flattree.c revision 267654
1/*
2 * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
3 *
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation; either version 2 of the
8 * License, or (at your option) any later version.
9 *
10 *  This program is distributed in the hope that it will be useful,
11 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13 *  General Public License for more details.
14 *
15 *  You should have received a copy of the GNU General Public License
16 *  along with this program; if not, write to the Free Software
17 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
18 *                                                                   USA
19 */
20
21#include "dtc.h"
22#include "srcpos.h"
23
24#define FTF_FULLPATH	0x1
25#define FTF_VARALIGN	0x2
26#define FTF_NAMEPROPS	0x4
27#define FTF_BOOTCPUID	0x8
28#define FTF_STRTABSIZE	0x10
29#define FTF_STRUCTSIZE	0x20
30#define FTF_NOPS	0x40
31
32static struct version_info {
33	int version;
34	int last_comp_version;
35	int hdr_size;
36	int flags;
37} version_table[] = {
38	{1, 1, FDT_V1_SIZE,
39	 FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS},
40	{2, 1, FDT_V2_SIZE,
41	 FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS|FTF_BOOTCPUID},
42	{3, 1, FDT_V3_SIZE,
43	 FTF_FULLPATH|FTF_VARALIGN|FTF_NAMEPROPS|FTF_BOOTCPUID|FTF_STRTABSIZE},
44	{16, 16, FDT_V3_SIZE,
45	 FTF_BOOTCPUID|FTF_STRTABSIZE|FTF_NOPS},
46	{17, 16, FDT_V17_SIZE,
47	 FTF_BOOTCPUID|FTF_STRTABSIZE|FTF_STRUCTSIZE|FTF_NOPS},
48};
49
50struct emitter {
51	void (*cell)(void *, cell_t);
52	void (*string)(void *, char *, int);
53	void (*align)(void *, int);
54	void (*data)(void *, struct data);
55	void (*beginnode)(void *, const char *);
56	void (*endnode)(void *, const char *);
57	void (*property)(void *, const char *);
58};
59
60static void bin_emit_cell(void *e, cell_t val)
61{
62	struct data *dtbuf = e;
63
64	*dtbuf = data_append_cell(*dtbuf, val);
65}
66
67static void bin_emit_string(void *e, char *str, int len)
68{
69	struct data *dtbuf = e;
70
71	if (len == 0)
72		len = strlen(str);
73
74	*dtbuf = data_append_data(*dtbuf, str, len);
75	*dtbuf = data_append_byte(*dtbuf, '\0');
76}
77
78static void bin_emit_align(void *e, int a)
79{
80	struct data *dtbuf = e;
81
82	*dtbuf = data_append_align(*dtbuf, a);
83}
84
85static void bin_emit_data(void *e, struct data d)
86{
87	struct data *dtbuf = e;
88
89	*dtbuf = data_append_data(*dtbuf, d.val, d.len);
90}
91
92static void bin_emit_beginnode(void *e, const char *label)
93{
94	bin_emit_cell(e, FDT_BEGIN_NODE);
95}
96
97static void bin_emit_endnode(void *e, const char *label)
98{
99	bin_emit_cell(e, FDT_END_NODE);
100}
101
102static void bin_emit_property(void *e, const char *label)
103{
104	bin_emit_cell(e, FDT_PROP);
105}
106
107static struct emitter bin_emitter = {
108	.cell = bin_emit_cell,
109	.string = bin_emit_string,
110	.align = bin_emit_align,
111	.data = bin_emit_data,
112	.beginnode = bin_emit_beginnode,
113	.endnode = bin_emit_endnode,
114	.property = bin_emit_property,
115};
116
117static void emit_label(FILE *f, const char *prefix, const char *label)
118{
119	fprintf(f, "\t.globl\t%s_%s\n", prefix, label);
120	fprintf(f, "%s_%s:\n", prefix, label);
121	fprintf(f, "_%s_%s:\n", prefix, label);
122}
123
124static void emit_offset_label(FILE *f, const char *label, int offset)
125{
126	fprintf(f, "\t.globl\t%s\n", label);
127	fprintf(f, "%s\t= . + %d\n", label, offset);
128}
129
130#define ASM_EMIT_BELONG(f, fmt, ...) \
131	{ \
132		fprintf((f), "\t.byte\t((" fmt ") >> 24) & 0xff\n", __VA_ARGS__); \
133		fprintf((f), "\t.byte\t((" fmt ") >> 16) & 0xff\n", __VA_ARGS__); \
134		fprintf((f), "\t.byte\t((" fmt ") >> 8) & 0xff\n", __VA_ARGS__); \
135		fprintf((f), "\t.byte\t(" fmt ") & 0xff\n", __VA_ARGS__); \
136	}
137
138static void asm_emit_cell(void *e, cell_t val)
139{
140	FILE *f = e;
141
142	fprintf(f, "\t.byte 0x%02x; .byte 0x%02x; .byte 0x%02x; .byte 0x%02x\n",
143		(val >> 24) & 0xff, (val >> 16) & 0xff,
144		(val >> 8) & 0xff, val & 0xff);
145}
146
147static void asm_emit_string(void *e, char *str, int len)
148{
149	FILE *f = e;
150	char c = 0;
151
152	if (len != 0) {
153		/* XXX: ewww */
154		c = str[len];
155		str[len] = '\0';
156	}
157
158	fprintf(f, "\t.string\t\"%s\"\n", str);
159
160	if (len != 0) {
161		str[len] = c;
162	}
163}
164
165static void asm_emit_align(void *e, int a)
166{
167	FILE *f = e;
168
169	fprintf(f, "\t.balign\t%d, 0\n", a);
170}
171
172static void asm_emit_data(void *e, struct data d)
173{
174	FILE *f = e;
175	int off = 0;
176	struct marker *m = d.markers;
177
178	for_each_marker_of_type(m, LABEL)
179		emit_offset_label(f, m->ref, m->offset);
180
181	while ((d.len - off) >= sizeof(uint32_t)) {
182		asm_emit_cell(e, fdt32_to_cpu(*((uint32_t *)(d.val+off))));
183		off += sizeof(uint32_t);
184	}
185
186	while ((d.len - off) >= 1) {
187		fprintf(f, "\t.byte\t0x%hhx\n", d.val[off]);
188		off += 1;
189	}
190
191	assert(off == d.len);
192}
193
194static void asm_emit_beginnode(void *e, const char *label)
195{
196	FILE *f = e;
197
198	if (label) {
199		fprintf(f, "\t.globl\t%s\n", label);
200		fprintf(f, "%s:\n", label);
201	}
202	fprintf(f, "\t/* FDT_BEGIN_NODE */\n");
203	asm_emit_cell(e, FDT_BEGIN_NODE);
204}
205
206static void asm_emit_endnode(void *e, const char *label)
207{
208	FILE *f = e;
209
210	fprintf(f, "\t/* FDT_END_NODE */\n");
211	asm_emit_cell(e, FDT_END_NODE);
212	if (label) {
213		fprintf(f, "\t.globl\t%s_end\n", label);
214		fprintf(f, "%s_end:\n", label);
215	}
216}
217
218static void asm_emit_property(void *e, const char *label)
219{
220	FILE *f = e;
221
222	if (label) {
223		fprintf(f, "\t.globl\t%s\n", label);
224		fprintf(f, "%s:\n", label);
225	}
226	fprintf(f, "\t/* FDT_PROP */\n");
227	asm_emit_cell(e, FDT_PROP);
228}
229
230static struct emitter asm_emitter = {
231	.cell = asm_emit_cell,
232	.string = asm_emit_string,
233	.align = asm_emit_align,
234	.data = asm_emit_data,
235	.beginnode = asm_emit_beginnode,
236	.endnode = asm_emit_endnode,
237	.property = asm_emit_property,
238};
239
240static int stringtable_insert(struct data *d, const char *str)
241{
242	int i;
243
244	/* FIXME: do this more efficiently? */
245
246	for (i = 0; i < d->len; i++) {
247		if (streq(str, d->val + i))
248			return i;
249	}
250
251	*d = data_append_data(*d, str, strlen(str)+1);
252	return i;
253}
254
255static void flatten_tree(struct node *tree, struct emitter *emit,
256			 void *etarget, struct data *strbuf,
257			 struct version_info *vi)
258{
259	struct property *prop;
260	struct node *child;
261	int seen_name_prop = 0;
262
263	emit->beginnode(etarget, tree->label);
264
265	if (vi->flags & FTF_FULLPATH)
266		emit->string(etarget, tree->fullpath, 0);
267	else
268		emit->string(etarget, tree->name, 0);
269
270	emit->align(etarget, sizeof(cell_t));
271
272	for_each_property(tree, prop) {
273		int nameoff;
274
275		if (streq(prop->name, "name"))
276			seen_name_prop = 1;
277
278		nameoff = stringtable_insert(strbuf, prop->name);
279
280		emit->property(etarget, prop->label);
281		emit->cell(etarget, prop->val.len);
282		emit->cell(etarget, nameoff);
283
284		if ((vi->flags & FTF_VARALIGN) && (prop->val.len >= 8))
285			emit->align(etarget, 8);
286
287		emit->data(etarget, prop->val);
288		emit->align(etarget, sizeof(cell_t));
289	}
290
291	if ((vi->flags & FTF_NAMEPROPS) && !seen_name_prop) {
292		emit->property(etarget, NULL);
293		emit->cell(etarget, tree->basenamelen+1);
294		emit->cell(etarget, stringtable_insert(strbuf, "name"));
295
296		if ((vi->flags & FTF_VARALIGN) && ((tree->basenamelen+1) >= 8))
297			emit->align(etarget, 8);
298
299		emit->string(etarget, tree->name, tree->basenamelen);
300		emit->align(etarget, sizeof(cell_t));
301	}
302
303	for_each_child(tree, child) {
304		flatten_tree(child, emit, etarget, strbuf, vi);
305	}
306
307	emit->endnode(etarget, tree->label);
308}
309
310static struct data flatten_reserve_list(struct reserve_info *reservelist,
311				 struct version_info *vi)
312{
313	struct reserve_info *re;
314	struct data d = empty_data;
315	static struct fdt_reserve_entry null_re = {0,0};
316	int    j;
317
318	for (re = reservelist; re; re = re->next) {
319		d = data_append_re(d, &re->re);
320	}
321	/*
322	 * Add additional reserved slots if the user asked for them.
323	 */
324	for (j = 0; j < reservenum; j++) {
325		d = data_append_re(d, &null_re);
326	}
327
328	return d;
329}
330
331static void make_fdt_header(struct fdt_header *fdt,
332			    struct version_info *vi,
333			    int reservesize, int dtsize, int strsize,
334			    int boot_cpuid_phys)
335{
336	int reserve_off;
337
338	reservesize += sizeof(struct fdt_reserve_entry);
339
340	memset(fdt, 0xff, sizeof(*fdt));
341
342	fdt->magic = cpu_to_fdt32(FDT_MAGIC);
343	fdt->version = cpu_to_fdt32(vi->version);
344	fdt->last_comp_version = cpu_to_fdt32(vi->last_comp_version);
345
346	/* Reserve map should be doubleword aligned */
347	reserve_off = ALIGN(vi->hdr_size, 8);
348
349	fdt->off_mem_rsvmap = cpu_to_fdt32(reserve_off);
350	fdt->off_dt_struct = cpu_to_fdt32(reserve_off + reservesize);
351	fdt->off_dt_strings = cpu_to_fdt32(reserve_off + reservesize
352					  + dtsize);
353	fdt->totalsize = cpu_to_fdt32(reserve_off + reservesize + dtsize + strsize);
354
355	if (vi->flags & FTF_BOOTCPUID)
356		fdt->boot_cpuid_phys = cpu_to_fdt32(boot_cpuid_phys);
357	if (vi->flags & FTF_STRTABSIZE)
358		fdt->size_dt_strings = cpu_to_fdt32(strsize);
359	if (vi->flags & FTF_STRUCTSIZE)
360		fdt->size_dt_struct = cpu_to_fdt32(dtsize);
361}
362
363void dt_to_blob(FILE *f, struct boot_info *bi, int version)
364{
365	struct version_info *vi = NULL;
366	int i;
367	struct data blob       = empty_data;
368	struct data reservebuf = empty_data;
369	struct data dtbuf      = empty_data;
370	struct data strbuf     = empty_data;
371	struct fdt_header fdt;
372	int padlen = 0;
373
374	for (i = 0; i < ARRAY_SIZE(version_table); i++) {
375		if (version_table[i].version == version)
376			vi = &version_table[i];
377	}
378	if (!vi)
379		die("Unknown device tree blob version %d\n", version);
380
381	flatten_tree(bi->dt, &bin_emitter, &dtbuf, &strbuf, vi);
382	bin_emit_cell(&dtbuf, FDT_END);
383
384	reservebuf = flatten_reserve_list(bi->reservelist, vi);
385
386	/* Make header */
387	make_fdt_header(&fdt, vi, reservebuf.len, dtbuf.len, strbuf.len,
388			bi->boot_cpuid_phys);
389
390	/*
391	 * If the user asked for more space than is used, adjust the totalsize.
392	 */
393	if (minsize > 0) {
394		padlen = minsize - fdt32_to_cpu(fdt.totalsize);
395		if ((padlen < 0) && (quiet < 1))
396			fprintf(stderr,
397				"Warning: blob size %d >= minimum size %d\n",
398				fdt32_to_cpu(fdt.totalsize), minsize);
399	}
400
401	if (padsize > 0)
402		padlen = padsize;
403
404	if (padlen > 0) {
405		int tsize = fdt32_to_cpu(fdt.totalsize);
406		tsize += padlen;
407		fdt.totalsize = cpu_to_fdt32(tsize);
408	}
409
410	/*
411	 * Assemble the blob: start with the header, add with alignment
412	 * the reserve buffer, add the reserve map terminating zeroes,
413	 * the device tree itself, and finally the strings.
414	 */
415	blob = data_append_data(blob, &fdt, vi->hdr_size);
416	blob = data_append_align(blob, 8);
417	blob = data_merge(blob, reservebuf);
418	blob = data_append_zeroes(blob, sizeof(struct fdt_reserve_entry));
419	blob = data_merge(blob, dtbuf);
420	blob = data_merge(blob, strbuf);
421
422	/*
423	 * If the user asked for more space than is used, pad out the blob.
424	 */
425	if (padlen > 0)
426		blob = data_append_zeroes(blob, padlen);
427
428	if (fwrite(blob.val, blob.len, 1, f) != 1) {
429		if (ferror(f))
430			die("Error writing device tree blob: %s\n",
431			    strerror(errno));
432		else
433			die("Short write on device tree blob\n");
434	}
435
436	/*
437	 * data_merge() frees the right-hand element so only the blob
438	 * remains to be freed.
439	 */
440	data_free(blob);
441}
442
443static void dump_stringtable_asm(FILE *f, struct data strbuf)
444{
445	const char *p;
446	int len;
447
448	p = strbuf.val;
449
450	while (p < (strbuf.val + strbuf.len)) {
451		len = strlen(p);
452		fprintf(f, "\t.string \"%s\"\n", p);
453		p += len+1;
454	}
455}
456
457void dt_to_asm(FILE *f, struct boot_info *bi, int version)
458{
459	struct version_info *vi = NULL;
460	int i;
461	struct data strbuf = empty_data;
462	struct reserve_info *re;
463	const char *symprefix = "dt";
464
465	for (i = 0; i < ARRAY_SIZE(version_table); i++) {
466		if (version_table[i].version == version)
467			vi = &version_table[i];
468	}
469	if (!vi)
470		die("Unknown device tree blob version %d\n", version);
471
472	fprintf(f, "/* autogenerated by dtc, do not edit */\n\n");
473
474	emit_label(f, symprefix, "blob_start");
475	emit_label(f, symprefix, "header");
476	fprintf(f, "\t/* magic */\n");
477	asm_emit_cell(f, FDT_MAGIC);
478	fprintf(f, "\t/* totalsize */\n");
479	ASM_EMIT_BELONG(f, "_%s_blob_abs_end - _%s_blob_start",
480			symprefix, symprefix);
481	fprintf(f, "\t/* off_dt_struct */\n");
482	ASM_EMIT_BELONG(f, "_%s_struct_start - _%s_blob_start",
483		symprefix, symprefix);
484	fprintf(f, "\t/* off_dt_strings */\n");
485	ASM_EMIT_BELONG(f, "_%s_strings_start - _%s_blob_start",
486		symprefix, symprefix);
487	fprintf(f, "\t/* off_mem_rsvmap */\n");
488	ASM_EMIT_BELONG(f, "_%s_reserve_map - _%s_blob_start",
489		symprefix, symprefix);
490	fprintf(f, "\t/* version */\n");
491	asm_emit_cell(f, vi->version);
492	fprintf(f, "\t/* last_comp_version */\n");
493	asm_emit_cell(f, vi->last_comp_version);
494
495	if (vi->flags & FTF_BOOTCPUID) {
496		fprintf(f, "\t/* boot_cpuid_phys */\n");
497		asm_emit_cell(f, bi->boot_cpuid_phys);
498	}
499
500	if (vi->flags & FTF_STRTABSIZE) {
501		fprintf(f, "\t/* size_dt_strings */\n");
502		ASM_EMIT_BELONG(f, "_%s_strings_end - _%s_strings_start",
503				symprefix, symprefix);
504	}
505
506	if (vi->flags & FTF_STRUCTSIZE) {
507		fprintf(f, "\t/* size_dt_struct */\n");
508		ASM_EMIT_BELONG(f, "_%s_struct_end - _%s_struct_start",
509			symprefix, symprefix);
510	}
511
512	/*
513	 * Reserve map entries.
514	 * Align the reserve map to a doubleword boundary.
515	 * Each entry is an (address, size) pair of u64 values.
516	 * Always supply a zero-sized temination entry.
517	 */
518	asm_emit_align(f, 8);
519	emit_label(f, symprefix, "reserve_map");
520
521	fprintf(f, "/* Memory reserve map from source file */\n");
522
523	/*
524	 * Use .long on high and low halfs of u64s to avoid .quad
525	 * as it appears .quad isn't available in some assemblers.
526	 */
527	for (re = bi->reservelist; re; re = re->next) {
528		if (re->label) {
529			fprintf(f, "\t.globl\t%s\n", re->label);
530			fprintf(f, "%s:\n", re->label);
531		}
532		ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->re.address >> 32));
533		ASM_EMIT_BELONG(f, "0x%08x",
534				(unsigned int)(re->re.address & 0xffffffff));
535		ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->re.size >> 32));
536		ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->re.size & 0xffffffff));
537	}
538	for (i = 0; i < reservenum; i++) {
539		fprintf(f, "\t.long\t0, 0\n\t.long\t0, 0\n");
540	}
541
542	fprintf(f, "\t.long\t0, 0\n\t.long\t0, 0\n");
543
544	emit_label(f, symprefix, "struct_start");
545	flatten_tree(bi->dt, &asm_emitter, f, &strbuf, vi);
546
547	fprintf(f, "\t/* FDT_END */\n");
548	asm_emit_cell(f, FDT_END);
549	emit_label(f, symprefix, "struct_end");
550
551	emit_label(f, symprefix, "strings_start");
552	dump_stringtable_asm(f, strbuf);
553	emit_label(f, symprefix, "strings_end");
554
555	emit_label(f, symprefix, "blob_end");
556
557	/*
558	 * If the user asked for more space than is used, pad it out.
559	 */
560	if (minsize > 0) {
561		fprintf(f, "\t.space\t%d - (_%s_blob_end - _%s_blob_start), 0\n",
562			minsize, symprefix, symprefix);
563	}
564	if (padsize > 0) {
565		fprintf(f, "\t.space\t%d, 0\n", padsize);
566	}
567	emit_label(f, symprefix, "blob_abs_end");
568
569	data_free(strbuf);
570}
571
572struct inbuf {
573	char *base, *limit, *ptr;
574};
575
576static void inbuf_init(struct inbuf *inb, void *base, void *limit)
577{
578	inb->base = base;
579	inb->limit = limit;
580	inb->ptr = inb->base;
581}
582
583static void flat_read_chunk(struct inbuf *inb, void *p, int len)
584{
585	if ((inb->ptr + len) > inb->limit)
586		die("Premature end of data parsing flat device tree\n");
587
588	memcpy(p, inb->ptr, len);
589
590	inb->ptr += len;
591}
592
593static uint32_t flat_read_word(struct inbuf *inb)
594{
595	uint32_t val;
596
597	assert(((inb->ptr - inb->base) % sizeof(val)) == 0);
598
599	flat_read_chunk(inb, &val, sizeof(val));
600
601	return fdt32_to_cpu(val);
602}
603
604static void flat_realign(struct inbuf *inb, int align)
605{
606	int off = inb->ptr - inb->base;
607
608	inb->ptr = inb->base + ALIGN(off, align);
609	if (inb->ptr > inb->limit)
610		die("Premature end of data parsing flat device tree\n");
611}
612
613static char *flat_read_string(struct inbuf *inb)
614{
615	int len = 0;
616	const char *p = inb->ptr;
617	char *str;
618
619	do {
620		if (p >= inb->limit)
621			die("Premature end of data parsing flat device tree\n");
622		len++;
623	} while ((*p++) != '\0');
624
625	str = xstrdup(inb->ptr);
626
627	inb->ptr += len;
628
629	flat_realign(inb, sizeof(uint32_t));
630
631	return str;
632}
633
634static struct data flat_read_data(struct inbuf *inb, int len)
635{
636	struct data d = empty_data;
637
638	if (len == 0)
639		return empty_data;
640
641	d = data_grow_for(d, len);
642	d.len = len;
643
644	flat_read_chunk(inb, d.val, len);
645
646	flat_realign(inb, sizeof(uint32_t));
647
648	return d;
649}
650
651static char *flat_read_stringtable(struct inbuf *inb, int offset)
652{
653	const char *p;
654
655	p = inb->base + offset;
656	while (1) {
657		if (p >= inb->limit || p < inb->base)
658			die("String offset %d overruns string table\n",
659			    offset);
660
661		if (*p == '\0')
662			break;
663
664		p++;
665	}
666
667	return xstrdup(inb->base + offset);
668}
669
670static struct property *flat_read_property(struct inbuf *dtbuf,
671					   struct inbuf *strbuf, int flags)
672{
673	uint32_t proplen, stroff;
674	char *name;
675	struct data val;
676
677	proplen = flat_read_word(dtbuf);
678	stroff = flat_read_word(dtbuf);
679
680	name = flat_read_stringtable(strbuf, stroff);
681
682	if ((flags & FTF_VARALIGN) && (proplen >= 8))
683		flat_realign(dtbuf, 8);
684
685	val = flat_read_data(dtbuf, proplen);
686
687	return build_property(name, val, NULL);
688}
689
690
691static struct reserve_info *flat_read_mem_reserve(struct inbuf *inb)
692{
693	struct reserve_info *reservelist = NULL;
694	struct reserve_info *new;
695	const char *p;
696	struct fdt_reserve_entry re;
697
698	/*
699	 * Each entry is a pair of u64 (addr, size) values for 4 cell_t's.
700	 * List terminates at an entry with size equal to zero.
701	 *
702	 * First pass, count entries.
703	 */
704	p = inb->ptr;
705	while (1) {
706		flat_read_chunk(inb, &re, sizeof(re));
707		re.address  = fdt64_to_cpu(re.address);
708		re.size = fdt64_to_cpu(re.size);
709		if (re.size == 0)
710			break;
711
712		new = build_reserve_entry(re.address, re.size, NULL);
713		reservelist = add_reserve_entry(reservelist, new);
714	}
715
716	return reservelist;
717}
718
719
720static char *nodename_from_path(const char *ppath, const char *cpath)
721{
722	int plen;
723
724	plen = strlen(ppath);
725
726	if (!strneq(ppath, cpath, plen))
727		die("Path \"%s\" is not valid as a child of \"%s\"\n",
728		    cpath, ppath);
729
730	/* root node is a special case */
731	if (!streq(ppath, "/"))
732		plen++;
733
734	return xstrdup(cpath + plen);
735}
736
737static struct node *unflatten_tree(struct inbuf *dtbuf,
738				   struct inbuf *strbuf,
739				   const char *parent_flatname, int flags)
740{
741	struct node *node;
742	char *flatname;
743	uint32_t val;
744
745	node = build_node(NULL, NULL);
746
747	flatname = flat_read_string(dtbuf);
748
749	if (flags & FTF_FULLPATH)
750		node->name = nodename_from_path(parent_flatname, flatname);
751	else
752		node->name = flatname;
753
754	do {
755		struct property *prop;
756		struct node *child;
757
758		val = flat_read_word(dtbuf);
759		switch (val) {
760		case FDT_PROP:
761			if (node->children)
762				fprintf(stderr, "Warning: Flat tree input has "
763					"subnodes preceding a property.\n");
764			prop = flat_read_property(dtbuf, strbuf, flags);
765			add_property(node, prop);
766			break;
767
768		case FDT_BEGIN_NODE:
769			child = unflatten_tree(dtbuf,strbuf, flatname, flags);
770			add_child(node, child);
771			break;
772
773		case FDT_END_NODE:
774			break;
775
776		case FDT_END:
777			die("Premature FDT_END in device tree blob\n");
778			break;
779
780		case FDT_NOP:
781			if (!(flags & FTF_NOPS))
782				fprintf(stderr, "Warning: NOP tag found in flat tree"
783					" version <16\n");
784
785			/* Ignore */
786			break;
787
788		default:
789			die("Invalid opcode word %08x in device tree blob\n",
790			    val);
791		}
792	} while (val != FDT_END_NODE);
793
794	return node;
795}
796
797
798struct boot_info *dt_from_blob(const char *fname)
799{
800	struct dtc_file *dtcf;
801	uint32_t magic, totalsize, version, size_dt, boot_cpuid_phys;
802	uint32_t off_dt, off_str, off_mem_rsvmap;
803	int rc;
804	char *blob;
805	struct fdt_header *fdt;
806	char *p;
807	struct inbuf dtbuf, strbuf;
808	struct inbuf memresvbuf;
809	int sizeleft;
810	struct reserve_info *reservelist;
811	struct node *tree;
812	uint32_t val;
813	int flags = 0;
814
815	dtcf = dtc_open_file(fname, NULL);
816
817	rc = fread(&magic, sizeof(magic), 1, dtcf->file);
818	if (ferror(dtcf->file))
819		die("Error reading DT blob magic number: %s\n",
820		    strerror(errno));
821	if (rc < 1) {
822		if (feof(dtcf->file))
823			die("EOF reading DT blob magic number\n");
824		else
825			die("Mysterious short read reading magic number\n");
826	}
827
828	magic = fdt32_to_cpu(magic);
829	if (magic != FDT_MAGIC)
830		die("Blob has incorrect magic number\n");
831
832	rc = fread(&totalsize, sizeof(totalsize), 1, dtcf->file);
833	if (ferror(dtcf->file))
834		die("Error reading DT blob size: %s\n", strerror(errno));
835	if (rc < 1) {
836		if (feof(dtcf->file))
837			die("EOF reading DT blob size\n");
838		else
839			die("Mysterious short read reading blob size\n");
840	}
841
842	totalsize = fdt32_to_cpu(totalsize);
843	if (totalsize < FDT_V1_SIZE)
844		die("DT blob size (%d) is too small\n", totalsize);
845
846	blob = xmalloc(totalsize);
847
848	fdt = (struct fdt_header *)blob;
849	fdt->magic = cpu_to_fdt32(magic);
850	fdt->totalsize = cpu_to_fdt32(totalsize);
851
852	sizeleft = totalsize - sizeof(magic) - sizeof(totalsize);
853	p = blob + sizeof(magic)  + sizeof(totalsize);
854
855	while (sizeleft) {
856		if (feof(dtcf->file))
857			die("EOF before reading %d bytes of DT blob\n",
858			    totalsize);
859
860		rc = fread(p, 1, sizeleft, dtcf->file);
861		if (ferror(dtcf->file))
862			die("Error reading DT blob: %s\n",
863			    strerror(errno));
864
865		sizeleft -= rc;
866		p += rc;
867	}
868
869	off_dt = fdt32_to_cpu(fdt->off_dt_struct);
870	off_str = fdt32_to_cpu(fdt->off_dt_strings);
871	off_mem_rsvmap = fdt32_to_cpu(fdt->off_mem_rsvmap);
872	version = fdt32_to_cpu(fdt->version);
873	boot_cpuid_phys = fdt32_to_cpu(fdt->boot_cpuid_phys);
874
875	if (off_mem_rsvmap >= totalsize)
876		die("Mem Reserve structure offset exceeds total size\n");
877
878	if (off_dt >= totalsize)
879		die("DT structure offset exceeds total size\n");
880
881	if (off_str > totalsize)
882		die("String table offset exceeds total size\n");
883
884	if (version >= 3) {
885		uint32_t size_str = fdt32_to_cpu(fdt->size_dt_strings);
886		if (off_str+size_str > totalsize)
887			die("String table extends past total size\n");
888		inbuf_init(&strbuf, blob + off_str, blob + off_str + size_str);
889	} else {
890		inbuf_init(&strbuf, blob + off_str, blob + totalsize);
891	}
892
893	if (version >= 17) {
894		size_dt = fdt32_to_cpu(fdt->size_dt_struct);
895		if (off_dt+size_dt > totalsize)
896			die("Structure block extends past total size\n");
897	}
898
899	if (version < 16) {
900		flags |= FTF_FULLPATH | FTF_NAMEPROPS | FTF_VARALIGN;
901	} else {
902		flags |= FTF_NOPS;
903	}
904
905	inbuf_init(&memresvbuf,
906		   blob + off_mem_rsvmap, blob + totalsize);
907	inbuf_init(&dtbuf, blob + off_dt, blob + totalsize);
908
909	reservelist = flat_read_mem_reserve(&memresvbuf);
910
911	val = flat_read_word(&dtbuf);
912
913	if (val != FDT_BEGIN_NODE)
914		die("Device tree blob doesn't begin with FDT_BEGIN_NODE (begins with 0x%08x)\n", val);
915
916	tree = unflatten_tree(&dtbuf, &strbuf, "", flags);
917
918	val = flat_read_word(&dtbuf);
919	if (val != FDT_END)
920		die("Device tree blob doesn't end with FDT_END\n");
921
922	free(blob);
923
924	dtc_close_file(dtcf);
925
926	return build_boot_info(reservelist, tree, boot_cpuid_phys);
927}
928