1 // SPDX-License-Identifier: GPL-2.0
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)
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>
19 void pci_add_resource_offset(struct list_head *resources, struct resource *res,
20 resource_size_t offset)
22 struct resource_entry *entry;
24 entry = resource_list_create_entry(res, 0);
26 pr_err("PCI: can't add host bridge window %pR\n", res);
30 entry->offset = offset;
31 resource_list_add_tail(entry, resources);
33 EXPORT_SYMBOL(pci_add_resource_offset);
35 void pci_add_resource(struct list_head *resources, struct resource *res)
37 pci_add_resource_offset(resources, res, 0);
39 EXPORT_SYMBOL(pci_add_resource);
41 void pci_free_resource_list(struct list_head *resources)
43 resource_list_free(resources);
45 EXPORT_SYMBOL(pci_free_resource_list);
47 void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,
50 struct pci_bus_resource *bus_res;
52 bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
54 dev_err(&bus->dev, "can't add %pR resource\n", res);
59 bus_res->flags = flags;
60 list_add_tail(&bus_res->list, &bus->resources);
63 struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n)
65 struct pci_bus_resource *bus_res;
67 if (n < PCI_BRIDGE_RESOURCE_NUM)
68 return bus->resource[n];
70 n -= PCI_BRIDGE_RESOURCE_NUM;
71 list_for_each_entry(bus_res, &bus->resources, list) {
77 EXPORT_SYMBOL_GPL(pci_bus_resource_n);
79 void pci_bus_remove_resource(struct pci_bus *bus, struct resource *res)
81 struct pci_bus_resource *bus_res, *tmp;
84 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
85 if (bus->resource[i] == res) {
86 bus->resource[i] = NULL;
91 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
92 if (bus_res->res == res) {
93 list_del(&bus_res->list);
100 void pci_bus_remove_resources(struct pci_bus *bus)
103 struct pci_bus_resource *bus_res, *tmp;
105 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
106 bus->resource[i] = NULL;
108 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
109 list_del(&bus_res->list);
114 int devm_request_pci_bus_resources(struct device *dev,
115 struct list_head *resources)
117 struct resource_entry *win;
118 struct resource *parent, *res;
121 resource_list_for_each_entry(win, resources) {
123 switch (resource_type(res)) {
125 parent = &ioport_resource;
128 parent = &iomem_resource;
134 err = devm_request_resource(dev, parent, res);
141 EXPORT_SYMBOL_GPL(devm_request_pci_bus_resources);
143 static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
144 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
145 static struct pci_bus_region pci_64_bit = {0,
146 (pci_bus_addr_t) 0xffffffffffffffffULL};
147 static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL,
148 (pci_bus_addr_t) 0xffffffffffffffffULL};
152 * @res contains CPU addresses. Clip it so the corresponding bus addresses
153 * on @bus are entirely within @region. This is used to control the bus
154 * addresses of resources we allocate, e.g., we may need a resource that
155 * can be mapped by a 32-bit BAR.
157 static void pci_clip_resource_to_region(struct pci_bus *bus,
158 struct resource *res,
159 struct pci_bus_region *region)
161 struct pci_bus_region r;
163 pcibios_resource_to_bus(bus, &r, res);
164 if (r.start < region->start)
165 r.start = region->start;
166 if (r.end > region->end)
170 res->end = res->start - 1;
172 pcibios_bus_to_resource(bus, res, &r);
175 static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,
176 resource_size_t size, resource_size_t align,
177 resource_size_t min, unsigned long type_mask,
178 resource_size_t (*alignf)(void *,
179 const struct resource *,
183 struct pci_bus_region *region)
186 struct resource *r, avail;
189 type_mask |= IORESOURCE_TYPE_BITS;
191 pci_bus_for_each_resource(bus, r, i) {
192 resource_size_t min_used = min;
197 /* type_mask must match */
198 if ((res->flags ^ r->flags) & type_mask)
201 /* We cannot allocate a non-prefetching resource
202 from a pre-fetching area */
203 if ((r->flags & IORESOURCE_PREFETCH) &&
204 !(res->flags & IORESOURCE_PREFETCH))
208 pci_clip_resource_to_region(bus, &avail, region);
211 * "min" is typically PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM to
212 * protect badly documented motherboard resources, but if
213 * this is an already-configured bridge window, its start
217 min_used = avail.start;
221 /* Ok, try it out.. */
222 ret = allocate_resource(r, res, size, min_used, max,
223 align, alignf, alignf_data);
231 * pci_bus_alloc_resource - allocate a resource from a parent bus
233 * @res: resource to allocate
234 * @size: size of resource to allocate
235 * @align: alignment of resource to allocate
236 * @min: minimum /proc/iomem address to allocate
237 * @type_mask: IORESOURCE_* type flags
238 * @alignf: resource alignment function
239 * @alignf_data: data argument for resource alignment function
241 * Given the PCI bus a device resides on, the size, minimum address,
242 * alignment and type, try to find an acceptable resource allocation
243 * for a specific device resource.
245 int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
246 resource_size_t size, resource_size_t align,
247 resource_size_t min, unsigned long type_mask,
248 resource_size_t (*alignf)(void *,
249 const struct resource *,
254 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
257 if (res->flags & IORESOURCE_MEM_64) {
258 rc = pci_bus_alloc_from_region(bus, res, size, align, min,
259 type_mask, alignf, alignf_data,
264 return pci_bus_alloc_from_region(bus, res, size, align, min,
265 type_mask, alignf, alignf_data,
270 return pci_bus_alloc_from_region(bus, res, size, align, min,
271 type_mask, alignf, alignf_data,
274 EXPORT_SYMBOL(pci_bus_alloc_resource);
277 * The @idx resource of @dev should be a PCI-PCI bridge window. If this
278 * resource fits inside a window of an upstream bridge, do nothing. If it
279 * overlaps an upstream window but extends outside it, clip the resource so
280 * it fits completely inside.
282 bool pci_bus_clip_resource(struct pci_dev *dev, int idx)
284 struct pci_bus *bus = dev->bus;
285 struct resource *res = &dev->resource[idx];
286 struct resource orig_res = *res;
290 pci_bus_for_each_resource(bus, r, i) {
291 resource_size_t start, end;
296 if (resource_type(res) != resource_type(r))
299 start = max(r->start, res->start);
300 end = min(r->end, res->end);
303 continue; /* no overlap */
305 if (res->start == start && res->end == end)
306 return false; /* no change */
310 res->flags &= ~IORESOURCE_UNSET;
311 orig_res.flags &= ~IORESOURCE_UNSET;
312 pci_info(dev, "%pR clipped to %pR\n", &orig_res, res);
320 void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
322 void __weak pcibios_bus_add_device(struct pci_dev *pdev) { }
325 * pci_bus_add_device - start driver for a single device
326 * @dev: device to add
328 * This adds add sysfs entries and start device drivers
330 void pci_bus_add_device(struct pci_dev *dev)
335 * Can not put in pci_device_add yet because resources
336 * are not assigned yet for some devices.
338 pcibios_bus_add_device(dev);
339 pci_fixup_device(pci_fixup_final, dev);
340 pci_create_sysfs_dev_files(dev);
341 pci_proc_attach_device(dev);
342 pci_bridge_d3_update(dev);
344 dev->match_driver = true;
345 retval = device_attach(&dev->dev);
346 if (retval < 0 && retval != -EPROBE_DEFER)
347 pci_warn(dev, "device attach failed (%d)\n", retval);
349 pci_dev_assign_added(dev, true);
351 EXPORT_SYMBOL_GPL(pci_bus_add_device);
354 * pci_bus_add_devices - start driver for PCI devices
355 * @bus: bus to check for new devices
357 * Start driver for PCI devices and add some sysfs entries.
359 void pci_bus_add_devices(const struct pci_bus *bus)
362 struct pci_bus *child;
364 list_for_each_entry(dev, &bus->devices, bus_list) {
365 /* Skip already-added devices */
366 if (pci_dev_is_added(dev))
368 pci_bus_add_device(dev);
371 list_for_each_entry(dev, &bus->devices, bus_list) {
372 /* Skip if device attach failed */
373 if (!pci_dev_is_added(dev))
375 child = dev->subordinate;
377 pci_bus_add_devices(child);
380 EXPORT_SYMBOL(pci_bus_add_devices);
382 /** pci_walk_bus - walk devices on/under bus, calling callback.
383 * @top bus whose devices should be walked
384 * @cb callback to be called for each device found
385 * @userdata arbitrary pointer to be passed to callback.
387 * Walk the given bus, including any bridged devices
388 * on buses under this bus. Call the provided callback
389 * on each device found.
391 * We check the return of @cb each time. If it returns anything
392 * other than 0, we break out.
395 void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
400 struct list_head *next;
404 down_read(&pci_bus_sem);
405 next = top->devices.next;
407 if (next == &bus->devices) {
408 /* end of this bus, go up or finish */
411 next = bus->self->bus_list.next;
412 bus = bus->self->bus;
415 dev = list_entry(next, struct pci_dev, bus_list);
416 if (dev->subordinate) {
417 /* this is a pci-pci bridge, do its devices next */
418 next = dev->subordinate->devices.next;
419 bus = dev->subordinate;
421 next = dev->bus_list.next;
423 retval = cb(dev, userdata);
427 up_read(&pci_bus_sem);
429 EXPORT_SYMBOL_GPL(pci_walk_bus);
431 struct pci_bus *pci_bus_get(struct pci_bus *bus)
434 get_device(&bus->dev);
438 void pci_bus_put(struct pci_bus *bus)
441 put_device(&bus->dev);