1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * From setup-res.c, by:
4 * Dave Rusling (david.rusling@reo.mts.dec.com)
5 * David Mosberger (davidm@cs.arizona.edu)
6 * David Miller (davem@redhat.com)
7 * Ivan Kokshaysky (ink@jurassic.park.msu.ru)
8 */
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/pci.h>
12 #include <linux/errno.h>
13 #include <linux/ioport.h>
14 #include <linux/proc_fs.h>
15 #include <linux/slab.h>
16
17 #include "pci.h"
18
pci_add_resource_offset(struct list_head * resources,struct resource * res,resource_size_t offset)19 void pci_add_resource_offset(struct list_head *resources, struct resource *res,
20 resource_size_t offset)
21 {
22 struct resource_entry *entry;
23
24 entry = resource_list_create_entry(res, 0);
25 if (!entry) {
26 pr_err("PCI: can't add host bridge window %pR\n", res);
27 return;
28 }
29
30 entry->offset = offset;
31 resource_list_add_tail(entry, resources);
32 }
33 EXPORT_SYMBOL(pci_add_resource_offset);
34
pci_add_resource(struct list_head * resources,struct resource * res)35 void pci_add_resource(struct list_head *resources, struct resource *res)
36 {
37 pci_add_resource_offset(resources, res, 0);
38 }
39 EXPORT_SYMBOL(pci_add_resource);
40
pci_free_resource_list(struct list_head * resources)41 void pci_free_resource_list(struct list_head *resources)
42 {
43 resource_list_free(resources);
44 }
45 EXPORT_SYMBOL(pci_free_resource_list);
46
pci_bus_add_resource(struct pci_bus * bus,struct resource * res,unsigned int flags)47 void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,
48 unsigned int flags)
49 {
50 struct pci_bus_resource *bus_res;
51
52 bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
53 if (!bus_res) {
54 dev_err(&bus->dev, "can't add %pR resource\n", res);
55 return;
56 }
57
58 bus_res->res = res;
59 bus_res->flags = flags;
60 list_add_tail(&bus_res->list, &bus->resources);
61 }
62
pci_bus_resource_n(const struct pci_bus * bus,int n)63 struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n)
64 {
65 struct pci_bus_resource *bus_res;
66
67 if (n < PCI_BRIDGE_RESOURCE_NUM)
68 return bus->resource[n];
69
70 n -= PCI_BRIDGE_RESOURCE_NUM;
71 list_for_each_entry(bus_res, &bus->resources, list) {
72 if (n-- == 0)
73 return bus_res->res;
74 }
75 return NULL;
76 }
77 EXPORT_SYMBOL_GPL(pci_bus_resource_n);
78
pci_bus_remove_resources(struct pci_bus * bus)79 void pci_bus_remove_resources(struct pci_bus *bus)
80 {
81 int i;
82 struct pci_bus_resource *bus_res, *tmp;
83
84 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
85 bus->resource[i] = NULL;
86
87 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
88 list_del(&bus_res->list);
89 kfree(bus_res);
90 }
91 }
92
devm_request_pci_bus_resources(struct device * dev,struct list_head * resources)93 int devm_request_pci_bus_resources(struct device *dev,
94 struct list_head *resources)
95 {
96 struct resource_entry *win;
97 struct resource *parent, *res;
98 int err;
99
100 resource_list_for_each_entry(win, resources) {
101 res = win->res;
102 switch (resource_type(res)) {
103 case IORESOURCE_IO:
104 parent = &ioport_resource;
105 break;
106 case IORESOURCE_MEM:
107 parent = &iomem_resource;
108 break;
109 default:
110 continue;
111 }
112
113 err = devm_request_resource(dev, parent, res);
114 if (err)
115 return err;
116 }
117
118 return 0;
119 }
120 EXPORT_SYMBOL_GPL(devm_request_pci_bus_resources);
121
122 static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
123 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
124 static struct pci_bus_region pci_64_bit = {0,
125 (pci_bus_addr_t) 0xffffffffffffffffULL};
126 static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL,
127 (pci_bus_addr_t) 0xffffffffffffffffULL};
128 #endif
129
130 /*
131 * @res contains CPU addresses. Clip it so the corresponding bus addresses
132 * on @bus are entirely within @region. This is used to control the bus
133 * addresses of resources we allocate, e.g., we may need a resource that
134 * can be mapped by a 32-bit BAR.
135 */
pci_clip_resource_to_region(struct pci_bus * bus,struct resource * res,struct pci_bus_region * region)136 static void pci_clip_resource_to_region(struct pci_bus *bus,
137 struct resource *res,
138 struct pci_bus_region *region)
139 {
140 struct pci_bus_region r;
141
142 pcibios_resource_to_bus(bus, &r, res);
143 if (r.start < region->start)
144 r.start = region->start;
145 if (r.end > region->end)
146 r.end = region->end;
147
148 if (r.end < r.start)
149 res->end = res->start - 1;
150 else
151 pcibios_bus_to_resource(bus, res, &r);
152 }
153
pci_bus_alloc_from_region(struct pci_bus * bus,struct resource * res,resource_size_t size,resource_size_t align,resource_size_t min,unsigned long type_mask,resource_size_t (* alignf)(void *,const struct resource *,resource_size_t,resource_size_t),void * alignf_data,struct pci_bus_region * region)154 static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,
155 resource_size_t size, resource_size_t align,
156 resource_size_t min, unsigned long type_mask,
157 resource_size_t (*alignf)(void *,
158 const struct resource *,
159 resource_size_t,
160 resource_size_t),
161 void *alignf_data,
162 struct pci_bus_region *region)
163 {
164 int i, ret;
165 struct resource *r, avail;
166 resource_size_t max;
167
168 type_mask |= IORESOURCE_TYPE_BITS;
169
170 pci_bus_for_each_resource(bus, r, i) {
171 resource_size_t min_used = min;
172
173 if (!r)
174 continue;
175
176 /* type_mask must match */
177 if ((res->flags ^ r->flags) & type_mask)
178 continue;
179
180 /* We cannot allocate a non-prefetching resource
181 from a pre-fetching area */
182 if ((r->flags & IORESOURCE_PREFETCH) &&
183 !(res->flags & IORESOURCE_PREFETCH))
184 continue;
185
186 avail = *r;
187 pci_clip_resource_to_region(bus, &avail, region);
188
189 /*
190 * "min" is typically PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM to
191 * protect badly documented motherboard resources, but if
192 * this is an already-configured bridge window, its start
193 * overrides "min".
194 */
195 if (avail.start)
196 min_used = avail.start;
197
198 max = avail.end;
199
200 /* Ok, try it out.. */
201 ret = allocate_resource(r, res, size, min_used, max,
202 align, alignf, alignf_data);
203 if (ret == 0)
204 return 0;
205 }
206 return -ENOMEM;
207 }
208
209 /**
210 * pci_bus_alloc_resource - allocate a resource from a parent bus
211 * @bus: PCI bus
212 * @res: resource to allocate
213 * @size: size of resource to allocate
214 * @align: alignment of resource to allocate
215 * @min: minimum /proc/iomem address to allocate
216 * @type_mask: IORESOURCE_* type flags
217 * @alignf: resource alignment function
218 * @alignf_data: data argument for resource alignment function
219 *
220 * Given the PCI bus a device resides on, the size, minimum address,
221 * alignment and type, try to find an acceptable resource allocation
222 * for a specific device resource.
223 */
pci_bus_alloc_resource(struct pci_bus * bus,struct resource * res,resource_size_t size,resource_size_t align,resource_size_t min,unsigned long type_mask,resource_size_t (* alignf)(void *,const struct resource *,resource_size_t,resource_size_t),void * alignf_data)224 int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
225 resource_size_t size, resource_size_t align,
226 resource_size_t min, unsigned long type_mask,
227 resource_size_t (*alignf)(void *,
228 const struct resource *,
229 resource_size_t,
230 resource_size_t),
231 void *alignf_data)
232 {
233 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
234 int rc;
235
236 if (res->flags & IORESOURCE_MEM_64) {
237 rc = pci_bus_alloc_from_region(bus, res, size, align, min,
238 type_mask, alignf, alignf_data,
239 &pci_high);
240 if (rc == 0)
241 return 0;
242
243 return pci_bus_alloc_from_region(bus, res, size, align, min,
244 type_mask, alignf, alignf_data,
245 &pci_64_bit);
246 }
247 #endif
248
249 return pci_bus_alloc_from_region(bus, res, size, align, min,
250 type_mask, alignf, alignf_data,
251 &pci_32_bit);
252 }
253 EXPORT_SYMBOL(pci_bus_alloc_resource);
254
255 /*
256 * The @idx resource of @dev should be a PCI-PCI bridge window. If this
257 * resource fits inside a window of an upstream bridge, do nothing. If it
258 * overlaps an upstream window but extends outside it, clip the resource so
259 * it fits completely inside.
260 */
pci_bus_clip_resource(struct pci_dev * dev,int idx)261 bool pci_bus_clip_resource(struct pci_dev *dev, int idx)
262 {
263 struct pci_bus *bus = dev->bus;
264 struct resource *res = &dev->resource[idx];
265 struct resource orig_res = *res;
266 struct resource *r;
267 int i;
268
269 pci_bus_for_each_resource(bus, r, i) {
270 resource_size_t start, end;
271
272 if (!r)
273 continue;
274
275 if (resource_type(res) != resource_type(r))
276 continue;
277
278 start = max(r->start, res->start);
279 end = min(r->end, res->end);
280
281 if (start > end)
282 continue; /* no overlap */
283
284 if (res->start == start && res->end == end)
285 return false; /* no change */
286
287 res->start = start;
288 res->end = end;
289 res->flags &= ~IORESOURCE_UNSET;
290 orig_res.flags &= ~IORESOURCE_UNSET;
291 pci_info(dev, "%pR clipped to %pR\n", &orig_res, res);
292
293 return true;
294 }
295
296 return false;
297 }
298
pcibios_resource_survey_bus(struct pci_bus * bus)299 void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
300
pcibios_bus_add_device(struct pci_dev * pdev)301 void __weak pcibios_bus_add_device(struct pci_dev *pdev) { }
302
303 /**
304 * pci_bus_add_device - start driver for a single device
305 * @dev: device to add
306 *
307 * This adds add sysfs entries and start device drivers
308 */
pci_bus_add_device(struct pci_dev * dev)309 void pci_bus_add_device(struct pci_dev *dev)
310 {
311 int retval;
312
313 /*
314 * Can not put in pci_device_add yet because resources
315 * are not assigned yet for some devices.
316 */
317 pcibios_bus_add_device(dev);
318 pci_fixup_device(pci_fixup_final, dev);
319 pci_create_sysfs_dev_files(dev);
320 pci_proc_attach_device(dev);
321 pci_bridge_d3_update(dev);
322
323 dev->match_driver = true;
324 retval = device_attach(&dev->dev);
325 if (retval < 0 && retval != -EPROBE_DEFER)
326 pci_warn(dev, "device attach failed (%d)\n", retval);
327
328 pci_dev_assign_added(dev, true);
329 }
330 EXPORT_SYMBOL_GPL(pci_bus_add_device);
331
332 /**
333 * pci_bus_add_devices - start driver for PCI devices
334 * @bus: bus to check for new devices
335 *
336 * Start driver for PCI devices and add some sysfs entries.
337 */
pci_bus_add_devices(const struct pci_bus * bus)338 void pci_bus_add_devices(const struct pci_bus *bus)
339 {
340 struct pci_dev *dev;
341 struct pci_bus *child;
342
343 list_for_each_entry(dev, &bus->devices, bus_list) {
344 /* Skip already-added devices */
345 if (pci_dev_is_added(dev))
346 continue;
347 pci_bus_add_device(dev);
348 }
349
350 list_for_each_entry(dev, &bus->devices, bus_list) {
351 /* Skip if device attach failed */
352 if (!pci_dev_is_added(dev))
353 continue;
354 child = dev->subordinate;
355 if (child)
356 pci_bus_add_devices(child);
357 }
358 }
359 EXPORT_SYMBOL(pci_bus_add_devices);
360
361 /** pci_walk_bus - walk devices on/under bus, calling callback.
362 * @top bus whose devices should be walked
363 * @cb callback to be called for each device found
364 * @userdata arbitrary pointer to be passed to callback.
365 *
366 * Walk the given bus, including any bridged devices
367 * on buses under this bus. Call the provided callback
368 * on each device found.
369 *
370 * We check the return of @cb each time. If it returns anything
371 * other than 0, we break out.
372 *
373 */
pci_walk_bus(struct pci_bus * top,int (* cb)(struct pci_dev *,void *),void * userdata)374 void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
375 void *userdata)
376 {
377 struct pci_dev *dev;
378 struct pci_bus *bus;
379 struct list_head *next;
380 int retval;
381
382 bus = top;
383 down_read(&pci_bus_sem);
384 next = top->devices.next;
385 for (;;) {
386 if (next == &bus->devices) {
387 /* end of this bus, go up or finish */
388 if (bus == top)
389 break;
390 next = bus->self->bus_list.next;
391 bus = bus->self->bus;
392 continue;
393 }
394 dev = list_entry(next, struct pci_dev, bus_list);
395 if (dev->subordinate) {
396 /* this is a pci-pci bridge, do its devices next */
397 next = dev->subordinate->devices.next;
398 bus = dev->subordinate;
399 } else
400 next = dev->bus_list.next;
401
402 retval = cb(dev, userdata);
403 if (retval)
404 break;
405 }
406 up_read(&pci_bus_sem);
407 }
408 EXPORT_SYMBOL_GPL(pci_walk_bus);
409
pci_bus_get(struct pci_bus * bus)410 struct pci_bus *pci_bus_get(struct pci_bus *bus)
411 {
412 if (bus)
413 get_device(&bus->dev);
414 return bus;
415 }
416 EXPORT_SYMBOL(pci_bus_get);
417
pci_bus_put(struct pci_bus * bus)418 void pci_bus_put(struct pci_bus *bus)
419 {
420 if (bus)
421 put_device(&bus->dev);
422 }
423 EXPORT_SYMBOL(pci_bus_put);
424