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/of.h>
15#include <linux/of_platform.h>
16#include <linux/platform_device.h>
17#include <linux/proc_fs.h>
18#include <linux/slab.h>
19
20#include "pci.h"
21
22/*
23 * The first PCI_BRIDGE_RESOURCE_NUM PCI bus resources (those that correspond
24 * to P2P or CardBus bridge windows) go in a table. Additional ones (for
25 * buses below host bridges or subtractive decode bridges) go in the list.
26 * Use pci_bus_for_each_resource() to iterate through all the resources.
27 */
28
29struct pci_bus_resource {
30 struct list_head list;
31 struct resource *res;
32};
33
34void pci_add_resource_offset(struct list_head *resources, struct resource *res,
35 resource_size_t offset)
36{
37 struct resource_entry *entry;
38
39 entry = resource_list_create_entry(res, extra_size: 0);
40 if (!entry) {
41 pr_err("PCI: can't add host bridge window %pR\n", res);
42 return;
43 }
44
45 entry->offset = offset;
46 resource_list_add_tail(entry, head: resources);
47}
48EXPORT_SYMBOL(pci_add_resource_offset);
49
50void pci_add_resource(struct list_head *resources, struct resource *res)
51{
52 pci_add_resource_offset(resources, res, 0);
53}
54EXPORT_SYMBOL(pci_add_resource);
55
56void pci_free_resource_list(struct list_head *resources)
57{
58 resource_list_free(head: resources);
59}
60EXPORT_SYMBOL(pci_free_resource_list);
61
62void pci_bus_add_resource(struct pci_bus *bus, struct resource *res)
63{
64 struct pci_bus_resource *bus_res;
65
66 bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
67 if (!bus_res) {
68 dev_err(&bus->dev, "can't add %pR resource\n", res);
69 return;
70 }
71
72 bus_res->res = res;
73 list_add_tail(new: &bus_res->list, head: &bus->resources);
74}
75
76struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n)
77{
78 struct pci_bus_resource *bus_res;
79
80 if (n < PCI_BRIDGE_RESOURCE_NUM)
81 return bus->resource[n];
82
83 n -= PCI_BRIDGE_RESOURCE_NUM;
84 list_for_each_entry(bus_res, &bus->resources, list) {
85 if (n-- == 0)
86 return bus_res->res;
87 }
88 return NULL;
89}
90EXPORT_SYMBOL_GPL(pci_bus_resource_n);
91
92void pci_bus_remove_resource(struct pci_bus *bus, struct resource *res)
93{
94 struct pci_bus_resource *bus_res, *tmp;
95 int i;
96
97 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
98 if (bus->resource[i] == res) {
99 bus->resource[i] = NULL;
100 return;
101 }
102 }
103
104 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
105 if (bus_res->res == res) {
106 list_del(entry: &bus_res->list);
107 kfree(objp: bus_res);
108 return;
109 }
110 }
111}
112
113void pci_bus_remove_resources(struct pci_bus *bus)
114{
115 int i;
116 struct pci_bus_resource *bus_res, *tmp;
117
118 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
119 bus->resource[i] = NULL;
120
121 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
122 list_del(entry: &bus_res->list);
123 kfree(objp: bus_res);
124 }
125}
126
127int devm_request_pci_bus_resources(struct device *dev,
128 struct list_head *resources)
129{
130 struct resource_entry *win;
131 struct resource *parent, *res;
132 int err;
133
134 resource_list_for_each_entry(win, resources) {
135 res = win->res;
136 switch (resource_type(res)) {
137 case IORESOURCE_IO:
138 parent = &ioport_resource;
139 break;
140 case IORESOURCE_MEM:
141 parent = &iomem_resource;
142 break;
143 default:
144 continue;
145 }
146
147 err = devm_request_resource(dev, root: parent, new: res);
148 if (err)
149 return err;
150 }
151
152 return 0;
153}
154EXPORT_SYMBOL_GPL(devm_request_pci_bus_resources);
155
156static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
157#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
158static struct pci_bus_region pci_64_bit = {0,
159 (pci_bus_addr_t) 0xffffffffffffffffULL};
160static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL,
161 (pci_bus_addr_t) 0xffffffffffffffffULL};
162#endif
163
164/*
165 * @res contains CPU addresses. Clip it so the corresponding bus addresses
166 * on @bus are entirely within @region. This is used to control the bus
167 * addresses of resources we allocate, e.g., we may need a resource that
168 * can be mapped by a 32-bit BAR.
169 */
170static void pci_clip_resource_to_region(struct pci_bus *bus,
171 struct resource *res,
172 struct pci_bus_region *region)
173{
174 struct pci_bus_region r;
175
176 pcibios_resource_to_bus(bus, region: &r, res);
177 if (r.start < region->start)
178 r.start = region->start;
179 if (r.end > region->end)
180 r.end = region->end;
181
182 if (r.end < r.start)
183 res->end = res->start - 1;
184 else
185 pcibios_bus_to_resource(bus, res, region: &r);
186}
187
188static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,
189 resource_size_t size, resource_size_t align,
190 resource_size_t min, unsigned long type_mask,
191 resource_alignf alignf,
192 void *alignf_data,
193 struct pci_bus_region *region)
194{
195 struct resource *r, avail;
196 resource_size_t max;
197 int ret;
198
199 type_mask |= IORESOURCE_TYPE_BITS;
200
201 pci_bus_for_each_resource(bus, r) {
202 resource_size_t min_used = min;
203
204 if (!r)
205 continue;
206
207 if (r->flags & (IORESOURCE_UNSET|IORESOURCE_DISABLED))
208 continue;
209
210 /* type_mask must match */
211 if ((res->flags ^ r->flags) & type_mask)
212 continue;
213
214 /* We cannot allocate a non-prefetching resource
215 from a pre-fetching area */
216 if ((r->flags & IORESOURCE_PREFETCH) &&
217 !(res->flags & IORESOURCE_PREFETCH))
218 continue;
219
220 avail = *r;
221 pci_clip_resource_to_region(bus, res: &avail, region);
222
223 /*
224 * "min" is typically PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM to
225 * protect badly documented motherboard resources, but if
226 * this is an already-configured bridge window, its start
227 * overrides "min".
228 */
229 if (avail.start)
230 min_used = avail.start;
231
232 max = avail.end;
233
234 /* Don't bother if available space isn't large enough */
235 if (size > max - min_used + 1)
236 continue;
237
238 /* Ok, try it out.. */
239 ret = allocate_resource(root: r, new: res, size, min: min_used, max,
240 align, alignf, alignf_data);
241 if (ret == 0)
242 return 0;
243 }
244 return -ENOMEM;
245}
246
247/**
248 * pci_bus_alloc_resource - allocate a resource from a parent bus
249 * @bus: PCI bus
250 * @res: resource to allocate
251 * @size: size of resource to allocate
252 * @align: alignment of resource to allocate
253 * @min: minimum /proc/iomem address to allocate
254 * @type_mask: IORESOURCE_* type flags
255 * @alignf: resource alignment function
256 * @alignf_data: data argument for resource alignment function
257 *
258 * Given the PCI bus a device resides on, the size, minimum address,
259 * alignment and type, try to find an acceptable resource allocation
260 * for a specific device resource.
261 */
262int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
263 resource_size_t size, resource_size_t align,
264 resource_size_t min, unsigned long type_mask,
265 resource_alignf alignf,
266 void *alignf_data)
267{
268#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
269 int rc;
270
271 if (res->flags & IORESOURCE_MEM_64) {
272 rc = pci_bus_alloc_from_region(bus, res, size, align, min,
273 type_mask, alignf, alignf_data,
274 region: &pci_high);
275 if (rc == 0)
276 return 0;
277
278 return pci_bus_alloc_from_region(bus, res, size, align, min,
279 type_mask, alignf, alignf_data,
280 region: &pci_64_bit);
281 }
282#endif
283
284 return pci_bus_alloc_from_region(bus, res, size, align, min,
285 type_mask, alignf, alignf_data,
286 region: &pci_32_bit);
287}
288EXPORT_SYMBOL(pci_bus_alloc_resource);
289
290/*
291 * The @idx resource of @dev should be a PCI-PCI bridge window. If this
292 * resource fits inside a window of an upstream bridge, do nothing. If it
293 * overlaps an upstream window but extends outside it, clip the resource so
294 * it fits completely inside.
295 */
296bool pci_bus_clip_resource(struct pci_dev *dev, int idx)
297{
298 struct pci_bus *bus = dev->bus;
299 struct resource *res = &dev->resource[idx];
300 struct resource orig_res = *res;
301 struct resource *r;
302
303 pci_bus_for_each_resource(bus, r) {
304 resource_size_t start, end;
305
306 if (!r)
307 continue;
308
309 if (resource_type(res) != resource_type(res: r))
310 continue;
311
312 start = max(r->start, res->start);
313 end = min(r->end, res->end);
314
315 if (start > end)
316 continue; /* no overlap */
317
318 if (res->start == start && res->end == end)
319 return false; /* no change */
320
321 res->start = start;
322 res->end = end;
323 res->flags &= ~IORESOURCE_UNSET;
324 orig_res.flags &= ~IORESOURCE_UNSET;
325 pci_info(dev, "%pR clipped to %pR\n", &orig_res, res);
326
327 return true;
328 }
329
330 return false;
331}
332
333void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
334
335void __weak pcibios_bus_add_device(struct pci_dev *pdev) { }
336
337/**
338 * pci_bus_add_device - start driver for a single device
339 * @dev: device to add
340 *
341 * This adds add sysfs entries and start device drivers
342 */
343void pci_bus_add_device(struct pci_dev *dev)
344{
345 struct device_node *dn = dev->dev.of_node;
346 struct platform_device *pdev;
347
348 /*
349 * Can not put in pci_device_add yet because resources
350 * are not assigned yet for some devices.
351 */
352 pcibios_bus_add_device(pdev: dev);
353 pci_fixup_device(pass: pci_fixup_final, dev);
354 if (pci_is_bridge(dev))
355 of_pci_make_dev_node(pdev: dev);
356 pci_create_sysfs_dev_files(pdev: dev);
357 pci_proc_attach_device(dev);
358 pci_bridge_d3_update(dev);
359
360 /*
361 * If the PCI device is associated with a pwrctrl device with a
362 * power supply, create a device link between the PCI device and
363 * pwrctrl device. This ensures that pwrctrl drivers are probed
364 * before PCI client drivers.
365 */
366 pdev = of_find_device_by_node(np: dn);
367 if (pdev) {
368 if (of_pci_supply_present(np: dn)) {
369 if (!device_link_add(consumer: &dev->dev, supplier: &pdev->dev,
370 DL_FLAG_AUTOREMOVE_CONSUMER)) {
371 pci_err(dev, "failed to add device link to power control device %s\n",
372 pdev->name);
373 }
374 }
375 put_device(dev: &pdev->dev);
376 }
377
378 if (!dn || of_device_is_available(device: dn))
379 pci_dev_allow_binding(dev);
380
381 device_initial_probe(dev: &dev->dev);
382
383 pci_dev_assign_added(dev);
384}
385EXPORT_SYMBOL_GPL(pci_bus_add_device);
386
387/**
388 * pci_bus_add_devices - start driver for PCI devices
389 * @bus: bus to check for new devices
390 *
391 * Start driver for PCI devices and add some sysfs entries.
392 */
393void pci_bus_add_devices(const struct pci_bus *bus)
394{
395 struct pci_dev *dev;
396 struct pci_bus *child;
397
398 list_for_each_entry(dev, &bus->devices, bus_list) {
399 /* Skip already-added devices */
400 if (pci_dev_is_added(dev))
401 continue;
402 pci_bus_add_device(dev);
403 }
404
405 list_for_each_entry(dev, &bus->devices, bus_list) {
406 /* Skip if device attach failed */
407 if (!pci_dev_is_added(dev))
408 continue;
409 child = dev->subordinate;
410 if (child)
411 pci_bus_add_devices(bus: child);
412 }
413}
414EXPORT_SYMBOL(pci_bus_add_devices);
415
416static int __pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
417 void *userdata)
418{
419 struct pci_dev *dev;
420 int ret = 0;
421
422 list_for_each_entry(dev, &top->devices, bus_list) {
423 ret = cb(dev, userdata);
424 if (ret)
425 break;
426 if (dev->subordinate) {
427 ret = __pci_walk_bus(top: dev->subordinate, cb, userdata);
428 if (ret)
429 break;
430 }
431 }
432 return ret;
433}
434
435/**
436 * pci_walk_bus - walk devices on/under bus, calling callback.
437 * @top: bus whose devices should be walked
438 * @cb: callback to be called for each device found
439 * @userdata: arbitrary pointer to be passed to callback
440 *
441 * Walk the given bus, including any bridged devices
442 * on buses under this bus. Call the provided callback
443 * on each device found.
444 *
445 * We check the return of @cb each time. If it returns anything
446 * other than 0, we break out.
447 */
448void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata)
449{
450 down_read(sem: &pci_bus_sem);
451 __pci_walk_bus(top, cb, userdata);
452 up_read(sem: &pci_bus_sem);
453}
454EXPORT_SYMBOL_GPL(pci_walk_bus);
455
456void pci_walk_bus_locked(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata)
457{
458 lockdep_assert_held(&pci_bus_sem);
459
460 __pci_walk_bus(top, cb, userdata);
461}
462
463struct pci_bus *pci_bus_get(struct pci_bus *bus)
464{
465 if (bus)
466 get_device(dev: &bus->dev);
467 return bus;
468}
469
470void pci_bus_put(struct pci_bus *bus)
471{
472 if (bus)
473 put_device(dev: &bus->dev);
474}
475