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