arch/powerpc/kernel/prom.c

   1 /*
   2  * Procedures for creating, accessing and interpreting the device tree.
   3  *
   4  * Paul Mackerras       August 1996.
   5  * Copyright (C) 1996-2005 Paul Mackerras.
   6  *
   7  *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
   8  *    {engebret|bergner}@us.ibm.com
   9  *
  10  *      This program is free software; you can redistribute it and/or
  11  *      modify it under the terms of the GNU General Public License
  12  *      as published by the Free Software Foundation; either version
  13  *      2 of the License, or (at your option) any later version.
  14  */
  15
  16 #undef DEBUG
  17
  18 #include <stdarg.h>
  19 #include <linux/kernel.h>
  20 #include <linux/string.h>
  21 #include <linux/init.h>
  22 #include <linux/threads.h>
  23 #include <linux/spinlock.h>
  24 #include <linux/types.h>
  25 #include <linux/pci.h>
  26 #include <linux/stringify.h>
  27 #include <linux/delay.h>
  28 #include <linux/initrd.h>
  29 #include <linux/bitops.h>
  30 #include <linux/module.h>
  31 #include <linux/kexec.h>
  32 #include <linux/debugfs.h>
  33 #include <linux/irq.h>
  34 #include <linux/lmb.h>
  35
  36 #include <asm/prom.h>
  37 #include <asm/rtas.h>
  38 #include <asm/page.h>
  39 #include <asm/processor.h>
  40 #include <asm/irq.h>
  41 #include <asm/io.h>
  42 #include <asm/kdump.h>
  43 #include <asm/smp.h>
  44 #include <asm/system.h>
  45 #include <asm/mmu.h>
  46 #include <asm/pgtable.h>
  47 #include <asm/pci.h>
  48 #include <asm/iommu.h>
  49 #include <asm/btext.h>
  50 #include <asm/sections.h>
  51 #include <asm/machdep.h>
  52 #include <asm/pSeries_reconfig.h>
  53 #include <asm/pci-bridge.h>
  54 #include <asm/phyp_dump.h>
  55 #include <asm/kexec.h>
  56 #include <mm/mmu_decl.h>
  57
  58 #ifdef DEBUG
  59 #define DBG(fmt...) printk(KERN_ERR fmt)
  60 #else
  61 #define DBG(fmt...)
  62 #endif
  63
  64
  65 static int __initdata dt_root_addr_cells;
  66 static int __initdata dt_root_size_cells;
  67
  68 #ifdef CONFIG_PPC64
  69 int __initdata iommu_is_off;
  70 int __initdata iommu_force_on;
  71 unsigned long tce_alloc_start, tce_alloc_end;
  72 #endif
  73
  74 typedef u32 cell_t;
  75
  76 #if 0
  77 static struct boot_param_header *initial_boot_params __initdata;
  78 #else
  79 struct boot_param_header *initial_boot_params;
  80 #endif
  81
  82 extern struct device_node *allnodes;    /* temporary while merging */
  83
  84 extern rwlock_t devtree_lock;   /* temporary while merging */
  85
  86 /* export that to outside world */
  87 struct device_node *of_chosen;
  88
  89 static inline char *find_flat_dt_string(u32 offset)
  90 {
  91         return ((char *)initial_boot_params) +
  92                 initial_boot_params->off_dt_strings + offset;
  93 }
  94
  95 /**
  96  * This function is used to scan the flattened device-tree, it is
  97  * used to extract the memory informations at boot before we can
  98  * unflatten the tree
  99  */
 100 int __init of_scan_flat_dt(int (*it)(unsigned long node,
 101                                      const char *uname, int depth,
 102                                      void *data),
 103                            void *data)
 104 {
 105         unsigned long p = ((unsigned long)initial_boot_params) +
 106                 initial_boot_params->off_dt_struct;
 107         int rc = 0;
 108         int depth = -1;
 109
 110         do {
 111                 u32 tag = *((u32 *)p);
 112                 char *pathp;
 113
 114                 p += 4;
 115                 if (tag == OF_DT_END_NODE) {
 116                         depth --;
 117                         continue;
 118                 }
 119                 if (tag == OF_DT_NOP)
 120                         continue;
 121                 if (tag == OF_DT_END)
 122                         break;
 123                 if (tag == OF_DT_PROP) {
 124                         u32 sz = *((u32 *)p);
 125                         p += 8;
 126                         if (initial_boot_params->version < 0x10)
 127                                 p = _ALIGN(p, sz >= 8 ? 8 : 4);
 128                         p += sz;
 129                         p = _ALIGN(p, 4);
 130                         continue;
 131                 }
 132                 if (tag != OF_DT_BEGIN_NODE) {
 133                         printk(KERN_WARNING "Invalid tag %x scanning flattened"
 134                                " device tree !\n", tag);
 135                         return -EINVAL;
 136                 }
 137                 depth++;
 138                 pathp = (char *)p;
 139                 p = _ALIGN(p + strlen(pathp) + 1, 4);
 140                 if ((*pathp) == '/') {
 141                         char *lp, *np;
 142                         for (lp = NULL, np = pathp; *np; np++)
 143                                 if ((*np) == '/')
 144                                         lp = np+1;
 145                         if (lp != NULL)
 146                                 pathp = lp;
 147                 }
 148                 rc = it(p, pathp, depth, data);
 149                 if (rc != 0)
 150                         break;
 151         } while(1);
 152
 153         return rc;
 154 }
 155
 156 unsigned long __init of_get_flat_dt_root(void)
 157 {
 158         unsigned long p = ((unsigned long)initial_boot_params) +
 159                 initial_boot_params->off_dt_struct;
 160
 161         while(*((u32 *)p) == OF_DT_NOP)
 162                 p += 4;
 163         BUG_ON (*((u32 *)p) != OF_DT_BEGIN_NODE);
 164         p += 4;
 165         return _ALIGN(p + strlen((char *)p) + 1, 4);
 166 }
 167
 168 /**
 169  * This  function can be used within scan_flattened_dt callback to get
 170  * access to properties
 171  */
 172 void* __init of_get_flat_dt_prop(unsigned long node, const char *name,
 173                                  unsigned long *size)
 174 {
 175         unsigned long p = node;
 176
 177         do {
 178                 u32 tag = *((u32 *)p);
 179                 u32 sz, noff;
 180                 const char *nstr;
 181
 182                 p += 4;
 183                 if (tag == OF_DT_NOP)
 184                         continue;
 185                 if (tag != OF_DT_PROP)
 186                         return NULL;
 187
 188                 sz = *((u32 *)p);
 189                 noff = *((u32 *)(p + 4));
 190                 p += 8;
 191                 if (initial_boot_params->version < 0x10)
 192                         p = _ALIGN(p, sz >= 8 ? 8 : 4);
 193
 194                 nstr = find_flat_dt_string(noff);
 195                 if (nstr == NULL) {
 196                         printk(KERN_WARNING "Can't find property index"
 197                                " name !\n");
 198                         return NULL;
 199                 }
 200                 if (strcmp(name, nstr) == 0) {
 201                         if (size)
 202                                 *size = sz;
 203                         return (void *)p;
 204                 }
 205                 p += sz;
 206                 p = _ALIGN(p, 4);
 207         } while(1);
 208 }
 209
 210 int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
 211 {
 212         const char* cp;
 213         unsigned long cplen, l;
 214
 215         cp = of_get_flat_dt_prop(node, "compatible", &cplen);
 216         if (cp == NULL)
 217                 return 0;
 218         while (cplen > 0) {
 219                 if (strncasecmp(cp, compat, strlen(compat)) == 0)
 220                         return 1;
 221                 l = strlen(cp) + 1;
 222                 cp += l;
 223                 cplen -= l;
 224         }
 225
 226         return 0;
 227 }
 228
 229 static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned long size,
 230                                        unsigned long align)
 231 {
 232         void *res;
 233
 234         *mem = _ALIGN(*mem, align);
 235         res = (void *)*mem;
 236         *mem += size;
 237
 238         return res;
 239 }
 240
 241 static unsigned long __init unflatten_dt_node(unsigned long mem,
 242                                               unsigned long *p,
 243                                               struct device_node *dad,
 244                                               struct device_node ***allnextpp,
 245                                               unsigned long fpsize)
 246 {
 247         struct device_node *np;
 248         struct property *pp, **prev_pp = NULL;
 249         char *pathp;
 250         u32 tag;
 251         unsigned int l, allocl;
 252         int has_name = 0;
 253         int new_format = 0;
 254
 255         tag = *((u32 *)(*p));
 256         if (tag != OF_DT_BEGIN_NODE) {
 257                 printk("Weird tag at start of node: %x\n", tag);
 258                 return mem;
 259         }
 260         *p += 4;
 261         pathp = (char *)*p;
 262         l = allocl = strlen(pathp) + 1;
 263         *p = _ALIGN(*p + l, 4);
 264
 265         /* version 0x10 has a more compact unit name here instead of the full
 266          * path. we accumulate the full path size using "fpsize", we'll rebuild
 267          * it later. We detect this because the first character of the name is
 268          * not '/'.
 269          */
 270         if ((*pathp) != '/') {
 271                 new_format = 1;
 272                 if (fpsize == 0) {
 273                         /* root node: special case. fpsize accounts for path
 274                          * plus terminating zero. root node only has '/', so
 275                          * fpsize should be 2, but we want to avoid the first
 276                          * level nodes to have two '/' so we use fpsize 1 here
 277                          */
 278                         fpsize = 1;
 279                         allocl = 2;
 280                 } else {
 281                         /* account for '/' and path size minus terminal 0
 282                          * already in 'l'
 283                          */
 284                         fpsize += l;
 285                         allocl = fpsize;
 286                 }
 287         }
 288
 289
 290         np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
 291                                 __alignof__(struct device_node));
 292         if (allnextpp) {
 293                 memset(np, 0, sizeof(*np));
 294                 np->full_name = ((char*)np) + sizeof(struct device_node);
 295                 if (new_format) {
 296                         char *p = np->full_name;
 297                         /* rebuild full path for new format */
 298                         if (dad && dad->parent) {
 299                                 strcpy(p, dad->full_name);
 300 #ifdef DEBUG
 301                                 if ((strlen(p) + l + 1) != allocl) {
 302                                         DBG("%s: p: %d, l: %d, a: %d\n",
 303                                             pathp, (int)strlen(p), l, allocl);
 304                                 }
 305 #endif
 306                                 p += strlen(p);
 307                         }
 308                         *(p++) = '/';
 309                         memcpy(p, pathp, l);
 310                 } else
 311                         memcpy(np->full_name, pathp, l);
 312                 prev_pp = &np->properties;
 313                 **allnextpp = np;
 314                 *allnextpp = &np->allnext;
 315                 if (dad != NULL) {
 316                         np->parent = dad;
 317                         /* we temporarily use the next field as `last_child'*/
 318                         if (dad->next == 0)
 319                                 dad->child = np;
 320                         else
 321                                 dad->next->sibling = np;
 322                         dad->next = np;
 323                 }
 324                 kref_init(&np->kref);
 325         }
 326         while(1) {
 327                 u32 sz, noff;
 328                 char *pname;
 329
 330                 tag = *((u32 *)(*p));
 331                 if (tag == OF_DT_NOP) {
 332                         *p += 4;
 333                         continue;
 334                 }
 335                 if (tag != OF_DT_PROP)
 336                         break;
 337                 *p += 4;
 338                 sz = *((u32 *)(*p));
 339                 noff = *((u32 *)((*p) + 4));
 340                 *p += 8;
 341                 if (initial_boot_params->version < 0x10)
 342                         *p = _ALIGN(*p, sz >= 8 ? 8 : 4);
 343
 344                 pname = find_flat_dt_string(noff);
 345                 if (pname == NULL) {
 346                         printk("Can't find property name in list !\n");
 347                         break;
 348                 }
 349                 if (strcmp(pname, "name") == 0)
 350                         has_name = 1;
 351                 l = strlen(pname) + 1;
 352                 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
 353                                         __alignof__(struct property));
 354                 if (allnextpp) {
 355                         if (strcmp(pname, "linux,phandle") == 0) {
 356                                 np->node = *((u32 *)*p);
 357                                 if (np->linux_phandle == 0)
 358                                         np->linux_phandle = np->node;
 359                         }
 360                         if (strcmp(pname, "ibm,phandle") == 0)
 361                                 np->linux_phandle = *((u32 *)*p);
 362                         pp->name = pname;
 363                         pp->length = sz;
 364                         pp->value = (void *)*p;
 365                         *prev_pp = pp;
 366                         prev_pp = &pp->next;
 367                 }
 368                 *p = _ALIGN((*p) + sz, 4);
 369         }
 370         /* with version 0x10 we may not have the name property, recreate
 371          * it here from the unit name if absent
 372          */
 373         if (!has_name) {
 374                 char *p = pathp, *ps = pathp, *pa = NULL;
 375                 int sz;
 376
 377                 while (*p) {
 378                         if ((*p) == '@')
 379                                 pa = p;
 380                         if ((*p) == '/')
 381                                 ps = p + 1;
 382                         p++;
 383                 }
 384                 if (pa < ps)
 385                         pa = p;
 386                 sz = (pa - ps) + 1;
 387                 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
 388                                         __alignof__(struct property));
 389                 if (allnextpp) {
 390                         pp->name = "name";
 391                         pp->length = sz;
 392                         pp->value = pp + 1;
 393                         *prev_pp = pp;
 394                         prev_pp = &pp->next;
 395                         memcpy(pp->value, ps, sz - 1);
 396                         ((char *)pp->value)[sz - 1] = 0;
 397                         DBG("fixed up name for %s -> %s\n", pathp,
 398                                 (char *)pp->value);
 399                 }
 400         }
 401         if (allnextpp) {
 402                 *prev_pp = NULL;
 403                 np->name = of_get_property(np, "name", NULL);
 404                 np->type = of_get_property(np, "device_type", NULL);
 405
 406                 if (!np->name)
 407                         np->name = "<NULL>";
 408                 if (!np->type)
 409                         np->type = "<NULL>";
 410         }
 411         while (tag == OF_DT_BEGIN_NODE) {
 412                 mem = unflatten_dt_node(mem, p, np, allnextpp, fpsize);
 413                 tag = *((u32 *)(*p));
 414         }
 415         if (tag != OF_DT_END_NODE) {
 416                 printk("Weird tag at end of node: %x\n", tag);
 417                 return mem;
 418         }
 419         *p += 4;
 420         return mem;
 421 }
 422
 423 static int __init early_parse_mem(char *p)
 424 {
 425         if (!p)
 426                 return 1;
 427
 428         memory_limit = PAGE_ALIGN(memparse(p, &p));
 429         DBG("memory limit = 0x%lx\n", memory_limit);
 430
 431         return 0;
 432 }
 433 early_param("mem", early_parse_mem);
 434
 435 /**
 436  * move_device_tree - move tree to an unused area, if needed.
 437  *
 438  * The device tree may be allocated beyond our memory limit, or inside the
 439  * crash kernel region for kdump. If so, move it out of the way.
 440  */
 441 static void __init move_device_tree(void)
 442 {
 443         unsigned long start, size;
 444         void *p;
 445
 446         DBG("-> move_device_tree\n");
 447
 448         start = __pa(initial_boot_params);
 449         size = initial_boot_params->totalsize;
 450
 451         if ((memory_limit && (start + size) > memory_limit) ||
 452                         overlaps_crashkernel(start, size)) {
 453                 p = __va(lmb_alloc_base(size, PAGE_SIZE, lmb.rmo_size));
 454                 memcpy(p, initial_boot_params, size);
 455                 initial_boot_params = (struct boot_param_header *)p;
 456                 DBG("Moved device tree to 0x%p\n", p);
 457         }
 458
 459         DBG("<- move_device_tree\n");
 460 }
 461
 462 /**
 463  * unflattens the device-tree passed by the firmware, creating the
 464  * tree of struct device_node. It also fills the "name" and "type"
 465  * pointers of the nodes so the normal device-tree walking functions
 466  * can be used (this used to be done by finish_device_tree)
 467  */
 468 void __init unflatten_device_tree(void)
 469 {
 470         unsigned long start, mem, size;
 471         struct device_node **allnextp = &allnodes;
 472
 473         DBG(" -> unflatten_device_tree()\n");
 474
 475         /* First pass, scan for size */
 476         start = ((unsigned long)initial_boot_params) +
 477                 initial_boot_params->off_dt_struct;
 478         size = unflatten_dt_node(0, &start, NULL, NULL, 0);
 479         size = (size | 3) + 1;
 480
 481         DBG("  size is %lx, allocating...\n", size);
 482
 483         /* Allocate memory for the expanded device tree */
 484         mem = lmb_alloc(size + 4, __alignof__(struct device_node));
 485         mem = (unsigned long) __va(mem);
 486
 487         ((u32 *)mem)[size / 4] = 0xdeadbeef;
 488
 489         DBG("  unflattening %lx...\n", mem);
 490
 491         /* Second pass, do actual unflattening */
 492         start = ((unsigned long)initial_boot_params) +
 493                 initial_boot_params->off_dt_struct;
 494         unflatten_dt_node(mem, &start, NULL, &allnextp, 0);
 495         if (*((u32 *)start) != OF_DT_END)
 496                 printk(KERN_WARNING "Weird tag at end of tree: %08x\n", *((u32 *)start));
 497         if (((u32 *)mem)[size / 4] != 0xdeadbeef)
 498                 printk(KERN_WARNING "End of tree marker overwritten: %08x\n",
 499                        ((u32 *)mem)[size / 4] );
 500         *allnextp = NULL;
 501
 502         /* Get pointer to OF "/chosen" node for use everywhere */
 503         of_chosen = of_find_node_by_path("/chosen");
 504         if (of_chosen == NULL)
 505                 of_chosen = of_find_node_by_path("/chosen@0");
 506
 507         DBG(" <- unflatten_device_tree()\n");
 508 }
 509
 510 /*
 511  * ibm,pa-features is a per-cpu property that contains a string of
 512  * attribute descriptors, each of which has a 2 byte header plus up
 513  * to 254 bytes worth of processor attribute bits.  First header
 514  * byte specifies the number of bytes following the header.
 515  * Second header byte is an "attribute-specifier" type, of which
 516  * zero is the only currently-defined value.
 517  * Implementation:  Pass in the byte and bit offset for the feature
 518  * that we are interested in.  The function will return -1 if the
 519  * pa-features property is missing, or a 1/0 to indicate if the feature
 520  * is supported/not supported.  Note that the bit numbers are
 521  * big-endian to match the definition in PAPR.
 522  */
 523 static struct ibm_pa_feature {
 524         unsigned long   cpu_features;   /* CPU_FTR_xxx bit */
 525         unsigned int    cpu_user_ftrs;  /* PPC_FEATURE_xxx bit */
 526         unsigned char   pabyte;         /* byte number in ibm,pa-features */
 527         unsigned char   pabit;          /* bit number (big-endian) */
 528         unsigned char   invert;         /* if 1, pa bit set => clear feature */
 529 } ibm_pa_features[] __initdata = {
 530         {0, PPC_FEATURE_HAS_MMU,        0, 0, 0},
 531         {0, PPC_FEATURE_HAS_FPU,        0, 1, 0},
 532         {CPU_FTR_SLB, 0,                0, 2, 0},
 533         {CPU_FTR_CTRL, 0,               0, 3, 0},
 534         {CPU_FTR_NOEXECUTE, 0,          0, 6, 0},
 535         {CPU_FTR_NODSISRALIGN, 0,       1, 1, 1},
 536         {CPU_FTR_CI_LARGE_PAGE, 0,      1, 2, 0},
 537         {CPU_FTR_REAL_LE, PPC_FEATURE_TRUE_LE, 5, 0, 0},
 538 };
 539
 540 static void __init scan_features(unsigned long node, unsigned char *ftrs,
 541                                  unsigned long tablelen,
 542                                  struct ibm_pa_feature *fp,
 543                                  unsigned long ft_size)
 544 {
 545         unsigned long i, len, bit;
 546
 547         /* find descriptor with type == 0 */
 548         for (;;) {
 549                 if (tablelen < 3)
 550                         return;
 551                 len = 2 + ftrs[0];
 552                 if (tablelen < len)
 553                         return;         /* descriptor 0 not found */
 554                 if (ftrs[1] == 0)
 555                         break;
 556                 tablelen -= len;
 557                 ftrs += len;
 558         }
 559
 560         /* loop over bits we know about */
 561         for (i = 0; i < ft_size; ++i, ++fp) {
 562                 if (fp->pabyte >= ftrs[0])
 563                         continue;
 564                 bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
 565                 if (bit ^ fp->invert) {
 566                         cur_cpu_spec->cpu_features |= fp->cpu_features;
 567                         cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
 568                 } else {
 569                         cur_cpu_spec->cpu_features &= ~fp->cpu_features;
 570                         cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
 571                 }
 572         }
 573 }
 574
 575 static void __init check_cpu_pa_features(unsigned long node)
 576 {
 577         unsigned char *pa_ftrs;
 578         unsigned long tablelen;
 579
 580         pa_ftrs = of_get_flat_dt_prop(node, "ibm,pa-features", &tablelen);
 581         if (pa_ftrs == NULL)
 582                 return;
 583
 584         scan_features(node, pa_ftrs, tablelen,
 585                       ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
 586 }
 587
 588 #ifdef CONFIG_PPC64
 589 static void __init check_cpu_slb_size(unsigned long node)
 590 {
 591         u32 *slb_size_ptr;
 592
 593         slb_size_ptr = of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
 594         if (slb_size_ptr != NULL) {
 595                 mmu_slb_size = *slb_size_ptr;
 596         }
 597 }
 598 #else
 599 #define check_cpu_slb_size(node) do { } while(0)
 600 #endif
 601
 602 static struct feature_property {
 603         const char *name;
 604         u32 min_value;
 605         unsigned long cpu_feature;
 606         unsigned long cpu_user_ftr;
 607 } feature_properties[] __initdata = {
 608 #ifdef CONFIG_ALTIVEC
 609         {"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
 610         {"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
 611 #endif /* CONFIG_ALTIVEC */
 612 #ifdef CONFIG_VSX
 613         /* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
 614         {"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
 615 #endif /* CONFIG_VSX */
 616 #ifdef CONFIG_PPC64
 617         {"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
 618         {"ibm,purr", 1, CPU_FTR_PURR, 0},
 619         {"ibm,spurr", 1, CPU_FTR_SPURR, 0},
 620 #endif /* CONFIG_PPC64 */
 621 };
 622
 623 #if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
 624 static inline void identical_pvr_fixup(unsigned long node)
 625 {
 626         unsigned int pvr;
 627         char *model = of_get_flat_dt_prop(node, "model", NULL);
 628
 629         /*
 630          * Since 440GR(x)/440EP(x) processors have the same pvr,
 631          * we check the node path and set bit 28 in the cur_cpu_spec
 632          * pvr for EP(x) processor version. This bit is always 0 in
 633          * the "real" pvr. Then we call identify_cpu again with
 634          * the new logical pvr to enable FPU support.
 635          */
 636         if (model && strstr(model, "440EP")) {
 637                 pvr = cur_cpu_spec->pvr_value | 0x8;
 638                 identify_cpu(0, pvr);
 639                 DBG("Using logical pvr %x for %s\n", pvr, model);
 640         }
 641 }
 642 #else
 643 #define identical_pvr_fixup(node) do { } while(0)
 644 #endif
 645
 646 static void __init check_cpu_feature_properties(unsigned long node)
 647 {
 648         unsigned long i;
 649         struct feature_property *fp = feature_properties;
 650         const u32 *prop;
 651
 652         for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
 653                 prop = of_get_flat_dt_prop(node, fp->name, NULL);
 654                 if (prop && *prop >= fp->min_value) {
 655                         cur_cpu_spec->cpu_features |= fp->cpu_feature;
 656                         cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
 657                 }
 658         }
 659 }
 660
 661 static int __init early_init_dt_scan_cpus(unsigned long node,
 662                                           const char *uname, int depth,
 663                                           void *data)
 664 {
 665         static int logical_cpuid = 0;
 666         char *type = of_get_flat_dt_prop(node, "device_type", NULL);
 667         const u32 *prop;
 668         const u32 *intserv;
 669         int i, nthreads;
 670         unsigned long len;
 671         int found = 0;
 672
 673         /* We are scanning "cpu" nodes only */
 674         if (type == NULL || strcmp(type, "cpu") != 0)
 675                 return 0;
 676
 677         /* Get physical cpuid */
 678         intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
 679         if (intserv) {
 680                 nthreads = len / sizeof(int);
 681         } else {
 682                 intserv = of_get_flat_dt_prop(node, "reg", NULL);
 683                 nthreads = 1;
 684         }
 685
 686         /*
 687          * Now see if any of these threads match our boot cpu.
 688          * NOTE: This must match the parsing done in smp_setup_cpu_maps.
 689          */
 690         for (i = 0; i < nthreads; i++) {
 691                 /*
 692                  * version 2 of the kexec param format adds the phys cpuid of
 693                  * booted proc.
 694                  */
 695                 if (initial_boot_params && initial_boot_params->version >= 2) {
 696                         if (intserv[i] ==
 697                                         initial_boot_params->boot_cpuid_phys) {
 698                                 found = 1;
 699                                 break;
 700                         }
 701                 } else {
 702                         /*
 703                          * Check if it's the boot-cpu, set it's hw index now,
 704                          * unfortunately this format did not support booting
 705                          * off secondary threads.
 706                          */
 707                         if (of_get_flat_dt_prop(node,
 708                                         "linux,boot-cpu", NULL) != NULL) {
 709                                 found = 1;
 710                                 break;
 711                         }
 712                 }
 713
 714 #ifdef CONFIG_SMP
 715                 /* logical cpu id is always 0 on UP kernels */
 716                 logical_cpuid++;
 717 #endif
 718         }
 719
 720         if (found) {
 721                 DBG("boot cpu: logical %d physical %d\n", logical_cpuid,
 722                         intserv[i]);
 723                 boot_cpuid = logical_cpuid;
 724                 set_hard_smp_processor_id(boot_cpuid, intserv[i]);
 725
 726                 /*
 727                  * PAPR defines "logical" PVR values for cpus that
 728                  * meet various levels of the architecture:
 729                  * 0x0f000001   Architecture version 2.04
 730                  * 0x0f000002   Architecture version 2.05
 731                  * If the cpu-version property in the cpu node contains
 732                  * such a value, we call identify_cpu again with the
 733                  * logical PVR value in order to use the cpu feature
 734                  * bits appropriate for the architecture level.
 735                  *
 736                  * A POWER6 partition in "POWER6 architected" mode
 737                  * uses the 0x0f000002 PVR value; in POWER5+ mode
 738                  * it uses 0x0f000001.
 739                  */
 740                 prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
 741                 if (prop && (*prop & 0xff000000) == 0x0f000000)
 742                         identify_cpu(0, *prop);
 743
 744                 identical_pvr_fixup(node);
 745         }
 746
 747         check_cpu_feature_properties(node);
 748         check_cpu_pa_features(node);
 749         check_cpu_slb_size(node);
 750
 751 #ifdef CONFIG_PPC_PSERIES
 752         if (nthreads > 1)
 753                 cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
 754         else
 755                 cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
 756 #endif
 757
 758         return 0;
 759 }
 760
 761 #ifdef CONFIG_BLK_DEV_INITRD
 762 static void __init early_init_dt_check_for_initrd(unsigned long node)
 763 {
 764         unsigned long l;
 765         u32 *prop;
 766
 767         DBG("Looking for initrd properties... ");
 768
 769         prop = of_get_flat_dt_prop(node, "linux,initrd-start", &l);
 770         if (prop) {
 771                 initrd_start = (unsigned long)__va(of_read_ulong(prop, l/4));
 772
 773                 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l);
 774                 if (prop) {
 775                         initrd_end = (unsigned long)
 776                                         __va(of_read_ulong(prop, l/4));
 777                         initrd_below_start_ok = 1;
 778                 } else {
 779                         initrd_start = 0;
 780                 }
 781         }
 782
 783         DBG("initrd_start=0x%lx  initrd_end=0x%lx\n", initrd_start, initrd_end);
 784 }
 785 #else
 786 static inline void early_init_dt_check_for_initrd(unsigned long node)
 787 {
 788 }
 789 #endif /* CONFIG_BLK_DEV_INITRD */
 790
 791 static int __init early_init_dt_scan_chosen(unsigned long node,
 792                                             const char *uname, int depth, void *data)
 793 {
 794         unsigned long *lprop;
 795         unsigned long l;
 796         char *p;
 797
 798         DBG("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
 799
 800         if (depth != 1 ||
 801             (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
 802                 return 0;
 803
 804 #ifdef CONFIG_PPC64
 805         /* check if iommu is forced on or off */
 806         if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
 807                 iommu_is_off = 1;
 808         if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
 809                 iommu_force_on = 1;
 810 #endif
 811
 812         /* mem=x on the command line is the preferred mechanism */
 813         lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
 814         if (lprop)
 815                 memory_limit = *lprop;
 816
 817 #ifdef CONFIG_PPC64
 818         lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
 819         if (lprop)
 820                 tce_alloc_start = *lprop;
 821         lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
 822         if (lprop)
 823                 tce_alloc_end = *lprop;
 824 #endif
 825
 826 #ifdef CONFIG_KEXEC
 827         lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
 828         if (lprop)
 829                 crashk_res.start = *lprop;
 830
 831         lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
 832         if (lprop)
 833                 crashk_res.end = crashk_res.start + *lprop - 1;
 834 #endif
 835
 836         early_init_dt_check_for_initrd(node);
 837
 838         /* Retreive command line */
 839         p = of_get_flat_dt_prop(node, "bootargs", &l);
 840         if (p != NULL && l > 0)
 841                 strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));
 842
 843 #ifdef CONFIG_CMDLINE
 844         if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
 845                 strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
 846 #endif /* CONFIG_CMDLINE */
 847
 848         DBG("Command line is: %s\n", cmd_line);
 849
 850         /* break now */
 851         return 1;
 852 }
 853
 854 static int __init early_init_dt_scan_root(unsigned long node,
 855                                           const char *uname, int depth, void *data)
 856 {
 857         u32 *prop;
 858
 859         if (depth != 0)
 860                 return 0;
 861
 862         prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
 863         dt_root_size_cells = (prop == NULL) ? 1 : *prop;
 864         DBG("dt_root_size_cells = %x\n", dt_root_size_cells);
 865
 866         prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
 867         dt_root_addr_cells = (prop == NULL) ? 2 : *prop;
 868         DBG("dt_root_addr_cells = %x\n", dt_root_addr_cells);
 869
 870         /* break now */
 871         return 1;
 872 }
 873
 874 static u64 __init dt_mem_next_cell(int s, cell_t **cellp)
 875 {
 876         cell_t *p = *cellp;
 877
 878         *cellp = p + s;
 879         return of_read_number(p, s);
 880 }
 881
 882 #ifdef CONFIG_PPC_PSERIES
 883 /*
 884  * Interpret the ibm,dynamic-memory property in the
 885  * /ibm,dynamic-reconfiguration-memory node.
 886  * This contains a list of memory blocks along with NUMA affinity
 887  * information.
 888  */
 889 static int __init early_init_dt_scan_drconf_memory(unsigned long node)
 890 {
 891         cell_t *dm, *ls, *usm;
 892         unsigned long l, n, flags;
 893         u64 base, size, lmb_size;
 894         unsigned int is_kexec_kdump = 0, rngs;
 895
 896         ls = (cell_t *)of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
 897         if (ls == NULL || l < dt_root_size_cells * sizeof(cell_t))
 898                 return 0;
 899         lmb_size = dt_mem_next_cell(dt_root_size_cells, &ls);
 900
 901         dm = (cell_t *)of_get_flat_dt_prop(node, "ibm,dynamic-memory", &l);
 902         if (dm == NULL || l < sizeof(cell_t))
 903                 return 0;
 904
 905         n = *dm++;      /* number of entries */
 906         if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(cell_t))
 907                 return 0;
 908
 909         /* check if this is a kexec/kdump kernel. */
 910         usm = (cell_t *)of_get_flat_dt_prop(node, "linux,drconf-usable-memory",
 911                                                  &l);
 912         if (usm != NULL)
 913                 is_kexec_kdump = 1;
 914
 915         for (; n != 0; --n) {
 916                 base = dt_mem_next_cell(dt_root_addr_cells, &dm);
 917                 flags = dm[3];
 918                 /* skip DRC index, pad, assoc. list index, flags */
 919                 dm += 4;
 920                 /* skip this block if the reserved bit is set in flags (0x80)
 921                    or if the block is not assigned to this partition (0x8) */
 922                 if ((flags & 0x80) || !(flags & 0x8))
 923                         continue;
 924                 size = lmb_size;
 925                 rngs = 1;
 926                 if (is_kexec_kdump) {
 927                         /*
 928                          * For each lmb in ibm,dynamic-memory, a corresponding
 929                          * entry in linux,drconf-usable-memory property contains
 930                          * a counter 'p' followed by 'p' (base, size) duple.
 931                          * Now read the counter from
 932                          * linux,drconf-usable-memory property
 933                          */
 934                         rngs = dt_mem_next_cell(dt_root_size_cells, &usm);
 935                         if (!rngs) /* there are no (base, size) duple */
 936                                 continue;
 937                 }
 938                 do {
 939                         if (is_kexec_kdump) {
 940                                 base = dt_mem_next_cell(dt_root_addr_cells,
 941                                                          &usm);
 942                                 size = dt_mem_next_cell(dt_root_size_cells,
 943                                                          &usm);
 944                         }
 945                         if (iommu_is_off) {
 946                                 if (base >= 0x80000000ul)
 947                                         continue;
 948                                 if ((base + size) > 0x80000000ul)
 949                                         size = 0x80000000ul - base;
 950                         }
 951                         lmb_add(base, size);
 952                 } while (--rngs);
 953         }
 954         lmb_dump_all();
 955         return 0;
 956 }
 957 #else
 958 #define early_init_dt_scan_drconf_memory(node)  0
 959 #endif /* CONFIG_PPC_PSERIES */
 960
 961 static int __init early_init_dt_scan_memory(unsigned long node,
 962                                             const char *uname, int depth, void *data)
 963 {
 964         char *type = of_get_flat_dt_prop(node, "device_type", NULL);
 965         cell_t *reg, *endp;
 966         unsigned long l;
 967
 968         /* Look for the ibm,dynamic-reconfiguration-memory node */
 969         if (depth == 1 &&
 970             strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
 971                 return early_init_dt_scan_drconf_memory(node);
 972
 973         /* We are scanning "memory" nodes only */
 974         if (type == NULL) {
 975                 /*
 976                  * The longtrail doesn't have a device_type on the
 977                  * /memory node, so look for the node called /memory@0.
 978                  */
 979                 if (depth != 1 || strcmp(uname, "memory@0") != 0)
 980                         return 0;
 981         } else if (strcmp(type, "memory") != 0)
 982                 return 0;
 983
 984         reg = (cell_t *)of_get_flat_dt_prop(node, "linux,usable-memory", &l);
 985         if (reg == NULL)
 986                 reg = (cell_t *)of_get_flat_dt_prop(node, "reg", &l);
 987         if (reg == NULL)
 988                 return 0;
 989
 990         endp = reg + (l / sizeof(cell_t));
 991
 992         DBG("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
 993             uname, l, reg[0], reg[1], reg[2], reg[3]);
 994
 995         while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
 996                 u64 base, size;
 997
 998                 base = dt_mem_next_cell(dt_root_addr_cells, &reg);
 999                 size = dt_mem_next_cell(dt_root_size_cells, &reg);
1000
1001                 if (size == 0)
1002                         continue;
1003                 DBG(" - %llx ,  %llx\n", (unsigned long long)base,
1004                     (unsigned long long)size);
1005 #ifdef CONFIG_PPC64
1006                 if (iommu_is_off) {
1007                         if (base >= 0x80000000ul)
1008                                 continue;
1009                         if ((base + size) > 0x80000000ul)
1010                                 size = 0x80000000ul - base;
1011                 }
1012 #endif
1013                 lmb_add(base, size);
1014
1015                 memstart_addr = min((u64)memstart_addr, base);
1016         }
1017
1018         return 0;
1019 }
1020
1021 static void __init early_reserve_mem(void)
1022 {
1023         u64 base, size;
1024         u64 *reserve_map;
1025         unsigned long self_base;
1026         unsigned long self_size;
1027
1028         reserve_map = (u64 *)(((unsigned long)initial_boot_params) +
1029                                         initial_boot_params->off_mem_rsvmap);
1030
1031         /* before we do anything, lets reserve the dt blob */
1032         self_base = __pa((unsigned long)initial_boot_params);
1033         self_size = initial_boot_params->totalsize;
1034         lmb_reserve(self_base, self_size);
1035
1036 #ifdef CONFIG_BLK_DEV_INITRD
1037         /* then reserve the initrd, if any */
1038         if (initrd_start && (initrd_end > initrd_start))
1039                 lmb_reserve(__pa(initrd_start), initrd_end - initrd_start);
1040 #endif /* CONFIG_BLK_DEV_INITRD */
1041
1042 #ifdef CONFIG_PPC32
1043         /*
1044          * Handle the case where we might be booting from an old kexec
1045          * image that setup the mem_rsvmap as pairs of 32-bit values
1046          */
1047         if (*reserve_map > 0xffffffffull) {
1048                 u32 base_32, size_32;
1049                 u32 *reserve_map_32 = (u32 *)reserve_map;
1050
1051                 while (1) {
1052                         base_32 = *(reserve_map_32++);
1053                         size_32 = *(reserve_map_32++);
1054                         if (size_32 == 0)
1055                                 break;
1056                         /* skip if the reservation is for the blob */
1057                         if (base_32 == self_base && size_32 == self_size)
1058                                 continue;
1059                         DBG("reserving: %x -> %x\n", base_32, size_32);
1060                         lmb_reserve(base_32, size_32);
1061                 }
1062                 return;
1063         }
1064 #endif
1065         while (1) {
1066                 base = *(reserve_map++);
1067                 size = *(reserve_map++);
1068                 if (size == 0)
1069                         break;
1070                 DBG("reserving: %llx -> %llx\n", base, size);
1071                 lmb_reserve(base, size);
1072         }
1073
1074 #if 0
1075         DBG("memory reserved, lmbs :\n");
1076         lmb_dump_all();
1077 #endif
1078 }
1079
1080 #ifdef CONFIG_PHYP_DUMP
1081 /**
1082  * phyp_dump_calculate_reserve_size() - reserve variable boot area 5% or arg
1083  *
1084  * Function to find the largest size we need to reserve
1085  * during early boot process.
1086  *
1087  * It either looks for boot param and returns that OR
1088  * returns larger of 256 or 5% rounded down to multiples of 256MB.
1089  *
1090  */
1091 static inline unsigned long phyp_dump_calculate_reserve_size(void)
1092 {
1093         unsigned long tmp;
1094
1095         if (phyp_dump_info->reserve_bootvar)
1096                 return phyp_dump_info->reserve_bootvar;
1097
1098         /* divide by 20 to get 5% of value */
1099         tmp = lmb_end_of_DRAM();
1100         do_div(tmp, 20);
1101
1102         /* round it down in multiples of 256 */
1103         tmp = tmp & ~0x0FFFFFFFUL;
1104
1105         return (tmp > PHYP_DUMP_RMR_END ? tmp : PHYP_DUMP_RMR_END);
1106 }
1107
1108 /**
1109  * phyp_dump_reserve_mem() - reserve all not-yet-dumped mmemory
1110  *
1111  * This routine may reserve memory regions in the kernel only
1112  * if the system is supported and a dump was taken in last
1113  * boot instance or if the hardware is supported and the
1114  * scratch area needs to be setup. In other instances it returns
1115  * without reserving anything. The memory in case of dump being
1116  * active is freed when the dump is collected (by userland tools).
1117  */
1118 static void __init phyp_dump_reserve_mem(void)
1119 {
1120         unsigned long base, size;
1121         unsigned long variable_reserve_size;
1122
1123         if (!phyp_dump_info->phyp_dump_configured) {
1124                 printk(KERN_ERR "Phyp-dump not supported on this hardware\n");
1125                 return;
1126         }
1127
1128         if (!phyp_dump_info->phyp_dump_at_boot) {
1129                 printk(KERN_INFO "Phyp-dump disabled at boot time\n");
1130                 return;
1131         }
1132
1133         variable_reserve_size = phyp_dump_calculate_reserve_size();
1134
1135         if (phyp_dump_info->phyp_dump_is_active) {
1136                 /* Reserve *everything* above RMR.Area freed by userland tools*/
1137                 base = variable_reserve_size;
1138                 size = lmb_end_of_DRAM() - base;
1139
1140                 /* XXX crashed_ram_end is wrong, since it may be beyond
1141                  * the memory_limit, it will need to be adjusted. */
1142                 lmb_reserve(base, size);
1143
1144                 phyp_dump_info->init_reserve_start = base;
1145                 phyp_dump_info->init_reserve_size = size;
1146         } else {
1147                 size = phyp_dump_info->cpu_state_size +
1148                         phyp_dump_info->hpte_region_size +
1149                         variable_reserve_size;
1150                 base = lmb_end_of_DRAM() - size;
1151                 lmb_reserve(base, size);
1152                 phyp_dump_info->init_reserve_start = base;
1153                 phyp_dump_info->init_reserve_size = size;
1154         }
1155 }
1156 #else
1157 static inline void __init phyp_dump_reserve_mem(void) {}
1158 #endif /* CONFIG_PHYP_DUMP  && CONFIG_PPC_RTAS */
1159
1160
1161 void __init early_init_devtree(void *params)
1162 {
1163         unsigned long limit;
1164
1165         DBG(" -> early_init_devtree(%p)\n", params);
1166
1167         /* Setup flat device-tree pointer */
1168         initial_boot_params = params;
1169
1170 #ifdef CONFIG_PPC_RTAS
1171         /* Some machines might need RTAS info for debugging, grab it now. */
1172         of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
1173 #endif
1174
1175 #ifdef CONFIG_PHYP_DUMP
1176         /* scan tree to see if dump occured during last boot */
1177         of_scan_flat_dt(early_init_dt_scan_phyp_dump, NULL);
1178 #endif
1179
1180         /* Retrieve various informations from the /chosen node of the
1181          * device-tree, including the platform type, initrd location and
1182          * size, TCE reserve, and more ...
1183          */
1184         of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
1185
1186         /* Scan memory nodes and rebuild LMBs */
1187         lmb_init();
1188         of_scan_flat_dt(early_init_dt_scan_root, NULL);
1189         of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1190
1191         /* Save command line for /proc/cmdline and then parse parameters */
1192         strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
1193         parse_early_param();
1194
1195         /* Reserve LMB regions used by kernel, initrd, dt, etc... */
1196         lmb_reserve(PHYSICAL_START, __pa(klimit) - PHYSICAL_START);
1197         /* If relocatable, reserve first 32k for interrupt vectors etc. */
1198         if (PHYSICAL_START > MEMORY_START)
1199                 lmb_reserve(MEMORY_START, 0x8000);
1200         reserve_kdump_trampoline();
1201         reserve_crashkernel();
1202         early_reserve_mem();
1203         phyp_dump_reserve_mem();
1204
1205         limit = memory_limit;
1206         if (! limit) {
1207                 unsigned long memsize;
1208
1209                 /* Ensure that total memory size is page-aligned, because
1210                  * otherwise mark_bootmem() gets upset. */
1211                 lmb_analyze();
1212                 memsize = lmb_phys_mem_size();
1213                 if ((memsize & PAGE_MASK) != memsize)
1214                         limit = memsize & PAGE_MASK;
1215         }
1216         lmb_enforce_memory_limit(limit);
1217
1218         lmb_analyze();
1219
1220         DBG("Phys. mem: %lx\n", lmb_phys_mem_size());
1221
1222         /* We may need to relocate the flat tree, do it now.
1223          * FIXME .. and the initrd too? */
1224         move_device_tree();
1225
1226         DBG("Scanning CPUs ...\n");
1227
1228         /* Retreive CPU related informations from the flat tree
1229          * (altivec support, boot CPU ID, ...)
1230          */
1231         of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
1232
1233         DBG(" <- early_init_devtree()\n");
1234 }
1235
1236
1237 /**
1238  * Indicates whether the root node has a given value in its
1239  * compatible property.
1240  */
1241 int machine_is_compatible(const char *compat)
1242 {
1243         struct device_node *root;
1244         int rc = 0;
1245
1246         root = of_find_node_by_path("/");
1247         if (root) {
1248                 rc = of_device_is_compatible(root, compat);
1249                 of_node_put(root);
1250         }
1251         return rc;
1252 }
1253 EXPORT_SYMBOL(machine_is_compatible);
1254
1255 /*******
1256  *
1257  * New implementation of the OF "find" APIs, return a refcounted
1258  * object, call of_node_put() when done.  The device tree and list
1259  * are protected by a rw_lock.
1260  *
1261  * Note that property management will need some locking as well,
1262  * this isn't dealt with yet.
1263  *
1264  *******/
1265
1266 /**
1267  *      of_find_node_by_phandle - Find a node given a phandle
1268  *      @handle:        phandle of the node to find
1269  *
1270  *      Returns a node pointer with refcount incremented, use
1271  *      of_node_put() on it when done.
1272  */
1273 struct device_node *of_find_node_by_phandle(phandle handle)
1274 {
1275         struct device_node *np;
1276
1277         read_lock(&devtree_lock);
1278         for (np = allnodes; np != 0; np = np->allnext)
1279                 if (np->linux_phandle == handle)
1280                         break;
1281         of_node_get(np);
1282         read_unlock(&devtree_lock);
1283         return np;
1284 }
1285 EXPORT_SYMBOL(of_find_node_by_phandle);
1286
1287 /**
1288  *      of_find_next_cache_node - Find a node's subsidiary cache
1289  *      @np:    node of type "cpu" or "cache"
1290  *
1291  *      Returns a node pointer with refcount incremented, use
1292  *      of_node_put() on it when done.  Caller should hold a reference
1293  *      to np.
1294  */
1295 struct device_node *of_find_next_cache_node(struct device_node *np)
1296 {
1297         struct device_node *child;
1298         const phandle *handle;
1299
1300         handle = of_get_property(np, "l2-cache", NULL);
1301         if (!handle)
1302                 handle = of_get_property(np, "next-level-cache", NULL);
1303
1304         if (handle)
1305                 return of_find_node_by_phandle(*handle);
1306
1307         /* OF on pmac has nodes instead of properties named "l2-cache"
1308          * beneath CPU nodes.
1309          */
1310         if (!strcmp(np->type, "cpu"))
1311                 for_each_child_of_node(np, child)
1312                         if (!strcmp(child->type, "cache"))
1313                                 return child;
1314
1315         return NULL;
1316 }
1317
1318 /**
1319  *      of_find_all_nodes - Get next node in global list
1320  *      @prev:  Previous node or NULL to start iteration
1321  *              of_node_put() will be called on it
1322  *
1323  *      Returns a node pointer with refcount incremented, use
1324  *      of_node_put() on it when done.
1325  */
1326 struct device_node *of_find_all_nodes(struct device_node *prev)
1327 {
1328         struct device_node *np;
1329
1330         read_lock(&devtree_lock);
1331         np = prev ? prev->allnext : allnodes;
1332         for (; np != 0; np = np->allnext)
1333                 if (of_node_get(np))
1334                         break;
1335         of_node_put(prev);
1336         read_unlock(&devtree_lock);
1337         return np;
1338 }
1339 EXPORT_SYMBOL(of_find_all_nodes);
1340
1341 /**
1342  *      of_node_get - Increment refcount of a node
1343  *      @node:  Node to inc refcount, NULL is supported to
1344  *              simplify writing of callers
1345  *
1346  *      Returns node.
1347  */
1348 struct device_node *of_node_get(struct device_node *node)
1349 {
1350         if (node)
1351                 kref_get(&node->kref);
1352         return node;
1353 }
1354 EXPORT_SYMBOL(of_node_get);
1355
1356 static inline struct device_node * kref_to_device_node(struct kref *kref)
1357 {
1358         return container_of(kref, struct device_node, kref);
1359 }
1360
1361 /**
1362  *      of_node_release - release a dynamically allocated node
1363  *      @kref:  kref element of the node to be released
1364  *
1365  *      In of_node_put() this function is passed to kref_put()
1366  *      as the destructor.
1367  */
1368 static void of_node_release(struct kref *kref)
1369 {
1370         struct device_node *node = kref_to_device_node(kref);
1371         struct property *prop = node->properties;
1372
1373         /* We should never be releasing nodes that haven't been detached. */
1374         if (!of_node_check_flag(node, OF_DETACHED)) {
1375                 printk("WARNING: Bad of_node_put() on %s\n", node->full_name);
1376                 dump_stack();
1377                 kref_init(&node->kref);
1378                 return;
1379         }
1380
1381         if (!of_node_check_flag(node, OF_DYNAMIC))
1382                 return;
1383
1384         while (prop) {
1385                 struct property *next = prop->next;
1386                 kfree(prop->name);
1387                 kfree(prop->value);
1388                 kfree(prop);
1389                 prop = next;
1390
1391                 if (!prop) {
1392                         prop = node->deadprops;
1393                         node->deadprops = NULL;
1394                 }
1395         }
1396         kfree(node->full_name);
1397         kfree(node->data);
1398         kfree(node);
1399 }
1400
1401 /**
1402  *      of_node_put - Decrement refcount of a node
1403  *      @node:  Node to dec refcount, NULL is supported to
1404  *              simplify writing of callers
1405  *
1406  */
1407 void of_node_put(struct device_node *node)
1408 {
1409         if (node)
1410                 kref_put(&node->kref, of_node_release);
1411 }
1412 EXPORT_SYMBOL(of_node_put);
1413
1414 /*
1415  * Plug a device node into the tree and global list.
1416  */
1417 void of_attach_node(struct device_node *np)
1418 {
1419         unsigned long flags;
1420
1421         write_lock_irqsave(&devtree_lock, flags);
1422         np->sibling = np->parent->child;
1423         np->allnext = allnodes;
1424         np->parent->child = np;
1425         allnodes = np;
1426         write_unlock_irqrestore(&devtree_lock, flags);
1427 }
1428
1429 /*
1430  * "Unplug" a node from the device tree.  The caller must hold
1431  * a reference to the node.  The memory associated with the node
1432  * is not freed until its refcount goes to zero.
1433  */
1434 void of_detach_node(struct device_node *np)
1435 {
1436         struct device_node *parent;
1437         unsigned long flags;
1438
1439         write_lock_irqsave(&devtree_lock, flags);
1440
1441         parent = np->parent;
1442         if (!parent)
1443                 goto out_unlock;
1444
1445         if (allnodes == np)
1446                 allnodes = np->allnext;
1447         else {
1448                 struct device_node *prev;
1449                 for (prev = allnodes;
1450                      prev->allnext != np;
1451                      prev = prev->allnext)
1452                         ;
1453                 prev->allnext = np->allnext;
1454         }
1455
1456         if (parent->child == np)
1457                 parent->child = np->sibling;
1458         else {
1459                 struct device_node *prevsib;
1460                 for (prevsib = np->parent->child;
1461                      prevsib->sibling != np;
1462                      prevsib = prevsib->sibling)
1463                         ;
1464                 prevsib->sibling = np->sibling;
1465         }
1466
1467         of_node_set_flag(np, OF_DETACHED);
1468
1469 out_unlock:
1470         write_unlock_irqrestore(&devtree_lock, flags);
1471 }
1472
1473 #ifdef CONFIG_PPC_PSERIES
1474 /*
1475  * Fix up the uninitialized fields in a new device node:
1476  * name, type and pci-specific fields
1477  */
1478
1479 static int of_finish_dynamic_node(struct device_node *node)
1480 {
1481         struct device_node *parent = of_get_parent(node);
1482         int err = 0;
1483         const phandle *ibm_phandle;
1484
1485         node->name = of_get_property(node, "name", NULL);
1486         node->type = of_get_property(node, "device_type", NULL);
1487
1488         if (!node->name)
1489                 node->name = "<NULL>";
1490         if (!node->type)
1491                 node->type = "<NULL>";
1492
1493         if (!parent) {
1494                 err = -ENODEV;
1495                 goto out;
1496         }
1497
1498         /* We don't support that function on PowerMac, at least
1499          * not yet
1500          */
1501         if (machine_is(powermac))
1502                 return -ENODEV;
1503
1504         /* fix up new node's linux_phandle field */
1505         if ((ibm_phandle = of_get_property(node, "ibm,phandle", NULL)))
1506                 node->linux_phandle = *ibm_phandle;
1507
1508 out:
1509         of_node_put(parent);
1510         return err;
1511 }
1512
1513 static int prom_reconfig_notifier(struct notifier_block *nb,
1514                                   unsigned long action, void *node)
1515 {
1516         int err;
1517
1518         switch (action) {
1519         case PSERIES_RECONFIG_ADD:
1520                 err = of_finish_dynamic_node(node);
1521                 if (err < 0) {
1522                         printk(KERN_ERR "finish_node returned %d\n", err);
1523                         err = NOTIFY_BAD;
1524                 }
1525                 break;
1526         default:
1527                 err = NOTIFY_DONE;
1528                 break;
1529         }
1530         return err;
1531 }
1532
1533 static struct notifier_block prom_reconfig_nb = {
1534         .notifier_call = prom_reconfig_notifier,
1535         .priority = 10, /* This one needs to run first */
1536 };
1537
1538 static int __init prom_reconfig_setup(void)
1539 {
1540         return pSeries_reconfig_notifier_register(&prom_reconfig_nb);
1541 }
1542 __initcall(prom_reconfig_setup);
1543 #endif
1544
1545 /*
1546  * Add a property to a node
1547  */
1548 int prom_add_property(struct device_node* np, struct property* prop)
1549 {
1550         struct property **next;
1551         unsigned long flags;
1552
1553         prop->next = NULL;
1554         write_lock_irqsave(&devtree_lock, flags);
1555         next = &np->properties;
1556         while (*next) {
1557                 if (strcmp(prop->name, (*next)->name) == 0) {
1558                         /* duplicate ! don't insert it */
1559                         write_unlock_irqrestore(&devtree_lock, flags);
1560                         return -1;
1561                 }
1562                 next = &(*next)->next;
1563         }
1564         *next = prop;
1565         write_unlock_irqrestore(&devtree_lock, flags);
1566
1567 #ifdef CONFIG_PROC_DEVICETREE
1568         /* try to add to proc as well if it was initialized */
1569         if (np->pde)
1570                 proc_device_tree_add_prop(np->pde, prop);
1571 #endif /* CONFIG_PROC_DEVICETREE */
1572
1573         return 0;
1574 }
1575
1576 /*
1577  * Remove a property from a node.  Note that we don't actually
1578  * remove it, since we have given out who-knows-how-many pointers
1579  * to the data using get-property.  Instead we just move the property
1580  * to the "dead properties" list, so it won't be found any more.
1581  */
1582 int prom_remove_property(struct device_node *np, struct property *prop)
1583 {
1584         struct property **next;
1585         unsigned long flags;
1586         int found = 0;
1587
1588         write_lock_irqsave(&devtree_lock, flags);
1589         next = &np->properties;
1590         while (*next) {
1591                 if (*next == prop) {
1592                         /* found the node */
1593                         *next = prop->next;
1594                         prop->next = np->deadprops;
1595                         np->deadprops = prop;
1596                         found = 1;
1597                         break;
1598                 }
1599                 next = &(*next)->next;
1600         }
1601         write_unlock_irqrestore(&devtree_lock, flags);
1602
1603         if (!found)
1604                 return -ENODEV;
1605
1606 #ifdef CONFIG_PROC_DEVICETREE
1607         /* try to remove the proc node as well */
1608         if (np->pde)
1609                 proc_device_tree_remove_prop(np->pde, prop);
1610 #endif /* CONFIG_PROC_DEVICETREE */
1611
1612         return 0;
1613 }
1614
1615 /*
1616  * Update a property in a node.  Note that we don't actually
1617  * remove it, since we have given out who-knows-how-many pointers
1618  * to the data using get-property.  Instead we just move the property
1619  * to the "dead properties" list, and add the new property to the
1620  * property list
1621  */
1622 int prom_update_property(struct device_node *np,
1623                          struct property *newprop,
1624                          struct property *oldprop)
1625 {
1626         struct property **next;
1627         unsigned long flags;
1628         int found = 0;
1629
1630         write_lock_irqsave(&devtree_lock, flags);
1631         next = &np->properties;
1632         while (*next) {
1633                 if (*next == oldprop) {
1634                         /* found the node */
1635                         newprop->next = oldprop->next;
1636                         *next = newprop;
1637                         oldprop->next = np->deadprops;
1638                         np->deadprops = oldprop;
1639                         found = 1;
1640                         break;
1641                 }
1642                 next = &(*next)->next;
1643         }
1644         write_unlock_irqrestore(&devtree_lock, flags);
1645
1646         if (!found)
1647                 return -ENODEV;
1648
1649 #ifdef CONFIG_PROC_DEVICETREE
1650         /* try to add to proc as well if it was initialized */
1651         if (np->pde)
1652                 proc_device_tree_update_prop(np->pde, newprop, oldprop);
1653 #endif /* CONFIG_PROC_DEVICETREE */
1654
1655         return 0;
1656 }
1657
1658
1659 /* Find the device node for a given logical cpu number, also returns the cpu
1660  * local thread number (index in ibm,interrupt-server#s) if relevant and
1661  * asked for (non NULL)
1662  */
1663 struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
1664 {
1665         int hardid;
1666         struct device_node *np;
1667
1668         hardid = get_hard_smp_processor_id(cpu);
1669
1670         for_each_node_by_type(np, "cpu") {
1671                 const u32 *intserv;
1672                 unsigned int plen, t;
1673
1674                 /* Check for ibm,ppc-interrupt-server#s. If it doesn't exist
1675                  * fallback to "reg" property and assume no threads
1676                  */
1677                 intserv = of_get_property(np, "ibm,ppc-interrupt-server#s",
1678                                 &plen);
1679                 if (intserv == NULL) {
1680                         const u32 *reg = of_get_property(np, "reg", NULL);
1681                         if (reg == NULL)
1682                                 continue;
1683                         if (*reg == hardid) {
1684                                 if (thread)
1685                                         *thread = 0;
1686                                 return np;
1687                         }
1688                 } else {
1689                         plen /= sizeof(u32);
1690                         for (t = 0; t < plen; t++) {
1691                                 if (hardid == intserv[t]) {
1692                                         if (thread)
1693                                                 *thread = t;
1694                                         return np;
1695                                 }
1696                         }
1697                 }
1698         }
1699         return NULL;
1700 }
1701 EXPORT_SYMBOL(of_get_cpu_node);
1702
1703 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
1704 static struct debugfs_blob_wrapper flat_dt_blob;
1705
1706 static int __init export_flat_device_tree(void)
1707 {
1708         struct dentry *d;
1709
1710         flat_dt_blob.data = initial_boot_params;
1711         flat_dt_blob.size = initial_boot_params->totalsize;
1712
1713         d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
1714                                 powerpc_debugfs_root, &flat_dt_blob);
1715         if (!d)
1716                 return 1;
1717
1718         return 0;
1719 }
1720 __initcall(export_flat_device_tree);
1721 #endif