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