drivers/of/address.c

   1
   2 #define pr_fmt(fmt)     "OF: " fmt
   3
   4 #include <linux/device.h>
   5 #include <linux/io.h>
   6 #include <linux/ioport.h>
   7 #include <linux/module.h>
   8 #include <linux/of_address.h>
   9 #include <linux/pci.h>
  10 #include <linux/pci_regs.h>
  11 #include <linux/sizes.h>
  12 #include <linux/slab.h>
  13 #include <linux/string.h>
  14
  15 /* Max address size we deal with */
  16 #define OF_MAX_ADDR_CELLS       4
  17 #define OF_CHECK_ADDR_COUNT(na) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
  18 #define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
  19
  20 static struct of_bus *of_match_bus(struct device_node *np);
  21 static int __of_address_to_resource(struct device_node *dev,
  22                 const __be32 *addrp, u64 size, unsigned int flags,
  23                 const char *name, struct resource *r);
  24
  25 /* Debug utility */
  26 #ifdef DEBUG
  27 static void of_dump_addr(const char *s, const __be32 *addr, int na)
  28 {
  29         pr_debug("%s", s);
  30         while (na--)
  31                 pr_cont(" %08x", be32_to_cpu(*(addr++)));
  32         pr_cont("\n");
  33 }
  34 #else
  35 static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
  36 #endif
  37
  38 /* Callbacks for bus specific translators */
  39 struct of_bus {
  40         const char      *name;
  41         const char      *addresses;
  42         int             (*match)(struct device_node *parent);
  43         void            (*count_cells)(struct device_node *child,
  44                                        int *addrc, int *sizec);
  45         u64             (*map)(__be32 *addr, const __be32 *range,
  46                                 int na, int ns, int pna);
  47         int             (*translate)(__be32 *addr, u64 offset, int na);
  48         unsigned int    (*get_flags)(const __be32 *addr);
  49 };
  50
  51 /*
  52  * Default translator (generic bus)
  53  */
  54
  55 static void of_bus_default_count_cells(struct device_node *dev,
  56                                        int *addrc, int *sizec)
  57 {
  58         if (addrc)
  59                 *addrc = of_n_addr_cells(dev);
  60         if (sizec)
  61                 *sizec = of_n_size_cells(dev);
  62 }
  63
  64 static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
  65                 int na, int ns, int pna)
  66 {
  67         u64 cp, s, da;
  68
  69         cp = of_read_number(range, na);
  70         s  = of_read_number(range + na + pna, ns);
  71         da = of_read_number(addr, na);
  72
  73         pr_debug("default map, cp=%llx, s=%llx, da=%llx\n",
  74                  (unsigned long long)cp, (unsigned long long)s,
  75                  (unsigned long long)da);
  76
  77         if (da < cp || da >= (cp + s))
  78                 return OF_BAD_ADDR;
  79         return da - cp;
  80 }
  81
  82 static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
  83 {
  84         u64 a = of_read_number(addr, na);
  85         memset(addr, 0, na * 4);
  86         a += offset;
  87         if (na > 1)
  88                 addr[na - 2] = cpu_to_be32(a >> 32);
  89         addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
  90
  91         return 0;
  92 }
  93
  94 static unsigned int of_bus_default_get_flags(const __be32 *addr)
  95 {
  96         return IORESOURCE_MEM;
  97 }
  98
  99 #ifdef CONFIG_OF_ADDRESS_PCI
 100 /*
 101  * PCI bus specific translator
 102  */
 103
 104 static int of_bus_pci_match(struct device_node *np)
 105 {
 106         /*
 107          * "pciex" is PCI Express
 108          * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
 109          * "ht" is hypertransport
 110          */
 111         return !strcmp(np->type, "pci") || !strcmp(np->type, "pciex") ||
 112                 !strcmp(np->type, "vci") || !strcmp(np->type, "ht");
 113 }
 114
 115 static void of_bus_pci_count_cells(struct device_node *np,
 116                                    int *addrc, int *sizec)
 117 {
 118         if (addrc)
 119                 *addrc = 3;
 120         if (sizec)
 121                 *sizec = 2;
 122 }
 123
 124 static unsigned int of_bus_pci_get_flags(const __be32 *addr)
 125 {
 126         unsigned int flags = 0;
 127         u32 w = be32_to_cpup(addr);
 128
 129         switch((w >> 24) & 0x03) {
 130         case 0x01:
 131                 flags |= IORESOURCE_IO;
 132                 break;
 133         case 0x02: /* 32 bits */
 134         case 0x03: /* 64 bits */
 135                 flags |= IORESOURCE_MEM;
 136                 break;
 137         }
 138         if (w & 0x40000000)
 139                 flags |= IORESOURCE_PREFETCH;
 140         return flags;
 141 }
 142
 143 static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
 144                 int pna)
 145 {
 146         u64 cp, s, da;
 147         unsigned int af, rf;
 148
 149         af = of_bus_pci_get_flags(addr);
 150         rf = of_bus_pci_get_flags(range);
 151
 152         /* Check address type match */
 153         if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
 154                 return OF_BAD_ADDR;
 155
 156         /* Read address values, skipping high cell */
 157         cp = of_read_number(range + 1, na - 1);
 158         s  = of_read_number(range + na + pna, ns);
 159         da = of_read_number(addr + 1, na - 1);
 160
 161         pr_debug("PCI map, cp=%llx, s=%llx, da=%llx\n",
 162                  (unsigned long long)cp, (unsigned long long)s,
 163                  (unsigned long long)da);
 164
 165         if (da < cp || da >= (cp + s))
 166                 return OF_BAD_ADDR;
 167         return da - cp;
 168 }
 169
 170 static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
 171 {
 172         return of_bus_default_translate(addr + 1, offset, na - 1);
 173 }
 174 #endif /* CONFIG_OF_ADDRESS_PCI */
 175
 176 #ifdef CONFIG_PCI
 177 const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
 178                         unsigned int *flags)
 179 {
 180         const __be32 *prop;
 181         unsigned int psize;
 182         struct device_node *parent;
 183         struct of_bus *bus;
 184         int onesize, i, na, ns;
 185
 186         /* Get parent & match bus type */
 187         parent = of_get_parent(dev);
 188         if (parent == NULL)
 189                 return NULL;
 190         bus = of_match_bus(parent);
 191         if (strcmp(bus->name, "pci")) {
 192                 of_node_put(parent);
 193                 return NULL;
 194         }
 195         bus->count_cells(dev, &na, &ns);
 196         of_node_put(parent);
 197         if (!OF_CHECK_ADDR_COUNT(na))
 198                 return NULL;
 199
 200         /* Get "reg" or "assigned-addresses" property */
 201         prop = of_get_property(dev, bus->addresses, &psize);
 202         if (prop == NULL)
 203                 return NULL;
 204         psize /= 4;
 205
 206         onesize = na + ns;
 207         for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
 208                 u32 val = be32_to_cpu(prop[0]);
 209                 if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
 210                         if (size)
 211                                 *size = of_read_number(prop + na, ns);
 212                         if (flags)
 213                                 *flags = bus->get_flags(prop);
 214                         return prop;
 215                 }
 216         }
 217         return NULL;
 218 }
 219 EXPORT_SYMBOL(of_get_pci_address);
 220
 221 int of_pci_address_to_resource(struct device_node *dev, int bar,
 222                                struct resource *r)
 223 {
 224         const __be32    *addrp;
 225         u64             size;
 226         unsigned int    flags;
 227
 228         addrp = of_get_pci_address(dev, bar, &size, &flags);
 229         if (addrp == NULL)
 230                 return -EINVAL;
 231         return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
 232 }
 233 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
 234
 235 int of_pci_range_parser_init(struct of_pci_range_parser *parser,
 236                                 struct device_node *node)
 237 {
 238         const int na = 3, ns = 2;
 239         int rlen;
 240
 241         parser->node = node;
 242         parser->pna = of_n_addr_cells(node);
 243         parser->np = parser->pna + na + ns;
 244
 245         parser->range = of_get_property(node, "ranges", &rlen);
 246         if (parser->range == NULL)
 247                 return -ENOENT;
 248
 249         parser->end = parser->range + rlen / sizeof(__be32);
 250
 251         return 0;
 252 }
 253 EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
 254
 255 struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
 256                                                 struct of_pci_range *range)
 257 {
 258         const int na = 3, ns = 2;
 259
 260         if (!range)
 261                 return NULL;
 262
 263         if (!parser->range || parser->range + parser->np > parser->end)
 264                 return NULL;
 265
 266         range->pci_space = parser->range[0];
 267         range->flags = of_bus_pci_get_flags(parser->range);
 268         range->pci_addr = of_read_number(parser->range + 1, ns);
 269         range->cpu_addr = of_translate_address(parser->node,
 270                                 parser->range + na);
 271         range->size = of_read_number(parser->range + parser->pna + na, ns);
 272
 273         parser->range += parser->np;
 274
 275         /* Now consume following elements while they are contiguous */
 276         while (parser->range + parser->np <= parser->end) {
 277                 u32 flags, pci_space;
 278                 u64 pci_addr, cpu_addr, size;
 279
 280                 pci_space = be32_to_cpup(parser->range);
 281                 flags = of_bus_pci_get_flags(parser->range);
 282                 pci_addr = of_read_number(parser->range + 1, ns);
 283                 cpu_addr = of_translate_address(parser->node,
 284                                 parser->range + na);
 285                 size = of_read_number(parser->range + parser->pna + na, ns);
 286
 287                 if (flags != range->flags)
 288                         break;
 289                 if (pci_addr != range->pci_addr + range->size ||
 290                     cpu_addr != range->cpu_addr + range->size)
 291                         break;
 292
 293                 range->size += size;
 294                 parser->range += parser->np;
 295         }
 296
 297         return range;
 298 }
 299 EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
 300
 301 /*
 302  * of_pci_range_to_resource - Create a resource from an of_pci_range
 303  * @range:      the PCI range that describes the resource
 304  * @np:         device node where the range belongs to
 305  * @res:        pointer to a valid resource that will be updated to
 306  *              reflect the values contained in the range.
 307  *
 308  * Returns EINVAL if the range cannot be converted to resource.
 309  *
 310  * Note that if the range is an IO range, the resource will be converted
 311  * using pci_address_to_pio() which can fail if it is called too early or
 312  * if the range cannot be matched to any host bridge IO space (our case here).
 313  * To guard against that we try to register the IO range first.
 314  * If that fails we know that pci_address_to_pio() will do too.
 315  */
 316 int of_pci_range_to_resource(struct of_pci_range *range,
 317                              struct device_node *np, struct resource *res)
 318 {
 319         int err;
 320         res->flags = range->flags;
 321         res->parent = res->child = res->sibling = NULL;
 322         res->name = np->full_name;
 323
 324         if (res->flags & IORESOURCE_IO) {
 325                 unsigned long port;
 326                 err = pci_register_io_range(range->cpu_addr, range->size);
 327                 if (err)
 328                         goto invalid_range;
 329                 port = pci_address_to_pio(range->cpu_addr);
 330                 if (port == (unsigned long)-1) {
 331                         err = -EINVAL;
 332                         goto invalid_range;
 333                 }
 334                 res->start = port;
 335         } else {
 336                 if ((sizeof(resource_size_t) < 8) &&
 337                     upper_32_bits(range->cpu_addr)) {
 338                         err = -EINVAL;
 339                         goto invalid_range;
 340                 }
 341
 342                 res->start = range->cpu_addr;
 343         }
 344         res->end = res->start + range->size - 1;
 345         return 0;
 346
 347 invalid_range:
 348         res->start = (resource_size_t)OF_BAD_ADDR;
 349         res->end = (resource_size_t)OF_BAD_ADDR;
 350         return err;
 351 }
 352 #endif /* CONFIG_PCI */
 353
 354 /*
 355  * ISA bus specific translator
 356  */
 357
 358 static int of_bus_isa_match(struct device_node *np)
 359 {
 360         return !strcmp(np->name, "isa");
 361 }
 362
 363 static void of_bus_isa_count_cells(struct device_node *child,
 364                                    int *addrc, int *sizec)
 365 {
 366         if (addrc)
 367                 *addrc = 2;
 368         if (sizec)
 369                 *sizec = 1;
 370 }
 371
 372 static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
 373                 int pna)
 374 {
 375         u64 cp, s, da;
 376
 377         /* Check address type match */
 378         if ((addr[0] ^ range[0]) & cpu_to_be32(1))
 379                 return OF_BAD_ADDR;
 380
 381         /* Read address values, skipping high cell */
 382         cp = of_read_number(range + 1, na - 1);
 383         s  = of_read_number(range + na + pna, ns);
 384         da = of_read_number(addr + 1, na - 1);
 385
 386         pr_debug("ISA map, cp=%llx, s=%llx, da=%llx\n",
 387                  (unsigned long long)cp, (unsigned long long)s,
 388                  (unsigned long long)da);
 389
 390         if (da < cp || da >= (cp + s))
 391                 return OF_BAD_ADDR;
 392         return da - cp;
 393 }
 394
 395 static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
 396 {
 397         return of_bus_default_translate(addr + 1, offset, na - 1);
 398 }
 399
 400 static unsigned int of_bus_isa_get_flags(const __be32 *addr)
 401 {
 402         unsigned int flags = 0;
 403         u32 w = be32_to_cpup(addr);
 404
 405         if (w & 1)
 406                 flags |= IORESOURCE_IO;
 407         else
 408                 flags |= IORESOURCE_MEM;
 409         return flags;
 410 }
 411
 412 /*
 413  * Array of bus specific translators
 414  */
 415
 416 static struct of_bus of_busses[] = {
 417 #ifdef CONFIG_OF_ADDRESS_PCI
 418         /* PCI */
 419         {
 420                 .name = "pci",
 421                 .addresses = "assigned-addresses",
 422                 .match = of_bus_pci_match,
 423                 .count_cells = of_bus_pci_count_cells,
 424                 .map = of_bus_pci_map,
 425                 .translate = of_bus_pci_translate,
 426                 .get_flags = of_bus_pci_get_flags,
 427         },
 428 #endif /* CONFIG_OF_ADDRESS_PCI */
 429         /* ISA */
 430         {
 431                 .name = "isa",
 432                 .addresses = "reg",
 433                 .match = of_bus_isa_match,
 434                 .count_cells = of_bus_isa_count_cells,
 435                 .map = of_bus_isa_map,
 436                 .translate = of_bus_isa_translate,
 437                 .get_flags = of_bus_isa_get_flags,
 438         },
 439         /* Default */
 440         {
 441                 .name = "default",
 442                 .addresses = "reg",
 443                 .match = NULL,
 444                 .count_cells = of_bus_default_count_cells,
 445                 .map = of_bus_default_map,
 446                 .translate = of_bus_default_translate,
 447                 .get_flags = of_bus_default_get_flags,
 448         },
 449 };
 450
 451 static struct of_bus *of_match_bus(struct device_node *np)
 452 {
 453         int i;
 454
 455         for (i = 0; i < ARRAY_SIZE(of_busses); i++)
 456                 if (!of_busses[i].match || of_busses[i].match(np))
 457                         return &of_busses[i];
 458         BUG();
 459         return NULL;
 460 }
 461
 462 static int of_empty_ranges_quirk(struct device_node *np)
 463 {
 464         if (IS_ENABLED(CONFIG_PPC)) {
 465                 /* To save cycles, we cache the result for global "Mac" setting */
 466                 static int quirk_state = -1;
 467
 468                 /* PA-SEMI sdc DT bug */
 469                 if (of_device_is_compatible(np, "1682m-sdc"))
 470                         return true;
 471
 472                 /* Make quirk cached */
 473                 if (quirk_state < 0)
 474                         quirk_state =
 475                                 of_machine_is_compatible("Power Macintosh") ||
 476                                 of_machine_is_compatible("MacRISC");
 477                 return quirk_state;
 478         }
 479         return false;
 480 }
 481
 482 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
 483                             struct of_bus *pbus, __be32 *addr,
 484                             int na, int ns, int pna, const char *rprop)
 485 {
 486         const __be32 *ranges;
 487         unsigned int rlen;
 488         int rone;
 489         u64 offset = OF_BAD_ADDR;
 490
 491         /*
 492          * Normally, an absence of a "ranges" property means we are
 493          * crossing a non-translatable boundary, and thus the addresses
 494          * below the current cannot be converted to CPU physical ones.
 495          * Unfortunately, while this is very clear in the spec, it's not
 496          * what Apple understood, and they do have things like /uni-n or
 497          * /ht nodes with no "ranges" property and a lot of perfectly
 498          * useable mapped devices below them. Thus we treat the absence of
 499          * "ranges" as equivalent to an empty "ranges" property which means
 500          * a 1:1 translation at that level. It's up to the caller not to try
 501          * to translate addresses that aren't supposed to be translated in
 502          * the first place. --BenH.
 503          *
 504          * As far as we know, this damage only exists on Apple machines, so
 505          * This code is only enabled on powerpc. --gcl
 506          */
 507         ranges = of_get_property(parent, rprop, &rlen);
 508         if (ranges == NULL && !of_empty_ranges_quirk(parent)) {
 509                 pr_debug("no ranges; cannot translate\n");
 510                 return 1;
 511         }
 512         if (ranges == NULL || rlen == 0) {
 513                 offset = of_read_number(addr, na);
 514                 memset(addr, 0, pna * 4);
 515                 pr_debug("empty ranges; 1:1 translation\n");
 516                 goto finish;
 517         }
 518
 519         pr_debug("walking ranges...\n");
 520
 521         /* Now walk through the ranges */
 522         rlen /= 4;
 523         rone = na + pna + ns;
 524         for (; rlen >= rone; rlen -= rone, ranges += rone) {
 525                 offset = bus->map(addr, ranges, na, ns, pna);
 526                 if (offset != OF_BAD_ADDR)
 527                         break;
 528         }
 529         if (offset == OF_BAD_ADDR) {
 530                 pr_debug("not found !\n");
 531                 return 1;
 532         }
 533         memcpy(addr, ranges + na, 4 * pna);
 534
 535  finish:
 536         of_dump_addr("parent translation for:", addr, pna);
 537         pr_debug("with offset: %llx\n", (unsigned long long)offset);
 538
 539         /* Translate it into parent bus space */
 540         return pbus->translate(addr, offset, pna);
 541 }
 542
 543 /*
 544  * Translate an address from the device-tree into a CPU physical address,
 545  * this walks up the tree and applies the various bus mappings on the
 546  * way.
 547  *
 548  * Note: We consider that crossing any level with #size-cells == 0 to mean
 549  * that translation is impossible (that is we are not dealing with a value
 550  * that can be mapped to a cpu physical address). This is not really specified
 551  * that way, but this is traditionally the way IBM at least do things
 552  */
 553 static u64 __of_translate_address(struct device_node *dev,
 554                                   const __be32 *in_addr, const char *rprop)
 555 {
 556         struct device_node *parent = NULL;
 557         struct of_bus *bus, *pbus;
 558         __be32 addr[OF_MAX_ADDR_CELLS];
 559         int na, ns, pna, pns;
 560         u64 result = OF_BAD_ADDR;
 561
 562         pr_debug("** translation for device %s **\n", of_node_full_name(dev));
 563
 564         /* Increase refcount at current level */
 565         of_node_get(dev);
 566
 567         /* Get parent & match bus type */
 568         parent = of_get_parent(dev);
 569         if (parent == NULL)
 570                 goto bail;
 571         bus = of_match_bus(parent);
 572
 573         /* Count address cells & copy address locally */
 574         bus->count_cells(dev, &na, &ns);
 575         if (!OF_CHECK_COUNTS(na, ns)) {
 576                 pr_debug("Bad cell count for %s\n", of_node_full_name(dev));
 577                 goto bail;
 578         }
 579         memcpy(addr, in_addr, na * 4);
 580
 581         pr_debug("bus is %s (na=%d, ns=%d) on %s\n",
 582             bus->name, na, ns, of_node_full_name(parent));
 583         of_dump_addr("translating address:", addr, na);
 584
 585         /* Translate */
 586         for (;;) {
 587                 /* Switch to parent bus */
 588                 of_node_put(dev);
 589                 dev = parent;
 590                 parent = of_get_parent(dev);
 591
 592                 /* If root, we have finished */
 593                 if (parent == NULL) {
 594                         pr_debug("reached root node\n");
 595                         result = of_read_number(addr, na);
 596                         break;
 597                 }
 598
 599                 /* Get new parent bus and counts */
 600                 pbus = of_match_bus(parent);
 601                 pbus->count_cells(dev, &pna, &pns);
 602                 if (!OF_CHECK_COUNTS(pna, pns)) {
 603                         pr_err("Bad cell count for %s\n",
 604                                of_node_full_name(dev));
 605                         break;
 606                 }
 607
 608                 pr_debug("parent bus is %s (na=%d, ns=%d) on %s\n",
 609                     pbus->name, pna, pns, of_node_full_name(parent));
 610
 611                 /* Apply bus translation */
 612                 if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
 613                         break;
 614
 615                 /* Complete the move up one level */
 616                 na = pna;
 617                 ns = pns;
 618                 bus = pbus;
 619
 620                 of_dump_addr("one level translation:", addr, na);
 621         }
 622  bail:
 623         of_node_put(parent);
 624         of_node_put(dev);
 625
 626         return result;
 627 }
 628
 629 u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
 630 {
 631         return __of_translate_address(dev, in_addr, "ranges");
 632 }
 633 EXPORT_SYMBOL(of_translate_address);
 634
 635 u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
 636 {
 637         return __of_translate_address(dev, in_addr, "dma-ranges");
 638 }
 639 EXPORT_SYMBOL(of_translate_dma_address);
 640
 641 const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
 642                     unsigned int *flags)
 643 {
 644         const __be32 *prop;
 645         unsigned int psize;
 646         struct device_node *parent;
 647         struct of_bus *bus;
 648         int onesize, i, na, ns;
 649
 650         /* Get parent & match bus type */
 651         parent = of_get_parent(dev);
 652         if (parent == NULL)
 653                 return NULL;
 654         bus = of_match_bus(parent);
 655         bus->count_cells(dev, &na, &ns);
 656         of_node_put(parent);
 657         if (!OF_CHECK_ADDR_COUNT(na))
 658                 return NULL;
 659
 660         /* Get "reg" or "assigned-addresses" property */
 661         prop = of_get_property(dev, bus->addresses, &psize);
 662         if (prop == NULL)
 663                 return NULL;
 664         psize /= 4;
 665
 666         onesize = na + ns;
 667         for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
 668                 if (i == index) {
 669                         if (size)
 670                                 *size = of_read_number(prop + na, ns);
 671                         if (flags)
 672                                 *flags = bus->get_flags(prop);
 673                         return prop;
 674                 }
 675         return NULL;
 676 }
 677 EXPORT_SYMBOL(of_get_address);
 678
 679 static int __of_address_to_resource(struct device_node *dev,
 680                 const __be32 *addrp, u64 size, unsigned int flags,
 681                 const char *name, struct resource *r)
 682 {
 683         u64 taddr;
 684
 685         if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
 686                 return -EINVAL;
 687         taddr = of_translate_address(dev, addrp);
 688         if (taddr == OF_BAD_ADDR)
 689                 return -EINVAL;
 690         memset(r, 0, sizeof(struct resource));
 691         if (flags & IORESOURCE_IO) {
 692                 unsigned long port;
 693                 port = pci_address_to_pio(taddr);
 694                 if (port == (unsigned long)-1)
 695                         return -EINVAL;
 696                 r->start = port;
 697                 r->end = port + size - 1;
 698         } else {
 699                 r->start = taddr;
 700                 r->end = taddr + size - 1;
 701         }
 702         r->flags = flags;
 703         r->name = name ? name : dev->full_name;
 704
 705         return 0;
 706 }
 707
 708 /**
 709  * of_address_to_resource - Translate device tree address and return as resource
 710  *
 711  * Note that if your address is a PIO address, the conversion will fail if
 712  * the physical address can't be internally converted to an IO token with
 713  * pci_address_to_pio(), that is because it's either called to early or it
 714  * can't be matched to any host bridge IO space
 715  */
 716 int of_address_to_resource(struct device_node *dev, int index,
 717                            struct resource *r)
 718 {
 719         const __be32    *addrp;
 720         u64             size;
 721         unsigned int    flags;
 722         const char      *name = NULL;
 723
 724         addrp = of_get_address(dev, index, &size, &flags);
 725         if (addrp == NULL)
 726                 return -EINVAL;
 727
 728         /* Get optional "reg-names" property to add a name to a resource */
 729         of_property_read_string_index(dev, "reg-names", index, &name);
 730
 731         return __of_address_to_resource(dev, addrp, size, flags, name, r);
 732 }
 733 EXPORT_SYMBOL_GPL(of_address_to_resource);
 734
 735 struct device_node *of_find_matching_node_by_address(struct device_node *from,
 736                                         const struct of_device_id *matches,
 737                                         u64 base_address)
 738 {
 739         struct device_node *dn = of_find_matching_node(from, matches);
 740         struct resource res;
 741
 742         while (dn) {
 743                 if (!of_address_to_resource(dn, 0, &res) &&
 744                     res.start == base_address)
 745                         return dn;
 746
 747                 dn = of_find_matching_node(dn, matches);
 748         }
 749
 750         return NULL;
 751 }
 752
 753
 754 /**
 755  * of_iomap - Maps the memory mapped IO for a given device_node
 756  * @device:     the device whose io range will be mapped
 757  * @index:      index of the io range
 758  *
 759  * Returns a pointer to the mapped memory
 760  */
 761 void __iomem *of_iomap(struct device_node *np, int index)
 762 {
 763         struct resource res;
 764
 765         if (of_address_to_resource(np, index, &res))
 766                 return NULL;
 767
 768         return ioremap(res.start, resource_size(&res));
 769 }
 770 EXPORT_SYMBOL(of_iomap);
 771
 772 /*
 773  * of_io_request_and_map - Requests a resource and maps the memory mapped IO
 774  *                         for a given device_node
 775  * @device:     the device whose io range will be mapped
 776  * @index:      index of the io range
 777  * @name:       name of the resource
 778  *
 779  * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
 780  * error code on failure. Usage example:
 781  *
 782  *      base = of_io_request_and_map(node, 0, "foo");
 783  *      if (IS_ERR(base))
 784  *              return PTR_ERR(base);
 785  */
 786 void __iomem *of_io_request_and_map(struct device_node *np, int index,
 787                                         const char *name)
 788 {
 789         struct resource res;
 790         void __iomem *mem;
 791
 792         if (of_address_to_resource(np, index, &res))
 793                 return IOMEM_ERR_PTR(-EINVAL);
 794
 795         if (!request_mem_region(res.start, resource_size(&res), name))
 796                 return IOMEM_ERR_PTR(-EBUSY);
 797
 798         mem = ioremap(res.start, resource_size(&res));
 799         if (!mem) {
 800                 release_mem_region(res.start, resource_size(&res));
 801                 return IOMEM_ERR_PTR(-ENOMEM);
 802         }
 803
 804         return mem;
 805 }
 806 EXPORT_SYMBOL(of_io_request_and_map);
 807
 808 /**
 809  * of_dma_get_range - Get DMA range info
 810  * @np:         device node to get DMA range info
 811  * @dma_addr:   pointer to store initial DMA address of DMA range
 812  * @paddr:      pointer to store initial CPU address of DMA range
 813  * @size:       pointer to store size of DMA range
 814  *
 815  * Look in bottom up direction for the first "dma-ranges" property
 816  * and parse it.
 817  *  dma-ranges format:
 818  *      DMA addr (dma_addr)     : naddr cells
 819  *      CPU addr (phys_addr_t)  : pna cells
 820  *      size                    : nsize cells
 821  *
 822  * It returns -ENODEV if "dma-ranges" property was not found
 823  * for this device in DT.
 824  */
 825 int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
 826 {
 827         struct device_node *node = of_node_get(np);
 828         const __be32 *ranges = NULL;
 829         int len, naddr, nsize, pna;
 830         int ret = 0;
 831         u64 dmaaddr;
 832
 833         if (!node)
 834                 return -EINVAL;
 835
 836         while (1) {
 837                 naddr = of_n_addr_cells(node);
 838                 nsize = of_n_size_cells(node);
 839                 node = of_get_next_parent(node);
 840                 if (!node)
 841                         break;
 842
 843                 ranges = of_get_property(node, "dma-ranges", &len);
 844
 845                 /* Ignore empty ranges, they imply no translation required */
 846                 if (ranges && len > 0)
 847                         break;
 848
 849                 /*
 850                  * At least empty ranges has to be defined for parent node if
 851                  * DMA is supported
 852                  */
 853                 if (!ranges)
 854                         break;
 855         }
 856
 857         if (!ranges) {
 858                 pr_debug("no dma-ranges found for node(%s)\n", np->full_name);
 859                 ret = -ENODEV;
 860                 goto out;
 861         }
 862
 863         len /= sizeof(u32);
 864
 865         pna = of_n_addr_cells(node);
 866
 867         /* dma-ranges format:
 868          * DMA addr     : naddr cells
 869          * CPU addr     : pna cells
 870          * size         : nsize cells
 871          */
 872         dmaaddr = of_read_number(ranges, naddr);
 873         *paddr = of_translate_dma_address(np, ranges);
 874         if (*paddr == OF_BAD_ADDR) {
 875                 pr_err("translation of DMA address(%pad) to CPU address failed node(%s)\n",
 876                        dma_addr, np->full_name);
 877                 ret = -EINVAL;
 878                 goto out;
 879         }
 880         *dma_addr = dmaaddr;
 881
 882         *size = of_read_number(ranges + naddr + pna, nsize);
 883
 884         pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
 885                  *dma_addr, *paddr, *size);
 886
 887 out:
 888         of_node_put(node);
 889
 890         return ret;
 891 }
 892 EXPORT_SYMBOL_GPL(of_dma_get_range);
 893
 894 /**
 895  * of_dma_is_coherent - Check if device is coherent
 896  * @np: device node
 897  *
 898  * It returns true if "dma-coherent" property was found
 899  * for this device in DT.
 900  */
 901 bool of_dma_is_coherent(struct device_node *np)
 902 {
 903         struct device_node *node = of_node_get(np);
 904
 905         while (node) {
 906                 if (of_property_read_bool(node, "dma-coherent")) {
 907                         of_node_put(node);
 908                         return true;
 909                 }
 910                 node = of_get_next_parent(node);
 911         }
 912         of_node_put(node);
 913         return false;
 914 }
 915 EXPORT_SYMBOL_GPL(of_dma_is_coherent);