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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>
17#include <linux/slab.h>
18
19#include "pci.h"
20
21void 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
37struct 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}
51EXPORT_SYMBOL_GPL(pci_bus_resource_n);
52
53void 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++)
59 bus->resource[i] = NULL;
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
67/**
68 * pci_bus_alloc_resource - allocate a resource from a parent bus
69 * @bus: PCI bus
70 * @res: resource to allocate
71 * @size: size of resource to allocate
72 * @align: alignment of resource to allocate
73 * @min: minimum /proc/iomem address to allocate
74 * @type_mask: IORESOURCE_* type flags
75 * @alignf: resource alignment function
76 * @alignf_data: data argument for resource alignment function
77 *
78 * Given the PCI bus a device resides on, the size, minimum address,
79 * alignment and type, try to find an acceptable resource allocation
80 * for a specific device resource.
81 */
82int
83pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
84 resource_size_t size, resource_size_t align,
85 resource_size_t min, unsigned int type_mask,
86 resource_size_t (*alignf)(void *,
87 const struct resource *,
88 resource_size_t,
89 resource_size_t),
90 void *alignf_data)
91{
92 int i, ret = -ENOMEM;
93 struct resource *r;
94 resource_size_t max = -1;
95
96 type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
97
98 /* don't allocate too high if the pref mem doesn't support 64bit*/
99 if (!(res->flags & IORESOURCE_MEM_64))
100 max = PCIBIOS_MAX_MEM_32;
101
102 pci_bus_for_each_resource(bus, r, i) {
103 if (!r)
104 continue;
105
106 /* type_mask must match */
107 if ((res->flags ^ r->flags) & type_mask)
108 continue;
109
110 /* We cannot allocate a non-prefetching resource
111 from a pre-fetching area */
112 if ((r->flags & IORESOURCE_PREFETCH) &&
113 !(res->flags & IORESOURCE_PREFETCH))
114 continue;
115
116 /* Ok, try it out.. */
117 ret = allocate_resource(r, res, size,
118 r->start ? : min,
119 max, align,
120 alignf, alignf_data);
121 if (ret == 0)
122 break;
123 }
124 return ret;
125}
126
127/**
128 * pci_bus_add_device - add a single device
129 * @dev: device to add
130 *
131 * This adds a single pci device to the global
132 * device list and adds sysfs and procfs entries
133 */
134int pci_bus_add_device(struct pci_dev *dev)
135{
136 int retval;
137 retval = device_add(&dev->dev);
138 if (retval)
139 return retval;
140
141 dev->is_added = 1;
142 pci_proc_attach_device(dev);
143 pci_create_sysfs_dev_files(dev);
144 return 0;
145}
146
147/**
148 * pci_bus_add_child - add a child bus
149 * @bus: bus to add
150 *
151 * This adds sysfs entries for a single bus
152 */
153int pci_bus_add_child(struct pci_bus *bus)
154{
155 int retval;
156
157 if (bus->bridge)
158 bus->dev.parent = bus->bridge;
159
160 retval = device_register(&bus->dev);
161 if (retval)
162 return retval;
163
164 bus->is_added = 1;
165
166 /* Create legacy_io and legacy_mem files for this bus */
167 pci_create_legacy_files(bus);
168
169 return retval;
170}
171
172/**
173 * pci_bus_add_devices - insert newly discovered PCI devices
174 * @bus: bus to check for new devices
175 *
176 * Add newly discovered PCI devices (which are on the bus->devices
177 * list) to the global PCI device list, add the sysfs and procfs
178 * entries. Where a bridge is found, add the discovered bus to
179 * the parents list of child buses, and recurse (breadth-first
180 * to be compatible with 2.4)
181 *
182 * Call hotplug for each new devices.
183 */
184void pci_bus_add_devices(const struct pci_bus *bus)
185{
186 struct pci_dev *dev;
187 struct pci_bus *child;
188 int retval;
189
190 list_for_each_entry(dev, &bus->devices, bus_list) {
191 /* Skip already-added devices */
192 if (dev->is_added)
193 continue;
194 retval = pci_bus_add_device(dev);
195 if (retval)
196 dev_err(&dev->dev, "Error adding device, continuing\n");
197 }
198
199 list_for_each_entry(dev, &bus->devices, bus_list) {
200 BUG_ON(!dev->is_added);
201
202 child = dev->subordinate;
203 /*
204 * If there is an unattached subordinate bus, attach
205 * it and then scan for unattached PCI devices.
206 */
207 if (!child)
208 continue;
209 if (list_empty(&child->node)) {
210 down_write(&pci_bus_sem);
211 list_add_tail(&child->node, &dev->bus->children);
212 up_write(&pci_bus_sem);
213 }
214 pci_bus_add_devices(child);
215
216 /*
217 * register the bus with sysfs as the parent is now
218 * properly registered.
219 */
220 if (child->is_added)
221 continue;
222 retval = pci_bus_add_child(child);
223 if (retval)
224 dev_err(&dev->dev, "Error adding bus, continuing\n");
225 }
226}
227
228void pci_enable_bridges(struct pci_bus *bus)
229{
230 struct pci_dev *dev;
231 int retval;
232
233 list_for_each_entry(dev, &bus->devices, bus_list) {
234 if (dev->subordinate) {
235 if (!pci_is_enabled(dev)) {
236 retval = pci_enable_device(dev);
237 if (retval)
238 dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n", retval);
239 pci_set_master(dev);
240 }
241 pci_enable_bridges(dev->subordinate);
242 }
243 }
244}
245
246/** pci_walk_bus - walk devices on/under bus, calling callback.
247 * @top bus whose devices should be walked
248 * @cb callback to be called for each device found
249 * @userdata arbitrary pointer to be passed to callback.
250 *
251 * Walk the given bus, including any bridged devices
252 * on buses under this bus. Call the provided callback
253 * on each device found.
254 *
255 * We check the return of @cb each time. If it returns anything
256 * other than 0, we break out.
257 *
258 */
259void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
260 void *userdata)
261{
262 struct pci_dev *dev;
263 struct pci_bus *bus;
264 struct list_head *next;
265 int retval;
266
267 bus = top;
268 down_read(&pci_bus_sem);
269 next = top->devices.next;
270 for (;;) {
271 if (next == &bus->devices) {
272 /* end of this bus, go up or finish */
273 if (bus == top)
274 break;
275 next = bus->self->bus_list.next;
276 bus = bus->self->bus;
277 continue;
278 }
279 dev = list_entry(next, struct pci_dev, bus_list);
280 if (dev->subordinate) {
281 /* this is a pci-pci bridge, do its devices next */
282 next = dev->subordinate->devices.next;
283 bus = dev->subordinate;
284 } else
285 next = dev->bus_list.next;
286
287 /* Run device routines with the device locked */
288 device_lock(&dev->dev);
289 retval = cb(dev, userdata);
290 device_unlock(&dev->dev);
291 if (retval)
292 break;
293 }
294 up_read(&pci_bus_sem);
295}
296EXPORT_SYMBOL_GPL(pci_walk_bus);
297
298EXPORT_SYMBOL(pci_bus_alloc_resource);
299EXPORT_SYMBOL_GPL(pci_bus_add_device);
300EXPORT_SYMBOL(pci_bus_add_devices);
301EXPORT_SYMBOL(pci_enable_bridges);
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/slab.h>
17
18#include "pci.h"
19
20void pci_add_resource_offset(struct list_head *resources, struct resource *res,
21 resource_size_t offset)
22{
23 struct resource_entry *entry;
24
25 entry = resource_list_create_entry(res, 0);
26 if (!entry) {
27 printk(KERN_ERR "PCI: can't add host bridge window %pR\n", res);
28 return;
29 }
30
31 entry->offset = offset;
32 resource_list_add_tail(entry, resources);
33}
34EXPORT_SYMBOL(pci_add_resource_offset);
35
36void pci_add_resource(struct list_head *resources, struct resource *res)
37{
38 pci_add_resource_offset(resources, res, 0);
39}
40EXPORT_SYMBOL(pci_add_resource);
41
42void pci_free_resource_list(struct list_head *resources)
43{
44 resource_list_free(resources);
45}
46EXPORT_SYMBOL(pci_free_resource_list);
47
48void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,
49 unsigned int flags)
50{
51 struct pci_bus_resource *bus_res;
52
53 bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
54 if (!bus_res) {
55 dev_err(&bus->dev, "can't add %pR resource\n", res);
56 return;
57 }
58
59 bus_res->res = res;
60 bus_res->flags = flags;
61 list_add_tail(&bus_res->list, &bus->resources);
62}
63
64struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n)
65{
66 struct pci_bus_resource *bus_res;
67
68 if (n < PCI_BRIDGE_RESOURCE_NUM)
69 return bus->resource[n];
70
71 n -= PCI_BRIDGE_RESOURCE_NUM;
72 list_for_each_entry(bus_res, &bus->resources, list) {
73 if (n-- == 0)
74 return bus_res->res;
75 }
76 return NULL;
77}
78EXPORT_SYMBOL_GPL(pci_bus_resource_n);
79
80void pci_bus_remove_resources(struct pci_bus *bus)
81{
82 int i;
83 struct pci_bus_resource *bus_res, *tmp;
84
85 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
86 bus->resource[i] = NULL;
87
88 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
89 list_del(&bus_res->list);
90 kfree(bus_res);
91 }
92}
93
94static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
95#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
96static struct pci_bus_region pci_64_bit = {0,
97 (pci_bus_addr_t) 0xffffffffffffffffULL};
98static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL,
99 (pci_bus_addr_t) 0xffffffffffffffffULL};
100#endif
101
102/*
103 * @res contains CPU addresses. Clip it so the corresponding bus addresses
104 * on @bus are entirely within @region. This is used to control the bus
105 * addresses of resources we allocate, e.g., we may need a resource that
106 * can be mapped by a 32-bit BAR.
107 */
108static void pci_clip_resource_to_region(struct pci_bus *bus,
109 struct resource *res,
110 struct pci_bus_region *region)
111{
112 struct pci_bus_region r;
113
114 pcibios_resource_to_bus(bus, &r, res);
115 if (r.start < region->start)
116 r.start = region->start;
117 if (r.end > region->end)
118 r.end = region->end;
119
120 if (r.end < r.start)
121 res->end = res->start - 1;
122 else
123 pcibios_bus_to_resource(bus, res, &r);
124}
125
126static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,
127 resource_size_t size, resource_size_t align,
128 resource_size_t min, unsigned long type_mask,
129 resource_size_t (*alignf)(void *,
130 const struct resource *,
131 resource_size_t,
132 resource_size_t),
133 void *alignf_data,
134 struct pci_bus_region *region)
135{
136 int i, ret;
137 struct resource *r, avail;
138 resource_size_t max;
139
140 type_mask |= IORESOURCE_TYPE_BITS;
141
142 pci_bus_for_each_resource(bus, r, i) {
143 resource_size_t min_used = min;
144
145 if (!r)
146 continue;
147
148 /* type_mask must match */
149 if ((res->flags ^ r->flags) & type_mask)
150 continue;
151
152 /* We cannot allocate a non-prefetching resource
153 from a pre-fetching area */
154 if ((r->flags & IORESOURCE_PREFETCH) &&
155 !(res->flags & IORESOURCE_PREFETCH))
156 continue;
157
158 avail = *r;
159 pci_clip_resource_to_region(bus, &avail, region);
160
161 /*
162 * "min" is typically PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM to
163 * protect badly documented motherboard resources, but if
164 * this is an already-configured bridge window, its start
165 * overrides "min".
166 */
167 if (avail.start)
168 min_used = avail.start;
169
170 max = avail.end;
171
172 /* Ok, try it out.. */
173 ret = allocate_resource(r, res, size, min_used, max,
174 align, alignf, alignf_data);
175 if (ret == 0)
176 return 0;
177 }
178 return -ENOMEM;
179}
180
181/**
182 * pci_bus_alloc_resource - allocate a resource from a parent bus
183 * @bus: PCI bus
184 * @res: resource to allocate
185 * @size: size of resource to allocate
186 * @align: alignment of resource to allocate
187 * @min: minimum /proc/iomem address to allocate
188 * @type_mask: IORESOURCE_* type flags
189 * @alignf: resource alignment function
190 * @alignf_data: data argument for resource alignment function
191 *
192 * Given the PCI bus a device resides on, the size, minimum address,
193 * alignment and type, try to find an acceptable resource allocation
194 * for a specific device resource.
195 */
196int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
197 resource_size_t size, resource_size_t align,
198 resource_size_t min, unsigned long type_mask,
199 resource_size_t (*alignf)(void *,
200 const struct resource *,
201 resource_size_t,
202 resource_size_t),
203 void *alignf_data)
204{
205#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
206 int rc;
207
208 if (res->flags & IORESOURCE_MEM_64) {
209 rc = pci_bus_alloc_from_region(bus, res, size, align, min,
210 type_mask, alignf, alignf_data,
211 &pci_high);
212 if (rc == 0)
213 return 0;
214
215 return pci_bus_alloc_from_region(bus, res, size, align, min,
216 type_mask, alignf, alignf_data,
217 &pci_64_bit);
218 }
219#endif
220
221 return pci_bus_alloc_from_region(bus, res, size, align, min,
222 type_mask, alignf, alignf_data,
223 &pci_32_bit);
224}
225EXPORT_SYMBOL(pci_bus_alloc_resource);
226
227/*
228 * The @idx resource of @dev should be a PCI-PCI bridge window. If this
229 * resource fits inside a window of an upstream bridge, do nothing. If it
230 * overlaps an upstream window but extends outside it, clip the resource so
231 * it fits completely inside.
232 */
233bool pci_bus_clip_resource(struct pci_dev *dev, int idx)
234{
235 struct pci_bus *bus = dev->bus;
236 struct resource *res = &dev->resource[idx];
237 struct resource orig_res = *res;
238 struct resource *r;
239 int i;
240
241 pci_bus_for_each_resource(bus, r, i) {
242 resource_size_t start, end;
243
244 if (!r)
245 continue;
246
247 if (resource_type(res) != resource_type(r))
248 continue;
249
250 start = max(r->start, res->start);
251 end = min(r->end, res->end);
252
253 if (start > end)
254 continue; /* no overlap */
255
256 if (res->start == start && res->end == end)
257 return false; /* no change */
258
259 res->start = start;
260 res->end = end;
261 res->flags &= ~IORESOURCE_UNSET;
262 orig_res.flags &= ~IORESOURCE_UNSET;
263 dev_printk(KERN_DEBUG, &dev->dev, "%pR clipped to %pR\n",
264 &orig_res, res);
265
266 return true;
267 }
268
269 return false;
270}
271
272void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
273
274void __weak pcibios_bus_add_device(struct pci_dev *pdev) { }
275
276/**
277 * pci_bus_add_device - start driver for a single device
278 * @dev: device to add
279 *
280 * This adds add sysfs entries and start device drivers
281 */
282void pci_bus_add_device(struct pci_dev *dev)
283{
284 int retval;
285
286 /*
287 * Can not put in pci_device_add yet because resources
288 * are not assigned yet for some devices.
289 */
290 pcibios_bus_add_device(dev);
291 pci_fixup_device(pci_fixup_final, dev);
292 pci_create_sysfs_dev_files(dev);
293 pci_proc_attach_device(dev);
294
295 dev->match_driver = true;
296 retval = device_attach(&dev->dev);
297 if (retval < 0 && retval != -EPROBE_DEFER) {
298 dev_warn(&dev->dev, "device attach failed (%d)\n", retval);
299 pci_proc_detach_device(dev);
300 pci_remove_sysfs_dev_files(dev);
301 return;
302 }
303
304 dev->is_added = 1;
305}
306EXPORT_SYMBOL_GPL(pci_bus_add_device);
307
308/**
309 * pci_bus_add_devices - start driver for PCI devices
310 * @bus: bus to check for new devices
311 *
312 * Start driver for PCI devices and add some sysfs entries.
313 */
314void pci_bus_add_devices(const struct pci_bus *bus)
315{
316 struct pci_dev *dev;
317 struct pci_bus *child;
318
319 list_for_each_entry(dev, &bus->devices, bus_list) {
320 /* Skip already-added devices */
321 if (dev->is_added)
322 continue;
323 pci_bus_add_device(dev);
324 }
325
326 list_for_each_entry(dev, &bus->devices, bus_list) {
327 /* Skip if device attach failed */
328 if (!dev->is_added)
329 continue;
330 child = dev->subordinate;
331 if (child)
332 pci_bus_add_devices(child);
333 }
334}
335EXPORT_SYMBOL(pci_bus_add_devices);
336
337/** pci_walk_bus - walk devices on/under bus, calling callback.
338 * @top bus whose devices should be walked
339 * @cb callback to be called for each device found
340 * @userdata arbitrary pointer to be passed to callback.
341 *
342 * Walk the given bus, including any bridged devices
343 * on buses under this bus. Call the provided callback
344 * on each device found.
345 *
346 * We check the return of @cb each time. If it returns anything
347 * other than 0, we break out.
348 *
349 */
350void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
351 void *userdata)
352{
353 struct pci_dev *dev;
354 struct pci_bus *bus;
355 struct list_head *next;
356 int retval;
357
358 bus = top;
359 down_read(&pci_bus_sem);
360 next = top->devices.next;
361 for (;;) {
362 if (next == &bus->devices) {
363 /* end of this bus, go up or finish */
364 if (bus == top)
365 break;
366 next = bus->self->bus_list.next;
367 bus = bus->self->bus;
368 continue;
369 }
370 dev = list_entry(next, struct pci_dev, bus_list);
371 if (dev->subordinate) {
372 /* this is a pci-pci bridge, do its devices next */
373 next = dev->subordinate->devices.next;
374 bus = dev->subordinate;
375 } else
376 next = dev->bus_list.next;
377
378 retval = cb(dev, userdata);
379 if (retval)
380 break;
381 }
382 up_read(&pci_bus_sem);
383}
384EXPORT_SYMBOL_GPL(pci_walk_bus);
385
386struct pci_bus *pci_bus_get(struct pci_bus *bus)
387{
388 if (bus)
389 get_device(&bus->dev);
390 return bus;
391}
392EXPORT_SYMBOL(pci_bus_get);
393
394void pci_bus_put(struct pci_bus *bus)
395{
396 if (bus)
397 put_device(&bus->dev);
398}
399EXPORT_SYMBOL(pci_bus_put);
400