flattree.c 22.2 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
/*
 * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
 *
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *                                                                   USA
 */

#include "dtc.h"
22
#include "srcpos.h"
23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51

#define FTF_FULLPATH	0x1
#define FTF_VARALIGN	0x2
#define FTF_NAMEPROPS	0x4
#define FTF_BOOTCPUID	0x8
#define FTF_STRTABSIZE	0x10
#define FTF_STRUCTSIZE	0x20
#define FTF_NOPS	0x40

static struct version_info {
	int version;
	int last_comp_version;
	int hdr_size;
	int flags;
} version_table[] = {
	{1, 1, FDT_V1_SIZE,
	 FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS},
	{2, 1, FDT_V2_SIZE,
	 FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS|FTF_BOOTCPUID},
	{3, 1, FDT_V3_SIZE,
	 FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS|FTF_BOOTCPUID|FTF_STRTABSIZE},
	{16, 16, FDT_V3_SIZE,
	 FTF_BOOTCPUID|FTF_STRTABSIZE|FTF_NOPS},
	{17, 16, FDT_V17_SIZE,
	 FTF_BOOTCPUID|FTF_STRTABSIZE|FTF_STRUCTSIZE|FTF_NOPS},
};

struct emitter {
	void (*cell)(void *, cell_t);
52
	void (*string)(void *, const char *, int);
53 54
	void (*align)(void *, int);
	void (*data)(void *, struct data);
55 56 57
	void (*beginnode)(void *, struct label *labels);
	void (*endnode)(void *, struct label *labels);
	void (*property)(void *, struct label *labels);
58 59 60 61 62 63 64 65 66
};

static void bin_emit_cell(void *e, cell_t val)
{
	struct data *dtbuf = e;

	*dtbuf = data_append_cell(*dtbuf, val);
}

67
static void bin_emit_string(void *e, const char *str, int len)
68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91
{
	struct data *dtbuf = e;

	if (len == 0)
		len = strlen(str);

	*dtbuf = data_append_data(*dtbuf, str, len);
	*dtbuf = data_append_byte(*dtbuf, '\0');
}

static void bin_emit_align(void *e, int a)
{
	struct data *dtbuf = e;

	*dtbuf = data_append_align(*dtbuf, a);
}

static void bin_emit_data(void *e, struct data d)
{
	struct data *dtbuf = e;

	*dtbuf = data_append_data(*dtbuf, d.val, d.len);
}

92
static void bin_emit_beginnode(void *e, struct label *labels)
93 94 95 96
{
	bin_emit_cell(e, FDT_BEGIN_NODE);
}

97
static void bin_emit_endnode(void *e, struct label *labels)
98 99 100 101
{
	bin_emit_cell(e, FDT_END_NODE);
}

102
static void bin_emit_property(void *e, struct label *labels)
103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129
{
	bin_emit_cell(e, FDT_PROP);
}

static struct emitter bin_emitter = {
	.cell = bin_emit_cell,
	.string = bin_emit_string,
	.align = bin_emit_align,
	.data = bin_emit_data,
	.beginnode = bin_emit_beginnode,
	.endnode = bin_emit_endnode,
	.property = bin_emit_property,
};

static void emit_label(FILE *f, const char *prefix, const char *label)
{
	fprintf(f, "\t.globl\t%s_%s\n", prefix, label);
	fprintf(f, "%s_%s:\n", prefix, label);
	fprintf(f, "_%s_%s:\n", prefix, label);
}

static void emit_offset_label(FILE *f, const char *label, int offset)
{
	fprintf(f, "\t.globl\t%s\n", label);
	fprintf(f, "%s\t= . + %d\n", label, offset);
}

130 131 132 133 134 135 136 137
#define ASM_EMIT_BELONG(f, fmt, ...) \
	{ \
		fprintf((f), "\t.byte\t((" fmt ") >> 24) & 0xff\n", __VA_ARGS__); \
		fprintf((f), "\t.byte\t((" fmt ") >> 16) & 0xff\n", __VA_ARGS__); \
		fprintf((f), "\t.byte\t((" fmt ") >> 8) & 0xff\n", __VA_ARGS__); \
		fprintf((f), "\t.byte\t(" fmt ") & 0xff\n", __VA_ARGS__); \
	}

138 139 140 141
static void asm_emit_cell(void *e, cell_t val)
{
	FILE *f = e;

142 143 144
	fprintf(f, "\t.byte 0x%02x; .byte 0x%02x; .byte 0x%02x; .byte 0x%02x\n",
		(val >> 24) & 0xff, (val >> 16) & 0xff,
		(val >> 8) & 0xff, val & 0xff);
145 146
}

147
static void asm_emit_string(void *e, const char *str, int len)
148 149 150
{
	FILE *f = e;

151 152 153 154
	if (len != 0)
		fprintf(f, "\t.string\t\"%.*s\"\n", len, str);
	else
		fprintf(f, "\t.string\t\"%s\"\n", str);
155 156 157 158 159 160
}

static void asm_emit_align(void *e, int a)
{
	FILE *f = e;

161
	fprintf(f, "\t.balign\t%d, 0\n", a);
162 163 164 165 166 167
}

static void asm_emit_data(void *e, struct data d)
{
	FILE *f = e;
	int off = 0;
168
	struct marker *m = d.markers;
169

170 171
	for_each_marker_of_type(m, LABEL)
		emit_offset_label(f, m->ref, m->offset);
172

173
	while ((d.len - off) >= sizeof(uint32_t)) {
174
		asm_emit_cell(e, fdt32_to_cpu(*((fdt32_t *)(d.val+off))));
175
		off += sizeof(uint32_t);
176 177
	}

178
	while ((d.len - off) >= 1) {
179 180 181 182 183 184 185
		fprintf(f, "\t.byte\t0x%hhx\n", d.val[off]);
		off += 1;
	}

	assert(off == d.len);
}

186
static void asm_emit_beginnode(void *e, struct label *labels)
187 188
{
	FILE *f = e;
189
	struct label *l;
190

191 192 193
	for_each_label(labels, l) {
		fprintf(f, "\t.globl\t%s\n", l->label);
		fprintf(f, "%s:\n", l->label);
194
	}
195 196
	fprintf(f, "\t/* FDT_BEGIN_NODE */\n");
	asm_emit_cell(e, FDT_BEGIN_NODE);
197 198
}

199
static void asm_emit_endnode(void *e, struct label *labels)
200 201
{
	FILE *f = e;
202
	struct label *l;
203

204 205 206 207 208
	fprintf(f, "\t/* FDT_END_NODE */\n");
	asm_emit_cell(e, FDT_END_NODE);
	for_each_label(labels, l) {
		fprintf(f, "\t.globl\t%s_end\n", l->label);
		fprintf(f, "%s_end:\n", l->label);
209 210 211
	}
}

212
static void asm_emit_property(void *e, struct label *labels)
213 214
{
	FILE *f = e;
215
	struct label *l;
216

217 218 219
	for_each_label(labels, l) {
		fprintf(f, "\t.globl\t%s\n", l->label);
		fprintf(f, "%s:\n", l->label);
220
	}
221 222
	fprintf(f, "\t/* FDT_PROP */\n");
	asm_emit_cell(e, FDT_PROP);
223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255
}

static struct emitter asm_emitter = {
	.cell = asm_emit_cell,
	.string = asm_emit_string,
	.align = asm_emit_align,
	.data = asm_emit_data,
	.beginnode = asm_emit_beginnode,
	.endnode = asm_emit_endnode,
	.property = asm_emit_property,
};

static int stringtable_insert(struct data *d, const char *str)
{
	int i;

	/* FIXME: do this more efficiently? */

	for (i = 0; i < d->len; i++) {
		if (streq(str, d->val + i))
			return i;
	}

	*d = data_append_data(*d, str, strlen(str)+1);
	return i;
}

static void flatten_tree(struct node *tree, struct emitter *emit,
			 void *etarget, struct data *strbuf,
			 struct version_info *vi)
{
	struct property *prop;
	struct node *child;
256
	bool seen_name_prop = false;
257

258 259 260
	if (tree->deleted)
		return;

261
	emit->beginnode(etarget, tree->labels);
262 263 264 265 266 267 268 269 270 271 272 273

	if (vi->flags & FTF_FULLPATH)
		emit->string(etarget, tree->fullpath, 0);
	else
		emit->string(etarget, tree->name, 0);

	emit->align(etarget, sizeof(cell_t));

	for_each_property(tree, prop) {
		int nameoff;

		if (streq(prop->name, "name"))
274
			seen_name_prop = true;
275 276 277

		nameoff = stringtable_insert(strbuf, prop->name);

278
		emit->property(etarget, prop->labels);
279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304
		emit->cell(etarget, prop->val.len);
		emit->cell(etarget, nameoff);

		if ((vi->flags & FTF_VARALIGN) && (prop->val.len >= 8))
			emit->align(etarget, 8);

		emit->data(etarget, prop->val);
		emit->align(etarget, sizeof(cell_t));
	}

	if ((vi->flags & FTF_NAMEPROPS) && !seen_name_prop) {
		emit->property(etarget, NULL);
		emit->cell(etarget, tree->basenamelen+1);
		emit->cell(etarget, stringtable_insert(strbuf, "name"));

		if ((vi->flags & FTF_VARALIGN) && ((tree->basenamelen+1) >= 8))
			emit->align(etarget, 8);

		emit->string(etarget, tree->name, tree->basenamelen);
		emit->align(etarget, sizeof(cell_t));
	}

	for_each_child(tree, child) {
		flatten_tree(child, emit, etarget, strbuf, vi);
	}

305
	emit->endnode(etarget, tree->labels);
306 307 308 309 310 311 312 313 314 315
}

static struct data flatten_reserve_list(struct reserve_info *reservelist,
				 struct version_info *vi)
{
	struct reserve_info *re;
	struct data d = empty_data;
	int    j;

	for (re = reservelist; re; re = re->next) {
316
		d = data_append_re(d, re->address, re->size);
317 318 319 320 321
	}
	/*
	 * Add additional reserved slots if the user asked for them.
	 */
	for (j = 0; j < reservenum; j++) {
322
		d = data_append_re(d, 0, 0);
323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338
	}

	return d;
}

static void make_fdt_header(struct fdt_header *fdt,
			    struct version_info *vi,
			    int reservesize, int dtsize, int strsize,
			    int boot_cpuid_phys)
{
	int reserve_off;

	reservesize += sizeof(struct fdt_reserve_entry);

	memset(fdt, 0xff, sizeof(*fdt));

339 340 341
	fdt->magic = cpu_to_fdt32(FDT_MAGIC);
	fdt->version = cpu_to_fdt32(vi->version);
	fdt->last_comp_version = cpu_to_fdt32(vi->last_comp_version);
342 343 344 345

	/* Reserve map should be doubleword aligned */
	reserve_off = ALIGN(vi->hdr_size, 8);

346 347 348
	fdt->off_mem_rsvmap = cpu_to_fdt32(reserve_off);
	fdt->off_dt_struct = cpu_to_fdt32(reserve_off + reservesize);
	fdt->off_dt_strings = cpu_to_fdt32(reserve_off + reservesize
349
					  + dtsize);
350
	fdt->totalsize = cpu_to_fdt32(reserve_off + reservesize + dtsize + strsize);
351 352

	if (vi->flags & FTF_BOOTCPUID)
353
		fdt->boot_cpuid_phys = cpu_to_fdt32(boot_cpuid_phys);
354
	if (vi->flags & FTF_STRTABSIZE)
355
		fdt->size_dt_strings = cpu_to_fdt32(strsize);
356
	if (vi->flags & FTF_STRUCTSIZE)
357
		fdt->size_dt_struct = cpu_to_fdt32(dtsize);
358 359
}

360
void dt_to_blob(FILE *f, struct dt_info *dti, int version)
361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377
{
	struct version_info *vi = NULL;
	int i;
	struct data blob       = empty_data;
	struct data reservebuf = empty_data;
	struct data dtbuf      = empty_data;
	struct data strbuf     = empty_data;
	struct fdt_header fdt;
	int padlen = 0;

	for (i = 0; i < ARRAY_SIZE(version_table); i++) {
		if (version_table[i].version == version)
			vi = &version_table[i];
	}
	if (!vi)
		die("Unknown device tree blob version %d\n", version);

378
	flatten_tree(dti->dt, &bin_emitter, &dtbuf, &strbuf, vi);
379 380
	bin_emit_cell(&dtbuf, FDT_END);

381
	reservebuf = flatten_reserve_list(dti->reservelist, vi);
382 383 384

	/* Make header */
	make_fdt_header(&fdt, vi, reservebuf.len, dtbuf.len, strbuf.len,
385
			dti->boot_cpuid_phys);
386 387 388 389 390

	/*
	 * If the user asked for more space than is used, adjust the totalsize.
	 */
	if (minsize > 0) {
391
		padlen = minsize - fdt32_to_cpu(fdt.totalsize);
392 393 394 395 396 397 398
		if (padlen < 0) {
			padlen = 0;
			if (quiet < 1)
				fprintf(stderr,
					"Warning: blob size %d >= minimum size %d\n",
					fdt32_to_cpu(fdt.totalsize), minsize);
		}
399 400 401 402 403
	}

	if (padsize > 0)
		padlen = padsize;

404 405 406 407
	if (alignsize > 0)
		padlen = ALIGN(fdt32_to_cpu(fdt.totalsize) + padlen, alignsize)
			- fdt32_to_cpu(fdt.totalsize);

408
	if (padlen > 0) {
409
		int tsize = fdt32_to_cpu(fdt.totalsize);
410
		tsize += padlen;
411
		fdt.totalsize = cpu_to_fdt32(tsize);
412 413 414 415 416 417 418
	}

	/*
	 * Assemble the blob: start with the header, add with alignment
	 * the reserve buffer, add the reserve map terminating zeroes,
	 * the device tree itself, and finally the strings.
	 */
419
	blob = data_append_data(blob, &fdt, vi->hdr_size);
420 421 422 423 424 425 426 427 428 429 430 431
	blob = data_append_align(blob, 8);
	blob = data_merge(blob, reservebuf);
	blob = data_append_zeroes(blob, sizeof(struct fdt_reserve_entry));
	blob = data_merge(blob, dtbuf);
	blob = data_merge(blob, strbuf);

	/*
	 * If the user asked for more space than is used, pad out the blob.
	 */
	if (padlen > 0)
		blob = data_append_zeroes(blob, padlen);

432 433 434 435 436 437 438
	if (fwrite(blob.val, blob.len, 1, f) != 1) {
		if (ferror(f))
			die("Error writing device tree blob: %s\n",
			    strerror(errno));
		else
			die("Short write on device tree blob\n");
	}
439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460

	/*
	 * data_merge() frees the right-hand element so only the blob
	 * remains to be freed.
	 */
	data_free(blob);
}

static void dump_stringtable_asm(FILE *f, struct data strbuf)
{
	const char *p;
	int len;

	p = strbuf.val;

	while (p < (strbuf.val + strbuf.len)) {
		len = strlen(p);
		fprintf(f, "\t.string \"%s\"\n", p);
		p += len+1;
	}
}

461
void dt_to_asm(FILE *f, struct dt_info *dti, int version)
462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479
{
	struct version_info *vi = NULL;
	int i;
	struct data strbuf = empty_data;
	struct reserve_info *re;
	const char *symprefix = "dt";

	for (i = 0; i < ARRAY_SIZE(version_table); i++) {
		if (version_table[i].version == version)
			vi = &version_table[i];
	}
	if (!vi)
		die("Unknown device tree blob version %d\n", version);

	fprintf(f, "/* autogenerated by dtc, do not edit */\n\n");

	emit_label(f, symprefix, "blob_start");
	emit_label(f, symprefix, "header");
480 481 482 483 484 485 486
	fprintf(f, "\t/* magic */\n");
	asm_emit_cell(f, FDT_MAGIC);
	fprintf(f, "\t/* totalsize */\n");
	ASM_EMIT_BELONG(f, "_%s_blob_abs_end - _%s_blob_start",
			symprefix, symprefix);
	fprintf(f, "\t/* off_dt_struct */\n");
	ASM_EMIT_BELONG(f, "_%s_struct_start - _%s_blob_start",
487
		symprefix, symprefix);
488 489
	fprintf(f, "\t/* off_dt_strings */\n");
	ASM_EMIT_BELONG(f, "_%s_strings_start - _%s_blob_start",
490
		symprefix, symprefix);
491 492
	fprintf(f, "\t/* off_mem_rsvmap */\n");
	ASM_EMIT_BELONG(f, "_%s_reserve_map - _%s_blob_start",
493
		symprefix, symprefix);
494 495 496 497 498 499 500
	fprintf(f, "\t/* version */\n");
	asm_emit_cell(f, vi->version);
	fprintf(f, "\t/* last_comp_version */\n");
	asm_emit_cell(f, vi->last_comp_version);

	if (vi->flags & FTF_BOOTCPUID) {
		fprintf(f, "\t/* boot_cpuid_phys */\n");
501
		asm_emit_cell(f, dti->boot_cpuid_phys);
502
	}
503

504 505 506 507 508
	if (vi->flags & FTF_STRTABSIZE) {
		fprintf(f, "\t/* size_dt_strings */\n");
		ASM_EMIT_BELONG(f, "_%s_strings_end - _%s_strings_start",
				symprefix, symprefix);
	}
509

510 511 512
	if (vi->flags & FTF_STRUCTSIZE) {
		fprintf(f, "\t/* size_dt_struct */\n");
		ASM_EMIT_BELONG(f, "_%s_struct_end - _%s_struct_start",
513
			symprefix, symprefix);
514
	}
515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530

	/*
	 * Reserve map entries.
	 * Align the reserve map to a doubleword boundary.
	 * Each entry is an (address, size) pair of u64 values.
	 * Always supply a zero-sized temination entry.
	 */
	asm_emit_align(f, 8);
	emit_label(f, symprefix, "reserve_map");

	fprintf(f, "/* Memory reserve map from source file */\n");

	/*
	 * Use .long on high and low halfs of u64s to avoid .quad
	 * as it appears .quad isn't available in some assemblers.
	 */
531
	for (re = dti->reservelist; re; re = re->next) {
532 533 534 535 536
		struct label *l;

		for_each_label(re->labels, l) {
			fprintf(f, "\t.globl\t%s\n", l->label);
			fprintf(f, "%s:\n", l->label);
537
		}
538
		ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->address >> 32));
539
		ASM_EMIT_BELONG(f, "0x%08x",
540 541 542
				(unsigned int)(re->address & 0xffffffff));
		ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->size >> 32));
		ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->size & 0xffffffff));
543 544 545 546 547 548 549 550
	}
	for (i = 0; i < reservenum; i++) {
		fprintf(f, "\t.long\t0, 0\n\t.long\t0, 0\n");
	}

	fprintf(f, "\t.long\t0, 0\n\t.long\t0, 0\n");

	emit_label(f, symprefix, "struct_start");
551
	flatten_tree(dti->dt, &asm_emitter, f, &strbuf, vi);
552 553 554

	fprintf(f, "\t/* FDT_END */\n");
	asm_emit_cell(f, FDT_END);
555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572
	emit_label(f, symprefix, "struct_end");

	emit_label(f, symprefix, "strings_start");
	dump_stringtable_asm(f, strbuf);
	emit_label(f, symprefix, "strings_end");

	emit_label(f, symprefix, "blob_end");

	/*
	 * If the user asked for more space than is used, pad it out.
	 */
	if (minsize > 0) {
		fprintf(f, "\t.space\t%d - (_%s_blob_end - _%s_blob_start), 0\n",
			minsize, symprefix, symprefix);
	}
	if (padsize > 0) {
		fprintf(f, "\t.space\t%d, 0\n", padsize);
	}
573 574
	if (alignsize > 0)
		asm_emit_align(f, alignsize);
575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600
	emit_label(f, symprefix, "blob_abs_end");

	data_free(strbuf);
}

struct inbuf {
	char *base, *limit, *ptr;
};

static void inbuf_init(struct inbuf *inb, void *base, void *limit)
{
	inb->base = base;
	inb->limit = limit;
	inb->ptr = inb->base;
}

static void flat_read_chunk(struct inbuf *inb, void *p, int len)
{
	if ((inb->ptr + len) > inb->limit)
		die("Premature end of data parsing flat device tree\n");

	memcpy(p, inb->ptr, len);

	inb->ptr += len;
}

601
static uint32_t flat_read_word(struct inbuf *inb)
602
{
603
	fdt32_t val;
604 605 606 607 608

	assert(((inb->ptr - inb->base) % sizeof(val)) == 0);

	flat_read_chunk(inb, &val, sizeof(val));

609
	return fdt32_to_cpu(val);
610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632
}

static void flat_realign(struct inbuf *inb, int align)
{
	int off = inb->ptr - inb->base;

	inb->ptr = inb->base + ALIGN(off, align);
	if (inb->ptr > inb->limit)
		die("Premature end of data parsing flat device tree\n");
}

static char *flat_read_string(struct inbuf *inb)
{
	int len = 0;
	const char *p = inb->ptr;
	char *str;

	do {
		if (p >= inb->limit)
			die("Premature end of data parsing flat device tree\n");
		len++;
	} while ((*p++) != '\0');

633
	str = xstrdup(inb->ptr);
634 635 636

	inb->ptr += len;

637
	flat_realign(inb, sizeof(uint32_t));
638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653

	return str;
}

static struct data flat_read_data(struct inbuf *inb, int len)
{
	struct data d = empty_data;

	if (len == 0)
		return empty_data;

	d = data_grow_for(d, len);
	d.len = len;

	flat_read_chunk(inb, d.val, len);

654
	flat_realign(inb, sizeof(uint32_t));
655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674

	return d;
}

static char *flat_read_stringtable(struct inbuf *inb, int offset)
{
	const char *p;

	p = inb->base + offset;
	while (1) {
		if (p >= inb->limit || p < inb->base)
			die("String offset %d overruns string table\n",
			    offset);

		if (*p == '\0')
			break;

		p++;
	}

675
	return xstrdup(inb->base + offset);
676 677 678 679 680
}

static struct property *flat_read_property(struct inbuf *dtbuf,
					   struct inbuf *strbuf, int flags)
{
681
	uint32_t proplen, stroff;
682 683 684 685 686 687 688 689 690 691 692 693 694
	char *name;
	struct data val;

	proplen = flat_read_word(dtbuf);
	stroff = flat_read_word(dtbuf);

	name = flat_read_stringtable(strbuf, stroff);

	if ((flags & FTF_VARALIGN) && (proplen >= 8))
		flat_realign(dtbuf, 8);

	val = flat_read_data(dtbuf, proplen);

695
	return build_property(name, val);
696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711
}


static struct reserve_info *flat_read_mem_reserve(struct inbuf *inb)
{
	struct reserve_info *reservelist = NULL;
	struct reserve_info *new;
	struct fdt_reserve_entry re;

	/*
	 * Each entry is a pair of u64 (addr, size) values for 4 cell_t's.
	 * List terminates at an entry with size equal to zero.
	 *
	 * First pass, count entries.
	 */
	while (1) {
712 713
		uint64_t address, size;

714
		flat_read_chunk(inb, &re, sizeof(re));
715 716 717
		address  = fdt64_to_cpu(re.address);
		size = fdt64_to_cpu(re.size);
		if (size == 0)
718 719
			break;

720
		new = build_reserve_entry(address, size);
721 722 723 724 725 726 727 728 729 730 731
		reservelist = add_reserve_entry(reservelist, new);
	}

	return reservelist;
}


static char *nodename_from_path(const char *ppath, const char *cpath)
{
	int plen;

732
	plen = strlen(ppath);
733

734
	if (!strstarts(cpath, ppath))
735 736
		die("Path \"%s\" is not valid as a child of \"%s\"\n",
		    cpath, ppath);
737

738 739 740
	/* root node is a special case */
	if (!streq(ppath, "/"))
		plen++;
741

742
	return xstrdup(cpath + plen);
743 744 745 746
}

static struct node *unflatten_tree(struct inbuf *dtbuf,
				   struct inbuf *strbuf,
747
				   const char *parent_flatname, int flags)
748 749
{
	struct node *node;
750 751
	char *flatname;
	uint32_t val;
752 753 754

	node = build_node(NULL, NULL);

755
	flatname = flat_read_string(dtbuf);
756

757 758 759 760
	if (flags & FTF_FULLPATH)
		node->name = nodename_from_path(parent_flatname, flatname);
	else
		node->name = flatname;
761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776

	do {
		struct property *prop;
		struct node *child;

		val = flat_read_word(dtbuf);
		switch (val) {
		case FDT_PROP:
			if (node->children)
				fprintf(stderr, "Warning: Flat tree input has "
					"subnodes preceding a property.\n");
			prop = flat_read_property(dtbuf, strbuf, flags);
			add_property(node, prop);
			break;

		case FDT_BEGIN_NODE:
777
			child = unflatten_tree(dtbuf,strbuf, flatname, flags);
778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801
			add_child(node, child);
			break;

		case FDT_END_NODE:
			break;

		case FDT_END:
			die("Premature FDT_END in device tree blob\n");
			break;

		case FDT_NOP:
			if (!(flags & FTF_NOPS))
				fprintf(stderr, "Warning: NOP tag found in flat tree"
					" version <16\n");

			/* Ignore */
			break;

		default:
			die("Invalid opcode word %08x in device tree blob\n",
			    val);
		}
	} while (val != FDT_END_NODE);

802 803 804 805
	if (node->name != flatname) {
		free(flatname);
	}

806 807 808 809
	return node;
}


810
struct dt_info *dt_from_blob(const char *fname)
811
{
812
	FILE *f;
813
	fdt32_t magic_buf, totalsize_buf;
814 815
	uint32_t magic, totalsize, version, size_dt, boot_cpuid_phys;
	uint32_t off_dt, off_str, off_mem_rsvmap;
816 817 818 819 820 821 822 823 824
	int rc;
	char *blob;
	struct fdt_header *fdt;
	char *p;
	struct inbuf dtbuf, strbuf;
	struct inbuf memresvbuf;
	int sizeleft;
	struct reserve_info *reservelist;
	struct node *tree;
825
	uint32_t val;
826 827
	int flags = 0;

828
	f = srcfile_relative_open(fname, NULL);
829

830
	rc = fread(&magic_buf, sizeof(magic_buf), 1, f);
831
	if (ferror(f))
832 833 834
		die("Error reading DT blob magic number: %s\n",
		    strerror(errno));
	if (rc < 1) {
835
		if (feof(f))
836 837 838 839 840
			die("EOF reading DT blob magic number\n");
		else
			die("Mysterious short read reading magic number\n");
	}

841
	magic = fdt32_to_cpu(magic_buf);
842 843 844
	if (magic != FDT_MAGIC)
		die("Blob has incorrect magic number\n");

845
	rc = fread(&totalsize_buf, sizeof(totalsize_buf), 1, f);
846
	if (ferror(f))
847 848
		die("Error reading DT blob size: %s\n", strerror(errno));
	if (rc < 1) {
849
		if (feof(f))
850 851 852 853 854
			die("EOF reading DT blob size\n");
		else
			die("Mysterious short read reading blob size\n");
	}

855
	totalsize = fdt32_to_cpu(totalsize_buf);
856 857 858 859 860 861
	if (totalsize < FDT_V1_SIZE)
		die("DT blob size (%d) is too small\n", totalsize);

	blob = xmalloc(totalsize);

	fdt = (struct fdt_header *)blob;
862 863
	fdt->magic = cpu_to_fdt32(magic);
	fdt->totalsize = cpu_to_fdt32(totalsize);
864 865 866 867 868

	sizeleft = totalsize - sizeof(magic) - sizeof(totalsize);
	p = blob + sizeof(magic)  + sizeof(totalsize);

	while (sizeleft) {
869
		if (feof(f))
870 871 872
			die("EOF before reading %d bytes of DT blob\n",
			    totalsize);

873 874
		rc = fread(p, 1, sizeleft, f);
		if (ferror(f))
875 876 877 878 879 880 881
			die("Error reading DT blob: %s\n",
			    strerror(errno));

		sizeleft -= rc;
		p += rc;
	}

882 883 884 885 886
	off_dt = fdt32_to_cpu(fdt->off_dt_struct);
	off_str = fdt32_to_cpu(fdt->off_dt_strings);
	off_mem_rsvmap = fdt32_to_cpu(fdt->off_mem_rsvmap);
	version = fdt32_to_cpu(fdt->version);
	boot_cpuid_phys = fdt32_to_cpu(fdt->boot_cpuid_phys);
887 888 889 890 891 892 893 894 895 896 897

	if (off_mem_rsvmap >= totalsize)
		die("Mem Reserve structure offset exceeds total size\n");

	if (off_dt >= totalsize)
		die("DT structure offset exceeds total size\n");

	if (off_str > totalsize)
		die("String table offset exceeds total size\n");

	if (version >= 3) {
898
		uint32_t size_str = fdt32_to_cpu(fdt->size_dt_strings);
899
		if ((off_str+size_str < off_str) || (off_str+size_str > totalsize))
900
			die("String table extends past total size\n");
901 902 903
		inbuf_init(&strbuf, blob + off_str, blob + off_str + size_str);
	} else {
		inbuf_init(&strbuf, blob + off_str, blob + totalsize);
904 905 906
	}

	if (version >= 17) {
907
		size_dt = fdt32_to_cpu(fdt->size_dt_struct);
908
		if ((off_dt+size_dt < off_dt) || (off_dt+size_dt > totalsize))
909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936
			die("Structure block extends past total size\n");
	}

	if (version < 16) {
		flags |= FTF_FULLPATH | FTF_NAMEPROPS | FTF_VARALIGN;
	} else {
		flags |= FTF_NOPS;
	}

	inbuf_init(&memresvbuf,
		   blob + off_mem_rsvmap, blob + totalsize);
	inbuf_init(&dtbuf, blob + off_dt, blob + totalsize);

	reservelist = flat_read_mem_reserve(&memresvbuf);

	val = flat_read_word(&dtbuf);

	if (val != FDT_BEGIN_NODE)
		die("Device tree blob doesn't begin with FDT_BEGIN_NODE (begins with 0x%08x)\n", val);

	tree = unflatten_tree(&dtbuf, &strbuf, "", flags);

	val = flat_read_word(&dtbuf);
	if (val != FDT_END)
		die("Device tree blob doesn't end with FDT_END\n");

	free(blob);

937
	fclose(f);
938

939
	return build_dt_info(DTSF_V1, reservelist, tree, boot_cpuid_phys);
940
}