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 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 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 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 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 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 79 void pci_bus_remove_resource(struct pci_bus *bus, struct resource *res) 80 { 81 struct pci_bus_resource *bus_res, *tmp; 82 int i; 83 84 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) { 85 if (bus->resource[i] == res) { 86 bus->resource[i] = NULL; 87 return; 88 } 89 } 90 91 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) { 92 if (bus_res->res == res) { 93 list_del(&bus_res->list); 94 kfree(bus_res); 95 return; 96 } 97 } 98 } 99 100 void pci_bus_remove_resources(struct pci_bus *bus) 101 { 102 int i; 103 struct pci_bus_resource *bus_res, *tmp; 104 105 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) 106 bus->resource[i] = NULL; 107 108 list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) { 109 list_del(&bus_res->list); 110 kfree(bus_res); 111 } 112 } 113 114 int devm_request_pci_bus_resources(struct device *dev, 115 struct list_head *resources) 116 { 117 struct resource_entry *win; 118 struct resource *parent, *res; 119 int err; 120 121 resource_list_for_each_entry(win, resources) { 122 res = win->res; 123 switch (resource_type(res)) { 124 case IORESOURCE_IO: 125 parent = &ioport_resource; 126 break; 127 case IORESOURCE_MEM: 128 parent = &iomem_resource; 129 break; 130 default: 131 continue; 132 } 133 134 err = devm_request_resource(dev, parent, res); 135 if (err) 136 return err; 137 } 138 139 return 0; 140 } 141 EXPORT_SYMBOL_GPL(devm_request_pci_bus_resources); 142 143 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}; 149 #endif 150 151 /* 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. 156 */ 157 static void pci_clip_resource_to_region(struct pci_bus *bus, 158 struct resource *res, 159 struct pci_bus_region *region) 160 { 161 struct pci_bus_region r; 162 163 pcibios_resource_to_bus(bus, &r, res); 164 if (r.start < region->start) 165 r.start = region->start; 166 if (r.end > region->end) 167 r.end = region->end; 168 169 if (r.end < r.start) 170 res->end = res->start - 1; 171 else 172 pcibios_bus_to_resource(bus, res, &r); 173 } 174 175 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 *, 180 resource_size_t, 181 resource_size_t), 182 void *alignf_data, 183 struct pci_bus_region *region) 184 { 185 int i, ret; 186 struct resource *r, avail; 187 resource_size_t max; 188 189 type_mask |= IORESOURCE_TYPE_BITS; 190 191 pci_bus_for_each_resource(bus, r, i) { 192 resource_size_t min_used = min; 193 194 if (!r) 195 continue; 196 197 /* type_mask must match */ 198 if ((res->flags ^ r->flags) & type_mask) 199 continue; 200 201 /* We cannot allocate a non-prefetching resource 202 from a pre-fetching area */ 203 if ((r->flags & IORESOURCE_PREFETCH) && 204 !(res->flags & IORESOURCE_PREFETCH)) 205 continue; 206 207 avail = *r; 208 pci_clip_resource_to_region(bus, &avail, region); 209 210 /* 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 214 * overrides "min". 215 */ 216 if (avail.start) 217 min_used = avail.start; 218 219 max = avail.end; 220 221 /* Don't bother if available space isn't large enough */ 222 if (size > max - min_used + 1) 223 continue; 224 225 /* Ok, try it out.. */ 226 ret = allocate_resource(r, res, size, min_used, max, 227 align, alignf, alignf_data); 228 if (ret == 0) 229 return 0; 230 } 231 return -ENOMEM; 232 } 233 234 /** 235 * pci_bus_alloc_resource - allocate a resource from a parent bus 236 * @bus: PCI bus 237 * @res: resource to allocate 238 * @size: size of resource to allocate 239 * @align: alignment of resource to allocate 240 * @min: minimum /proc/iomem address to allocate 241 * @type_mask: IORESOURCE_* type flags 242 * @alignf: resource alignment function 243 * @alignf_data: data argument for resource alignment function 244 * 245 * Given the PCI bus a device resides on, the size, minimum address, 246 * alignment and type, try to find an acceptable resource allocation 247 * for a specific device resource. 248 */ 249 int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res, 250 resource_size_t size, resource_size_t align, 251 resource_size_t min, unsigned long type_mask, 252 resource_size_t (*alignf)(void *, 253 const struct resource *, 254 resource_size_t, 255 resource_size_t), 256 void *alignf_data) 257 { 258 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT 259 int rc; 260 261 if (res->flags & IORESOURCE_MEM_64) { 262 rc = pci_bus_alloc_from_region(bus, res, size, align, min, 263 type_mask, alignf, alignf_data, 264 &pci_high); 265 if (rc == 0) 266 return 0; 267 268 return pci_bus_alloc_from_region(bus, res, size, align, min, 269 type_mask, alignf, alignf_data, 270 &pci_64_bit); 271 } 272 #endif 273 274 return pci_bus_alloc_from_region(bus, res, size, align, min, 275 type_mask, alignf, alignf_data, 276 &pci_32_bit); 277 } 278 EXPORT_SYMBOL(pci_bus_alloc_resource); 279 280 /* 281 * The @idx resource of @dev should be a PCI-PCI bridge window. If this 282 * resource fits inside a window of an upstream bridge, do nothing. If it 283 * overlaps an upstream window but extends outside it, clip the resource so 284 * it fits completely inside. 285 */ 286 bool pci_bus_clip_resource(struct pci_dev *dev, int idx) 287 { 288 struct pci_bus *bus = dev->bus; 289 struct resource *res = &dev->resource[idx]; 290 struct resource orig_res = *res; 291 struct resource *r; 292 int i; 293 294 pci_bus_for_each_resource(bus, r, i) { 295 resource_size_t start, end; 296 297 if (!r) 298 continue; 299 300 if (resource_type(res) != resource_type(r)) 301 continue; 302 303 start = max(r->start, res->start); 304 end = min(r->end, res->end); 305 306 if (start > end) 307 continue; /* no overlap */ 308 309 if (res->start == start && res->end == end) 310 return false; /* no change */ 311 312 res->start = start; 313 res->end = end; 314 res->flags &= ~IORESOURCE_UNSET; 315 orig_res.flags &= ~IORESOURCE_UNSET; 316 pci_info(dev, "%pR clipped to %pR\n", &orig_res, res); 317 318 return true; 319 } 320 321 return false; 322 } 323 324 void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { } 325 326 void __weak pcibios_bus_add_device(struct pci_dev *pdev) { } 327 328 /** 329 * pci_bus_add_device - start driver for a single device 330 * @dev: device to add 331 * 332 * This adds add sysfs entries and start device drivers 333 */ 334 void pci_bus_add_device(struct pci_dev *dev) 335 { 336 int retval; 337 338 /* 339 * Can not put in pci_device_add yet because resources 340 * are not assigned yet for some devices. 341 */ 342 pcibios_bus_add_device(dev); 343 pci_fixup_device(pci_fixup_final, dev); 344 pci_create_sysfs_dev_files(dev); 345 pci_proc_attach_device(dev); 346 pci_bridge_d3_update(dev); 347 348 dev->match_driver = true; 349 retval = device_attach(&dev->dev); 350 if (retval < 0 && retval != -EPROBE_DEFER) 351 pci_warn(dev, "device attach failed (%d)\n", retval); 352 353 pci_dev_assign_added(dev, true); 354 } 355 EXPORT_SYMBOL_GPL(pci_bus_add_device); 356 357 /** 358 * pci_bus_add_devices - start driver for PCI devices 359 * @bus: bus to check for new devices 360 * 361 * Start driver for PCI devices and add some sysfs entries. 362 */ 363 void pci_bus_add_devices(const struct pci_bus *bus) 364 { 365 struct pci_dev *dev; 366 struct pci_bus *child; 367 368 list_for_each_entry(dev, &bus->devices, bus_list) { 369 /* Skip already-added devices */ 370 if (pci_dev_is_added(dev)) 371 continue; 372 pci_bus_add_device(dev); 373 } 374 375 list_for_each_entry(dev, &bus->devices, bus_list) { 376 /* Skip if device attach failed */ 377 if (!pci_dev_is_added(dev)) 378 continue; 379 child = dev->subordinate; 380 if (child) 381 pci_bus_add_devices(child); 382 } 383 } 384 EXPORT_SYMBOL(pci_bus_add_devices); 385 386 /** pci_walk_bus - walk devices on/under bus, calling callback. 387 * @top bus whose devices should be walked 388 * @cb callback to be called for each device found 389 * @userdata arbitrary pointer to be passed to callback. 390 * 391 * Walk the given bus, including any bridged devices 392 * on buses under this bus. Call the provided callback 393 * on each device found. 394 * 395 * We check the return of @cb each time. If it returns anything 396 * other than 0, we break out. 397 * 398 */ 399 void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), 400 void *userdata) 401 { 402 struct pci_dev *dev; 403 struct pci_bus *bus; 404 struct list_head *next; 405 int retval; 406 407 bus = top; 408 down_read(&pci_bus_sem); 409 next = top->devices.next; 410 for (;;) { 411 if (next == &bus->devices) { 412 /* end of this bus, go up or finish */ 413 if (bus == top) 414 break; 415 next = bus->self->bus_list.next; 416 bus = bus->self->bus; 417 continue; 418 } 419 dev = list_entry(next, struct pci_dev, bus_list); 420 if (dev->subordinate) { 421 /* this is a pci-pci bridge, do its devices next */ 422 next = dev->subordinate->devices.next; 423 bus = dev->subordinate; 424 } else 425 next = dev->bus_list.next; 426 427 retval = cb(dev, userdata); 428 if (retval) 429 break; 430 } 431 up_read(&pci_bus_sem); 432 } 433 EXPORT_SYMBOL_GPL(pci_walk_bus); 434 435 struct pci_bus *pci_bus_get(struct pci_bus *bus) 436 { 437 if (bus) 438 get_device(&bus->dev); 439 return bus; 440 } 441 442 void pci_bus_put(struct pci_bus *bus) 443 { 444 if (bus) 445 put_device(&bus->dev); 446 } 447