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%llx\n", (unsigned long long)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, "slb-size", NULL);
 594         if (slb_size_ptr != NULL) {
 595                 mmu_slb_size = *slb_size_ptr;
 596                 return;
 597         }
 598         slb_size_ptr = of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
 599         if (slb_size_ptr != NULL) {
 600                 mmu_slb_size = *slb_size_ptr;
 601         }
 602 }
 603 #else
 604 #define check_cpu_slb_size(node) do { } while(0)
 605 #endif
 606
 607 static struct feature_property {
 608         const char *name;
 609         u32 min_value;
 610         unsigned long cpu_feature;
 611         unsigned long cpu_user_ftr;
 612 } feature_properties[] __initdata = {
 613 #ifdef CONFIG_ALTIVEC
 614         {"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
 615         {"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
 616 #endif /* CONFIG_ALTIVEC */
 617 #ifdef CONFIG_VSX
 618         /* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
 619         {"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
 620 #endif /* CONFIG_VSX */
 621 #ifdef CONFIG_PPC64
 622         {"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
 623         {"ibm,purr", 1, CPU_FTR_PURR, 0},
 624         {"ibm,spurr", 1, CPU_FTR_SPURR, 0},
 625 #endif /* CONFIG_PPC64 */
 626 };
 627
 628 #if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
 629 static inline void identical_pvr_fixup(unsigned long node)
 630 {
 631         unsigned int pvr;
 632         char *model = of_get_flat_dt_prop(node, "model", NULL);
 633
 634         /*
 635          * Since 440GR(x)/440EP(x) processors have the same pvr,
 636          * we check the node path and set bit 28 in the cur_cpu_spec
 637          * pvr for EP(x) processor version. This bit is always 0 in
 638          * the "real" pvr. Then we call identify_cpu again with
 639          * the new logical pvr to enable FPU support.
 640          */
 641         if (model && strstr(model, "440EP")) {
 642                 pvr = cur_cpu_spec->pvr_value | 0x8;
 643                 identify_cpu(0, pvr);
 644                 DBG("Using logical pvr %x for %s\n", pvr, model);
 645         }
 646 }
 647 #else
 648 #define identical_pvr_fixup(node) do { } while(0)
 649 #endif
 650
 651 static void __init check_cpu_feature_properties(unsigned long node)
 652 {
 653         unsigned long i;
 654         struct feature_property *fp = feature_properties;
 655         const u32 *prop;
 656
 657         for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
 658                 prop = of_get_flat_dt_prop(node, fp->name, NULL);
 659                 if (prop && *prop >= fp->min_value) {
 660                         cur_cpu_spec->cpu_features |= fp->cpu_feature;
 661                         cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
 662                 }
 663         }
 664 }
 665
 666 static int __init early_init_dt_scan_cpus(unsigned long node,
 667                                           const char *uname, int depth,
 668                                           void *data)
 669 {
 670         static int logical_cpuid = 0;
 671         char *type = of_get_flat_dt_prop(node, "device_type", NULL);
 672         const u32 *prop;
 673         const u32 *intserv;
 674         int i, nthreads;
 675         unsigned long len;
 676         int found = 0;
 677
 678         /* We are scanning "cpu" nodes only */
 679         if (type == NULL || strcmp(type, "cpu") != 0)
 680                 return 0;
 681
 682         /* Get physical cpuid */
 683         intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
 684         if (intserv) {
 685                 nthreads = len / sizeof(int);
 686         } else {
 687                 intserv = of_get_flat_dt_prop(node, "reg", NULL);
 688                 nthreads = 1;
 689         }
 690
 691         /*
 692          * Now see if any of these threads match our boot cpu.
 693          * NOTE: This must match the parsing done in smp_setup_cpu_maps.
 694          */
 695         for (i = 0; i < nthreads; i++) {
 696                 /*
 697                  * version 2 of the kexec param format adds the phys cpuid of
 698                  * booted proc.
 699                  */
 700                 if (initial_boot_params && initial_boot_params->version >= 2) {
 701                         if (intserv[i] ==
 702                                         initial_boot_params->boot_cpuid_phys) {
 703                                 found = 1;
 704                                 break;
 705                         }
 706                 } else {
 707                         /*
 708                          * Check if it's the boot-cpu, set it's hw index now,
 709                          * unfortunately this format did not support booting
 710                          * off secondary threads.
 711                          */
 712                         if (of_get_flat_dt_prop(node,
 713                                         "linux,boot-cpu", NULL) != NULL) {
 714                                 found = 1;
 715                                 break;
 716                         }
 717                 }
 718
 719 #ifdef CONFIG_SMP
 720                 /* logical cpu id is always 0 on UP kernels */
 721                 logical_cpuid++;
 722 #endif
 723         }
 724
 725         if (found) {
 726                 DBG("boot cpu: logical %d physical %d\n", logical_cpuid,
 727                         intserv[i]);
 728                 boot_cpuid = logical_cpuid;
 729                 set_hard_smp_processor_id(boot_cpuid, intserv[i]);
 730
 731                 /*
 732                  * PAPR defines "logical" PVR values for cpus that
 733                  * meet various levels of the architecture:
 734                  * 0x0f000001   Architecture version 2.04
 735                  * 0x0f000002   Architecture version 2.05
 736                  * If the cpu-version property in the cpu node contains
 737                  * such a value, we call identify_cpu again with the
 738                  * logical PVR value in order to use the cpu feature
 739                  * bits appropriate for the architecture level.
 740                  *
 741                  * A POWER6 partition in "POWER6 architected" mode
 742                  * uses the 0x0f000002 PVR value; in POWER5+ mode
 743                  * it uses 0x0f000001.
 744                  */
 745                 prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
 746                 if (prop && (*prop & 0xff000000) == 0x0f000000)
 747                         identify_cpu(0, *prop);
 748
 749                 identical_pvr_fixup(node);
 750         }
 751
 752         check_cpu_feature_properties(node);
 753         check_cpu_pa_features(node);
 754         check_cpu_slb_size(node);
 755
 756 #ifdef CONFIG_PPC_PSERIES
 757         if (nthreads > 1)
 758                 cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
 759         else
 760                 cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
 761 #endif
 762
 763         return 0;
 764 }
 765
 766 #ifdef CONFIG_BLK_DEV_INITRD
 767 static void __init early_init_dt_check_for_initrd(unsigned long node)
 768 {
 769         unsigned long l;
 770         u32 *prop;
 771
 772         DBG("Looking for initrd properties... ");
 773
 774         prop = of_get_flat_dt_prop(node, "linux,initrd-start", &l);
 775         if (prop) {
 776                 initrd_start = (unsigned long)__va(of_read_ulong(prop, l/4));
 777
 778                 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l);
 779                 if (prop) {
 780                         initrd_end = (unsigned long)
 781                                         __va(of_read_ulong(prop, l/4));
 782                         initrd_below_start_ok = 1;
 783                 } else {
 784                         initrd_start = 0;
 785                 }
 786         }
 787
 788         DBG("initrd_start=0x%lx  initrd_end=0x%lx\n", initrd_start, initrd_end);
 789 }
 790 #else
 791 static inline void early_init_dt_check_for_initrd(unsigned long node)
 792 {
 793 }
 794 #endif /* CONFIG_BLK_DEV_INITRD */
 795
 796 static int __init early_init_dt_scan_chosen(unsigned long node,
 797                                             const char *uname, int depth, void *data)
 798 {
 799         unsigned long *lprop;
 800         unsigned long l;
 801         char *p;
 802
 803         DBG("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
 804
 805         if (depth != 1 ||
 806             (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
 807                 return 0;
 808
 809 #ifdef CONFIG_PPC64
 810         /* check if iommu is forced on or off */
 811         if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
 812                 iommu_is_off = 1;
 813         if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
 814                 iommu_force_on = 1;
 815 #endif
 816
 817         /* mem=x on the command line is the preferred mechanism */
 818         lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
 819         if (lprop)
 820                 memory_limit = *lprop;
 821
 822 #ifdef CONFIG_PPC64
 823         lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
 824         if (lprop)
 825                 tce_alloc_start = *lprop;
 826         lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
 827         if (lprop)
 828                 tce_alloc_end = *lprop;
 829 #endif
 830
 831 #ifdef CONFIG_KEXEC
 832         lprop = of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
 833         if (lprop)
 834                 crashk_res.start = *lprop;
 835
 836         lprop = of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
 837         if (lprop)
 838                 crashk_res.end = crashk_res.start + *lprop - 1;
 839 #endif
 840
 841         early_init_dt_check_for_initrd(node);
 842
 843         /* Retreive command line */
 844         p = of_get_flat_dt_prop(node, "bootargs", &l);
 845         if (p != NULL && l > 0)
 846                 strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));
 847
 848 #ifdef CONFIG_CMDLINE
 849         if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
 850                 strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
 851 #endif /* CONFIG_CMDLINE */
 852
 853         DBG("Command line is: %s\n", cmd_line);
 854
 855         /* break now */
 856         return 1;
 857 }
 858
 859 static int __init early_init_dt_scan_root(unsigned long node,
 860                                           const char *uname, int depth, void *data)
 861 {
 862         u32 *prop;
 863
 864         if (depth != 0)
 865                 return 0;
 866
 867         prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
 868         dt_root_size_cells = (prop == NULL) ? 1 : *prop;
 869         DBG("dt_root_size_cells = %x\n", dt_root_size_cells);
 870
 871         prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
 872         dt_root_addr_cells = (prop == NULL) ? 2 : *prop;
 873         DBG("dt_root_addr_cells = %x\n", dt_root_addr_cells);
 874
 875         /* break now */
 876         return 1;
 877 }
 878
 879 static u64 __init dt_mem_next_cell(int s, cell_t **cellp)
 880 {
 881         cell_t *p = *cellp;
 882
 883         *cellp = p + s;
 884         return of_read_number(p, s);
 885 }
 886
 887 #ifdef CONFIG_PPC_PSERIES
 888 /*
 889  * Interpret the ibm,dynamic-memory property in the
 890  * /ibm,dynamic-reconfiguration-memory node.
 891  * This contains a list of memory blocks along with NUMA affinity
 892  * information.
 893  */
 894 static int __init early_init_dt_scan_drconf_memory(unsigned long node)
 895 {
 896         cell_t *dm, *ls, *usm;
 897         unsigned long l, n, flags;
 898         u64 base, size, lmb_size;
 899         unsigned int is_kexec_kdump = 0, rngs;
 900
 901         ls = of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
 902         if (ls == NULL || l < dt_root_size_cells * sizeof(cell_t))
 903                 return 0;
 904         lmb_size = dt_mem_next_cell(dt_root_size_cells, &ls);
 905
 906         dm = of_get_flat_dt_prop(node, "ibm,dynamic-memory", &l);
 907         if (dm == NULL || l < sizeof(cell_t))
 908                 return 0;
 909
 910         n = *dm++;      /* number of entries */
 911         if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(cell_t))
 912                 return 0;
 913
 914         /* check if this is a kexec/kdump kernel. */
 915         usm = of_get_flat_dt_prop(node, "linux,drconf-usable-memory",
 916                                                  &l);
 917         if (usm != NULL)
 918                 is_kexec_kdump = 1;
 919
 920         for (; n != 0; --n) {
 921                 base = dt_mem_next_cell(dt_root_addr_cells, &dm);
 922                 flags = dm[3];
 923                 /* skip DRC index, pad, assoc. list index, flags */
 924                 dm += 4;
 925                 /* skip this block if the reserved bit is set in flags (0x80)
 926                    or if the block is not assigned to this partition (0x8) */
 927                 if ((flags & 0x80) || !(flags & 0x8))
 928                         continue;
 929                 size = lmb_size;
 930                 rngs = 1;
 931                 if (is_kexec_kdump) {
 932                         /*
 933                          * For each lmb in ibm,dynamic-memory, a corresponding
 934                          * entry in linux,drconf-usable-memory property contains
 935                          * a counter 'p' followed by 'p' (base, size) duple.
 936                          * Now read the counter from
 937                          * linux,drconf-usable-memory property
 938                          */
 939                         rngs = dt_mem_next_cell(dt_root_size_cells, &usm);
 940                         if (!rngs) /* there are no (base, size) duple */
 941                                 continue;
 942                 }
 943                 do {
 944                         if (is_kexec_kdump) {
 945                                 base = dt_mem_next_cell(dt_root_addr_cells,
 946                                                          &usm);
 947                                 size = dt_mem_next_cell(dt_root_size_cells,
 948                                                          &usm);
 949                         }
 950                         if (iommu_is_off) {
 951                                 if (base >= 0x80000000ul)
 952                                         continue;
 953                                 if ((base + size) > 0x80000000ul)
 954                                         size = 0x80000000ul - base;
 955                         }
 956                         lmb_add(base, size);
 957                 } while (--rngs);
 958         }
 959         lmb_dump_all();
 960         return 0;
 961 }
 962 #else
 963 #define early_init_dt_scan_drconf_memory(node)  0
 964 #endif /* CONFIG_PPC_PSERIES */
 965
 966 static int __init early_init_dt_scan_memory(unsigned long node,
 967                                             const char *uname, int depth, void *data)
 968 {
 969         char *type = of_get_flat_dt_prop(node, "device_type", NULL);
 970         cell_t *reg, *endp;
 971         unsigned long l;
 972
 973         /* Look for the ibm,dynamic-reconfiguration-memory node */
 974         if (depth == 1 &&
 975             strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
 976                 return early_init_dt_scan_drconf_memory(node);
 977
 978         /* We are scanning "memory" nodes only */
 979         if (type == NULL) {
 980                 /*
 981                  * The longtrail doesn't have a device_type on the
 982                  * /memory node, so look for the node called /memory@0.
 983                  */
 984                 if (depth != 1 || strcmp(uname, "memory@0") != 0)
 985                         return 0;
 986         } else if (strcmp(type, "memory") != 0)
 987                 return 0;
 988
 989         reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
 990         if (reg == NULL)
 991                 reg = of_get_flat_dt_prop(node, "reg", &l);
 992         if (reg == NULL)
 993                 return 0;
 994
 995         endp = reg + (l / sizeof(cell_t));
 996
 997         DBG("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
 998             uname, l, reg[0], reg[1], reg[2], reg[3]);
 999
1000         while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1001                 u64 base, size;
1002
1003                 base = dt_mem_next_cell(dt_root_addr_cells, &reg);
1004                 size = dt_mem_next_cell(dt_root_size_cells, &reg);
1005
1006                 if (size == 0)
1007                         continue;
1008                 DBG(" - %llx ,  %llx\n", (unsigned long long)base,
1009                     (unsigned long long)size);
1010 #ifdef CONFIG_PPC64
1011                 if (iommu_is_off) {
1012                         if (base >= 0x80000000ul)
1013                                 continue;
1014                         if ((base + size) > 0x80000000ul)
1015                                 size = 0x80000000ul - base;
1016                 }
1017 #endif
1018                 lmb_add(base, size);
1019
1020                 memstart_addr = min((u64)memstart_addr, base);
1021         }
1022
1023         return 0;
1024 }
1025
1026 static void __init early_reserve_mem(void)
1027 {
1028         u64 base, size;
1029         u64 *reserve_map;
1030         unsigned long self_base;
1031         unsigned long self_size;
1032
1033         reserve_map = (u64 *)(((unsigned long)initial_boot_params) +
1034                                         initial_boot_params->off_mem_rsvmap);
1035
1036         /* before we do anything, lets reserve the dt blob */
1037         self_base = __pa((unsigned long)initial_boot_params);
1038         self_size = initial_boot_params->totalsize;
1039         lmb_reserve(self_base, self_size);
1040
1041 #ifdef CONFIG_BLK_DEV_INITRD
1042         /* then reserve the initrd, if any */
1043         if (initrd_start && (initrd_end > initrd_start))
1044                 lmb_reserve(__pa(initrd_start), initrd_end - initrd_start);
1045 #endif /* CONFIG_BLK_DEV_INITRD */
1046
1047 #ifdef CONFIG_PPC32
1048         /*
1049          * Handle the case where we might be booting from an old kexec
1050          * image that setup the mem_rsvmap as pairs of 32-bit values
1051          */
1052         if (*reserve_map > 0xffffffffull) {
1053                 u32 base_32, size_32;
1054                 u32 *reserve_map_32 = (u32 *)reserve_map;
1055
1056                 while (1) {
1057                         base_32 = *(reserve_map_32++);
1058                         size_32 = *(reserve_map_32++);
1059                         if (size_32 == 0)
1060                                 break;
1061                         /* skip if the reservation is for the blob */
1062                         if (base_32 == self_base && size_32 == self_size)
1063                                 continue;
1064                         DBG("reserving: %x -> %x\n", base_32, size_32);
1065                         lmb_reserve(base_32, size_32);
1066                 }
1067                 return;
1068         }
1069 #endif
1070         while (1) {
1071                 base = *(reserve_map++);
1072                 size = *(reserve_map++);
1073                 if (size == 0)
1074                         break;
1075                 DBG("reserving: %llx -> %llx\n", base, size);
1076                 lmb_reserve(base, size);
1077         }
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         phys_addr_t 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                 phys_addr_t 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         lmb_dump_all();
1220
1221         DBG("Phys. mem: %llx\n", lmb_phys_mem_size());
1222
1223         /* We may need to relocate the flat tree, do it now.
1224          * FIXME .. and the initrd too? */
1225         move_device_tree();
1226
1227         DBG("Scanning CPUs ...\n");
1228
1229         /* Retreive CPU related informations from the flat tree
1230          * (altivec support, boot CPU ID, ...)
1231          */
1232         of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
1233
1234         DBG(" <- early_init_devtree()\n");
1235 }
1236
1237
1238 /**
1239  * Indicates whether the root node has a given value in its
1240  * compatible property.
1241  */
1242 int machine_is_compatible(const char *compat)
1243 {
1244         struct device_node *root;
1245         int rc = 0;
1246
1247         root = of_find_node_by_path("/");
1248         if (root) {
1249                 rc = of_device_is_compatible(root, compat);
1250                 of_node_put(root);
1251         }
1252         return rc;
1253 }
1254 EXPORT_SYMBOL(machine_is_compatible);
1255
1256 /*******
1257  *
1258  * New implementation of the OF "find" APIs, return a refcounted
1259  * object, call of_node_put() when done.  The device tree and list
1260  * are protected by a rw_lock.
1261  *
1262  * Note that property management will need some locking as well,
1263  * this isn't dealt with yet.
1264  *
1265  *******/
1266
1267 /**
1268  *      of_find_node_by_phandle - Find a node given a phandle
1269  *      @handle:        phandle of the node to find
1270  *
1271  *      Returns a node pointer with refcount incremented, use
1272  *      of_node_put() on it when done.
1273  */
1274 struct device_node *of_find_node_by_phandle(phandle handle)
1275 {
1276         struct device_node *np;
1277
1278         read_lock(&devtree_lock);
1279         for (np = allnodes; np != 0; np = np->allnext)
1280                 if (np->linux_phandle == handle)
1281                         break;
1282         of_node_get(np);
1283         read_unlock(&devtree_lock);
1284         return np;
1285 }
1286 EXPORT_SYMBOL(of_find_node_by_phandle);
1287
1288 /**
1289  *      of_find_next_cache_node - Find a node's subsidiary cache
1290  *      @np:    node of type "cpu" or "cache"
1291  *
1292  *      Returns a node pointer with refcount incremented, use
1293  *      of_node_put() on it when done.  Caller should hold a reference
1294  *      to np.
1295  */
1296 struct device_node *of_find_next_cache_node(struct device_node *np)
1297 {
1298         struct device_node *child;
1299         const phandle *handle;
1300
1301         handle = of_get_property(np, "l2-cache", NULL);
1302         if (!handle)
1303                 handle = of_get_property(np, "next-level-cache", NULL);
1304
1305         if (handle)
1306                 return of_find_node_by_phandle(*handle);
1307
1308         /* OF on pmac has nodes instead of properties named "l2-cache"
1309          * beneath CPU nodes.
1310          */
1311         if (!strcmp(np->type, "cpu"))
1312                 for_each_child_of_node(np, child)
1313                         if (!strcmp(child->type, "cache"))
1314                                 return child;
1315
1316         return NULL;
1317 }
1318
1319 /**
1320  *      of_find_all_nodes - Get next node in global list
1321  *      @prev:  Previous node or NULL to start iteration
1322  *              of_node_put() will be called on it
1323  *
1324  *      Returns a node pointer with refcount incremented, use
1325  *      of_node_put() on it when done.
1326  */
1327 struct device_node *of_find_all_nodes(struct device_node *prev)
1328 {
1329         struct device_node *np;
1330
1331         read_lock(&devtree_lock);
1332         np = prev ? prev->allnext : allnodes;
1333         for (; np != 0; np = np->allnext)
1334                 if (of_node_get(np))
1335                         break;
1336         of_node_put(prev);
1337         read_unlock(&devtree_lock);
1338         return np;
1339 }
1340 EXPORT_SYMBOL(of_find_all_nodes);
1341
1342 /**
1343  *      of_node_get - Increment refcount of a node
1344  *      @node:  Node to inc refcount, NULL is supported to
1345  *              simplify writing of callers
1346  *
1347  *      Returns node.
1348  */
1349 struct device_node *of_node_get(struct device_node *node)
1350 {
1351         if (node)
1352                 kref_get(&node->kref);
1353         return node;
1354 }
1355 EXPORT_SYMBOL(of_node_get);
1356
1357 static inline struct device_node * kref_to_device_node(struct kref *kref)
1358 {
1359         return container_of(kref, struct device_node, kref);
1360 }
1361
1362 /**
1363  *      of_node_release - release a dynamically allocated node
1364  *      @kref:  kref element of the node to be released
1365  *
1366  *      In of_node_put() this function is passed to kref_put()
1367  *      as the destructor.
1368  */
1369 static void of_node_release(struct kref *kref)
1370 {
1371         struct device_node *node = kref_to_device_node(kref);
1372         struct property *prop = node->properties;
1373
1374         /* We should never be releasing nodes that haven't been detached. */
1375         if (!of_node_check_flag(node, OF_DETACHED)) {
1376                 printk("WARNING: Bad of_node_put() on %s\n", node->full_name);
1377                 dump_stack();
1378                 kref_init(&node->kref);
1379                 return;
1380         }
1381
1382         if (!of_node_check_flag(node, OF_DYNAMIC))
1383                 return;
1384
1385         while (prop) {
1386                 struct property *next = prop->next;
1387                 kfree(prop->name);
1388                 kfree(prop->value);
1389                 kfree(prop);
1390                 prop = next;
1391
1392                 if (!prop) {
1393                         prop = node->deadprops;
1394                         node->deadprops = NULL;
1395                 }
1396         }
1397         kfree(node->full_name);
1398         kfree(node->data);
1399         kfree(node);
1400 }
1401
1402 /**
1403  *      of_node_put - Decrement refcount of a node
1404  *      @node:  Node to dec refcount, NULL is supported to
1405  *              simplify writing of callers
1406  *
1407  */
1408 void of_node_put(struct device_node *node)
1409 {
1410         if (node)
1411                 kref_put(&node->kref, of_node_release);
1412 }
1413 EXPORT_SYMBOL(of_node_put);
1414
1415 /*
1416  * Plug a device node into the tree and global list.
1417  */
1418 void of_attach_node(struct device_node *np)
1419 {
1420         unsigned long flags;
1421
1422         write_lock_irqsave(&devtree_lock, flags);
1423         np->sibling = np->parent->child;
1424         np->allnext = allnodes;
1425         np->parent->child = np;
1426         allnodes = np;
1427         write_unlock_irqrestore(&devtree_lock, flags);
1428 }
1429
1430 /*
1431  * "Unplug" a node from the device tree.  The caller must hold
1432  * a reference to the node.  The memory associated with the node
1433  * is not freed until its refcount goes to zero.
1434  */
1435 void of_detach_node(struct device_node *np)
1436 {
1437         struct device_node *parent;
1438         unsigned long flags;
1439
1440         write_lock_irqsave(&devtree_lock, flags);
1441
1442         parent = np->parent;
1443         if (!parent)
1444                 goto out_unlock;
1445
1446         if (allnodes == np)
1447                 allnodes = np->allnext;
1448         else {
1449                 struct device_node *prev;
1450                 for (prev = allnodes;
1451                      prev->allnext != np;
1452                      prev = prev->allnext)
1453                         ;
1454                 prev->allnext = np->allnext;
1455         }
1456
1457         if (parent->child == np)
1458                 parent->child = np->sibling;
1459         else {
1460                 struct device_node *prevsib;
1461                 for (prevsib = np->parent->child;
1462                      prevsib->sibling != np;
1463                      prevsib = prevsib->sibling)
1464                         ;
1465                 prevsib->sibling = np->sibling;
1466         }
1467
1468         of_node_set_flag(np, OF_DETACHED);
1469
1470 out_unlock:
1471         write_unlock_irqrestore(&devtree_lock, flags);
1472 }
1473
1474 #ifdef CONFIG_PPC_PSERIES
1475 /*
1476  * Fix up the uninitialized fields in a new device node:
1477  * name, type and pci-specific fields
1478  */
1479
1480 static int of_finish_dynamic_node(struct device_node *node)
1481 {
1482         struct device_node *parent = of_get_parent(node);
1483         int err = 0;
1484         const phandle *ibm_phandle;
1485
1486         node->name = of_get_property(node, "name", NULL);
1487         node->type = of_get_property(node, "device_type", NULL);
1488
1489         if (!node->name)
1490                 node->name = "<NULL>";
1491         if (!node->type)
1492                 node->type = "<NULL>";
1493
1494         if (!parent) {
1495                 err = -ENODEV;
1496                 goto out;
1497         }
1498
1499         /* We don't support that function on PowerMac, at least
1500          * not yet
1501          */
1502         if (machine_is(powermac))
1503                 return -ENODEV;
1504
1505         /* fix up new node's linux_phandle field */
1506         if ((ibm_phandle = of_get_property(node, "ibm,phandle", NULL)))
1507                 node->linux_phandle = *ibm_phandle;
1508
1509 out:
1510         of_node_put(parent);
1511         return err;
1512 }
1513
1514 static int prom_reconfig_notifier(struct notifier_block *nb,
1515                                   unsigned long action, void *node)
1516 {
1517         int err;
1518
1519         switch (action) {
1520         case PSERIES_RECONFIG_ADD:
1521                 err = of_finish_dynamic_node(node);
1522                 if (err < 0) {
1523                         printk(KERN_ERR "finish_node returned %d\n", err);
1524                         err = NOTIFY_BAD;
1525                 }
1526                 break;
1527         default:
1528                 err = NOTIFY_DONE;
1529                 break;
1530         }
1531         return err;
1532 }
1533
1534 static struct notifier_block prom_reconfig_nb = {
1535         .notifier_call = prom_reconfig_notifier,
1536         .priority = 10, /* This one needs to run first */
1537 };
1538
1539 static int __init prom_reconfig_setup(void)
1540 {
1541         return pSeries_reconfig_notifier_register(&prom_reconfig_nb);
1542 }
1543 __initcall(prom_reconfig_setup);
1544 #endif
1545
1546 /*
1547  * Add a property to a node
1548  */
1549 int prom_add_property(struct device_node* np, struct property* prop)
1550 {
1551         struct property **next;
1552         unsigned long flags;
1553
1554         prop->next = NULL;
1555         write_lock_irqsave(&devtree_lock, flags);
1556         next = &np->properties;
1557         while (*next) {
1558                 if (strcmp(prop->name, (*next)->name) == 0) {
1559                         /* duplicate ! don't insert it */
1560                         write_unlock_irqrestore(&devtree_lock, flags);
1561                         return -1;
1562                 }
1563                 next = &(*next)->next;
1564         }
1565         *next = prop;
1566         write_unlock_irqrestore(&devtree_lock, flags);
1567
1568 #ifdef CONFIG_PROC_DEVICETREE
1569         /* try to add to proc as well if it was initialized */
1570         if (np->pde)
1571                 proc_device_tree_add_prop(np->pde, prop);
1572 #endif /* CONFIG_PROC_DEVICETREE */
1573
1574         return 0;
1575 }
1576
1577 /*
1578  * Remove a property from a node.  Note that we don't actually
1579  * remove it, since we have given out who-knows-how-many pointers
1580  * to the data using get-property.  Instead we just move the property
1581  * to the "dead properties" list, so it won't be found any more.
1582  */
1583 int prom_remove_property(struct device_node *np, struct property *prop)
1584 {
1585         struct property **next;
1586         unsigned long flags;
1587         int found = 0;
1588
1589         write_lock_irqsave(&devtree_lock, flags);
1590         next = &np->properties;
1591         while (*next) {
1592                 if (*next == prop) {
1593                         /* found the node */
1594                         *next = prop->next;
1595                         prop->next = np->deadprops;
1596                         np->deadprops = prop;
1597                         found = 1;
1598                         break;
1599                 }
1600                 next = &(*next)->next;
1601         }
1602         write_unlock_irqrestore(&devtree_lock, flags);
1603
1604         if (!found)
1605                 return -ENODEV;
1606
1607 #ifdef CONFIG_PROC_DEVICETREE
1608         /* try to remove the proc node as well */
1609         if (np->pde)
1610                 proc_device_tree_remove_prop(np->pde, prop);
1611 #endif /* CONFIG_PROC_DEVICETREE */
1612
1613         return 0;
1614 }
1615
1616 /*
1617  * Update a property in a node.  Note that we don't actually
1618  * remove it, since we have given out who-knows-how-many pointers
1619  * to the data using get-property.  Instead we just move the property
1620  * to the "dead properties" list, and add the new property to the
1621  * property list
1622  */
1623 int prom_update_property(struct device_node *np,
1624                          struct property *newprop,
1625                          struct property *oldprop)
1626 {
1627         struct property **next;
1628         unsigned long flags;
1629         int found = 0;
1630
1631         write_lock_irqsave(&devtree_lock, flags);
1632         next = &np->properties;
1633         while (*next) {
1634                 if (*next == oldprop) {
1635                         /* found the node */
1636                         newprop->next = oldprop->next;
1637                         *next = newprop;
1638                         oldprop->next = np->deadprops;
1639                         np->deadprops = oldprop;
1640                         found = 1;
1641                         break;
1642                 }
1643                 next = &(*next)->next;
1644         }
1645         write_unlock_irqrestore(&devtree_lock, flags);
1646
1647         if (!found)
1648                 return -ENODEV;
1649
1650 #ifdef CONFIG_PROC_DEVICETREE
1651         /* try to add to proc as well if it was initialized */
1652         if (np->pde)
1653                 proc_device_tree_update_prop(np->pde, newprop, oldprop);
1654 #endif /* CONFIG_PROC_DEVICETREE */
1655
1656         return 0;
1657 }
1658
1659
1660 /* Find the device node for a given logical cpu number, also returns the cpu
1661  * local thread number (index in ibm,interrupt-server#s) if relevant and
1662  * asked for (non NULL)
1663  */
1664 struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
1665 {
1666         int hardid;
1667         struct device_node *np;
1668
1669         hardid = get_hard_smp_processor_id(cpu);
1670
1671         for_each_node_by_type(np, "cpu") {
1672                 const u32 *intserv;
1673                 unsigned int plen, t;
1674
1675                 /* Check for ibm,ppc-interrupt-server#s. If it doesn't exist
1676                  * fallback to "reg" property and assume no threads
1677                  */
1678                 intserv = of_get_property(np, "ibm,ppc-interrupt-server#s",
1679                                 &plen);
1680                 if (intserv == NULL) {
1681                         const u32 *reg = of_get_property(np, "reg", NULL);
1682                         if (reg == NULL)
1683                                 continue;
1684                         if (*reg == hardid) {
1685                                 if (thread)
1686                                         *thread = 0;
1687                                 return np;
1688                         }
1689                 } else {
1690                         plen /= sizeof(u32);
1691                         for (t = 0; t < plen; t++) {
1692                                 if (hardid == intserv[t]) {
1693                                         if (thread)
1694                                                 *thread = t;
1695                                         return np;
1696                                 }
1697                         }
1698                 }
1699         }
1700         return NULL;
1701 }
1702 EXPORT_SYMBOL(of_get_cpu_node);
1703
1704 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
1705 static struct debugfs_blob_wrapper flat_dt_blob;
1706
1707 static int __init export_flat_device_tree(void)
1708 {
1709         struct dentry *d;
1710
1711         flat_dt_blob.data = initial_boot_params;
1712         flat_dt_blob.size = initial_boot_params->totalsize;
1713
1714         d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
1715                                 powerpc_debugfs_root, &flat_dt_blob);
1716         if (!d)
1717                 return 1;
1718
1719         return 0;
1720 }
1721 __initcall(export_flat_device_tree);
1722 #endif