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