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/proc_fs.h> 17 #include <linux/slab.h> 18 19 #include "pci.h" 20 21 void 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 } 35 EXPORT_SYMBOL(pci_add_resource_offset); 36 37 void pci_add_resource(struct list_head *resources, struct resource *res) 38 { 39 pci_add_resource_offset(resources, res, 0); 40 } 41 EXPORT_SYMBOL(pci_add_resource); 42 43 void pci_free_resource_list(struct list_head *resources) 44 { 45 resource_list_free(resources); 46 } 47 EXPORT_SYMBOL(pci_free_resource_list); 48 49 void 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 65 struct 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 } 79 EXPORT_SYMBOL_GPL(pci_bus_resource_n); 80 81 void 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 } 101 102 void 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 } 115 116 int 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 } 143 EXPORT_SYMBOL_GPL(devm_request_pci_bus_resources); 144 145 static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL}; 146 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT 147 static struct pci_bus_region pci_64_bit = {0, 148 (pci_bus_addr_t) 0xffffffffffffffffULL}; 149 static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL, 150 (pci_bus_addr_t) 0xffffffffffffffffULL}; 151 #endif 152 153 /* 154 * @res contains CPU addresses. Clip it so the corresponding bus addresses 155 * on @bus are entirely within @region. This is used to control the bus 156 * addresses of resources we allocate, e.g., we may need a resource that 157 * can be mapped by a 32-bit BAR. 158 */ 159 static 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 else 174 pcibios_bus_to_resource(bus, res, &r); 175 } 176 177 static 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 resource 201 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 to 211 * protect badly documented motherboard resources, but if 212 * this is an already-configured bridge window, its start 213 * 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 bus 235 * @bus: PCI bus 236 * @res: resource to allocate 237 * @size: size of resource to allocate 238 * @align: alignment of resource to allocate 239 * @min: minimum /proc/iomem address to allocate 240 * @type_mask: IORESOURCE_* type flags 241 * @alignf: resource alignment function 242 * @alignf_data: data argument for resource alignment function 243 * 244 * Given the PCI bus a device resides on, the size, minimum address, 245 * alignment and type, try to find an acceptable resource allocation 246 * for a specific device resource. 247 */ 248 int 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_64BIT 255 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 #endif 269 270 return pci_bus_alloc_from_region(bus, res, size, align, min, 271 type_mask, alignf, alignf_data, 272 &pci_32_bit); 273 } 274 EXPORT_SYMBOL(pci_bus_alloc_resource); 275 276 /* 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. 281 */ 282 bool 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 } 318 319 void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { } 320 321 void __weak pcibios_bus_add_device(struct pci_dev *pdev) { } 322 323 /** 324 * pci_bus_add_device - start driver for a single device 325 * @dev: device to add 326 * 327 * This adds add sysfs entries and start device drivers 328 */ 329 void 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 resources 336 * 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 } 361 EXPORT_SYMBOL_GPL(pci_bus_add_device); 362 363 /** 364 * pci_bus_add_devices - start driver for PCI devices 365 * @bus: bus to check for new devices 366 * 367 * Start driver for PCI devices and add some sysfs entries. 368 */ 369 void 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 } 390 EXPORT_SYMBOL(pci_bus_add_devices); 391 392 static 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 } else 419 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 walked 432 * @cb: callback to be called for each device found 433 * @userdata: arbitrary pointer to be passed to callback 434 * 435 * Walk the given bus, including any bridged devices 436 * on buses under this bus. Call the provided callback 437 * on each device found. 438 * 439 * We check the return of @cb each time. If it returns anything 440 * other than 0, we break out. 441 */ 442 void 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 } 446 EXPORT_SYMBOL_GPL(pci_walk_bus); 447 448 void 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 } 454 EXPORT_SYMBOL_GPL(pci_walk_bus_locked); 455 456 struct pci_bus *pci_bus_get(struct pci_bus *bus) 457 { 458 if (bus) 459 get_device(&bus->dev); 460 return bus; 461 } 462 463 void pci_bus_put(struct pci_bus *bus) 464 { 465 if (bus) 466 put_device(&bus->dev); 467 } 468