drivers/of/address.c

   1 // SPDX-License-Identifier: GPL-2.0
   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_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
 175 const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
 176                         unsigned int *flags)
 177 {
 178         const __be32 *prop;
 179         unsigned int psize;
 180         struct device_node *parent;
 181         struct of_bus *bus;
 182         int onesize, i, na, ns;
 183
 184         /* Get parent & match bus type */
 185         parent = of_get_parent(dev);
 186         if (parent == NULL)
 187                 return NULL;
 188         bus = of_match_bus(parent);
 189         if (strcmp(bus->name, "pci")) {
 190                 of_node_put(parent);
 191                 return NULL;
 192         }
 193         bus->count_cells(dev, &na, &ns);
 194         of_node_put(parent);
 195         if (!OF_CHECK_ADDR_COUNT(na))
 196                 return NULL;
 197
 198         /* Get "reg" or "assigned-addresses" property */
 199         prop = of_get_property(dev, bus->addresses, &psize);
 200         if (prop == NULL)
 201                 return NULL;
 202         psize /= 4;
 203
 204         onesize = na + ns;
 205         for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
 206                 u32 val = be32_to_cpu(prop[0]);
 207                 if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
 208                         if (size)
 209                                 *size = of_read_number(prop + na, ns);
 210                         if (flags)
 211                                 *flags = bus->get_flags(prop);
 212                         return prop;
 213                 }
 214         }
 215         return NULL;
 216 }
 217 EXPORT_SYMBOL(of_get_pci_address);
 218
 219 int of_pci_address_to_resource(struct device_node *dev, int bar,
 220                                struct resource *r)
 221 {
 222         const __be32    *addrp;
 223         u64             size;
 224         unsigned int    flags;
 225
 226         addrp = of_get_pci_address(dev, bar, &size, &flags);
 227         if (addrp == NULL)
 228                 return -EINVAL;
 229         return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
 230 }
 231 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
 232
 233 static int parser_init(struct of_pci_range_parser *parser,
 234                         struct device_node *node, const char *name)
 235 {
 236         const int na = 3, ns = 2;
 237         int rlen;
 238
 239         parser->node = node;
 240         parser->pna = of_n_addr_cells(node);
 241         parser->np = parser->pna + na + ns;
 242
 243         parser->range = of_get_property(node, name, &rlen);
 244         if (parser->range == NULL)
 245                 return -ENOENT;
 246
 247         parser->end = parser->range + rlen / sizeof(__be32);
 248
 249         return 0;
 250 }
 251
 252 int of_pci_range_parser_init(struct of_pci_range_parser *parser,
 253                                 struct device_node *node)
 254 {
 255         return parser_init(parser, node, "ranges");
 256 }
 257 EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
 258
 259 int of_pci_dma_range_parser_init(struct of_pci_range_parser *parser,
 260                                 struct device_node *node)
 261 {
 262         return parser_init(parser, node, "dma-ranges");
 263 }
 264 EXPORT_SYMBOL_GPL(of_pci_dma_range_parser_init);
 265
 266 struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
 267                                                 struct of_pci_range *range)
 268 {
 269         const int na = 3, ns = 2;
 270
 271         if (!range)
 272                 return NULL;
 273
 274         if (!parser->range || parser->range + parser->np > parser->end)
 275                 return NULL;
 276
 277         range->pci_space = be32_to_cpup(parser->range);
 278         range->flags = of_bus_pci_get_flags(parser->range);
 279         range->pci_addr = of_read_number(parser->range + 1, ns);
 280         range->cpu_addr = of_translate_address(parser->node,
 281                                 parser->range + na);
 282         range->size = of_read_number(parser->range + parser->pna + na, ns);
 283
 284         parser->range += parser->np;
 285
 286         /* Now consume following elements while they are contiguous */
 287         while (parser->range + parser->np <= parser->end) {
 288                 u32 flags;
 289                 u64 pci_addr, cpu_addr, size;
 290
 291                 flags = of_bus_pci_get_flags(parser->range);
 292                 pci_addr = of_read_number(parser->range + 1, ns);
 293                 cpu_addr = of_translate_address(parser->node,
 294                                 parser->range + na);
 295                 size = of_read_number(parser->range + parser->pna + na, ns);
 296
 297                 if (flags != range->flags)
 298                         break;
 299                 if (pci_addr != range->pci_addr + range->size ||
 300                     cpu_addr != range->cpu_addr + range->size)
 301                         break;
 302
 303                 range->size += size;
 304                 parser->range += parser->np;
 305         }
 306
 307         return range;
 308 }
 309 EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
 310
 311 /*
 312  * of_pci_range_to_resource - Create a resource from an of_pci_range
 313  * @range:      the PCI range that describes the resource
 314  * @np:         device node where the range belongs to
 315  * @res:        pointer to a valid resource that will be updated to
 316  *              reflect the values contained in the range.
 317  *
 318  * Returns EINVAL if the range cannot be converted to resource.
 319  *
 320  * Note that if the range is an IO range, the resource will be converted
 321  * using pci_address_to_pio() which can fail if it is called too early or
 322  * if the range cannot be matched to any host bridge IO space (our case here).
 323  * To guard against that we try to register the IO range first.
 324  * If that fails we know that pci_address_to_pio() will do too.
 325  */
 326 int of_pci_range_to_resource(struct of_pci_range *range,
 327                              struct device_node *np, struct resource *res)
 328 {
 329         int err;
 330         res->flags = range->flags;
 331         res->parent = res->child = res->sibling = NULL;
 332         res->name = np->full_name;
 333
 334         if (res->flags & IORESOURCE_IO) {
 335                 unsigned long port;
 336                 err = pci_register_io_range(range->cpu_addr, range->size);
 337                 if (err)
 338                         goto invalid_range;
 339                 port = pci_address_to_pio(range->cpu_addr);
 340                 if (port == (unsigned long)-1) {
 341                         err = -EINVAL;
 342                         goto invalid_range;
 343                 }
 344                 res->start = port;
 345         } else {
 346                 if ((sizeof(resource_size_t) < 8) &&
 347                     upper_32_bits(range->cpu_addr)) {
 348                         err = -EINVAL;
 349                         goto invalid_range;
 350                 }
 351
 352                 res->start = range->cpu_addr;
 353         }
 354         res->end = res->start + range->size - 1;
 355         return 0;
 356
 357 invalid_range:
 358         res->start = (resource_size_t)OF_BAD_ADDR;
 359         res->end = (resource_size_t)OF_BAD_ADDR;
 360         return err;
 361 }
 362 EXPORT_SYMBOL(of_pci_range_to_resource);
 363 #endif /* CONFIG_PCI */
 364
 365 /*
 366  * ISA bus specific translator
 367  */
 368
 369 static int of_bus_isa_match(struct device_node *np)
 370 {
 371         return !strcmp(np->name, "isa");
 372 }
 373
 374 static void of_bus_isa_count_cells(struct device_node *child,
 375                                    int *addrc, int *sizec)
 376 {
 377         if (addrc)
 378                 *addrc = 2;
 379         if (sizec)
 380                 *sizec = 1;
 381 }
 382
 383 static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
 384                 int pna)
 385 {
 386         u64 cp, s, da;
 387
 388         /* Check address type match */
 389         if ((addr[0] ^ range[0]) & cpu_to_be32(1))
 390                 return OF_BAD_ADDR;
 391
 392         /* Read address values, skipping high cell */
 393         cp = of_read_number(range + 1, na - 1);
 394         s  = of_read_number(range + na + pna, ns);
 395         da = of_read_number(addr + 1, na - 1);
 396
 397         pr_debug("ISA map, cp=%llx, s=%llx, da=%llx\n",
 398                  (unsigned long long)cp, (unsigned long long)s,
 399                  (unsigned long long)da);
 400
 401         if (da < cp || da >= (cp + s))
 402                 return OF_BAD_ADDR;
 403         return da - cp;
 404 }
 405
 406 static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
 407 {
 408         return of_bus_default_translate(addr + 1, offset, na - 1);
 409 }
 410
 411 static unsigned int of_bus_isa_get_flags(const __be32 *addr)
 412 {
 413         unsigned int flags = 0;
 414         u32 w = be32_to_cpup(addr);
 415
 416         if (w & 1)
 417                 flags |= IORESOURCE_IO;
 418         else
 419                 flags |= IORESOURCE_MEM;
 420         return flags;
 421 }
 422
 423 /*
 424  * Array of bus specific translators
 425  */
 426
 427 static struct of_bus of_busses[] = {
 428 #ifdef CONFIG_PCI
 429         /* PCI */
 430         {
 431                 .name = "pci",
 432                 .addresses = "assigned-addresses",
 433                 .match = of_bus_pci_match,
 434                 .count_cells = of_bus_pci_count_cells,
 435                 .map = of_bus_pci_map,
 436                 .translate = of_bus_pci_translate,
 437                 .get_flags = of_bus_pci_get_flags,
 438         },
 439 #endif /* CONFIG_PCI */
 440         /* ISA */
 441         {
 442                 .name = "isa",
 443                 .addresses = "reg",
 444                 .match = of_bus_isa_match,
 445                 .count_cells = of_bus_isa_count_cells,
 446                 .map = of_bus_isa_map,
 447                 .translate = of_bus_isa_translate,
 448                 .get_flags = of_bus_isa_get_flags,
 449         },
 450         /* Default */
 451         {
 452                 .name = "default",
 453                 .addresses = "reg",
 454                 .match = NULL,
 455                 .count_cells = of_bus_default_count_cells,
 456                 .map = of_bus_default_map,
 457                 .translate = of_bus_default_translate,
 458                 .get_flags = of_bus_default_get_flags,
 459         },
 460 };
 461
 462 static struct of_bus *of_match_bus(struct device_node *np)
 463 {
 464         int i;
 465
 466         for (i = 0; i < ARRAY_SIZE(of_busses); i++)
 467                 if (!of_busses[i].match || of_busses[i].match(np))
 468                         return &of_busses[i];
 469         BUG();
 470         return NULL;
 471 }
 472
 473 static int of_empty_ranges_quirk(struct device_node *np)
 474 {
 475         if (IS_ENABLED(CONFIG_PPC)) {
 476                 /* To save cycles, we cache the result for global "Mac" setting */
 477                 static int quirk_state = -1;
 478
 479                 /* PA-SEMI sdc DT bug */
 480                 if (of_device_is_compatible(np, "1682m-sdc"))
 481                         return true;
 482
 483                 /* Make quirk cached */
 484                 if (quirk_state < 0)
 485                         quirk_state =
 486                                 of_machine_is_compatible("Power Macintosh") ||
 487                                 of_machine_is_compatible("MacRISC");
 488                 return quirk_state;
 489         }
 490         return false;
 491 }
 492
 493 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
 494                             struct of_bus *pbus, __be32 *addr,
 495                             int na, int ns, int pna, const char *rprop)
 496 {
 497         const __be32 *ranges;
 498         unsigned int rlen;
 499         int rone;
 500         u64 offset = OF_BAD_ADDR;
 501
 502         /*
 503          * Normally, an absence of a "ranges" property means we are
 504          * crossing a non-translatable boundary, and thus the addresses
 505          * below the current cannot be converted to CPU physical ones.
 506          * Unfortunately, while this is very clear in the spec, it's not
 507          * what Apple understood, and they do have things like /uni-n or
 508          * /ht nodes with no "ranges" property and a lot of perfectly
 509          * useable mapped devices below them. Thus we treat the absence of
 510          * "ranges" as equivalent to an empty "ranges" property which means
 511          * a 1:1 translation at that level. It's up to the caller not to try
 512          * to translate addresses that aren't supposed to be translated in
 513          * the first place. --BenH.
 514          *
 515          * As far as we know, this damage only exists on Apple machines, so
 516          * This code is only enabled on powerpc. --gcl
 517          */
 518         ranges = of_get_property(parent, rprop, &rlen);
 519         if (ranges == NULL && !of_empty_ranges_quirk(parent)) {
 520                 pr_debug("no ranges; cannot translate\n");
 521                 return 1;
 522         }
 523         if (ranges == NULL || rlen == 0) {
 524                 offset = of_read_number(addr, na);
 525                 memset(addr, 0, pna * 4);
 526                 pr_debug("empty ranges; 1:1 translation\n");
 527                 goto finish;
 528         }
 529
 530         pr_debug("walking ranges...\n");
 531
 532         /* Now walk through the ranges */
 533         rlen /= 4;
 534         rone = na + pna + ns;
 535         for (; rlen >= rone; rlen -= rone, ranges += rone) {
 536                 offset = bus->map(addr, ranges, na, ns, pna);
 537                 if (offset != OF_BAD_ADDR)
 538                         break;
 539         }
 540         if (offset == OF_BAD_ADDR) {
 541                 pr_debug("not found !\n");
 542                 return 1;
 543         }
 544         memcpy(addr, ranges + na, 4 * pna);
 545
 546  finish:
 547         of_dump_addr("parent translation for:", addr, pna);
 548         pr_debug("with offset: %llx\n", (unsigned long long)offset);
 549
 550         /* Translate it into parent bus space */
 551         return pbus->translate(addr, offset, pna);
 552 }
 553
 554 /*
 555  * Translate an address from the device-tree into a CPU physical address,
 556  * this walks up the tree and applies the various bus mappings on the
 557  * way.
 558  *
 559  * Note: We consider that crossing any level with #size-cells == 0 to mean
 560  * that translation is impossible (that is we are not dealing with a value
 561  * that can be mapped to a cpu physical address). This is not really specified
 562  * that way, but this is traditionally the way IBM at least do things
 563  */
 564 static u64 __of_translate_address(struct device_node *dev,
 565                                   const __be32 *in_addr, const char *rprop)
 566 {
 567         struct device_node *parent = NULL;
 568         struct of_bus *bus, *pbus;
 569         __be32 addr[OF_MAX_ADDR_CELLS];
 570         int na, ns, pna, pns;
 571         u64 result = OF_BAD_ADDR;
 572
 573         pr_debug("** translation for device %pOF **\n", dev);
 574
 575         /* Increase refcount at current level */
 576         of_node_get(dev);
 577
 578         /* Get parent & match bus type */
 579         parent = of_get_parent(dev);
 580         if (parent == NULL)
 581                 goto bail;
 582         bus = of_match_bus(parent);
 583
 584         /* Count address cells & copy address locally */
 585         bus->count_cells(dev, &na, &ns);
 586         if (!OF_CHECK_COUNTS(na, ns)) {
 587                 pr_debug("Bad cell count for %pOF\n", dev);
 588                 goto bail;
 589         }
 590         memcpy(addr, in_addr, na * 4);
 591
 592         pr_debug("bus is %s (na=%d, ns=%d) on %pOF\n",
 593             bus->name, na, ns, parent);
 594         of_dump_addr("translating address:", addr, na);
 595
 596         /* Translate */
 597         for (;;) {
 598                 /* Switch to parent bus */
 599                 of_node_put(dev);
 600                 dev = parent;
 601                 parent = of_get_parent(dev);
 602
 603                 /* If root, we have finished */
 604                 if (parent == NULL) {
 605                         pr_debug("reached root node\n");
 606                         result = of_read_number(addr, na);
 607                         break;
 608                 }
 609
 610                 /* Get new parent bus and counts */
 611                 pbus = of_match_bus(parent);
 612                 pbus->count_cells(dev, &pna, &pns);
 613                 if (!OF_CHECK_COUNTS(pna, pns)) {
 614                         pr_err("Bad cell count for %pOF\n", dev);
 615                         break;
 616                 }
 617
 618                 pr_debug("parent bus is %s (na=%d, ns=%d) on %pOF\n",
 619                     pbus->name, pna, pns, parent);
 620
 621                 /* Apply bus translation */
 622                 if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
 623                         break;
 624
 625                 /* Complete the move up one level */
 626                 na = pna;
 627                 ns = pns;
 628                 bus = pbus;
 629
 630                 of_dump_addr("one level translation:", addr, na);
 631         }
 632  bail:
 633         of_node_put(parent);
 634         of_node_put(dev);
 635
 636         return result;
 637 }
 638
 639 u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
 640 {
 641         return __of_translate_address(dev, in_addr, "ranges");
 642 }
 643 EXPORT_SYMBOL(of_translate_address);
 644
 645 u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
 646 {
 647         return __of_translate_address(dev, in_addr, "dma-ranges");
 648 }
 649 EXPORT_SYMBOL(of_translate_dma_address);
 650
 651 const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
 652                     unsigned int *flags)
 653 {
 654         const __be32 *prop;
 655         unsigned int psize;
 656         struct device_node *parent;
 657         struct of_bus *bus;
 658         int onesize, i, na, ns;
 659
 660         /* Get parent & match bus type */
 661         parent = of_get_parent(dev);
 662         if (parent == NULL)
 663                 return NULL;
 664         bus = of_match_bus(parent);
 665         bus->count_cells(dev, &na, &ns);
 666         of_node_put(parent);
 667         if (!OF_CHECK_ADDR_COUNT(na))
 668                 return NULL;
 669
 670         /* Get "reg" or "assigned-addresses" property */
 671         prop = of_get_property(dev, bus->addresses, &psize);
 672         if (prop == NULL)
 673                 return NULL;
 674         psize /= 4;
 675
 676         onesize = na + ns;
 677         for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
 678                 if (i == index) {
 679                         if (size)
 680                                 *size = of_read_number(prop + na, ns);
 681                         if (flags)
 682                                 *flags = bus->get_flags(prop);
 683                         return prop;
 684                 }
 685         return NULL;
 686 }
 687 EXPORT_SYMBOL(of_get_address);
 688
 689 static int __of_address_to_resource(struct device_node *dev,
 690                 const __be32 *addrp, u64 size, unsigned int flags,
 691                 const char *name, struct resource *r)
 692 {
 693         u64 taddr;
 694
 695         if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
 696                 return -EINVAL;
 697         taddr = of_translate_address(dev, addrp);
 698         if (taddr == OF_BAD_ADDR)
 699                 return -EINVAL;
 700         memset(r, 0, sizeof(struct resource));
 701         if (flags & IORESOURCE_IO) {
 702                 unsigned long port;
 703                 port = pci_address_to_pio(taddr);
 704                 if (port == (unsigned long)-1)
 705                         return -EINVAL;
 706                 r->start = port;
 707                 r->end = port + size - 1;
 708         } else {
 709                 r->start = taddr;
 710                 r->end = taddr + size - 1;
 711         }
 712         r->flags = flags;
 713         r->name = name ? name : dev->full_name;
 714
 715         return 0;
 716 }
 717
 718 /**
 719  * of_address_to_resource - Translate device tree address and return as resource
 720  *
 721  * Note that if your address is a PIO address, the conversion will fail if
 722  * the physical address can't be internally converted to an IO token with
 723  * pci_address_to_pio(), that is because it's either called too early or it
 724  * can't be matched to any host bridge IO space
 725  */
 726 int of_address_to_resource(struct device_node *dev, int index,
 727                            struct resource *r)
 728 {
 729         const __be32    *addrp;
 730         u64             size;
 731         unsigned int    flags;
 732         const char      *name = NULL;
 733
 734         addrp = of_get_address(dev, index, &size, &flags);
 735         if (addrp == NULL)
 736                 return -EINVAL;
 737
 738         /* Get optional "reg-names" property to add a name to a resource */
 739         of_property_read_string_index(dev, "reg-names", index, &name);
 740
 741         return __of_address_to_resource(dev, addrp, size, flags, name, r);
 742 }
 743 EXPORT_SYMBOL_GPL(of_address_to_resource);
 744
 745 struct device_node *of_find_matching_node_by_address(struct device_node *from,
 746                                         const struct of_device_id *matches,
 747                                         u64 base_address)
 748 {
 749         struct device_node *dn = of_find_matching_node(from, matches);
 750         struct resource res;
 751
 752         while (dn) {
 753                 if (!of_address_to_resource(dn, 0, &res) &&
 754                     res.start == base_address)
 755                         return dn;
 756
 757                 dn = of_find_matching_node(dn, matches);
 758         }
 759
 760         return NULL;
 761 }
 762
 763
 764 /**
 765  * of_iomap - Maps the memory mapped IO for a given device_node
 766  * @device:     the device whose io range will be mapped
 767  * @index:      index of the io range
 768  *
 769  * Returns a pointer to the mapped memory
 770  */
 771 void __iomem *of_iomap(struct device_node *np, int index)
 772 {
 773         struct resource res;
 774
 775         if (of_address_to_resource(np, index, &res))
 776                 return NULL;
 777
 778         return ioremap(res.start, resource_size(&res));
 779 }
 780 EXPORT_SYMBOL(of_iomap);
 781
 782 /*
 783  * of_io_request_and_map - Requests a resource and maps the memory mapped IO
 784  *                         for a given device_node
 785  * @device:     the device whose io range will be mapped
 786  * @index:      index of the io range
 787  * @name:       name of the resource
 788  *
 789  * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
 790  * error code on failure. Usage example:
 791  *
 792  *      base = of_io_request_and_map(node, 0, "foo");
 793  *      if (IS_ERR(base))
 794  *              return PTR_ERR(base);
 795  */
 796 void __iomem *of_io_request_and_map(struct device_node *np, int index,
 797                                         const char *name)
 798 {
 799         struct resource res;
 800         void __iomem *mem;
 801
 802         if (of_address_to_resource(np, index, &res))
 803                 return IOMEM_ERR_PTR(-EINVAL);
 804
 805         if (!request_mem_region(res.start, resource_size(&res), name))
 806                 return IOMEM_ERR_PTR(-EBUSY);
 807
 808         mem = ioremap(res.start, resource_size(&res));
 809         if (!mem) {
 810                 release_mem_region(res.start, resource_size(&res));
 811                 return IOMEM_ERR_PTR(-ENOMEM);
 812         }
 813
 814         return mem;
 815 }
 816 EXPORT_SYMBOL(of_io_request_and_map);
 817
 818 /**
 819  * of_dma_get_range - Get DMA range info
 820  * @np:         device node to get DMA range info
 821  * @dma_addr:   pointer to store initial DMA address of DMA range
 822  * @paddr:      pointer to store initial CPU address of DMA range
 823  * @size:       pointer to store size of DMA range
 824  *
 825  * Look in bottom up direction for the first "dma-ranges" property
 826  * and parse it.
 827  *  dma-ranges format:
 828  *      DMA addr (dma_addr)     : naddr cells
 829  *      CPU addr (phys_addr_t)  : pna cells
 830  *      size                    : nsize cells
 831  *
 832  * It returns -ENODEV if "dma-ranges" property was not found
 833  * for this device in DT.
 834  */
 835 int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
 836 {
 837         struct device_node *node = of_node_get(np);
 838         const __be32 *ranges = NULL;
 839         int len, naddr, nsize, pna;
 840         int ret = 0;
 841         u64 dmaaddr;
 842
 843         if (!node)
 844                 return -EINVAL;
 845
 846         while (1) {
 847                 naddr = of_n_addr_cells(node);
 848                 nsize = of_n_size_cells(node);
 849                 node = of_get_next_parent(node);
 850                 if (!node)
 851                         break;
 852
 853                 ranges = of_get_property(node, "dma-ranges", &len);
 854
 855                 /* Ignore empty ranges, they imply no translation required */
 856                 if (ranges && len > 0)
 857                         break;
 858
 859                 /*
 860                  * At least empty ranges has to be defined for parent node if
 861                  * DMA is supported
 862                  */
 863                 if (!ranges)
 864                         break;
 865         }
 866
 867         if (!ranges) {
 868                 pr_debug("no dma-ranges found for node(%pOF)\n", np);
 869                 ret = -ENODEV;
 870                 goto out;
 871         }
 872
 873         len /= sizeof(u32);
 874
 875         pna = of_n_addr_cells(node);
 876
 877         /* dma-ranges format:
 878          * DMA addr     : naddr cells
 879          * CPU addr     : pna cells
 880          * size         : nsize cells
 881          */
 882         dmaaddr = of_read_number(ranges, naddr);
 883         *paddr = of_translate_dma_address(np, ranges);
 884         if (*paddr == OF_BAD_ADDR) {
 885                 pr_err("translation of DMA address(%pad) to CPU address failed node(%pOF)\n",
 886                        dma_addr, np);
 887                 ret = -EINVAL;
 888                 goto out;
 889         }
 890         *dma_addr = dmaaddr;
 891
 892         *size = of_read_number(ranges + naddr + pna, nsize);
 893
 894         pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
 895                  *dma_addr, *paddr, *size);
 896
 897 out:
 898         of_node_put(node);
 899
 900         return ret;
 901 }
 902 EXPORT_SYMBOL_GPL(of_dma_get_range);
 903
 904 /**
 905  * of_dma_is_coherent - Check if device is coherent
 906  * @np: device node
 907  *
 908  * It returns true if "dma-coherent" property was found
 909  * for this device in DT.
 910  */
 911 bool of_dma_is_coherent(struct device_node *np)
 912 {
 913         struct device_node *node = of_node_get(np);
 914
 915         while (node) {
 916                 if (of_property_read_bool(node, "dma-coherent")) {
 917                         of_node_put(node);
 918                         return true;
 919                 }
 920                 node = of_get_next_parent(node);
 921         }
 922         of_node_put(node);
 923         return false;
 924 }
 925 EXPORT_SYMBOL_GPL(of_dma_is_coherent);