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  • only in /netgear-R7000-V1.0.7.12_1.2.5/components/opensource/linux/linux-2.6.36/drivers/pci/
1/*
2 *	PCI Bus Services, see include/linux/pci.h for further explanation.
3 *
4 *	Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
5 *	David Mosberger-Tang
6 *
7 *	Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
8 */
9
10#include <linux/kernel.h>
11#include <linux/delay.h>
12#include <linux/init.h>
13#include <linux/pci.h>
14#include <linux/pm.h>
15#include <linux/slab.h>
16#include <linux/module.h>
17#include <linux/spinlock.h>
18#include <linux/string.h>
19#include <linux/log2.h>
20#include <linux/pci-aspm.h>
21#include <linux/pm_wakeup.h>
22#include <linux/interrupt.h>
23#include <linux/device.h>
24#include <linux/pm_runtime.h>
25#include <asm/setup.h>
26#include "pci.h"
27
28const char *pci_power_names[] = {
29	"error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown",
30};
31EXPORT_SYMBOL_GPL(pci_power_names);
32
33int isa_dma_bridge_buggy;
34EXPORT_SYMBOL(isa_dma_bridge_buggy);
35
36int pci_pci_problems;
37EXPORT_SYMBOL(pci_pci_problems);
38
39unsigned int pci_pm_d3_delay;
40
41static void pci_dev_d3_sleep(struct pci_dev *dev)
42{
43	unsigned int delay = dev->d3_delay;
44
45	if (delay < pci_pm_d3_delay)
46		delay = pci_pm_d3_delay;
47
48	msleep(delay);
49}
50
51#ifdef CONFIG_PCI_DOMAINS
52int pci_domains_supported = 1;
53#endif
54
55#define DEFAULT_CARDBUS_IO_SIZE		(256)
56#define DEFAULT_CARDBUS_MEM_SIZE	(64*1024*1024)
57/* pci=cbmemsize=nnM,cbiosize=nn can override this */
58unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
59unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
60
61#define DEFAULT_HOTPLUG_IO_SIZE		(256)
62#define DEFAULT_HOTPLUG_MEM_SIZE	(2*1024*1024)
63/* pci=hpmemsize=nnM,hpiosize=nn can override this */
64unsigned long pci_hotplug_io_size  = DEFAULT_HOTPLUG_IO_SIZE;
65unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE;
66
67/*
68 * The default CLS is used if arch didn't set CLS explicitly and not
69 * all pci devices agree on the same value.  Arch can override either
70 * the dfl or actual value as it sees fit.  Don't forget this is
71 * measured in 32-bit words, not bytes.
72 */
73u8 pci_dfl_cache_line_size __devinitdata = L1_CACHE_BYTES >> 2;
74u8 pci_cache_line_size;
75
76/**
77 * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
78 * @bus: pointer to PCI bus structure to search
79 *
80 * Given a PCI bus, returns the highest PCI bus number present in the set
81 * including the given PCI bus and its list of child PCI buses.
82 */
83unsigned char pci_bus_max_busnr(struct pci_bus* bus)
84{
85	struct list_head *tmp;
86	unsigned char max, n;
87
88	max = bus->subordinate;
89	list_for_each(tmp, &bus->children) {
90		n = pci_bus_max_busnr(pci_bus_b(tmp));
91		if(n > max)
92			max = n;
93	}
94	return max;
95}
96EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
97
98#ifdef CONFIG_HAS_IOMEM
99void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
100{
101	/*
102	 * Make sure the BAR is actually a memory resource, not an IO resource
103	 */
104	if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
105		WARN_ON(1);
106		return NULL;
107	}
108	return ioremap_nocache(pci_resource_start(pdev, bar),
109				     pci_resource_len(pdev, bar));
110}
111EXPORT_SYMBOL_GPL(pci_ioremap_bar);
112#endif
113
114
115#define PCI_FIND_CAP_TTL	48
116
117static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
118				   u8 pos, int cap, int *ttl)
119{
120	u8 id;
121
122	while ((*ttl)--) {
123		pci_bus_read_config_byte(bus, devfn, pos, &pos);
124		if (pos < 0x40)
125			break;
126		pos &= ~3;
127		pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
128					 &id);
129		if (id == 0xff)
130			break;
131		if (id == cap)
132			return pos;
133		pos += PCI_CAP_LIST_NEXT;
134	}
135	return 0;
136}
137
138static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
139			       u8 pos, int cap)
140{
141	int ttl = PCI_FIND_CAP_TTL;
142
143	return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
144}
145
146int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
147{
148	return __pci_find_next_cap(dev->bus, dev->devfn,
149				   pos + PCI_CAP_LIST_NEXT, cap);
150}
151EXPORT_SYMBOL_GPL(pci_find_next_capability);
152
153static int __pci_bus_find_cap_start(struct pci_bus *bus,
154				    unsigned int devfn, u8 hdr_type)
155{
156	u16 status;
157
158	pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
159	if (!(status & PCI_STATUS_CAP_LIST))
160		return 0;
161
162	switch (hdr_type) {
163	case PCI_HEADER_TYPE_NORMAL:
164	case PCI_HEADER_TYPE_BRIDGE:
165		return PCI_CAPABILITY_LIST;
166	case PCI_HEADER_TYPE_CARDBUS:
167		return PCI_CB_CAPABILITY_LIST;
168	default:
169		return 0;
170	}
171
172	return 0;
173}
174
175/**
176 * pci_find_capability - query for devices' capabilities
177 * @dev: PCI device to query
178 * @cap: capability code
179 *
180 * Tell if a device supports a given PCI capability.
181 * Returns the address of the requested capability structure within the
182 * device's PCI configuration space or 0 in case the device does not
183 * support it.  Possible values for @cap:
184 *
185 *  %PCI_CAP_ID_PM           Power Management
186 *  %PCI_CAP_ID_AGP          Accelerated Graphics Port
187 *  %PCI_CAP_ID_VPD          Vital Product Data
188 *  %PCI_CAP_ID_SLOTID       Slot Identification
189 *  %PCI_CAP_ID_MSI          Message Signalled Interrupts
190 *  %PCI_CAP_ID_CHSWP        CompactPCI HotSwap
191 *  %PCI_CAP_ID_PCIX         PCI-X
192 *  %PCI_CAP_ID_EXP          PCI Express
193 */
194int pci_find_capability(struct pci_dev *dev, int cap)
195{
196	int pos;
197
198	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
199	if (pos)
200		pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
201
202	return pos;
203}
204
205/**
206 * pci_bus_find_capability - query for devices' capabilities
207 * @bus:   the PCI bus to query
208 * @devfn: PCI device to query
209 * @cap:   capability code
210 *
211 * Like pci_find_capability() but works for pci devices that do not have a
212 * pci_dev structure set up yet.
213 *
214 * Returns the address of the requested capability structure within the
215 * device's PCI configuration space or 0 in case the device does not
216 * support it.
217 */
218int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
219{
220	int pos;
221	u8 hdr_type;
222
223	pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
224
225	pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
226	if (pos)
227		pos = __pci_find_next_cap(bus, devfn, pos, cap);
228
229	return pos;
230}
231
232/**
233 * pci_find_ext_capability - Find an extended capability
234 * @dev: PCI device to query
235 * @cap: capability code
236 *
237 * Returns the address of the requested extended capability structure
238 * within the device's PCI configuration space or 0 if the device does
239 * not support it.  Possible values for @cap:
240 *
241 *  %PCI_EXT_CAP_ID_ERR		Advanced Error Reporting
242 *  %PCI_EXT_CAP_ID_VC		Virtual Channel
243 *  %PCI_EXT_CAP_ID_DSN		Device Serial Number
244 *  %PCI_EXT_CAP_ID_PWR		Power Budgeting
245 */
246int pci_find_ext_capability(struct pci_dev *dev, int cap)
247{
248	u32 header;
249	int ttl;
250	int pos = PCI_CFG_SPACE_SIZE;
251
252	/* minimum 8 bytes per capability */
253	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
254
255	if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
256		return 0;
257
258	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
259		return 0;
260
261	/*
262	 * If we have no capabilities, this is indicated by cap ID,
263	 * cap version and next pointer all being 0.
264	 */
265	if (header == 0)
266		return 0;
267
268	while (ttl-- > 0) {
269		if (PCI_EXT_CAP_ID(header) == cap)
270			return pos;
271
272		pos = PCI_EXT_CAP_NEXT(header);
273		if (pos < PCI_CFG_SPACE_SIZE)
274			break;
275
276		if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
277			break;
278	}
279
280	return 0;
281}
282EXPORT_SYMBOL_GPL(pci_find_ext_capability);
283
284/**
285 * pci_bus_find_ext_capability - find an extended capability
286 * @bus:   the PCI bus to query
287 * @devfn: PCI device to query
288 * @cap:   capability code
289 *
290 * Like pci_find_ext_capability() but works for pci devices that do not have a
291 * pci_dev structure set up yet.
292 *
293 * Returns the address of the requested capability structure within the
294 * device's PCI configuration space or 0 in case the device does not
295 * support it.
296 */
297int pci_bus_find_ext_capability(struct pci_bus *bus, unsigned int devfn,
298				int cap)
299{
300	u32 header;
301	int ttl;
302	int pos = PCI_CFG_SPACE_SIZE;
303
304	/* minimum 8 bytes per capability */
305	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
306
307	if (!pci_bus_read_config_dword(bus, devfn, pos, &header))
308		return 0;
309	if (header == 0xffffffff || header == 0)
310		return 0;
311
312	while (ttl-- > 0) {
313		if (PCI_EXT_CAP_ID(header) == cap)
314			return pos;
315
316		pos = PCI_EXT_CAP_NEXT(header);
317		if (pos < PCI_CFG_SPACE_SIZE)
318			break;
319
320		if (!pci_bus_read_config_dword(bus, devfn, pos, &header))
321			break;
322	}
323
324	return 0;
325}
326
327static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
328{
329	int rc, ttl = PCI_FIND_CAP_TTL;
330	u8 cap, mask;
331
332	if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
333		mask = HT_3BIT_CAP_MASK;
334	else
335		mask = HT_5BIT_CAP_MASK;
336
337	pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
338				      PCI_CAP_ID_HT, &ttl);
339	while (pos) {
340		rc = pci_read_config_byte(dev, pos + 3, &cap);
341		if (rc != PCIBIOS_SUCCESSFUL)
342			return 0;
343
344		if ((cap & mask) == ht_cap)
345			return pos;
346
347		pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
348					      pos + PCI_CAP_LIST_NEXT,
349					      PCI_CAP_ID_HT, &ttl);
350	}
351
352	return 0;
353}
354/**
355 * pci_find_next_ht_capability - query a device's Hypertransport capabilities
356 * @dev: PCI device to query
357 * @pos: Position from which to continue searching
358 * @ht_cap: Hypertransport capability code
359 *
360 * To be used in conjunction with pci_find_ht_capability() to search for
361 * all capabilities matching @ht_cap. @pos should always be a value returned
362 * from pci_find_ht_capability().
363 *
364 * NB. To be 100% safe against broken PCI devices, the caller should take
365 * steps to avoid an infinite loop.
366 */
367int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
368{
369	return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
370}
371EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
372
373/**
374 * pci_find_ht_capability - query a device's Hypertransport capabilities
375 * @dev: PCI device to query
376 * @ht_cap: Hypertransport capability code
377 *
378 * Tell if a device supports a given Hypertransport capability.
379 * Returns an address within the device's PCI configuration space
380 * or 0 in case the device does not support the request capability.
381 * The address points to the PCI capability, of type PCI_CAP_ID_HT,
382 * which has a Hypertransport capability matching @ht_cap.
383 */
384int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
385{
386	int pos;
387
388	pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
389	if (pos)
390		pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
391
392	return pos;
393}
394EXPORT_SYMBOL_GPL(pci_find_ht_capability);
395
396/**
397 * pci_find_parent_resource - return resource region of parent bus of given region
398 * @dev: PCI device structure contains resources to be searched
399 * @res: child resource record for which parent is sought
400 *
401 *  For given resource region of given device, return the resource
402 *  region of parent bus the given region is contained in or where
403 *  it should be allocated from.
404 */
405struct resource *
406pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
407{
408	const struct pci_bus *bus = dev->bus;
409	int i;
410	struct resource *best = NULL, *r;
411
412	pci_bus_for_each_resource(bus, r, i) {
413		if (!r)
414			continue;
415		if (res->start && !(res->start >= r->start && res->end <= r->end))
416			continue;	/* Not contained */
417		if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
418			continue;	/* Wrong type */
419		if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
420			return r;	/* Exact match */
421		/* We can't insert a non-prefetch resource inside a prefetchable parent .. */
422		if (r->flags & IORESOURCE_PREFETCH)
423			continue;
424		/* .. but we can put a prefetchable resource inside a non-prefetchable one */
425		if (!best)
426			best = r;
427	}
428	return best;
429}
430
431/**
432 * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
433 * @dev: PCI device to have its BARs restored
434 *
435 * Restore the BAR values for a given device, so as to make it
436 * accessible by its driver.
437 */
438static void
439pci_restore_bars(struct pci_dev *dev)
440{
441	int i;
442
443	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++)
444		pci_update_resource(dev, i);
445}
446
447static struct pci_platform_pm_ops *pci_platform_pm;
448
449int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
450{
451	if (!ops->is_manageable || !ops->set_state || !ops->choose_state
452	    || !ops->sleep_wake || !ops->can_wakeup)
453		return -EINVAL;
454	pci_platform_pm = ops;
455	return 0;
456}
457
458static inline bool platform_pci_power_manageable(struct pci_dev *dev)
459{
460	return pci_platform_pm ? pci_platform_pm->is_manageable(dev) : false;
461}
462
463static inline int platform_pci_set_power_state(struct pci_dev *dev,
464                                                pci_power_t t)
465{
466	return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS;
467}
468
469static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
470{
471	return pci_platform_pm ?
472			pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
473}
474
475static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
476{
477	return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
478}
479
480static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
481{
482	return pci_platform_pm ?
483			pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
484}
485
486static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable)
487{
488	return pci_platform_pm ?
489			pci_platform_pm->run_wake(dev, enable) : -ENODEV;
490}
491
492/**
493 * pci_raw_set_power_state - Use PCI PM registers to set the power state of
494 *                           given PCI device
495 * @dev: PCI device to handle.
496 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
497 *
498 * RETURN VALUE:
499 * -EINVAL if the requested state is invalid.
500 * -EIO if device does not support PCI PM or its PM capabilities register has a
501 * wrong version, or device doesn't support the requested state.
502 * 0 if device already is in the requested state.
503 * 0 if device's power state has been successfully changed.
504 */
505static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
506{
507	u16 pmcsr;
508	bool need_restore = false;
509
510	/* Check if we're already there */
511	if (dev->current_state == state)
512		return 0;
513
514	if (!dev->pm_cap)
515		return -EIO;
516
517	if (state < PCI_D0 || state > PCI_D3hot)
518		return -EINVAL;
519
520	/* Validate current state:
521	 * Can enter D0 from any state, but if we can only go deeper
522	 * to sleep if we're already in a low power state
523	 */
524	if (state != PCI_D0 && dev->current_state <= PCI_D3cold
525	    && dev->current_state > state) {
526		dev_err(&dev->dev, "invalid power transition "
527			"(from state %d to %d)\n", dev->current_state, state);
528		return -EINVAL;
529	}
530
531	/* check if this device supports the desired state */
532	if ((state == PCI_D1 && !dev->d1_support)
533	   || (state == PCI_D2 && !dev->d2_support))
534		return -EIO;
535
536	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
537
538	/* If we're (effectively) in D3, force entire word to 0.
539	 * This doesn't affect PME_Status, disables PME_En, and
540	 * sets PowerState to 0.
541	 */
542	switch (dev->current_state) {
543	case PCI_D0:
544	case PCI_D1:
545	case PCI_D2:
546		pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
547		pmcsr |= state;
548		break;
549	case PCI_D3hot:
550	case PCI_D3cold:
551	case PCI_UNKNOWN: /* Boot-up */
552		if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
553		 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
554			need_restore = true;
555		/* Fall-through: force to D0 */
556	default:
557		pmcsr = 0;
558		break;
559	}
560
561	/* enter specified state */
562	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
563
564	/* Mandatory power management transition delays */
565	/* see PCI PM 1.1 5.6.1 table 18 */
566	if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
567		pci_dev_d3_sleep(dev);
568	else if (state == PCI_D2 || dev->current_state == PCI_D2)
569		udelay(PCI_PM_D2_DELAY);
570
571	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
572	dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
573	if (dev->current_state != state && printk_ratelimit())
574		dev_info(&dev->dev, "Refused to change power state, "
575			"currently in D%d\n", dev->current_state);
576
577	/* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
578	 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
579	 * from D3hot to D0 _may_ perform an internal reset, thereby
580	 * going to "D0 Uninitialized" rather than "D0 Initialized".
581	 * For example, at least some versions of the 3c905B and the
582	 * 3c556B exhibit this behaviour.
583	 *
584	 * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
585	 * devices in a D3hot state at boot.  Consequently, we need to
586	 * restore at least the BARs so that the device will be
587	 * accessible to its driver.
588	 */
589	if (need_restore)
590		pci_restore_bars(dev);
591
592	if (dev->bus->self)
593		pcie_aspm_pm_state_change(dev->bus->self);
594
595	return 0;
596}
597
598/**
599 * pci_update_current_state - Read PCI power state of given device from its
600 *                            PCI PM registers and cache it
601 * @dev: PCI device to handle.
602 * @state: State to cache in case the device doesn't have the PM capability
603 */
604void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
605{
606	if (dev->pm_cap) {
607		u16 pmcsr;
608
609		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
610		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
611	} else {
612		dev->current_state = state;
613	}
614}
615
616/**
617 * pci_platform_power_transition - Use platform to change device power state
618 * @dev: PCI device to handle.
619 * @state: State to put the device into.
620 */
621static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
622{
623	int error;
624
625	if (platform_pci_power_manageable(dev)) {
626		error = platform_pci_set_power_state(dev, state);
627		if (!error)
628			pci_update_current_state(dev, state);
629	} else {
630		error = -ENODEV;
631		/* Fall back to PCI_D0 if native PM is not supported */
632		if (!dev->pm_cap)
633			dev->current_state = PCI_D0;
634	}
635
636	return error;
637}
638
639/**
640 * __pci_start_power_transition - Start power transition of a PCI device
641 * @dev: PCI device to handle.
642 * @state: State to put the device into.
643 */
644static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
645{
646	if (state == PCI_D0)
647		pci_platform_power_transition(dev, PCI_D0);
648}
649
650/**
651 * __pci_complete_power_transition - Complete power transition of a PCI device
652 * @dev: PCI device to handle.
653 * @state: State to put the device into.
654 *
655 * This function should not be called directly by device drivers.
656 */
657int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
658{
659	return state >= PCI_D0 ?
660			pci_platform_power_transition(dev, state) : -EINVAL;
661}
662EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
663
664/**
665 * pci_set_power_state - Set the power state of a PCI device
666 * @dev: PCI device to handle.
667 * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
668 *
669 * Transition a device to a new power state, using the platform firmware and/or
670 * the device's PCI PM registers.
671 *
672 * RETURN VALUE:
673 * -EINVAL if the requested state is invalid.
674 * -EIO if device does not support PCI PM or its PM capabilities register has a
675 * wrong version, or device doesn't support the requested state.
676 * 0 if device already is in the requested state.
677 * 0 if device's power state has been successfully changed.
678 */
679int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
680{
681	int error;
682
683	/* bound the state we're entering */
684	if (state > PCI_D3hot)
685		state = PCI_D3hot;
686	else if (state < PCI_D0)
687		state = PCI_D0;
688	else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
689		/*
690		 * If the device or the parent bridge do not support PCI PM,
691		 * ignore the request if we're doing anything other than putting
692		 * it into D0 (which would only happen on boot).
693		 */
694		return 0;
695
696	__pci_start_power_transition(dev, state);
697
698	/* This device is quirked not to be put into D3, so
699	   don't put it in D3 */
700	if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
701		return 0;
702
703	error = pci_raw_set_power_state(dev, state);
704
705	if (!__pci_complete_power_transition(dev, state))
706		error = 0;
707
708	return error;
709}
710
711/**
712 * pci_choose_state - Choose the power state of a PCI device
713 * @dev: PCI device to be suspended
714 * @state: target sleep state for the whole system. This is the value
715 *	that is passed to suspend() function.
716 *
717 * Returns PCI power state suitable for given device and given system
718 * message.
719 */
720
721pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
722{
723	pci_power_t ret;
724
725	if (!pci_find_capability(dev, PCI_CAP_ID_PM))
726		return PCI_D0;
727
728	ret = platform_pci_choose_state(dev);
729	if (ret != PCI_POWER_ERROR)
730		return ret;
731
732	switch (state.event) {
733	case PM_EVENT_ON:
734		return PCI_D0;
735	case PM_EVENT_FREEZE:
736	case PM_EVENT_PRETHAW:
737		/* REVISIT both freeze and pre-thaw "should" use D0 */
738	case PM_EVENT_SUSPEND:
739	case PM_EVENT_HIBERNATE:
740		return PCI_D3hot;
741	default:
742		dev_info(&dev->dev, "unrecognized suspend event %d\n",
743			 state.event);
744		BUG();
745	}
746	return PCI_D0;
747}
748
749EXPORT_SYMBOL(pci_choose_state);
750
751#define PCI_EXP_SAVE_REGS	7
752
753#define pcie_cap_has_devctl(type, flags)	1
754#define pcie_cap_has_lnkctl(type, flags)		\
755		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
756		 (type == PCI_EXP_TYPE_ROOT_PORT ||	\
757		  type == PCI_EXP_TYPE_ENDPOINT ||	\
758		  type == PCI_EXP_TYPE_LEG_END))
759#define pcie_cap_has_sltctl(type, flags)		\
760		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
761		 ((type == PCI_EXP_TYPE_ROOT_PORT) ||	\
762		  (type == PCI_EXP_TYPE_DOWNSTREAM &&	\
763		   (flags & PCI_EXP_FLAGS_SLOT))))
764#define pcie_cap_has_rtctl(type, flags)			\
765		((flags & PCI_EXP_FLAGS_VERS) > 1 ||	\
766		 (type == PCI_EXP_TYPE_ROOT_PORT ||	\
767		  type == PCI_EXP_TYPE_RC_EC))
768#define pcie_cap_has_devctl2(type, flags)		\
769		((flags & PCI_EXP_FLAGS_VERS) > 1)
770#define pcie_cap_has_lnkctl2(type, flags)		\
771		((flags & PCI_EXP_FLAGS_VERS) > 1)
772#define pcie_cap_has_sltctl2(type, flags)		\
773		((flags & PCI_EXP_FLAGS_VERS) > 1)
774
775static int pci_save_pcie_state(struct pci_dev *dev)
776{
777	int pos, i = 0;
778	struct pci_cap_saved_state *save_state;
779	u16 *cap;
780	u16 flags;
781
782	pos = pci_pcie_cap(dev);
783	if (!pos)
784		return 0;
785
786	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
787	if (!save_state) {
788		dev_err(&dev->dev, "buffer not found in %s\n", __func__);
789		return -ENOMEM;
790	}
791	cap = (u16 *)&save_state->data[0];
792
793	pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
794
795	if (pcie_cap_has_devctl(dev->pcie_type, flags))
796		pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
797	if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
798		pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
799	if (pcie_cap_has_sltctl(dev->pcie_type, flags))
800		pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
801	if (pcie_cap_has_rtctl(dev->pcie_type, flags))
802		pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
803	if (pcie_cap_has_devctl2(dev->pcie_type, flags))
804		pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &cap[i++]);
805	if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
806		pci_read_config_word(dev, pos + PCI_EXP_LNKCTL2, &cap[i++]);
807	if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
808		pci_read_config_word(dev, pos + PCI_EXP_SLTCTL2, &cap[i++]);
809
810	return 0;
811}
812
813static void pci_restore_pcie_state(struct pci_dev *dev)
814{
815	int i = 0, pos;
816	struct pci_cap_saved_state *save_state;
817	u16 *cap;
818	u16 flags;
819
820	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
821	pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
822	if (!save_state || pos <= 0)
823		return;
824	cap = (u16 *)&save_state->data[0];
825
826	pci_read_config_word(dev, pos + PCI_EXP_FLAGS, &flags);
827
828	if (pcie_cap_has_devctl(dev->pcie_type, flags))
829		pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
830	if (pcie_cap_has_lnkctl(dev->pcie_type, flags))
831		pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
832	if (pcie_cap_has_sltctl(dev->pcie_type, flags))
833		pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
834	if (pcie_cap_has_rtctl(dev->pcie_type, flags))
835		pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
836	if (pcie_cap_has_devctl2(dev->pcie_type, flags))
837		pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, cap[i++]);
838	if (pcie_cap_has_lnkctl2(dev->pcie_type, flags))
839		pci_write_config_word(dev, pos + PCI_EXP_LNKCTL2, cap[i++]);
840	if (pcie_cap_has_sltctl2(dev->pcie_type, flags))
841		pci_write_config_word(dev, pos + PCI_EXP_SLTCTL2, cap[i++]);
842}
843
844
845static int pci_save_pcix_state(struct pci_dev *dev)
846{
847	int pos;
848	struct pci_cap_saved_state *save_state;
849
850	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
851	if (pos <= 0)
852		return 0;
853
854	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
855	if (!save_state) {
856		dev_err(&dev->dev, "buffer not found in %s\n", __func__);
857		return -ENOMEM;
858	}
859
860	pci_read_config_word(dev, pos + PCI_X_CMD, (u16 *)save_state->data);
861
862	return 0;
863}
864
865static void pci_restore_pcix_state(struct pci_dev *dev)
866{
867	int i = 0, pos;
868	struct pci_cap_saved_state *save_state;
869	u16 *cap;
870
871	save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
872	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
873	if (!save_state || pos <= 0)
874		return;
875	cap = (u16 *)&save_state->data[0];
876
877	pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
878}
879
880
881/**
882 * pci_save_state - save the PCI configuration space of a device before suspending
883 * @dev: - PCI device that we're dealing with
884 */
885int
886pci_save_state(struct pci_dev *dev)
887{
888	int i;
889	for (i = 0; i < 16; i++)
890		pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]);
891	dev->state_saved = true;
892	if ((i = pci_save_pcie_state(dev)) != 0)
893		return i;
894	if ((i = pci_save_pcix_state(dev)) != 0)
895		return i;
896	return 0;
897}
898
899/**
900 * pci_restore_state - Restore the saved state of a PCI device
901 * @dev: - PCI device that we're dealing with
902 */
903int
904pci_restore_state(struct pci_dev *dev)
905{
906	int i;
907	u32 val;
908
909	if (!dev->state_saved)
910		return 0;
911
912	/* PCI Express register must be restored first */
913	pci_restore_pcie_state(dev);
914
915	/*
916	 * The Base Address register should be programmed before the command
917	 * register(s)
918	 */
919	for (i = 15; i >= 0; i--) {
920		pci_read_config_dword(dev, i * 4, &val);
921		if (val != dev->saved_config_space[i]) {
922			dev_printk(KERN_DEBUG, &dev->dev, "restoring config "
923				"space at offset %#x (was %#x, writing %#x)\n",
924				i, val, (int)dev->saved_config_space[i]);
925			pci_write_config_dword(dev,i * 4,
926				dev->saved_config_space[i]);
927		}
928	}
929	pci_restore_pcix_state(dev);
930	pci_restore_msi_state(dev);
931	pci_restore_iov_state(dev);
932
933	dev->state_saved = false;
934
935	return 0;
936}
937
938static int do_pci_enable_device(struct pci_dev *dev, int bars)
939{
940	int err;
941
942	err = pci_set_power_state(dev, PCI_D0);
943	if (err < 0 && err != -EIO)
944		return err;
945	err = pcibios_enable_device(dev, bars);
946	if (err < 0)
947		return err;
948	pci_fixup_device(pci_fixup_enable, dev);
949
950	return 0;
951}
952
953/**
954 * pci_reenable_device - Resume abandoned device
955 * @dev: PCI device to be resumed
956 *
957 *  Note this function is a backend of pci_default_resume and is not supposed
958 *  to be called by normal code, write proper resume handler and use it instead.
959 */
960int pci_reenable_device(struct pci_dev *dev)
961{
962	if (pci_is_enabled(dev))
963		return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
964	return 0;
965}
966
967static int __pci_enable_device_flags(struct pci_dev *dev,
968				     resource_size_t flags)
969{
970	int err;
971	int i, bars = 0;
972
973	if (atomic_add_return(1, &dev->enable_cnt) > 1)
974		return 0;		/* already enabled */
975
976	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
977		if (dev->resource[i].flags & flags)
978			bars |= (1 << i);
979
980	err = do_pci_enable_device(dev, bars);
981	if (err < 0)
982		atomic_dec(&dev->enable_cnt);
983	return err;
984}
985
986/**
987 * pci_enable_device_io - Initialize a device for use with IO space
988 * @dev: PCI device to be initialized
989 *
990 *  Initialize device before it's used by a driver. Ask low-level code
991 *  to enable I/O resources. Wake up the device if it was suspended.
992 *  Beware, this function can fail.
993 */
994int pci_enable_device_io(struct pci_dev *dev)
995{
996	return __pci_enable_device_flags(dev, IORESOURCE_IO);
997}
998
999/**
1000 * pci_enable_device_mem - Initialize a device for use with Memory space
1001 * @dev: PCI device to be initialized
1002 *
1003 *  Initialize device before it's used by a driver. Ask low-level code
1004 *  to enable Memory resources. Wake up the device if it was suspended.
1005 *  Beware, this function can fail.
1006 */
1007int pci_enable_device_mem(struct pci_dev *dev)
1008{
1009	return __pci_enable_device_flags(dev, IORESOURCE_MEM);
1010}
1011
1012/**
1013 * pci_enable_device - Initialize device before it's used by a driver.
1014 * @dev: PCI device to be initialized
1015 *
1016 *  Initialize device before it's used by a driver. Ask low-level code
1017 *  to enable I/O and memory. Wake up the device if it was suspended.
1018 *  Beware, this function can fail.
1019 *
1020 *  Note we don't actually enable the device many times if we call
1021 *  this function repeatedly (we just increment the count).
1022 */
1023int pci_enable_device(struct pci_dev *dev)
1024{
1025	return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
1026}
1027
1028/*
1029 * Managed PCI resources.  This manages device on/off, intx/msi/msix
1030 * on/off and BAR regions.  pci_dev itself records msi/msix status, so
1031 * there's no need to track it separately.  pci_devres is initialized
1032 * when a device is enabled using managed PCI device enable interface.
1033 */
1034struct pci_devres {
1035	unsigned int enabled:1;
1036	unsigned int pinned:1;
1037	unsigned int orig_intx:1;
1038	unsigned int restore_intx:1;
1039	u32 region_mask;
1040};
1041
1042static void pcim_release(struct device *gendev, void *res)
1043{
1044	struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
1045	struct pci_devres *this = res;
1046	int i;
1047
1048	if (dev->msi_enabled)
1049		pci_disable_msi(dev);
1050	if (dev->msix_enabled)
1051		pci_disable_msix(dev);
1052
1053	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
1054		if (this->region_mask & (1 << i))
1055			pci_release_region(dev, i);
1056
1057	if (this->restore_intx)
1058		pci_intx(dev, this->orig_intx);
1059
1060	if (this->enabled && !this->pinned)
1061		pci_disable_device(dev);
1062}
1063
1064static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
1065{
1066	struct pci_devres *dr, *new_dr;
1067
1068	dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
1069	if (dr)
1070		return dr;
1071
1072	new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
1073	if (!new_dr)
1074		return NULL;
1075	return devres_get(&pdev->dev, new_dr, NULL, NULL);
1076}
1077
1078static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
1079{
1080	if (pci_is_managed(pdev))
1081		return devres_find(&pdev->dev, pcim_release, NULL, NULL);
1082	return NULL;
1083}
1084
1085/**
1086 * pcim_enable_device - Managed pci_enable_device()
1087 * @pdev: PCI device to be initialized
1088 *
1089 * Managed pci_enable_device().
1090 */
1091int pcim_enable_device(struct pci_dev *pdev)
1092{
1093	struct pci_devres *dr;
1094	int rc;
1095
1096	dr = get_pci_dr(pdev);
1097	if (unlikely(!dr))
1098		return -ENOMEM;
1099	if (dr->enabled)
1100		return 0;
1101
1102	rc = pci_enable_device(pdev);
1103	if (!rc) {
1104		pdev->is_managed = 1;
1105		dr->enabled = 1;
1106	}
1107	return rc;
1108}
1109
1110/**
1111 * pcim_pin_device - Pin managed PCI device
1112 * @pdev: PCI device to pin
1113 *
1114 * Pin managed PCI device @pdev.  Pinned device won't be disabled on
1115 * driver detach.  @pdev must have been enabled with
1116 * pcim_enable_device().
1117 */
1118void pcim_pin_device(struct pci_dev *pdev)
1119{
1120	struct pci_devres *dr;
1121
1122	dr = find_pci_dr(pdev);
1123	WARN_ON(!dr || !dr->enabled);
1124	if (dr)
1125		dr->pinned = 1;
1126}
1127
1128/**
1129 * pcibios_disable_device - disable arch specific PCI resources for device dev
1130 * @dev: the PCI device to disable
1131 *
1132 * Disables architecture specific PCI resources for the device. This
1133 * is the default implementation. Architecture implementations can
1134 * override this.
1135 */
1136void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
1137
1138static void do_pci_disable_device(struct pci_dev *dev)
1139{
1140	u16 pci_command;
1141
1142	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
1143	if (pci_command & PCI_COMMAND_MASTER) {
1144		pci_command &= ~PCI_COMMAND_MASTER;
1145		pci_write_config_word(dev, PCI_COMMAND, pci_command);
1146	}
1147
1148	pcibios_disable_device(dev);
1149}
1150
1151/**
1152 * pci_disable_enabled_device - Disable device without updating enable_cnt
1153 * @dev: PCI device to disable
1154 *
1155 * NOTE: This function is a backend of PCI power management routines and is
1156 * not supposed to be called drivers.
1157 */
1158void pci_disable_enabled_device(struct pci_dev *dev)
1159{
1160	if (pci_is_enabled(dev))
1161		do_pci_disable_device(dev);
1162}
1163
1164/**
1165 * pci_disable_device - Disable PCI device after use
1166 * @dev: PCI device to be disabled
1167 *
1168 * Signal to the system that the PCI device is not in use by the system
1169 * anymore.  This only involves disabling PCI bus-mastering, if active.
1170 *
1171 * Note we don't actually disable the device until all callers of
1172 * pci_enable_device() have called pci_disable_device().
1173 */
1174void
1175pci_disable_device(struct pci_dev *dev)
1176{
1177	struct pci_devres *dr;
1178
1179	dr = find_pci_dr(dev);
1180	if (dr)
1181		dr->enabled = 0;
1182
1183	if (atomic_sub_return(1, &dev->enable_cnt) != 0)
1184		return;
1185
1186	do_pci_disable_device(dev);
1187
1188	dev->is_busmaster = 0;
1189}
1190
1191/**
1192 * pcibios_set_pcie_reset_state - set reset state for device dev
1193 * @dev: the PCIe device reset
1194 * @state: Reset state to enter into
1195 *
1196 *
1197 * Sets the PCIe reset state for the device. This is the default
1198 * implementation. Architecture implementations can override this.
1199 */
1200int __attribute__ ((weak)) pcibios_set_pcie_reset_state(struct pci_dev *dev,
1201							enum pcie_reset_state state)
1202{
1203	return -EINVAL;
1204}
1205
1206/**
1207 * pci_set_pcie_reset_state - set reset state for device dev
1208 * @dev: the PCIe device reset
1209 * @state: Reset state to enter into
1210 *
1211 *
1212 * Sets the PCI reset state for the device.
1213 */
1214int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
1215{
1216	return pcibios_set_pcie_reset_state(dev, state);
1217}
1218
1219/**
1220 * pci_check_pme_status - Check if given device has generated PME.
1221 * @dev: Device to check.
1222 *
1223 * Check the PME status of the device and if set, clear it and clear PME enable
1224 * (if set).  Return 'true' if PME status and PME enable were both set or
1225 * 'false' otherwise.
1226 */
1227bool pci_check_pme_status(struct pci_dev *dev)
1228{
1229	int pmcsr_pos;
1230	u16 pmcsr;
1231	bool ret = false;
1232
1233	if (!dev->pm_cap)
1234		return false;
1235
1236	pmcsr_pos = dev->pm_cap + PCI_PM_CTRL;
1237	pci_read_config_word(dev, pmcsr_pos, &pmcsr);
1238	if (!(pmcsr & PCI_PM_CTRL_PME_STATUS))
1239		return false;
1240
1241	/* Clear PME status. */
1242	pmcsr |= PCI_PM_CTRL_PME_STATUS;
1243	if (pmcsr & PCI_PM_CTRL_PME_ENABLE) {
1244		/* Disable PME to avoid interrupt flood. */
1245		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1246		ret = true;
1247	}
1248
1249	pci_write_config_word(dev, pmcsr_pos, pmcsr);
1250
1251	return ret;
1252}
1253
1254/*
1255 * Time to wait before the system can be put into a sleep state after reporting
1256 * a wakeup event signaled by a PCI device.
1257 */
1258#define PCI_WAKEUP_COOLDOWN	100
1259
1260/**
1261 * pci_wakeup_event - Report a wakeup event related to a given PCI device.
1262 * @dev: Device to report the wakeup event for.
1263 */
1264void pci_wakeup_event(struct pci_dev *dev)
1265{
1266	if (device_may_wakeup(&dev->dev))
1267		pm_wakeup_event(&dev->dev, PCI_WAKEUP_COOLDOWN);
1268}
1269
1270/**
1271 * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
1272 * @dev: Device to handle.
1273 * @ign: Ignored.
1274 *
1275 * Check if @dev has generated PME and queue a resume request for it in that
1276 * case.
1277 */
1278static int pci_pme_wakeup(struct pci_dev *dev, void *ign)
1279{
1280	if (pci_check_pme_status(dev)) {
1281		pm_request_resume(&dev->dev);
1282		pci_wakeup_event(dev);
1283	}
1284	return 0;
1285}
1286
1287/**
1288 * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
1289 * @bus: Top bus of the subtree to walk.
1290 */
1291void pci_pme_wakeup_bus(struct pci_bus *bus)
1292{
1293	if (bus)
1294		pci_walk_bus(bus, pci_pme_wakeup, NULL);
1295}
1296
1297/**
1298 * pci_pme_capable - check the capability of PCI device to generate PME#
1299 * @dev: PCI device to handle.
1300 * @state: PCI state from which device will issue PME#.
1301 */
1302bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
1303{
1304	if (!dev->pm_cap)
1305		return false;
1306
1307	return !!(dev->pme_support & (1 << state));
1308}
1309
1310/**
1311 * pci_pme_active - enable or disable PCI device's PME# function
1312 * @dev: PCI device to handle.
1313 * @enable: 'true' to enable PME# generation; 'false' to disable it.
1314 *
1315 * The caller must verify that the device is capable of generating PME# before
1316 * calling this function with @enable equal to 'true'.
1317 */
1318void pci_pme_active(struct pci_dev *dev, bool enable)
1319{
1320	u16 pmcsr;
1321
1322	if (!dev->pm_cap)
1323		return;
1324
1325	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
1326	/* Clear PME_Status by writing 1 to it and enable PME# */
1327	pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
1328	if (!enable)
1329		pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
1330
1331	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
1332
1333	dev_printk(KERN_DEBUG, &dev->dev, "PME# %s\n",
1334			enable ? "enabled" : "disabled");
1335}
1336
1337/**
1338 * __pci_enable_wake - enable PCI device as wakeup event source
1339 * @dev: PCI device affected
1340 * @state: PCI state from which device will issue wakeup events
1341 * @runtime: True if the events are to be generated at run time
1342 * @enable: True to enable event generation; false to disable
1343 *
1344 * This enables the device as a wakeup event source, or disables it.
1345 * When such events involves platform-specific hooks, those hooks are
1346 * called automatically by this routine.
1347 *
1348 * Devices with legacy power management (no standard PCI PM capabilities)
1349 * always require such platform hooks.
1350 *
1351 * RETURN VALUE:
1352 * 0 is returned on success
1353 * -EINVAL is returned if device is not supposed to wake up the system
1354 * Error code depending on the platform is returned if both the platform and
1355 * the native mechanism fail to enable the generation of wake-up events
1356 */
1357int __pci_enable_wake(struct pci_dev *dev, pci_power_t state,
1358		      bool runtime, bool enable)
1359{
1360	int ret = 0;
1361
1362	if (enable && !runtime && !device_may_wakeup(&dev->dev))
1363		return -EINVAL;
1364
1365	/* Don't do the same thing twice in a row for one device. */
1366	if (!!enable == !!dev->wakeup_prepared)
1367		return 0;
1368
1369	/*
1370	 * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
1371	 * Anderson we should be doing PME# wake enable followed by ACPI wake
1372	 * enable.  To disable wake-up we call the platform first, for symmetry.
1373	 */
1374
1375	if (enable) {
1376		int error;
1377
1378		if (pci_pme_capable(dev, state))
1379			pci_pme_active(dev, true);
1380		else
1381			ret = 1;
1382		error = runtime ? platform_pci_run_wake(dev, true) :
1383					platform_pci_sleep_wake(dev, true);
1384		if (ret)
1385			ret = error;
1386		if (!ret)
1387			dev->wakeup_prepared = true;
1388	} else {
1389		if (runtime)
1390			platform_pci_run_wake(dev, false);
1391		else
1392			platform_pci_sleep_wake(dev, false);
1393		pci_pme_active(dev, false);
1394		dev->wakeup_prepared = false;
1395	}
1396
1397	return ret;
1398}
1399EXPORT_SYMBOL(__pci_enable_wake);
1400
1401/**
1402 * pci_wake_from_d3 - enable/disable device to wake up from D3_hot or D3_cold
1403 * @dev: PCI device to prepare
1404 * @enable: True to enable wake-up event generation; false to disable
1405 *
1406 * Many drivers want the device to wake up the system from D3_hot or D3_cold
1407 * and this function allows them to set that up cleanly - pci_enable_wake()
1408 * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI
1409 * ordering constraints.
1410 *
1411 * This function only returns error code if the device is not capable of
1412 * generating PME# from both D3_hot and D3_cold, and the platform is unable to
1413 * enable wake-up power for it.
1414 */
1415int pci_wake_from_d3(struct pci_dev *dev, bool enable)
1416{
1417	return pci_pme_capable(dev, PCI_D3cold) ?
1418			pci_enable_wake(dev, PCI_D3cold, enable) :
1419			pci_enable_wake(dev, PCI_D3hot, enable);
1420}
1421
1422/**
1423 * pci_target_state - find an appropriate low power state for a given PCI dev
1424 * @dev: PCI device
1425 *
1426 * Use underlying platform code to find a supported low power state for @dev.
1427 * If the platform can't manage @dev, return the deepest state from which it
1428 * can generate wake events, based on any available PME info.
1429 */
1430pci_power_t pci_target_state(struct pci_dev *dev)
1431{
1432	pci_power_t target_state = PCI_D3hot;
1433
1434	if (platform_pci_power_manageable(dev)) {
1435		/*
1436		 * Call the platform to choose the target state of the device
1437		 * and enable wake-up from this state if supported.
1438		 */
1439		pci_power_t state = platform_pci_choose_state(dev);
1440
1441		switch (state) {
1442		case PCI_POWER_ERROR:
1443		case PCI_UNKNOWN:
1444			break;
1445		case PCI_D1:
1446		case PCI_D2:
1447			if (pci_no_d1d2(dev))
1448				break;
1449		default:
1450			target_state = state;
1451		}
1452	} else if (!dev->pm_cap) {
1453		target_state = PCI_D0;
1454	} else if (device_may_wakeup(&dev->dev)) {
1455		/*
1456		 * Find the deepest state from which the device can generate
1457		 * wake-up events, make it the target state and enable device
1458		 * to generate PME#.
1459		 */
1460		if (dev->pme_support) {
1461			while (target_state
1462			      && !(dev->pme_support & (1 << target_state)))
1463				target_state--;
1464		}
1465	}
1466
1467	return target_state;
1468}
1469
1470/**
1471 * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
1472 * @dev: Device to handle.
1473 *
1474 * Choose the power state appropriate for the device depending on whether
1475 * it can wake up the system and/or is power manageable by the platform
1476 * (PCI_D3hot is the default) and put the device into that state.
1477 */
1478int pci_prepare_to_sleep(struct pci_dev *dev)
1479{
1480	pci_power_t target_state = pci_target_state(dev);
1481	int error;
1482
1483	if (target_state == PCI_POWER_ERROR)
1484		return -EIO;
1485
1486	pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
1487
1488	error = pci_set_power_state(dev, target_state);
1489
1490	if (error)
1491		pci_enable_wake(dev, target_state, false);
1492
1493	return error;
1494}
1495
1496/**
1497 * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
1498 * @dev: Device to handle.
1499 *
1500 * Disable device's system wake-up capability and put it into D0.
1501 */
1502int pci_back_from_sleep(struct pci_dev *dev)
1503{
1504	pci_enable_wake(dev, PCI_D0, false);
1505	return pci_set_power_state(dev, PCI_D0);
1506}
1507
1508/**
1509 * pci_finish_runtime_suspend - Carry out PCI-specific part of runtime suspend.
1510 * @dev: PCI device being suspended.
1511 *
1512 * Prepare @dev to generate wake-up events at run time and put it into a low
1513 * power state.
1514 */
1515int pci_finish_runtime_suspend(struct pci_dev *dev)
1516{
1517	pci_power_t target_state = pci_target_state(dev);
1518	int error;
1519
1520	if (target_state == PCI_POWER_ERROR)
1521		return -EIO;
1522
1523	__pci_enable_wake(dev, target_state, true, pci_dev_run_wake(dev));
1524
1525	error = pci_set_power_state(dev, target_state);
1526
1527	if (error)
1528		__pci_enable_wake(dev, target_state, true, false);
1529
1530	return error;
1531}
1532
1533/**
1534 * pci_dev_run_wake - Check if device can generate run-time wake-up events.
1535 * @dev: Device to check.
1536 *
1537 * Return true if the device itself is cabable of generating wake-up events
1538 * (through the platform or using the native PCIe PME) or if the device supports
1539 * PME and one of its upstream bridges can generate wake-up events.
1540 */
1541bool pci_dev_run_wake(struct pci_dev *dev)
1542{
1543	struct pci_bus *bus = dev->bus;
1544
1545	if (device_run_wake(&dev->dev))
1546		return true;
1547
1548	if (!dev->pme_support)
1549		return false;
1550
1551	while (bus->parent) {
1552		struct pci_dev *bridge = bus->self;
1553
1554		if (device_run_wake(&bridge->dev))
1555			return true;
1556
1557		bus = bus->parent;
1558	}
1559
1560	/* We have reached the root bus. */
1561	if (bus->bridge)
1562		return device_run_wake(bus->bridge);
1563
1564	return false;
1565}
1566EXPORT_SYMBOL_GPL(pci_dev_run_wake);
1567
1568/**
1569 * pci_pm_init - Initialize PM functions of given PCI device
1570 * @dev: PCI device to handle.
1571 */
1572void pci_pm_init(struct pci_dev *dev)
1573{
1574	int pm;
1575	u16 pmc;
1576
1577	pm_runtime_forbid(&dev->dev);
1578	device_enable_async_suspend(&dev->dev);
1579	dev->wakeup_prepared = false;
1580
1581	dev->pm_cap = 0;
1582
1583	/* find PCI PM capability in list */
1584	pm = pci_find_capability(dev, PCI_CAP_ID_PM);
1585	if (!pm)
1586		return;
1587	/* Check device's ability to generate PME# */
1588	pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
1589
1590	if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
1591		dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
1592			pmc & PCI_PM_CAP_VER_MASK);
1593		return;
1594	}
1595
1596	dev->pm_cap = pm;
1597	dev->d3_delay = PCI_PM_D3_WAIT;
1598
1599	dev->d1_support = false;
1600	dev->d2_support = false;
1601	if (!pci_no_d1d2(dev)) {
1602		if (pmc & PCI_PM_CAP_D1)
1603			dev->d1_support = true;
1604		if (pmc & PCI_PM_CAP_D2)
1605			dev->d2_support = true;
1606
1607		if (dev->d1_support || dev->d2_support)
1608			dev_printk(KERN_DEBUG, &dev->dev, "supports%s%s\n",
1609				   dev->d1_support ? " D1" : "",
1610				   dev->d2_support ? " D2" : "");
1611	}
1612
1613	pmc &= PCI_PM_CAP_PME_MASK;
1614	if (pmc) {
1615		dev_printk(KERN_DEBUG, &dev->dev,
1616			 "PME# supported from%s%s%s%s%s\n",
1617			 (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
1618			 (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
1619			 (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
1620			 (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
1621			 (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
1622		dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
1623		/*
1624		 * Make device's PM flags reflect the wake-up capability, but
1625		 * let the user space enable it to wake up the system as needed.
1626		 */
1627		device_set_wakeup_capable(&dev->dev, true);
1628		/* Disable the PME# generation functionality */
1629		pci_pme_active(dev, false);
1630	} else {
1631		dev->pme_support = 0;
1632	}
1633}
1634
1635/**
1636 * platform_pci_wakeup_init - init platform wakeup if present
1637 * @dev: PCI device
1638 *
1639 * Some devices don't have PCI PM caps but can still generate wakeup
1640 * events through platform methods (like ACPI events).  If @dev supports
1641 * platform wakeup events, set the device flag to indicate as much.  This
1642 * may be redundant if the device also supports PCI PM caps, but double
1643 * initialization should be safe in that case.
1644 */
1645void platform_pci_wakeup_init(struct pci_dev *dev)
1646{
1647	if (!platform_pci_can_wakeup(dev))
1648		return;
1649
1650	device_set_wakeup_capable(&dev->dev, true);
1651	platform_pci_sleep_wake(dev, false);
1652}
1653
1654/**
1655 * pci_add_save_buffer - allocate buffer for saving given capability registers
1656 * @dev: the PCI device
1657 * @cap: the capability to allocate the buffer for
1658 * @size: requested size of the buffer
1659 */
1660static int pci_add_cap_save_buffer(
1661	struct pci_dev *dev, char cap, unsigned int size)
1662{
1663	int pos;
1664	struct pci_cap_saved_state *save_state;
1665
1666	pos = pci_find_capability(dev, cap);
1667	if (pos <= 0)
1668		return 0;
1669
1670	save_state = kzalloc(sizeof(*save_state) + size, GFP_KERNEL);
1671	if (!save_state)
1672		return -ENOMEM;
1673
1674	save_state->cap_nr = cap;
1675	pci_add_saved_cap(dev, save_state);
1676
1677	return 0;
1678}
1679
1680/**
1681 * pci_allocate_cap_save_buffers - allocate buffers for saving capabilities
1682 * @dev: the PCI device
1683 */
1684void pci_allocate_cap_save_buffers(struct pci_dev *dev)
1685{
1686	int error;
1687
1688	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_EXP,
1689					PCI_EXP_SAVE_REGS * sizeof(u16));
1690	if (error)
1691		dev_err(&dev->dev,
1692			"unable to preallocate PCI Express save buffer\n");
1693
1694	error = pci_add_cap_save_buffer(dev, PCI_CAP_ID_PCIX, sizeof(u16));
1695	if (error)
1696		dev_err(&dev->dev,
1697			"unable to preallocate PCI-X save buffer\n");
1698}
1699
1700/**
1701 * pci_enable_ari - enable ARI forwarding if hardware support it
1702 * @dev: the PCI device
1703 */
1704void pci_enable_ari(struct pci_dev *dev)
1705{
1706	int pos;
1707	u32 cap;
1708	u16 ctrl;
1709	struct pci_dev *bridge;
1710
1711	if (!pci_is_pcie(dev) || dev->devfn)
1712		return;
1713
1714	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1715	if (!pos)
1716		return;
1717
1718	bridge = dev->bus->self;
1719	if (!bridge || !pci_is_pcie(bridge))
1720		return;
1721
1722	pos = pci_pcie_cap(bridge);
1723	if (!pos)
1724		return;
1725
1726	pci_read_config_dword(bridge, pos + PCI_EXP_DEVCAP2, &cap);
1727	if (!(cap & PCI_EXP_DEVCAP2_ARI))
1728		return;
1729
1730	pci_read_config_word(bridge, pos + PCI_EXP_DEVCTL2, &ctrl);
1731	ctrl |= PCI_EXP_DEVCTL2_ARI;
1732	pci_write_config_word(bridge, pos + PCI_EXP_DEVCTL2, ctrl);
1733
1734	bridge->ari_enabled = 1;
1735}
1736
1737static int pci_acs_enable;
1738
1739/**
1740 * pci_request_acs - ask for ACS to be enabled if supported
1741 */
1742void pci_request_acs(void)
1743{
1744	pci_acs_enable = 1;
1745}
1746
1747/**
1748 * pci_enable_acs - enable ACS if hardware support it
1749 * @dev: the PCI device
1750 */
1751void pci_enable_acs(struct pci_dev *dev)
1752{
1753	int pos;
1754	u16 cap;
1755	u16 ctrl;
1756
1757	if (!pci_acs_enable)
1758		return;
1759
1760	if (!pci_is_pcie(dev))
1761		return;
1762
1763	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
1764	if (!pos)
1765		return;
1766
1767	pci_read_config_word(dev, pos + PCI_ACS_CAP, &cap);
1768	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
1769
1770	/* Source Validation */
1771	ctrl |= (cap & PCI_ACS_SV);
1772
1773	/* P2P Request Redirect */
1774	ctrl |= (cap & PCI_ACS_RR);
1775
1776	/* P2P Completion Redirect */
1777	ctrl |= (cap & PCI_ACS_CR);
1778
1779	/* Upstream Forwarding */
1780	ctrl |= (cap & PCI_ACS_UF);
1781
1782	pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
1783}
1784
1785/**
1786 * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
1787 * @dev: the PCI device
1788 * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTD, 4=INTD)
1789 *
1790 * Perform INTx swizzling for a device behind one level of bridge.  This is
1791 * required by section 9.1 of the PCI-to-PCI bridge specification for devices
1792 * behind bridges on add-in cards.  For devices with ARI enabled, the slot
1793 * number is always 0 (see the Implementation Note in section 2.2.8.1 of
1794 * the PCI Express Base Specification, Revision 2.1)
1795 */
1796u8 pci_swizzle_interrupt_pin(struct pci_dev *dev, u8 pin)
1797{
1798	int slot;
1799
1800	if (pci_ari_enabled(dev->bus))
1801		slot = 0;
1802	else
1803		slot = PCI_SLOT(dev->devfn);
1804
1805	return (((pin - 1) + slot) % 4) + 1;
1806}
1807
1808int
1809pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
1810{
1811	u8 pin;
1812
1813	pin = dev->pin;
1814	if (!pin)
1815		return -1;
1816
1817	while (!pci_is_root_bus(dev->bus)) {
1818		pin = pci_swizzle_interrupt_pin(dev, pin);
1819		dev = dev->bus->self;
1820	}
1821	*bridge = dev;
1822	return pin;
1823}
1824
1825/**
1826 * pci_common_swizzle - swizzle INTx all the way to root bridge
1827 * @dev: the PCI device
1828 * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
1829 *
1830 * Perform INTx swizzling for a device.  This traverses through all PCI-to-PCI
1831 * bridges all the way up to a PCI root bus.
1832 */
1833u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
1834{
1835	u8 pin = *pinp;
1836
1837	while (!pci_is_root_bus(dev->bus)) {
1838		pin = pci_swizzle_interrupt_pin(dev, pin);
1839		dev = dev->bus->self;
1840	}
1841	*pinp = pin;
1842	return PCI_SLOT(dev->devfn);
1843}
1844
1845/**
1846 *	pci_release_region - Release a PCI bar
1847 *	@pdev: PCI device whose resources were previously reserved by pci_request_region
1848 *	@bar: BAR to release
1849 *
1850 *	Releases the PCI I/O and memory resources previously reserved by a
1851 *	successful call to pci_request_region.  Call this function only
1852 *	after all use of the PCI regions has ceased.
1853 */
1854void pci_release_region(struct pci_dev *pdev, int bar)
1855{
1856	struct pci_devres *dr;
1857
1858	if (pci_resource_len(pdev, bar) == 0)
1859		return;
1860	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
1861		release_region(pci_resource_start(pdev, bar),
1862				pci_resource_len(pdev, bar));
1863	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
1864		release_mem_region(pci_resource_start(pdev, bar),
1865				pci_resource_len(pdev, bar));
1866
1867	dr = find_pci_dr(pdev);
1868	if (dr)
1869		dr->region_mask &= ~(1 << bar);
1870}
1871
1872/**
1873 *	__pci_request_region - Reserved PCI I/O and memory resource
1874 *	@pdev: PCI device whose resources are to be reserved
1875 *	@bar: BAR to be reserved
1876 *	@res_name: Name to be associated with resource.
1877 *	@exclusive: whether the region access is exclusive or not
1878 *
1879 *	Mark the PCI region associated with PCI device @pdev BR @bar as
1880 *	being reserved by owner @res_name.  Do not access any
1881 *	address inside the PCI regions unless this call returns
1882 *	successfully.
1883 *
1884 *	If @exclusive is set, then the region is marked so that userspace
1885 *	is explicitly not allowed to map the resource via /dev/mem or
1886 * 	sysfs MMIO access.
1887 *
1888 *	Returns 0 on success, or %EBUSY on error.  A warning
1889 *	message is also printed on failure.
1890 */
1891static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
1892									int exclusive)
1893{
1894	struct pci_devres *dr;
1895
1896	if (pci_resource_len(pdev, bar) == 0)
1897		return 0;
1898
1899	if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
1900		if (!request_region(pci_resource_start(pdev, bar),
1901			    pci_resource_len(pdev, bar), res_name))
1902			goto err_out;
1903	}
1904	else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
1905		if (!__request_mem_region(pci_resource_start(pdev, bar),
1906					pci_resource_len(pdev, bar), res_name,
1907					exclusive))
1908			goto err_out;
1909	}
1910
1911	dr = find_pci_dr(pdev);
1912	if (dr)
1913		dr->region_mask |= 1 << bar;
1914
1915	return 0;
1916
1917err_out:
1918	dev_warn(&pdev->dev, "BAR %d: can't reserve %pR\n", bar,
1919		 &pdev->resource[bar]);
1920	return -EBUSY;
1921}
1922
1923/**
1924 *	pci_request_region - Reserve PCI I/O and memory resource
1925 *	@pdev: PCI device whose resources are to be reserved
1926 *	@bar: BAR to be reserved
1927 *	@res_name: Name to be associated with resource
1928 *
1929 *	Mark the PCI region associated with PCI device @pdev BAR @bar as
1930 *	being reserved by owner @res_name.  Do not access any
1931 *	address inside the PCI regions unless this call returns
1932 *	successfully.
1933 *
1934 *	Returns 0 on success, or %EBUSY on error.  A warning
1935 *	message is also printed on failure.
1936 */
1937int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
1938{
1939	return __pci_request_region(pdev, bar, res_name, 0);
1940}
1941
1942/**
1943 *	pci_request_region_exclusive - Reserved PCI I/O and memory resource
1944 *	@pdev: PCI device whose resources are to be reserved
1945 *	@bar: BAR to be reserved
1946 *	@res_name: Name to be associated with resource.
1947 *
1948 *	Mark the PCI region associated with PCI device @pdev BR @bar as
1949 *	being reserved by owner @res_name.  Do not access any
1950 *	address inside the PCI regions unless this call returns
1951 *	successfully.
1952 *
1953 *	Returns 0 on success, or %EBUSY on error.  A warning
1954 *	message is also printed on failure.
1955 *
1956 *	The key difference that _exclusive makes it that userspace is
1957 *	explicitly not allowed to map the resource via /dev/mem or
1958 * 	sysfs.
1959 */
1960int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name)
1961{
1962	return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
1963}
1964/**
1965 * pci_release_selected_regions - Release selected PCI I/O and memory resources
1966 * @pdev: PCI device whose resources were previously reserved
1967 * @bars: Bitmask of BARs to be released
1968 *
1969 * Release selected PCI I/O and memory resources previously reserved.
1970 * Call this function only after all use of the PCI regions has ceased.
1971 */
1972void pci_release_selected_regions(struct pci_dev *pdev, int bars)
1973{
1974	int i;
1975
1976	for (i = 0; i < 6; i++)
1977		if (bars & (1 << i))
1978			pci_release_region(pdev, i);
1979}
1980
1981int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
1982				 const char *res_name, int excl)
1983{
1984	int i;
1985
1986	for (i = 0; i < 6; i++)
1987		if (bars & (1 << i))
1988			if (__pci_request_region(pdev, i, res_name, excl))
1989				goto err_out;
1990	return 0;
1991
1992err_out:
1993	while(--i >= 0)
1994		if (bars & (1 << i))
1995			pci_release_region(pdev, i);
1996
1997	return -EBUSY;
1998}
1999
2000
2001/**
2002 * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
2003 * @pdev: PCI device whose resources are to be reserved
2004 * @bars: Bitmask of BARs to be requested
2005 * @res_name: Name to be associated with resource
2006 */
2007int pci_request_selected_regions(struct pci_dev *pdev, int bars,
2008				 const char *res_name)
2009{
2010	return __pci_request_selected_regions(pdev, bars, res_name, 0);
2011}
2012
2013int pci_request_selected_regions_exclusive(struct pci_dev *pdev,
2014				 int bars, const char *res_name)
2015{
2016	return __pci_request_selected_regions(pdev, bars, res_name,
2017			IORESOURCE_EXCLUSIVE);
2018}
2019
2020/**
2021 *	pci_release_regions - Release reserved PCI I/O and memory resources
2022 *	@pdev: PCI device whose resources were previously reserved by pci_request_regions
2023 *
2024 *	Releases all PCI I/O and memory resources previously reserved by a
2025 *	successful call to pci_request_regions.  Call this function only
2026 *	after all use of the PCI regions has ceased.
2027 */
2028
2029void pci_release_regions(struct pci_dev *pdev)
2030{
2031	pci_release_selected_regions(pdev, (1 << 6) - 1);
2032}
2033
2034/**
2035 *	pci_request_regions - Reserved PCI I/O and memory resources
2036 *	@pdev: PCI device whose resources are to be reserved
2037 *	@res_name: Name to be associated with resource.
2038 *
2039 *	Mark all PCI regions associated with PCI device @pdev as
2040 *	being reserved by owner @res_name.  Do not access any
2041 *	address inside the PCI regions unless this call returns
2042 *	successfully.
2043 *
2044 *	Returns 0 on success, or %EBUSY on error.  A warning
2045 *	message is also printed on failure.
2046 */
2047int pci_request_regions(struct pci_dev *pdev, const char *res_name)
2048{
2049	return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
2050}
2051
2052/**
2053 *	pci_request_regions_exclusive - Reserved PCI I/O and memory resources
2054 *	@pdev: PCI device whose resources are to be reserved
2055 *	@res_name: Name to be associated with resource.
2056 *
2057 *	Mark all PCI regions associated with PCI device @pdev as
2058 *	being reserved by owner @res_name.  Do not access any
2059 *	address inside the PCI regions unless this call returns
2060 *	successfully.
2061 *
2062 *	pci_request_regions_exclusive() will mark the region so that
2063 * 	/dev/mem and the sysfs MMIO access will not be allowed.
2064 *
2065 *	Returns 0 on success, or %EBUSY on error.  A warning
2066 *	message is also printed on failure.
2067 */
2068int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
2069{
2070	return pci_request_selected_regions_exclusive(pdev,
2071					((1 << 6) - 1), res_name);
2072}
2073
2074static void __pci_set_master(struct pci_dev *dev, bool enable)
2075{
2076	u16 old_cmd, cmd;
2077
2078	pci_read_config_word(dev, PCI_COMMAND, &old_cmd);
2079	if (enable)
2080		cmd = old_cmd | PCI_COMMAND_MASTER;
2081	else
2082		cmd = old_cmd & ~PCI_COMMAND_MASTER;
2083	if (cmd != old_cmd) {
2084		dev_dbg(&dev->dev, "%s bus mastering\n",
2085			enable ? "enabling" : "disabling");
2086		pci_write_config_word(dev, PCI_COMMAND, cmd);
2087	}
2088	dev->is_busmaster = enable;
2089}
2090
2091/**
2092 * pci_set_master - enables bus-mastering for device dev
2093 * @dev: the PCI device to enable
2094 *
2095 * Enables bus-mastering on the device and calls pcibios_set_master()
2096 * to do the needed arch specific settings.
2097 */
2098void pci_set_master(struct pci_dev *dev)
2099{
2100	__pci_set_master(dev, true);
2101	pcibios_set_master(dev);
2102}
2103
2104/**
2105 * pci_clear_master - disables bus-mastering for device dev
2106 * @dev: the PCI device to disable
2107 */
2108void pci_clear_master(struct pci_dev *dev)
2109{
2110	__pci_set_master(dev, false);
2111}
2112
2113/**
2114 * pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
2115 * @dev: the PCI device for which MWI is to be enabled
2116 *
2117 * Helper function for pci_set_mwi.
2118 * Originally copied from drivers/net/acenic.c.
2119 * Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
2120 *
2121 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2122 */
2123int pci_set_cacheline_size(struct pci_dev *dev)
2124{
2125	u8 cacheline_size;
2126
2127	if (!pci_cache_line_size)
2128		return -EINVAL;
2129
2130	/* Validate current setting: the PCI_CACHE_LINE_SIZE must be
2131	   equal to or multiple of the right value. */
2132	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2133	if (cacheline_size >= pci_cache_line_size &&
2134	    (cacheline_size % pci_cache_line_size) == 0)
2135		return 0;
2136
2137	/* Write the correct value. */
2138	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
2139	/* Read it back. */
2140	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
2141	if (cacheline_size == pci_cache_line_size)
2142		return 0;
2143
2144	dev_printk(KERN_DEBUG, &dev->dev, "cache line size of %d is not "
2145		   "supported\n", pci_cache_line_size << 2);
2146
2147	return -EINVAL;
2148}
2149EXPORT_SYMBOL_GPL(pci_set_cacheline_size);
2150
2151#ifdef PCI_DISABLE_MWI
2152int pci_set_mwi(struct pci_dev *dev)
2153{
2154	return 0;
2155}
2156
2157int pci_try_set_mwi(struct pci_dev *dev)
2158{
2159	return 0;
2160}
2161
2162void pci_clear_mwi(struct pci_dev *dev)
2163{
2164}
2165
2166#else
2167
2168/**
2169 * pci_set_mwi - enables memory-write-invalidate PCI transaction
2170 * @dev: the PCI device for which MWI is enabled
2171 *
2172 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2173 *
2174 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2175 */
2176int
2177pci_set_mwi(struct pci_dev *dev)
2178{
2179	int rc;
2180	u16 cmd;
2181
2182	rc = pci_set_cacheline_size(dev);
2183	if (rc)
2184		return rc;
2185
2186	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2187	if (! (cmd & PCI_COMMAND_INVALIDATE)) {
2188		dev_dbg(&dev->dev, "enabling Mem-Wr-Inval\n");
2189		cmd |= PCI_COMMAND_INVALIDATE;
2190		pci_write_config_word(dev, PCI_COMMAND, cmd);
2191	}
2192
2193	return 0;
2194}
2195
2196/**
2197 * pci_try_set_mwi - enables memory-write-invalidate PCI transaction
2198 * @dev: the PCI device for which MWI is enabled
2199 *
2200 * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND.
2201 * Callers are not required to check the return value.
2202 *
2203 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
2204 */
2205int pci_try_set_mwi(struct pci_dev *dev)
2206{
2207	int rc = pci_set_mwi(dev);
2208	return rc;
2209}
2210
2211/**
2212 * pci_clear_mwi - disables Memory-Write-Invalidate for device dev
2213 * @dev: the PCI device to disable
2214 *
2215 * Disables PCI Memory-Write-Invalidate transaction on the device
2216 */
2217void
2218pci_clear_mwi(struct pci_dev *dev)
2219{
2220	u16 cmd;
2221
2222	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2223	if (cmd & PCI_COMMAND_INVALIDATE) {
2224		cmd &= ~PCI_COMMAND_INVALIDATE;
2225		pci_write_config_word(dev, PCI_COMMAND, cmd);
2226	}
2227}
2228#endif /* ! PCI_DISABLE_MWI */
2229
2230/**
2231 * pci_intx - enables/disables PCI INTx for device dev
2232 * @pdev: the PCI device to operate on
2233 * @enable: boolean: whether to enable or disable PCI INTx
2234 *
2235 * Enables/disables PCI INTx for device dev
2236 */
2237void
2238pci_intx(struct pci_dev *pdev, int enable)
2239{
2240	u16 pci_command, new;
2241
2242	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
2243
2244	if (enable) {
2245		new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
2246	} else {
2247		new = pci_command | PCI_COMMAND_INTX_DISABLE;
2248	}
2249
2250	if (new != pci_command) {
2251		struct pci_devres *dr;
2252
2253		pci_write_config_word(pdev, PCI_COMMAND, new);
2254
2255		dr = find_pci_dr(pdev);
2256		if (dr && !dr->restore_intx) {
2257			dr->restore_intx = 1;
2258			dr->orig_intx = !enable;
2259		}
2260	}
2261}
2262
2263/**
2264 * pci_msi_off - disables any msi or msix capabilities
2265 * @dev: the PCI device to operate on
2266 *
2267 * If you want to use msi see pci_enable_msi and friends.
2268 * This is a lower level primitive that allows us to disable
2269 * msi operation at the device level.
2270 */
2271void pci_msi_off(struct pci_dev *dev)
2272{
2273	int pos;
2274	u16 control;
2275
2276	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
2277	if (pos) {
2278		pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
2279		control &= ~PCI_MSI_FLAGS_ENABLE;
2280		pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
2281	}
2282	pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
2283	if (pos) {
2284		pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
2285		control &= ~PCI_MSIX_FLAGS_ENABLE;
2286		pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
2287	}
2288}
2289EXPORT_SYMBOL_GPL(pci_msi_off);
2290
2291int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size)
2292{
2293	return dma_set_max_seg_size(&dev->dev, size);
2294}
2295EXPORT_SYMBOL(pci_set_dma_max_seg_size);
2296
2297int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask)
2298{
2299	return dma_set_seg_boundary(&dev->dev, mask);
2300}
2301EXPORT_SYMBOL(pci_set_dma_seg_boundary);
2302
2303static int pcie_flr(struct pci_dev *dev, int probe)
2304{
2305	int i;
2306	int pos;
2307	u32 cap;
2308	u16 status, control;
2309
2310	pos = pci_pcie_cap(dev);
2311	if (!pos)
2312		return -ENOTTY;
2313
2314	pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP, &cap);
2315	if (!(cap & PCI_EXP_DEVCAP_FLR))
2316		return -ENOTTY;
2317
2318	if (probe)
2319		return 0;
2320
2321	/* Wait for Transaction Pending bit clean */
2322	for (i = 0; i < 4; i++) {
2323		if (i)
2324			msleep((1 << (i - 1)) * 100);
2325
2326		pci_read_config_word(dev, pos + PCI_EXP_DEVSTA, &status);
2327		if (!(status & PCI_EXP_DEVSTA_TRPND))
2328			goto clear;
2329	}
2330
2331	dev_err(&dev->dev, "transaction is not cleared; "
2332			"proceeding with reset anyway\n");
2333
2334clear:
2335	pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &control);
2336	control |= PCI_EXP_DEVCTL_BCR_FLR;
2337	pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, control);
2338
2339	msleep(100);
2340
2341	return 0;
2342}
2343
2344static int pci_af_flr(struct pci_dev *dev, int probe)
2345{
2346	int i;
2347	int pos;
2348	u8 cap;
2349	u8 status;
2350
2351	pos = pci_find_capability(dev, PCI_CAP_ID_AF);
2352	if (!pos)
2353		return -ENOTTY;
2354
2355	pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
2356	if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
2357		return -ENOTTY;
2358
2359	if (probe)
2360		return 0;
2361
2362	/* Wait for Transaction Pending bit clean */
2363	for (i = 0; i < 4; i++) {
2364		if (i)
2365			msleep((1 << (i - 1)) * 100);
2366
2367		pci_read_config_byte(dev, pos + PCI_AF_STATUS, &status);
2368		if (!(status & PCI_AF_STATUS_TP))
2369			goto clear;
2370	}
2371
2372	dev_err(&dev->dev, "transaction is not cleared; "
2373			"proceeding with reset anyway\n");
2374
2375clear:
2376	pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR);
2377	msleep(100);
2378
2379	return 0;
2380}
2381
2382static int pci_pm_reset(struct pci_dev *dev, int probe)
2383{
2384	u16 csr;
2385
2386	if (!dev->pm_cap)
2387		return -ENOTTY;
2388
2389	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &csr);
2390	if (csr & PCI_PM_CTRL_NO_SOFT_RESET)
2391		return -ENOTTY;
2392
2393	if (probe)
2394		return 0;
2395
2396	if (dev->current_state != PCI_D0)
2397		return -EINVAL;
2398
2399	csr &= ~PCI_PM_CTRL_STATE_MASK;
2400	csr |= PCI_D3hot;
2401	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
2402	pci_dev_d3_sleep(dev);
2403
2404	csr &= ~PCI_PM_CTRL_STATE_MASK;
2405	csr |= PCI_D0;
2406	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
2407	pci_dev_d3_sleep(dev);
2408
2409	return 0;
2410}
2411
2412static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
2413{
2414	u16 ctrl;
2415	struct pci_dev *pdev;
2416
2417	if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self)
2418		return -ENOTTY;
2419
2420	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
2421		if (pdev != dev)
2422			return -ENOTTY;
2423
2424	if (probe)
2425		return 0;
2426
2427	pci_read_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, &ctrl);
2428	ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
2429	pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
2430	msleep(100);
2431
2432	ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
2433	pci_write_config_word(dev->bus->self, PCI_BRIDGE_CONTROL, ctrl);
2434	msleep(100);
2435
2436	return 0;
2437}
2438
2439static int pci_dev_reset(struct pci_dev *dev, int probe)
2440{
2441	int rc;
2442
2443	might_sleep();
2444
2445	if (!probe) {
2446		pci_block_user_cfg_access(dev);
2447		/* block PM suspend, driver probe, etc. */
2448		device_lock(&dev->dev);
2449	}
2450
2451	rc = pci_dev_specific_reset(dev, probe);
2452	if (rc != -ENOTTY)
2453		goto done;
2454
2455	rc = pcie_flr(dev, probe);
2456	if (rc != -ENOTTY)
2457		goto done;
2458
2459	rc = pci_af_flr(dev, probe);
2460	if (rc != -ENOTTY)
2461		goto done;
2462
2463	rc = pci_pm_reset(dev, probe);
2464	if (rc != -ENOTTY)
2465		goto done;
2466
2467	rc = pci_parent_bus_reset(dev, probe);
2468done:
2469	if (!probe) {
2470		device_unlock(&dev->dev);
2471		pci_unblock_user_cfg_access(dev);
2472	}
2473
2474	return rc;
2475}
2476
2477/**
2478 * __pci_reset_function - reset a PCI device function
2479 * @dev: PCI device to reset
2480 *
2481 * Some devices allow an individual function to be reset without affecting
2482 * other functions in the same device.  The PCI device must be responsive
2483 * to PCI config space in order to use this function.
2484 *
2485 * The device function is presumed to be unused when this function is called.
2486 * Resetting the device will make the contents of PCI configuration space
2487 * random, so any caller of this must be prepared to reinitialise the
2488 * device including MSI, bus mastering, BARs, decoding IO and memory spaces,
2489 * etc.
2490 *
2491 * Returns 0 if the device function was successfully reset or negative if the
2492 * device doesn't support resetting a single function.
2493 */
2494int __pci_reset_function(struct pci_dev *dev)
2495{
2496	return pci_dev_reset(dev, 0);
2497}
2498EXPORT_SYMBOL_GPL(__pci_reset_function);
2499
2500/**
2501 * pci_probe_reset_function - check whether the device can be safely reset
2502 * @dev: PCI device to reset
2503 *
2504 * Some devices allow an individual function to be reset without affecting
2505 * other functions in the same device.  The PCI device must be responsive
2506 * to PCI config space in order to use this function.
2507 *
2508 * Returns 0 if the device function can be reset or negative if the
2509 * device doesn't support resetting a single function.
2510 */
2511int pci_probe_reset_function(struct pci_dev *dev)
2512{
2513	return pci_dev_reset(dev, 1);
2514}
2515
2516/**
2517 * pci_reset_function - quiesce and reset a PCI device function
2518 * @dev: PCI device to reset
2519 *
2520 * Some devices allow an individual function to be reset without affecting
2521 * other functions in the same device.  The PCI device must be responsive
2522 * to PCI config space in order to use this function.
2523 *
2524 * This function does not just reset the PCI portion of a device, but
2525 * clears all the state associated with the device.  This function differs
2526 * from __pci_reset_function in that it saves and restores device state
2527 * over the reset.
2528 *
2529 * Returns 0 if the device function was successfully reset or negative if the
2530 * device doesn't support resetting a single function.
2531 */
2532int pci_reset_function(struct pci_dev *dev)
2533{
2534	int rc;
2535
2536	rc = pci_dev_reset(dev, 1);
2537	if (rc)
2538		return rc;
2539
2540	pci_save_state(dev);
2541
2542	/*
2543	 * both INTx and MSI are disabled after the Interrupt Disable bit
2544	 * is set and the Bus Master bit is cleared.
2545	 */
2546	pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
2547
2548	rc = pci_dev_reset(dev, 0);
2549
2550	pci_restore_state(dev);
2551
2552	return rc;
2553}
2554EXPORT_SYMBOL_GPL(pci_reset_function);
2555
2556/**
2557 * pcix_get_max_mmrbc - get PCI-X maximum designed memory read byte count
2558 * @dev: PCI device to query
2559 *
2560 * Returns mmrbc: maximum designed memory read count in bytes
2561 *    or appropriate error value.
2562 */
2563int pcix_get_max_mmrbc(struct pci_dev *dev)
2564{
2565	int cap;
2566	u32 stat;
2567
2568	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2569	if (!cap)
2570		return -EINVAL;
2571
2572	if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
2573		return -EINVAL;
2574
2575	return 512 << ((stat & PCI_X_STATUS_MAX_READ) >> 21);
2576}
2577EXPORT_SYMBOL(pcix_get_max_mmrbc);
2578
2579/**
2580 * pcix_get_mmrbc - get PCI-X maximum memory read byte count
2581 * @dev: PCI device to query
2582 *
2583 * Returns mmrbc: maximum memory read count in bytes
2584 *    or appropriate error value.
2585 */
2586int pcix_get_mmrbc(struct pci_dev *dev)
2587{
2588	int cap;
2589	u16 cmd;
2590
2591	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2592	if (!cap)
2593		return -EINVAL;
2594
2595	if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
2596		return -EINVAL;
2597
2598	return 512 << ((cmd & PCI_X_CMD_MAX_READ) >> 2);
2599}
2600EXPORT_SYMBOL(pcix_get_mmrbc);
2601
2602/**
2603 * pcix_set_mmrbc - set PCI-X maximum memory read byte count
2604 * @dev: PCI device to query
2605 * @mmrbc: maximum memory read count in bytes
2606 *    valid values are 512, 1024, 2048, 4096
2607 *
2608 * If possible sets maximum memory read byte count, some bridges have erratas
2609 * that prevent this.
2610 */
2611int pcix_set_mmrbc(struct pci_dev *dev, int mmrbc)
2612{
2613	int cap;
2614	u32 stat, v, o;
2615	u16 cmd;
2616
2617	if (mmrbc < 512 || mmrbc > 4096 || !is_power_of_2(mmrbc))
2618		return -EINVAL;
2619
2620	v = ffs(mmrbc) - 10;
2621
2622	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
2623	if (!cap)
2624		return -EINVAL;
2625
2626	if (pci_read_config_dword(dev, cap + PCI_X_STATUS, &stat))
2627		return -EINVAL;
2628
2629	if (v > (stat & PCI_X_STATUS_MAX_READ) >> 21)
2630		return -E2BIG;
2631
2632	if (pci_read_config_word(dev, cap + PCI_X_CMD, &cmd))
2633		return -EINVAL;
2634
2635	o = (cmd & PCI_X_CMD_MAX_READ) >> 2;
2636	if (o != v) {
2637		if (v > o && dev->bus &&
2638		   (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_MMRBC))
2639			return -EIO;
2640
2641		cmd &= ~PCI_X_CMD_MAX_READ;
2642		cmd |= v << 2;
2643		if (pci_write_config_word(dev, cap + PCI_X_CMD, cmd))
2644			return -EIO;
2645	}
2646	return 0;
2647}
2648EXPORT_SYMBOL(pcix_set_mmrbc);
2649
2650/**
2651 * pcie_get_readrq - get PCI Express read request size
2652 * @dev: PCI device to query
2653 *
2654 * Returns maximum memory read request in bytes
2655 *    or appropriate error value.
2656 */
2657int pcie_get_readrq(struct pci_dev *dev)
2658{
2659	int ret, cap;
2660	u16 ctl;
2661
2662	cap = pci_pcie_cap(dev);
2663	if (!cap)
2664		return -EINVAL;
2665
2666	ret = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
2667	if (!ret)
2668	ret = 128 << ((ctl & PCI_EXP_DEVCTL_READRQ) >> 12);
2669
2670	return ret;
2671}
2672EXPORT_SYMBOL(pcie_get_readrq);
2673
2674/**
2675 * pcie_set_readrq - set PCI Express maximum memory read request
2676 * @dev: PCI device to query
2677 * @rq: maximum memory read count in bytes
2678 *    valid values are 128, 256, 512, 1024, 2048, 4096
2679 *
2680 * If possible sets maximum read byte count
2681 */
2682int pcie_set_readrq(struct pci_dev *dev, int rq)
2683{
2684	int cap, err = -EINVAL;
2685	u16 ctl, v;
2686
2687	if (rq < 128 || rq > 4096 || !is_power_of_2(rq))
2688		goto out;
2689
2690	v = (ffs(rq) - 8) << 12;
2691
2692	cap = pci_pcie_cap(dev);
2693	if (!cap)
2694		goto out;
2695
2696	err = pci_read_config_word(dev, cap + PCI_EXP_DEVCTL, &ctl);
2697	if (err)
2698		goto out;
2699
2700	if ((ctl & PCI_EXP_DEVCTL_READRQ) != v) {
2701		ctl &= ~PCI_EXP_DEVCTL_READRQ;
2702		ctl |= v;
2703		err = pci_write_config_dword(dev, cap + PCI_EXP_DEVCTL, ctl);
2704	}
2705
2706out:
2707	return err;
2708}
2709EXPORT_SYMBOL(pcie_set_readrq);
2710
2711/**
2712 * pci_select_bars - Make BAR mask from the type of resource
2713 * @dev: the PCI device for which BAR mask is made
2714 * @flags: resource type mask to be selected
2715 *
2716 * This helper routine makes bar mask from the type of resource.
2717 */
2718int pci_select_bars(struct pci_dev *dev, unsigned long flags)
2719{
2720	int i, bars = 0;
2721	for (i = 0; i < PCI_NUM_RESOURCES; i++)
2722		if (pci_resource_flags(dev, i) & flags)
2723			bars |= (1 << i);
2724	return bars;
2725}
2726
2727/**
2728 * pci_resource_bar - get position of the BAR associated with a resource
2729 * @dev: the PCI device
2730 * @resno: the resource number
2731 * @type: the BAR type to be filled in
2732 *
2733 * Returns BAR position in config space, or 0 if the BAR is invalid.
2734 */
2735int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type)
2736{
2737	int reg;
2738
2739	if (resno < PCI_ROM_RESOURCE) {
2740		*type = pci_bar_unknown;
2741		return PCI_BASE_ADDRESS_0 + 4 * resno;
2742	} else if (resno == PCI_ROM_RESOURCE) {
2743		*type = pci_bar_mem32;
2744		return dev->rom_base_reg;
2745	} else if (resno < PCI_BRIDGE_RESOURCES) {
2746		/* device specific resource */
2747		reg = pci_iov_resource_bar(dev, resno, type);
2748		if (reg)
2749			return reg;
2750	}
2751
2752	dev_err(&dev->dev, "BAR %d: invalid resource\n", resno);
2753	return 0;
2754}
2755
2756/* Some architectures require additional programming to enable VGA */
2757static arch_set_vga_state_t arch_set_vga_state;
2758
2759void __init pci_register_set_vga_state(arch_set_vga_state_t func)
2760{
2761	arch_set_vga_state = func;	/* NULL disables */
2762}
2763
2764static int pci_set_vga_state_arch(struct pci_dev *dev, bool decode,
2765		      unsigned int command_bits, bool change_bridge)
2766{
2767	if (arch_set_vga_state)
2768		return arch_set_vga_state(dev, decode, command_bits,
2769						change_bridge);
2770	return 0;
2771}
2772
2773/**
2774 * pci_set_vga_state - set VGA decode state on device and parents if requested
2775 * @dev: the PCI device
2776 * @decode: true = enable decoding, false = disable decoding
2777 * @command_bits: PCI_COMMAND_IO and/or PCI_COMMAND_MEMORY
2778 * @change_bridge: traverse ancestors and change bridges
2779 */
2780int pci_set_vga_state(struct pci_dev *dev, bool decode,
2781		      unsigned int command_bits, bool change_bridge)
2782{
2783	struct pci_bus *bus;
2784	struct pci_dev *bridge;
2785	u16 cmd;
2786	int rc;
2787
2788	WARN_ON(command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY));
2789
2790	/* ARCH specific VGA enables */
2791	rc = pci_set_vga_state_arch(dev, decode, command_bits, change_bridge);
2792	if (rc)
2793		return rc;
2794
2795	pci_read_config_word(dev, PCI_COMMAND, &cmd);
2796	if (decode == true)
2797		cmd |= command_bits;
2798	else
2799		cmd &= ~command_bits;
2800	pci_write_config_word(dev, PCI_COMMAND, cmd);
2801
2802	if (change_bridge == false)
2803		return 0;
2804
2805	bus = dev->bus;
2806	while (bus) {
2807		bridge = bus->self;
2808		if (bridge) {
2809			pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
2810					     &cmd);
2811			if (decode == true)
2812				cmd |= PCI_BRIDGE_CTL_VGA;
2813			else
2814				cmd &= ~PCI_BRIDGE_CTL_VGA;
2815			pci_write_config_word(bridge, PCI_BRIDGE_CONTROL,
2816					      cmd);
2817		}
2818		bus = bus->parent;
2819	}
2820	return 0;
2821}
2822
2823#define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
2824static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
2825static DEFINE_SPINLOCK(resource_alignment_lock);
2826
2827/**
2828 * pci_specified_resource_alignment - get resource alignment specified by user.
2829 * @dev: the PCI device to get
2830 *
2831 * RETURNS: Resource alignment if it is specified.
2832 *          Zero if it is not specified.
2833 */
2834resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
2835{
2836	int seg, bus, slot, func, align_order, count;
2837	resource_size_t align = 0;
2838	char *p;
2839
2840	spin_lock(&resource_alignment_lock);
2841	p = resource_alignment_param;
2842	while (*p) {
2843		count = 0;
2844		if (sscanf(p, "%d%n", &align_order, &count) == 1 &&
2845							p[count] == '@') {
2846			p += count + 1;
2847		} else {
2848			align_order = -1;
2849		}
2850		if (sscanf(p, "%x:%x:%x.%x%n",
2851			&seg, &bus, &slot, &func, &count) != 4) {
2852			seg = 0;
2853			if (sscanf(p, "%x:%x.%x%n",
2854					&bus, &slot, &func, &count) != 3) {
2855				/* Invalid format */
2856				printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
2857					p);
2858				break;
2859			}
2860		}
2861		p += count;
2862		if (seg == pci_domain_nr(dev->bus) &&
2863			bus == dev->bus->number &&
2864			slot == PCI_SLOT(dev->devfn) &&
2865			func == PCI_FUNC(dev->devfn)) {
2866			if (align_order == -1) {
2867				align = PAGE_SIZE;
2868			} else {
2869				align = 1 << align_order;
2870			}
2871			/* Found */
2872			break;
2873		}
2874		if (*p != ';' && *p != ',') {
2875			/* End of param or invalid format */
2876			break;
2877		}
2878		p++;
2879	}
2880	spin_unlock(&resource_alignment_lock);
2881	return align;
2882}
2883
2884/**
2885 * pci_is_reassigndev - check if specified PCI is target device to reassign
2886 * @dev: the PCI device to check
2887 *
2888 * RETURNS: non-zero for PCI device is a target device to reassign,
2889 *          or zero is not.
2890 */
2891int pci_is_reassigndev(struct pci_dev *dev)
2892{
2893	return (pci_specified_resource_alignment(dev) != 0);
2894}
2895
2896ssize_t pci_set_resource_alignment_param(const char *buf, size_t count)
2897{
2898	if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1)
2899		count = RESOURCE_ALIGNMENT_PARAM_SIZE - 1;
2900	spin_lock(&resource_alignment_lock);
2901	strncpy(resource_alignment_param, buf, count);
2902	resource_alignment_param[count] = '\0';
2903	spin_unlock(&resource_alignment_lock);
2904	return count;
2905}
2906
2907ssize_t pci_get_resource_alignment_param(char *buf, size_t size)
2908{
2909	size_t count;
2910	spin_lock(&resource_alignment_lock);
2911	count = snprintf(buf, size, "%s", resource_alignment_param);
2912	spin_unlock(&resource_alignment_lock);
2913	return count;
2914}
2915
2916static ssize_t pci_resource_alignment_show(struct bus_type *bus, char *buf)
2917{
2918	return pci_get_resource_alignment_param(buf, PAGE_SIZE);
2919}
2920
2921static ssize_t pci_resource_alignment_store(struct bus_type *bus,
2922					const char *buf, size_t count)
2923{
2924	return pci_set_resource_alignment_param(buf, count);
2925}
2926
2927BUS_ATTR(resource_alignment, 0644, pci_resource_alignment_show,
2928					pci_resource_alignment_store);
2929
2930static int __init pci_resource_alignment_sysfs_init(void)
2931{
2932	return bus_create_file(&pci_bus_type,
2933					&bus_attr_resource_alignment);
2934}
2935
2936late_initcall(pci_resource_alignment_sysfs_init);
2937
2938static void __devinit pci_no_domains(void)
2939{
2940#ifdef CONFIG_PCI_DOMAINS
2941	pci_domains_supported = 0;
2942#endif
2943}
2944
2945/**
2946 * pci_ext_cfg_enabled - can we access extended PCI config space?
2947 * @dev: The PCI device of the root bridge.
2948 *
2949 * Returns 1 if we can access PCI extended config space (offsets
2950 * greater than 0xff). This is the default implementation. Architecture
2951 * implementations can override this.
2952 */
2953int __attribute__ ((weak)) pci_ext_cfg_avail(struct pci_dev *dev)
2954{
2955	return 1;
2956}
2957
2958void __weak pci_fixup_cardbus(struct pci_bus *bus)
2959{
2960}
2961EXPORT_SYMBOL(pci_fixup_cardbus);
2962
2963static int __init pci_setup(char *str)
2964{
2965	while (str) {
2966		char *k = strchr(str, ',');
2967		if (k)
2968			*k++ = 0;
2969		if (*str && (str = pcibios_setup(str)) && *str) {
2970			if (!strcmp(str, "nomsi")) {
2971				pci_no_msi();
2972			} else if (!strcmp(str, "noaer")) {
2973				pci_no_aer();
2974			} else if (!strcmp(str, "nodomains")) {
2975				pci_no_domains();
2976			} else if (!strncmp(str, "cbiosize=", 9)) {
2977				pci_cardbus_io_size = memparse(str + 9, &str);
2978			} else if (!strncmp(str, "cbmemsize=", 10)) {
2979				pci_cardbus_mem_size = memparse(str + 10, &str);
2980			} else if (!strncmp(str, "resource_alignment=", 19)) {
2981				pci_set_resource_alignment_param(str + 19,
2982							strlen(str + 19));
2983			} else if (!strncmp(str, "ecrc=", 5)) {
2984				pcie_ecrc_get_policy(str + 5);
2985			} else if (!strncmp(str, "hpiosize=", 9)) {
2986				pci_hotplug_io_size = memparse(str + 9, &str);
2987			} else if (!strncmp(str, "hpmemsize=", 10)) {
2988				pci_hotplug_mem_size = memparse(str + 10, &str);
2989			} else {
2990				printk(KERN_ERR "PCI: Unknown option `%s'\n",
2991						str);
2992			}
2993		}
2994		str = k;
2995	}
2996	return 0;
2997}
2998early_param("pci", pci_setup);
2999
3000EXPORT_SYMBOL(pci_reenable_device);
3001EXPORT_SYMBOL(pci_enable_device_io);
3002EXPORT_SYMBOL(pci_enable_device_mem);
3003EXPORT_SYMBOL(pci_enable_device);
3004EXPORT_SYMBOL(pcim_enable_device);
3005EXPORT_SYMBOL(pcim_pin_device);
3006EXPORT_SYMBOL(pci_disable_device);
3007EXPORT_SYMBOL(pci_find_capability);
3008EXPORT_SYMBOL(pci_bus_find_capability);
3009EXPORT_SYMBOL(pci_release_regions);
3010EXPORT_SYMBOL(pci_request_regions);
3011EXPORT_SYMBOL(pci_request_regions_exclusive);
3012EXPORT_SYMBOL(pci_release_region);
3013EXPORT_SYMBOL(pci_request_region);
3014EXPORT_SYMBOL(pci_request_region_exclusive);
3015EXPORT_SYMBOL(pci_release_selected_regions);
3016EXPORT_SYMBOL(pci_request_selected_regions);
3017EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
3018EXPORT_SYMBOL(pci_set_master);
3019EXPORT_SYMBOL(pci_clear_master);
3020EXPORT_SYMBOL(pci_set_mwi);
3021EXPORT_SYMBOL(pci_try_set_mwi);
3022EXPORT_SYMBOL(pci_clear_mwi);
3023EXPORT_SYMBOL_GPL(pci_intx);
3024EXPORT_SYMBOL(pci_assign_resource);
3025EXPORT_SYMBOL(pci_find_parent_resource);
3026EXPORT_SYMBOL(pci_select_bars);
3027
3028EXPORT_SYMBOL(pci_set_power_state);
3029EXPORT_SYMBOL(pci_save_state);
3030EXPORT_SYMBOL(pci_restore_state);
3031EXPORT_SYMBOL(pci_pme_capable);
3032EXPORT_SYMBOL(pci_pme_active);
3033EXPORT_SYMBOL(pci_wake_from_d3);
3034EXPORT_SYMBOL(pci_target_state);
3035EXPORT_SYMBOL(pci_prepare_to_sleep);
3036EXPORT_SYMBOL(pci_back_from_sleep);
3037EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);
3038