drivers/of/address.c

   1
   2 #include <linux/io.h>
   3 #include <linux/ioport.h>
   4 #include <linux/module.h>
   5 #include <linux/of_address.h>
   6 #include <linux/pci_regs.h>
   7 #include <linux/string.h>
   8
   9 /* Max address size we deal with */
  10 #define OF_MAX_ADDR_CELLS       4
  11 #define OF_CHECK_COUNTS(na, ns) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS && \
  12                         (ns) > 0)
  13
  14 static struct of_bus *of_match_bus(struct device_node *np);
  15 static int __of_address_to_resource(struct device_node *dev, const u32 *addrp,
  16                                     u64 size, unsigned int flags,
  17                                     struct resource *r);
  18
  19 /* Debug utility */
  20 #ifdef DEBUG
  21 static void of_dump_addr(const char *s, const u32 *addr, int na)
  22 {
  23         printk(KERN_DEBUG "%s", s);
  24         while (na--)
  25                 printk(" %08x", be32_to_cpu(*(addr++)));
  26         printk("\n");
  27 }
  28 #else
  29 static void of_dump_addr(const char *s, const u32 *addr, int na) { }
  30 #endif
  31
  32 /* Callbacks for bus specific translators */
  33 struct of_bus {
  34         const char      *name;
  35         const char      *addresses;
  36         int             (*match)(struct device_node *parent);
  37         void            (*count_cells)(struct device_node *child,
  38                                        int *addrc, int *sizec);
  39         u64             (*map)(u32 *addr, const u32 *range,
  40                                 int na, int ns, int pna);
  41         int             (*translate)(u32 *addr, u64 offset, int na);
  42         unsigned int    (*get_flags)(const u32 *addr);
  43 };
  44
  45 /*
  46  * Default translator (generic bus)
  47  */
  48
  49 static void of_bus_default_count_cells(struct device_node *dev,
  50                                        int *addrc, int *sizec)
  51 {
  52         if (addrc)
  53                 *addrc = of_n_addr_cells(dev);
  54         if (sizec)
  55                 *sizec = of_n_size_cells(dev);
  56 }
  57
  58 static u64 of_bus_default_map(u32 *addr, const u32 *range,
  59                 int na, int ns, int pna)
  60 {
  61         u64 cp, s, da;
  62
  63         cp = of_read_number(range, na);
  64         s  = of_read_number(range + na + pna, ns);
  65         da = of_read_number(addr, na);
  66
  67         pr_debug("OF: default map, cp=%llx, s=%llx, da=%llx\n",
  68                  (unsigned long long)cp, (unsigned long long)s,
  69                  (unsigned long long)da);
  70
  71         if (da < cp || da >= (cp + s))
  72                 return OF_BAD_ADDR;
  73         return da - cp;
  74 }
  75
  76 static int of_bus_default_translate(u32 *addr, u64 offset, int na)
  77 {
  78         u64 a = of_read_number(addr, na);
  79         memset(addr, 0, na * 4);
  80         a += offset;
  81         if (na > 1)
  82                 addr[na - 2] = cpu_to_be32(a >> 32);
  83         addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
  84
  85         return 0;
  86 }
  87
  88 static unsigned int of_bus_default_get_flags(const u32 *addr)
  89 {
  90         return IORESOURCE_MEM;
  91 }
  92
  93 #ifdef CONFIG_PCI
  94 /*
  95  * PCI bus specific translator
  96  */
  97
  98 static int of_bus_pci_match(struct device_node *np)
  99 {
 100         /* "vci" is for the /chaos bridge on 1st-gen PCI powermacs */
 101         return !strcmp(np->type, "pci") || !strcmp(np->type, "vci");
 102 }
 103
 104 static void of_bus_pci_count_cells(struct device_node *np,
 105                                    int *addrc, int *sizec)
 106 {
 107         if (addrc)
 108                 *addrc = 3;
 109         if (sizec)
 110                 *sizec = 2;
 111 }
 112
 113 static unsigned int of_bus_pci_get_flags(const u32 *addr)
 114 {
 115         unsigned int flags = 0;
 116         u32 w = addr[0];
 117
 118         switch((w >> 24) & 0x03) {
 119         case 0x01:
 120                 flags |= IORESOURCE_IO;
 121                 break;
 122         case 0x02: /* 32 bits */
 123         case 0x03: /* 64 bits */
 124                 flags |= IORESOURCE_MEM;
 125                 break;
 126         }
 127         if (w & 0x40000000)
 128                 flags |= IORESOURCE_PREFETCH;
 129         return flags;
 130 }
 131
 132 static u64 of_bus_pci_map(u32 *addr, const u32 *range, int na, int ns, int pna)
 133 {
 134         u64 cp, s, da;
 135         unsigned int af, rf;
 136
 137         af = of_bus_pci_get_flags(addr);
 138         rf = of_bus_pci_get_flags(range);
 139
 140         /* Check address type match */
 141         if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
 142                 return OF_BAD_ADDR;
 143
 144         /* Read address values, skipping high cell */
 145         cp = of_read_number(range + 1, na - 1);
 146         s  = of_read_number(range + na + pna, ns);
 147         da = of_read_number(addr + 1, na - 1);
 148
 149         pr_debug("OF: PCI map, cp=%llx, s=%llx, da=%llx\n",
 150                  (unsigned long long)cp, (unsigned long long)s,
 151                  (unsigned long long)da);
 152
 153         if (da < cp || da >= (cp + s))
 154                 return OF_BAD_ADDR;
 155         return da - cp;
 156 }
 157
 158 static int of_bus_pci_translate(u32 *addr, u64 offset, int na)
 159 {
 160         return of_bus_default_translate(addr + 1, offset, na - 1);
 161 }
 162
 163 const u32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
 164                         unsigned int *flags)
 165 {
 166         const __be32 *prop;
 167         unsigned int psize;
 168         struct device_node *parent;
 169         struct of_bus *bus;
 170         int onesize, i, na, ns;
 171
 172         /* Get parent & match bus type */
 173         parent = of_get_parent(dev);
 174         if (parent == NULL)
 175                 return NULL;
 176         bus = of_match_bus(parent);
 177         if (strcmp(bus->name, "pci")) {
 178                 of_node_put(parent);
 179                 return NULL;
 180         }
 181         bus->count_cells(dev, &na, &ns);
 182         of_node_put(parent);
 183         if (!OF_CHECK_COUNTS(na, ns))
 184                 return NULL;
 185
 186         /* Get "reg" or "assigned-addresses" property */
 187         prop = of_get_property(dev, bus->addresses, &psize);
 188         if (prop == NULL)
 189                 return NULL;
 190         psize /= 4;
 191
 192         onesize = na + ns;
 193         for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
 194                 u32 val = be32_to_cpu(prop[0]);
 195                 if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
 196                         if (size)
 197                                 *size = of_read_number(prop + na, ns);
 198                         if (flags)
 199                                 *flags = bus->get_flags(prop);
 200                         return prop;
 201                 }
 202         }
 203         return NULL;
 204 }
 205 EXPORT_SYMBOL(of_get_pci_address);
 206
 207 int of_pci_address_to_resource(struct device_node *dev, int bar,
 208                                struct resource *r)
 209 {
 210         const u32       *addrp;
 211         u64             size;
 212         unsigned int    flags;
 213
 214         addrp = of_get_pci_address(dev, bar, &size, &flags);
 215         if (addrp == NULL)
 216                 return -EINVAL;
 217         return __of_address_to_resource(dev, addrp, size, flags, r);
 218 }
 219 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
 220 #endif /* CONFIG_PCI */
 221
 222 /*
 223  * ISA bus specific translator
 224  */
 225
 226 static int of_bus_isa_match(struct device_node *np)
 227 {
 228         return !strcmp(np->name, "isa");
 229 }
 230
 231 static void of_bus_isa_count_cells(struct device_node *child,
 232                                    int *addrc, int *sizec)
 233 {
 234         if (addrc)
 235                 *addrc = 2;
 236         if (sizec)
 237                 *sizec = 1;
 238 }
 239
 240 static u64 of_bus_isa_map(u32 *addr, const u32 *range, int na, int ns, int pna)
 241 {
 242         u64 cp, s, da;
 243
 244         /* Check address type match */
 245         if ((addr[0] ^ range[0]) & 0x00000001)
 246                 return OF_BAD_ADDR;
 247
 248         /* Read address values, skipping high cell */
 249         cp = of_read_number(range + 1, na - 1);
 250         s  = of_read_number(range + na + pna, ns);
 251         da = of_read_number(addr + 1, na - 1);
 252
 253         pr_debug("OF: ISA map, cp=%llx, s=%llx, da=%llx\n",
 254                  (unsigned long long)cp, (unsigned long long)s,
 255                  (unsigned long long)da);
 256
 257         if (da < cp || da >= (cp + s))
 258                 return OF_BAD_ADDR;
 259         return da - cp;
 260 }
 261
 262 static int of_bus_isa_translate(u32 *addr, u64 offset, int na)
 263 {
 264         return of_bus_default_translate(addr + 1, offset, na - 1);
 265 }
 266
 267 static unsigned int of_bus_isa_get_flags(const u32 *addr)
 268 {
 269         unsigned int flags = 0;
 270         u32 w = addr[0];
 271
 272         if (w & 1)
 273                 flags |= IORESOURCE_IO;
 274         else
 275                 flags |= IORESOURCE_MEM;
 276         return flags;
 277 }
 278
 279 /*
 280  * Array of bus specific translators
 281  */
 282
 283 static struct of_bus of_busses[] = {
 284 #ifdef CONFIG_PCI
 285         /* PCI */
 286         {
 287                 .name = "pci",
 288                 .addresses = "assigned-addresses",
 289                 .match = of_bus_pci_match,
 290                 .count_cells = of_bus_pci_count_cells,
 291                 .map = of_bus_pci_map,
 292                 .translate = of_bus_pci_translate,
 293                 .get_flags = of_bus_pci_get_flags,
 294         },
 295 #endif /* CONFIG_PCI */
 296         /* ISA */
 297         {
 298                 .name = "isa",
 299                 .addresses = "reg",
 300                 .match = of_bus_isa_match,
 301                 .count_cells = of_bus_isa_count_cells,
 302                 .map = of_bus_isa_map,
 303                 .translate = of_bus_isa_translate,
 304                 .get_flags = of_bus_isa_get_flags,
 305         },
 306         /* Default */
 307         {
 308                 .name = "default",
 309                 .addresses = "reg",
 310                 .match = NULL,
 311                 .count_cells = of_bus_default_count_cells,
 312                 .map = of_bus_default_map,
 313                 .translate = of_bus_default_translate,
 314                 .get_flags = of_bus_default_get_flags,
 315         },
 316 };
 317
 318 static struct of_bus *of_match_bus(struct device_node *np)
 319 {
 320         int i;
 321
 322         for (i = 0; i < ARRAY_SIZE(of_busses); i++)
 323                 if (!of_busses[i].match || of_busses[i].match(np))
 324                         return &of_busses[i];
 325         BUG();
 326         return NULL;
 327 }
 328
 329 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
 330                             struct of_bus *pbus, u32 *addr,
 331                             int na, int ns, int pna, const char *rprop)
 332 {
 333         const u32 *ranges;
 334         unsigned int rlen;
 335         int rone;
 336         u64 offset = OF_BAD_ADDR;
 337
 338         /* Normally, an absence of a "ranges" property means we are
 339          * crossing a non-translatable boundary, and thus the addresses
 340          * below the current not cannot be converted to CPU physical ones.
 341          * Unfortunately, while this is very clear in the spec, it's not
 342          * what Apple understood, and they do have things like /uni-n or
 343          * /ht nodes with no "ranges" property and a lot of perfectly
 344          * useable mapped devices below them. Thus we treat the absence of
 345          * "ranges" as equivalent to an empty "ranges" property which means
 346          * a 1:1 translation at that level. It's up to the caller not to try
 347          * to translate addresses that aren't supposed to be translated in
 348          * the first place. --BenH.
 349          *
 350          * As far as we know, this damage only exists on Apple machines, so
 351          * This code is only enabled on powerpc. --gcl
 352          */
 353         ranges = of_get_property(parent, rprop, &rlen);
 354 #if !defined(CONFIG_PPC)
 355         if (ranges == NULL) {
 356                 pr_err("OF: no ranges; cannot translate\n");
 357                 return 1;
 358         }
 359 #endif /* !defined(CONFIG_PPC) */
 360         if (ranges == NULL || rlen == 0) {
 361                 offset = of_read_number(addr, na);
 362                 memset(addr, 0, pna * 4);
 363                 pr_debug("OF: empty ranges; 1:1 translation\n");
 364                 goto finish;
 365         }
 366
 367         pr_debug("OF: walking ranges...\n");
 368
 369         /* Now walk through the ranges */
 370         rlen /= 4;
 371         rone = na + pna + ns;
 372         for (; rlen >= rone; rlen -= rone, ranges += rone) {
 373                 offset = bus->map(addr, ranges, na, ns, pna);
 374                 if (offset != OF_BAD_ADDR)
 375                         break;
 376         }
 377         if (offset == OF_BAD_ADDR) {
 378                 pr_debug("OF: not found !\n");
 379                 return 1;
 380         }
 381         memcpy(addr, ranges + na, 4 * pna);
 382
 383  finish:
 384         of_dump_addr("OF: parent translation for:", addr, pna);
 385         pr_debug("OF: with offset: %llx\n", (unsigned long long)offset);
 386
 387         /* Translate it into parent bus space */
 388         return pbus->translate(addr, offset, pna);
 389 }
 390
 391 /*
 392  * Translate an address from the device-tree into a CPU physical address,
 393  * this walks up the tree and applies the various bus mappings on the
 394  * way.
 395  *
 396  * Note: We consider that crossing any level with #size-cells == 0 to mean
 397  * that translation is impossible (that is we are not dealing with a value
 398  * that can be mapped to a cpu physical address). This is not really specified
 399  * that way, but this is traditionally the way IBM at least do things
 400  */
 401 u64 __of_translate_address(struct device_node *dev, const u32 *in_addr,
 402                            const char *rprop)
 403 {
 404         struct device_node *parent = NULL;
 405         struct of_bus *bus, *pbus;
 406         u32 addr[OF_MAX_ADDR_CELLS];
 407         int na, ns, pna, pns;
 408         u64 result = OF_BAD_ADDR;
 409
 410         pr_debug("OF: ** translation for device %s **\n", dev->full_name);
 411
 412         /* Increase refcount at current level */
 413         of_node_get(dev);
 414
 415         /* Get parent & match bus type */
 416         parent = of_get_parent(dev);
 417         if (parent == NULL)
 418                 goto bail;
 419         bus = of_match_bus(parent);
 420
 421         /* Cound address cells & copy address locally */
 422         bus->count_cells(dev, &na, &ns);
 423         if (!OF_CHECK_COUNTS(na, ns)) {
 424                 printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
 425                        dev->full_name);
 426                 goto bail;
 427         }
 428         memcpy(addr, in_addr, na * 4);
 429
 430         pr_debug("OF: bus is %s (na=%d, ns=%d) on %s\n",
 431             bus->name, na, ns, parent->full_name);
 432         of_dump_addr("OF: translating address:", addr, na);
 433
 434         /* Translate */
 435         for (;;) {
 436                 /* Switch to parent bus */
 437                 of_node_put(dev);
 438                 dev = parent;
 439                 parent = of_get_parent(dev);
 440
 441                 /* If root, we have finished */
 442                 if (parent == NULL) {
 443                         pr_debug("OF: reached root node\n");
 444                         result = of_read_number(addr, na);
 445                         break;
 446                 }
 447
 448                 /* Get new parent bus and counts */
 449                 pbus = of_match_bus(parent);
 450                 pbus->count_cells(dev, &pna, &pns);
 451                 if (!OF_CHECK_COUNTS(pna, pns)) {
 452                         printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
 453                                dev->full_name);
 454                         break;
 455                 }
 456
 457                 pr_debug("OF: parent bus is %s (na=%d, ns=%d) on %s\n",
 458                     pbus->name, pna, pns, parent->full_name);
 459
 460                 /* Apply bus translation */
 461                 if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
 462                         break;
 463
 464                 /* Complete the move up one level */
 465                 na = pna;
 466                 ns = pns;
 467                 bus = pbus;
 468
 469                 of_dump_addr("OF: one level translation:", addr, na);
 470         }
 471  bail:
 472         of_node_put(parent);
 473         of_node_put(dev);
 474
 475         return result;
 476 }
 477
 478 u64 of_translate_address(struct device_node *dev, const u32 *in_addr)
 479 {
 480         return __of_translate_address(dev, in_addr, "ranges");
 481 }
 482 EXPORT_SYMBOL(of_translate_address);
 483
 484 u64 of_translate_dma_address(struct device_node *dev, const u32 *in_addr)
 485 {
 486         return __of_translate_address(dev, in_addr, "dma-ranges");
 487 }
 488 EXPORT_SYMBOL(of_translate_dma_address);
 489
 490 const u32 *of_get_address(struct device_node *dev, int index, u64 *size,
 491                     unsigned int *flags)
 492 {
 493         const u32 *prop;
 494         unsigned int psize;
 495         struct device_node *parent;
 496         struct of_bus *bus;
 497         int onesize, i, na, ns;
 498
 499         /* Get parent & match bus type */
 500         parent = of_get_parent(dev);
 501         if (parent == NULL)
 502                 return NULL;
 503         bus = of_match_bus(parent);
 504         bus->count_cells(dev, &na, &ns);
 505         of_node_put(parent);
 506         if (!OF_CHECK_COUNTS(na, ns))
 507                 return NULL;
 508
 509         /* Get "reg" or "assigned-addresses" property */
 510         prop = of_get_property(dev, bus->addresses, &psize);
 511         if (prop == NULL)
 512                 return NULL;
 513         psize /= 4;
 514
 515         onesize = na + ns;
 516         for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
 517                 if (i == index) {
 518                         if (size)
 519                                 *size = of_read_number(prop + na, ns);
 520                         if (flags)
 521                                 *flags = bus->get_flags(prop);
 522                         return prop;
 523                 }
 524         return NULL;
 525 }
 526 EXPORT_SYMBOL(of_get_address);
 527
 528 static int __of_address_to_resource(struct device_node *dev, const u32 *addrp,
 529                                     u64 size, unsigned int flags,
 530                                     struct resource *r)
 531 {
 532         u64 taddr;
 533
 534         if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
 535                 return -EINVAL;
 536         taddr = of_translate_address(dev, addrp);
 537         if (taddr == OF_BAD_ADDR)
 538                 return -EINVAL;
 539         memset(r, 0, sizeof(struct resource));
 540         if (flags & IORESOURCE_IO) {
 541                 unsigned long port;
 542                 port = pci_address_to_pio(taddr);
 543                 if (port == (unsigned long)-1)
 544                         return -EINVAL;
 545                 r->start = port;
 546                 r->end = port + size - 1;
 547         } else {
 548                 r->start = taddr;
 549                 r->end = taddr + size - 1;
 550         }
 551         r->flags = flags;
 552         r->name = dev->full_name;
 553         return 0;
 554 }
 555
 556 /**
 557  * of_address_to_resource - Translate device tree address and return as resource
 558  *
 559  * Note that if your address is a PIO address, the conversion will fail if
 560  * the physical address can't be internally converted to an IO token with
 561  * pci_address_to_pio(), that is because it's either called to early or it
 562  * can't be matched to any host bridge IO space
 563  */
 564 int of_address_to_resource(struct device_node *dev, int index,
 565                            struct resource *r)
 566 {
 567         const u32       *addrp;
 568         u64             size;
 569         unsigned int    flags;
 570
 571         addrp = of_get_address(dev, index, &size, &flags);
 572         if (addrp == NULL)
 573                 return -EINVAL;
 574         return __of_address_to_resource(dev, addrp, size, flags, r);
 575 }
 576 EXPORT_SYMBOL_GPL(of_address_to_resource);
 577
 578
 579 /**
 580  * of_iomap - Maps the memory mapped IO for a given device_node
 581  * @device:     the device whose io range will be mapped
 582  * @index:      index of the io range
 583  *
 584  * Returns a pointer to the mapped memory
 585  */
 586 void __iomem *of_iomap(struct device_node *np, int index)
 587 {
 588         struct resource res;
 589
 590         if (of_address_to_resource(np, index, &res))
 591                 return NULL;
 592
 593         return ioremap(res.start, 1 + res.end - res.start);
 594 }
 595 EXPORT_SYMBOL(of_iomap);