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