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1// SPDX-License-Identifier: GPL-2.02/*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/proc_fs.h>17#include <linux/slab.h>18 19#include "pci.h"20 21void pci_add_resource_offset(struct list_head *resources, struct resource *res,22 resource_size_t offset)23{24 struct resource_entry *entry;25 26 entry = resource_list_create_entry(res, 0);27 if (!entry) {28 pr_err("PCI: can't add host bridge window %pR\n", res);29 return;30 }31 32 entry->offset = offset;33 resource_list_add_tail(entry, resources);34}35EXPORT_SYMBOL(pci_add_resource_offset);36 37void pci_add_resource(struct list_head *resources, struct resource *res)38{39 pci_add_resource_offset(resources, res, 0);40}41EXPORT_SYMBOL(pci_add_resource);42 43void pci_free_resource_list(struct list_head *resources)44{45 resource_list_free(resources);46}47EXPORT_SYMBOL(pci_free_resource_list);48 49void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,50 unsigned int flags)51{52 struct pci_bus_resource *bus_res;53 54 bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);55 if (!bus_res) {56 dev_err(&bus->dev, "can't add %pR resource\n", res);57 return;58 }59 60 bus_res->res = res;61 bus_res->flags = flags;62 list_add_tail(&bus_res->list, &bus->resources);63}64 65struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n)66{67 struct pci_bus_resource *bus_res;68 69 if (n < PCI_BRIDGE_RESOURCE_NUM)70 return bus->resource[n];71 72 n -= PCI_BRIDGE_RESOURCE_NUM;73 list_for_each_entry(bus_res, &bus->resources, list) {74 if (n-- == 0)75 return bus_res->res;76 }77 return NULL;78}79EXPORT_SYMBOL_GPL(pci_bus_resource_n);80 81void pci_bus_remove_resource(struct pci_bus *bus, struct resource *res)82{83 struct pci_bus_resource *bus_res, *tmp;84 int i;85 86 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {87 if (bus->resource[i] == res) {88 bus->resource[i] = NULL;89 return;90 }91 }92 93 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {94 if (bus_res->res == res) {95 list_del(&bus_res->list);96 kfree(bus_res);97 return;98 }99 }100}101 102void pci_bus_remove_resources(struct pci_bus *bus)103{104 int i;105 struct pci_bus_resource *bus_res, *tmp;106 107 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)108 bus->resource[i] = NULL;109 110 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {111 list_del(&bus_res->list);112 kfree(bus_res);113 }114}115 116int devm_request_pci_bus_resources(struct device *dev,117 struct list_head *resources)118{119 struct resource_entry *win;120 struct resource *parent, *res;121 int err;122 123 resource_list_for_each_entry(win, resources) {124 res = win->res;125 switch (resource_type(res)) {126 case IORESOURCE_IO:127 parent = &ioport_resource;128 break;129 case IORESOURCE_MEM:130 parent = &iomem_resource;131 break;132 default:133 continue;134 }135 136 err = devm_request_resource(dev, parent, res);137 if (err)138 return err;139 }140 141 return 0;142}143EXPORT_SYMBOL_GPL(devm_request_pci_bus_resources);144 145static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};146#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT147static struct pci_bus_region pci_64_bit = {0,148 (pci_bus_addr_t) 0xffffffffffffffffULL};149static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL,150 (pci_bus_addr_t) 0xffffffffffffffffULL};151#endif152 153/*154 * @res contains CPU addresses. Clip it so the corresponding bus addresses155 * on @bus are entirely within @region. This is used to control the bus156 * addresses of resources we allocate, e.g., we may need a resource that157 * can be mapped by a 32-bit BAR.158 */159static void pci_clip_resource_to_region(struct pci_bus *bus,160 struct resource *res,161 struct pci_bus_region *region)162{163 struct pci_bus_region r;164 165 pcibios_resource_to_bus(bus, &r, res);166 if (r.start < region->start)167 r.start = region->start;168 if (r.end > region->end)169 r.end = region->end;170 171 if (r.end < r.start)172 res->end = res->start - 1;173 else174 pcibios_bus_to_resource(bus, res, &r);175}176 177static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,178 resource_size_t size, resource_size_t align,179 resource_size_t min, unsigned long type_mask,180 resource_alignf alignf,181 void *alignf_data,182 struct pci_bus_region *region)183{184 struct resource *r, avail;185 resource_size_t max;186 int ret;187 188 type_mask |= IORESOURCE_TYPE_BITS;189 190 pci_bus_for_each_resource(bus, r) {191 resource_size_t min_used = min;192 193 if (!r)194 continue;195 196 /* type_mask must match */197 if ((res->flags ^ r->flags) & type_mask)198 continue;199 200 /* We cannot allocate a non-prefetching resource201 from a pre-fetching area */202 if ((r->flags & IORESOURCE_PREFETCH) &&203 !(res->flags & IORESOURCE_PREFETCH))204 continue;205 206 avail = *r;207 pci_clip_resource_to_region(bus, &avail, region);208 209 /*210 * "min" is typically PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM to211 * protect badly documented motherboard resources, but if212 * this is an already-configured bridge window, its start213 * overrides "min".214 */215 if (avail.start)216 min_used = avail.start;217 218 max = avail.end;219 220 /* Don't bother if available space isn't large enough */221 if (size > max - min_used + 1)222 continue;223 224 /* Ok, try it out.. */225 ret = allocate_resource(r, res, size, min_used, max,226 align, alignf, alignf_data);227 if (ret == 0)228 return 0;229 }230 return -ENOMEM;231}232 233/**234 * pci_bus_alloc_resource - allocate a resource from a parent bus235 * @bus: PCI bus236 * @res: resource to allocate237 * @size: size of resource to allocate238 * @align: alignment of resource to allocate239 * @min: minimum /proc/iomem address to allocate240 * @type_mask: IORESOURCE_* type flags241 * @alignf: resource alignment function242 * @alignf_data: data argument for resource alignment function243 *244 * Given the PCI bus a device resides on, the size, minimum address,245 * alignment and type, try to find an acceptable resource allocation246 * for a specific device resource.247 */248int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,249 resource_size_t size, resource_size_t align,250 resource_size_t min, unsigned long type_mask,251 resource_alignf alignf,252 void *alignf_data)253{254#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT255 int rc;256 257 if (res->flags & IORESOURCE_MEM_64) {258 rc = pci_bus_alloc_from_region(bus, res, size, align, min,259 type_mask, alignf, alignf_data,260 &pci_high);261 if (rc == 0)262 return 0;263 264 return pci_bus_alloc_from_region(bus, res, size, align, min,265 type_mask, alignf, alignf_data,266 &pci_64_bit);267 }268#endif269 270 return pci_bus_alloc_from_region(bus, res, size, align, min,271 type_mask, alignf, alignf_data,272 &pci_32_bit);273}274EXPORT_SYMBOL(pci_bus_alloc_resource);275 276/*277 * The @idx resource of @dev should be a PCI-PCI bridge window. If this278 * resource fits inside a window of an upstream bridge, do nothing. If it279 * overlaps an upstream window but extends outside it, clip the resource so280 * it fits completely inside.281 */282bool pci_bus_clip_resource(struct pci_dev *dev, int idx)283{284 struct pci_bus *bus = dev->bus;285 struct resource *res = &dev->resource[idx];286 struct resource orig_res = *res;287 struct resource *r;288 289 pci_bus_for_each_resource(bus, r) {290 resource_size_t start, end;291 292 if (!r)293 continue;294 295 if (resource_type(res) != resource_type(r))296 continue;297 298 start = max(r->start, res->start);299 end = min(r->end, res->end);300 301 if (start > end)302 continue; /* no overlap */303 304 if (res->start == start && res->end == end)305 return false; /* no change */306 307 res->start = start;308 res->end = end;309 res->flags &= ~IORESOURCE_UNSET;310 orig_res.flags &= ~IORESOURCE_UNSET;311 pci_info(dev, "%pR clipped to %pR\n", &orig_res, res);312 313 return true;314 }315 316 return false;317}318 319void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }320 321void __weak pcibios_bus_add_device(struct pci_dev *pdev) { }322 323/**324 * pci_bus_add_device - start driver for a single device325 * @dev: device to add326 *327 * This adds add sysfs entries and start device drivers328 */329void pci_bus_add_device(struct pci_dev *dev)330{331 struct device_node *dn = dev->dev.of_node;332 int retval;333 334 /*335 * Can not put in pci_device_add yet because resources336 * are not assigned yet for some devices.337 */338 pcibios_bus_add_device(dev);339 pci_fixup_device(pci_fixup_final, dev);340 if (pci_is_bridge(dev))341 of_pci_make_dev_node(dev);342 pci_create_sysfs_dev_files(dev);343 pci_proc_attach_device(dev);344 pci_bridge_d3_update(dev);345 346 dev->match_driver = !dn || of_device_is_available(dn);347 retval = device_attach(&dev->dev);348 if (retval < 0 && retval != -EPROBE_DEFER)349 pci_warn(dev, "device attach failed (%d)\n", retval);350 351 pci_dev_assign_added(dev, true);352 353 if (dev_of_node(&dev->dev) && pci_is_bridge(dev)) {354 retval = of_platform_populate(dev_of_node(&dev->dev), NULL, NULL,355 &dev->dev);356 if (retval)357 pci_err(dev, "failed to populate child OF nodes (%d)\n",358 retval);359 }360}361EXPORT_SYMBOL_GPL(pci_bus_add_device);362 363/**364 * pci_bus_add_devices - start driver for PCI devices365 * @bus: bus to check for new devices366 *367 * Start driver for PCI devices and add some sysfs entries.368 */369void pci_bus_add_devices(const struct pci_bus *bus)370{371 struct pci_dev *dev;372 struct pci_bus *child;373 374 list_for_each_entry(dev, &bus->devices, bus_list) {375 /* Skip already-added devices */376 if (pci_dev_is_added(dev))377 continue;378 pci_bus_add_device(dev);379 }380 381 list_for_each_entry(dev, &bus->devices, bus_list) {382 /* Skip if device attach failed */383 if (!pci_dev_is_added(dev))384 continue;385 child = dev->subordinate;386 if (child)387 pci_bus_add_devices(child);388 }389}390EXPORT_SYMBOL(pci_bus_add_devices);391 392static void __pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),393 void *userdata, bool locked)394{395 struct pci_dev *dev;396 struct pci_bus *bus;397 struct list_head *next;398 int retval;399 400 bus = top;401 if (!locked)402 down_read(&pci_bus_sem);403 next = top->devices.next;404 for (;;) {405 if (next == &bus->devices) {406 /* end of this bus, go up or finish */407 if (bus == top)408 break;409 next = bus->self->bus_list.next;410 bus = bus->self->bus;411 continue;412 }413 dev = list_entry(next, struct pci_dev, bus_list);414 if (dev->subordinate) {415 /* this is a pci-pci bridge, do its devices next */416 next = dev->subordinate->devices.next;417 bus = dev->subordinate;418 } else419 next = dev->bus_list.next;420 421 retval = cb(dev, userdata);422 if (retval)423 break;424 }425 if (!locked)426 up_read(&pci_bus_sem);427}428 429/**430 * pci_walk_bus - walk devices on/under bus, calling callback.431 * @top: bus whose devices should be walked432 * @cb: callback to be called for each device found433 * @userdata: arbitrary pointer to be passed to callback434 *435 * Walk the given bus, including any bridged devices436 * on buses under this bus. Call the provided callback437 * on each device found.438 *439 * We check the return of @cb each time. If it returns anything440 * other than 0, we break out.441 */442void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata)443{444 __pci_walk_bus(top, cb, userdata, false);445}446EXPORT_SYMBOL_GPL(pci_walk_bus);447 448void pci_walk_bus_locked(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata)449{450 lockdep_assert_held(&pci_bus_sem);451 452 __pci_walk_bus(top, cb, userdata, true);453}454EXPORT_SYMBOL_GPL(pci_walk_bus_locked);455 456struct pci_bus *pci_bus_get(struct pci_bus *bus)457{458 if (bus)459 get_device(&bus->dev);460 return bus;461}462 463void pci_bus_put(struct pci_bus *bus)464{465 if (bus)466 put_device(&bus->dev);467}468