linux/scripts/dtc/flattree.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
   4 */
   5
   6#include "dtc.h"
   7#include "srcpos.h"
   8
   9#define FTF_FULLPATH    0x1
  10#define FTF_VARALIGN    0x2
  11#define FTF_NAMEPROPS   0x4
  12#define FTF_BOOTCPUID   0x8
  13#define FTF_STRTABSIZE  0x10
  14#define FTF_STRUCTSIZE  0x20
  15#define FTF_NOPS        0x40
  16
  17static struct version_info {
  18        int version;
  19        int last_comp_version;
  20        int hdr_size;
  21        int flags;
  22} version_table[] = {
  23        {1, 1, FDT_V1_SIZE,
  24         FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS},
  25        {2, 1, FDT_V2_SIZE,
  26         FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS|FTF_BOOTCPUID},
  27        {3, 1, FDT_V3_SIZE,
  28         FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS|FTF_BOOTCPUID|FTF_STRTABSIZE},
  29        {16, 16, FDT_V3_SIZE,
  30         FTF_BOOTCPUID|FTF_STRTABSIZE|FTF_NOPS},
  31        {17, 16, FDT_V17_SIZE,
  32         FTF_BOOTCPUID|FTF_STRTABSIZE|FTF_STRUCTSIZE|FTF_NOPS},
  33};
  34
  35struct emitter {
  36        void (*cell)(void *, cell_t);
  37        void (*string)(void *, const char *, int);
  38        void (*align)(void *, int);
  39        void (*data)(void *, struct data);
  40        void (*beginnode)(void *, struct label *labels);
  41        void (*endnode)(void *, struct label *labels);
  42        void (*property)(void *, struct label *labels);
  43};
  44
  45static void bin_emit_cell(void *e, cell_t val)
  46{
  47        struct data *dtbuf = e;
  48
  49        *dtbuf = data_append_cell(*dtbuf, val);
  50}
  51
  52static void bin_emit_string(void *e, const char *str, int len)
  53{
  54        struct data *dtbuf = e;
  55
  56        if (len == 0)
  57                len = strlen(str);
  58
  59        *dtbuf = data_append_data(*dtbuf, str, len);
  60        *dtbuf = data_append_byte(*dtbuf, '\0');
  61}
  62
  63static void bin_emit_align(void *e, int a)
  64{
  65        struct data *dtbuf = e;
  66
  67        *dtbuf = data_append_align(*dtbuf, a);
  68}
  69
  70static void bin_emit_data(void *e, struct data d)
  71{
  72        struct data *dtbuf = e;
  73
  74        *dtbuf = data_append_data(*dtbuf, d.val, d.len);
  75}
  76
  77static void bin_emit_beginnode(void *e, struct label *labels)
  78{
  79        bin_emit_cell(e, FDT_BEGIN_NODE);
  80}
  81
  82static void bin_emit_endnode(void *e, struct label *labels)
  83{
  84        bin_emit_cell(e, FDT_END_NODE);
  85}
  86
  87static void bin_emit_property(void *e, struct label *labels)
  88{
  89        bin_emit_cell(e, FDT_PROP);
  90}
  91
  92static struct emitter bin_emitter = {
  93        .cell = bin_emit_cell,
  94        .string = bin_emit_string,
  95        .align = bin_emit_align,
  96        .data = bin_emit_data,
  97        .beginnode = bin_emit_beginnode,
  98        .endnode = bin_emit_endnode,
  99        .property = bin_emit_property,
 100};
 101
 102static void emit_label(FILE *f, const char *prefix, const char *label)
 103{
 104        fprintf(f, "\t.globl\t%s_%s\n", prefix, label);
 105        fprintf(f, "%s_%s:\n", prefix, label);
 106        fprintf(f, "_%s_%s:\n", prefix, label);
 107}
 108
 109static void emit_offset_label(FILE *f, const char *label, int offset)
 110{
 111        fprintf(f, "\t.globl\t%s\n", label);
 112        fprintf(f, "%s\t= . + %d\n", label, offset);
 113}
 114
 115#define ASM_EMIT_BELONG(f, fmt, ...) \
 116        { \
 117                fprintf((f), "\t.byte\t((" fmt ") >> 24) & 0xff\n", __VA_ARGS__); \
 118                fprintf((f), "\t.byte\t((" fmt ") >> 16) & 0xff\n", __VA_ARGS__); \
 119                fprintf((f), "\t.byte\t((" fmt ") >> 8) & 0xff\n", __VA_ARGS__); \
 120                fprintf((f), "\t.byte\t(" fmt ") & 0xff\n", __VA_ARGS__); \
 121        }
 122
 123static void asm_emit_cell(void *e, cell_t val)
 124{
 125        FILE *f = e;
 126
 127        fprintf(f, "\t.byte 0x%02x; .byte 0x%02x; .byte 0x%02x; .byte 0x%02x\n",
 128                (val >> 24) & 0xff, (val >> 16) & 0xff,
 129                (val >> 8) & 0xff, val & 0xff);
 130}
 131
 132static void asm_emit_string(void *e, const char *str, int len)
 133{
 134        FILE *f = e;
 135
 136        if (len != 0)
 137                fprintf(f, "\t.string\t\"%.*s\"\n", len, str);
 138        else
 139                fprintf(f, "\t.string\t\"%s\"\n", str);
 140}
 141
 142static void asm_emit_align(void *e, int a)
 143{
 144        FILE *f = e;
 145
 146        fprintf(f, "\t.balign\t%d, 0\n", a);
 147}
 148
 149static void asm_emit_data(void *e, struct data d)
 150{
 151        FILE *f = e;
 152        unsigned int off = 0;
 153        struct marker *m = d.markers;
 154
 155        for_each_marker_of_type(m, LABEL)
 156                emit_offset_label(f, m->ref, m->offset);
 157
 158        while ((d.len - off) >= sizeof(uint32_t)) {
 159                asm_emit_cell(e, dtb_ld32(d.val + off));
 160                off += sizeof(uint32_t);
 161        }
 162
 163        while ((d.len - off) >= 1) {
 164                fprintf(f, "\t.byte\t0x%hhx\n", d.val[off]);
 165                off += 1;
 166        }
 167
 168        assert(off == d.len);
 169}
 170
 171static void asm_emit_beginnode(void *e, struct label *labels)
 172{
 173        FILE *f = e;
 174        struct label *l;
 175
 176        for_each_label(labels, l) {
 177                fprintf(f, "\t.globl\t%s\n", l->label);
 178                fprintf(f, "%s:\n", l->label);
 179        }
 180        fprintf(f, "\t/* FDT_BEGIN_NODE */\n");
 181        asm_emit_cell(e, FDT_BEGIN_NODE);
 182}
 183
 184static void asm_emit_endnode(void *e, struct label *labels)
 185{
 186        FILE *f = e;
 187        struct label *l;
 188
 189        fprintf(f, "\t/* FDT_END_NODE */\n");
 190        asm_emit_cell(e, FDT_END_NODE);
 191        for_each_label(labels, l) {
 192                fprintf(f, "\t.globl\t%s_end\n", l->label);
 193                fprintf(f, "%s_end:\n", l->label);
 194        }
 195}
 196
 197static void asm_emit_property(void *e, struct label *labels)
 198{
 199        FILE *f = e;
 200        struct label *l;
 201
 202        for_each_label(labels, l) {
 203                fprintf(f, "\t.globl\t%s\n", l->label);
 204                fprintf(f, "%s:\n", l->label);
 205        }
 206        fprintf(f, "\t/* FDT_PROP */\n");
 207        asm_emit_cell(e, FDT_PROP);
 208}
 209
 210static struct emitter asm_emitter = {
 211        .cell = asm_emit_cell,
 212        .string = asm_emit_string,
 213        .align = asm_emit_align,
 214        .data = asm_emit_data,
 215        .beginnode = asm_emit_beginnode,
 216        .endnode = asm_emit_endnode,
 217        .property = asm_emit_property,
 218};
 219
 220static int stringtable_insert(struct data *d, const char *str)
 221{
 222        unsigned int i;
 223
 224        /* FIXME: do this more efficiently? */
 225
 226        for (i = 0; i < d->len; i++) {
 227                if (streq(str, d->val + i))
 228                        return i;
 229        }
 230
 231        *d = data_append_data(*d, str, strlen(str)+1);
 232        return i;
 233}
 234
 235static void flatten_tree(struct node *tree, struct emitter *emit,
 236                         void *etarget, struct data *strbuf,
 237                         struct version_info *vi)
 238{
 239        struct property *prop;
 240        struct node *child;
 241        bool seen_name_prop = false;
 242
 243        if (tree->deleted)
 244                return;
 245
 246        emit->beginnode(etarget, tree->labels);
 247
 248        if (vi->flags & FTF_FULLPATH)
 249                emit->string(etarget, tree->fullpath, 0);
 250        else
 251                emit->string(etarget, tree->name, 0);
 252
 253        emit->align(etarget, sizeof(cell_t));
 254
 255        for_each_property(tree, prop) {
 256                int nameoff;
 257
 258                if (streq(prop->name, "name"))
 259                        seen_name_prop = true;
 260
 261                nameoff = stringtable_insert(strbuf, prop->name);
 262
 263                emit->property(etarget, prop->labels);
 264                emit->cell(etarget, prop->val.len);
 265                emit->cell(etarget, nameoff);
 266
 267                if ((vi->flags & FTF_VARALIGN) && (prop->val.len >= 8))
 268                        emit->align(etarget, 8);
 269
 270                emit->data(etarget, prop->val);
 271                emit->align(etarget, sizeof(cell_t));
 272        }
 273
 274        if ((vi->flags & FTF_NAMEPROPS) && !seen_name_prop) {
 275                emit->property(etarget, NULL);
 276                emit->cell(etarget, tree->basenamelen+1);
 277                emit->cell(etarget, stringtable_insert(strbuf, "name"));
 278
 279                if ((vi->flags & FTF_VARALIGN) && ((tree->basenamelen+1) >= 8))
 280                        emit->align(etarget, 8);
 281
 282                emit->string(etarget, tree->name, tree->basenamelen);
 283                emit->align(etarget, sizeof(cell_t));
 284        }
 285
 286        for_each_child(tree, child) {
 287                flatten_tree(child, emit, etarget, strbuf, vi);
 288        }
 289
 290        emit->endnode(etarget, tree->labels);
 291}
 292
 293static struct data flatten_reserve_list(struct reserve_info *reservelist,
 294                                 struct version_info *vi)
 295{
 296        struct reserve_info *re;
 297        struct data d = empty_data;
 298        int    j;
 299
 300        for (re = reservelist; re; re = re->next) {
 301                d = data_append_re(d, re->address, re->size);
 302        }
 303        /*
 304         * Add additional reserved slots if the user asked for them.
 305         */
 306        for (j = 0; j < reservenum; j++) {
 307                d = data_append_re(d, 0, 0);
 308        }
 309
 310        return d;
 311}
 312
 313static void make_fdt_header(struct fdt_header *fdt,
 314                            struct version_info *vi,
 315                            int reservesize, int dtsize, int strsize,
 316                            int boot_cpuid_phys)
 317{
 318        int reserve_off;
 319
 320        reservesize += sizeof(struct fdt_reserve_entry);
 321
 322        memset(fdt, 0xff, sizeof(*fdt));
 323
 324        fdt->magic = cpu_to_fdt32(FDT_MAGIC);
 325        fdt->version = cpu_to_fdt32(vi->version);
 326        fdt->last_comp_version = cpu_to_fdt32(vi->last_comp_version);
 327
 328        /* Reserve map should be doubleword aligned */
 329        reserve_off = ALIGN(vi->hdr_size, 8);
 330
 331        fdt->off_mem_rsvmap = cpu_to_fdt32(reserve_off);
 332        fdt->off_dt_struct = cpu_to_fdt32(reserve_off + reservesize);
 333        fdt->off_dt_strings = cpu_to_fdt32(reserve_off + reservesize
 334                                          + dtsize);
 335        fdt->totalsize = cpu_to_fdt32(reserve_off + reservesize + dtsize + strsize);
 336
 337        if (vi->flags & FTF_BOOTCPUID)
 338                fdt->boot_cpuid_phys = cpu_to_fdt32(boot_cpuid_phys);
 339        if (vi->flags & FTF_STRTABSIZE)
 340                fdt->size_dt_strings = cpu_to_fdt32(strsize);
 341        if (vi->flags & FTF_STRUCTSIZE)
 342                fdt->size_dt_struct = cpu_to_fdt32(dtsize);
 343}
 344
 345void dt_to_blob(FILE *f, struct dt_info *dti, int version)
 346{
 347        struct version_info *vi = NULL;
 348        unsigned int i;
 349        struct data blob       = empty_data;
 350        struct data reservebuf = empty_data;
 351        struct data dtbuf      = empty_data;
 352        struct data strbuf     = empty_data;
 353        struct fdt_header fdt;
 354        int padlen = 0;
 355
 356        for (i = 0; i < ARRAY_SIZE(version_table); i++) {
 357                if (version_table[i].version == version)
 358                        vi = &version_table[i];
 359        }
 360        if (!vi)
 361                die("Unknown device tree blob version %d\n", version);
 362
 363        flatten_tree(dti->dt, &bin_emitter, &dtbuf, &strbuf, vi);
 364        bin_emit_cell(&dtbuf, FDT_END);
 365
 366        reservebuf = flatten_reserve_list(dti->reservelist, vi);
 367
 368        /* Make header */
 369        make_fdt_header(&fdt, vi, reservebuf.len, dtbuf.len, strbuf.len,
 370                        dti->boot_cpuid_phys);
 371
 372        /*
 373         * If the user asked for more space than is used, adjust the totalsize.
 374         */
 375        if (minsize > 0) {
 376                padlen = minsize - fdt32_to_cpu(fdt.totalsize);
 377                if (padlen < 0) {
 378                        padlen = 0;
 379                        if (quiet < 1)
 380                                fprintf(stderr,
 381                                        "Warning: blob size %"PRIu32" >= minimum size %d\n",
 382                                        fdt32_to_cpu(fdt.totalsize), minsize);
 383                }
 384        }
 385
 386        if (padsize > 0)
 387                padlen = padsize;
 388
 389        if (alignsize > 0)
 390                padlen = ALIGN(fdt32_to_cpu(fdt.totalsize) + padlen, alignsize)
 391                        - fdt32_to_cpu(fdt.totalsize);
 392
 393        if (padlen > 0) {
 394                int tsize = fdt32_to_cpu(fdt.totalsize);
 395                tsize += padlen;
 396                fdt.totalsize = cpu_to_fdt32(tsize);
 397        }
 398
 399        /*
 400         * Assemble the blob: start with the header, add with alignment
 401         * the reserve buffer, add the reserve map terminating zeroes,
 402         * the device tree itself, and finally the strings.
 403         */
 404        blob = data_append_data(blob, &fdt, vi->hdr_size);
 405        blob = data_append_align(blob, 8);
 406        blob = data_merge(blob, reservebuf);
 407        blob = data_append_zeroes(blob, sizeof(struct fdt_reserve_entry));
 408        blob = data_merge(blob, dtbuf);
 409        blob = data_merge(blob, strbuf);
 410
 411        /*
 412         * If the user asked for more space than is used, pad out the blob.
 413         */
 414        if (padlen > 0)
 415                blob = data_append_zeroes(blob, padlen);
 416
 417        if (fwrite(blob.val, blob.len, 1, f) != 1) {
 418                if (ferror(f))
 419                        die("Error writing device tree blob: %s\n",
 420                            strerror(errno));
 421                else
 422                        die("Short write on device tree blob\n");
 423        }
 424
 425        /*
 426         * data_merge() frees the right-hand element so only the blob
 427         * remains to be freed.
 428         */
 429        data_free(blob);
 430}
 431
 432static void dump_stringtable_asm(FILE *f, struct data strbuf)
 433{
 434        const char *p;
 435        int len;
 436
 437        p = strbuf.val;
 438
 439        while (p < (strbuf.val + strbuf.len)) {
 440                len = strlen(p);
 441                fprintf(f, "\t.string \"%s\"\n", p);
 442                p += len+1;
 443        }
 444}
 445
 446void dt_to_asm(FILE *f, struct dt_info *dti, int version)
 447{
 448        struct version_info *vi = NULL;
 449        unsigned int i;
 450        struct data strbuf = empty_data;
 451        struct reserve_info *re;
 452        const char *symprefix = "dt";
 453
 454        for (i = 0; i < ARRAY_SIZE(version_table); i++) {
 455                if (version_table[i].version == version)
 456                        vi = &version_table[i];
 457        }
 458        if (!vi)
 459                die("Unknown device tree blob version %d\n", version);
 460
 461        fprintf(f, "/* autogenerated by dtc, do not edit */\n\n");
 462
 463        emit_label(f, symprefix, "blob_start");
 464        emit_label(f, symprefix, "header");
 465        fprintf(f, "\t/* magic */\n");
 466        asm_emit_cell(f, FDT_MAGIC);
 467        fprintf(f, "\t/* totalsize */\n");
 468        ASM_EMIT_BELONG(f, "_%s_blob_abs_end - _%s_blob_start",
 469                        symprefix, symprefix);
 470        fprintf(f, "\t/* off_dt_struct */\n");
 471        ASM_EMIT_BELONG(f, "_%s_struct_start - _%s_blob_start",
 472                symprefix, symprefix);
 473        fprintf(f, "\t/* off_dt_strings */\n");
 474        ASM_EMIT_BELONG(f, "_%s_strings_start - _%s_blob_start",
 475                symprefix, symprefix);
 476        fprintf(f, "\t/* off_mem_rsvmap */\n");
 477        ASM_EMIT_BELONG(f, "_%s_reserve_map - _%s_blob_start",
 478                symprefix, symprefix);
 479        fprintf(f, "\t/* version */\n");
 480        asm_emit_cell(f, vi->version);
 481        fprintf(f, "\t/* last_comp_version */\n");
 482        asm_emit_cell(f, vi->last_comp_version);
 483
 484        if (vi->flags & FTF_BOOTCPUID) {
 485                fprintf(f, "\t/* boot_cpuid_phys */\n");
 486                asm_emit_cell(f, dti->boot_cpuid_phys);
 487        }
 488
 489        if (vi->flags & FTF_STRTABSIZE) {
 490                fprintf(f, "\t/* size_dt_strings */\n");
 491                ASM_EMIT_BELONG(f, "_%s_strings_end - _%s_strings_start",
 492                                symprefix, symprefix);
 493        }
 494
 495        if (vi->flags & FTF_STRUCTSIZE) {
 496                fprintf(f, "\t/* size_dt_struct */\n");
 497                ASM_EMIT_BELONG(f, "_%s_struct_end - _%s_struct_start",
 498                        symprefix, symprefix);
 499        }
 500
 501        /*
 502         * Reserve map entries.
 503         * Align the reserve map to a doubleword boundary.
 504         * Each entry is an (address, size) pair of u64 values.
 505         * Always supply a zero-sized temination entry.
 506         */
 507        asm_emit_align(f, 8);
 508        emit_label(f, symprefix, "reserve_map");
 509
 510        fprintf(f, "/* Memory reserve map from source file */\n");
 511
 512        /*
 513         * Use .long on high and low halves of u64s to avoid .quad
 514         * as it appears .quad isn't available in some assemblers.
 515         */
 516        for (re = dti->reservelist; re; re = re->next) {
 517                struct label *l;
 518
 519                for_each_label(re->labels, l) {
 520                        fprintf(f, "\t.globl\t%s\n", l->label);
 521                        fprintf(f, "%s:\n", l->label);
 522                }
 523                ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->address >> 32));
 524                ASM_EMIT_BELONG(f, "0x%08x",
 525                                (unsigned int)(re->address & 0xffffffff));
 526                ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->size >> 32));
 527                ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->size & 0xffffffff));
 528        }
 529        for (i = 0; i < reservenum; i++) {
 530                fprintf(f, "\t.long\t0, 0\n\t.long\t0, 0\n");
 531        }
 532
 533        fprintf(f, "\t.long\t0, 0\n\t.long\t0, 0\n");
 534
 535        emit_label(f, symprefix, "struct_start");
 536        flatten_tree(dti->dt, &asm_emitter, f, &strbuf, vi);
 537
 538        fprintf(f, "\t/* FDT_END */\n");
 539        asm_emit_cell(f, FDT_END);
 540        emit_label(f, symprefix, "struct_end");
 541
 542        emit_label(f, symprefix, "strings_start");
 543        dump_stringtable_asm(f, strbuf);
 544        emit_label(f, symprefix, "strings_end");
 545
 546        emit_label(f, symprefix, "blob_end");
 547
 548        /*
 549         * If the user asked for more space than is used, pad it out.
 550         */
 551        if (minsize > 0) {
 552                fprintf(f, "\t.space\t%d - (_%s_blob_end - _%s_blob_start), 0\n",
 553                        minsize, symprefix, symprefix);
 554        }
 555        if (padsize > 0) {
 556                fprintf(f, "\t.space\t%d, 0\n", padsize);
 557        }
 558        if (alignsize > 0)
 559                asm_emit_align(f, alignsize);
 560        emit_label(f, symprefix, "blob_abs_end");
 561
 562        data_free(strbuf);
 563}
 564
 565struct inbuf {
 566        char *base, *limit, *ptr;
 567};
 568
 569static void inbuf_init(struct inbuf *inb, void *base, void *limit)
 570{
 571        inb->base = base;
 572        inb->limit = limit;
 573        inb->ptr = inb->base;
 574}
 575
 576static void flat_read_chunk(struct inbuf *inb, void *p, int len)
 577{
 578        if ((inb->ptr + len) > inb->limit)
 579                die("Premature end of data parsing flat device tree\n");
 580
 581        memcpy(p, inb->ptr, len);
 582
 583        inb->ptr += len;
 584}
 585
 586static uint32_t flat_read_word(struct inbuf *inb)
 587{
 588        fdt32_t val;
 589
 590        assert(((inb->ptr - inb->base) % sizeof(val)) == 0);
 591
 592        flat_read_chunk(inb, &val, sizeof(val));
 593
 594        return fdt32_to_cpu(val);
 595}
 596
 597static void flat_realign(struct inbuf *inb, int align)
 598{
 599        int off = inb->ptr - inb->base;
 600
 601        inb->ptr = inb->base + ALIGN(off, align);
 602        if (inb->ptr > inb->limit)
 603                die("Premature end of data parsing flat device tree\n");
 604}
 605
 606static char *flat_read_string(struct inbuf *inb)
 607{
 608        int len = 0;
 609        const char *p = inb->ptr;
 610        char *str;
 611
 612        do {
 613                if (p >= inb->limit)
 614                        die("Premature end of data parsing flat device tree\n");
 615                len++;
 616        } while ((*p++) != '\0');
 617
 618        str = xstrdup(inb->ptr);
 619
 620        inb->ptr += len;
 621
 622        flat_realign(inb, sizeof(uint32_t));
 623
 624        return str;
 625}
 626
 627static struct data flat_read_data(struct inbuf *inb, int len)
 628{
 629        struct data d = empty_data;
 630
 631        if (len == 0)
 632                return empty_data;
 633
 634        d = data_grow_for(d, len);
 635        d.len = len;
 636
 637        flat_read_chunk(inb, d.val, len);
 638
 639        flat_realign(inb, sizeof(uint32_t));
 640
 641        return d;
 642}
 643
 644static char *flat_read_stringtable(struct inbuf *inb, int offset)
 645{
 646        const char *p;
 647
 648        p = inb->base + offset;
 649        while (1) {
 650                if (p >= inb->limit || p < inb->base)
 651                        die("String offset %d overruns string table\n",
 652                            offset);
 653
 654                if (*p == '\0')
 655                        break;
 656
 657                p++;
 658        }
 659
 660        return xstrdup(inb->base + offset);
 661}
 662
 663static struct property *flat_read_property(struct inbuf *dtbuf,
 664                                           struct inbuf *strbuf, int flags)
 665{
 666        uint32_t proplen, stroff;
 667        char *name;
 668        struct data val;
 669
 670        proplen = flat_read_word(dtbuf);
 671        stroff = flat_read_word(dtbuf);
 672
 673        name = flat_read_stringtable(strbuf, stroff);
 674
 675        if ((flags & FTF_VARALIGN) && (proplen >= 8))
 676                flat_realign(dtbuf, 8);
 677
 678        val = flat_read_data(dtbuf, proplen);
 679
 680        return build_property(name, val, NULL);
 681}
 682
 683
 684static struct reserve_info *flat_read_mem_reserve(struct inbuf *inb)
 685{
 686        struct reserve_info *reservelist = NULL;
 687        struct reserve_info *new;
 688        struct fdt_reserve_entry re;
 689
 690        /*
 691         * Each entry is a pair of u64 (addr, size) values for 4 cell_t's.
 692         * List terminates at an entry with size equal to zero.
 693         *
 694         * First pass, count entries.
 695         */
 696        while (1) {
 697                uint64_t address, size;
 698
 699                flat_read_chunk(inb, &re, sizeof(re));
 700                address  = fdt64_to_cpu(re.address);
 701                size = fdt64_to_cpu(re.size);
 702                if (size == 0)
 703                        break;
 704
 705                new = build_reserve_entry(address, size);
 706                reservelist = add_reserve_entry(reservelist, new);
 707        }
 708
 709        return reservelist;
 710}
 711
 712
 713static char *nodename_from_path(const char *ppath, const char *cpath)
 714{
 715        int plen;
 716
 717        plen = strlen(ppath);
 718
 719        if (!strstarts(cpath, ppath))
 720                die("Path \"%s\" is not valid as a child of \"%s\"\n",
 721                    cpath, ppath);
 722
 723        /* root node is a special case */
 724        if (!streq(ppath, "/"))
 725                plen++;
 726
 727        return xstrdup(cpath + plen);
 728}
 729
 730static struct node *unflatten_tree(struct inbuf *dtbuf,
 731                                   struct inbuf *strbuf,
 732                                   const char *parent_flatname, int flags)
 733{
 734        struct node *node;
 735        char *flatname;
 736        uint32_t val;
 737
 738        node = build_node(NULL, NULL, NULL);
 739
 740        flatname = flat_read_string(dtbuf);
 741
 742        if (flags & FTF_FULLPATH)
 743                node->name = nodename_from_path(parent_flatname, flatname);
 744        else
 745                node->name = flatname;
 746
 747        do {
 748                struct property *prop;
 749                struct node *child;
 750
 751                val = flat_read_word(dtbuf);
 752                switch (val) {
 753                case FDT_PROP:
 754                        if (node->children)
 755                                fprintf(stderr, "Warning: Flat tree input has "
 756                                        "subnodes preceding a property.\n");
 757                        prop = flat_read_property(dtbuf, strbuf, flags);
 758                        add_property(node, prop);
 759                        break;
 760
 761                case FDT_BEGIN_NODE:
 762                        child = unflatten_tree(dtbuf,strbuf, flatname, flags);
 763                        add_child(node, child);
 764                        break;
 765
 766                case FDT_END_NODE:
 767                        break;
 768
 769                case FDT_END:
 770                        die("Premature FDT_END in device tree blob\n");
 771                        break;
 772
 773                case FDT_NOP:
 774                        if (!(flags & FTF_NOPS))
 775                                fprintf(stderr, "Warning: NOP tag found in flat tree"
 776                                        " version <16\n");
 777
 778                        /* Ignore */
 779                        break;
 780
 781                default:
 782                        die("Invalid opcode word %08x in device tree blob\n",
 783                            val);
 784                }
 785        } while (val != FDT_END_NODE);
 786
 787        if (node->name != flatname) {
 788                free(flatname);
 789        }
 790
 791        return node;
 792}
 793
 794
 795struct dt_info *dt_from_blob(const char *fname)
 796{
 797        FILE *f;
 798        fdt32_t magic_buf, totalsize_buf;
 799        uint32_t magic, totalsize, version, size_dt, boot_cpuid_phys;
 800        uint32_t off_dt, off_str, off_mem_rsvmap;
 801        int rc;
 802        char *blob;
 803        struct fdt_header *fdt;
 804        char *p;
 805        struct inbuf dtbuf, strbuf;
 806        struct inbuf memresvbuf;
 807        int sizeleft;
 808        struct reserve_info *reservelist;
 809        struct node *tree;
 810        uint32_t val;
 811        int flags = 0;
 812
 813        f = srcfile_relative_open(fname, NULL);
 814
 815        rc = fread(&magic_buf, sizeof(magic_buf), 1, f);
 816        if (ferror(f))
 817                die("Error reading DT blob magic number: %s\n",
 818                    strerror(errno));
 819        if (rc < 1) {
 820                if (feof(f))
 821                        die("EOF reading DT blob magic number\n");
 822                else
 823                        die("Mysterious short read reading magic number\n");
 824        }
 825
 826        magic = fdt32_to_cpu(magic_buf);
 827        if (magic != FDT_MAGIC)
 828                die("Blob has incorrect magic number\n");
 829
 830        rc = fread(&totalsize_buf, sizeof(totalsize_buf), 1, f);
 831        if (ferror(f))
 832                die("Error reading DT blob size: %s\n", strerror(errno));
 833        if (rc < 1) {
 834                if (feof(f))
 835                        die("EOF reading DT blob size\n");
 836                else
 837                        die("Mysterious short read reading blob size\n");
 838        }
 839
 840        totalsize = fdt32_to_cpu(totalsize_buf);
 841        if (totalsize < FDT_V1_SIZE)
 842                die("DT blob size (%d) is too small\n", totalsize);
 843
 844        blob = xmalloc(totalsize);
 845
 846        fdt = (struct fdt_header *)blob;
 847        fdt->magic = cpu_to_fdt32(magic);
 848        fdt->totalsize = cpu_to_fdt32(totalsize);
 849
 850        sizeleft = totalsize - sizeof(magic) - sizeof(totalsize);
 851        p = blob + sizeof(magic)  + sizeof(totalsize);
 852
 853        while (sizeleft) {
 854                if (feof(f))
 855                        die("EOF before reading %d bytes of DT blob\n",
 856                            totalsize);
 857
 858                rc = fread(p, 1, sizeleft, f);
 859                if (ferror(f))
 860                        die("Error reading DT blob: %s\n",
 861                            strerror(errno));
 862
 863                sizeleft -= rc;
 864                p += rc;
 865        }
 866
 867        off_dt = fdt32_to_cpu(fdt->off_dt_struct);
 868        off_str = fdt32_to_cpu(fdt->off_dt_strings);
 869        off_mem_rsvmap = fdt32_to_cpu(fdt->off_mem_rsvmap);
 870        version = fdt32_to_cpu(fdt->version);
 871        boot_cpuid_phys = fdt32_to_cpu(fdt->boot_cpuid_phys);
 872
 873        if (off_mem_rsvmap >= totalsize)
 874                die("Mem Reserve structure offset exceeds total size\n");
 875
 876        if (off_dt >= totalsize)
 877                die("DT structure offset exceeds total size\n");
 878
 879        if (off_str > totalsize)
 880                die("String table offset exceeds total size\n");
 881
 882        if (version >= 3) {
 883                uint32_t size_str = fdt32_to_cpu(fdt->size_dt_strings);
 884                if ((off_str+size_str < off_str) || (off_str+size_str > totalsize))
 885                        die("String table extends past total size\n");
 886                inbuf_init(&strbuf, blob + off_str, blob + off_str + size_str);
 887        } else {
 888                inbuf_init(&strbuf, blob + off_str, blob + totalsize);
 889        }
 890
 891        if (version >= 17) {
 892                size_dt = fdt32_to_cpu(fdt->size_dt_struct);
 893                if ((off_dt+size_dt < off_dt) || (off_dt+size_dt > totalsize))
 894                        die("Structure block extends past total size\n");
 895        }
 896
 897        if (version < 16) {
 898                flags |= FTF_FULLPATH | FTF_NAMEPROPS | FTF_VARALIGN;
 899        } else {
 900                flags |= FTF_NOPS;
 901        }
 902
 903        inbuf_init(&memresvbuf,
 904                   blob + off_mem_rsvmap, blob + totalsize);
 905        inbuf_init(&dtbuf, blob + off_dt, blob + totalsize);
 906
 907        reservelist = flat_read_mem_reserve(&memresvbuf);
 908
 909        val = flat_read_word(&dtbuf);
 910
 911        if (val != FDT_BEGIN_NODE)
 912                die("Device tree blob doesn't begin with FDT_BEGIN_NODE (begins with 0x%08x)\n", val);
 913
 914        tree = unflatten_tree(&dtbuf, &strbuf, "", flags);
 915
 916        val = flat_read_word(&dtbuf);
 917        if (val != FDT_END)
 918                die("Device tree blob doesn't end with FDT_END\n");
 919
 920        free(blob);
 921
 922        fclose(f);
 923
 924        return build_dt_info(DTSF_V1, reservelist, tree, boot_cpuid_phys);
 925}
 926