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