drivers/of/address.c

   1
   2 #include <linux/device.h>
   3 #include <linux/io.h>
   4 #include <linux/ioport.h>
   5 #include <linux/module.h>
   6 #include <linux/of_address.h>
   7 #include <linux/pci_regs.h>
   8 #include <linux/string.h>
   9
  10 /* Max address size we deal with */
  11 #define OF_MAX_ADDR_CELLS       4
  12 #define OF_CHECK_ADDR_COUNT(na) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
  13 #define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
  14
  15 static struct of_bus *of_match_bus(struct device_node *np);
  16 static int __of_address_to_resource(struct device_node *dev,
  17                 const __be32 *addrp, u64 size, unsigned int flags,
  18                 const char *name, struct resource *r);
  19
  20 /* Debug utility */
  21 #ifdef DEBUG
  22 static void of_dump_addr(const char *s, const __be32 *addr, int na)
  23 {
  24         printk(KERN_DEBUG "%s", s);
  25         while (na--)
  26                 printk(" %08x", be32_to_cpu(*(addr++)));
  27         printk("\n");
  28 }
  29 #else
  30 static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
  31 #endif
  32
  33 /* Callbacks for bus specific translators */
  34 struct of_bus {
  35         const char      *name;
  36         const char      *addresses;
  37         int             (*match)(struct device_node *parent);
  38         void            (*count_cells)(struct device_node *child,
  39                                        int *addrc, int *sizec);
  40         u64             (*map)(__be32 *addr, const __be32 *range,
  41                                 int na, int ns, int pna);
  42         int             (*translate)(__be32 *addr, u64 offset, int na);
  43         unsigned int    (*get_flags)(const __be32 *addr);
  44 };
  45
  46 /*
  47  * Default translator (generic bus)
  48  */
  49
  50 static void of_bus_default_count_cells(struct device_node *dev,
  51                                        int *addrc, int *sizec)
  52 {
  53         if (addrc)
  54                 *addrc = of_n_addr_cells(dev);
  55         if (sizec)
  56                 *sizec = of_n_size_cells(dev);
  57 }
  58
  59 static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
  60                 int na, int ns, int pna)
  61 {
  62         u64 cp, s, da;
  63
  64         cp = of_read_number(range, na);
  65         s  = of_read_number(range + na + pna, ns);
  66         da = of_read_number(addr, na);
  67
  68         pr_debug("OF: default map, cp=%llx, s=%llx, da=%llx\n",
  69                  (unsigned long long)cp, (unsigned long long)s,
  70                  (unsigned long long)da);
  71
  72         /*
  73          * If the number of address cells is larger than 2 we assume the
  74          * mapping doesn't specify a physical address. Rather, the address
  75          * specifies an identifier that must match exactly.
  76          */
  77         if (na > 2 && memcmp(range, addr, na * 4) != 0)
  78                 return OF_BAD_ADDR;
  79
  80         if (da < cp || da >= (cp + s))
  81                 return OF_BAD_ADDR;
  82         return da - cp;
  83 }
  84
  85 static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
  86 {
  87         u64 a = of_read_number(addr, na);
  88         memset(addr, 0, na * 4);
  89         a += offset;
  90         if (na > 1)
  91                 addr[na - 2] = cpu_to_be32(a >> 32);
  92         addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
  93
  94         return 0;
  95 }
  96
  97 static unsigned int of_bus_default_get_flags(const __be32 *addr)
  98 {
  99         return IORESOURCE_MEM;
 100 }
 101
 102 #ifdef CONFIG_PCI
 103 /*
 104  * PCI bus specific translator
 105  */
 106
 107 static int of_bus_pci_match(struct device_node *np)
 108 {
 109         /* "vci" is for the /chaos bridge on 1st-gen PCI powermacs */
 110         return !strcmp(np->type, "pci") || !strcmp(np->type, "vci");
 111 }
 112
 113 static void of_bus_pci_count_cells(struct device_node *np,
 114                                    int *addrc, int *sizec)
 115 {
 116         if (addrc)
 117                 *addrc = 3;
 118         if (sizec)
 119                 *sizec = 2;
 120 }
 121
 122 static unsigned int of_bus_pci_get_flags(const __be32 *addr)
 123 {
 124         unsigned int flags = 0;
 125         u32 w = be32_to_cpup(addr);
 126
 127         switch((w >> 24) & 0x03) {
 128         case 0x01:
 129                 flags |= IORESOURCE_IO;
 130                 break;
 131         case 0x02: /* 32 bits */
 132         case 0x03: /* 64 bits */
 133                 flags |= IORESOURCE_MEM;
 134                 break;
 135         }
 136         if (w & 0x40000000)
 137                 flags |= IORESOURCE_PREFETCH;
 138         return flags;
 139 }
 140
 141 static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
 142                 int pna)
 143 {
 144         u64 cp, s, da;
 145         unsigned int af, rf;
 146
 147         af = of_bus_pci_get_flags(addr);
 148         rf = of_bus_pci_get_flags(range);
 149
 150         /* Check address type match */
 151         if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
 152                 return OF_BAD_ADDR;
 153
 154         /* Read address values, skipping high cell */
 155         cp = of_read_number(range + 1, na - 1);
 156         s  = of_read_number(range + na + pna, ns);
 157         da = of_read_number(addr + 1, na - 1);
 158
 159         pr_debug("OF: PCI map, cp=%llx, s=%llx, da=%llx\n",
 160                  (unsigned long long)cp, (unsigned long long)s,
 161                  (unsigned long long)da);
 162
 163         if (da < cp || da >= (cp + s))
 164                 return OF_BAD_ADDR;
 165         return da - cp;
 166 }
 167
 168 static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
 169 {
 170         return of_bus_default_translate(addr + 1, offset, na - 1);
 171 }
 172
 173 const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
 174                         unsigned int *flags)
 175 {
 176         const __be32 *prop;
 177         unsigned int psize;
 178         struct device_node *parent;
 179         struct of_bus *bus;
 180         int onesize, i, na, ns;
 181
 182         /* Get parent & match bus type */
 183         parent = of_get_parent(dev);
 184         if (parent == NULL)
 185                 return NULL;
 186         bus = of_match_bus(parent);
 187         if (strcmp(bus->name, "pci")) {
 188                 of_node_put(parent);
 189                 return NULL;
 190         }
 191         bus->count_cells(dev, &na, &ns);
 192         of_node_put(parent);
 193         if (!OF_CHECK_ADDR_COUNT(na))
 194                 return NULL;
 195
 196         /* Get "reg" or "assigned-addresses" property */
 197         prop = of_get_property(dev, bus->addresses, &psize);
 198         if (prop == NULL)
 199                 return NULL;
 200         psize /= 4;
 201
 202         onesize = na + ns;
 203         for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
 204                 u32 val = be32_to_cpu(prop[0]);
 205                 if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
 206                         if (size)
 207                                 *size = of_read_number(prop + na, ns);
 208                         if (flags)
 209                                 *flags = bus->get_flags(prop);
 210                         return prop;
 211                 }
 212         }
 213         return NULL;
 214 }
 215 EXPORT_SYMBOL(of_get_pci_address);
 216
 217 int of_pci_address_to_resource(struct device_node *dev, int bar,
 218                                struct resource *r)
 219 {
 220         const __be32    *addrp;
 221         u64             size;
 222         unsigned int    flags;
 223
 224         addrp = of_get_pci_address(dev, bar, &size, &flags);
 225         if (addrp == NULL)
 226                 return -EINVAL;
 227         return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
 228 }
 229 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
 230 #endif /* CONFIG_PCI */
 231
 232 /*
 233  * ISA bus specific translator
 234  */
 235
 236 static int of_bus_isa_match(struct device_node *np)
 237 {
 238         return !strcmp(np->name, "isa");
 239 }
 240
 241 static void of_bus_isa_count_cells(struct device_node *child,
 242                                    int *addrc, int *sizec)
 243 {
 244         if (addrc)
 245                 *addrc = 2;
 246         if (sizec)
 247                 *sizec = 1;
 248 }
 249
 250 static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
 251                 int pna)
 252 {
 253         u64 cp, s, da;
 254
 255         /* Check address type match */
 256         if ((addr[0] ^ range[0]) & cpu_to_be32(1))
 257                 return OF_BAD_ADDR;
 258
 259         /* Read address values, skipping high cell */
 260         cp = of_read_number(range + 1, na - 1);
 261         s  = of_read_number(range + na + pna, ns);
 262         da = of_read_number(addr + 1, na - 1);
 263
 264         pr_debug("OF: ISA map, cp=%llx, s=%llx, da=%llx\n",
 265                  (unsigned long long)cp, (unsigned long long)s,
 266                  (unsigned long long)da);
 267
 268         if (da < cp || da >= (cp + s))
 269                 return OF_BAD_ADDR;
 270         return da - cp;
 271 }
 272
 273 static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
 274 {
 275         return of_bus_default_translate(addr + 1, offset, na - 1);
 276 }
 277
 278 static unsigned int of_bus_isa_get_flags(const __be32 *addr)
 279 {
 280         unsigned int flags = 0;
 281         u32 w = be32_to_cpup(addr);
 282
 283         if (w & 1)
 284                 flags |= IORESOURCE_IO;
 285         else
 286                 flags |= IORESOURCE_MEM;
 287         return flags;
 288 }
 289
 290 /*
 291  * Array of bus specific translators
 292  */
 293
 294 static struct of_bus of_busses[] = {
 295 #ifdef CONFIG_PCI
 296         /* PCI */
 297         {
 298                 .name = "pci",
 299                 .addresses = "assigned-addresses",
 300                 .match = of_bus_pci_match,
 301                 .count_cells = of_bus_pci_count_cells,
 302                 .map = of_bus_pci_map,
 303                 .translate = of_bus_pci_translate,
 304                 .get_flags = of_bus_pci_get_flags,
 305         },
 306 #endif /* CONFIG_PCI */
 307         /* ISA */
 308         {
 309                 .name = "isa",
 310                 .addresses = "reg",
 311                 .match = of_bus_isa_match,
 312                 .count_cells = of_bus_isa_count_cells,
 313                 .map = of_bus_isa_map,
 314                 .translate = of_bus_isa_translate,
 315                 .get_flags = of_bus_isa_get_flags,
 316         },
 317         /* Default */
 318         {
 319                 .name = "default",
 320                 .addresses = "reg",
 321                 .match = NULL,
 322                 .count_cells = of_bus_default_count_cells,
 323                 .map = of_bus_default_map,
 324                 .translate = of_bus_default_translate,
 325                 .get_flags = of_bus_default_get_flags,
 326         },
 327 };
 328
 329 static struct of_bus *of_match_bus(struct device_node *np)
 330 {
 331         int i;
 332
 333         for (i = 0; i < ARRAY_SIZE(of_busses); i++)
 334                 if (!of_busses[i].match || of_busses[i].match(np))
 335                         return &of_busses[i];
 336         BUG();
 337         return NULL;
 338 }
 339
 340 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
 341                             struct of_bus *pbus, __be32 *addr,
 342                             int na, int ns, int pna, const char *rprop)
 343 {
 344         const __be32 *ranges;
 345         unsigned int rlen;
 346         int rone;
 347         u64 offset = OF_BAD_ADDR;
 348
 349         /* Normally, an absence of a "ranges" property means we are
 350          * crossing a non-translatable boundary, and thus the addresses
 351          * below the current not cannot be converted to CPU physical ones.
 352          * Unfortunately, while this is very clear in the spec, it's not
 353          * what Apple understood, and they do have things like /uni-n or
 354          * /ht nodes with no "ranges" property and a lot of perfectly
 355          * useable mapped devices below them. Thus we treat the absence of
 356          * "ranges" as equivalent to an empty "ranges" property which means
 357          * a 1:1 translation at that level. It's up to the caller not to try
 358          * to translate addresses that aren't supposed to be translated in
 359          * the first place. --BenH.
 360          *
 361          * As far as we know, this damage only exists on Apple machines, so
 362          * This code is only enabled on powerpc. --gcl
 363          */
 364         ranges = of_get_property(parent, rprop, &rlen);
 365 #if !defined(CONFIG_PPC)
 366         if (ranges == NULL) {
 367                 pr_err("OF: no ranges; cannot translate\n");
 368                 return 1;
 369         }
 370 #endif /* !defined(CONFIG_PPC) */
 371         if (ranges == NULL || rlen == 0) {
 372                 offset = of_read_number(addr, na);
 373                 memset(addr, 0, pna * 4);
 374                 pr_debug("OF: empty ranges; 1:1 translation\n");
 375                 goto finish;
 376         }
 377
 378         pr_debug("OF: walking ranges...\n");
 379
 380         /* Now walk through the ranges */
 381         rlen /= 4;
 382         rone = na + pna + ns;
 383         for (; rlen >= rone; rlen -= rone, ranges += rone) {
 384                 offset = bus->map(addr, ranges, na, ns, pna);
 385                 if (offset != OF_BAD_ADDR)
 386                         break;
 387         }
 388         if (offset == OF_BAD_ADDR) {
 389                 pr_debug("OF: not found !\n");
 390                 return 1;
 391         }
 392         memcpy(addr, ranges + na, 4 * pna);
 393
 394  finish:
 395         of_dump_addr("OF: parent translation for:", addr, pna);
 396         pr_debug("OF: with offset: %llx\n", (unsigned long long)offset);
 397
 398         /* Translate it into parent bus space */
 399         return pbus->translate(addr, offset, pna);
 400 }
 401
 402 /*
 403  * Translate an address from the device-tree into a CPU physical address,
 404  * this walks up the tree and applies the various bus mappings on the
 405  * way.
 406  *
 407  * Note: We consider that crossing any level with #size-cells == 0 to mean
 408  * that translation is impossible (that is we are not dealing with a value
 409  * that can be mapped to a cpu physical address). This is not really specified
 410  * that way, but this is traditionally the way IBM at least do things
 411  */
 412 static u64 __of_translate_address(struct device_node *dev,
 413                                   const __be32 *in_addr, const char *rprop)
 414 {
 415         struct device_node *parent = NULL;
 416         struct of_bus *bus, *pbus;
 417         __be32 addr[OF_MAX_ADDR_CELLS];
 418         int na, ns, pna, pns;
 419         u64 result = OF_BAD_ADDR;
 420
 421         pr_debug("OF: ** translation for device %s **\n", dev->full_name);
 422
 423         /* Increase refcount at current level */
 424         of_node_get(dev);
 425
 426         /* Get parent & match bus type */
 427         parent = of_get_parent(dev);
 428         if (parent == NULL)
 429                 goto bail;
 430         bus = of_match_bus(parent);
 431
 432         /* Cound address cells & copy address locally */
 433         bus->count_cells(dev, &na, &ns);
 434         if (!OF_CHECK_COUNTS(na, ns)) {
 435                 printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
 436                        dev->full_name);
 437                 goto bail;
 438         }
 439         memcpy(addr, in_addr, na * 4);
 440
 441         pr_debug("OF: bus is %s (na=%d, ns=%d) on %s\n",
 442             bus->name, na, ns, parent->full_name);
 443         of_dump_addr("OF: translating address:", addr, na);
 444
 445         /* Translate */
 446         for (;;) {
 447                 /* Switch to parent bus */
 448                 of_node_put(dev);
 449                 dev = parent;
 450                 parent = of_get_parent(dev);
 451
 452                 /* If root, we have finished */
 453                 if (parent == NULL) {
 454                         pr_debug("OF: reached root node\n");
 455                         result = of_read_number(addr, na);
 456                         break;
 457                 }
 458
 459                 /* Get new parent bus and counts */
 460                 pbus = of_match_bus(parent);
 461                 pbus->count_cells(dev, &pna, &pns);
 462                 if (!OF_CHECK_COUNTS(pna, pns)) {
 463                         printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
 464                                dev->full_name);
 465                         break;
 466                 }
 467
 468                 pr_debug("OF: parent bus is %s (na=%d, ns=%d) on %s\n",
 469                     pbus->name, pna, pns, parent->full_name);
 470
 471                 /* Apply bus translation */
 472                 if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
 473                         break;
 474
 475                 /* Complete the move up one level */
 476                 na = pna;
 477                 ns = pns;
 478                 bus = pbus;
 479
 480                 of_dump_addr("OF: one level translation:", addr, na);
 481         }
 482  bail:
 483         of_node_put(parent);
 484         of_node_put(dev);
 485
 486         return result;
 487 }
 488
 489 u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
 490 {
 491         return __of_translate_address(dev, in_addr, "ranges");
 492 }
 493 EXPORT_SYMBOL(of_translate_address);
 494
 495 u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
 496 {
 497         return __of_translate_address(dev, in_addr, "dma-ranges");
 498 }
 499 EXPORT_SYMBOL(of_translate_dma_address);
 500
 501 bool of_can_translate_address(struct device_node *dev)
 502 {
 503         struct device_node *parent;
 504         struct of_bus *bus;
 505         int na, ns;
 506
 507         parent = of_get_parent(dev);
 508         if (parent == NULL)
 509                 return false;
 510
 511         bus = of_match_bus(parent);
 512         bus->count_cells(dev, &na, &ns);
 513
 514         of_node_put(parent);
 515
 516         return OF_CHECK_COUNTS(na, ns);
 517 }
 518 EXPORT_SYMBOL(of_can_translate_address);
 519
 520 const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
 521                     unsigned int *flags)
 522 {
 523         const __be32 *prop;
 524         unsigned int psize;
 525         struct device_node *parent;
 526         struct of_bus *bus;
 527         int onesize, i, na, ns;
 528
 529         /* Get parent & match bus type */
 530         parent = of_get_parent(dev);
 531         if (parent == NULL)
 532                 return NULL;
 533         bus = of_match_bus(parent);
 534         bus->count_cells(dev, &na, &ns);
 535         of_node_put(parent);
 536         if (!OF_CHECK_ADDR_COUNT(na))
 537                 return NULL;
 538
 539         /* Get "reg" or "assigned-addresses" property */
 540         prop = of_get_property(dev, bus->addresses, &psize);
 541         if (prop == NULL)
 542                 return NULL;
 543         psize /= 4;
 544
 545         onesize = na + ns;
 546         for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
 547                 if (i == index) {
 548                         if (size)
 549                                 *size = of_read_number(prop + na, ns);
 550                         if (flags)
 551                                 *flags = bus->get_flags(prop);
 552                         return prop;
 553                 }
 554         return NULL;
 555 }
 556 EXPORT_SYMBOL(of_get_address);
 557
 558 static int __of_address_to_resource(struct device_node *dev,
 559                 const __be32 *addrp, u64 size, unsigned int flags,
 560                 const char *name, struct resource *r)
 561 {
 562         u64 taddr;
 563
 564         if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
 565                 return -EINVAL;
 566         taddr = of_translate_address(dev, addrp);
 567         if (taddr == OF_BAD_ADDR)
 568                 return -EINVAL;
 569         memset(r, 0, sizeof(struct resource));
 570         if (flags & IORESOURCE_IO) {
 571                 unsigned long port;
 572                 port = pci_address_to_pio(taddr);
 573                 if (port == (unsigned long)-1)
 574                         return -EINVAL;
 575                 r->start = port;
 576                 r->end = port + size - 1;
 577         } else {
 578                 r->start = taddr;
 579                 r->end = taddr + size - 1;
 580         }
 581         r->flags = flags;
 582         r->name = name ? name : dev->full_name;
 583
 584         return 0;
 585 }
 586
 587 /**
 588  * of_address_to_resource - Translate device tree address and return as resource
 589  *
 590  * Note that if your address is a PIO address, the conversion will fail if
 591  * the physical address can't be internally converted to an IO token with
 592  * pci_address_to_pio(), that is because it's either called to early or it
 593  * can't be matched to any host bridge IO space
 594  */
 595 int of_address_to_resource(struct device_node *dev, int index,
 596                            struct resource *r)
 597 {
 598         const __be32    *addrp;
 599         u64             size;
 600         unsigned int    flags;
 601         const char      *name = NULL;
 602
 603         addrp = of_get_address(dev, index, &size, &flags);
 604         if (addrp == NULL)
 605                 return -EINVAL;
 606
 607         /* Get optional "reg-names" property to add a name to a resource */
 608         of_property_read_string_index(dev, "reg-names", index, &name);
 609
 610         return __of_address_to_resource(dev, addrp, size, flags, name, r);
 611 }
 612 EXPORT_SYMBOL_GPL(of_address_to_resource);
 613
 614 struct device_node *of_find_matching_node_by_address(struct device_node *from,
 615                                         const struct of_device_id *matches,
 616                                         u64 base_address)
 617 {
 618         struct device_node *dn = of_find_matching_node(from, matches);
 619         struct resource res;
 620
 621         while (dn) {
 622                 if (of_address_to_resource(dn, 0, &res))
 623                         continue;
 624                 if (res.start == base_address)
 625                         return dn;
 626                 dn = of_find_matching_node(dn, matches);
 627         }
 628
 629         return NULL;
 630 }
 631
 632
 633 /**
 634  * of_iomap - Maps the memory mapped IO for a given device_node
 635  * @device:     the device whose io range will be mapped
 636  * @index:      index of the io range
 637  *
 638  * Returns a pointer to the mapped memory
 639  */
 640 void __iomem *of_iomap(struct device_node *np, int index)
 641 {
 642         struct resource res;
 643
 644         if (of_address_to_resource(np, index, &res))
 645                 return NULL;
 646
 647         return ioremap(res.start, resource_size(&res));
 648 }
 649 EXPORT_SYMBOL(of_iomap);