Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * drivers/pci/bus.c | |
3 | * | |
4 | * From setup-res.c, by: | |
5 | * Dave Rusling (david.rusling@reo.mts.dec.com) | |
6 | * David Mosberger (davidm@cs.arizona.edu) | |
7 | * David Miller (davem@redhat.com) | |
8 | * Ivan Kokshaysky (ink@jurassic.park.msu.ru) | |
9 | */ | |
10 | #include <linux/module.h> | |
11 | #include <linux/kernel.h> | |
12 | #include <linux/pci.h> | |
13 | #include <linux/errno.h> | |
14 | #include <linux/ioport.h> | |
15 | #include <linux/proc_fs.h> | |
16 | #include <linux/init.h> | |
5a0e3ad6 | 17 | #include <linux/slab.h> |
1da177e4 LT |
18 | |
19 | #include "pci.h" | |
20 | ||
2fe2abf8 BH |
21 | void pci_bus_add_resource(struct pci_bus *bus, struct resource *res, |
22 | unsigned int flags) | |
23 | { | |
24 | struct pci_bus_resource *bus_res; | |
25 | ||
26 | bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL); | |
27 | if (!bus_res) { | |
28 | dev_err(&bus->dev, "can't add %pR resource\n", res); | |
29 | return; | |
30 | } | |
31 | ||
32 | bus_res->res = res; | |
33 | bus_res->flags = flags; | |
34 | list_add_tail(&bus_res->list, &bus->resources); | |
35 | } | |
36 | ||
37 | struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n) | |
38 | { | |
39 | struct pci_bus_resource *bus_res; | |
40 | ||
41 | if (n < PCI_BRIDGE_RESOURCE_NUM) | |
42 | return bus->resource[n]; | |
43 | ||
44 | n -= PCI_BRIDGE_RESOURCE_NUM; | |
45 | list_for_each_entry(bus_res, &bus->resources, list) { | |
46 | if (n-- == 0) | |
47 | return bus_res->res; | |
48 | } | |
49 | return NULL; | |
50 | } | |
51 | EXPORT_SYMBOL_GPL(pci_bus_resource_n); | |
52 | ||
53 | void pci_bus_remove_resources(struct pci_bus *bus) | |
54 | { | |
55 | struct pci_bus_resource *bus_res, *tmp; | |
56 | int i; | |
57 | ||
58 | for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) | |
7736a05a | 59 | bus->resource[i] = NULL; |
2fe2abf8 BH |
60 | |
61 | list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) { | |
62 | list_del(&bus_res->list); | |
63 | kfree(bus_res); | |
64 | } | |
65 | } | |
66 | ||
82e3e767 BH |
67 | static bool pci_bus_resource_better(struct resource *res1, bool pos1, |
68 | struct resource *res2, bool pos2) | |
69 | { | |
70 | /* If exactly one is positive decode, always prefer that one */ | |
71 | if (pos1 != pos2) | |
72 | return pos1 ? true : false; | |
73 | ||
74 | /* Prefer the one that contains the highest address */ | |
75 | if (res1->end != res2->end) | |
76 | return (res1->end > res2->end) ? true : false; | |
77 | ||
78 | /* Otherwise, prefer the one with highest "center of gravity" */ | |
79 | if (res1->start != res2->start) | |
80 | return (res1->start > res2->start) ? true : false; | |
81 | ||
82 | /* Otherwise, choose one arbitrarily (but consistently) */ | |
83 | return (res1 > res2) ? true : false; | |
84 | } | |
85 | ||
86 | static bool pci_bus_resource_positive(struct pci_bus *bus, struct resource *res) | |
87 | { | |
88 | struct pci_bus_resource *bus_res; | |
89 | ||
90 | /* | |
91 | * This relies on the fact that pci_bus.resource[] refers to P2P or | |
92 | * CardBus bridge base/limit registers, which are always positively | |
93 | * decoded. The pci_bus.resources list contains host bridge or | |
94 | * subtractively decoded resources. | |
95 | */ | |
96 | list_for_each_entry(bus_res, &bus->resources, list) { | |
97 | if (bus_res->res == res) | |
98 | return (bus_res->flags & PCI_SUBTRACTIVE_DECODE) ? | |
99 | false : true; | |
100 | } | |
101 | return true; | |
102 | } | |
103 | ||
b126b470 | 104 | /* |
82e3e767 BH |
105 | * Find the next-best bus resource after the cursor "res". If the cursor is |
106 | * NULL, return the best resource. "Best" means that we prefer positive | |
107 | * decode regions over subtractive decode, then those at higher addresses. | |
b126b470 BH |
108 | */ |
109 | static struct resource *pci_bus_find_resource_prev(struct pci_bus *bus, | |
110 | unsigned int type, | |
111 | struct resource *res) | |
112 | { | |
82e3e767 | 113 | bool res_pos, r_pos, prev_pos = false; |
b126b470 BH |
114 | struct resource *r, *prev = NULL; |
115 | int i; | |
116 | ||
82e3e767 | 117 | res_pos = pci_bus_resource_positive(bus, res); |
b126b470 BH |
118 | pci_bus_for_each_resource(bus, r, i) { |
119 | if (!r) | |
120 | continue; | |
121 | ||
122 | if ((r->flags & IORESOURCE_TYPE_BITS) != type) | |
123 | continue; | |
124 | ||
82e3e767 BH |
125 | r_pos = pci_bus_resource_positive(bus, r); |
126 | if (!res || pci_bus_resource_better(res, res_pos, r, r_pos)) { | |
127 | if (!prev || pci_bus_resource_better(r, r_pos, | |
128 | prev, prev_pos)) { | |
129 | prev = r; | |
130 | prev_pos = r_pos; | |
131 | } | |
b126b470 | 132 | } |
b126b470 BH |
133 | } |
134 | ||
135 | return prev; | |
136 | } | |
137 | ||
1da177e4 LT |
138 | /** |
139 | * pci_bus_alloc_resource - allocate a resource from a parent bus | |
140 | * @bus: PCI bus | |
141 | * @res: resource to allocate | |
142 | * @size: size of resource to allocate | |
143 | * @align: alignment of resource to allocate | |
144 | * @min: minimum /proc/iomem address to allocate | |
145 | * @type_mask: IORESOURCE_* type flags | |
146 | * @alignf: resource alignment function | |
147 | * @alignf_data: data argument for resource alignment function | |
148 | * | |
149 | * Given the PCI bus a device resides on, the size, minimum address, | |
150 | * alignment and type, try to find an acceptable resource allocation | |
151 | * for a specific device resource. | |
152 | */ | |
153 | int | |
154 | pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res, | |
e31dd6e4 GKH |
155 | resource_size_t size, resource_size_t align, |
156 | resource_size_t min, unsigned int type_mask, | |
b26b2d49 | 157 | resource_size_t (*alignf)(void *, |
3b7a17fc | 158 | const struct resource *, |
b26b2d49 DB |
159 | resource_size_t, |
160 | resource_size_t), | |
e31dd6e4 | 161 | void *alignf_data) |
1da177e4 | 162 | { |
b126b470 | 163 | int ret = -ENOMEM; |
89a74ecc | 164 | struct resource *r; |
1f82de10 | 165 | resource_size_t max = -1; |
b126b470 | 166 | unsigned int type = res->flags & IORESOURCE_TYPE_BITS; |
1da177e4 LT |
167 | |
168 | type_mask |= IORESOURCE_IO | IORESOURCE_MEM; | |
169 | ||
1f82de10 YL |
170 | /* don't allocate too high if the pref mem doesn't support 64bit*/ |
171 | if (!(res->flags & IORESOURCE_MEM_64)) | |
172 | max = PCIBIOS_MAX_MEM_32; | |
173 | ||
b126b470 BH |
174 | /* Look for space at highest addresses first */ |
175 | r = pci_bus_find_resource_prev(bus, type, NULL); | |
176 | for ( ; r; r = pci_bus_find_resource_prev(bus, type, r)) { | |
1da177e4 LT |
177 | /* type_mask must match */ |
178 | if ((res->flags ^ r->flags) & type_mask) | |
179 | continue; | |
180 | ||
181 | /* We cannot allocate a non-prefetching resource | |
182 | from a pre-fetching area */ | |
183 | if ((r->flags & IORESOURCE_PREFETCH) && | |
184 | !(res->flags & IORESOURCE_PREFETCH)) | |
185 | continue; | |
186 | ||
187 | /* Ok, try it out.. */ | |
688d1918 LT |
188 | ret = allocate_resource(r, res, size, |
189 | r->start ? : min, | |
1f82de10 | 190 | max, align, |
1da177e4 LT |
191 | alignf, alignf_data); |
192 | if (ret == 0) | |
193 | break; | |
194 | } | |
195 | return ret; | |
196 | } | |
197 | ||
198 | /** | |
3fa16fdb | 199 | * pci_bus_add_device - add a single device |
1da177e4 LT |
200 | * @dev: device to add |
201 | * | |
202 | * This adds a single pci device to the global | |
203 | * device list and adds sysfs and procfs entries | |
204 | */ | |
96bde06a | 205 | int pci_bus_add_device(struct pci_dev *dev) |
1da177e4 | 206 | { |
b19441af GKH |
207 | int retval; |
208 | retval = device_add(&dev->dev); | |
209 | if (retval) | |
210 | return retval; | |
1da177e4 | 211 | |
8a1bc901 | 212 | dev->is_added = 1; |
1da177e4 LT |
213 | pci_proc_attach_device(dev); |
214 | pci_create_sysfs_dev_files(dev); | |
b19441af | 215 | return 0; |
1da177e4 LT |
216 | } |
217 | ||
876e501a YZ |
218 | /** |
219 | * pci_bus_add_child - add a child bus | |
220 | * @bus: bus to add | |
221 | * | |
222 | * This adds sysfs entries for a single bus | |
223 | */ | |
224 | int pci_bus_add_child(struct pci_bus *bus) | |
225 | { | |
226 | int retval; | |
227 | ||
228 | if (bus->bridge) | |
229 | bus->dev.parent = bus->bridge; | |
230 | ||
231 | retval = device_register(&bus->dev); | |
232 | if (retval) | |
233 | return retval; | |
234 | ||
235 | bus->is_added = 1; | |
236 | ||
237 | retval = device_create_file(&bus->dev, &dev_attr_cpuaffinity); | |
238 | if (retval) | |
239 | return retval; | |
240 | ||
241 | retval = device_create_file(&bus->dev, &dev_attr_cpulistaffinity); | |
242 | ||
243 | /* Create legacy_io and legacy_mem files for this bus */ | |
244 | pci_create_legacy_files(bus); | |
245 | ||
246 | return retval; | |
247 | } | |
248 | ||
1da177e4 LT |
249 | /** |
250 | * pci_bus_add_devices - insert newly discovered PCI devices | |
251 | * @bus: bus to check for new devices | |
252 | * | |
253 | * Add newly discovered PCI devices (which are on the bus->devices | |
254 | * list) to the global PCI device list, add the sysfs and procfs | |
255 | * entries. Where a bridge is found, add the discovered bus to | |
256 | * the parents list of child buses, and recurse (breadth-first | |
257 | * to be compatible with 2.4) | |
258 | * | |
259 | * Call hotplug for each new devices. | |
260 | */ | |
c48f1670 | 261 | void pci_bus_add_devices(const struct pci_bus *bus) |
1da177e4 LT |
262 | { |
263 | struct pci_dev *dev; | |
3fa16fdb | 264 | struct pci_bus *child; |
b19441af | 265 | int retval; |
1da177e4 LT |
266 | |
267 | list_for_each_entry(dev, &bus->devices, bus_list) { | |
8a1bc901 GKH |
268 | /* Skip already-added devices */ |
269 | if (dev->is_added) | |
1da177e4 | 270 | continue; |
b19441af GKH |
271 | retval = pci_bus_add_device(dev); |
272 | if (retval) | |
273 | dev_err(&dev->dev, "Error adding device, continuing\n"); | |
1da177e4 LT |
274 | } |
275 | ||
276 | list_for_each_entry(dev, &bus->devices, bus_list) { | |
8a1bc901 | 277 | BUG_ON(!dev->is_added); |
1da177e4 | 278 | |
3fa16fdb | 279 | child = dev->subordinate; |
1da177e4 LT |
280 | /* |
281 | * If there is an unattached subordinate bus, attach | |
282 | * it and then scan for unattached PCI devices. | |
283 | */ | |
3fa16fdb YZ |
284 | if (!child) |
285 | continue; | |
286 | if (list_empty(&child->node)) { | |
287 | down_write(&pci_bus_sem); | |
288 | list_add_tail(&child->node, &dev->bus->children); | |
289 | up_write(&pci_bus_sem); | |
290 | } | |
291 | pci_bus_add_devices(child); | |
292 | ||
293 | /* | |
294 | * register the bus with sysfs as the parent is now | |
295 | * properly registered. | |
296 | */ | |
297 | if (child->is_added) | |
298 | continue; | |
876e501a | 299 | retval = pci_bus_add_child(child); |
3fa16fdb | 300 | if (retval) |
876e501a | 301 | dev_err(&dev->dev, "Error adding bus, continuing\n"); |
1da177e4 LT |
302 | } |
303 | } | |
304 | ||
305 | void pci_enable_bridges(struct pci_bus *bus) | |
306 | { | |
307 | struct pci_dev *dev; | |
95a62965 | 308 | int retval; |
1da177e4 LT |
309 | |
310 | list_for_each_entry(dev, &bus->devices, bus_list) { | |
311 | if (dev->subordinate) { | |
296ccb08 | 312 | if (!pci_is_enabled(dev)) { |
9dd90caf | 313 | retval = pci_enable_device(dev); |
2eb5ebd3 JW |
314 | if (retval) |
315 | dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n", retval); | |
9dd90caf AC |
316 | pci_set_master(dev); |
317 | } | |
1da177e4 LT |
318 | pci_enable_bridges(dev->subordinate); |
319 | } | |
320 | } | |
321 | } | |
322 | ||
cecf4864 PM |
323 | /** pci_walk_bus - walk devices on/under bus, calling callback. |
324 | * @top bus whose devices should be walked | |
325 | * @cb callback to be called for each device found | |
326 | * @userdata arbitrary pointer to be passed to callback. | |
327 | * | |
328 | * Walk the given bus, including any bridged devices | |
329 | * on buses under this bus. Call the provided callback | |
330 | * on each device found. | |
70298c6e ZY |
331 | * |
332 | * We check the return of @cb each time. If it returns anything | |
333 | * other than 0, we break out. | |
334 | * | |
cecf4864 | 335 | */ |
70298c6e | 336 | void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), |
cecf4864 PM |
337 | void *userdata) |
338 | { | |
339 | struct pci_dev *dev; | |
340 | struct pci_bus *bus; | |
341 | struct list_head *next; | |
70298c6e | 342 | int retval; |
cecf4864 PM |
343 | |
344 | bus = top; | |
d71374da | 345 | down_read(&pci_bus_sem); |
cecf4864 PM |
346 | next = top->devices.next; |
347 | for (;;) { | |
348 | if (next == &bus->devices) { | |
349 | /* end of this bus, go up or finish */ | |
350 | if (bus == top) | |
351 | break; | |
352 | next = bus->self->bus_list.next; | |
353 | bus = bus->self->bus; | |
354 | continue; | |
355 | } | |
356 | dev = list_entry(next, struct pci_dev, bus_list); | |
cecf4864 PM |
357 | if (dev->subordinate) { |
358 | /* this is a pci-pci bridge, do its devices next */ | |
359 | next = dev->subordinate->devices.next; | |
360 | bus = dev->subordinate; | |
361 | } else | |
362 | next = dev->bus_list.next; | |
cecf4864 | 363 | |
d71374da | 364 | /* Run device routines with the device locked */ |
8e9394ce | 365 | device_lock(&dev->dev); |
70298c6e | 366 | retval = cb(dev, userdata); |
8e9394ce | 367 | device_unlock(&dev->dev); |
70298c6e ZY |
368 | if (retval) |
369 | break; | |
cecf4864 | 370 | } |
d71374da | 371 | up_read(&pci_bus_sem); |
cecf4864 | 372 | } |
7c94def8 | 373 | EXPORT_SYMBOL_GPL(pci_walk_bus); |
cecf4864 | 374 | |
1da177e4 LT |
375 | EXPORT_SYMBOL(pci_bus_alloc_resource); |
376 | EXPORT_SYMBOL_GPL(pci_bus_add_device); | |
377 | EXPORT_SYMBOL(pci_bus_add_devices); | |
378 | EXPORT_SYMBOL(pci_enable_bridges); |