 range->size = size;
3489 range->hw_start = addr;
3490 range->flags = LOGIC_PIO_CPU_MMIO;
3491
3492 ret = logic_pio_register_range(range);
3493 if (ret)
3494 kfree(range);
3495#endif
3496
3497 return ret;
3498}
3499
3500phys_addr_t pci_pio_to_address(unsigned long pio)
3501{
3502 phys_addr_t address = (phys_addr_t)OF_BAD_ADDR;
3503
3504#ifdef PCI_IOBASE
3505 if (pio >= MMIO_UPPER_LIMIT)
3506 return address;
3507
3508 address = logic_pio_to_hwaddr(pio);
3509#endif
3510
3511 return address;
3512}
3513
3514unsigned long __weak pci_address_to_pio(phys_addr_t address)
3515{
3516#ifdef PCI_IOBASE
3517 return logic_pio_trans_cpuaddr(address);
3518#else
3519 if (address > IO_SPACE_LIMIT)
3520 return (unsigned long)-1;
3521
3522 return (unsigned long) address;
3523#endif
3524}
3525
3526/**
3527 * pci_remap_iospace - Remap the memory mapped I/O space
3528 * @res: Resource describing the I/O space
3529 * @phys_addr: physical address of range to be mapped
3530 *
3531 * Remap the memory mapped I/O space described by the @res
3532 * and the CPU physical address @phys_addr into virtual address space.
3533 * Only architectures that have memory mapped IO functions defined
3534 * (and the PCI_IOBASE value defined) should call this function.
3535 */
3536int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
3537{
3538#if defined(PCI_IOBASE) && defined(CONFIG_MMU)
3539 unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start;
3540
3541 if (!(res->flags & IORESOURCE_IO))
3542 return -EINVAL;
3543
3544 if (res->end > IO_SPACE_LIMIT)
3545 return -EINVAL;
3546
3547 return ioremap_page_range(vaddr, vaddr + resource_size(res), phys_addr,
3548 pgprot_device(PAGE_KERNEL));
3549#else
3550 /* this architecture does not have memory mapped I/O space,
3551 so this function should never be called */
3552 WARN_ONCE(1, "This architecture does not support memory mapped I/O\n");
3553 return -ENODEV;
3554#endif
3555}
3556EXPORT_SYMBOL(pci_remap_iospace);
3557
3558/**
3559 * pci_unmap_iospace - Unmap the memory mapped I/O space
3560 * @res: resource to be unmapped
3561 *
3562 * Unmap the CPU virtual address @res from virtual address space.
3563 * Only architectures that have memory mapped IO functions defined
3564 * (and the PCI_IOBASE value defined) should call this function.
3565 */
3566void pci_unmap_iospace(struct resource *res)
3567{
3568#if defined(PCI_IOBASE) && defined(CONFIG_MMU)
3569 unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start;
3570
3571 unmap_kernel_range(vaddr, resource_size(res));
3572#endif
3573}
3574EXPORT_SYMBOL(pci_unmap_iospace);
3575
3576/**
3577 * devm_pci_remap_cfgspace - Managed pci_remap_cfgspace()
3578 * @dev: Generic device to remap IO address for
3579 * @offset: Resource address to map
3580 * @size: Size of map
3581 *
3582 * Managed pci_remap_cfgspace(). Map is automatically unmapped on driver
3583 * detach.
3584 */
3585void __iomem *devm_pci_remap_cfgspace(struct device *dev,
3586 resource_size_t offset,
3587 resource_size_t size)
3588{
3589 void __iomem **ptr, *addr;
3590
3591 ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
3592 if (!ptr)
3593 return NULL;
3594
3595 addr = pci_remap_cfgspace(offset, size);
3596 if (addr) {
3597 *ptr = addr;
3598 devres_add(dev, ptr);
3599 } else
3600 devres_free(ptr);
3601
3602 return addr;
3603}
3604EXPORT_SYMBOL(devm_pci_remap_cfgspace);
3605
3606/**
3607 * devm_pci_remap_cfg_resource - check, request region and ioremap cfg resource
3608 * @dev: generic device to handle the resource for
3609 * @res: configuration space resource to be handled
3610 *
3611 * Checks that a resource is a valid memory region, requests the memory
3612 * region and ioremaps with pci_remap_cfgspace() API that ensures the
3613 * proper PCI configuration space memory attributes are guaranteed.
3614 *
3615 * All operations are managed and will be undone on driver detach.
3616 *
3617 * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
3618 * on failure. Usage example::
3619 *
3620 * res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
3621 * base = devm_pci_remap_cfg_resource(&pdev->dev, res);
3622 * if (IS_ERR(base))
3623 * return PTR_ERR(base);
3624 */
3625void __iomem *devm_pci_remap_cfg_resource(struct device *dev,
3626 struct resource *res)
3627{
3628 resource_size_t size;
3629 const char *name;
3630 void __iomem *dest_ptr;
3631
3632 BUG_ON(!dev);
3633
3634 if (!res || resource_type(res) != IORESOURCE_MEM) {
3635 dev_err(dev, "invalid resource\n");
3636 return IOMEM_ERR_PTR(-EINVAL);
3637 }
3638
3639 size = resource_size(res);
3640 name = res->name ?: dev_name(dev);
3641
3642 if (!devm_request_mem_region(dev, res->start, size, name)) {
3643 dev_err(dev, "can't request region for resource %pR\n", res);
3644 return IOMEM_ERR_PTR(-EBUSY);
3645 }
3646
3647 dest_ptr = devm_pci_remap_cfgspace(dev, res->start, size);
3648 if (!dest_ptr) {
3649 dev_err(dev, "ioremap failed for resource %pR\n", res);
3650 devm_release_mem_region(dev, res->start, size);
3651 dest_ptr = IOMEM_ERR_PTR(-ENOMEM);
3652 }
3653
3654 return dest_ptr;
3655}
3656EXPORT_SYMBOL(devm_pci_remap_cfg_resource);
3657
3658static void __pci_set_master(struct pci_dev *dev, bool enable)
3659{
3660 u16 old_cmd, cmd;
3661
3662 pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
3663 if (enable)
3664 cmd = old_cmd | PCI_COMMAND_MASTER;
3665 else
3666 cmd = old_cmd & ~PCI_COMMAND_MASTER;
3667 if (cmd != old_cmd) {
3668 pci_dbg(dev, "%s bus mastering\n",
3669 enable ? "enabling" : "disabling");
3670 pci_write_config_word(dev, PCI_COMMAND, cmd);
3671 }
3672 dev->is_busmaster = enable;
3673}
3674
3675/**
3676 * pcibios_setup - process "pci=" kernel boot arguments
3677 * @str: string used to pass in "pci=" kernel boot arguments
3678 *
3679 * Process kernel boot arguments. This is the default implementation.
3680 * Architecture specific implementations can override this as necessary.
3681 */
3682char * __weak __init pcibios_setup(char *str)
3683{
3684 return str;
3685}
3686
3687/**
3688 * pcibios_set_master - enable PCI bus-mastering for device dev
3689 * @dev: the PCI device to enable
3690 *
3691 * Enables PCI bus-mastering for the device. This is the default
3692 * implementation. Architecture specific implementations can override
3693 * this if necessary.
3694 */
3695void __weak pcibios_set_master(struct pci_dev *dev)
3696{
3697 u8 lat;
3698
3699 /* The latency timer doesn't apply to PCIe (either Type 0 or Type 1) */
3700 if (pci_is_pcie(dev))
3701 return;
3702
3703 pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
3704 if (lat < 16)
3705 lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
3706 else if (lat > pcibios_max_latency)
3707 lat = pcibios_max_latency;
3708 else
3709 return;
3710
3711 pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
3712}
3713
3714/**
3715 * pci_set_master - enables bus-mastering for device dev
3716 * @dev: the PCI device to enable
3717 *
3718 * Enables bus-mastering on the device and calls pcibios_set_master()
3719 * to do the needed arch specific settings.
3720 */
3721void pci_set_master(struct pci_dev *dev)
3722{
3723 __pci_set_master(dev, true);
3724 pcibios_set_master(dev);
3725}
3726EXPORT_SYMBOL(pci_set_master);
3727
3728/**
3729 * pci_clear_master - disables bus-mastering for device dev
3730 * @dev: the PCI device to disable
3731 */
3732void pci_clear_master(struct pci_dev *dev)
3733{
3734 __pci_set_master(dev, false);
3735}
3736EXPORT_SYMBOL(pci_clear_master);
3737
3738/**
3739 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
3740 * @dev: the PCI device for which MWI is to be enabled
3741 *
3742 * Helper function for pci_set_mwi.
3743 * Originally copied from drivers/net/acenic.c.
3744 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
3745 *
3746 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
3747 */
3748int pci_set_cacheline_size(struct pci_dev *dev)
3749{
3750 u8 cacheline_size;
3751
3752 if (!pci_cache_line_size)
3753 return -EINVAL;
3754
3755 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
3756 equal to or multiple of the right value. */
3757 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
3758 if (cacheline_size >= pci_cache_line_size &&
3759 (cacheline_size % pci_cache_line_size) == 0)
3760 return 0;
3761
3762 /* Write the correct value. */
3763 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
3764 /* Read it back. */
3765 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
3766 if (cacheline_size == pci_cache_line_size)
3767 return 0;
3768
3769 pci_printk(KERN_DEBUG, dev, "cache line size of %d is not supported\n",
3770 pci_cache_line_size << 2);
3771
3772 return -EINVAL;
3773}
3774EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
3775
3776/**
3777 * pci_set_mwi - enables memory-write-invalidate PCI transaction
3778 * @dev: the PCI device for which MWI is enabled
3779 *
3780 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
3781 *
3782 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
3783 */
3784int pci_set_mwi(struct pci_dev *dev)
3785{
3786#ifdef PCI_DISABLE_MWI
3787 return 0;
3788#else
3789 int rc;
3790 u16 cmd;
3791
3792 rc = pci_set_cacheline_size(dev);
3793 if (rc)
3794 return rc;
3795
3796 pci_read_config_word(dev, PCI_COMMAND, &cmd);
3797 if (!(cmd & PCI_COMMAND_INVALIDATE)) {
3798 pci_dbg(dev, "enabling Mem-Wr-Inval\n");
3799 cmd |= PCI_COMMAND_INVALIDATE;
3800 pci_write_config_word(dev, PCI_COMMAND, cmd);
3801 }
3802 return 0;
3803#endif
3804}
3805EXPORT_SYMBOL(pci_set_mwi);
3806
3807/**
3808 * pcim_set_mwi - a device-managed pci_set_mwi()
3809 * @dev: the PCI device for which MWI is enabled
3810 *
3811 * Managed pci_set_mwi().
3812 *
3813 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
3814 */
3815int pcim_set_mwi(struct pci_dev *dev)
3816{
3817 struct pci_devres *dr;
3818
3819 dr = find_pci_dr(dev);
3820 if (!dr)
3821 return -ENOMEM;
3822
3823 dr->mwi = 1;
3824 return pci_set_mwi(dev);
3825}
3826EXPORT_SYMBOL(pcim_set_mwi);
3827
3828/**
3829 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
3830 * @dev: the PCI device for which MWI is enabled
3831 *
3832 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
3833 * Callers are not required to check the return value.
3834 *
3835 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
3836 */
3837int pci_try_set_mwi(struct pci_dev *dev)
3838{
3839#ifdef PCI_DISABLE_MWI
3840 return 0;
3841#else
3842 return pci_set_mwi(dev);
3843#endif
3844}
3845EXPORT_SYMBOL(pci_try_set_mwi);
3846
3847/**
3848 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
3849 * @dev: the PCI device to disable
3850 *
3851 * Disables PCI Memory-Write-Invalidate transaction on the device
3852 */
3853void pci_clear_mwi(struct pci_dev *dev)
3854{
3855#ifndef PCI_DISABLE_MWI
3856 u16 cmd;
3857
3858 pci_read_config_word(dev, PCI_COMMAND, &cmd);
3859 if (cmd & PCI_COMMAND_INVALIDATE) {
3860 cmd &= ~PCI_COMMAND_INVALIDATE;
3861 pci_write_config_word(dev, PCI_COMMAND, cmd);
3862 }
3863#endif
3864}
3865EXPORT_SYMBOL(pci_clear_mwi);
3866
3867/**
3868 * pci_intx - enables/disables PCI INTx for device dev
3869 * @pdev: the PCI device to operate on
3870 * @enable: boolean: whether to enable or disable PCI INTx
3871 *
3872 * Enables/disables PCI INTx for device dev
3873 */
3874void pci_intx(struct pci_dev *pdev, int enable)
3875{
3876 u16 pci_command, new;
3877
3878 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
3879
3880 if (enable)
3881 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
3882 else
3883 new = pci_command | PCI_COMMAND_INTX_DISABLE;
3884
3885 if (new != pci_command) {
3886 struct pci_devres *dr;
3887
3888 pci_write_config_word(pdev, PCI_COMMAND, new);
3889
3890 dr = find_pci_dr(pdev);
3891 if (dr && !dr->restore_intx) {
3892 dr->restore_intx = 1;
3893 dr->orig_intx = !enable;
3894 }
3895 }
3896}
3897EXPORT_SYMBOL_GPL(pci_intx);
3898
3899static bool pci_check_and_set_intx_mask(struct pci_dev *dev, bool mask)
3900{
3901 struct pci_bus *bus = dev->bus;
3902 bool mask_updated = true;
3903 u32 cmd_status_dword;
3904 u16 origcmd, newcmd;
3905 unsigned long flags;
3906 bool irq_pending;
3907
3908 /*
3909 * We do a single dword read to retrieve both command and status.
3910 * Document assumptions that make this possible.
3911 */
3912 BUILD_BUG_ON(PCI_COMMAND % 4);
3913 BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
3914
3915 raw_spin_lock_irqsave(&pci_lock, flags);
3916
3917 bus->ops->read(bus, dev->devfn, PCI_COMMAND, 4, &cmd_status_dword);
3918
3919 irq_pending = (cmd_status_dword >> 16) & PCI_STATUS_INTERRUPT;
3920
3921 /*
3922 * Check interrupt status register to see whether our device
3923 * triggered the interrupt (when masking) or the next IRQ is
3924 * already pending (when unmasking).
3925 */
3926 if (mask != irq_pending) {
3927 mask_updated = false;
3928 goto done;
3929 }
3930
3931 origcmd = cmd_status_dword;
3932 newcmd = origcmd & ~PCI_COMMAND_INTX_DISABLE;
3933 if (mask)
3934 newcmd |= PCI_COMMAND_INTX_DISABLE;
3935 if (newcmd != origcmd)
3936 bus->ops->write(bus, dev->devfn, PCI_COMMAND, 2, newcmd);
3937
3938done:
3939 raw_spin_unlock_irqrestore(&pci_lock, flags);
3940
3941 return mask_updated;
3942}
3943
3944/**
3945 * pci_check_and_mask_intx - mask INTx on pending interrupt
3946 * @dev: the PCI device to operate on
3947 *
3948 * Check if the device dev has its INTx line asserted, mask it and
3949 * return true in that case. False is returned if no interrupt was
3950 * pending.
3951 */
3952bool pci_check_and_mask_intx(struct pci_dev *dev)
3953{
3954 return pci_check_and_set_intx_mask(dev, true);
3955}
3956EXPORT_SYMBOL_GPL(pci_check_and_mask_intx);
3957
3958/**
3959 * pci_check_and_unmask_intx - unmask INTx if no interrupt is pending
3960 * @dev: the PCI device to operate on
3961 *
3962 * Check if the device dev has its INTx line asserted, unmask it if not
3963 * and return true. False is returned and the mask remains active if
3964 * there was still an interrupt pending.
3965 */
3966bool pci_check_and_unmask_intx(struct pci_dev *dev)
3967{
3968 return pci_check_and_set_intx_mask(dev, false);
3969}
3970EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx);
3971
3972/**
3973 * pci_wait_for_pending_transaction - waits for pending transaction
3974 * @dev: the PCI device to operate on
3975 *
3976 * Return 0 if transaction is pending 1 otherwise.
3977 */
3978int pci_wait_for_pending_transaction(struct pci_dev *dev)
3979{
3980 if (!pci_is_pcie(dev))
3981 return 1;
3982
3983 return pci_wait_for_pending(dev, pci_pcie_cap(dev) + PCI_EXP_DEVSTA,
3984 PCI_EXP_DEVSTA_TRPND);
3985}
3986EXPORT_SYMBOL(pci_wait_for_pending_transaction);
3987
3988static int pci_dev_wait(struct pci_dev *dev, char *reset_type, int timeout)
3989{
3990 int delay = 1;
3991 u32 id;
3992
3993 /*
3994 * After reset, the device should not silently discard config
3995 * requests, but it may still indicate that it needs more time by
3996 * responding to them with CRS completions. The Root Port will
3997 * generally synthesize ~0 data to complete the read (except when
3998 * CRS SV is enabled and the read was for the Vendor ID; in that
3999 * case it synthesizes 0x0001 data).
4000 *
4001 * Wait for the device to return a non-CRS completion. Read the
4002 * Command register instead of Vendor ID so we don't have to
4003 * contend with the CRS SV value.
4004 */
4005 pci_read_config_dword(dev, PCI_COMMAND, &id);
4006 while (id == ~0) {
4007 if (delay > timeout) {
4008 pci_warn(dev, "not ready %dms after %s; giving up\n",
4009 delay - 1, reset_type);
4010 return -ENOTTY;
4011 }
4012
4013 if (delay > 1000)
4014 pci_info(dev, "not ready %dms after %s; waiting\n",
4015 delay - 1, reset_type);
4016
4017 msleep(delay);
4018 delay *= 2;
4019 pci_read_config_dword(dev, PCI_COMMAND, &id);
4020 }
4021
4022 if (delay > 1000)
4023 pci_info(dev, "ready %dms after %s\n", delay - 1,
4024 reset_type);
4025
4026 return 0;
4027}
4028
4029/**
4030 * pcie_has_flr - check if a device supports function level resets
4031 * @dev: device to check
4032 *
4033 * Returns true if the device advertises support for PCIe function level
4034 * resets.
4035 */
4036static bool pcie_has_flr(struct pci_dev *dev)
4037{
4038 u32 cap;
4039
4040 if (dev->dev_flags & PCI_DEV_FLAGS_NO_FLR_RESET)
4041 return false;
4042
4043 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
4044 return cap & PCI_EXP_DEVCAP_FLR;
4045}
4046
4047/**
4048 * pcie_flr - initiate a PCIe function level reset
4049 * @dev: device to reset
4050 *
4051 * Initiate a function level reset on @dev. The caller should ensure the
4052 * device supports FLR before calling this function, e.g. by using the
4053 * pcie_has_flr() helper.
4054 */
4055int pcie_flr(struct pci_dev *dev)
4056{
4057 if (!pci_wait_for_pending_transaction(dev))
4058 pci_err(dev, "timed out waiting for pending transaction; performing function level reset anyway\n");
4059
4060 pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR);
4061
4062 /*
4063 * Per PCIe r4.0, sec 6.6.2, a device must complete an FLR within
4064 * 100ms, but may silently discard requests while the FLR is in
4065 * progress. Wait 100ms before trying to access the device.
4066 */
4067 msleep(100);
4068
4069 return pci_dev_wait(dev, "FLR", PCIE_RESET_READY_POLL_MS);
4070}
4071EXPORT_SYMBOL_GPL(pcie_flr);
4072
4073static int pci_af_flr(struct pci_dev *dev, int probe)
4074{
4075 int pos;
4076 u8 cap;
4077
4078 pos = pci_find_capability(dev, PCI_CAP_ID_AF);
4079 if (!pos)
4080 return -ENOTTY;
4081
4082 if (dev->dev_flags & PCI_DEV_FLAGS_NO_FLR_RESET)
4083 return -ENOTTY;
4084
4085 pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
4086 if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
4087 return -ENOTTY;
4088
4089 if (probe)
4090 return 0;
4091
4092 /*
4093 * Wait for Transaction Pending bit to clear. A word-aligned test
4094 * is used, so we use the conrol offset rather than status and shift
4095 * the test bit to match.
4096 */
4097 if (!pci_wait_for_pending(dev, pos + PCI_AF_CTRL,
4098 PCI_AF_STATUS_TP << 8))
4099 pci_err(dev, "timed out waiting for pending transaction; performing AF function level reset anyway\n");
4100
4101 pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
4102
4103 /*
4104 * Per Advanced Capabilities for Conventional PCI ECN, 13 April 2006,
4105 * updated 27 July 2006; a device must complete an FLR within
4106 * 100ms, but may silently discard requests while the FLR is in
4107 * progress. Wait 100ms before trying to access the device.
4108 */
4109 msleep(100);
4110
4111 return pci_dev_wait(dev, "AF_FLR", PCIE_RESET_READY_POLL_MS);
4112}
4113
4114/**
4115 * pci_pm_reset - Put device into PCI_D3 and back into PCI_D0.
4116 * @dev: Device to reset.
4117 * @probe: If set, only check if the device can be reset this way.
4118 *
4119 * If @dev supports native PCI PM and its PCI_PM_CTRL_NO_SOFT_RESET flag is
4120 * unset, it will be reinitialized internally when going from PCI_D3hot to
4121 * PCI_D0. If that's the case and the device is not in a low-power state
4122 * already, force it into PCI_D3hot and back to PCI_D0, causing it to be reset.
4123 *
4124 * NOTE: This causes the caller to sleep for twice the device power transition
4125 * cooldown period, which for the D0->D3hot and D3hot->D0 transitions is 10 ms
4126 * by default (i.e. unless the @dev's d3_delay field has a different value).
4127 * Moreover, only devices in D0 can be reset by this function.
4128 */
4129static int pci_pm_reset(struct pci_dev *dev, int probe)
4130{
4131 u16 csr;
4132
4133 if (!dev->pm_cap || dev->dev_flags & PCI_DEV_FLAGS_NO_PM_RESET)
4134 return -ENOTTY;
4135
4136 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
4137 if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
4138 return -ENOTTY;
4139
4140 if (probe)
4141 return 0;
4142
4143 if (dev->current_state != PCI_D0)
4144 return -EINVAL;
4145
4146 csr &= ~PCI_PM_CTRL_STATE_MASK;
4147 csr |= PCI_D3hot;
4148 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
4149 pci_dev_d3_sleep(dev);
4150
4151 csr &= ~PCI_PM_CTRL_STATE_MASK;
4152 csr |= PCI_D0;
4153 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
4154 pci_dev_d3_sleep(dev);
4155
4156 return pci_dev_wait(dev, "PM D3->D0", PCIE_RESET_READY_POLL_MS);
4157}
4158
4159void pci_reset_secondary_bus(struct pci_dev *dev)
4160{
4161 u16 ctrl;
4162
4163 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &ctrl);
4164 ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
4165 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
4166
4167 /*
4168 * PCI spec v3.0 7.6.4.2 requires minimum Trst of 1ms. Double
4169 * this to 2ms to ensure that we meet the minimum requirement.
4170 */
4171 msleep(2);
4172
4173 ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
4174 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
4175
4176 /*
4177 * Trhfa for conventional PCI is 2^25 clock cycles.
4178 * Assuming a minimum 33MHz clock this results in a 1s
4179 * delay before we can consider subordinate devices to
4180 * be re-initialized. PCIe has some ways to shorten this,
4181 * but we don't make use of them yet.
4182 */
4183 ssleep(1);
4184}
4185
4186void __weak pcibios_reset_secondary_bus(struct pci_dev *dev)
4187{
4188 pci_reset_secondary_bus(dev);
4189}
4190
4191/**
4192 * pci_reset_bridge_secondary_bus - Reset the secondary bus on a PCI bridge.
4193 * @dev: Bridge device
4194 *
4195 * Use the bridge control register to assert reset on the secondary bus.
4196 * Devices on the secondary bus are left in power-on state.
4197 */
4198int pci_reset_bridge_secondary_bus(struct pci_dev *dev)
4199{
4200 pcibios_reset_secondary_bus(dev);
4201
4202 return pci_dev_wait(dev, "bus reset", PCIE_RESET_READY_POLL_MS);
4203}
4204EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus);
4205
4206static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
4207{
4208 struct pci_dev *pdev;
4209
4210 if (pci_is_root_bus(dev->bus) || dev->subordinate ||
4211 !dev->bus->self || dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
4212 return -ENOTTY;
4213
4214 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
4215 if (pdev != dev)
4216 return -ENOTTY;
4217
4218 if (probe)
4219 return 0;
4220
4221 pci_reset_bridge_secondary_bus(dev->bus->self);
4222
4223 return 0;
4224}
4225
4226static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe)
4227{
4228 int rc = -ENOTTY;
4229
4230 if (!hotplug || !try_module_get(hotplug->ops->owner))
4231 return rc;
4232
4233 if (hotplug->ops->reset_slot)
4234 rc = hotplug->ops->reset_slot(hotplug, probe);
4235
4236 module_put(hotplug->ops->owner);
4237
4238 return rc;
4239}
4240
4241static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe)
4242{
4243 struct pci_dev *pdev;
4244
4245 if (dev->subordinate || !dev->slot ||
4246 dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
4247 return -ENOTTY;
4248
4249 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
4250 if (pdev != dev && pdev->slot == dev->slot)
4251 return -ENOTTY;
4252
4253 return pci_reset_hotplug_slot(dev->slot->hotplug, probe);
4254}
4255
4256static void pci_dev_lock(struct pci_dev *dev)
4257{
4258 pci_cfg_access_lock(dev);
4259 /* block PM suspend, driver probe, etc. */
4260 device_lock(&dev->dev);
4261}
4262
4263/* Return 1 on successful lock, 0 on contention */
4264static int pci_dev_trylock(struct pci_dev *dev)
4265{
4266 if (pci_cfg_access_trylock(dev)) {
4267 if (device_trylock(&dev->dev))
4268 return 1;
4269 pci_cfg_access_unlock(dev);
4270 }
4271
4272 return 0;
4273}
4274
4275static void pci_dev_unlock(struct pci_dev *dev)
4276{
4277 device_unlock(&dev->dev);
4278 pci_cfg_access_unlock(dev);
4279}
4280
4281static void pci_dev_save_and_disable(struct pci_dev *dev)
4282{
4283 const struct pci_error_handlers *err_handler =
4284 dev->driver ? dev->driver->err_handler : NULL;
4285
4286 /*
4287 * dev->driver->err_handler->reset_prepare() is protected against
4288 * races with ->remove() by the device lock, which must be held by
4289 * the caller.
4290 */
4291 if (err_handler && err_handler->reset_prepare)
4292 err_handler->reset_prepare(dev);
4293
4294 /*
4295 * Wake-up device prior to save. PM registers default to D0 after
4296 * reset and a simple register restore doesn't reliably return
4297 * to a non-D0 state anyway.
4298 */
4299 pci_set_power_state(dev, PCI_D0);
4300
4301 pci_save_state(dev);
4302 /*
4303 * Disable the device by clearing the Command register, except for
4304 * INTx-disable which is set. This not only disables MMIO and I/O port
4305 * BARs, but also prevents the device from being Bus Master, preventing
4306 * DMA from the device including MSI/MSI-X interrupts. For PCI 2.3
4307 * compliant devices, INTx-disable prevents legacy interrupts.
4308 */
4309 pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
4310}
4311
4312static void pci_dev_restore(struct pci_dev *dev)
4313{
4314 const struct pci_error_handlers *err_handler =
4315 dev->driver ? dev->driver->err_handler : NULL;
4316
4317 pci_restore_state(dev);
4318
4319 /*
4320 * dev->driver->err_handler->reset_done() is protected against
4321 * races with ->remove() by the device lock, which must be held by
4322 * the caller.
4323 */
4324 if (err_handler && err_handler->reset_done)
4325 err_handler->reset_done(dev);
4326}
4327
4328/**
4329 * __pci_reset_function_locked - reset a PCI device function while holding
4330 * the @dev mutex lock.
4331 * @dev: PCI device to reset
4332 *
4333 * Some devices allow an individual function to be reset without affecting
4334 * other functions in the same device. The PCI device must be responsive
4335 * to PCI config space in order to use this function.
4336 *
4337 * The device function is presumed to be unused and the caller is holding
4338 * the device mutex lock when this function is called.
4339 * Resetting the device will make the contents of PCI configuration space
4340 * random, so any caller of this must be prepared to reinitialise the
4341 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
4342 * etc.
4343 *
4344 * Returns 0 if the device function was successfully reset or negative if the
4345 * device doesn't support resetting a single function.
4346 */
4347int __pci_reset_function_locked(struct pci_dev *dev)
4348{
4349 int rc;
4350
4351 might_sleep();
4352
4353 /*
4354 * A reset method returns -ENOTTY if it doesn't support this device
4355 * and we should try the next method.
4356 *
4357 * If it returns 0 (success), we're finished. If it returns any
4358 * other error, we're also finished: this indicates that further
4359 * reset mechanisms might be broken on the device.
4360 */
4361 rc = pci_dev_specific_reset(dev, 0);
4362 if (rc != -ENOTTY)
4363 return rc;
4364 if (pcie_has_flr(dev)) {
4365 rc = pcie_flr(dev);
4366 if (rc != -ENOTTY)
4367 return rc;
4368 }
4369 rc = pci_af_flr(dev, 0);
4370 if (rc != -ENOTTY)
4371 return rc;
4372 rc = pci_pm_reset(dev, 0);
4373 if (rc != -ENOTTY)
4374 return rc;
4375 rc = pci_dev_reset_slot_function(dev, 0);
4376 if (rc != -ENOTTY)
4377 return rc;
4378 return pci_parent_bus_reset(dev, 0);
4379}
4380EXPORT_SYMBOL_GPL(__pci_reset_function_locked);
4381
4382/**
4383 * pci_probe_reset_function - check whether the device can be safely reset
4384 * @dev: PCI device to reset
4385 *
4386 * Some devices allow an individual function to be reset without affecting
4387 * other functions in the same device. The PCI device must be responsive
4388 * to PCI config space in order to use this function.
4389 *
4390 * Returns 0 if the device function can be reset or negative if the
4391 * device doesn't support resetting a single function.
4392 */
4393int pci_probe_reset_function(struct pci_dev *dev)
4394{
4395 int rc;
4396
4397 might_sleep();
4398
4399 rc = pci_dev_specific_reset(dev, 1);
4400 if (rc != -ENOTTY)
4401 return rc;
4402 if (pcie_has_flr(dev))
4403 return 0;
4404 rc = pci_af_flr(dev, 1);
4405 if (rc != -ENOTTY)
4406 return rc;
4407 rc = pci_pm_reset(dev, 1);
4408 if (rc != -ENOTTY)
4409 return rc;
4410 rc = pci_dev_reset_slot_function(dev, 1);
4411 if (rc != -ENOTTY)
4412 return rc;
4413
4414 return pci_parent_bus_reset(dev, 1);
4415}
4416
4417/**
4418 * pci_reset_function - quiesce and reset a PCI device function
4419 * @dev: PCI device to reset
4420 *
4421 * Some devices allow an individual function to be reset without affecting
4422 * other functions in the same device. The PCI device must be responsive
4423 * to PCI config space in order to use this function.
4424 *
4425 * This function does not just reset the PCI portion of a device, but
4426 * clears all the state associated with the device. This function differs
4427 * from __pci_reset_function_locked() in that it saves and restores device state
4428 * over the reset and takes the PCI device lock.
4429 *
4430 * Returns 0 if the device function was successfully reset or negative if the
4431 * device doesn't support resetting a single function.
4432 */
4433int pci_reset_function(struct pci_dev *dev)
4434{
4435 int rc;
4436
4437 if (!dev->reset_fn)
4438 return -ENOTTY;
4439
4440 pci_dev_lock(dev);
4441 pci_dev_save_and_disable(dev);
4442
4443 rc = __pci_reset_function_locked(dev);
4444
4445 pci_dev_restore(dev);
4446 pci_dev_unlock(dev);
4447
4448 return rc;
4449}
4450EXPORT_SYMBOL_GPL(pci_reset_function);
4451
4452/**
4453 * pci_reset_function_locked - quiesce and reset a PCI device function
4454 * @dev: PCI device to reset
4455 *
4456 * Some devices allow an individual function to be reset without affecting
4457 * other functions in the same device. The PCI device must be responsive
4458 * to PCI config space in order to use this function.
4459 *
4460 * This function does not just reset the PCI portion of a device, but
4461 * clears all the state associated with the device. This function differs
4462 * from __pci_reset_function_locked() in that it saves and restores device state
4463 * over the reset. It also differs from pci_reset_function() in that it
4464 * requires the PCI device lock to be held.
4465 *
4466 * Returns 0 if the device function was successfully reset or negative if the
4467 * device doesn't support resetting a single function.
4468 */
4469int pci_reset_function_locked(struct pci_dev *dev)
4470{
4471 int rc;
4472
4473 if (!dev->reset_fn)
4474 return -ENOTTY;
4475
4476 pci_dev_save_and_disable(dev);
4477
4478 rc = __pci_reset_function_locked(dev);
4479
4480 pci_dev_restore(dev);
4481
4482 return rc;
4483}
4484EXPORT_SYMBOL_GPL(pci_reset_function_locked);
4485
4486/**
4487 * pci_try_reset_function - quiesce and reset a PCI device function
4488 * @dev: PCI device to reset
4489 *
4490 * Same as above, except return -EAGAIN if unable to lock device.
4491 */
4492int pci_try_reset_function(struct pci_dev *dev)
4493{
4494 int rc;
4495
4496 if (!dev->reset_fn)
4497 return -ENOTTY;
4498
4499 if (!pci_dev_trylock(dev))
4500 return -EAGAIN;
4501
4502 pci_dev_save_and_disable(dev);
4503 rc = __pci_reset_function_locked(dev);
4504 pci_dev_restore(dev);
4505 pci_dev_unlock(dev);
4506
4507 return rc;
4508}
4509EXPORT_SYMBOL_GPL(pci_try_reset_function);
4510
4511/* Do any devices on or below this bus prevent a bus reset? */
4512static bool pci_bus_resetable(struct pci_bus *bus)
4513{
4514 struct pci_dev *dev;
4515
4516
4517 if (bus->self && (bus->self->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET))
4518 return false;
4519
4520 list_for_each_entry(dev, &bus->devices, bus_list) {
4521 if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
4522 (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
4523 return false;
4524 }
4525
4526 return true;
4527}
4528
4529/* Lock devices from the top of the tree down */
4530static void pci_bus_lock(struct pci_bus *bus)
4531{
4532 struct pci_dev *dev;
4533
4534 list_for_each_entry(dev, &bus->devices, bus_list) {
4535 pci_dev_lock(dev);
4536 if (dev->subordinate)
4537 pci_bus_lock(dev->subordinate);
4538 }
4539}
4540
4541/* Unlock devices from the bottom of the tree up */
4542static void pci_bus_unlock(struct pci_bus *bus)
4543{
4544 struct pci_dev *dev;
4545
4546 list_for_each_entry(dev, &bus->devices, bus_list) {
4547 if (dev->subordinate)
4548 pci_bus_unlock(dev->subordinate);
4549 pci_dev_unlock(dev);
4550 }
4551}
4552
4553/* Return 1 on successful lock, 0 on contention */
4554static int pci_bus_trylock(struct pci_bus *bus)
4555{
4556 struct pci_dev *dev;
4557
4558 list_for_each_entry(dev, &bus->devices, bus_list) {
4559 if (!pci_dev_trylock(dev))
4560 goto unlock;
4561 if (dev->subordinate) {
4562 if (!pci_bus_trylock(dev->subordinate)) {
4563 pci_dev_unlock(dev);
4564 goto unlock;
4565 }
4566 }
4567 }
4568 return 1;
4569
4570unlock:
4571 list_for_each_entry_continue_reverse(dev, &bus->devices, bus_list) {
4572 if (dev->subordinate)
4573 pci_bus_unlock(dev->subordinate);
4574 pci_dev_unlock(dev);
4575 }
4576 return 0;
4577}
4578
4579/* Do any devices on or below this slot prevent a bus reset? */
4580static bool pci_slot_resetable(struct pci_slot *slot)
4581{
4582 struct pci_dev *dev;
4583
4584 if (slot->bus->self &&
4585 (slot->bus->self->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET))
4586 return false;
4587
4588 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
4589 if (!dev->slot || dev->slot != slot)
4590 continue;
4591 if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
4592 (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
4593 return false;
4594 }
4595
4596 return true;
4597}
4598
4599/* Lock devices from the top of the tree down */
4600static void pci_slot_lock(struct pci_slot *slot)
4601{
4602 struct pci_dev *dev;
4603
4604 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
4605 if (!dev->slot || dev->slot != slot)
4606 continue;
4607 pci_dev_lock(dev);
4608 if (dev->subordinate)
4609 pci_bus_lock(dev->subordinate);
4610 }
4611}
4612
4613/* Unlock devices from the bottom of the tree up */
4614static void pci_slot_unlock(struct pci_slot *slot)
4615{
4616 struct pci_dev *dev;
4617
4618 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
4619 if (!dev->slot || dev->slot != slot)
4620 continue;
4621 if (dev->subordinate)
4622 pci_bus_unlock(dev->subordinate);
4623 pci_dev_unlock(dev);
4624 }
4625}
4626
4627/* Return 1 on successful lock, 0 on contention */
4628static int pci_slot_trylock(struct pci_slot *slot)
4629{
4630 struct pci_dev *dev;
4631
4632 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
4633 if (!dev->slot || dev->slot != slot)
4634 continue;
4635 if (!pci_dev_trylock(dev))
4636 goto unlock;
4637 if (dev->subordinate) {
4638 if (!pci_bus_trylock(dev->subordinate)) {
4639 pci_dev_unlock(dev);
4640 goto unlock;
4641 }
4642 }
4643 }
4644 return 1;
4645
4646unlock:
4647 list_for_each_entry_continue_reverse(dev,
4648 &slot->bus->devices, bus_list) {
4649 if (!dev->slot || dev->slot != slot)
4650 continue;
4651 if (dev->subordinate)
4652 pci_bus_unlock(dev->subordinate);
4653 pci_dev_unlock(dev);
4654 }
4655 return 0;
4656}
4657
4658/* Save and disable devices from the top of the tree down */
4659static void pci_bus_save_and_disable(struct pci_bus *bus)
4660{
4661 struct pci_dev *dev;
4662
4663 list_for_each_entry(dev, &bus->devices, bus_list) {
4664 pci_dev_lock(dev);
4665 pci_dev_save_and_disable(dev);
4666 pci_dev_unlock(dev);
4667 if (dev->subordinate)
4668 pci_bus_save_and_disable(dev->subordinate);
4669 }
4670}
4671
4672/*
4673 * Restore devices from top of the tree down - parent bridges need to be
4674 * restored before we can get to subordinate devices.
4675 */
4676static void pci_bus_restore(struct pci_bus *bus)
4677{
4678 struct pci_dev *dev;
4679
4680 list_for_each_entry(dev, &bus->devices, bus_list) {
4681 pci_dev_lock(dev);
4682 pci_dev_restore(dev);
4683 pci_dev_unlock(dev);
4684 if (dev->subordinate)
4685 pci_bus_restore(dev->subordinate);
4686 }
4687}
4688
4689/* Save and disable devices from the top of the tree down */
4690static void pci_slot_save_and_disable(struct pci_slot *slot)
4691{
4692 struct pci_dev *dev;
4693
4694 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
4695 if (!dev->slot || dev->slot != slot)
4696 continue;
4697 pci_dev_save_and_disable(dev);
4698 if (dev->subordinate)
4699 pci_bus_save_and_disable(dev->subordinate);
4700 }
4701}
4702
4703/*
4704 * Restore devices from top of the tree down - parent bridges need to be
4705 * restored before we can get to subordinate devices.
4706 */
4707static void pci_slot_restore(struct pci_slot *slot)
4708{
4709 struct pci_dev *dev;
4710
4711 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
4712 if (!dev->slot || dev->slot != slot)
4713 continue;
4714 pci_dev_lock(dev);
4715 pci_dev_restore(dev);
4716 pci_dev_unlock(dev);
4717 if (dev->subordinate)
4718 pci_bus_restore(dev->subordinate);
4719 }
4720}
4721
4722static int pci_slot_reset(struct pci_slot *slot, int probe)
4723{
4724 int rc;
4725
4726 if (!slot || !pci_slot_resetable(slot))
4727 return -ENOTTY;
4728
4729 if (!probe)
4730 pci_slot_lock(slot);
4731
4732 might_sleep();
4733
4734 rc = pci_reset_hotplug_slot(slot->hotplug, probe);
4735
4736 if (!probe)
4737 pci_slot_unlock(slot);
4738
4739 return rc;
4740}
4741
4742/**
4743 * pci_probe_reset_slot - probe whether a PCI slot can be reset
4744 * @slot: PCI slot to probe
4745 *
4746 * Return 0 if slot can be reset, negative if a slot reset is not supported.
4747 */
4748int pci_probe_reset_slot(struct pci_slot *slot)
4749{
4750 return pci_slot_reset(slot, 1);
4751}
4752EXPORT_SYMBOL_GPL(pci_probe_reset_slot);
4753
4754/**
4755 * pci_reset_slot - reset a PCI slot
4756 * @slot: PCI slot to reset
4757 *
4758 * A PCI bus may host multiple slots, each slot may support a reset mechanism
4759 * independent of other slots. For instance, some slots may support slot power
4760 * control. In the case of a 1:1 bus to slot architecture, this function may
4761 * wrap the bus reset to avoid spurious slot related events such as hotplug.
4762 * Generally a slot reset should be attempted before a bus reset. All of the
4763 * function of the slot and any subordinate buses behind the slot are reset
4764 * through this function. PCI config space of all devices in the slot and
4765 * behind the slot is saved before and restored after reset.
4766 *
4767 * Return 0 on success, non-zero on error.
4768 */
4769int pci_reset_slot(struct pci_slot *slot)
4770{
4771 int rc;
4772
4773 rc = pci_slot_reset(slot, 1);
4774 if (rc)
4775 return rc;
4776
4777 pci_slot_save_and_disable(slot);
4778
4779 rc = pci_slot_reset(slot, 0);
4780
4781 pci_slot_restore(slot);
4782
4783 return rc;
4784}
4785EXPORT_SYMBOL_GPL(pci_reset_slot);
4786
4787/**
4788 * pci_try_reset_slot - Try to reset a PCI slot
4789 * @slot: PCI slot to reset
4790 *
4791 * Same as above except return -EAGAIN if the slot cannot be locked
4792 */
4793int pci_try_reset_slot(struct pci_slot *slot)
4794{
4795 int rc;
4796
4797 rc = pci_slot_reset(slot, 1);
4798 if (rc)
4799 return rc;
4800
4801 pci_slot_save_and_disable(slot);
4802
4803 if (pci_slot_trylock(slot)) {
4804 might_sleep();
4805 rc = pci_reset_hotplug_slot(slot->hotplug, 0);
4806 pci_slot_unlock(slot);
4807 } else
4808 rc = -EAGAIN;
4809
4810 pci_slot_restore(slot);
4811
4812 return rc;
4813}
4814EXPORT_SYMBOL_GPL(pci_try_reset_slot);
4815
4816static int pci_bus_reset(struct pci_bus *bus, int probe)
4817{
4818 if (!bus->self || !pci_bus_resetable(bus))
4819 return -ENOTTY;
4820
4821 if (probe)
4822 return 0;
4823
4824 pci_bus_lock(bus);
4825
4826 might_sleep();
4827
4828 pci_reset_bridge_secondary_bus(bus->self);
4829
4830 pci_bus_unlock(bus);
4831
4832 return 0;
4833}
4834
4835/**
4836 * pci_probe_reset_bus - probe whether a PCI bus can be reset
4837 * @bus: PCI bus to probe
4838 *
4839 * Return 0 if bus can be reset, negative if a bus reset is not supported.
4840 */
4841int pci_probe_reset_bus(struct pci_bus *bus)
4842{
4843 return pci_bus_reset(bus, 1);
4844}
4845EXPORT_SYMBOL_GPL(pci_probe_reset_bus);
4846
4847/**
4848 * pci_reset_bus - reset a PCI bus
4849 * @bus: top level PCI bus to reset
4850 *
4851 * Do a bus reset on the given bus and any subordinate buses, saving
4852 * and restoring state of all devices.
4853 *
4854 * Return 0 on success, non-zero on error.
4855 */
4856int pci_reset_bus(struct pci_bus *bus)
4857{
4858 int rc;
4859
4860 rc = pci_bus_reset(bus, 1);
4861 if (rc)
4862 return rc;
4863
4864 pci_bus_save_and_disable(bus);
4865
4866 rc = pci_bus_reset(bus, 0);
4867
4868 pci_bus_restore(bus);
4869
4870 return rc;
4871}
4872EXPORT_SYMBOL_GPL(pci_reset_bus);
4873
4874/**
4875 * pci_try_reset_bus - Try to reset a PCI bus
4876 * @bus: top level PCI bus to reset
4877 *
4878 * Same as above except return -EAGAIN if the bus cannot be locked
4879 */
4880int pci_try_reset_bus(struct pci_bus *bus)
4881{
4882 int rc;
4883
4884 rc = pci_bus_reset(bus, 1);
4885 if (rc)
4886 return rc;
4887
4888 pci_bus_save_and_disable(bus);
4889
4890 if (pci_bus_trylock(bus)) {
4891 might_sleep();
4892 pci_reset_bridge_secondary_bus(bus->self);
4893 pci_bus_unlock(bus);
4894 } else
4895 rc = -EAGAIN;
4896
4897 pci_bus_restore(bus);
4898
4899 return rc;
4900}
4901EXPORT_SYMBOL_GPL(pci_try_reset_bus);
4902
4903/**
4904 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
4905 * @dev: PCI device to query
4906 *
4907 * Returns mmrbc: maximum designed memory read count in bytes
4908 * or appropriate error value.
4909 */
4910int pcix_get_max_mmrbc(struct pci_dev *dev)
4911{
4912 int cap;
4913 u32 stat;
4914
4915 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
4916 if (!cap)
4917 return -EINVAL;
4918
4919 if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
4920 return -EINVAL;
4921
4922 return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21);
4923}
4924EXPORT_SYMBOL(pcix_get_max_mmrbc);
4925
4926/**
4927 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
4928 * @dev: PCI device to query
4929 *
4930 * Returns mmrbc: maximum memory read count in bytes
4931 * or appropriate error value.
4932 */
4933int pcix_get_mmrbc(struct pci_dev *dev)
4934{
4935 int cap;
4936 u16 cmd;
4937
4938 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
4939 if (!cap)
4940 return -EINVAL;
4941
4942 if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
4943 return -EINVAL;
4944
4945 return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
4946}
4947EXPORT_SYMBOL(pcix_get_mmrbc);
4948
4949/**
4950 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
4951 * @dev: PCI device to query
4952 * @mmrbc: maximum memory read count in bytes
4953 * valid values are 512, 1024, 2048, 4096
4954 *
4955 * If possible sets maximum memory read byte count, some bridges have erratas
4956 * that prevent this.
4957 */
4958int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
4959{
4960 int cap;
4961 u32 stat, v, o;
4962 u16 cmd;
4963
4964 if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
4965 return -EINVAL;
4966
4967 v = ffs(mmrbc) - 10;
4968
4969 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
4970 if (!cap)
4971 return -EINVAL;
4972
4973 if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
4974 return -EINVAL;
4975
4976 if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
4977 return -E2BIG;
4978
4979 if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
4980 return -EINVAL;
4981
4982 o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
4983 if (o != v) {
4984 if (v > o && (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
4985 return -EIO;
4986
4987 cmd &= ~PCI_X_CMD_MAX_READ;
4988 cmd |= v << 2;
4989 if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd))
4990 return -EIO;
4991 }
4992 return 0;
4993}
4994EXPORT_SYMBOL(pcix_set_mmrbc);
4995
4996/**
4997 * pcie_get_readrq - get PCI Express read request size
4998 * @dev: PCI device to query
4999 *
5000 * Returns maximum memory read request in bytes
5001 * or appropriate error value.
5002 */
5003int pcie_get_readrq(struct pci_dev *dev)
5004{
5005 u16 ctl;
5006
5007 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
5008
5009 return 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
5010}
5011EXPORT_SYMBOL(pcie_get_readrq);
5012
5013/**
5014 * pcie_set_readrq - set PCI Express maximum memory read request
5015 * @dev: PCI device to query
5016 * @rq: maximum memory read count in bytes
5017 * valid values are 128, 256, 512, 1024, 2048, 4096
5018 *
5019 * If possible sets maximum memory read request in bytes
5020 */
5021int pcie_set_readrq(struct pci_dev *dev, int rq)
5022{
5023 u16 v;
5024
5025 if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
5026 return -EINVAL;
5027
5028 /*
5029 * If using the "performance" PCIe config, we clamp the
5030 * read rq size to the max packet size to prevent the
5031 * host bridge generating requests larger than we can
5032 * cope with
5033 */
5034 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
5035 int mps = pcie_get_mps(dev);
5036
5037 if (mps < rq)
5038 rq = mps;
5039 }
5040
5041 v = (ffs(rq) - 8) << 12;
5042
5043 return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
5044 PCI_EXP_DEVCTL_READRQ, v);
5045}
5046EXPORT_SYMBOL(pcie_set_readrq);
5047
5048/**
5049 * pcie_get_mps - get PCI Express maximum payload size
5050 * @dev: PCI device to query
5051 *
5052 * Returns maximum payload size in bytes
5053 */
5054int pcie_get_mps(struct pci_dev *dev)
5055{
5056 u16 ctl;
5057
5058 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
5059
5060 return 128 << ((ctl & PCI_EXP_DEVCTL_PAYLOAD) >> 5);
5061}
5062EXPORT_SYMBOL(pcie_get_mps);
5063
5064/**
5065 * pcie_set_mps - set PCI Express maximum payload size
5066 * @dev: PCI device to query
5067 * @mps: maximum payload size in bytes
5068 * valid values are 128, 256, 512, 1024, 2048, 4096
5069 *
5070 * If possible sets maximum payload size
5071 */
5072int pcie_set_mps(struct pci_dev *dev, int mps)
5073{
5074 u16 v;
5075
5076 if (mps < 128 || mps > 4096 || !is_power_of_2(mps))
5077 return -EINVAL;
5078
5079 v = ffs(mps) - 8;
5080 if (v > dev->pcie_mpss)
5081 return -EINVAL;
5082 v <<= 5;
5083
5084 return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
5085 PCI_EXP_DEVCTL_PAYLOAD, v);
5086}
5087EXPORT_SYMBOL(pcie_set_mps);
5088
5089/**
5090 * pcie_get_minimum_link - determine minimum link settings of a PCI device
5091 * @dev: PCI device to query
5092 * @speed: storage for minimum speed
5093 * @width: storage for minimum width
5094 *
5095 * This function will walk up the PCI device chain and determine the minimum
5096 * link width and speed of the device.
5097 */
5098int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed,
5099 enum pcie_link_width *width)
5100{
5101 int ret;
5102
5103 *speed = PCI_SPEED_UNKNOWN;
5104 *width = PCIE_LNK_WIDTH_UNKNOWN;
5105
5106 while (dev) {
5107 u16 lnksta;
5108 enum pci_bus_speed next_speed;
5109 enum pcie_link_width next_width;
5110
5111 ret = pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);
5112 if (ret)
5113 return ret;
5114
5115 next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
5116 next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >>
5117 PCI_EXP_LNKSTA_NLW_SHIFT;
5118
5119 if (next_speed < *speed)
5120 *speed = next_speed;
5121
5122 if (next_width < *width)
5123 *width = next_width;
5124
5125 dev = dev->bus->self;
5126 }
5127
5128 return 0;
5129}
5130EXPORT_SYMBOL(pcie_get_minimum_link);
5131
5132/**
5133 * pcie_bandwidth_available - determine minimum link settings of a PCIe
5134 * device and its bandwidth limitation
5135 * @dev: PCI device to query
5136 * @limiting_dev: storage for device causing the bandwidth limitation
5137 * @speed: storage for speed of limiting device
5138 * @width: storage for width of limiting device
5139 *
5140 * Walk up the PCI device chain and find the point where the minimum
5141 * bandwidth is available. Return the bandwidth available there and (if
5142 * limiting_dev, speed, and width pointers are supplied) information about
5143 * that point. The bandwidth returned is in Mb/s, i.e., megabits/second of
5144 * raw bandwidth.
5145 */
5146u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev,
5147 enum pci_bus_speed *speed,
5148 enum pcie_link_width *width)
5149{
5150 u16 lnksta;
5151 enum pci_bus_speed next_speed;
5152 enum pcie_link_width next_width;
5153 u32 bw, next_bw;
5154
5155 if (speed)
5156 *speed = PCI_SPEED_UNKNOWN;
5157 if (width)
5158 *width = PCIE_LNK_WIDTH_UNKNOWN;
5159
5160 bw = 0;
5161
5162 while (dev) {
5163 pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);
5164
5165 next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
5166 next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >>
5167 PCI_EXP_LNKSTA_NLW_SHIFT;
5168
5169 next_bw = next_width * PCIE_SPEED2MBS_ENC(next_speed);
5170
5171 /* Check if current device limits the total bandwidth */
5172 if (!bw || next_bw <= bw) {
5173 bw = next_bw;
5174
5175 if (limiting_dev)
5176 *limiting_dev = dev;
5177 if (speed)
5178 *speed = next_speed;
5179 if (width)
5180 *width = next_width;
5181 }
5182
5183 dev = pci_upstream_bridge(dev);
5184 }
5185
5186 return bw;
5187}
5188EXPORT_SYMBOL(pcie_bandwidth_available);
5189
5190/**
5191 * pcie_get_speed_cap - query for the PCI device's link speed capability
5192 * @dev: PCI device to query
5193 *
5194 * Query the PCI device speed capability. Return the maximum link speed
5195 * supported by the device.
5196 */
5197enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev)
5198{
5199 u32 lnkcap2, lnkcap;
5200
5201 /*
5202 * PCIe r4.0 sec 7.5.3.18 recommends using the Supported Link
5203 * Speeds Vector in Link Capabilities 2 when supported, falling
5204 * back to Max Link Speed in Link Capabilities otherwise.
5205 */
5206 pcie_capability_read_dword(dev, PCI_EXP_LNKCAP2, &lnkcap2);
5207 if (lnkcap2) { /* PCIe r3.0-compliant */
5208 if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_16_0GB)
5209 return PCIE_SPEED_16_0GT;
5210 else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_8_0GB)
5211 return PCIE_SPEED_8_0GT;
5212 else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_5_0GB)
5213 return PCIE_SPEED_5_0GT;
5214 else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_2_5GB)
5215 return PCIE_SPEED_2_5GT;
5216 return PCI_SPEED_UNKNOWN;
5217 }
5218
5219 pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);
5220 if (lnkcap) {
5221 if (lnkcap & PCI_EXP_LNKCAP_SLS_16_0GB)
5222 return PCIE_SPEED_16_0GT;
5223 else if (lnkcap & PCI_EXP_LNKCAP_SLS_8_0GB)
5224 return PCIE_SPEED_8_0GT;
5225 else if (lnkcap & PCI_EXP_LNKCAP_SLS_5_0GB)
5226 return PCIE_SPEED_5_0GT;
5227 else if (lnkcap & PCI_EXP_LNKCAP_SLS_2_5GB)
5228 return PCIE_SPEED_2_5GT;
5229 }
5230
5231 return PCI_SPEED_UNKNOWN;
5232}
5233
5234/**
5235 * pcie_get_width_cap - query for the PCI device's link width capability
5236 * @dev: PCI device to query
5237 *
5238 * Query the PCI device width capability. Return the maximum link width
5239 * supported by the device.
5240 */
5241enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev)
5242{
5243 u32 lnkcap;
5244
5245 pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);
5246 if (lnkcap)
5247 return (lnkcap & PCI_EXP_LNKCAP_MLW) >> 4;
5248
5249 return PCIE_LNK_WIDTH_UNKNOWN;
5250}
5251
5252/**
5253 * pcie_bandwidth_capable - calculate a PCI device's link bandwidth capability
5254 * @dev: PCI device
5255 * @speed: storage for link speed
5256 * @width: storage for link width
5257 *
5258 * Calculate a PCI device's link bandwidth by querying for its link speed
5259 * and width, multiplying them, and applying encoding overhead. The result
5260 * is in Mb/s, i.e., megabits/second of raw bandwidth.
5261 */
5262u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed,
5263 enum pcie_link_width *width)
5264{
5265 *speed = pcie_get_speed_cap(dev);
5266 *width = pcie_get_width_cap(dev);
5267
5268 if (*speed == PCI_SPEED_UNKNOWN || *width == PCIE_LNK_WIDTH_UNKNOWN)
5269 return 0;
5270
5271 return *width * PCIE_SPEED2MBS_ENC(*speed);
5272}
5273
5274/**
5275 * pcie_print_link_status - Report the PCI device's link speed and width
5276 * @dev: PCI device to query
5277 *
5278 * Report the available bandwidth at the device. If this is less than the
5279 * device is capable of, report the device's maximum possible bandwidth and
5280 * the upstream link that limits its performance to less than that.
5281 */
5282void pcie_print_link_status(struct pci_dev *dev)
5283{
5284 enum pcie_link_width width, width_cap;
5285 enum pci_bus_speed speed, speed_cap;
5286 struct pci_dev *limiting_dev = NULL;
5287 u32 bw_avail, bw_cap;
5288
5289 bw_cap = pcie_bandwidth_capable(dev, &speed_cap, &width_cap);
5290 bw_avail = pcie_bandwidth_available(dev, &limiting_dev, &speed, &width);
5291
5292 if (bw_avail >= bw_cap)
5293 pci_info(dev, "%u.%03u Gb/s available PCIe bandwidth (%s x%d link)\n",
5294 bw_cap / 1000, bw_cap % 1000,
5295 PCIE_SPEED2STR(speed_cap), width_cap);
5296 else
5297 pci_info(dev, "%u.%03u Gb/s available PCIe bandwidth, limited by %s x%d link at %s (capable of %u.%03u Gb/s with %s x%d link)\n",
5298 bw_avail / 1000, bw_avail % 1000,
5299 PCIE_SPEED2STR(speed), width,
5300 limiting_dev ? pci_name(limiting_dev) : "<unknown>",
5301 bw_cap / 1000, bw_cap % 1000,
5302 PCIE_SPEED2STR(speed_cap), width_cap);
5303}
5304EXPORT_SYMBOL(pcie_print_link_status);
5305
5306/**
5307 * pci_select_bars - Make BAR mask from the type of resource
5308 * @dev: the PCI device for which BAR mask is made
5309 * @flags: resource type mask to be selected
5310 *
5311 * This helper routine makes bar mask from the type of resource.
5312 */
5313int pci_select_bars(struct pci_dev *dev, unsigned long flags)
5314{
5315 int i, bars = 0;
5316 for (i = 0; i < PCI_NUM_RESOURCES; i++)
5317 if (pci_resource_flags(dev, i) & flags)
5318 bars |= (1 << i);
5319 return bars;
5320}
5321EXPORT_SYMBOL(pci_select_bars);
5322
5323/* Some architectures require additional programming to enable VGA */
5324static arch_set_vga_state_t arch_set_vga_state;
5325
5326void __init pci_register_set_vga_state(arch_set_vga_state_t func)
5327{
5328 arch_set_vga_state = func; /* NULL disables */
5329}
5330
5331static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode,
5332 unsigned int command_bits, u32 flags)
5333{
5334 if (arch_set_vga_state)
5335 return arch_set_vga_state(dev, decode, command_bits,
5336 flags);
5337 return 0;
5338}
5339
5340/**
5341 * pci_set_vga_state - set VGA decode state on device and parents if requested
5342 * @dev: the PCI device
5343 * @decode: true = enable decoding, false = disable decoding
5344 * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
5345 * @flags: traverse ancestors and change bridges
5346 * CHANGE_BRIDGE_ONLY / CHANGE_BRIDGE
5347 */
5348int pci_set_vga_state(struct pci_dev *dev, bool decode,
5349 unsigned int command_bits, u32 flags)
5350{
5351 struct pci_bus *bus;
5352 struct pci_dev *bridge;
5353 u16 cmd;
5354 int rc;
5355
5356 WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) && (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY)));
5357
5358 /* ARCH specific VGA enables */
5359 rc = pci_set_vga_state_arch(dev, decode, command_bits, flags);
5360 if (rc)
5361 return rc;
5362
5363 if (flags & PCI_VGA_STATE_CHANGE_DECODES) {
5364 pci_read_config_word(dev, PCI_COMMAND, &cmd);
5365 if (decode == true)
5366 cmd |= command_bits;
5367 else
5368 cmd &= ~command_bits;
5369 pci_write_config_word(dev, PCI_COMMAND, cmd);
5370 }
5371
5372 if (!(flags & PCI_VGA_STATE_CHANGE_BRIDGE))
5373 return 0;
5374
5375 bus = dev->bus;
5376 while (bus) {
5377 bridge = bus->self;
5378 if (bridge) {
5379 pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
5380 &cmd);
5381 if (decode == true)
5382 cmd |= PCI_BRIDGE_CTL_VGA;
5383 else
5384 cmd &= ~PCI_BRIDGE_CTL_VGA;
5385 pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
5386 cmd);
5387 }
5388 bus = bus->parent;
5389 }
5390 return 0;
5391}
5392
5393/**
5394 * pci_add_dma_alias - Add a DMA devfn alias for a device
5395 * @dev: the PCI device for which alias is added
5396 * @devfn: alias slot and function
5397 *
5398 * This helper encodes 8-bit devfn as bit number in dma_alias_mask.
5399 * It should be called early, preferably as PCI fixup header quirk.
5400 */
5401void pci_add_dma_alias(struct pci_dev *dev, u8 devfn)
5402{
5403 if (!dev->dma_alias_mask)
5404 dev->dma_alias_mask = kcalloc(BITS_TO_LONGS(U8_MAX),
5405 sizeof(long), GFP_KERNEL);
5406 if (!dev->dma_alias_mask) {
5407 pci_warn(dev, "Unable to allocate DMA alias mask\n");
5408 return;
5409 }
5410
5411 set_bit(devfn, dev->dma_alias_mask);
5412 pci_info(dev, "Enabling fixed DMA alias to %02x.%d\n",
5413 PCI_SLOT(devfn), PCI_FUNC(devfn));
5414}
5415
5416bool pci_devs_are_dma_aliases(struct pci_dev *dev1, struct pci_dev *dev2)
5417{
5418 return (dev1->dma_alias_mask &&
5419 test_bit(dev2->devfn, dev1->dma_alias_mask)) ||
5420 (dev2->dma_alias_mask &&
5421 test_bit(dev1->devfn, dev2->dma_alias_mask));
5422}
5423
5424bool pci_device_is_present(struct pci_dev *pdev)
5425{
5426 u32 v;
5427
5428 if (pci_dev_is_disconnected(pdev))
5429 return false;
5430 return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0);
5431}
5432EXPORT_SYMBOL_GPL(pci_device_is_present);
5433
5434void pci_ignore_hotplug(struct pci_dev *dev)
5435{
5436 struct pci_dev *bridge = dev->bus->self;
5437
5438 dev->ignore_hotplug = 1;
5439 /* Propagate the "ignore hotplug" setting to the parent bridge. */
5440 if (bridge)
5441 bridge->ignore_hotplug = 1;
5442}
5443EXPORT_SYMBOL_GPL(pci_ignore_hotplug);
5444
5445resource_size_t __weak pcibios_default_alignment(void)
5446{
5447 return 0;
5448}
5449
5450#define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
5451static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
5452static DEFINE_SPINLOCK(resource_alignment_lock);
5453
5454/**
5455 * pci_specified_resource_alignment - get resource alignment specified by user.
5456 * @dev: the PCI device to get
5457 * @resize: whether or not to change resources' size when reassigning alignment
5458 *
5459 * RETURNS: Resource alignment if it is specified.
5460 * Zero if it is not specified.
5461 */
5462static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev,
5463 bool *resize)
5464{
5465 int seg, bus, slot, func, align_order, count;
5466 unsigned short vendor, device, subsystem_vendor, subsystem_device;
5467 resource_size_t align = pcibios_default_alignment();
5468 char *p;
5469
5470 spin_lock(&resource_alignment_lock);
5471 p = resource_alignment_param;
5472 if (!*p && !align)
5473 goto out;
5474 if (pci_has_flag(PCI_PROBE_ONLY)) {
5475 align = 0;
5476 pr_info_once("PCI: Ignoring requested alignments (PCI_PROBE_ONLY)\n");
5477 goto out;
5478 }
5479
5480 while (*p) {
5481 count = 0;
5482 if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
5483 p[count] == '@') {
5484 p += count + 1;
5485 } else {
5486 align_order = -1;
5487 }
5488 if (strncmp(p, "pci:", 4) == 0) {
5489 /* PCI vendor/device (subvendor/subdevice) ids are specified */
5490 p += 4;
5491 if (sscanf(p, "%hx:%hx:%hx:%hx%n",
5492 &vendor, &device, &subsystem_vendor, &subsystem_device, &count) != 4) {
5493 if (sscanf(p, "%hx:%hx%n", &vendor, &device, &count) != 2) {
5494 printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: pci:%s\n",
5495 p);
5496 break;
5497 }
5498 subsystem_vendor = subsystem_device = 0;
5499 }
5500 p += count;
5501 if ((!vendor || (vendor == dev->vendor)) &&
5502 (!device || (device == dev->device)) &&
5503 (!subsystem_vendor || (subsystem_vendor == dev->subsystem_vendor)) &&
5504 (!subsystem_device || (subsystem_device == dev->subsystem_device))) {
5505 *resize = true;
5506 if (align_order == -1)
5507 align = PAGE_SIZE;
5508 else
5509 align = 1 << align_order;
5510 /* Found */
5511 break;
5512 }
5513 }
5514 else {
5515 if (sscanf(p, "%x:%x:%x.%x%n",
5516 &seg, &bus, &slot, &func, &count) != 4) {
5517 seg = 0;
5518 if (sscanf(p, "%x:%x.%x%n",
5519 &bus, &slot, &func, &count) != 3) {
5520 /* Invalid format */
5521 printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
5522 p);
5523 break;
5524 }
5525 }
5526 p += count;
5527 if (seg == pci_domain_nr(dev->bus) &&
5528 bus == dev->bus->number &&
5529 slot == PCI_SLOT(dev->devfn) &&
5530 func == PCI_FUNC(dev->devfn)) {
5531 *resize = true;
5532 if (align_order == -1)
5533 align = PAGE_SIZE;
5534 else
5535 align = 1 << align_order;
5536 /* Found */
5537 break;
5538 }
5539 }
5540 if (*p != ';' && *p != ',') {
5541 /* End of param or invalid format */
5542 break;
5543 }
5544 p++;
5545 }
5546out:
5547 spin_unlock(&resource_alignment_lock);
5548 return align;
5549}
5550
5551static void pci_request_resource_alignment(struct pci_dev *dev, int bar,
5552 resource_size_t align, bool resize)
5553{
5554 struct resource *r = &dev->resource[bar];
5555 resource_size_t size;
5556
5557 if (!(r->flags & IORESOURCE_MEM))
5558 return;
5559
5560 if (r->flags & IORESOURCE_PCI_FIXED) {
5561 pci_info(dev, "BAR%d %pR: ignoring requested alignment %#llx\n",
5562 bar, r, (unsigned long long)align);
5563 return;
5564 }
5565
5566 size = resource_size(r);
5567 if (size >= align)
5568 return;
5569
5570 /*
5571 * Increase the alignment of the resource. There are two ways we
5572 * can do this:
5573 *
5574 * 1) Increase the size of the resource. BARs are aligned on their
5575 * size, so when we reallocate space for this resource, we'll
5576 * allocate it with the larger alignment. This also prevents
5577 * assignment of any other BARs inside the alignment region, so
5578 * if we're requesting page alignment, this means no other BARs
5579 * will share the page.
5580 *
5581 * The disadvantage is that this makes the resource larger than
5582 * the hardware BAR, which may break drivers that compute things
5583 * based on the resource size, e.g., to find registers at a
5584 * fixed offset before the end of the BAR.
5585 *
5586 * 2) Retain the resource size, but use IORESOURCE_STARTALIGN and
5587 * set r->start to the desired alignment. By itself this
5588 * doesn't prevent other BARs being put inside the alignment
5589 * region, but if we realign *every* resource of every device in
5590 * the system, none of them will share an alignment region.
5591 *
5592 * When the user has requested alignment for only some devices via
5593 * the "pci=resource_alignment" argument, "resize" is true and we
5594 * use the first method. Otherwise we assume we're aligning all
5595 * devices and we use the second.
5596 */
5597
5598 pci_info(dev, "BAR%d %pR: requesting alignment to %#llx\n",
5599 bar, r, (unsigned long long)align);
5600
5601 if (resize) {
5602 r->start = 0;
5603 r->end = align - 1;
5604 } else {
5605 r->flags &= ~IORESOURCE_SIZEALIGN;
5606 r->flags |= IORESOURCE_STARTALIGN;
5607 r->start = align;
5608 r->end = r->start + size - 1;
5609 }
5610 r->flags |= IORESOURCE_UNSET;
5611}
5612
5613/*
5614 * This function disables memory decoding and releases memory resources
5615 * of the device specified by kernel's boot parameter 'pci=resource_alignment='.
5616 * It also rounds up size to specified alignment.
5617 * Later on, the kernel will assign page-aligned memory resource back
5618 * to the device.
5619 */
5620void pci_reassigndev_resource_alignment(struct pci_dev *dev)
5621{
5622 int i;
5623 struct resource *r;
5624 resource_size_t align;
5625 u16 command;
5626 bool resize = false;
5627
5628 /*
5629 * VF BARs are read-only zero according to SR-IOV spec r1.1, sec
5630 * 3.4.1.11. Their resources are allocated from the space
5631 * described by the VF BARx register in the PF's SR-IOV capability.
5632 * We can't influence their alignment here.
5633 */
5634 if (dev->is_virtfn)
5635 return;
5636
5637 /* check if specified PCI is target device to reassign */
5638 align = pci_specified_resource_alignment(dev, &resize);
5639 if (!align)
5640 return;
5641
5642 if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL &&
5643 (dev->class >> 8) == PCI_CLASS_BRIDGE_HOST) {
5644 pci_warn(dev, "Can't reassign resources to host bridge\n");
5645 return;
5646 }
5647
5648 pci_read_config_word(dev, PCI_COMMAND, &command);
5649 command &= ~PCI_COMMAND_MEMORY;
5650 pci_write_config_word(dev, PCI_COMMAND, command);
5651
5652 for (i = 0; i <= PCI_ROM_RESOURCE; i++)
5653 pci_request_resource_alignment(dev, i, align, resize);
5654
5655 /*
5656 * Need to disable bridge's resource window,
5657 * to enable the kernel to reassign new resource
5658 * window later on.
5659 */
5660 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
5661 (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
5662 for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) {
5663 r = &dev->resource[i];
5664 if (!(r->flags & IORESOURCE_MEM))
5665 continue;
5666 r->flags |= IORESOURCE_UNSET;
5667 r->end = resource_size(r) - 1;
5668 r->start = 0;
5669 }
5670 pci_disable_bridge_window(dev);
5671 }
5672}
5673
5674static ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
5675{
5676 if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
5677 count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
5678 spin_lock(&resource_alignment_lock);
5679 strncpy(resource_alignment_param, buf, count);
5680 resource_alignment_param[count] = '\0';
5681 spin_unlock(&resource_alignment_lock);
5682 return count;
5683}
5684
5685static ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
5686{
5687 size_t count;
5688 spin_lock(&resource_alignment_lock);
5689 count = snprintf(buf, size, "%s", resource_alignment_param);
5690 spin_unlock(&resource_alignment_lock);
5691 return count;
5692}
5693
5694static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
5695{
5696 return pci_get_resource_alignment_param(buf, PAGE_SIZE);
5697}
5698
5699static ssize_t pci_resource_alignment_store(struct bus_type *bus,
5700 const char *buf, size_t count)
5701{
5702 return pci_set_resource_alignment_param(buf, count);
5703}
5704
5705static BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
5706 pci_resource_alignment_store);
5707
5708static int __init pci_resource_alignment_sysfs_init(void)
5709{
5710 return bus_create_file(&pci_bus_type,
5711 &bus_attr_resource_alignment);
5712}
5713late_initcall(pci_resource_alignment_sysfs_init);
5714
5715static void pci_no_domains(void)
5716{
5717#ifdef CONFIG_PCI_DOMAINS
5718 pci_domains_supported = 0;
5719#endif
5720}
5721
5722#ifdef CONFIG_PCI_DOMAINS
5723static atomic_t __domain_nr = ATOMIC_INIT(-1);
5724
5725int pci_get_new_domain_nr(void)
5726{
5727 return atomic_inc_return(&__domain_nr);
5728}
5729
5730#ifdef CONFIG_PCI_DOMAINS_GENERIC
5731static int of_pci_bus_find_domain_nr(struct device *parent)
5732{
5733 static int use_dt_domains = -1;
5734 int domain = -1;
5735
5736 if (parent)
5737 domain = of_get_pci_domain_nr(parent->of_node);
5738 /*
5739 * Check DT domain and use_dt_domains values.
5740 *
5741 * If DT domain property is valid (domain >= 0) and
5742 * use_dt_domains != 0, the DT assignment is valid since this means
5743 * we have not previously allocated a domain number by using
5744 * pci_get_new_domain_nr(); we should also update use_dt_domains to
5745 * 1, to indicate that we have just assigned a domain number from
5746 * DT.
5747 *
5748 * If DT domain property value is not valid (ie domain < 0), and we
5749 * have not previously assigned a domain number from DT
5750 * (use_dt_domains != 1) we should assign a domain number by
5751 * using the:
5752 *
5753 * pci_get_new_domain_nr()
5754 *
5755 * API and update the use_dt_domains value to keep track of method we
5756 * are using to assign domain numbers (use_dt_domains = 0).
5757 *
5758 * All other combinations imply we have a platform that is trying
5759 * to mix domain numbers obtained from DT and pci_get_new_domain_nr(),
5760 * which is a recipe for domain mishandling and it is prevented by
5761 * invalidating the domain value (domain = -1) and printing a
5762 * corresponding error.
5763 */
5764 if (domain >= 0 && use_dt_domains) {
5765 use_dt_domains = 1;
5766 } else if (domain < 0 && use_dt_domains != 1) {
5767 use_dt_domains = 0;
5768 domain = pci_get_new_domain_nr();
5769 } else {
5770 if (parent)
5771 pr_err("Node %pOF has ", parent->of_node);
5772 pr_err("Inconsistent \"linux,pci-domain\" property in DT\n");
5773 domain = -1;
5774 }
5775
5776 return domain;
5777}
5778
5779int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent)
5780{
5781 return acpi_disabled ? of_pci_bus_find_domain_nr(parent) :
5782 acpi_pci_bus_find_domain_nr(bus);
5783}
5784#endif
5785#endif
5786
5787/**
5788 * pci_ext_cfg_avail - can we access extended PCI config space?
5789 *
5790 * Returns 1 if we can access PCI extended config space (offsets
5791 * greater than 0xff). This is the default implementation. Architecture
5792 * implementations can override this.
5793 */
5794int __weak pci_ext_cfg_avail(void)
5795{
5796 return 1;
5797}
5798
5799void __weak pci_fixup_cardbus(struct pci_bus *bus)
5800{
5801}
5802EXPORT_SYMBOL(pci_fixup_cardbus);
5803
5804static int __init pci_setup(char *str)
5805{
5806 while (str) {
5807 char *k = strchr(str, ',');
5808 if (k)
5809 *k++ = 0;
5810 if (*str && (str = pcibios_setup(str)) && *str) {
5811 if (!strcmp(str, "nomsi")) {
5812 pci_no_msi();
5813 } else if (!strcmp(str, "noaer")) {
5814 pci_no_aer();
5815 } else if (!strncmp(str, "realloc=", 8)) {
5816 pci_realloc_get_opt(str + 8);
5817 } else if (!strncmp(str, "realloc", 7)) {
5818 pci_realloc_get_opt("on");
5819 } else if (!strcmp(str, "nodomains")) {
5820 pci_no_domains();
5821 } else if (!strncmp(str, "noari", 5)) {
5822 pcie_ari_disabled = true;
5823 } else if (!strncmp(str, "cbiosize=", 9)) {
5824 pci_cardbus_io_size = memparse(str + 9, &str);
5825 } else if (!strncmp(str, "cbmemsize=", 10)) {
5826 pci_cardbus_mem_size = memparse(str + 10, &str);
5827 } else if (!strncmp(str, "resource_alignment=", 19)) {
5828 pci_set_resource_alignment_param(str + 19,
5829 strlen(str + 19));
5830 } else if (!strncmp(str, "ecrc=", 5)) {
5831 pcie_ecrc_get_policy(str + 5);
5832 } else if (!strncmp(str, "hpiosize=", 9)) {
5833 pci_hotplug_io_size = memparse(str + 9, &str);
5834 } else if (!strncmp(str, "hpmemsize=", 10)) {
5835 pci_hotplug_mem_size = memparse(str + 10, &str);
5836 } else if (!strncmp(str, "hpbussize=", 10)) {
5837 pci_hotplug_bus_size =
5838 simple_strtoul(str + 10, &str, 0);
5839 if (pci_hotplug_bus_size > 0xff)
5840 pci_hotplug_bus_size = DEFAULT_HOTPLUG_BUS_SIZE;
5841 } else if (!strncmp(str, "pcie_bus_tune_off", 17)) {
5842 pcie_bus_config = PCIE_BUS_TUNE_OFF;
5843 } else if (!strncmp(str, "pcie_bus_safe", 13)) {
5844 pcie_bus_config = PCIE_BUS_SAFE;
5845 } else if (!strncmp(str, "pcie_bus_perf", 13)) {
5846 pcie_bus_config = PCIE_BUS_PERFORMANCE;
5847 } else if (!strncmp(str, "pcie_bus_peer2peer", 18)) {
5848 pcie_bus_config = PCIE_BUS_PEER2PEER;
5849 } else if (!strncmp(str, "pcie_scan_all", 13)) {
5850 pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS);
5851 } else {
5852 printk(KERN_ERR "PCI: Unknown option `%s'\n",
5853 str);
5854 }
5855 }
5856 str = k;
5857 }
5858 return 0;
5859}
5860early_param("pci", pci_setup);
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/of.h>
14#include <linux/of_pci.h>
15#include <linux/pci.h>
16#include <linux/pm.h>
17#include <linux/slab.h>
18#include <linux/module.h>
19#include <linux/spinlock.h>
20#include <linux/string.h>
21#include <linux/log2.h>
22#include <linux/pci-aspm.h>
23#include <linux/pm_wakeup.h>
24#include <linux/interrupt.h>
25#include <linux/device.h>
26#include <linux/pm_runtime.h>
27#include <linux/pci_hotplug.h>
28#include <asm/setup.h>
29#include <linux/aer.h>
30#include "pci.h"
31
32const char *pci_power_names[] = {
33 "error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
34};
35EXPORT_SYMBOL_GPL(pci_power_names);
36
37int isa_dma_bridge_buggy;
38EXPORT_SYMBOL(isa_dma_bridge_buggy);
39
40int pci_pci_problems;
41EXPORT_SYMBOL(pci_pci_problems);
42
43unsigned int pci_pm_d3_delay;
44
45static void pci_pme_list_scan(struct work_struct *work);
46
47static LIST_HEAD(pci_pme_list);
48static DEFINE_MUTEX(pci_pme_list_mutex);
49static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan);
50
51struct pci_pme_device {
52 struct list_head list;
53 struct pci_dev *dev;
54};
55
56#define PME_TIMEOUT 1000 /* How long between PME checks */
57
58static void pci_dev_d3_sleep(struct pci_dev *dev)
59{
60 unsigned int delay = dev->d3_delay;
61
62 if (delay < pci_pm_d3_delay)
63 delay = pci_pm_d3_delay;
64
65 msleep(delay);
66}
67
68#ifdef CONFIG_PCI_DOMAINS
69int pci_domains_supported = 1;
70#endif
71
72#define DEFAULT_CARDBUS_IO_SIZE (256)
73#define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
74/* pci=cbmemsize=nnM,cbiosize=nn can override this */
75unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
76unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
77
78#define DEFAULT_HOTPLUG_IO_SIZE (256)
79#define DEFAULT_HOTPLUG_MEM_SIZE (2*1024*1024)
80/* pci=hpmemsize=nnM,hpiosize=nn can override this */
81unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE;
82unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
83
84enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_DEFAULT;
85
86/*
87 * The default CLS is used if arch didn't set CLS explicitly and not
88 * all pci devices agree on the same value. Arch can override either
89 * the dfl or actual value as it sees fit. Don't forget this is
90 * measured in 32-bit words, not bytes.
91 */
92u8 pci_dfl_cache_line_size = L1_CACHE_BYTES >> 2;
93u8 pci_cache_line_size;
94
95/*
96 * If we set up a device for bus mastering, we need to check the latency
97 * timer as certain BIOSes forget to set it properly.
98 */
99unsigned int pcibios_max_latency = 255;
100
101/* If set, the PCIe ARI capability will not be used. */
102static bool pcie_ari_disabled;
103
104/**
105 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
106 * @bus: pointer to PCI bus structure to search
107 *
108 * Given a PCI bus, returns the highest PCI bus number present in the set
109 * including the given PCI bus and its list of child PCI buses.
110 */
111unsigned char pci_bus_max_busnr(struct pci_bus *bus)
112{
113 struct pci_bus *tmp;
114 unsigned char max, n;
115
116 max = bus->busn_res.end;
117 list_for_each_entry(tmp, &bus->children, node) {
118 n = pci_bus_max_busnr(tmp);
119 if (n > max)
120 max = n;
121 }
122 return max;
123}
124EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
125
126#ifdef CONFIG_HAS_IOMEM
127void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
128{
129 struct resource *res = &pdev->resource[bar];
130
131 /*
132 * Make sure the BAR is actually a memory resource, not an IO resource
133 */
134 if (res->flags & IORESOURCE_UNSET || !(res->flags & IORESOURCE_MEM)) {
135 dev_warn(&pdev->dev, "can't ioremap BAR %d: %pR\n", bar, res);
136 return NULL;
137 }
138 return ioremap_nocache(res->start, resource_size(res));
139}
140EXPORT_SYMBOL_GPL(pci_ioremap_bar);
141
142void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar)
143{
144 /*
145 * Make sure the BAR is actually a memory resource, not an IO resource
146 */
147 if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
148 WARN_ON(1);
149 return NULL;
150 }
151 return ioremap_wc(pci_resource_start(pdev, bar),
152 pci_resource_len(pdev, bar));
153}
154EXPORT_SYMBOL_GPL(pci_ioremap_wc_bar);
155#endif
156
157
158static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
159 u8 pos, int cap, int *ttl)
160{
161 u8 id;
162 u16 ent;
163
164 pci_bus_read_config_byte(bus, devfn, pos, &pos);
165
166 while ((*ttl)--) {
167 if (pos < 0x40)
168 break;
169 pos &= ~3;
170 pci_bus_read_config_word(bus, devfn, pos, &ent);
171
172 id = ent & 0xff;
173 if (id == 0xff)
174 break;
175 if (id == cap)
176 return pos;
177 pos = (ent >> 8);
178 }
179 return 0;
180}
181
182static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
183 u8 pos, int cap)
184{
185 int ttl = PCI_FIND_CAP_TTL;
186
187 return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
188}
189
190int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
191{
192 return __pci_find_next_cap(dev->bus, dev->devfn,
193 pos + PCI_CAP_LIST_NEXT, cap);
194}
195EXPORT_SYMBOL_GPL(pci_find_next_capability);
196
197static int __pci_bus_find_cap_start(struct pci_bus *bus,
198 unsigned int devfn, u8 hdr_type)
199{
200 u16 status;
201
202 pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
203 if (!(status & PCI_STATUS_CAP_LIST))
204 return 0;
205
206 switch (hdr_type) {
207 case PCI_HEADER_TYPE_NORMAL:
208 case PCI_HEADER_TYPE_BRIDGE:
209 return PCI_CAPABILITY_LIST;
210 case PCI_HEADER_TYPE_CARDBUS:
211 return PCI_CB_CAPABILITY_LIST;
212 }
213
214 return 0;
215}
216
217/**
218 * pci_find_capability - query for devices' capabilities
219 * @dev: PCI device to query
220 * @cap: capability code
221 *
222 * Tell if a device supports a given PCI capability.
223 * Returns the address of the requested capability structure within the
224 * device's PCI configuration space or 0 in case the device does not
225 * support it. Possible values for @cap:
226 *
227 * %PCI_CAP_ID_PM Power Management
228 * %PCI_CAP_ID_AGP Accelerated Graphics Port
229 * %PCI_CAP_ID_VPD Vital Product Data
230 * %PCI_CAP_ID_SLOTID Slot Identification
231 * %PCI_CAP_ID_MSI Message Signalled Interrupts
232 * %PCI_CAP_ID_CHSWP CompactPCI HotSwap
233 * %PCI_CAP_ID_PCIX PCI-X
234 * %PCI_CAP_ID_EXP PCI Express
235 */
236int pci_find_capability(struct pci_dev *dev, int cap)
237{
238 int pos;
239
240 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
241 if (pos)
242 pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
243
244 return pos;
245}
246EXPORT_SYMBOL(pci_find_capability);
247
248/**
249 * pci_bus_find_capability - query for devices' capabilities
250 * @bus: the PCI bus to query
251 * @devfn: PCI device to query
252 * @cap: capability code
253 *
254 * Like pci_find_capability() but works for pci devices that do not have a
255 * pci_dev structure set up yet.
256 *
257 * Returns the address of the requested capability structure within the
258 * device's PCI configuration space or 0 in case the device does not
259 * support it.
260 */
261int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
262{
263 int pos;
264 u8 hdr_type;
265
266 pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
267
268 pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
269 if (pos)
270 pos = __pci_find_next_cap(bus, devfn, pos, cap);
271
272 return pos;
273}
274EXPORT_SYMBOL(pci_bus_find_capability);
275
276/**
277 * pci_find_next_ext_capability - Find an extended capability
278 * @dev: PCI device to query
279 * @start: address at which to start looking (0 to start at beginning of list)
280 * @cap: capability code
281 *
282 * Returns the address of the next matching extended capability structure
283 * within the device's PCI configuration space or 0 if the device does
284 * not support it. Some capabilities can occur several times, e.g., the
285 * vendor-specific capability, and this provides a way to find them all.
286 */
287int pci_find_next_ext_capability(struct pci_dev *dev, int start, int cap)
288{
289 u32 header;
290 int ttl;
291 int pos = PCI_CFG_SPACE_SIZE;
292
293 /* minimum 8 bytes per capability */
294 ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
295
296 if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
297 return 0;
298
299 if (start)
300 pos = start;
301
302 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
303 return 0;
304
305 /*
306 * If we have no capabilities, this is indicated by cap ID,
307 * cap version and next pointer all being 0.
308 */
309 if (header == 0)
310 return 0;
311
312 while (ttl-- > 0) {
313 if (PCI_EXT_CAP_ID(header) == cap && pos != start)
314 return pos;
315
316 pos = PCI_EXT_CAP_NEXT(header);
317 if (pos < PCI_CFG_SPACE_SIZE)
318 break;
319
320 if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
321 break;
322 }
323
324 return 0;
325}
326EXPORT_SYMBOL_GPL(pci_find_next_ext_capability);
327
328/**
329 * pci_find_ext_capability - Find an extended capability
330 * @dev: PCI device to query
331 * @cap: capability code
332 *
333 * Returns the address of the requested extended capability structure
334 * within the device's PCI configuration space or 0 if the device does
335 * not support it. Possible values for @cap:
336 *
337 * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
338 * %PCI_EXT_CAP_ID_VC Virtual Channel
339 * %PCI_EXT_CAP_ID_DSN Device Serial Number
340 * %PCI_EXT_CAP_ID_PWR Power Budgeting
341 */
342int pci_find_ext_capability(struct pci_dev *dev, int cap)
343{
344 return pci_find_next_ext_capability(dev, 0, cap);
345}
346EXPORT_SYMBOL_GPL(pci_find_ext_capability);
347
348static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
349{
350 int rc, ttl = PCI_FIND_CAP_TTL;
351 u8 cap, mask;
352
353 if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
354 mask = HT_3BIT_CAP_MASK;
355 else
356 mask = HT_5BIT_CAP_MASK;
357
358 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
359 PCI_CAP_ID_HT, &ttl);
360 while (pos) {
361 rc = pci_read_config_byte(dev, pos + 3, &cap);
362 if (rc != PCIBIOS_SUCCESSFUL)
363 return 0;
364
365 if ((cap & mask) == ht_cap)
366 return pos;
367
368 pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
369 pos + PCI_CAP_LIST_NEXT,
370 PCI_CAP_ID_HT, &ttl);
371 }
372
373 return 0;
374}
375/**
376 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
377 * @dev: PCI device to query
378 * @pos: Position from which to continue searching
379 * @ht_cap: Hypertransport capability code
380 *
381 * To be used in conjunction with pci_find_ht_capability() to search for
382 * all capabilities matching @ht_cap. @pos should always be a value returned
383 * from pci_find_ht_capability().
384 *
385 * NB. To be 100% safe against broken PCI devices, the caller should take
386 * steps to avoid an infinite loop.
387 */
388int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
389{
390 return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
391}
392EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
393
394/**
395 * pci_find_ht_capability - query a device's Hypertransport capabilities
396 * @dev: PCI device to query
397 * @ht_cap: Hypertransport capability code
398 *
399 * Tell if a device supports a given Hypertransport capability.
400 * Returns an address within the device's PCI configuration space
401 * or 0 in case the device does not support the request capability.
402 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
403 * which has a Hypertransport capability matching @ht_cap.
404 */
405int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
406{
407 int pos;
408
409 pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
410 if (pos)
411 pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
412
413 return pos;
414}
415EXPORT_SYMBOL_GPL(pci_find_ht_capability);
416
417/**
418 * pci_find_parent_resource - return resource region of parent bus of given region
419 * @dev: PCI device structure contains resources to be searched
420 * @res: child resource record for which parent is sought
421 *
422 * For given resource region of given device, return the resource
423 * region of parent bus the given region is contained in.
424 */
425struct resource *pci_find_parent_resource(const struct pci_dev *dev,
426 struct resource *res)
427{
428 const struct pci_bus *bus = dev->bus;
429 struct resource *r;
430 int i;
431
432 pci_bus_for_each_resource(bus, r, i) {
433 if (!r)
434 continue;
435 if (res->start && resource_contains(r, res)) {
436
437 /*
438 * If the window is prefetchable but the BAR is
439 * not, the allocator made a mistake.
440 */
441 if (r->flags & IORESOURCE_PREFETCH &&
442 !(res->flags & IORESOURCE_PREFETCH))
443 return NULL;
444
445 /*
446 * If we're below a transparent bridge, there may
447 * be both a positively-decoded aperture and a
448 * subtractively-decoded region that contain the BAR.
449 * We want the positively-decoded one, so this depends
450 * on pci_bus_for_each_resource() giving us those
451 * first.
452 */
453 return r;
454 }
455 }
456 return NULL;
457}
458EXPORT_SYMBOL(pci_find_parent_resource);
459
460/**
461 * pci_find_pcie_root_port - return PCIe Root Port
462 * @dev: PCI device to query
463 *
464 * Traverse up the parent chain and return the PCIe Root Port PCI Device
465 * for a given PCI Device.
466 */
467struct pci_dev *pci_find_pcie_root_port(struct pci_dev *dev)
468{
469 struct pci_dev *bridge, *highest_pcie_bridge = NULL;
470
471 bridge = pci_upstream_bridge(dev);
472 while (bridge && pci_is_pcie(bridge)) {
473 highest_pcie_bridge = bridge;
474 bridge = pci_upstream_bridge(bridge);
475 }
476
477 if (pci_pcie_type(highest_pcie_bridge) != PCI_EXP_TYPE_ROOT_PORT)
478 return NULL;
479
480 return highest_pcie_bridge;
481}
482EXPORT_SYMBOL(pci_find_pcie_root_port);
483
484/**
485 * pci_wait_for_pending - wait for @mask bit(s) to clear in status word @pos
486 * @dev: the PCI device to operate on
487 * @pos: config space offset of status word
488 * @mask: mask of bit(s) to care about in status word
489 *
490 * Return 1 when mask bit(s) in status word clear, 0 otherwise.
491 */
492int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask)
493{
494 int i;
495
496 /* Wait for Transaction Pending bit clean */
497 for (i = 0; i < 4; i++) {
498 u16 status;
499 if (i)
500 msleep((1 << (i - 1)) * 100);
501
502 pci_read_config_word(dev, pos, &status);
503 if (!(status & mask))
504 return 1;
505 }
506
507 return 0;
508}
509
510/**
511 * pci_restore_bars - restore a device's BAR values (e.g. after wake-up)
512 * @dev: PCI device to have its BARs restored
513 *
514 * Restore the BAR values for a given device, so as to make it
515 * accessible by its driver.
516 */
517static void pci_restore_bars(struct pci_dev *dev)
518{
519 int i;
520
521 /* Per SR-IOV spec 3.4.1.11, VF BARs are RO zero */
522 if (dev->is_virtfn)
523 return;
524
525 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
526 pci_update_resource(dev, i);
527}
528
529static const struct pci_platform_pm_ops *pci_platform_pm;
530
531int pci_set_platform_pm(const struct pci_platform_pm_ops *ops)
532{
533 if (!ops->is_manageable || !ops->set_state || !ops->choose_state
534 || !ops->sleep_wake)
535 return -EINVAL;
536 pci_platform_pm = ops;
537 return 0;
538}
539
540static inline bool platform_pci_power_manageable(struct pci_dev *dev)
541{
542 return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
543}
544
545static inline int platform_pci_set_power_state(struct pci_dev *dev,
546 pci_power_t t)
547{
548 return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
549}
550
551static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
552{
553 return pci_platform_pm ?
554 pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
555}
556
557static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
558{
559 return pci_platform_pm ?
560 pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
561}
562
563static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable)
564{
565 return pci_platform_pm ?
566 pci_platform_pm->run_wake(dev, enable) : -ENODEV;
567}
568
569static inline bool platform_pci_need_resume(struct pci_dev *dev)
570{
571 return pci_platform_pm ? pci_platform_pm->need_resume(dev) : false;
572}
573
574/**
575 * pci_raw_set_power_state - Use PCI PM registers to set the power state of
576 * given PCI device
577 * @dev: PCI device to handle.
578 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
579 *
580 * RETURN VALUE:
581 * -EINVAL if the requested state is invalid.
582 * -EIO if device does not support PCI PM or its PM capabilities register has a
583 * wrong version, or device doesn't support the requested state.
584 * 0 if device already is in the requested state.
585 * 0 if device's power state has been successfully changed.
586 */
587static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
588{
589 u16 pmcsr;
590 bool need_restore = false;
591
592 /* Check if we're already there */
593 if (dev->current_state == state)
594 return 0;
595
596 if (!dev->pm_cap)
597 return -EIO;
598
599 if (state < PCI_D0 || state > PCI_D3hot)
600 return -EINVAL;
601
602 /* Validate current state:
603 * Can enter D0 from any state, but if we can only go deeper
604 * to sleep if we're already in a low power state
605 */
606 if (state != PCI_D0 && dev->current_state <= PCI_D3cold
607 && dev->current_state > state) {
608 dev_err(&dev->dev, "invalid power transition (from state %d to %d)\n",
609 dev->current_state, state);
610 return -EINVAL;
611 }
612
613 /* check if this device supports the desired state */
614 if ((state == PCI_D1 && !dev->d1_support)
615 || (state == PCI_D2 && !dev->d2_support))
616 return -EIO;
617
618 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
619
620 /* If we're (effectively) in D3, force entire word to 0.
621 * This doesn't affect PME_Status, disables PME_En, and
622 * sets PowerState to 0.
623 */
624 switch (dev->current_state) {
625 case PCI_D0:
626 case PCI_D1:
627 case PCI_D2:
628 pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
629 pmcsr |= state;
630 break;
631 case PCI_D3hot:
632 case PCI_D3cold:
633 case PCI_UNKNOWN: /* Boot-up */
634 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
635 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
636 need_restore = true;
637 /* Fall-through: force to D0 */
638 default:
639 pmcsr = 0;
640 break;
641 }
642
643 /* enter specified state */
644 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
645
646 /* Mandatory power management transition delays */
647 /* see PCI PM 1.1 5.6.1 table 18 */
648 if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
649 pci_dev_d3_sleep(dev);
650 else if (state == PCI_D2 || dev->current_state == PCI_D2)
651 udelay(PCI_PM_D2_DELAY);
652
653 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
654 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
655 if (dev->current_state != state && printk_ratelimit())
656 dev_info(&dev->dev, "Refused to change power state, currently in D%d\n",
657 dev->current_state);
658
659 /*
660 * According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
661 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
662 * from D3hot to D0 _may_ perform an internal reset, thereby
663 * going to "D0 Uninitialized" rather than "D0 Initialized".
664 * For example, at least some versions of the 3c905B and the
665 * 3c556B exhibit this behaviour.
666 *
667 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
668 * devices in a D3hot state at boot. Consequently, we need to
669 * restore at least the BARs so that the device will be
670 * accessible to its driver.
671 */
672 if (need_restore)
673 pci_restore_bars(dev);
674
675 if (dev->bus->self)
676 pcie_aspm_pm_state_change(dev->bus->self);
677
678 return 0;
679}
680
681/**
682 * pci_update_current_state - Read PCI power state of given device from its
683 * PCI PM registers and cache it
684 * @dev: PCI device to handle.
685 * @state: State to cache in case the device doesn't have the PM capability
686 */
687void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
688{
689 if (dev->pm_cap) {
690 u16 pmcsr;
691
692 /*
693 * Configuration space is not accessible for device in
694 * D3cold, so just keep or set D3cold for safety
695 */
696 if (dev->current_state == PCI_D3cold)
697 return;
698 if (state == PCI_D3cold) {
699 dev->current_state = PCI_D3cold;
700 return;
701 }
702 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
703 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
704 } else {
705 dev->current_state = state;
706 }
707}
708
709/**
710 * pci_power_up - Put the given device into D0 forcibly
711 * @dev: PCI device to power up
712 */
713void pci_power_up(struct pci_dev *dev)
714{
715 if (platform_pci_power_manageable(dev))
716 platform_pci_set_power_state(dev, PCI_D0);
717
718 pci_raw_set_power_state(dev, PCI_D0);
719 pci_update_current_state(dev, PCI_D0);
720}
721
722/**
723 * pci_platform_power_transition - Use platform to change device power state
724 * @dev: PCI device to handle.
725 * @state: State to put the device into.
726 */
727static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
728{
729 int error;
730
731 if (platform_pci_power_manageable(dev)) {
732 error = platform_pci_set_power_state(dev, state);
733 if (!error)
734 pci_update_current_state(dev, state);
735 } else
736 error = -ENODEV;
737
738 if (error && !dev->pm_cap) /* Fall back to PCI_D0 */
739 dev->current_state = PCI_D0;
740
741 return error;
742}
743
744/**
745 * pci_wakeup - Wake up a PCI device
746 * @pci_dev: Device to handle.
747 * @ign: ignored parameter
748 */
749static int pci_wakeup(struct pci_dev *pci_dev, void *ign)
750{
751 pci_wakeup_event(pci_dev);
752 pm_request_resume(&pci_dev->dev);
753 return 0;
754}
755
756/**
757 * pci_wakeup_bus - Walk given bus and wake up devices on it
758 * @bus: Top bus of the subtree to walk.
759 */
760static void pci_wakeup_bus(struct pci_bus *bus)
761{
762 if (bus)
763 pci_walk_bus(bus, pci_wakeup, NULL);
764}
765
766/**
767 * __pci_start_power_transition - Start power transition of a PCI device
768 * @dev: PCI device to handle.
769 * @state: State to put the device into.
770 */
771static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
772{
773 if (state == PCI_D0) {
774 pci_platform_power_transition(dev, PCI_D0);
775 /*
776 * Mandatory power management transition delays, see
777 * PCI Express Base Specification Revision 2.0 Section
778 * 6.6.1: Conventional Reset. Do not delay for
779 * devices powered on/off by corresponding bridge,
780 * because have already delayed for the bridge.
781 */
782 if (dev->runtime_d3cold) {
783 msleep(dev->d3cold_delay);
784 /*
785 * When powering on a bridge from D3cold, the
786 * whole hierarchy may be powered on into
787 * D0uninitialized state, resume them to give
788 * them a chance to suspend again
789 */
790 pci_wakeup_bus(dev->subordinate);
791 }
792 }
793}
794
795/**
796 * __pci_dev_set_current_state - Set current state of a PCI device
797 * @dev: Device to handle
798 * @data: pointer to state to be set
799 */
800static int __pci_dev_set_current_state(struct pci_dev *dev, void *data)
801{
802 pci_power_t state = *(pci_power_t *)data;
803
804 dev->current_state = state;
805 return 0;
806}
807
808/**
809 * __pci_bus_set_current_state - Walk given bus and set current state of devices
810 * @bus: Top bus of the subtree to walk.
811 * @state: state to be set
812 */
813static void __pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
814{
815 if (bus)
816 pci_walk_bus(bus, __pci_dev_set_current_state, &state);
817}
818
819/**
820 * __pci_complete_power_transition - Complete power transition of a PCI device
821 * @dev: PCI device to handle.
822 * @state: State to put the device into.
823 *
824 * This function should not be called directly by device drivers.
825 */
826int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
827{
828 int ret;
829
830 if (state <= PCI_D0)
831 return -EINVAL;
832 ret = pci_platform_power_transition(dev, state);
833 /* Power off the bridge may power off the whole hierarchy */
834 if (!ret && state == PCI_D3cold)
835 __pci_bus_set_current_state(dev->subordinate, PCI_D3cold);
836 return ret;
837}
838EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
839
840/**
841 * pci_set_power_state - Set the power state of a PCI device
842 * @dev: PCI device to handle.
843 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
844 *
845 * Transition a device to a new power state, using the platform firmware and/or
846 * the device's PCI PM registers.
847 *
848 * RETURN VALUE:
849 * -EINVAL if the requested state is invalid.
850 * -EIO if device does not support PCI PM or its PM capabilities register has a
851 * wrong version, or device doesn't support the requested state.
852 * 0 if device already is in the requested state.
853 * 0 if device's power state has been successfully changed.
854 */
855int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
856{
857 int error;
858
859 /* bound the state we're entering */
860 if (state > PCI_D3cold)
861 state = PCI_D3cold;
862 else if (state < PCI_D0)
863 state = PCI_D0;
864 else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
865 /*
866 * If the device or the parent bridge do not support PCI PM,
867 * ignore the request if we're doing anything other than putting
868 * it into D0 (which would only happen on boot).
869 */
870 return 0;
871
872 /* Check if we're already there */
873 if (dev->current_state == state)
874 return 0;
875
876 __pci_start_power_transition(dev, state);
877
878 /* This device is quirked not to be put into D3, so
879 don't put it in D3 */
880 if (state >= PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
881 return 0;
882
883 /*
884 * To put device in D3cold, we put device into D3hot in native
885 * way, then put device into D3cold with platform ops
886 */
887 error = pci_raw_set_power_state(dev, state > PCI_D3hot ?
888 PCI_D3hot : state);
889
890 if (!__pci_complete_power_transition(dev, state))
891 error = 0;
892
893 return error;
894}
895EXPORT_SYMBOL(pci_set_power_state);
896
897/**
898 * pci_choose_state - Choose the power state of a PCI device
899 * @dev: PCI device to be suspended
900 * @state: target sleep state for the whole system. This is the value
901 * that is passed to suspend() function.
902 *
903 * Returns PCI power state suitable for given device and given system
904 * message.
905 */
906
907pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
908{
909 pci_power_t ret;
910
911 if (!dev->pm_cap)
912 return PCI_D0;
913
914 ret = platform_pci_choose_state(dev);
915 if (ret != PCI_POWER_ERROR)
916 return ret;
917
918 switch (state.event) {
919 case PM_EVENT_ON:
920 return PCI_D0;
921 case PM_EVENT_FREEZE:
922 case PM_EVENT_PRETHAW:
923 /* REVISIT both freeze and pre-thaw "should" use D0 */
924 case PM_EVENT_SUSPEND:
925 case PM_EVENT_HIBERNATE:
926 return PCI_D3hot;
927 default:
928 dev_info(&dev->dev, "unrecognized suspend event %d\n",
929 state.event);
930 BUG();
931 }
932 return PCI_D0;
933}
934EXPORT_SYMBOL(pci_choose_state);
935
936#define PCI_EXP_SAVE_REGS 7
937
938static struct pci_cap_saved_state *_pci_find_saved_cap(struct pci_dev *pci_dev,
939 u16 cap, bool extended)
940{
941 struct pci_cap_saved_state *tmp;
942
943 hlist_for_each_entry(tmp, &pci_dev->saved_cap_space, next) {
944 if (tmp->cap.cap_extended == extended && tmp->cap.cap_nr == cap)
945 return tmp;
946 }
947 return NULL;
948}
949
950struct pci_cap_saved_state *pci_find_saved_cap(struct pci_dev *dev, char cap)
951{
952 return _pci_find_saved_cap(dev, cap, false);
953}
954
955struct pci_cap_saved_state *pci_find_saved_ext_cap(struct pci_dev *dev, u16 cap)
956{
957 return _pci_find_saved_cap(dev, cap, true);
958}
959
960static int pci_save_pcie_state(struct pci_dev *dev)
961{
962 int i = 0;
963 struct pci_cap_saved_state *save_state;
964 u16 *cap;
965
966 if (!pci_is_pcie(dev))
967 return 0;
968
969 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
970 if (!save_state) {
971 dev_err(&dev->dev, "buffer not found in %s\n", __func__);
972 return -ENOMEM;
973 }
974
975 cap = (u16 *)&save_state->cap.data[0];
976 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &cap[i++]);
977 pcie_capability_read_word(dev, PCI_EXP_LNKCTL, &cap[i++]);
978 pcie_capability_read_word(dev, PCI_EXP_SLTCTL, &cap[i++]);
979 pcie_capability_read_word(dev, PCI_EXP_RTCTL, &cap[i++]);
980 pcie_capability_read_word(dev, PCI_EXP_DEVCTL2, &cap[i++]);
981 pcie_capability_read_word(dev, PCI_EXP_LNKCTL2, &cap[i++]);
982 pcie_capability_read_word(dev, PCI_EXP_SLTCTL2, &cap[i++]);
983
984 return 0;
985}
986
987static void pci_restore_pcie_state(struct pci_dev *dev)
988{
989 int i = 0;
990 struct pci_cap_saved_state *save_state;
991 u16 *cap;
992
993 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
994 if (!save_state)
995 return;
996
997 cap = (u16 *)&save_state->cap.data[0];
998 pcie_capability_write_word(dev, PCI_EXP_DEVCTL, cap[i++]);
999 pcie_capability_write_word(dev, PCI_EXP_LNKCTL, cap[i++]);
1000 pcie_capability_write_word(dev, PCI_EXP_SLTCTL, cap[i++]);
1001 pcie_capability_write_word(dev, PCI_EXP_RTCTL, cap[i++]);
1002 pcie_capability_write_word(dev, PCI_EXP_DEVCTL2, cap[i++]);
1003 pcie_capability_write_word(dev, PCI_EXP_LNKCTL2, cap[i++]);
1004 pcie_capability_write_word(dev, PCI_EXP_SLTCTL2, cap[i++]);
1005}
1006
1007
1008static int pci_save_pcix_state(struct pci_dev *dev)
1009{
1010 int pos;
1011 struct pci_cap_saved_state *save_state;
1012
1013 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1014 if (!pos)
1015 return 0;
1016
1017 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
1018 if (!save_state) {
1019 dev_err(&dev->dev, "buffer not found in %s\n", __func__);
1020 return -ENOMEM;
1021 }
1022
1023 pci_read_config_word(dev, pos + PCI_X_CMD,
1024 (u16 *)save_state->cap.data);
1025
1026 return 0;
1027}
1028
1029static void pci_restore_pcix_state(struct pci_dev *dev)
1030{
1031 int i = 0, pos;
1032 struct pci_cap_saved_state *save_state;
1033 u16 *cap;
1034
1035 save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
1036 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1037 if (!save_state || !pos)
1038 return;
1039 cap = (u16 *)&save_state->cap.data[0];
1040
1041 pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
1042}
1043
1044
1045/**
1046 * pci_save_state - save the PCI configuration space of a device before suspending
1047 * @dev: - PCI device that we're dealing with
1048 */
1049int pci_save_state(struct pci_dev *dev)
1050{
1051 int i;
1052 /* XXX: 100% dword access ok here? */
1053 for (i = 0; i < 16; i++)
1054 pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
1055 dev->state_saved = true;
1056
1057 i = pci_save_pcie_state(dev);
1058 if (i != 0)
1059 return i;
1060
1061 i = pci_save_pcix_state(dev);
1062 if (i != 0)
1063 return i;
1064
1065 return pci_save_vc_state(dev);
1066}
1067EXPORT_SYMBOL(pci_save_state);
1068
1069static void pci_restore_config_dword(struct pci_dev *pdev, int offset,
1070 u32 saved_val, int retry)
1071{
1072 u32 val;
1073
1074 pci_read_config_dword(pdev, offset, &val);
1075 if (val == saved_val)
1076 return;
1077
1078 for (;;) {
1079 dev_dbg(&pdev->dev, "restoring config space at offset %#x (was %#x, writing %#x)\n",
1080 offset, val, saved_val);
1081 pci_write_config_dword(pdev, offset, saved_val);
1082 if (retry-- <= 0)
1083 return;
1084
1085 pci_read_config_dword(pdev, offset, &val);
1086 if (val == saved_val)
1087 return;
1088
1089 mdelay(1);
1090 }
1091}
1092
1093static void pci_restore_config_space_range(struct pci_dev *pdev,
1094 int start, int end, int retry)
1095{
1096 int index;
1097
1098 for (index = end; index >= start; index--)
1099 pci_restore_config_dword(pdev, 4 * index,
1100 pdev->saved_config_space[index],
1101 retry);
1102}
1103
1104static void pci_restore_config_space(struct pci_dev *pdev)
1105{
1106 if (pdev->hdr_type == PCI_HEADER_TYPE_NORMAL) {
1107 pci_restore_config_space_range(pdev, 10, 15, 0);
1108 /* Restore BARs before the command register. */
1109 pci_restore_config_space_range(pdev, 4, 9, 10);
1110 pci_restore_config_space_range(pdev, 0, 3, 0);
1111 } else {
1112 pci_restore_config_space_range(pdev, 0, 15, 0);
1113 }
1114}
1115
1116/**
1117 * pci_restore_state - Restore the saved state of a PCI device
1118 * @dev: - PCI device that we're dealing with
1119 */
1120void pci_restore_state(struct pci_dev *dev)
1121{
1122 if (!dev->state_saved)
1123 return;
1124
1125 /* PCI Express register must be restored first */
1126 pci_restore_pcie_state(dev);
1127 pci_restore_ats_state(dev);
1128 pci_restore_vc_state(dev);
1129
1130 pci_cleanup_aer_error_status_regs(dev);
1131
1132 pci_restore_config_space(dev);
1133
1134 pci_restore_pcix_state(dev);
1135 pci_restore_msi_state(dev);
1136
1137 /* Restore ACS and IOV configuration state */
1138 pci_enable_acs(dev);
1139 pci_restore_iov_state(dev);
1140
1141 dev->state_saved = false;
1142}
1143EXPORT_SYMBOL(pci_restore_state);
1144
1145struct pci_saved_state {
1146 u32 config_space[16];
1147 struct pci_cap_saved_data cap[0];
1148};
1149
1150/**
1151 * pci_store_saved_state - Allocate and return an opaque struct containing
1152 * the device saved state.
1153 * @dev: PCI device that we're dealing with
1154 *
1155 * Return NULL if no state or error.
1156 */
1157struct pci_saved_state *pci_store_saved_state(struct pci_dev *dev)
1158{
1159 struct pci_saved_state *state;
1160 struct pci_cap_saved_state *tmp;
1161 struct pci_cap_saved_data *cap;
1162 size_t size;
1163
1164 if (!dev->state_saved)
1165 return NULL;
1166
1167 size = sizeof(*state) + sizeof(struct pci_cap_saved_data);
1168
1169 hlist_for_each_entry(tmp, &dev->saved_cap_space, next)
1170 size += sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1171
1172 state = kzalloc(size, GFP_KERNEL);
1173 if (!state)
1174 return NULL;
1175
1176 memcpy(state->config_space, dev->saved_config_space,
1177 sizeof(state->config_space));
1178
1179 cap = state->cap;
1180 hlist_for_each_entry(tmp, &dev->saved_cap_space, next) {
1181 size_t len = sizeof(struct pci_cap_saved_data) + tmp->cap.size;
1182 memcpy(cap, &tmp->cap, len);
1183 cap = (struct pci_cap_saved_data *)((u8 *)cap + len);
1184 }
1185 /* Empty cap_save terminates list */
1186
1187 return state;
1188}
1189EXPORT_SYMBOL_GPL(pci_store_saved_state);
1190
1191/**
1192 * pci_load_saved_state - Reload the provided save state into struct pci_dev.
1193 * @dev: PCI device that we're dealing with
1194 * @state: Saved state returned from pci_store_saved_state()
1195 */
1196int pci_load_saved_state(struct pci_dev *dev,
1197 struct pci_saved_state *state)
1198{
1199 struct pci_cap_saved_data *cap;
1200
1201 dev->state_saved = false;
1202
1203 if (!state)
1204 return 0;
1205
1206 memcpy(dev->saved_config_space, state->config_space,
1207 sizeof(state->config_space));
1208
1209 cap = state->cap;
1210 while (cap->size) {
1211 struct pci_cap_saved_state *tmp;
1212
1213 tmp = _pci_find_saved_cap(dev, cap->cap_nr, cap->cap_extended);
1214 if (!tmp || tmp->cap.size != cap->size)
1215 return -EINVAL;
1216
1217 memcpy(tmp->cap.data, cap->data, tmp->cap.size);
1218 cap = (struct pci_cap_saved_data *)((u8 *)cap +
1219 sizeof(struct pci_cap_saved_data) + cap->size);
1220 }
1221
1222 dev->state_saved = true;
1223 return 0;
1224}
1225EXPORT_SYMBOL_GPL(pci_load_saved_state);
1226
1227/**
1228 * pci_load_and_free_saved_state - Reload the save state pointed to by state,
1229 * and free the memory allocated for it.
1230 * @dev: PCI device that we're dealing with
1231 * @state: Pointer to saved state returned from pci_store_saved_state()
1232 */
1233int pci_load_and_free_saved_state(struct pci_dev *dev,
1234 struct pci_saved_state **state)
1235{
1236 int ret = pci_load_saved_state(dev, *state);
1237 kfree(*state);
1238 *state = NULL;
1239 return ret;
1240}
1241EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state);
1242
1243int __weak pcibios_enable_device(struct pci_dev *dev, int bars)
1244{
1245 return pci_enable_resources(dev, bars);
1246}
1247
1248static int do_pci_enable_device(struct pci_dev *dev, int bars)
1249{
1250 int err;
1251 struct pci_dev *bridge;
1252 u16 cmd;
1253 u8 pin;
1254
1255 err = pci_set_power_state(dev, PCI_D0);
1256 if (err < 0 && err != -EIO)
1257 return err;
1258
1259 bridge = pci_upstream_bridge(dev);
1260 if (bridge)
1261 pcie_aspm_powersave_config_link(bridge);
1262
1263 err = pcibios_enable_device(dev, bars);
1264 if (err < 0)
1265 return err;
1266 pci_fixup_device(pci_fixup_enable, dev);
1267
1268 if (dev->msi_enabled || dev->msix_enabled)
1269 return 0;
1270
1271 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1272 if (pin) {
1273 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1274 if (cmd & PCI_COMMAND_INTX_DISABLE)
1275 pci_write_config_word(dev, PCI_COMMAND,
1276 cmd & ~PCI_COMMAND_INTX_DISABLE);
1277 }
1278
1279 return 0;
1280}
1281
1282/**
1283 * pci_reenable_device - Resume abandoned device
1284 * @dev: PCI device to be resumed
1285 *
1286 * Note this function is a backend of pci_default_resume and is not supposed
1287 * to be called by normal code, write proper resume handler and use it instead.
1288 */
1289int pci_reenable_device(struct pci_dev *dev)
1290{
1291 if (pci_is_enabled(dev))
1292 return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
1293 return 0;
1294}
1295EXPORT_SYMBOL(pci_reenable_device);
1296
1297static void pci_enable_bridge(struct pci_dev *dev)
1298{
1299 struct pci_dev *bridge;
1300 int retval;
1301
1302 bridge = pci_upstream_bridge(dev);
1303 if (bridge)
1304 pci_enable_bridge(bridge);
1305
1306 if (pci_is_enabled(dev)) {
1307 if (!dev->is_busmaster)
1308 pci_set_master(dev);
1309 return;
1310 }
1311
1312 retval = pci_enable_device(dev);
1313 if (retval)
1314 dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n",
1315 retval);
1316 pci_set_master(dev);
1317}
1318
1319static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags)
1320{
1321 struct pci_dev *bridge;
1322 int err;
1323 int i, bars = 0;
1324
1325 /*
1326 * Power state could be unknown at this point, either due to a fresh
1327 * boot or a device removal call. So get the current power state
1328 * so that things like MSI message writing will behave as expected
1329 * (e.g. if the device really is in D0 at enable time).
1330 */
1331 if (dev->pm_cap) {
1332 u16 pmcsr;
1333 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1334 dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
1335 }
1336
1337 if (atomic_inc_return(&dev->enable_cnt) > 1)
1338 return 0; /* already enabled */
1339
1340 bridge = pci_upstream_bridge(dev);
1341 if (bridge)
1342 pci_enable_bridge(bridge);
1343
1344 /* only skip sriov related */
1345 for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1346 if (dev->resource[i].flags & flags)
1347 bars |= (1 << i);
1348 for (i = PCI_BRIDGE_RESOURCES; i < DEVICE_COUNT_RESOURCE; i++)
1349 if (dev->resource[i].flags & flags)
1350 bars |= (1 << i);
1351
1352 err = do_pci_enable_device(dev, bars);
1353 if (err < 0)
1354 atomic_dec(&dev->enable_cnt);
1355 return err;
1356}
1357
1358/**
1359 * pci_enable_device_io - Initialize a device for use with IO space
1360 * @dev: PCI device to be initialized
1361 *
1362 * Initialize device before it's used by a driver. Ask low-level code
1363 * to enable I/O resources. Wake up the device if it was suspended.
1364 * Beware, this function can fail.
1365 */
1366int pci_enable_device_io(struct pci_dev *dev)
1367{
1368 return pci_enable_device_flags(dev, IORESOURCE_IO);
1369}
1370EXPORT_SYMBOL(pci_enable_device_io);
1371
1372/**
1373 * pci_enable_device_mem - Initialize a device for use with Memory space
1374 * @dev: PCI device to be initialized
1375 *
1376 * Initialize device before it's used by a driver. Ask low-level code
1377 * to enable Memory resources. Wake up the device if it was suspended.
1378 * Beware, this function can fail.
1379 */
1380int pci_enable_device_mem(struct pci_dev *dev)
1381{
1382 return pci_enable_device_flags(dev, IORESOURCE_MEM);
1383}
1384EXPORT_SYMBOL(pci_enable_device_mem);
1385
1386/**
1387 * pci_enable_device - Initialize device before it's used by a driver.
1388 * @dev: PCI device to be initialized
1389 *
1390 * Initialize device before it's used by a driver. Ask low-level code
1391 * to enable I/O and memory. Wake up the device if it was suspended.
1392 * Beware, this function can fail.
1393 *
1394 * Note we don't actually enable the device many times if we call
1395 * this function repeatedly (we just increment the count).
1396 */
1397int pci_enable_device(struct pci_dev *dev)
1398{
1399 return pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
1400}
1401EXPORT_SYMBOL(pci_enable_device);
1402
1403/*
1404 * Managed PCI resources. This manages device on/off, intx/msi/msix
1405 * on/off and BAR regions. pci_dev itself records msi/msix status, so
1406 * there's no need to track it separately. pci_devres is initialized
1407 * when a device is enabled using managed PCI device enable interface.
1408 */
1409struct pci_devres {
1410 unsigned int enabled:1;
1411 unsigned int pinned:1;
1412 unsigned int orig_intx:1;
1413 unsigned int restore_intx:1;
1414 u32 region_mask;
1415};
1416
1417static void pcim_release(struct device *gendev, void *res)
1418{
1419 struct pci_dev *dev = to_pci_dev(gendev);
1420 struct pci_devres *this = res;
1421 int i;
1422
1423 if (dev->msi_enabled)
1424 pci_disable_msi(dev);
1425 if (dev->msix_enabled)
1426 pci_disable_msix(dev);
1427
1428 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1429 if (this->region_mask & (1 << i))
1430 pci_release_region(dev, i);
1431
1432 if (this->restore_intx)
1433 pci_intx(dev, this->orig_intx);
1434
1435 if (this->enabled && !this->pinned)
1436 pci_disable_device(dev);
1437}
1438
1439static struct pci_devres *get_pci_dr(struct pci_dev *pdev)
1440{
1441 struct pci_devres *dr, *new_dr;
1442
1443 dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1444 if (dr)
1445 return dr;
1446
1447 new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1448 if (!new_dr)
1449 return NULL;
1450 return devres_get(&pdev->dev, new_dr, NULL, NULL);
1451}
1452
1453static struct pci_devres *find_pci_dr(struct pci_dev *pdev)
1454{
1455 if (pci_is_managed(pdev))
1456 return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1457 return NULL;
1458}
1459
1460/**
1461 * pcim_enable_device - Managed pci_enable_device()
1462 * @pdev: PCI device to be initialized
1463 *
1464 * Managed pci_enable_device().
1465 */
1466int pcim_enable_device(struct pci_dev *pdev)
1467{
1468 struct pci_devres *dr;
1469 int rc;
1470
1471 dr = get_pci_dr(pdev);
1472 if (unlikely(!dr))
1473 return -ENOMEM;
1474 if (dr->enabled)
1475 return 0;
1476
1477 rc = pci_enable_device(pdev);
1478 if (!rc) {
1479 pdev->is_managed = 1;
1480 dr->enabled = 1;
1481 }
1482 return rc;
1483}
1484EXPORT_SYMBOL(pcim_enable_device);
1485
1486/**
1487 * pcim_pin_device - Pin managed PCI device
1488 * @pdev: PCI device to pin
1489 *
1490 * Pin managed PCI device @pdev. Pinned device won't be disabled on
1491 * driver detach. @pdev must have been enabled with
1492 * pcim_enable_device().
1493 */
1494void pcim_pin_device(struct pci_dev *pdev)
1495{
1496 struct pci_devres *dr;
1497
1498 dr = find_pci_dr(pdev);
1499 WARN_ON(!dr || !dr->enabled);
1500 if (dr)
1501 dr->pinned = 1;
1502}
1503EXPORT_SYMBOL(pcim_pin_device);
1504
1505/*
1506 * pcibios_add_device - provide arch specific hooks when adding device dev
1507 * @dev: the PCI device being added
1508 *
1509 * Permits the platform to provide architecture specific functionality when
1510 * devices are added. This is the default implementation. Architecture
1511 * implementations can override this.
1512 */
1513int __weak pcibios_add_device(struct pci_dev *dev)
1514{
1515 return 0;
1516}
1517
1518/**
1519 * pcibios_release_device - provide arch specific hooks when releasing device dev
1520 * @dev: the PCI device being released
1521 *
1522 * Permits the platform to provide architecture specific functionality when
1523 * devices are released. This is the default implementation. Architecture
1524 * implementations can override this.
1525 */
1526void __weak pcibios_release_device(struct pci_dev *dev) {}
1527
1528/**
1529 * pcibios_disable_device - disable arch specific PCI resources for device dev
1530 * @dev: the PCI device to disable
1531 *
1532 * Disables architecture specific PCI resources for the device. This
1533 * is the default implementation. Architecture implementations can
1534 * override this.
1535 */
1536void __weak pcibios_disable_device(struct pci_dev *dev) {}
1537
1538/**
1539 * pcibios_penalize_isa_irq - penalize an ISA IRQ
1540 * @irq: ISA IRQ to penalize
1541 * @active: IRQ active or not
1542 *
1543 * Permits the platform to provide architecture-specific functionality when
1544 * penalizing ISA IRQs. This is the default implementation. Architecture
1545 * implementations can override this.
1546 */
1547void __weak pcibios_penalize_isa_irq(int irq, int active) {}
1548
1549static void do_pci_disable_device(struct pci_dev *dev)
1550{
1551 u16 pci_command;
1552
1553 pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1554 if (pci_command & PCI_COMMAND_MASTER) {
1555 pci_command &= ~PCI_COMMAND_MASTER;
1556 pci_write_config_word(dev, PCI_COMMAND, pci_command);
1557 }
1558
1559 pcibios_disable_device(dev);
1560}
1561
1562/**
1563 * pci_disable_enabled_device - Disable device without updating enable_cnt
1564 * @dev: PCI device to disable
1565 *
1566 * NOTE: This function is a backend of PCI power management routines and is
1567 * not supposed to be called drivers.
1568 */
1569void pci_disable_enabled_device(struct pci_dev *dev)
1570{
1571 if (pci_is_enabled(dev))
1572 do_pci_disable_device(dev);
1573}
1574
1575/**
1576 * pci_disable_device - Disable PCI device after use
1577 * @dev: PCI device to be disabled
1578 *
1579 * Signal to the system that the PCI device is not in use by the system
1580 * anymore. This only involves disabling PCI bus-mastering, if active.
1581 *
1582 * Note we don't actually disable the device until all callers of
1583 * pci_enable_device() have called pci_disable_device().
1584 */
1585void pci_disable_device(struct pci_dev *dev)
1586{
1587 struct pci_devres *dr;
1588
1589 dr = find_pci_dr(dev);
1590 if (dr)
1591 dr->enabled = 0;
1592
1593 dev_WARN_ONCE(&dev->dev, atomic_read(&dev->enable_cnt) <= 0,
1594 "disabling already-disabled device");
1595
1596 if (atomic_dec_return(&dev->enable_cnt) != 0)
1597 return;
1598
1599 do_pci_disable_device(dev);
1600
1601 dev->is_busmaster = 0;
1602}
1603EXPORT_SYMBOL(pci_disable_device);
1604
1605/**
1606 * pcibios_set_pcie_reset_state - set reset state for device dev
1607 * @dev: the PCIe device reset
1608 * @state: Reset state to enter into
1609 *
1610 *
1611 * Sets the PCIe reset state for the device. This is the default
1612 * implementation. Architecture implementations can override this.
1613 */
1614int __weak pcibios_set_pcie_reset_state(struct pci_dev *dev,
1615 enum pcie_reset_state state)
1616{
1617 return -EINVAL;
1618}
1619
1620/**
1621 * pci_set_pcie_reset_state - set reset state for device dev
1622 * @dev: the PCIe device reset
1623 * @state: Reset state to enter into
1624 *
1625 *
1626 * Sets the PCI reset state for the device.
1627 */
1628int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1629{
1630 return pcibios_set_pcie_reset_state(dev, state);
1631}
1632EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
1633
1634/**
1635 * pci_check_pme_status - Check if given device has generated PME.
1636 * @dev: Device to check.
1637 *
1638 * Check the PME status of the device and if set, clear it and clear PME enable
1639 * (if set). Return 'true' if PME status and PME enable were both set or
1640 * 'false' otherwise.
1641 */
1642bool pci_check_pme_status(struct pci_dev *dev)
1643{
1644 int pmcsr_pos;
1645 u16 pmcsr;
1646 bool ret = false;
1647
1648 if (!dev->pm_cap)
1649 return false;
1650
1651 pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
1652 pci_read_config_word(dev, pmcsr_pos, &pmcsr);
1653 if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
1654 return false;
1655
1656 /* Clear PME status. */
1657 pmcsr |= PCI_PM_CTRL_PME_STATUS;
1658 if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
1659 /* Disable PME to avoid interrupt flood. */
1660 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1661 ret = true;
1662 }
1663
1664 pci_write_config_word(dev, pmcsr_pos, pmcsr);
1665
1666 return ret;
1667}
1668
1669/**
1670 * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
1671 * @dev: Device to handle.
1672 * @pme_poll_reset: Whether or not to reset the device's pme_poll flag.
1673 *
1674 * Check if @dev has generated PME and queue a resume request for it in that
1675 * case.
1676 */
1677static int pci_pme_wakeup(struct pci_dev *dev, void *pme_poll_reset)
1678{
1679 if (pme_poll_reset && dev->pme_poll)
1680 dev->pme_poll = false;
1681
1682 if (pci_check_pme_status(dev)) {
1683 pci_wakeup_event(dev);
1684 pm_request_resume(&dev->dev);
1685 }
1686 return 0;
1687}
1688
1689/**
1690 * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
1691 * @bus: Top bus of the subtree to walk.
1692 */
1693void pci_pme_wakeup_bus(struct pci_bus *bus)
1694{
1695 if (bus)
1696 pci_walk_bus(bus, pci_pme_wakeup, (void *)true);
1697}
1698
1699
1700/**
1701 * pci_pme_capable - check the capability of PCI device to generate PME#
1702 * @dev: PCI device to handle.
1703 * @state: PCI state from which device will issue PME#.
1704 */
1705bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1706{
1707 if (!dev->pm_cap)
1708 return false;
1709
1710 return !!(dev->pme_support & (1 << state));
1711}
1712EXPORT_SYMBOL(pci_pme_capable);
1713
1714static void pci_pme_list_scan(struct work_struct *work)
1715{
1716 struct pci_pme_device *pme_dev, *n;
1717
1718 mutex_lock(&pci_pme_list_mutex);
1719 list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) {
1720 if (pme_dev->dev->pme_poll) {
1721 struct pci_dev *bridge;
1722
1723 bridge = pme_dev->dev->bus->self;
1724 /*
1725 * If bridge is in low power state, the
1726 * configuration space of subordinate devices
1727 * may be not accessible
1728 */
1729 if (bridge && bridge->current_state != PCI_D0)
1730 continue;
1731 pci_pme_wakeup(pme_dev->dev, NULL);
1732 } else {
1733 list_del(&pme_dev->list);
1734 kfree(pme_dev);
1735 }
1736 }
1737 if (!list_empty(&pci_pme_list))
1738 schedule_delayed_work(&pci_pme_work,
1739 msecs_to_jiffies(PME_TIMEOUT));
1740 mutex_unlock(&pci_pme_list_mutex);
1741}
1742
1743static void __pci_pme_active(struct pci_dev *dev, bool enable)
1744{
1745 u16 pmcsr;
1746
1747 if (!dev->pme_support)
1748 return;
1749
1750 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1751 /* Clear PME_Status by writing 1 to it and enable PME# */
1752 pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1753 if (!enable)
1754 pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1755
1756 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1757}
1758
1759/**
1760 * pci_pme_active - enable or disable PCI device's PME# function
1761 * @dev: PCI device to handle.
1762 * @enable: 'true' to enable PME# generation; 'false' to disable it.
1763 *
1764 * The caller must verify that the device is capable of generating PME# before
1765 * calling this function with @enable equal to 'true'.
1766 */
1767void pci_pme_active(struct pci_dev *dev, bool enable)
1768{
1769 __pci_pme_active(dev, enable);
1770
1771 /*
1772 * PCI (as opposed to PCIe) PME requires that the device have
1773 * its PME# line hooked up correctly. Not all hardware vendors
1774 * do this, so the PME never gets delivered and the device
1775 * remains asleep. The easiest way around this is to
1776 * periodically walk the list of suspended devices and check
1777 * whether any have their PME flag set. The assumption is that
1778 * we'll wake up often enough anyway that this won't be a huge
1779 * hit, and the power savings from the devices will still be a
1780 * win.
1781 *
1782 * Although PCIe uses in-band PME message instead of PME# line
1783 * to report PME, PME does not work for some PCIe devices in
1784 * reality. For example, there are devices that set their PME
1785 * status bits, but don't really bother to send a PME message;
1786 * there are PCI Express Root Ports that don't bother to
1787 * trigger interrupts when they receive PME messages from the
1788 * devices below. So PME poll is used for PCIe devices too.
1789 */
1790
1791 if (dev->pme_poll) {
1792 struct pci_pme_device *pme_dev;
1793 if (enable) {
1794 pme_dev = kmalloc(sizeof(struct pci_pme_device),
1795 GFP_KERNEL);
1796 if (!pme_dev) {
1797 dev_warn(&dev->dev, "can't enable PME#\n");
1798 return;
1799 }
1800 pme_dev->dev = dev;
1801 mutex_lock(&pci_pme_list_mutex);
1802 list_add(&pme_dev->list, &pci_pme_list);
1803 if (list_is_singular(&pci_pme_list))
1804 schedule_delayed_work(&pci_pme_work,
1805 msecs_to_jiffies(PME_TIMEOUT));
1806 mutex_unlock(&pci_pme_list_mutex);
1807 } else {
1808 mutex_lock(&pci_pme_list_mutex);
1809 list_for_each_entry(pme_dev, &pci_pme_list, list) {
1810 if (pme_dev->dev == dev) {
1811 list_del(&pme_dev->list);
1812 kfree(pme_dev);
1813 break;
1814 }
1815 }
1816 mutex_unlock(&pci_pme_list_mutex);
1817 }
1818 }
1819
1820 dev_dbg(&dev->dev, "PME# %s\n", enable ? "enabled" : "disabled");
1821}
1822EXPORT_SYMBOL(pci_pme_active);
1823
1824/**
1825 * __pci_enable_wake - enable PCI device as wakeup event source
1826 * @dev: PCI device affected
1827 * @state: PCI state from which device will issue wakeup events
1828 * @runtime: True if the events are to be generated at run time
1829 * @enable: True to enable event generation; false to disable
1830 *
1831 * This enables the device as a wakeup event source, or disables it.
1832 * When such events involves platform-specific hooks, those hooks are
1833 * called automatically by this routine.
1834 *
1835 * Devices with legacy power management (no standard PCI PM capabilities)
1836 * always require such platform hooks.
1837 *
1838 * RETURN VALUE:
1839 * 0 is returned on success
1840 * -EINVAL is returned if device is not supposed to wake up the system
1841 * Error code depending on the platform is returned if both the platform and
1842 * the native mechanism fail to enable the generation of wake-up events
1843 */
1844int __pci_enable_wake(struct pci_dev *dev, pci_power_t state,
1845 bool runtime, bool enable)
1846{
1847 int ret = 0;
1848
1849 if (enable && !runtime && !device_may_wakeup(&dev->dev))
1850 return -EINVAL;
1851
1852 /* Don't do the same thing twice in a row for one device. */
1853 if (!!enable == !!dev->wakeup_prepared)
1854 return 0;
1855
1856 /*
1857 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1858 * Anderson we should be doing PME# wake enable followed by ACPI wake
1859 * enable. To disable wake-up we call the platform first, for symmetry.
1860 */
1861
1862 if (enable) {
1863 int error;
1864
1865 if (pci_pme_capable(dev, state))
1866 pci_pme_active(dev, true);
1867 else
1868 ret = 1;
1869 error = runtime ? platform_pci_run_wake(dev, true) :
1870 platform_pci_sleep_wake(dev, true);
1871 if (ret)
1872 ret = error;
1873 if (!ret)
1874 dev->wakeup_prepared = true;
1875 } else {
1876 if (runtime)
1877 platform_pci_run_wake(dev, false);
1878 else
1879 platform_pci_sleep_wake(dev, false);
1880 pci_pme_active(dev, false);
1881 dev->wakeup_prepared = false;
1882 }
1883
1884 return ret;
1885}
1886EXPORT_SYMBOL(__pci_enable_wake);
1887
1888/**
1889 * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1890 * @dev: PCI device to prepare
1891 * @enable: True to enable wake-up event generation; false to disable
1892 *
1893 * Many drivers want the device to wake up the system from D3_hot or D3_cold
1894 * and this function allows them to set that up cleanly - pci_enable_wake()
1895 * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1896 * ordering constraints.
1897 *
1898 * This function only returns error code if the device is not capable of
1899 * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1900 * enable wake-up power for it.
1901 */
1902int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1903{
1904 return pci_pme_capable(dev, PCI_D3cold) ?
1905 pci_enable_wake(dev, PCI_D3cold, enable) :
1906 pci_enable_wake(dev, PCI_D3hot, enable);
1907}
1908EXPORT_SYMBOL(pci_wake_from_d3);
1909
1910/**
1911 * pci_target_state - find an appropriate low power state for a given PCI dev
1912 * @dev: PCI device
1913 *
1914 * Use underlying platform code to find a supported low power state for @dev.
1915 * If the platform can't manage @dev, return the deepest state from which it
1916 * can generate wake events, based on any available PME info.
1917 */
1918static pci_power_t pci_target_state(struct pci_dev *dev)
1919{
1920 pci_power_t target_state = PCI_D3hot;
1921
1922 if (platform_pci_power_manageable(dev)) {
1923 /*
1924 * Call the platform to choose the target state of the device
1925 * and enable wake-up from this state if supported.
1926 */
1927 pci_power_t state = platform_pci_choose_state(dev);
1928
1929 switch (state) {
1930 case PCI_POWER_ERROR:
1931 case PCI_UNKNOWN:
1932 break;
1933 case PCI_D1:
1934 case PCI_D2:
1935 if (pci_no_d1d2(dev))
1936 break;
1937 default:
1938 target_state = state;
1939 }
1940 } else if (!dev->pm_cap) {
1941 target_state = PCI_D0;
1942 } else if (device_may_wakeup(&dev->dev)) {
1943 /*
1944 * Find the deepest state from which the device can generate
1945 * wake-up events, make it the target state and enable device
1946 * to generate PME#.
1947 */
1948 if (dev->pme_support) {
1949 while (target_state
1950 && !(dev->pme_support & (1 << target_state)))
1951 target_state--;
1952 }
1953 }
1954
1955 return target_state;
1956}
1957
1958/**
1959 * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1960 * @dev: Device to handle.
1961 *
1962 * Choose the power state appropriate for the device depending on whether
1963 * it can wake up the system and/or is power manageable by the platform
1964 * (PCI_D3hot is the default) and put the device into that state.
1965 */
1966int pci_prepare_to_sleep(struct pci_dev *dev)
1967{
1968 pci_power_t target_state = pci_target_state(dev);
1969 int error;
1970
1971 if (target_state == PCI_POWER_ERROR)
1972 return -EIO;
1973
1974 pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
1975
1976 error = pci_set_power_state(dev, target_state);
1977
1978 if (error)
1979 pci_enable_wake(dev, target_state, false);
1980
1981 return error;
1982}
1983EXPORT_SYMBOL(pci_prepare_to_sleep);
1984
1985/**
1986 * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1987 * @dev: Device to handle.
1988 *
1989 * Disable device's system wake-up capability and put it into D0.
1990 */
1991int pci_back_from_sleep(struct pci_dev *dev)
1992{
1993 pci_enable_wake(dev, PCI_D0, false);
1994 return pci_set_power_state(dev, PCI_D0);
1995}
1996EXPORT_SYMBOL(pci_back_from_sleep);
1997
1998/**
1999 * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend.
2000 * @dev: PCI device being suspended.
2001 *
2002 * Prepare @dev to generate wake-up events at run time and put it into a low
2003 * power state.
2004 */
2005int pci_finish_runtime_suspend(struct pci_dev *dev)
2006{
2007 pci_power_t target_state = pci_target_state(dev);
2008 int error;
2009
2010 if (target_state == PCI_POWER_ERROR)
2011 return -EIO;
2012
2013 dev->runtime_d3cold = target_state == PCI_D3cold;
2014
2015 __pci_enable_wake(dev, target_state, true, pci_dev_run_wake(dev));
2016
2017 error = pci_set_power_state(dev, target_state);
2018
2019 if (error) {
2020 __pci_enable_wake(dev, target_state, true, false);
2021 dev->runtime_d3cold = false;
2022 }
2023
2024 return error;
2025}
2026
2027/**
2028 * pci_dev_run_wake - Check if device can generate run-time wake-up events.
2029 * @dev: Device to check.
2030 *
2031 * Return true if the device itself is capable of generating wake-up events
2032 * (through the platform or using the native PCIe PME) or if the device supports
2033 * PME and one of its upstream bridges can generate wake-up events.
2034 */
2035bool pci_dev_run_wake(struct pci_dev *dev)
2036{
2037 struct pci_bus *bus = dev->bus;
2038
2039 if (device_run_wake(&dev->dev))
2040 return true;
2041
2042 if (!dev->pme_support)
2043 return false;
2044
2045 while (bus->parent) {
2046 struct pci_dev *bridge = bus->self;
2047
2048 if (device_run_wake(&bridge->dev))
2049 return true;
2050
2051 bus = bus->parent;
2052 }
2053
2054 /* We have reached the root bus. */
2055 if (bus->bridge)
2056 return device_run_wake(bus->bridge);
2057
2058 return false;
2059}
2060EXPORT_SYMBOL_GPL(pci_dev_run_wake);
2061
2062/**
2063 * pci_dev_keep_suspended - Check if the device can stay in the suspended state.
2064 * @pci_dev: Device to check.
2065 *
2066 * Return 'true' if the device is runtime-suspended, it doesn't have to be
2067 * reconfigured due to wakeup settings difference between system and runtime
2068 * suspend and the current power state of it is suitable for the upcoming
2069 * (system) transition.
2070 *
2071 * If the device is not configured for system wakeup, disable PME for it before
2072 * returning 'true' to prevent it from waking up the system unnecessarily.
2073 */
2074bool pci_dev_keep_suspended(struct pci_dev *pci_dev)
2075{
2076 struct device *dev = &pci_dev->dev;
2077
2078 if (!pm_runtime_suspended(dev)
2079 || pci_target_state(pci_dev) != pci_dev->current_state
2080 || platform_pci_need_resume(pci_dev))
2081 return false;
2082
2083 /*
2084 * At this point the device is good to go unless it's been configured
2085 * to generate PME at the runtime suspend time, but it is not supposed
2086 * to wake up the system. In that case, simply disable PME for it
2087 * (it will have to be re-enabled on exit from system resume).
2088 *
2089 * If the device's power state is D3cold and the platform check above
2090 * hasn't triggered, the device's configuration is suitable and we don't
2091 * need to manipulate it at all.
2092 */
2093 spin_lock_irq(&dev->power.lock);
2094
2095 if (pm_runtime_suspended(dev) && pci_dev->current_state < PCI_D3cold &&
2096 !device_may_wakeup(dev))
2097 __pci_pme_active(pci_dev, false);
2098
2099 spin_unlock_irq(&dev->power.lock);
2100 return true;
2101}
2102
2103/**
2104 * pci_dev_complete_resume - Finalize resume from system sleep for a device.
2105 * @pci_dev: Device to handle.
2106 *
2107 * If the device is runtime suspended and wakeup-capable, enable PME for it as
2108 * it might have been disabled during the prepare phase of system suspend if
2109 * the device was not configured for system wakeup.
2110 */
2111void pci_dev_complete_resume(struct pci_dev *pci_dev)
2112{
2113 struct device *dev = &pci_dev->dev;
2114
2115 if (!pci_dev_run_wake(pci_dev))
2116 return;
2117
2118 spin_lock_irq(&dev->power.lock);
2119
2120 if (pm_runtime_suspended(dev) && pci_dev->current_state < PCI_D3cold)
2121 __pci_pme_active(pci_dev, true);
2122
2123 spin_unlock_irq(&dev->power.lock);
2124}
2125
2126void pci_config_pm_runtime_get(struct pci_dev *pdev)
2127{
2128 struct device *dev = &pdev->dev;
2129 struct device *parent = dev->parent;
2130
2131 if (parent)
2132 pm_runtime_get_sync(parent);
2133 pm_runtime_get_noresume(dev);
2134 /*
2135 * pdev->current_state is set to PCI_D3cold during suspending,
2136 * so wait until suspending completes
2137 */
2138 pm_runtime_barrier(dev);
2139 /*
2140 * Only need to resume devices in D3cold, because config
2141 * registers are still accessible for devices suspended but
2142 * not in D3cold.
2143 */
2144 if (pdev->current_state == PCI_D3cold)
2145 pm_runtime_resume(dev);
2146}
2147
2148void pci_config_pm_runtime_put(struct pci_dev *pdev)
2149{
2150 struct device *dev = &pdev->dev;
2151 struct device *parent = dev->parent;
2152
2153 pm_runtime_put(dev);
2154 if (parent)
2155 pm_runtime_put_sync(parent);
2156}
2157
2158/**
2159 * pci_pm_init - Initialize PM functions of given PCI device
2160 * @dev: PCI device to handle.
2161 */
2162void pci_pm_init(struct pci_dev *dev)
2163{
2164 int pm;
2165 u16 pmc;
2166
2167 pm_runtime_forbid(&dev->dev);
2168 pm_runtime_set_active(&dev->dev);
2169 pm_runtime_enable(&dev->dev);
2170 device_enable_async_suspend(&dev->dev);
2171 dev->wakeup_prepared = false;
2172
2173 dev->pm_cap = 0;
2174 dev->pme_support = 0;
2175
2176 /* find PCI PM capability in list */
2177 pm = pci_find_capability(dev, PCI_CAP_ID_PM);
2178 if (!pm)
2179 return;
2180 /* Check device's ability to generate PME# */
2181 pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
2182
2183 if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
2184 dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
2185 pmc & PCI_PM_CAP_VER_MASK);
2186 return;
2187 }
2188
2189 dev->pm_cap = pm;
2190 dev->d3_delay = PCI_PM_D3_WAIT;
2191 dev->d3cold_delay = PCI_PM_D3COLD_WAIT;
2192 dev->d3cold_allowed = true;
2193
2194 dev->d1_support = false;
2195 dev->d2_support = false;
2196 if (!pci_no_d1d2(dev)) {
2197 if (pmc & PCI_PM_CAP_D1)
2198 dev->d1_support = true;
2199 if (pmc & PCI_PM_CAP_D2)
2200 dev->d2_support = true;
2201
2202 if (dev->d1_support || dev->d2_support)
2203 dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
2204 dev->d1_support ? " D1" : "",
2205 dev->d2_support ? " D2" : "");
2206 }
2207
2208 pmc &= PCI_PM_CAP_PME_MASK;
2209 if (pmc) {
2210 dev_printk(KERN_DEBUG, &dev->dev,
2211 "PME# supported from%s%s%s%s%s\n",
2212 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
2213 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
2214 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
2215 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
2216 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
2217 dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
2218 dev->pme_poll = true;
2219 /*
2220 * Make device's PM flags reflect the wake-up capability, but
2221 * let the user space enable it to wake up the system as needed.
2222 */
2223 device_set_wakeup_capable(&dev->dev, true);
2224 /* Disable the PME# generation functionality */
2225 pci_pme_active(dev, false);
2226 }
2227}
2228
2229static unsigned long pci_ea_flags(struct pci_dev *dev, u8 prop)
2230{
2231 unsigned long flags = IORESOURCE_PCI_FIXED;
2232
2233 switch (prop) {
2234 case PCI_EA_P_MEM:
2235 case PCI_EA_P_VF_MEM:
2236 flags |= IORESOURCE_MEM;
2237 break;
2238 case PCI_EA_P_MEM_PREFETCH:
2239 case PCI_EA_P_VF_MEM_PREFETCH:
2240 flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
2241 break;
2242 case PCI_EA_P_IO:
2243 flags |= IORESOURCE_IO;
2244 break;
2245 default:
2246 return 0;
2247 }
2248
2249 return flags;
2250}
2251
2252static struct resource *pci_ea_get_resource(struct pci_dev *dev, u8 bei,
2253 u8 prop)
2254{
2255 if (bei <= PCI_EA_BEI_BAR5 && prop <= PCI_EA_P_IO)
2256 return &dev->resource[bei];
2257#ifdef CONFIG_PCI_IOV
2258 else if (bei >= PCI_EA_BEI_VF_BAR0 && bei <= PCI_EA_BEI_VF_BAR5 &&
2259 (prop == PCI_EA_P_VF_MEM || prop == PCI_EA_P_VF_MEM_PREFETCH))
2260 return &dev->resource[PCI_IOV_RESOURCES +
2261 bei - PCI_EA_BEI_VF_BAR0];
2262#endif
2263 else if (bei == PCI_EA_BEI_ROM)
2264 return &dev->resource[PCI_ROM_RESOURCE];
2265 else
2266 return NULL;
2267}
2268
2269/* Read an Enhanced Allocation (EA) entry */
2270static int pci_ea_read(struct pci_dev *dev, int offset)
2271{
2272 struct resource *res;
2273 int ent_size, ent_offset = offset;
2274 resource_size_t start, end;
2275 unsigned long flags;
2276 u32 dw0, bei, base, max_offset;
2277 u8 prop;
2278 bool support_64 = (sizeof(resource_size_t) >= 8);
2279
2280 pci_read_config_dword(dev, ent_offset, &dw0);
2281 ent_offset += 4;
2282
2283 /* Entry size field indicates DWORDs after 1st */
2284 ent_size = ((dw0 & PCI_EA_ES) + 1) << 2;
2285
2286 if (!(dw0 & PCI_EA_ENABLE)) /* Entry not enabled */
2287 goto out;
2288
2289 bei = (dw0 & PCI_EA_BEI) >> 4;
2290 prop = (dw0 & PCI_EA_PP) >> 8;
2291
2292 /*
2293 * If the Property is in the reserved range, try the Secondary
2294 * Property instead.
2295 */
2296 if (prop > PCI_EA_P_BRIDGE_IO && prop < PCI_EA_P_MEM_RESERVED)
2297 prop = (dw0 & PCI_EA_SP) >> 16;
2298 if (prop > PCI_EA_P_BRIDGE_IO)
2299 goto out;
2300
2301 res = pci_ea_get_resource(dev, bei, prop);
2302 if (!res) {
2303 dev_err(&dev->dev, "Unsupported EA entry BEI: %u\n", bei);
2304 goto out;
2305 }
2306
2307 flags = pci_ea_flags(dev, prop);
2308 if (!flags) {
2309 dev_err(&dev->dev, "Unsupported EA properties: %#x\n", prop);
2310 goto out;
2311 }
2312
2313 /* Read Base */
2314 pci_read_config_dword(dev, ent_offset, &base);
2315 start = (base & PCI_EA_FIELD_MASK);
2316 ent_offset += 4;
2317
2318 /* Read MaxOffset */
2319 pci_read_config_dword(dev, ent_offset, &max_offset);
2320 ent_offset += 4;
2321
2322 /* Read Base MSBs (if 64-bit entry) */
2323 if (base & PCI_EA_IS_64) {
2324 u32 base_upper;
2325
2326 pci_read_config_dword(dev, ent_offset, &base_upper);
2327 ent_offset += 4;
2328
2329 flags |= IORESOURCE_MEM_64;
2330
2331 /* entry starts above 32-bit boundary, can't use */
2332 if (!support_64 && base_upper)
2333 goto out;
2334
2335 if (support_64)
2336 start |= ((u64)base_upper << 32);
2337 }
2338
2339 end = start + (max_offset | 0x03);
2340
2341 /* Read MaxOffset MSBs (if 64-bit entry) */
2342 if (max_offset & PCI_EA_IS_64) {
2343 u32 max_offset_upper;
2344
2345 pci_read_config_dword(dev, ent_offset, &max_offset_upper);
2346 ent_offset += 4;
2347
2348 flags |= IORESOURCE_MEM_64;
2349
2350 /* entry too big, can't use */
2351 if (!support_64 && max_offset_upper)
2352 goto out;
2353
2354 if (support_64)
2355 end += ((u64)max_offset_upper << 32);
2356 }
2357
2358 if (end < start) {
2359 dev_err(&dev->dev, "EA Entry crosses address boundary\n");
2360 goto out;
2361 }
2362
2363 if (ent_size != ent_offset - offset) {
2364 dev_err(&dev->dev,
2365 "EA Entry Size (%d) does not match length read (%d)\n",
2366 ent_size, ent_offset - offset);
2367 goto out;
2368 }
2369
2370 res->name = pci_name(dev);
2371 res->start = start;
2372 res->end = end;
2373 res->flags = flags;
2374
2375 if (bei <= PCI_EA_BEI_BAR5)
2376 dev_printk(KERN_DEBUG, &dev->dev, "BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
2377 bei, res, prop);
2378 else if (bei == PCI_EA_BEI_ROM)
2379 dev_printk(KERN_DEBUG, &dev->dev, "ROM: %pR (from Enhanced Allocation, properties %#02x)\n",
2380 res, prop);
2381 else if (bei >= PCI_EA_BEI_VF_BAR0 && bei <= PCI_EA_BEI_VF_BAR5)
2382 dev_printk(KERN_DEBUG, &dev->dev, "VF BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
2383 bei - PCI_EA_BEI_VF_BAR0, res, prop);
2384 else
2385 dev_printk(KERN_DEBUG, &dev->dev, "BEI %d res: %pR (from Enhanced Allocation, properties %#02x)\n",
2386 bei, res, prop);
2387
2388out:
2389 return offset + ent_size;
2390}
2391
2392/* Enhanced Allocation Initalization */
2393void pci_ea_init(struct pci_dev *dev)
2394{
2395 int ea;
2396 u8 num_ent;
2397 int offset;
2398 int i;
2399
2400 /* find PCI EA capability in list */
2401 ea = pci_find_capability(dev, PCI_CAP_ID_EA);
2402 if (!ea)
2403 return;
2404
2405 /* determine the number of entries */
2406 pci_bus_read_config_byte(dev->bus, dev->devfn, ea + PCI_EA_NUM_ENT,
2407 &num_ent);
2408 num_ent &= PCI_EA_NUM_ENT_MASK;
2409
2410 offset = ea + PCI_EA_FIRST_ENT;
2411
2412 /* Skip DWORD 2 for type 1 functions */
2413 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
2414 offset += 4;
2415
2416 /* parse each EA entry */
2417 for (i = 0; i < num_ent; ++i)
2418 offset = pci_ea_read(dev, offset);
2419}
2420
2421static void pci_add_saved_cap(struct pci_dev *pci_dev,
2422 struct pci_cap_saved_state *new_cap)
2423{
2424 hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space);
2425}
2426
2427/**
2428 * _pci_add_cap_save_buffer - allocate buffer for saving given
2429 * capability registers
2430 * @dev: the PCI device
2431 * @cap: the capability to allocate the buffer for
2432 * @extended: Standard or Extended capability ID
2433 * @size: requested size of the buffer
2434 */
2435static int _pci_add_cap_save_buffer(struct pci_dev *dev, u16 cap,
2436 bool extended, unsigned int size)
2437{
2438 int pos;
2439 struct pci_cap_saved_state *save_state;
2440
2441 if (extended)
2442 pos = pci_find_ext_capability(dev, cap);
2443 else
2444 pos = pci_find_capability(dev, cap);
2445
2446 if (!pos)
2447 return 0;
2448
2449 save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
2450 if (!save_state)
2451 return -ENOMEM;
2452
2453 save_state->cap.cap_nr = cap;
2454 save_state->cap.cap_extended = extended;
2455 save_state->cap.size = size;
2456 pci_add_saved_cap(dev, save_state);
2457
2458 return 0;
2459}
2460
2461int pci_add_cap_save_buffer(struct pci_dev *dev, char cap, unsigned int size)
2462{
2463 return _pci_add_cap_save_buffer(dev, cap, false, size);
2464}
2465
2466int pci_add_ext_cap_save_buffer(struct pci_dev *dev, u16 cap, unsigned int size)
2467{
2468 return _pci_add_cap_save_buffer(dev, cap, true, size);
2469}
2470
2471/**
2472 * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
2473 * @dev: the PCI device
2474 */
2475void pci_allocate_cap_save_buffers(struct pci_dev *dev)
2476{
2477 int error;
2478
2479 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
2480 PCI_EXP_SAVE_REGS * sizeof(u16));
2481 if (error)
2482 dev_err(&dev->dev,
2483 "unable to preallocate PCI Express save buffer\n");
2484
2485 error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
2486 if (error)
2487 dev_err(&dev->dev,
2488 "unable to preallocate PCI-X save buffer\n");
2489
2490 pci_allocate_vc_save_buffers(dev);
2491}
2492
2493void pci_free_cap_save_buffers(struct pci_dev *dev)
2494{
2495 struct pci_cap_saved_state *tmp;
2496 struct hlist_node *n;
2497
2498 hlist_for_each_entry_safe(tmp, n, &dev->saved_cap_space, next)
2499 kfree(tmp);
2500}
2501
2502/**
2503 * pci_configure_ari - enable or disable ARI forwarding
2504 * @dev: the PCI device
2505 *
2506 * If @dev and its upstream bridge both support ARI, enable ARI in the
2507 * bridge. Otherwise, disable ARI in the bridge.
2508 */
2509void pci_configure_ari(struct pci_dev *dev)
2510{
2511 u32 cap;
2512 struct pci_dev *bridge;
2513
2514 if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn)
2515 return;
2516
2517 bridge = dev->bus->self;
2518 if (!bridge)
2519 return;
2520
2521 pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap);
2522 if (!(cap & PCI_EXP_DEVCAP2_ARI))
2523 return;
2524
2525 if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) {
2526 pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2,
2527 PCI_EXP_DEVCTL2_ARI);
2528 bridge->ari_enabled = 1;
2529 } else {
2530 pcie_capability_clear_word(bridge, PCI_EXP_DEVCTL2,
2531 PCI_EXP_DEVCTL2_ARI);
2532 bridge->ari_enabled = 0;
2533 }
2534}
2535
2536static int pci_acs_enable;
2537
2538/**
2539 * pci_request_acs - ask for ACS to be enabled if supported
2540 */
2541void pci_request_acs(void)
2542{
2543 pci_acs_enable = 1;
2544}
2545
2546/**
2547 * pci_std_enable_acs - enable ACS on devices using standard ACS capabilites
2548 * @dev: the PCI device
2549 */
2550static int pci_std_enable_acs(struct pci_dev *dev)
2551{
2552 int pos;
2553 u16 cap;
2554 u16 ctrl;
2555
2556 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
2557 if (!pos)
2558 return -ENODEV;
2559
2560 pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
2561 pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
2562
2563 /* Source Validation */
2564 ctrl |= (cap & PCI_ACS_SV);
2565
2566 /* P2P Request Redirect */
2567 ctrl |= (cap & PCI_ACS_RR);
2568
2569 /* P2P Completion Redirect */
2570 ctrl |= (cap & PCI_ACS_CR);
2571
2572 /* Upstream Forwarding */
2573 ctrl |= (cap & PCI_ACS_UF);
2574
2575 pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
2576
2577 return 0;
2578}
2579
2580/**
2581 * pci_enable_acs - enable ACS if hardware support it
2582 * @dev: the PCI device
2583 */
2584void pci_enable_acs(struct pci_dev *dev)
2585{
2586 if (!pci_acs_enable)
2587 return;
2588
2589 if (!pci_std_enable_acs(dev))
2590 return;
2591
2592 pci_dev_specific_enable_acs(dev);
2593}
2594
2595static bool pci_acs_flags_enabled(struct pci_dev *pdev, u16 acs_flags)
2596{
2597 int pos;
2598 u16 cap, ctrl;
2599
2600 pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ACS);
2601 if (!pos)
2602 return false;
2603
2604 /*
2605 * Except for egress control, capabilities are either required
2606 * or only required if controllable. Features missing from the
2607 * capability field can therefore be assumed as hard-wired enabled.
2608 */
2609 pci_read_config_word(pdev, pos + PCI_ACS_CAP, &cap);
2610 acs_flags &= (cap | PCI_ACS_EC);
2611
2612 pci_read_config_word(pdev, pos + PCI_ACS_CTRL, &ctrl);
2613 return (ctrl & acs_flags) == acs_flags;
2614}
2615
2616/**
2617 * pci_acs_enabled - test ACS against required flags for a given device
2618 * @pdev: device to test
2619 * @acs_flags: required PCI ACS flags
2620 *
2621 * Return true if the device supports the provided flags. Automatically
2622 * filters out flags that are not implemented on multifunction devices.
2623 *
2624 * Note that this interface checks the effective ACS capabilities of the
2625 * device rather than the actual capabilities. For instance, most single
2626 * function endpoints are not required to support ACS because they have no
2627 * opportunity for peer-to-peer access. We therefore return 'true'
2628 * regardless of whether the device exposes an ACS capability. This makes
2629 * it much easier for callers of this function to ignore the actual type
2630 * or topology of the device when testing ACS support.
2631 */
2632bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags)
2633{
2634 int ret;
2635
2636 ret = pci_dev_specific_acs_enabled(pdev, acs_flags);
2637 if (ret >= 0)
2638 return ret > 0;
2639
2640 /*
2641 * Conventional PCI and PCI-X devices never support ACS, either
2642 * effectively or actually. The shared bus topology implies that
2643 * any device on the bus can receive or snoop DMA.
2644 */
2645 if (!pci_is_pcie(pdev))
2646 return false;
2647
2648 switch (pci_pcie_type(pdev)) {
2649 /*
2650 * PCI/X-to-PCIe bridges are not specifically mentioned by the spec,
2651 * but since their primary interface is PCI/X, we conservatively
2652 * handle them as we would a non-PCIe device.
2653 */
2654 case PCI_EXP_TYPE_PCIE_BRIDGE:
2655 /*
2656 * PCIe 3.0, 6.12.1 excludes ACS on these devices. "ACS is never
2657 * applicable... must never implement an ACS Extended Capability...".
2658 * This seems arbitrary, but we take a conservative interpretation
2659 * of this statement.
2660 */
2661 case PCI_EXP_TYPE_PCI_BRIDGE:
2662 case PCI_EXP_TYPE_RC_EC:
2663 return false;
2664 /*
2665 * PCIe 3.0, 6.12.1.1 specifies that downstream and root ports should
2666 * implement ACS in order to indicate their peer-to-peer capabilities,
2667 * regardless of whether they are single- or multi-function devices.
2668 */
2669 case PCI_EXP_TYPE_DOWNSTREAM:
2670 case PCI_EXP_TYPE_ROOT_PORT:
2671 return pci_acs_flags_enabled(pdev, acs_flags);
2672 /*
2673 * PCIe 3.0, 6.12.1.2 specifies ACS capabilities that should be
2674 * implemented by the remaining PCIe types to indicate peer-to-peer
2675 * capabilities, but only when they are part of a multifunction
2676 * device. The footnote for section 6.12 indicates the specific
2677 * PCIe types included here.
2678 */
2679 case PCI_EXP_TYPE_ENDPOINT:
2680 case PCI_EXP_TYPE_UPSTREAM:
2681 case PCI_EXP_TYPE_LEG_END:
2682 case PCI_EXP_TYPE_RC_END:
2683 if (!pdev->multifunction)
2684 break;
2685
2686 return pci_acs_flags_enabled(pdev, acs_flags);
2687 }
2688
2689 /*
2690 * PCIe 3.0, 6.12.1.3 specifies no ACS capabilities are applicable
2691 * to single function devices with the exception of downstream ports.
2692 */
2693 return true;
2694}
2695
2696/**
2697 * pci_acs_path_enable - test ACS flags from start to end in a hierarchy
2698 * @start: starting downstream device
2699 * @end: ending upstream device or NULL to search to the root bus
2700 * @acs_flags: required flags
2701 *
2702 * Walk up a device tree from start to end testing PCI ACS support. If
2703 * any step along the way does not support the required flags, return false.
2704 */
2705bool pci_acs_path_enabled(struct pci_dev *start,
2706 struct pci_dev *end, u16 acs_flags)
2707{
2708 struct pci_dev *pdev, *parent = start;
2709
2710 do {
2711 pdev = parent;
2712
2713 if (!pci_acs_enabled(pdev, acs_flags))
2714 return false;
2715
2716 if (pci_is_root_bus(pdev->bus))
2717 return (end == NULL);
2718
2719 parent = pdev->bus->self;
2720 } while (pdev != end);
2721
2722 return true;
2723}
2724
2725/**
2726 * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
2727 * @dev: the PCI device
2728 * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTC, 4=INTD)
2729 *
2730 * Perform INTx swizzling for a device behind one level of bridge. This is
2731 * required by section 9.1 of the PCI-to-PCI bridge specification for devices
2732 * behind bridges on add-in cards. For devices with ARI enabled, the slot
2733 * number is always 0 (see the Implementation Note in section 2.2.8.1 of
2734 * the PCI Express Base Specification, Revision 2.1)
2735 */
2736u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin)
2737{
2738 int slot;
2739
2740 if (pci_ari_enabled(dev->bus))
2741 slot = 0;
2742 else
2743 slot = PCI_SLOT(dev->devfn);
2744
2745 return (((pin - 1) + slot) % 4) + 1;
2746}
2747
2748int pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
2749{
2750 u8 pin;
2751
2752 pin = dev->pin;
2753 if (!pin)
2754 return -1;
2755
2756 while (!pci_is_root_bus(dev->bus)) {
2757 pin = pci_swizzle_interrupt_pin(dev, pin);
2758 dev = dev->bus->self;
2759 }
2760 *bridge = dev;
2761 return pin;
2762}
2763
2764/**
2765 * pci_common_swizzle - swizzle INTx all the way to root bridge
2766 * @dev: the PCI device
2767 * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
2768 *
2769 * Perform INTx swizzling for a device. This traverses through all PCI-to-PCI
2770 * bridges all the way up to a PCI root bus.
2771 */
2772u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
2773{
2774 u8 pin = *pinp;
2775
2776 while (!pci_is_root_bus(dev->bus)) {
2777 pin = pci_swizzle_interrupt_pin(dev, pin);
2778 dev = dev->bus->self;
2779 }
2780 *pinp = pin;
2781 return PCI_SLOT(dev->devfn);
2782}
2783EXPORT_SYMBOL_GPL(pci_common_swizzle);
2784
2785/**
2786 * pci_release_region - Release a PCI bar
2787 * @pdev: PCI device whose resources were previously reserved by pci_request_region
2788 * @bar: BAR to release
2789 *
2790 * Releases the PCI I/O and memory resources previously reserved by a
2791 * successful call to pci_request_region. Call this function only
2792 * after all use of the PCI regions has ceased.
2793 */
2794void pci_release_region(struct pci_dev *pdev, int bar)
2795{
2796 struct pci_devres *dr;
2797
2798 if (pci_resource_len(pdev, bar) == 0)
2799 return;
2800 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
2801 release_region(pci_resource_start(pdev, bar),
2802 pci_resource_len(pdev, bar));
2803 else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
2804 release_mem_region(pci_resource_start(pdev, bar),
2805 pci_resource_len(pdev, bar));
2806
2807 dr = find_pci_dr(pdev);
2808 if (dr)
2809 dr->region_mask &= ~(1 << bar);
2810}
2811EXPORT_SYMBOL(pci_release_region);
2812
2813/**
2814 * __pci_request_region - Reserved PCI I/O and memory resource
2815 * @pdev: PCI device whose resources are to be reserved
2816 * @bar: BAR to be reserved
2817 * @res_name: Name to be associated with resource.
2818 * @exclusive: whether the region access is exclusive or not
2819 *
2820 * Mark the PCI region associated with PCI device @pdev BR @bar as
2821 * being reserved by owner @res_name. Do not access any
2822 * address inside the PCI regions unless this call returns
2823 * successfully.
2824 *
2825 * If @exclusive is set, then the region is marked so that userspace
2826 * is explicitly not allowed to map the resource via /dev/mem or
2827 * sysfs MMIO access.
2828 *
2829 * Returns 0 on success, or %EBUSY on error. A warning
2830 * message is also printed on failure.
2831 */
2832static int __pci_request_region(struct pci_dev *pdev, int bar,
2833 const char *res_name, int exclusive)
2834{
2835 struct pci_devres *dr;
2836
2837 if (pci_resource_len(pdev, bar) == 0)
2838 return 0;
2839
2840 if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
2841 if (!request_region(pci_resource_start(pdev, bar),
2842 pci_resource_len(pdev, bar), res_name))
2843 goto err_out;
2844 } else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
2845 if (!__request_mem_region(pci_resource_start(pdev, bar),
2846 pci_resource_len(pdev, bar), res_name,
2847 exclusive))
2848 goto err_out;
2849 }
2850
2851 dr = find_pci_dr(pdev);
2852 if (dr)
2853 dr->region_mask |= 1 << bar;
2854
2855 return 0;
2856
2857err_out:
2858 dev_warn(&pdev->dev, "BAR %d: can't reserve %pR\n", bar,
2859 &pdev->resource[bar]);
2860 return -EBUSY;
2861}
2862
2863/**
2864 * pci_request_region - Reserve PCI I/O and memory resource
2865 * @pdev: PCI device whose resources are to be reserved
2866 * @bar: BAR to be reserved
2867 * @res_name: Name to be associated with resource
2868 *
2869 * Mark the PCI region associated with PCI device @pdev BAR @bar as
2870 * being reserved by owner @res_name. Do not access any
2871 * address inside the PCI regions unless this call returns
2872 * successfully.
2873 *
2874 * Returns 0 on success, or %EBUSY on error. A warning
2875 * message is also printed on failure.
2876 */
2877int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
2878{
2879 return __pci_request_region(pdev, bar, res_name, 0);
2880}
2881EXPORT_SYMBOL(pci_request_region);
2882
2883/**
2884 * pci_request_region_exclusive - Reserved PCI I/O and memory resource
2885 * @pdev: PCI device whose resources are to be reserved
2886 * @bar: BAR to be reserved
2887 * @res_name: Name to be associated with resource.
2888 *
2889 * Mark the PCI region associated with PCI device @pdev BR @bar as
2890 * being reserved by owner @res_name. Do not access any
2891 * address inside the PCI regions unless this call returns
2892 * successfully.
2893 *
2894 * Returns 0 on success, or %EBUSY on error. A warning
2895 * message is also printed on failure.
2896 *
2897 * The key difference that _exclusive makes it that userspace is
2898 * explicitly not allowed to map the resource via /dev/mem or
2899 * sysfs.
2900 */
2901int pci_request_region_exclusive(struct pci_dev *pdev, int bar,
2902 const char *res_name)
2903{
2904 return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
2905}
2906EXPORT_SYMBOL(pci_request_region_exclusive);
2907
2908/**
2909 * pci_release_selected_regions - Release selected PCI I/O and memory resources
2910 * @pdev: PCI device whose resources were previously reserved
2911 * @bars: Bitmask of BARs to be released
2912 *
2913 * Release selected PCI I/O and memory resources previously reserved.
2914 * Call this function only after all use of the PCI regions has ceased.
2915 */
2916void pci_release_selected_regions(struct pci_dev *pdev, int bars)
2917{
2918 int i;
2919
2920 for (i = 0; i < 6; i++)
2921 if (bars & (1 << i))
2922 pci_release_region(pdev, i);
2923}
2924EXPORT_SYMBOL(pci_release_selected_regions);
2925
2926static int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
2927 const char *res_name, int excl)
2928{
2929 int i;
2930
2931 for (i = 0; i < 6; i++)
2932 if (bars & (1 << i))
2933 if (__pci_request_region(pdev, i, res_name, excl))
2934 goto err_out;
2935 return 0;
2936
2937err_out:
2938 while (--i >= 0)
2939 if (bars & (1 << i))
2940 pci_release_region(pdev, i);
2941
2942 return -EBUSY;
2943}
2944
2945
2946/**
2947 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
2948 * @pdev: PCI device whose resources are to be reserved
2949 * @bars: Bitmask of BARs to be requested
2950 * @res_name: Name to be associated with resource
2951 */
2952int pci_request_selected_regions(struct pci_dev *pdev, int bars,
2953 const char *res_name)
2954{
2955 return __pci_request_selected_regions(pdev, bars, res_name, 0);
2956}
2957EXPORT_SYMBOL(pci_request_selected_regions);
2958
2959int pci_request_selected_regions_exclusive(struct pci_dev *pdev, int bars,
2960 const char *res_name)
2961{
2962 return __pci_request_selected_regions(pdev, bars, res_name,
2963 IORESOURCE_EXCLUSIVE);
2964}
2965EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
2966
2967/**
2968 * pci_release_regions - Release reserved PCI I/O and memory resources
2969 * @pdev: PCI device whose resources were previously reserved by pci_request_regions
2970 *
2971 * Releases all PCI I/O and memory resources previously reserved by a
2972 * successful call to pci_request_regions. Call this function only
2973 * after all use of the PCI regions has ceased.
2974 */
2975
2976void pci_release_regions(struct pci_dev *pdev)
2977{
2978 pci_release_selected_regions(pdev, (1 << 6) - 1);
2979}
2980EXPORT_SYMBOL(pci_release_regions);
2981
2982/**
2983 * pci_request_regions - Reserved PCI I/O and memory resources
2984 * @pdev: PCI device whose resources are to be reserved
2985 * @res_name: Name to be associated with resource.
2986 *
2987 * Mark all PCI regions associated with PCI device @pdev as
2988 * being reserved by owner @res_name. Do not access any
2989 * address inside the PCI regions unless this call returns
2990 * successfully.
2991 *
2992 * Returns 0 on success, or %EBUSY on error. A warning
2993 * message is also printed on failure.
2994 */
2995int pci_request_regions(struct pci_dev *pdev, const char *res_name)
2996{
2997 return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
2998}
2999EXPORT_SYMBOL(pci_request_regions);
3000
3001/**
3002 * pci_request_regions_exclusive - Reserved PCI I/O and memory resources
3003 * @pdev: PCI device whose resources are to be reserved
3004 * @res_name: Name to be associated with resource.
3005 *
3006 * Mark all PCI regions associated with PCI device @pdev as
3007 * being reserved by owner @res_name. Do not access any
3008 * address inside the PCI regions unless this call returns
3009 * successfully.
3010 *
3011 * pci_request_regions_exclusive() will mark the region so that
3012 * /dev/mem and the sysfs MMIO access will not be allowed.
3013 *
3014 * Returns 0 on success, or %EBUSY on error. A warning
3015 * message is also printed on failure.
3016 */
3017int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
3018{
3019 return pci_request_selected_regions_exclusive(pdev,
3020 ((1 << 6) - 1), res_name);
3021}
3022EXPORT_SYMBOL(pci_request_regions_exclusive);
3023
3024/**
3025 * pci_remap_iospace - Remap the memory mapped I/O space
3026 * @res: Resource describing the I/O space
3027 * @phys_addr: physical address of range to be mapped
3028 *
3029 * Remap the memory mapped I/O space described by the @res
3030 * and the CPU physical address @phys_addr into virtual address space.
3031 * Only architectures that have memory mapped IO functions defined
3032 * (and the PCI_IOBASE value defined) should call this function.
3033 */
3034int __weak pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
3035{
3036#if defined(PCI_IOBASE) && defined(CONFIG_MMU)
3037 unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start;
3038
3039 if (!(res->flags & IORESOURCE_IO))
3040 return -EINVAL;
3041
3042 if (res->end > IO_SPACE_LIMIT)
3043 return -EINVAL;
3044
3045 return ioremap_page_range(vaddr, vaddr + resource_size(res), phys_addr,
3046 pgprot_device(PAGE_KERNEL));
3047#else
3048 /* this architecture does not have memory mapped I/O space,
3049 so this function should never be called */
3050 WARN_ONCE(1, "This architecture does not support memory mapped I/O\n");
3051 return -ENODEV;
3052#endif
3053}
3054
3055static void __pci_set_master(struct pci_dev *dev, bool enable)
3056{
3057 u16 old_cmd, cmd;
3058
3059 pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
3060 if (enable)
3061 cmd = old_cmd | PCI_COMMAND_MASTER;
3062 else
3063 cmd = old_cmd & ~PCI_COMMAND_MASTER;
3064 if (cmd != old_cmd) {
3065 dev_dbg(&dev->dev, "%s bus mastering\n",
3066 enable ? "enabling" : "disabling");
3067 pci_write_config_word(dev, PCI_COMMAND, cmd);
3068 }
3069 dev->is_busmaster = enable;
3070}
3071
3072/**
3073 * pcibios_setup - process "pci=" kernel boot arguments
3074 * @str: string used to pass in "pci=" kernel boot arguments
3075 *
3076 * Process kernel boot arguments. This is the default implementation.
3077 * Architecture specific implementations can override this as necessary.
3078 */
3079char * __weak __init pcibios_setup(char *str)
3080{
3081 return str;
3082}
3083
3084/**
3085 * pcibios_set_master - enable PCI bus-mastering for device dev
3086 * @dev: the PCI device to enable
3087 *
3088 * Enables PCI bus-mastering for the device. This is the default
3089 * implementation. Architecture specific implementations can override
3090 * this if necessary.
3091 */
3092void __weak pcibios_set_master(struct pci_dev *dev)
3093{
3094 u8 lat;
3095
3096 /* The latency timer doesn't apply to PCIe (either Type 0 or Type 1) */
3097 if (pci_is_pcie(dev))
3098 return;
3099
3100 pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
3101 if (lat < 16)
3102 lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
3103 else if (lat > pcibios_max_latency)
3104 lat = pcibios_max_latency;
3105 else
3106 return;
3107
3108 pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
3109}
3110
3111/**
3112 * pci_set_master - enables bus-mastering for device dev
3113 * @dev: the PCI device to enable
3114 *
3115 * Enables bus-mastering on the device and calls pcibios_set_master()
3116 * to do the needed arch specific settings.
3117 */
3118void pci_set_master(struct pci_dev *dev)
3119{
3120 __pci_set_master(dev, true);
3121 pcibios_set_master(dev);
3122}
3123EXPORT_SYMBOL(pci_set_master);
3124
3125/**
3126 * pci_clear_master - disables bus-mastering for device dev
3127 * @dev: the PCI device to disable
3128 */
3129void pci_clear_master(struct pci_dev *dev)
3130{
3131 __pci_set_master(dev, false);
3132}
3133EXPORT_SYMBOL(pci_clear_master);
3134
3135/**
3136 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
3137 * @dev: the PCI device for which MWI is to be enabled
3138 *
3139 * Helper function for pci_set_mwi.
3140 * Originally copied from drivers/net/acenic.c.
3141 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
3142 *
3143 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
3144 */
3145int pci_set_cacheline_size(struct pci_dev *dev)
3146{
3147 u8 cacheline_size;
3148
3149 if (!pci_cache_line_size)
3150 return -EINVAL;
3151
3152 /* Validate current setting: the PCI_CACHE_LINE_SIZE must be
3153 equal to or multiple of the right value. */
3154 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
3155 if (cacheline_size >= pci_cache_line_size &&
3156 (cacheline_size % pci_cache_line_size) == 0)
3157 return 0;
3158
3159 /* Write the correct value. */
3160 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
3161 /* Read it back. */
3162 pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
3163 if (cacheline_size == pci_cache_line_size)
3164 return 0;
3165
3166 dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not supported\n",
3167 pci_cache_line_size << 2);
3168
3169 return -EINVAL;
3170}
3171EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
3172
3173/**
3174 * pci_set_mwi - enables memory-write-invalidate PCI transaction
3175 * @dev: the PCI device for which MWI is enabled
3176 *
3177 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
3178 *
3179 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
3180 */
3181int pci_set_mwi(struct pci_dev *dev)
3182{
3183#ifdef PCI_DISABLE_MWI
3184 return 0;
3185#else
3186 int rc;
3187 u16 cmd;
3188
3189 rc = pci_set_cacheline_size(dev);
3190 if (rc)
3191 return rc;
3192
3193 pci_read_config_word(dev, PCI_COMMAND, &cmd);
3194 if (!(cmd & PCI_COMMAND_INVALIDATE)) {
3195 dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
3196 cmd |= PCI_COMMAND_INVALIDATE;
3197 pci_write_config_word(dev, PCI_COMMAND, cmd);
3198 }
3199 return 0;
3200#endif
3201}
3202EXPORT_SYMBOL(pci_set_mwi);
3203
3204/**
3205 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
3206 * @dev: the PCI device for which MWI is enabled
3207 *
3208 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
3209 * Callers are not required to check the return value.
3210 *
3211 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
3212 */
3213int pci_try_set_mwi(struct pci_dev *dev)
3214{
3215#ifdef PCI_DISABLE_MWI
3216 return 0;
3217#else
3218 return pci_set_mwi(dev);
3219#endif
3220}
3221EXPORT_SYMBOL(pci_try_set_mwi);
3222
3223/**
3224 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
3225 * @dev: the PCI device to disable
3226 *
3227 * Disables PCI Memory-Write-Invalidate transaction on the device
3228 */
3229void pci_clear_mwi(struct pci_dev *dev)
3230{
3231#ifndef PCI_DISABLE_MWI
3232 u16 cmd;
3233
3234 pci_read_config_word(dev, PCI_COMMAND, &cmd);
3235 if (cmd & PCI_COMMAND_INVALIDATE) {
3236 cmd &= ~PCI_COMMAND_INVALIDATE;
3237 pci_write_config_word(dev, PCI_COMMAND, cmd);
3238 }
3239#endif
3240}
3241EXPORT_SYMBOL(pci_clear_mwi);
3242
3243/**
3244 * pci_intx - enables/disables PCI INTx for device dev
3245 * @pdev: the PCI device to operate on
3246 * @enable: boolean: whether to enable or disable PCI INTx
3247 *
3248 * Enables/disables PCI INTx for device dev
3249 */
3250void pci_intx(struct pci_dev *pdev, int enable)
3251{
3252 u16 pci_command, new;
3253
3254 pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
3255
3256 if (enable)
3257 new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
3258 else
3259 new = pci_command | PCI_COMMAND_INTX_DISABLE;
3260
3261 if (new != pci_command) {
3262 struct pci_devres *dr;
3263
3264 pci_write_config_word(pdev, PCI_COMMAND, new);
3265
3266 dr = find_pci_dr(pdev);
3267 if (dr && !dr->restore_intx) {
3268 dr->restore_intx = 1;
3269 dr->orig_intx = !enable;
3270 }
3271 }
3272}
3273EXPORT_SYMBOL_GPL(pci_intx);
3274
3275/**
3276 * pci_intx_mask_supported - probe for INTx masking support
3277 * @dev: the PCI device to operate on
3278 *
3279 * Check if the device dev support INTx masking via the config space
3280 * command word.
3281 */
3282bool pci_intx_mask_supported(struct pci_dev *dev)
3283{
3284 bool mask_supported = false;
3285 u16 orig, new;
3286
3287 if (dev->broken_intx_masking)
3288 return false;
3289
3290 pci_cfg_access_lock(dev);
3291
3292 pci_read_config_word(dev, PCI_COMMAND, &orig);
3293 pci_write_config_word(dev, PCI_COMMAND,
3294 orig ^ PCI_COMMAND_INTX_DISABLE);
3295 pci_read_config_word(dev, PCI_COMMAND, &new);
3296
3297 /*
3298 * There's no way to protect against hardware bugs or detect them
3299 * reliably, but as long as we know what the value should be, let's
3300 * go ahead and check it.
3301 */
3302 if ((new ^ orig) & ~PCI_COMMAND_INTX_DISABLE) {
3303 dev_err(&dev->dev, "Command register changed from 0x%x to 0x%x: driver or hardware bug?\n",
3304 orig, new);
3305 } else if ((new ^ orig) & PCI_COMMAND_INTX_DISABLE) {
3306 mask_supported = true;
3307 pci_write_config_word(dev, PCI_COMMAND, orig);
3308 }
3309
3310 pci_cfg_access_unlock(dev);
3311 return mask_supported;
3312}
3313EXPORT_SYMBOL_GPL(pci_intx_mask_supported);
3314
3315static bool pci_check_and_set_intx_mask(struct pci_dev *dev, bool mask)
3316{
3317 struct pci_bus *bus = dev->bus;
3318 bool mask_updated = true;
3319 u32 cmd_status_dword;
3320 u16 origcmd, newcmd;
3321 unsigned long flags;
3322 bool irq_pending;
3323
3324 /*
3325 * We do a single dword read to retrieve both command and status.
3326 * Document assumptions that make this possible.
3327 */
3328 BUILD_BUG_ON(PCI_COMMAND % 4);
3329 BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
3330
3331 raw_spin_lock_irqsave(&pci_lock, flags);
3332
3333 bus->ops->read(bus, dev->devfn, PCI_COMMAND, 4, &cmd_status_dword);
3334
3335 irq_pending = (cmd_status_dword >> 16) & PCI_STATUS_INTERRUPT;
3336
3337 /*
3338 * Check interrupt status register to see whether our device
3339 * triggered the interrupt (when masking) or the next IRQ is
3340 * already pending (when unmasking).
3341 */
3342 if (mask != irq_pending) {
3343 mask_updated = false;
3344 goto done;
3345 }
3346
3347 origcmd = cmd_status_dword;
3348 newcmd = origcmd & ~PCI_COMMAND_INTX_DISABLE;
3349 if (mask)
3350 newcmd |= PCI_COMMAND_INTX_DISABLE;
3351 if (newcmd != origcmd)
3352 bus->ops->write(bus, dev->devfn, PCI_COMMAND, 2, newcmd);
3353
3354done:
3355 raw_spin_unlock_irqrestore(&pci_lock, flags);
3356
3357 return mask_updated;
3358}
3359
3360/**
3361 * pci_check_and_mask_intx - mask INTx on pending interrupt
3362 * @dev: the PCI device to operate on
3363 *
3364 * Check if the device dev has its INTx line asserted, mask it and
3365 * return true in that case. False is returned if not interrupt was
3366 * pending.
3367 */
3368bool pci_check_and_mask_intx(struct pci_dev *dev)
3369{
3370 return pci_check_and_set_intx_mask(dev, true);
3371}
3372EXPORT_SYMBOL_GPL(pci_check_and_mask_intx);
3373
3374/**
3375 * pci_check_and_unmask_intx - unmask INTx if no interrupt is pending
3376 * @dev: the PCI device to operate on
3377 *
3378 * Check if the device dev has its INTx line asserted, unmask it if not
3379 * and return true. False is returned and the mask remains active if
3380 * there was still an interrupt pending.
3381 */
3382bool pci_check_and_unmask_intx(struct pci_dev *dev)
3383{
3384 return pci_check_and_set_intx_mask(dev, false);
3385}
3386EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx);
3387
3388/**
3389 * pci_wait_for_pending_transaction - waits for pending transaction
3390 * @dev: the PCI device to operate on
3391 *
3392 * Return 0 if transaction is pending 1 otherwise.
3393 */
3394int pci_wait_for_pending_transaction(struct pci_dev *dev)
3395{
3396 if (!pci_is_pcie(dev))
3397 return 1;
3398
3399 return pci_wait_for_pending(dev, pci_pcie_cap(dev) + PCI_EXP_DEVSTA,
3400 PCI_EXP_DEVSTA_TRPND);
3401}
3402EXPORT_SYMBOL(pci_wait_for_pending_transaction);
3403
3404/*
3405 * We should only need to wait 100ms after FLR, but some devices take longer.
3406 * Wait for up to 1000ms for config space to return something other than -1.
3407 * Intel IGD requires this when an LCD panel is attached. We read the 2nd
3408 * dword because VFs don't implement the 1st dword.
3409 */
3410static void pci_flr_wait(struct pci_dev *dev)
3411{
3412 int i = 0;
3413 u32 id;
3414
3415 do {
3416 msleep(100);
3417 pci_read_config_dword(dev, PCI_COMMAND, &id);
3418 } while (i++ < 10 && id == ~0);
3419
3420 if (id == ~0)
3421 dev_warn(&dev->dev, "Failed to return from FLR\n");
3422 else if (i > 1)
3423 dev_info(&dev->dev, "Required additional %dms to return from FLR\n",
3424 (i - 1) * 100);
3425}
3426
3427static int pcie_flr(struct pci_dev *dev, int probe)
3428{
3429 u32 cap;
3430
3431 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
3432 if (!(cap & PCI_EXP_DEVCAP_FLR))
3433 return -ENOTTY;
3434
3435 if (probe)
3436 return 0;
3437
3438 if (!pci_wait_for_pending_transaction(dev))
3439 dev_err(&dev->dev, "timed out waiting for pending transaction; performing function level reset anyway\n");
3440
3441 pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR);
3442 pci_flr_wait(dev);
3443 return 0;
3444}
3445
3446static int pci_af_flr(struct pci_dev *dev, int probe)
3447{
3448 int pos;
3449 u8 cap;
3450
3451 pos = pci_find_capability(dev, PCI_CAP_ID_AF);
3452 if (!pos)
3453 return -ENOTTY;
3454
3455 pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
3456 if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
3457 return -ENOTTY;
3458
3459 if (probe)
3460 return 0;
3461
3462 /*
3463 * Wait for Transaction Pending bit to clear. A word-aligned test
3464 * is used, so we use the conrol offset rather than status and shift
3465 * the test bit to match.
3466 */
3467 if (!pci_wait_for_pending(dev, pos + PCI_AF_CTRL,
3468 PCI_AF_STATUS_TP << 8))
3469 dev_err(&dev->dev, "timed out waiting for pending transaction; performing AF function level reset anyway\n");
3470
3471 pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
3472 pci_flr_wait(dev);
3473 return 0;
3474}
3475
3476/**
3477 * pci_pm_reset - Put device into PCI_D3 and back into PCI_D0.
3478 * @dev: Device to reset.
3479 * @probe: If set, only check if the device can be reset this way.
3480 *
3481 * If @dev supports native PCI PM and its PCI_PM_CTRL_NO_SOFT_RESET flag is
3482 * unset, it will be reinitialized internally when going from PCI_D3hot to
3483 * PCI_D0. If that's the case and the device is not in a low-power state
3484 * already, force it into PCI_D3hot and back to PCI_D0, causing it to be reset.
3485 *
3486 * NOTE: This causes the caller to sleep for twice the device power transition
3487 * cooldown period, which for the D0->D3hot and D3hot->D0 transitions is 10 ms
3488 * by default (i.e. unless the @dev's d3_delay field has a different value).
3489 * Moreover, only devices in D0 can be reset by this function.
3490 */
3491static int pci_pm_reset(struct pci_dev *dev, int probe)
3492{
3493 u16 csr;
3494
3495 if (!dev->pm_cap || dev->dev_flags & PCI_DEV_FLAGS_NO_PM_RESET)
3496 return -ENOTTY;
3497
3498 pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
3499 if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
3500 return -ENOTTY;
3501
3502 if (probe)
3503 return 0;
3504
3505 if (dev->current_state != PCI_D0)
3506 return -EINVAL;
3507
3508 csr &= ~PCI_PM_CTRL_STATE_MASK;
3509 csr |= PCI_D3hot;
3510 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
3511 pci_dev_d3_sleep(dev);
3512
3513 csr &= ~PCI_PM_CTRL_STATE_MASK;
3514 csr |= PCI_D0;
3515 pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
3516 pci_dev_d3_sleep(dev);
3517
3518 return 0;
3519}
3520
3521void pci_reset_secondary_bus(struct pci_dev *dev)
3522{
3523 u16 ctrl;
3524
3525 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &ctrl);
3526 ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
3527 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
3528 /*
3529 * PCI spec v3.0 7.6.4.2 requires minimum Trst of 1ms. Double
3530 * this to 2ms to ensure that we meet the minimum requirement.
3531 */
3532 msleep(2);
3533
3534 ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
3535 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl);
3536
3537 /*
3538 * Trhfa for conventional PCI is 2^25 clock cycles.
3539 * Assuming a minimum 33MHz clock this results in a 1s
3540 * delay before we can consider subordinate devices to
3541 * be re-initialized. PCIe has some ways to shorten this,
3542 * but we don't make use of them yet.
3543 */
3544 ssleep(1);
3545}
3546
3547void __weak pcibios_reset_secondary_bus(struct pci_dev *dev)
3548{
3549 pci_reset_secondary_bus(dev);
3550}
3551
3552/**
3553 * pci_reset_bridge_secondary_bus - Reset the secondary bus on a PCI bridge.
3554 * @dev: Bridge device
3555 *
3556 * Use the bridge control register to assert reset on the secondary bus.
3557 * Devices on the secondary bus are left in power-on state.
3558 */
3559void pci_reset_bridge_secondary_bus(struct pci_dev *dev)
3560{
3561 pcibios_reset_secondary_bus(dev);
3562}
3563EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus);
3564
3565static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
3566{
3567 struct pci_dev *pdev;
3568
3569 if (pci_is_root_bus(dev->bus) || dev->subordinate ||
3570 !dev->bus->self || dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
3571 return -ENOTTY;
3572
3573 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
3574 if (pdev != dev)
3575 return -ENOTTY;
3576
3577 if (probe)
3578 return 0;
3579
3580 pci_reset_bridge_secondary_bus(dev->bus->self);
3581
3582 return 0;
3583}
3584
3585static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe)
3586{
3587 int rc = -ENOTTY;
3588
3589 if (!hotplug || !try_module_get(hotplug->ops->owner))
3590 return rc;
3591
3592 if (hotplug->ops->reset_slot)
3593 rc = hotplug->ops->reset_slot(hotplug, probe);
3594
3595 module_put(hotplug->ops->owner);
3596
3597 return rc;
3598}
3599
3600static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe)
3601{
3602 struct pci_dev *pdev;
3603
3604 if (dev->subordinate || !dev->slot ||
3605 dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
3606 return -ENOTTY;
3607
3608 list_for_each_entry(pdev, &dev->bus->devices, bus_list)
3609 if (pdev != dev && pdev->slot == dev->slot)
3610 return -ENOTTY;
3611
3612 return pci_reset_hotplug_slot(dev->slot->hotplug, probe);
3613}
3614
3615static int __pci_dev_reset(struct pci_dev *dev, int probe)
3616{
3617 int rc;
3618
3619 might_sleep();
3620
3621 rc = pci_dev_specific_reset(dev, probe);
3622 if (rc != -ENOTTY)
3623 goto done;
3624
3625 rc = pcie_flr(dev, probe);
3626 if (rc != -ENOTTY)
3627 goto done;
3628
3629 rc = pci_af_flr(dev, probe);
3630 if (rc != -ENOTTY)
3631 goto done;
3632
3633 rc = pci_pm_reset(dev, probe);
3634 if (rc != -ENOTTY)
3635 goto done;
3636
3637 rc = pci_dev_reset_slot_function(dev, probe);
3638 if (rc != -ENOTTY)
3639 goto done;
3640
3641 rc = pci_parent_bus_reset(dev, probe);
3642done:
3643 return rc;
3644}
3645
3646static void pci_dev_lock(struct pci_dev *dev)
3647{
3648 pci_cfg_access_lock(dev);
3649 /* block PM suspend, driver probe, etc. */
3650 device_lock(&dev->dev);
3651}
3652
3653/* Return 1 on successful lock, 0 on contention */
3654static int pci_dev_trylock(struct pci_dev *dev)
3655{
3656 if (pci_cfg_access_trylock(dev)) {
3657 if (device_trylock(&dev->dev))
3658 return 1;
3659 pci_cfg_access_unlock(dev);
3660 }
3661
3662 return 0;
3663}
3664
3665static void pci_dev_unlock(struct pci_dev *dev)
3666{
3667 device_unlock(&dev->dev);
3668 pci_cfg_access_unlock(dev);
3669}
3670
3671/**
3672 * pci_reset_notify - notify device driver of reset
3673 * @dev: device to be notified of reset
3674 * @prepare: 'true' if device is about to be reset; 'false' if reset attempt
3675 * completed
3676 *
3677 * Must be called prior to device access being disabled and after device
3678 * access is restored.
3679 */
3680static void pci_reset_notify(struct pci_dev *dev, bool prepare)
3681{
3682 const struct pci_error_handlers *err_handler =
3683 dev->driver ? dev->driver->err_handler : NULL;
3684 if (err_handler && err_handler->reset_notify)
3685 err_handler->reset_notify(dev, prepare);
3686}
3687
3688static void pci_dev_save_and_disable(struct pci_dev *dev)
3689{
3690 pci_reset_notify(dev, true);
3691
3692 /*
3693 * Wake-up device prior to save. PM registers default to D0 after
3694 * reset and a simple register restore doesn't reliably return
3695 * to a non-D0 state anyway.
3696 */
3697 pci_set_power_state(dev, PCI_D0);
3698
3699 pci_save_state(dev);
3700 /*
3701 * Disable the device by clearing the Command register, except for
3702 * INTx-disable which is set. This not only disables MMIO and I/O port
3703 * BARs, but also prevents the device from being Bus Master, preventing
3704 * DMA from the device including MSI/MSI-X interrupts. For PCI 2.3
3705 * compliant devices, INTx-disable prevents legacy interrupts.
3706 */
3707 pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
3708}
3709
3710static void pci_dev_restore(struct pci_dev *dev)
3711{
3712 pci_restore_state(dev);
3713 pci_reset_notify(dev, false);
3714}
3715
3716static int pci_dev_reset(struct pci_dev *dev, int probe)
3717{
3718 int rc;
3719
3720 if (!probe)
3721 pci_dev_lock(dev);
3722
3723 rc = __pci_dev_reset(dev, probe);
3724
3725 if (!probe)
3726 pci_dev_unlock(dev);
3727
3728 return rc;
3729}
3730
3731/**
3732 * __pci_reset_function - reset a PCI device function
3733 * @dev: PCI device to reset
3734 *
3735 * Some devices allow an individual function to be reset without affecting
3736 * other functions in the same device. The PCI device must be responsive
3737 * to PCI config space in order to use this function.
3738 *
3739 * The device function is presumed to be unused when this function is called.
3740 * Resetting the device will make the contents of PCI configuration space
3741 * random, so any caller of this must be prepared to reinitialise the
3742 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
3743 * etc.
3744 *
3745 * Returns 0 if the device function was successfully reset or negative if the
3746 * device doesn't support resetting a single function.
3747 */
3748int __pci_reset_function(struct pci_dev *dev)
3749{
3750 return pci_dev_reset(dev, 0);
3751}
3752EXPORT_SYMBOL_GPL(__pci_reset_function);
3753
3754/**
3755 * __pci_reset_function_locked - reset a PCI device function while holding
3756 * the @dev mutex lock.
3757 * @dev: PCI device to reset
3758 *
3759 * Some devices allow an individual function to be reset without affecting
3760 * other functions in the same device. The PCI device must be responsive
3761 * to PCI config space in order to use this function.
3762 *
3763 * The device function is presumed to be unused and the caller is holding
3764 * the device mutex lock when this function is called.
3765 * Resetting the device will make the contents of PCI configuration space
3766 * random, so any caller of this must be prepared to reinitialise the
3767 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
3768 * etc.
3769 *
3770 * Returns 0 if the device function was successfully reset or negative if the
3771 * device doesn't support resetting a single function.
3772 */
3773int __pci_reset_function_locked(struct pci_dev *dev)
3774{
3775 return __pci_dev_reset(dev, 0);
3776}
3777EXPORT_SYMBOL_GPL(__pci_reset_function_locked);
3778
3779/**
3780 * pci_probe_reset_function - check whether the device can be safely reset
3781 * @dev: PCI device to reset
3782 *
3783 * Some devices allow an individual function to be reset without affecting
3784 * other functions in the same device. The PCI device must be responsive
3785 * to PCI config space in order to use this function.
3786 *
3787 * Returns 0 if the device function can be reset or negative if the
3788 * device doesn't support resetting a single function.
3789 */
3790int pci_probe_reset_function(struct pci_dev *dev)
3791{
3792 return pci_dev_reset(dev, 1);
3793}
3794
3795/**
3796 * pci_reset_function - quiesce and reset a PCI device function
3797 * @dev: PCI device to reset
3798 *
3799 * Some devices allow an individual function to be reset without affecting
3800 * other functions in the same device. The PCI device must be responsive
3801 * to PCI config space in order to use this function.
3802 *
3803 * This function does not just reset the PCI portion of a device, but
3804 * clears all the state associated with the device. This function differs
3805 * from __pci_reset_function in that it saves and restores device state
3806 * over the reset.
3807 *
3808 * Returns 0 if the device function was successfully reset or negative if the
3809 * device doesn't support resetting a single function.
3810 */
3811int pci_reset_function(struct pci_dev *dev)
3812{
3813 int rc;
3814
3815 rc = pci_dev_reset(dev, 1);
3816 if (rc)
3817 return rc;
3818
3819 pci_dev_save_and_disable(dev);
3820
3821 rc = pci_dev_reset(dev, 0);
3822
3823 pci_dev_restore(dev);
3824
3825 return rc;
3826}
3827EXPORT_SYMBOL_GPL(pci_reset_function);
3828
3829/**
3830 * pci_try_reset_function - quiesce and reset a PCI device function
3831 * @dev: PCI device to reset
3832 *
3833 * Same as above, except return -EAGAIN if unable to lock device.
3834 */
3835int pci_try_reset_function(struct pci_dev *dev)
3836{
3837 int rc;
3838
3839 rc = pci_dev_reset(dev, 1);
3840 if (rc)
3841 return rc;
3842
3843 pci_dev_save_and_disable(dev);
3844
3845 if (pci_dev_trylock(dev)) {
3846 rc = __pci_dev_reset(dev, 0);
3847 pci_dev_unlock(dev);
3848 } else
3849 rc = -EAGAIN;
3850
3851 pci_dev_restore(dev);
3852
3853 return rc;
3854}
3855EXPORT_SYMBOL_GPL(pci_try_reset_function);
3856
3857/* Do any devices on or below this bus prevent a bus reset? */
3858static bool pci_bus_resetable(struct pci_bus *bus)
3859{
3860 struct pci_dev *dev;
3861
3862 list_for_each_entry(dev, &bus->devices, bus_list) {
3863 if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
3864 (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
3865 return false;
3866 }
3867
3868 return true;
3869}
3870
3871/* Lock devices from the top of the tree down */
3872static void pci_bus_lock(struct pci_bus *bus)
3873{
3874 struct pci_dev *dev;
3875
3876 list_for_each_entry(dev, &bus->devices, bus_list) {
3877 pci_dev_lock(dev);
3878 if (dev->subordinate)
3879 pci_bus_lock(dev->subordinate);
3880 }
3881}
3882
3883/* Unlock devices from the bottom of the tree up */
3884static void pci_bus_unlock(struct pci_bus *bus)
3885{
3886 struct pci_dev *dev;
3887
3888 list_for_each_entry(dev, &bus->devices, bus_list) {
3889 if (dev->subordinate)
3890 pci_bus_unlock(dev->subordinate);
3891 pci_dev_unlock(dev);
3892 }
3893}
3894
3895/* Return 1 on successful lock, 0 on contention */
3896static int pci_bus_trylock(struct pci_bus *bus)
3897{
3898 struct pci_dev *dev;
3899
3900 list_for_each_entry(dev, &bus->devices, bus_list) {
3901 if (!pci_dev_trylock(dev))
3902 goto unlock;
3903 if (dev->subordinate) {
3904 if (!pci_bus_trylock(dev->subordinate)) {
3905 pci_dev_unlock(dev);
3906 goto unlock;
3907 }
3908 }
3909 }
3910 return 1;
3911
3912unlock:
3913 list_for_each_entry_continue_reverse(dev, &bus->devices, bus_list) {
3914 if (dev->subordinate)
3915 pci_bus_unlock(dev->subordinate);
3916 pci_dev_unlock(dev);
3917 }
3918 return 0;
3919}
3920
3921/* Do any devices on or below this slot prevent a bus reset? */
3922static bool pci_slot_resetable(struct pci_slot *slot)
3923{
3924 struct pci_dev *dev;
3925
3926 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3927 if (!dev->slot || dev->slot != slot)
3928 continue;
3929 if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
3930 (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
3931 return false;
3932 }
3933
3934 return true;
3935}
3936
3937/* Lock devices from the top of the tree down */
3938static void pci_slot_lock(struct pci_slot *slot)
3939{
3940 struct pci_dev *dev;
3941
3942 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3943 if (!dev->slot || dev->slot != slot)
3944 continue;
3945 pci_dev_lock(dev);
3946 if (dev->subordinate)
3947 pci_bus_lock(dev->subordinate);
3948 }
3949}
3950
3951/* Unlock devices from the bottom of the tree up */
3952static void pci_slot_unlock(struct pci_slot *slot)
3953{
3954 struct pci_dev *dev;
3955
3956 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3957 if (!dev->slot || dev->slot != slot)
3958 continue;
3959 if (dev->subordinate)
3960 pci_bus_unlock(dev->subordinate);
3961 pci_dev_unlock(dev);
3962 }
3963}
3964
3965/* Return 1 on successful lock, 0 on contention */
3966static int pci_slot_trylock(struct pci_slot *slot)
3967{
3968 struct pci_dev *dev;
3969
3970 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
3971 if (!dev->slot || dev->slot != slot)
3972 continue;
3973 if (!pci_dev_trylock(dev))
3974 goto unlock;
3975 if (dev->subordinate) {
3976 if (!pci_bus_trylock(dev->subordinate)) {
3977 pci_dev_unlock(dev);
3978 goto unlock;
3979 }
3980 }
3981 }
3982 return 1;
3983
3984unlock:
3985 list_for_each_entry_continue_reverse(dev,
3986 &slot->bus->devices, bus_list) {
3987 if (!dev->slot || dev->slot != slot)
3988 continue;
3989 if (dev->subordinate)
3990 pci_bus_unlock(dev->subordinate);
3991 pci_dev_unlock(dev);
3992 }
3993 return 0;
3994}
3995
3996/* Save and disable devices from the top of the tree down */
3997static void pci_bus_save_and_disable(struct pci_bus *bus)
3998{
3999 struct pci_dev *dev;
4000
4001 list_for_each_entry(dev, &bus->devices, bus_list) {
4002 pci_dev_save_and_disable(dev);
4003 if (dev->subordinate)
4004 pci_bus_save_and_disable(dev->subordinate);
4005 }
4006}
4007
4008/*
4009 * Restore devices from top of the tree down - parent bridges need to be
4010 * restored before we can get to subordinate devices.
4011 */
4012static void pci_bus_restore(struct pci_bus *bus)
4013{
4014 struct pci_dev *dev;
4015
4016 list_for_each_entry(dev, &bus->devices, bus_list) {
4017 pci_dev_restore(dev);
4018 if (dev->subordinate)
4019 pci_bus_restore(dev->subordinate);
4020 }
4021}
4022
4023/* Save and disable devices from the top of the tree down */
4024static void pci_slot_save_and_disable(struct pci_slot *slot)
4025{
4026 struct pci_dev *dev;
4027
4028 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
4029 if (!dev->slot || dev->slot != slot)
4030 continue;
4031 pci_dev_save_and_disable(dev);
4032 if (dev->subordinate)
4033 pci_bus_save_and_disable(dev->subordinate);
4034 }
4035}
4036
4037/*
4038 * Restore devices from top of the tree down - parent bridges need to be
4039 * restored before we can get to subordinate devices.
4040 */
4041static void pci_slot_restore(struct pci_slot *slot)
4042{
4043 struct pci_dev *dev;
4044
4045 list_for_each_entry(dev, &slot->bus->devices, bus_list) {
4046 if (!dev->slot || dev->slot != slot)
4047 continue;
4048 pci_dev_restore(dev);
4049 if (dev->subordinate)
4050 pci_bus_restore(dev->subordinate);
4051 }
4052}
4053
4054static int pci_slot_reset(struct pci_slot *slot, int probe)
4055{
4056 int rc;
4057
4058 if (!slot || !pci_slot_resetable(slot))
4059 return -ENOTTY;
4060
4061 if (!probe)
4062 pci_slot_lock(slot);
4063
4064 might_sleep();
4065
4066 rc = pci_reset_hotplug_slot(slot->hotplug, probe);
4067
4068 if (!probe)
4069 pci_slot_unlock(slot);
4070
4071 return rc;
4072}
4073
4074/**
4075 * pci_probe_reset_slot - probe whether a PCI slot can be reset
4076 * @slot: PCI slot to probe
4077 *
4078 * Return 0 if slot can be reset, negative if a slot reset is not supported.
4079 */
4080int pci_probe_reset_slot(struct pci_slot *slot)
4081{
4082 return pci_slot_reset(slot, 1);
4083}
4084EXPORT_SYMBOL_GPL(pci_probe_reset_slot);
4085
4086/**
4087 * pci_reset_slot - reset a PCI slot
4088 * @slot: PCI slot to reset
4089 *
4090 * A PCI bus may host multiple slots, each slot may support a reset mechanism
4091 * independent of other slots. For instance, some slots may support slot power
4092 * control. In the case of a 1:1 bus to slot architecture, this function may
4093 * wrap the bus reset to avoid spurious slot related events such as hotplug.
4094 * Generally a slot reset should be attempted before a bus reset. All of the
4095 * function of the slot and any subordinate buses behind the slot are reset
4096 * through this function. PCI config space of all devices in the slot and
4097 * behind the slot is saved before and restored after reset.
4098 *
4099 * Return 0 on success, non-zero on error.
4100 */
4101int pci_reset_slot(struct pci_slot *slot)
4102{
4103 int rc;
4104
4105 rc = pci_slot_reset(slot, 1);
4106 if (rc)
4107 return rc;
4108
4109 pci_slot_save_and_disable(slot);
4110
4111 rc = pci_slot_reset(slot, 0);
4112
4113 pci_slot_restore(slot);
4114
4115 return rc;
4116}
4117EXPORT_SYMBOL_GPL(pci_reset_slot);
4118
4119/**
4120 * pci_try_reset_slot - Try to reset a PCI slot
4121 * @slot: PCI slot to reset
4122 *
4123 * Same as above except return -EAGAIN if the slot cannot be locked
4124 */
4125int pci_try_reset_slot(struct pci_slot *slot)
4126{
4127 int rc;
4128
4129 rc = pci_slot_reset(slot, 1);
4130 if (rc)
4131 return rc;
4132
4133 pci_slot_save_and_disable(slot);
4134
4135 if (pci_slot_trylock(slot)) {
4136 might_sleep();
4137 rc = pci_reset_hotplug_slot(slot->hotplug, 0);
4138 pci_slot_unlock(slot);
4139 } else
4140 rc = -EAGAIN;
4141
4142 pci_slot_restore(slot);
4143
4144 return rc;
4145}
4146EXPORT_SYMBOL_GPL(pci_try_reset_slot);
4147
4148static int pci_bus_reset(struct pci_bus *bus, int probe)
4149{
4150 if (!bus->self || !pci_bus_resetable(bus))
4151 return -ENOTTY;
4152
4153 if (probe)
4154 return 0;
4155
4156 pci_bus_lock(bus);
4157
4158 might_sleep();
4159
4160 pci_reset_bridge_secondary_bus(bus->self);
4161
4162 pci_bus_unlock(bus);
4163
4164 return 0;
4165}
4166
4167/**
4168 * pci_probe_reset_bus - probe whether a PCI bus can be reset
4169 * @bus: PCI bus to probe
4170 *
4171 * Return 0 if bus can be reset, negative if a bus reset is not supported.
4172 */
4173int pci_probe_reset_bus(struct pci_bus *bus)
4174{
4175 return pci_bus_reset(bus, 1);
4176}
4177EXPORT_SYMBOL_GPL(pci_probe_reset_bus);
4178
4179/**
4180 * pci_reset_bus - reset a PCI bus
4181 * @bus: top level PCI bus to reset
4182 *
4183 * Do a bus reset on the given bus and any subordinate buses, saving
4184 * and restoring state of all devices.
4185 *
4186 * Return 0 on success, non-zero on error.
4187 */
4188int pci_reset_bus(struct pci_bus *bus)
4189{
4190 int rc;
4191
4192 rc = pci_bus_reset(bus, 1);
4193 if (rc)
4194 return rc;
4195
4196 pci_bus_save_and_disable(bus);
4197
4198 rc = pci_bus_reset(bus, 0);
4199
4200 pci_bus_restore(bus);
4201
4202 return rc;
4203}
4204EXPORT_SYMBOL_GPL(pci_reset_bus);
4205
4206/**
4207 * pci_try_reset_bus - Try to reset a PCI bus
4208 * @bus: top level PCI bus to reset
4209 *
4210 * Same as above except return -EAGAIN if the bus cannot be locked
4211 */
4212int pci_try_reset_bus(struct pci_bus *bus)
4213{
4214 int rc;
4215
4216 rc = pci_bus_reset(bus, 1);
4217 if (rc)
4218 return rc;
4219
4220 pci_bus_save_and_disable(bus);
4221
4222 if (pci_bus_trylock(bus)) {
4223 might_sleep();
4224 pci_reset_bridge_secondary_bus(bus->self);
4225 pci_bus_unlock(bus);
4226 } else
4227 rc = -EAGAIN;
4228
4229 pci_bus_restore(bus);
4230
4231 return rc;
4232}
4233EXPORT_SYMBOL_GPL(pci_try_reset_bus);
4234
4235/**
4236 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
4237 * @dev: PCI device to query
4238 *
4239 * Returns mmrbc: maximum designed memory read count in bytes
4240 * or appropriate error value.
4241 */
4242int pcix_get_max_mmrbc(struct pci_dev *dev)
4243{
4244 int cap;
4245 u32 stat;
4246
4247 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
4248 if (!cap)
4249 return -EINVAL;
4250
4251 if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
4252 return -EINVAL;
4253
4254 return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21);
4255}
4256EXPORT_SYMBOL(pcix_get_max_mmrbc);
4257
4258/**
4259 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
4260 * @dev: PCI device to query
4261 *
4262 * Returns mmrbc: maximum memory read count in bytes
4263 * or appropriate error value.
4264 */
4265int pcix_get_mmrbc(struct pci_dev *dev)
4266{
4267 int cap;
4268 u16 cmd;
4269
4270 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
4271 if (!cap)
4272 return -EINVAL;
4273
4274 if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
4275 return -EINVAL;
4276
4277 return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
4278}
4279EXPORT_SYMBOL(pcix_get_mmrbc);
4280
4281/**
4282 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
4283 * @dev: PCI device to query
4284 * @mmrbc: maximum memory read count in bytes
4285 * valid values are 512, 1024, 2048, 4096
4286 *
4287 * If possible sets maximum memory read byte count, some bridges have erratas
4288 * that prevent this.
4289 */
4290int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
4291{
4292 int cap;
4293 u32 stat, v, o;
4294 u16 cmd;
4295
4296 if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
4297 return -EINVAL;
4298
4299 v = ffs(mmrbc) - 10;
4300
4301 cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
4302 if (!cap)
4303 return -EINVAL;
4304
4305 if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
4306 return -EINVAL;
4307
4308 if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
4309 return -E2BIG;
4310
4311 if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
4312 return -EINVAL;
4313
4314 o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
4315 if (o != v) {
4316 if (v > o && (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
4317 return -EIO;
4318
4319 cmd &= ~PCI_X_CMD_MAX_READ;
4320 cmd |= v << 2;
4321 if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd))
4322 return -EIO;
4323 }
4324 return 0;
4325}
4326EXPORT_SYMBOL(pcix_set_mmrbc);
4327
4328/**
4329 * pcie_get_readrq - get PCI Express read request size
4330 * @dev: PCI device to query
4331 *
4332 * Returns maximum memory read request in bytes
4333 * or appropriate error value.
4334 */
4335int pcie_get_readrq(struct pci_dev *dev)
4336{
4337 u16 ctl;
4338
4339 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
4340
4341 return 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
4342}
4343EXPORT_SYMBOL(pcie_get_readrq);
4344
4345/**
4346 * pcie_set_readrq - set PCI Express maximum memory read request
4347 * @dev: PCI device to query
4348 * @rq: maximum memory read count in bytes
4349 * valid values are 128, 256, 512, 1024, 2048, 4096
4350 *
4351 * If possible sets maximum memory read request in bytes
4352 */
4353int pcie_set_readrq(struct pci_dev *dev, int rq)
4354{
4355 u16 v;
4356
4357 if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
4358 return -EINVAL;
4359
4360 /*
4361 * If using the "performance" PCIe config, we clamp the
4362 * read rq size to the max packet size to prevent the
4363 * host bridge generating requests larger than we can
4364 * cope with
4365 */
4366 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
4367 int mps = pcie_get_mps(dev);
4368
4369 if (mps < rq)
4370 rq = mps;
4371 }
4372
4373 v = (ffs(rq) - 8) << 12;
4374
4375 return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
4376 PCI_EXP_DEVCTL_READRQ, v);
4377}
4378EXPORT_SYMBOL(pcie_set_readrq);
4379
4380/**
4381 * pcie_get_mps - get PCI Express maximum payload size
4382 * @dev: PCI device to query
4383 *
4384 * Returns maximum payload size in bytes
4385 */
4386int pcie_get_mps(struct pci_dev *dev)
4387{
4388 u16 ctl;
4389
4390 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
4391
4392 return 128 << ((ctl & PCI_EXP_DEVCTL_PAYLOAD) >> 5);
4393}
4394EXPORT_SYMBOL(pcie_get_mps);
4395
4396/**
4397 * pcie_set_mps - set PCI Express maximum payload size
4398 * @dev: PCI device to query
4399 * @mps: maximum payload size in bytes
4400 * valid values are 128, 256, 512, 1024, 2048, 4096
4401 *
4402 * If possible sets maximum payload size
4403 */
4404int pcie_set_mps(struct pci_dev *dev, int mps)
4405{
4406 u16 v;
4407
4408 if (mps < 128 || mps > 4096 || !is_power_of_2(mps))
4409 return -EINVAL;
4410
4411 v = ffs(mps) - 8;
4412 if (v > dev->pcie_mpss)
4413 return -EINVAL;
4414 v <<= 5;
4415
4416 return pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
4417 PCI_EXP_DEVCTL_PAYLOAD, v);
4418}
4419EXPORT_SYMBOL(pcie_set_mps);
4420
4421/**
4422 * pcie_get_minimum_link - determine minimum link settings of a PCI device
4423 * @dev: PCI device to query
4424 * @speed: storage for minimum speed
4425 * @width: storage for minimum width
4426 *
4427 * This function will walk up the PCI device chain and determine the minimum
4428 * link width and speed of the device.
4429 */
4430int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed,
4431 enum pcie_link_width *width)
4432{
4433 int ret;
4434
4435 *speed = PCI_SPEED_UNKNOWN;
4436 *width = PCIE_LNK_WIDTH_UNKNOWN;
4437
4438 while (dev) {
4439 u16 lnksta;
4440 enum pci_bus_speed next_speed;
4441 enum pcie_link_width next_width;
4442
4443 ret = pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);
4444 if (ret)
4445 return ret;
4446
4447 next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
4448 next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >>
4449 PCI_EXP_LNKSTA_NLW_SHIFT;
4450
4451 if (next_speed < *speed)
4452 *speed = next_speed;
4453
4454 if (next_width < *width)
4455 *width = next_width;
4456
4457 dev = dev->bus->self;
4458 }
4459
4460 return 0;
4461}
4462EXPORT_SYMBOL(pcie_get_minimum_link);
4463
4464/**
4465 * pci_select_bars - Make BAR mask from the type of resource
4466 * @dev: the PCI device for which BAR mask is made
4467 * @flags: resource type mask to be selected
4468 *
4469 * This helper routine makes bar mask from the type of resource.
4470 */
4471int pci_select_bars(struct pci_dev *dev, unsigned long flags)
4472{
4473 int i, bars = 0;
4474 for (i = 0; i < PCI_NUM_RESOURCES; i++)
4475 if (pci_resource_flags(dev, i) & flags)
4476 bars |= (1 << i);
4477 return bars;
4478}
4479EXPORT_SYMBOL(pci_select_bars);
4480
4481/**
4482 * pci_resource_bar - get position of the BAR associated with a resource
4483 * @dev: the PCI device
4484 * @resno: the resource number
4485 * @type: the BAR type to be filled in
4486 *
4487 * Returns BAR position in config space, or 0 if the BAR is invalid.
4488 */
4489int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type)
4490{
4491 int reg;
4492
4493 if (resno < PCI_ROM_RESOURCE) {
4494 *type = pci_bar_unknown;
4495 return PCI_BASE_ADDRESS_0 + 4 * resno;
4496 } else if (resno == PCI_ROM_RESOURCE) {
4497 *type = pci_bar_mem32;
4498 return dev->rom_base_reg;
4499 } else if (resno < PCI_BRIDGE_RESOURCES) {
4500 /* device specific resource */
4501 *type = pci_bar_unknown;
4502 reg = pci_iov_resource_bar(dev, resno);
4503 if (reg)
4504 return reg;
4505 }
4506
4507 dev_err(&dev->dev, "BAR %d: invalid resource\n", resno);
4508 return 0;
4509}
4510
4511/* Some architectures require additional programming to enable VGA */
4512static arch_set_vga_state_t arch_set_vga_state;
4513
4514void __init pci_register_set_vga_state(arch_set_vga_state_t func)
4515{
4516 arch_set_vga_state = func; /* NULL disables */
4517}
4518
4519static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode,
4520 unsigned int command_bits, u32 flags)
4521{
4522 if (arch_set_vga_state)
4523 return arch_set_vga_state(dev, decode, command_bits,
4524 flags);
4525 return 0;
4526}
4527
4528/**
4529 * pci_set_vga_state - set VGA decode state on device and parents if requested
4530 * @dev: the PCI device
4531 * @decode: true = enable decoding, false = disable decoding
4532 * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
4533 * @flags: traverse ancestors and change bridges
4534 * CHANGE_BRIDGE_ONLY / CHANGE_BRIDGE
4535 */
4536int pci_set_vga_state(struct pci_dev *dev, bool decode,
4537 unsigned int command_bits, u32 flags)
4538{
4539 struct pci_bus *bus;
4540 struct pci_dev *bridge;
4541 u16 cmd;
4542 int rc;
4543
4544 WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) && (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY)));
4545
4546 /* ARCH specific VGA enables */
4547 rc = pci_set_vga_state_arch(dev, decode, command_bits, flags);
4548 if (rc)
4549 return rc;
4550
4551 if (flags & PCI_VGA_STATE_CHANGE_DECODES) {
4552 pci_read_config_word(dev, PCI_COMMAND, &cmd);
4553 if (decode == true)
4554 cmd |= command_bits;
4555 else
4556 cmd &= ~command_bits;
4557 pci_write_config_word(dev, PCI_COMMAND, cmd);
4558 }
4559
4560 if (!(flags & PCI_VGA_STATE_CHANGE_BRIDGE))
4561 return 0;
4562
4563 bus = dev->bus;
4564 while (bus) {
4565 bridge = bus->self;
4566 if (bridge) {
4567 pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
4568 &cmd);
4569 if (decode == true)
4570 cmd |= PCI_BRIDGE_CTL_VGA;
4571 else
4572 cmd &= ~PCI_BRIDGE_CTL_VGA;
4573 pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
4574 cmd);
4575 }
4576 bus = bus->parent;
4577 }
4578 return 0;
4579}
4580
4581bool pci_device_is_present(struct pci_dev *pdev)
4582{
4583 u32 v;
4584
4585 return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0);
4586}
4587EXPORT_SYMBOL_GPL(pci_device_is_present);
4588
4589void pci_ignore_hotplug(struct pci_dev *dev)
4590{
4591 struct pci_dev *bridge = dev->bus->self;
4592
4593 dev->ignore_hotplug = 1;
4594 /* Propagate the "ignore hotplug" setting to the parent bridge. */
4595 if (bridge)
4596 bridge->ignore_hotplug = 1;
4597}
4598EXPORT_SYMBOL_GPL(pci_ignore_hotplug);
4599
4600#define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
4601static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
4602static DEFINE_SPINLOCK(resource_alignment_lock);
4603
4604/**
4605 * pci_specified_resource_alignment - get resource alignment specified by user.
4606 * @dev: the PCI device to get
4607 *
4608 * RETURNS: Resource alignment if it is specified.
4609 * Zero if it is not specified.
4610 */
4611static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
4612{
4613 int seg, bus, slot, func, align_order, count;
4614 resource_size_t align = 0;
4615 char *p;
4616
4617 spin_lock(&resource_alignment_lock);
4618 p = resource_alignment_param;
4619 while (*p) {
4620 count = 0;
4621 if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
4622 p[count] == '@') {
4623 p += count + 1;
4624 } else {
4625 align_order = -1;
4626 }
4627 if (sscanf(p, "%x:%x:%x.%x%n",
4628 &seg, &bus, &slot, &func, &count) != 4) {
4629 seg = 0;
4630 if (sscanf(p, "%x:%x.%x%n",
4631 &bus, &slot, &func, &count) != 3) {
4632 /* Invalid format */
4633 printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
4634 p);
4635 break;
4636 }
4637 }
4638 p += count;
4639 if (seg == pci_domain_nr(dev->bus) &&
4640 bus == dev->bus->number &&
4641 slot == PCI_SLOT(dev->devfn) &&
4642 func == PCI_FUNC(dev->devfn)) {
4643 if (align_order == -1)
4644 align = PAGE_SIZE;
4645 else
4646 align = 1 << align_order;
4647 /* Found */
4648 break;
4649 }
4650 if (*p != ';' && *p != ',') {
4651 /* End of param or invalid format */
4652 break;
4653 }
4654 p++;
4655 }
4656 spin_unlock(&resource_alignment_lock);
4657 return align;
4658}
4659
4660/*
4661 * This function disables memory decoding and releases memory resources
4662 * of the device specified by kernel's boot parameter 'pci=resource_alignment='.
4663 * It also rounds up size to specified alignment.
4664 * Later on, the kernel will assign page-aligned memory resource back
4665 * to the device.
4666 */
4667void pci_reassigndev_resource_alignment(struct pci_dev *dev)
4668{
4669 int i;
4670 struct resource *r;
4671 resource_size_t align, size;
4672 u16 command;
4673
4674 /* check if specified PCI is target device to reassign */
4675 align = pci_specified_resource_alignment(dev);
4676 if (!align)
4677 return;
4678
4679 if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL &&
4680 (dev->class >> 8) == PCI_CLASS_BRIDGE_HOST) {
4681 dev_warn(&dev->dev,
4682 "Can't reassign resources to host bridge.\n");
4683 return;
4684 }
4685
4686 dev_info(&dev->dev,
4687 "Disabling memory decoding and releasing memory resources.\n");
4688 pci_read_config_word(dev, PCI_COMMAND, &command);
4689 command &= ~PCI_COMMAND_MEMORY;
4690 pci_write_config_word(dev, PCI_COMMAND, command);
4691
4692 for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
4693 r = &dev->resource[i];
4694 if (!(r->flags & IORESOURCE_MEM))
4695 continue;
4696 size = resource_size(r);
4697 if (size < align) {
4698 size = align;
4699 dev_info(&dev->dev,
4700 "Rounding up size of resource #%d to %#llx.\n",
4701 i, (unsigned long long)size);
4702 }
4703 r->flags |= IORESOURCE_UNSET;
4704 r->end = size - 1;
4705 r->start = 0;
4706 }
4707 /* Need to disable bridge's resource window,
4708 * to enable the kernel to reassign new resource
4709 * window later on.
4710 */
4711 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
4712 (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
4713 for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) {
4714 r = &dev->resource[i];
4715 if (!(r->flags & IORESOURCE_MEM))
4716 continue;
4717 r->flags |= IORESOURCE_UNSET;
4718 r->end = resource_size(r) - 1;
4719 r->start = 0;
4720 }
4721 pci_disable_bridge_window(dev);
4722 }
4723}
4724
4725static ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
4726{
4727 if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
4728 count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
4729 spin_lock(&resource_alignment_lock);
4730 strncpy(resource_alignment_param, buf, count);
4731 resource_alignment_param[count] = '\0';
4732 spin_unlock(&resource_alignment_lock);
4733 return count;
4734}
4735
4736static ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
4737{
4738 size_t count;
4739 spin_lock(&resource_alignment_lock);
4740 count = snprintf(buf, size, "%s", resource_alignment_param);
4741 spin_unlock(&resource_alignment_lock);
4742 return count;
4743}
4744
4745static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
4746{
4747 return pci_get_resource_alignment_param(buf, PAGE_SIZE);
4748}
4749
4750static ssize_t pci_resource_alignment_store(struct bus_type *bus,
4751 const char *buf, size_t count)
4752{
4753 return pci_set_resource_alignment_param(buf, count);
4754}
4755
4756BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
4757 pci_resource_alignment_store);
4758
4759static int __init pci_resource_alignment_sysfs_init(void)
4760{
4761 return bus_create_file(&pci_bus_type,
4762 &bus_attr_resource_alignment);
4763}
4764late_initcall(pci_resource_alignment_sysfs_init);
4765
4766static void pci_no_domains(void)
4767{
4768#ifdef CONFIG_PCI_DOMAINS
4769 pci_domains_supported = 0;
4770#endif
4771}
4772
4773#ifdef CONFIG_PCI_DOMAINS
4774static atomic_t __domain_nr = ATOMIC_INIT(-1);
4775
4776int pci_get_new_domain_nr(void)
4777{
4778 return atomic_inc_return(&__domain_nr);
4779}
4780
4781#ifdef CONFIG_PCI_DOMAINS_GENERIC
4782void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent)
4783{
4784 static int use_dt_domains = -1;
4785 int domain = -1;
4786
4787 if (parent)
4788 domain = of_get_pci_domain_nr(parent->of_node);
4789 /*
4790 * Check DT domain and use_dt_domains values.
4791 *
4792 * If DT domain property is valid (domain >= 0) and
4793 * use_dt_domains != 0, the DT assignment is valid since this means
4794 * we have not previously allocated a domain number by using
4795 * pci_get_new_domain_nr(); we should also update use_dt_domains to
4796 * 1, to indicate that we have just assigned a domain number from
4797 * DT.
4798 *
4799 * If DT domain property value is not valid (ie domain < 0), and we
4800 * have not previously assigned a domain number from DT
4801 * (use_dt_domains != 1) we should assign a domain number by
4802 * using the:
4803 *
4804 * pci_get_new_domain_nr()
4805 *
4806 * API and update the use_dt_domains value to keep track of method we
4807 * are using to assign domain numbers (use_dt_domains = 0).
4808 *
4809 * All other combinations imply we have a platform that is trying
4810 * to mix domain numbers obtained from DT and pci_get_new_domain_nr(),
4811 * which is a recipe for domain mishandling and it is prevented by
4812 * invalidating the domain value (domain = -1) and printing a
4813 * corresponding error.
4814 */
4815 if (domain >= 0 && use_dt_domains) {
4816 use_dt_domains = 1;
4817 } else if (domain < 0 && use_dt_domains != 1) {
4818 use_dt_domains = 0;
4819 domain = pci_get_new_domain_nr();
4820 } else {
4821 dev_err(parent, "Node %s has inconsistent \"linux,pci-domain\" property in DT\n",
4822 parent->of_node->full_name);
4823 domain = -1;
4824 }
4825
4826 bus->domain_nr = domain;
4827}
4828#endif
4829#endif
4830
4831/**
4832 * pci_ext_cfg_avail - can we access extended PCI config space?
4833 *
4834 * Returns 1 if we can access PCI extended config space (offsets
4835 * greater than 0xff). This is the default implementation. Architecture
4836 * implementations can override this.
4837 */
4838int __weak pci_ext_cfg_avail(void)
4839{
4840 return 1;
4841}
4842
4843void __weak pci_fixup_cardbus(struct pci_bus *bus)
4844{
4845}
4846EXPORT_SYMBOL(pci_fixup_cardbus);
4847
4848static int __init pci_setup(char *str)
4849{
4850 while (str) {
4851 char *k = strchr(str, ',');
4852 if (k)
4853 *k++ = 0;
4854 if (*str && (str = pcibios_setup(str)) && *str) {
4855 if (!strcmp(str, "nomsi")) {
4856 pci_no_msi();
4857 } else if (!strcmp(str, "noaer")) {
4858 pci_no_aer();
4859 } else if (!strncmp(str, "realloc=", 8)) {
4860 pci_realloc_get_opt(str + 8);
4861 } else if (!strncmp(str, "realloc", 7)) {
4862 pci_realloc_get_opt("on");
4863 } else if (!strcmp(str, "nodomains")) {
4864 pci_no_domains();
4865 } else if (!strncmp(str, "noari", 5)) {
4866 pcie_ari_disabled = true;
4867 } else if (!strncmp(str, "cbiosize=", 9)) {
4868 pci_cardbus_io_size = memparse(str + 9, &str);
4869 } else if (!strncmp(str, "cbmemsize=", 10)) {
4870 pci_cardbus_mem_size = memparse(str + 10, &str);
4871 } else if (!strncmp(str, "resource_alignment=", 19)) {
4872 pci_set_resource_alignment_param(str + 19,
4873 strlen(str + 19));
4874 } else if (!strncmp(str, "ecrc=", 5)) {
4875 pcie_ecrc_get_policy(str + 5);
4876 } else if (!strncmp(str, "hpiosize=", 9)) {
4877 pci_hotplug_io_size = memparse(str + 9, &str);
4878 } else if (!strncmp(str, "hpmemsize=", 10)) {
4879 pci_hotplug_mem_size = memparse(str + 10, &str);
4880 } else if (!strncmp(str, "pcie_bus_tune_off", 17)) {
4881 pcie_bus_config = PCIE_BUS_TUNE_OFF;
4882 } else if (!strncmp(str, "pcie_bus_safe", 13)) {
4883 pcie_bus_config = PCIE_BUS_SAFE;
4884 } else if (!strncmp(str, "pcie_bus_perf", 13)) {
4885 pcie_bus_config = PCIE_BUS_PERFORMANCE;
4886 } else if (!strncmp(str, "pcie_bus_peer2peer", 18)) {
4887 pcie_bus_config = PCIE_BUS_PEER2PEER;
4888 } else if (!strncmp(str, "pcie_scan_all", 13)) {
4889 pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS);
4890 } else {
4891 printk(KERN_ERR "PCI: Unknown option `%s'\n",
4892 str);
4893 }
4894 }
4895 str = k;
4896 }
4897 return 0;
4898}
4899early_param("pci", pci_setup);