Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
f7625980 | 2 | * PCI searching functions. |
1da177e4 LT |
3 | * |
4 | * Copyright (C) 1993 -- 1997 Drew Eckhardt, Frederic Potter, | |
5 | * David Mosberger-Tang | |
6 | * Copyright (C) 1997 -- 2000 Martin Mares <mj@ucw.cz> | |
7 | * Copyright (C) 2003 -- 2004 Greg Kroah-Hartman <greg@kroah.com> | |
8 | */ | |
9 | ||
10 | #include <linux/init.h> | |
11 | #include <linux/pci.h> | |
5a0e3ad6 | 12 | #include <linux/slab.h> |
1da177e4 LT |
13 | #include <linux/module.h> |
14 | #include <linux/interrupt.h> | |
15 | #include "pci.h" | |
16 | ||
d71374da | 17 | DECLARE_RWSEM(pci_bus_sem); |
ce29ca3e AK |
18 | EXPORT_SYMBOL_GPL(pci_bus_sem); |
19 | ||
c25dc828 AW |
20 | /* |
21 | * pci_for_each_dma_alias - Iterate over DMA aliases for a device | |
22 | * @pdev: starting downstream device | |
23 | * @fn: function to call for each alias | |
24 | * @data: opaque data to pass to @fn | |
25 | * | |
26 | * Starting @pdev, walk up the bus calling @fn for each possible alias | |
27 | * of @pdev at the root bus. | |
28 | */ | |
29 | int pci_for_each_dma_alias(struct pci_dev *pdev, | |
30 | int (*fn)(struct pci_dev *pdev, | |
31 | u16 alias, void *data), void *data) | |
32 | { | |
33 | struct pci_bus *bus; | |
34 | int ret; | |
35 | ||
36 | ret = fn(pdev, PCI_DEVID(pdev->bus->number, pdev->devfn), data); | |
37 | if (ret) | |
38 | return ret; | |
39 | ||
31c2b815 AW |
40 | /* |
41 | * If the device is broken and uses an alias requester ID for | |
42 | * DMA, iterate over that too. | |
43 | */ | |
44 | if (unlikely(pdev->dev_flags & PCI_DEV_FLAGS_DMA_ALIAS_DEVFN)) { | |
45 | ret = fn(pdev, PCI_DEVID(pdev->bus->number, | |
46 | pdev->dma_alias_devfn), data); | |
47 | if (ret) | |
48 | return ret; | |
49 | } | |
50 | ||
c25dc828 AW |
51 | for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) { |
52 | struct pci_dev *tmp; | |
53 | ||
54 | /* Skip virtual buses */ | |
55 | if (!bus->self) | |
56 | continue; | |
57 | ||
58 | tmp = bus->self; | |
59 | ||
60 | /* | |
61 | * PCIe-to-PCI/X bridges alias transactions from downstream | |
62 | * devices using the subordinate bus number (PCI Express to | |
63 | * PCI/PCI-X Bridge Spec, rev 1.0, sec 2.3). For all cases | |
64 | * where the upstream bus is PCI/X we alias to the bridge | |
65 | * (there are various conditions in the previous reference | |
66 | * where the bridge may take ownership of transactions, even | |
67 | * when the secondary interface is PCI-X). | |
68 | */ | |
69 | if (pci_is_pcie(tmp)) { | |
70 | switch (pci_pcie_type(tmp)) { | |
71 | case PCI_EXP_TYPE_ROOT_PORT: | |
72 | case PCI_EXP_TYPE_UPSTREAM: | |
73 | case PCI_EXP_TYPE_DOWNSTREAM: | |
74 | continue; | |
75 | case PCI_EXP_TYPE_PCI_BRIDGE: | |
76 | ret = fn(tmp, | |
77 | PCI_DEVID(tmp->subordinate->number, | |
78 | PCI_DEVFN(0, 0)), data); | |
79 | if (ret) | |
80 | return ret; | |
81 | continue; | |
82 | case PCI_EXP_TYPE_PCIE_BRIDGE: | |
83 | ret = fn(tmp, | |
84 | PCI_DEVID(tmp->bus->number, | |
85 | tmp->devfn), data); | |
86 | if (ret) | |
87 | return ret; | |
88 | continue; | |
89 | } | |
90 | } else { | |
91 | ret = fn(tmp, PCI_DEVID(tmp->bus->number, tmp->devfn), | |
92 | data); | |
93 | if (ret) | |
94 | return ret; | |
95 | } | |
96 | } | |
97 | ||
98 | return ret; | |
99 | } | |
100 | ||
994a65e2 | 101 | /* |
45e829ea | 102 | * find the upstream PCIe-to-PCI bridge of a PCI device |
994a65e2 | 103 | * if the device is PCIE, return NULL |
45e829ea | 104 | * if the device isn't connected to a PCIe bridge (that is its parent is a |
994a65e2 KA |
105 | * legacy PCI bridge and the bridge is directly connected to bus 0), return its |
106 | * parent | |
107 | */ | |
108 | struct pci_dev * | |
109 | pci_find_upstream_pcie_bridge(struct pci_dev *pdev) | |
110 | { | |
111 | struct pci_dev *tmp = NULL; | |
112 | ||
5f4d91a1 | 113 | if (pci_is_pcie(pdev)) |
994a65e2 KA |
114 | return NULL; |
115 | while (1) { | |
6e3f36df | 116 | if (pci_is_root_bus(pdev->bus)) |
994a65e2 KA |
117 | break; |
118 | pdev = pdev->bus->self; | |
119 | /* a p2p bridge */ | |
5f4d91a1 | 120 | if (!pci_is_pcie(pdev)) { |
994a65e2 KA |
121 | tmp = pdev; |
122 | continue; | |
123 | } | |
45e829ea | 124 | /* PCI device should connect to a PCIe bridge */ |
62f87c0e | 125 | if (pci_pcie_type(pdev) != PCI_EXP_TYPE_PCI_BRIDGE) { |
994a65e2 KA |
126 | /* Busted hardware? */ |
127 | WARN_ON_ONCE(1); | |
128 | return NULL; | |
129 | } | |
130 | return pdev; | |
131 | } | |
132 | ||
133 | return tmp; | |
134 | } | |
1da177e4 | 135 | |
96bde06a | 136 | static struct pci_bus *pci_do_find_bus(struct pci_bus *bus, unsigned char busnr) |
1da177e4 | 137 | { |
94e6a9b9 YW |
138 | struct pci_bus *child; |
139 | struct pci_bus *tmp; | |
1da177e4 LT |
140 | |
141 | if(bus->number == busnr) | |
142 | return bus; | |
143 | ||
94e6a9b9 YW |
144 | list_for_each_entry(tmp, &bus->children, node) { |
145 | child = pci_do_find_bus(tmp, busnr); | |
1da177e4 LT |
146 | if(child) |
147 | return child; | |
148 | } | |
149 | return NULL; | |
150 | } | |
151 | ||
152 | /** | |
153 | * pci_find_bus - locate PCI bus from a given domain and bus number | |
154 | * @domain: number of PCI domain to search | |
155 | * @busnr: number of desired PCI bus | |
156 | * | |
157 | * Given a PCI bus number and domain number, the desired PCI bus is located | |
158 | * in the global list of PCI buses. If the bus is found, a pointer to its | |
159 | * data structure is returned. If no bus is found, %NULL is returned. | |
160 | */ | |
c8439cfc | 161 | struct pci_bus * pci_find_bus(int domain, int busnr) |
1da177e4 LT |
162 | { |
163 | struct pci_bus *bus = NULL; | |
164 | struct pci_bus *tmp_bus; | |
165 | ||
166 | while ((bus = pci_find_next_bus(bus)) != NULL) { | |
167 | if (pci_domain_nr(bus) != domain) | |
168 | continue; | |
169 | tmp_bus = pci_do_find_bus(bus, busnr); | |
170 | if (tmp_bus) | |
171 | return tmp_bus; | |
172 | } | |
173 | return NULL; | |
174 | } | |
175 | ||
176 | /** | |
177 | * pci_find_next_bus - begin or continue searching for a PCI bus | |
178 | * @from: Previous PCI bus found, or %NULL for new search. | |
179 | * | |
f7625980 | 180 | * Iterates through the list of known PCI buses. A new search is |
d75763d2 | 181 | * initiated by passing %NULL as the @from argument. Otherwise if |
1da177e4 LT |
182 | * @from is not %NULL, searches continue from next device on the |
183 | * global list. | |
184 | */ | |
f7625980 | 185 | struct pci_bus * |
1da177e4 LT |
186 | pci_find_next_bus(const struct pci_bus *from) |
187 | { | |
188 | struct list_head *n; | |
189 | struct pci_bus *b = NULL; | |
190 | ||
191 | WARN_ON(in_interrupt()); | |
d71374da | 192 | down_read(&pci_bus_sem); |
1da177e4 LT |
193 | n = from ? from->node.next : pci_root_buses.next; |
194 | if (n != &pci_root_buses) | |
94e6a9b9 | 195 | b = list_entry(n, struct pci_bus, node); |
d71374da | 196 | up_read(&pci_bus_sem); |
1da177e4 LT |
197 | return b; |
198 | } | |
199 | ||
1da177e4 LT |
200 | /** |
201 | * pci_get_slot - locate PCI device for a given PCI slot | |
202 | * @bus: PCI bus on which desired PCI device resides | |
f7625980 BH |
203 | * @devfn: encodes number of PCI slot in which the desired PCI |
204 | * device resides and the logical device number within that slot | |
1da177e4 LT |
205 | * in case of multi-function devices. |
206 | * | |
f7625980 | 207 | * Given a PCI bus and slot/function number, the desired PCI device |
1da177e4 LT |
208 | * is located in the list of PCI devices. |
209 | * If the device is found, its reference count is increased and this | |
210 | * function returns a pointer to its data structure. The caller must | |
211 | * decrement the reference count by calling pci_dev_put(). | |
212 | * If no device is found, %NULL is returned. | |
213 | */ | |
66455f54 | 214 | struct pci_dev *pci_get_slot(struct pci_bus *bus, unsigned int devfn) |
1da177e4 | 215 | { |
1da177e4 LT |
216 | struct pci_dev *dev; |
217 | ||
218 | WARN_ON(in_interrupt()); | |
d71374da | 219 | down_read(&pci_bus_sem); |
1da177e4 | 220 | |
66455f54 | 221 | list_for_each_entry(dev, &bus->devices, bus_list) { |
1da177e4 LT |
222 | if (dev->devfn == devfn) |
223 | goto out; | |
224 | } | |
225 | ||
226 | dev = NULL; | |
227 | out: | |
228 | pci_dev_get(dev); | |
d71374da | 229 | up_read(&pci_bus_sem); |
1da177e4 LT |
230 | return dev; |
231 | } | |
232 | ||
29f3eb64 | 233 | /** |
3c299dc2 AP |
234 | * pci_get_domain_bus_and_slot - locate PCI device for a given PCI domain (segment), bus, and slot |
235 | * @domain: PCI domain/segment on which the PCI device resides. | |
236 | * @bus: PCI bus on which desired PCI device resides | |
237 | * @devfn: encodes number of PCI slot in which the desired PCI device | |
238 | * resides and the logical device number within that slot in case of | |
239 | * multi-function devices. | |
5463d9f0 | 240 | * |
3c299dc2 AP |
241 | * Given a PCI domain, bus, and slot/function number, the desired PCI |
242 | * device is located in the list of PCI devices. If the device is | |
243 | * found, its reference count is increased and this function returns a | |
244 | * pointer to its data structure. The caller must decrement the | |
245 | * reference count by calling pci_dev_put(). If no device is found, | |
246 | * %NULL is returned. | |
29f3eb64 | 247 | */ |
3c299dc2 AP |
248 | struct pci_dev *pci_get_domain_bus_and_slot(int domain, unsigned int bus, |
249 | unsigned int devfn) | |
29f3eb64 AC |
250 | { |
251 | struct pci_dev *dev = NULL; | |
252 | ||
4e344b1c | 253 | for_each_pci_dev(dev) { |
3c299dc2 AP |
254 | if (pci_domain_nr(dev->bus) == domain && |
255 | (dev->bus->number == bus && dev->devfn == devfn)) | |
29f3eb64 AC |
256 | return dev; |
257 | } | |
258 | return NULL; | |
259 | } | |
3c299dc2 | 260 | EXPORT_SYMBOL(pci_get_domain_bus_and_slot); |
29f3eb64 | 261 | |
95247b57 | 262 | static int match_pci_dev_by_id(struct device *dev, void *data) |
1da177e4 | 263 | { |
95247b57 GKH |
264 | struct pci_dev *pdev = to_pci_dev(dev); |
265 | struct pci_device_id *id = data; | |
1da177e4 | 266 | |
95247b57 GKH |
267 | if (pci_match_one_device(id, pdev)) |
268 | return 1; | |
269 | return 0; | |
1da177e4 LT |
270 | } |
271 | ||
95247b57 GKH |
272 | /* |
273 | * pci_get_dev_by_id - begin or continue searching for a PCI device by id | |
274 | * @id: pointer to struct pci_device_id to match for the device | |
1da177e4 LT |
275 | * @from: Previous PCI device found in search, or %NULL for new search. |
276 | * | |
d75763d2 | 277 | * Iterates through the list of known PCI devices. If a PCI device is found |
95247b57 GKH |
278 | * with a matching id a pointer to its device structure is returned, and the |
279 | * reference count to the device is incremented. Otherwise, %NULL is returned. | |
280 | * A new search is initiated by passing %NULL as the @from argument. Otherwise | |
281 | * if @from is not %NULL, searches continue from next device on the global | |
282 | * list. The reference count for @from is always decremented if it is not | |
283 | * %NULL. | |
284 | * | |
285 | * This is an internal function for use by the other search functions in | |
286 | * this file. | |
1da177e4 | 287 | */ |
95247b57 | 288 | static struct pci_dev *pci_get_dev_by_id(const struct pci_device_id *id, |
b08508c4 | 289 | struct pci_dev *from) |
1da177e4 | 290 | { |
95247b57 GKH |
291 | struct device *dev; |
292 | struct device *dev_start = NULL; | |
293 | struct pci_dev *pdev = NULL; | |
294 | ||
295 | WARN_ON(in_interrupt()); | |
c4ed02fa MW |
296 | if (from) |
297 | dev_start = &from->dev; | |
95247b57 GKH |
298 | dev = bus_find_device(&pci_bus_type, dev_start, (void *)id, |
299 | match_pci_dev_by_id); | |
300 | if (dev) | |
301 | pdev = to_pci_dev(dev); | |
ebca4f1b GK |
302 | if (from) |
303 | pci_dev_put(from); | |
95247b57 | 304 | return pdev; |
1da177e4 LT |
305 | } |
306 | ||
307 | /** | |
308 | * pci_get_subsys - begin or continue searching for a PCI device by vendor/subvendor/device/subdevice id | |
309 | * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids | |
310 | * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids | |
311 | * @ss_vendor: PCI subsystem vendor id to match, or %PCI_ANY_ID to match all vendor ids | |
312 | * @ss_device: PCI subsystem device id to match, or %PCI_ANY_ID to match all device ids | |
313 | * @from: Previous PCI device found in search, or %NULL for new search. | |
314 | * | |
d75763d2 RD |
315 | * Iterates through the list of known PCI devices. If a PCI device is found |
316 | * with a matching @vendor, @device, @ss_vendor and @ss_device, a pointer to its | |
1da177e4 LT |
317 | * device structure is returned, and the reference count to the device is |
318 | * incremented. Otherwise, %NULL is returned. A new search is initiated by | |
d75763d2 | 319 | * passing %NULL as the @from argument. Otherwise if @from is not %NULL, |
1da177e4 LT |
320 | * searches continue from next device on the global list. |
321 | * The reference count for @from is always decremented if it is not %NULL. | |
322 | */ | |
95247b57 GKH |
323 | struct pci_dev *pci_get_subsys(unsigned int vendor, unsigned int device, |
324 | unsigned int ss_vendor, unsigned int ss_device, | |
b08508c4 | 325 | struct pci_dev *from) |
1da177e4 | 326 | { |
b9443f40 FT |
327 | struct pci_device_id id = { |
328 | .vendor = vendor, | |
329 | .device = device, | |
330 | .subvendor = ss_vendor, | |
331 | .subdevice = ss_device, | |
332 | }; | |
6ae4adf5 | 333 | |
b9443f40 | 334 | return pci_get_dev_by_id(&id, from); |
1da177e4 LT |
335 | } |
336 | ||
337 | /** | |
338 | * pci_get_device - begin or continue searching for a PCI device by vendor/device id | |
339 | * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids | |
340 | * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids | |
341 | * @from: Previous PCI device found in search, or %NULL for new search. | |
342 | * | |
343 | * Iterates through the list of known PCI devices. If a PCI device is | |
344 | * found with a matching @vendor and @device, the reference count to the | |
345 | * device is incremented and a pointer to its device structure is returned. | |
346 | * Otherwise, %NULL is returned. A new search is initiated by passing %NULL | |
d75763d2 | 347 | * as the @from argument. Otherwise if @from is not %NULL, searches continue |
1da177e4 LT |
348 | * from next device on the global list. The reference count for @from is |
349 | * always decremented if it is not %NULL. | |
350 | */ | |
351 | struct pci_dev * | |
352 | pci_get_device(unsigned int vendor, unsigned int device, struct pci_dev *from) | |
353 | { | |
354 | return pci_get_subsys(vendor, device, PCI_ANY_ID, PCI_ANY_ID, from); | |
355 | } | |
356 | ||
1da177e4 LT |
357 | /** |
358 | * pci_get_class - begin or continue searching for a PCI device by class | |
359 | * @class: search for a PCI device with this class designation | |
360 | * @from: Previous PCI device found in search, or %NULL for new search. | |
361 | * | |
362 | * Iterates through the list of known PCI devices. If a PCI device is | |
363 | * found with a matching @class, the reference count to the device is | |
364 | * incremented and a pointer to its device structure is returned. | |
365 | * Otherwise, %NULL is returned. | |
d75763d2 | 366 | * A new search is initiated by passing %NULL as the @from argument. |
1da177e4 LT |
367 | * Otherwise if @from is not %NULL, searches continue from next device |
368 | * on the global list. The reference count for @from is always decremented | |
369 | * if it is not %NULL. | |
370 | */ | |
371 | struct pci_dev *pci_get_class(unsigned int class, struct pci_dev *from) | |
372 | { | |
b9443f40 FT |
373 | struct pci_device_id id = { |
374 | .vendor = PCI_ANY_ID, | |
375 | .device = PCI_ANY_ID, | |
376 | .subvendor = PCI_ANY_ID, | |
377 | .subdevice = PCI_ANY_ID, | |
378 | .class_mask = PCI_ANY_ID, | |
379 | .class = class, | |
380 | }; | |
381 | ||
382 | return pci_get_dev_by_id(&id, from); | |
1da177e4 LT |
383 | } |
384 | ||
448432c4 GKH |
385 | /** |
386 | * pci_dev_present - Returns 1 if device matching the device list is present, 0 if not. | |
387 | * @ids: A pointer to a null terminated list of struct pci_device_id structures | |
388 | * that describe the type of PCI device the caller is trying to find. | |
389 | * | |
390 | * Obvious fact: You do not have a reference to any device that might be found | |
391 | * by this function, so if that device is removed from the system right after | |
392 | * this function is finished, the value will be stale. Use this function to | |
393 | * find devices that are usually built into a system, or for a general hint as | |
394 | * to if another device happens to be present at this specific moment in time. | |
395 | */ | |
396 | int pci_dev_present(const struct pci_device_id *ids) | |
d86f90f9 | 397 | { |
95247b57 | 398 | struct pci_dev *found = NULL; |
d86f90f9 AC |
399 | |
400 | WARN_ON(in_interrupt()); | |
d86f90f9 | 401 | while (ids->vendor || ids->subvendor || ids->class_mask) { |
95247b57 | 402 | found = pci_get_dev_by_id(ids, NULL); |
d5af7d98 JL |
403 | if (found) { |
404 | pci_dev_put(found); | |
405 | return 1; | |
406 | } | |
d86f90f9 AC |
407 | ids++; |
408 | } | |
d5af7d98 | 409 | |
448432c4 | 410 | return 0; |
1da177e4 LT |
411 | } |
412 | EXPORT_SYMBOL(pci_dev_present); | |
413 | ||
29f3eb64 AC |
414 | /* For boot time work */ |
415 | EXPORT_SYMBOL(pci_find_bus); | |
416 | EXPORT_SYMBOL(pci_find_next_bus); | |
417 | /* For everyone */ | |
1da177e4 LT |
418 | EXPORT_SYMBOL(pci_get_device); |
419 | EXPORT_SYMBOL(pci_get_subsys); | |
420 | EXPORT_SYMBOL(pci_get_slot); | |
421 | EXPORT_SYMBOL(pci_get_class); |