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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 
32 static 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 
50 struct 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 *, struct label *labels);
56 	void (*endnode)(void *, struct label *labels);
57 	void (*property)(void *, struct label *labels);
58 };
59 
bin_emit_cell(void * e,cell_t val)60 static 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 
bin_emit_string(void * e,char * str,int len)67 static 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 
bin_emit_align(void * e,int a)78 static void bin_emit_align(void *e, int a)
79 {
80 	struct data *dtbuf = e;
81 
82 	*dtbuf = data_append_align(*dtbuf, a);
83 }
84 
bin_emit_data(void * e,struct data d)85 static 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 
bin_emit_beginnode(void * e,struct label * labels)92 static void bin_emit_beginnode(void *e, struct label *labels)
93 {
94 	bin_emit_cell(e, FDT_BEGIN_NODE);
95 }
96 
bin_emit_endnode(void * e,struct label * labels)97 static void bin_emit_endnode(void *e, struct label *labels)
98 {
99 	bin_emit_cell(e, FDT_END_NODE);
100 }
101 
bin_emit_property(void * e,struct label * labels)102 static void bin_emit_property(void *e, struct label *labels)
103 {
104 	bin_emit_cell(e, FDT_PROP);
105 }
106 
107 static 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 
emit_label(FILE * f,const char * prefix,const char * label)117 static 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 
emit_offset_label(FILE * f,const char * label,int offset)124 static 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 
asm_emit_cell(void * e,cell_t val)138 static 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 
asm_emit_string(void * e,char * str,int len)147 static 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 
asm_emit_align(void * e,int a)165 static 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 
asm_emit_data(void * e,struct data d)172 static 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 
asm_emit_beginnode(void * e,struct label * labels)194 static void asm_emit_beginnode(void *e, struct label *labels)
195 {
196 	FILE *f = e;
197 	struct label *l;
198 
199 	for_each_label(labels, l) {
200 		fprintf(f, "\t.globl\t%s\n", l->label);
201 		fprintf(f, "%s:\n", l->label);
202 	}
203 	fprintf(f, "\t/* FDT_BEGIN_NODE */\n");
204 	asm_emit_cell(e, FDT_BEGIN_NODE);
205 }
206 
asm_emit_endnode(void * e,struct label * labels)207 static void asm_emit_endnode(void *e, struct label *labels)
208 {
209 	FILE *f = e;
210 	struct label *l;
211 
212 	fprintf(f, "\t/* FDT_END_NODE */\n");
213 	asm_emit_cell(e, FDT_END_NODE);
214 	for_each_label(labels, l) {
215 		fprintf(f, "\t.globl\t%s_end\n", l->label);
216 		fprintf(f, "%s_end:\n", l->label);
217 	}
218 }
219 
asm_emit_property(void * e,struct label * labels)220 static void asm_emit_property(void *e, struct label *labels)
221 {
222 	FILE *f = e;
223 	struct label *l;
224 
225 	for_each_label(labels, l) {
226 		fprintf(f, "\t.globl\t%s\n", l->label);
227 		fprintf(f, "%s:\n", l->label);
228 	}
229 	fprintf(f, "\t/* FDT_PROP */\n");
230 	asm_emit_cell(e, FDT_PROP);
231 }
232 
233 static struct emitter asm_emitter = {
234 	.cell = asm_emit_cell,
235 	.string = asm_emit_string,
236 	.align = asm_emit_align,
237 	.data = asm_emit_data,
238 	.beginnode = asm_emit_beginnode,
239 	.endnode = asm_emit_endnode,
240 	.property = asm_emit_property,
241 };
242 
stringtable_insert(struct data * d,const char * str)243 static int stringtable_insert(struct data *d, const char *str)
244 {
245 	int i;
246 
247 	/* FIXME: do this more efficiently? */
248 
249 	for (i = 0; i < d->len; i++) {
250 		if (streq(str, d->val + i))
251 			return i;
252 	}
253 
254 	*d = data_append_data(*d, str, strlen(str)+1);
255 	return i;
256 }
257 
flatten_tree(struct node * tree,struct emitter * emit,void * etarget,struct data * strbuf,struct version_info * vi)258 static void flatten_tree(struct node *tree, struct emitter *emit,
259 			 void *etarget, struct data *strbuf,
260 			 struct version_info *vi)
261 {
262 	struct property *prop;
263 	struct node *child;
264 	bool seen_name_prop = false;
265 
266 	if (tree->deleted)
267 		return;
268 
269 	emit->beginnode(etarget, tree->labels);
270 
271 	if (vi->flags & FTF_FULLPATH)
272 		emit->string(etarget, tree->fullpath, 0);
273 	else
274 		emit->string(etarget, tree->name, 0);
275 
276 	emit->align(etarget, sizeof(cell_t));
277 
278 	for_each_property(tree, prop) {
279 		int nameoff;
280 
281 		if (streq(prop->name, "name"))
282 			seen_name_prop = true;
283 
284 		nameoff = stringtable_insert(strbuf, prop->name);
285 
286 		emit->property(etarget, prop->labels);
287 		emit->cell(etarget, prop->val.len);
288 		emit->cell(etarget, nameoff);
289 
290 		if ((vi->flags & FTF_VARALIGN) && (prop->val.len >= 8))
291 			emit->align(etarget, 8);
292 
293 		emit->data(etarget, prop->val);
294 		emit->align(etarget, sizeof(cell_t));
295 	}
296 
297 	if ((vi->flags & FTF_NAMEPROPS) && !seen_name_prop) {
298 		emit->property(etarget, NULL);
299 		emit->cell(etarget, tree->basenamelen+1);
300 		emit->cell(etarget, stringtable_insert(strbuf, "name"));
301 
302 		if ((vi->flags & FTF_VARALIGN) && ((tree->basenamelen+1) >= 8))
303 			emit->align(etarget, 8);
304 
305 		emit->string(etarget, tree->name, tree->basenamelen);
306 		emit->align(etarget, sizeof(cell_t));
307 	}
308 
309 	for_each_child(tree, child) {
310 		flatten_tree(child, emit, etarget, strbuf, vi);
311 	}
312 
313 	emit->endnode(etarget, tree->labels);
314 }
315 
flatten_reserve_list(struct reserve_info * reservelist,struct version_info * vi)316 static struct data flatten_reserve_list(struct reserve_info *reservelist,
317 				 struct version_info *vi)
318 {
319 	struct reserve_info *re;
320 	struct data d = empty_data;
321 	static struct fdt_reserve_entry null_re = {0,0};
322 	int    j;
323 
324 	for (re = reservelist; re; re = re->next) {
325 		d = data_append_re(d, &re->re);
326 	}
327 	/*
328 	 * Add additional reserved slots if the user asked for them.
329 	 */
330 	for (j = 0; j < reservenum; j++) {
331 		d = data_append_re(d, &null_re);
332 	}
333 
334 	return d;
335 }
336 
make_fdt_header(struct fdt_header * fdt,struct version_info * vi,int reservesize,int dtsize,int strsize,int boot_cpuid_phys)337 static void make_fdt_header(struct fdt_header *fdt,
338 			    struct version_info *vi,
339 			    int reservesize, int dtsize, int strsize,
340 			    int boot_cpuid_phys)
341 {
342 	int reserve_off;
343 
344 	reservesize += sizeof(struct fdt_reserve_entry);
345 
346 	memset(fdt, 0xff, sizeof(*fdt));
347 
348 	fdt->magic = cpu_to_fdt32(FDT_MAGIC);
349 	fdt->version = cpu_to_fdt32(vi->version);
350 	fdt->last_comp_version = cpu_to_fdt32(vi->last_comp_version);
351 
352 	/* Reserve map should be doubleword aligned */
353 	reserve_off = ALIGN(vi->hdr_size, 8);
354 
355 	fdt->off_mem_rsvmap = cpu_to_fdt32(reserve_off);
356 	fdt->off_dt_struct = cpu_to_fdt32(reserve_off + reservesize);
357 	fdt->off_dt_strings = cpu_to_fdt32(reserve_off + reservesize
358 					  + dtsize);
359 	fdt->totalsize = cpu_to_fdt32(reserve_off + reservesize + dtsize + strsize);
360 
361 	if (vi->flags & FTF_BOOTCPUID)
362 		fdt->boot_cpuid_phys = cpu_to_fdt32(boot_cpuid_phys);
363 	if (vi->flags & FTF_STRTABSIZE)
364 		fdt->size_dt_strings = cpu_to_fdt32(strsize);
365 	if (vi->flags & FTF_STRUCTSIZE)
366 		fdt->size_dt_struct = cpu_to_fdt32(dtsize);
367 }
368 
dt_to_blob(FILE * f,struct dt_info * dti,int version)369 void dt_to_blob(FILE *f, struct dt_info *dti, int version)
370 {
371 	struct version_info *vi = NULL;
372 	int i;
373 	struct data blob       = empty_data;
374 	struct data reservebuf = empty_data;
375 	struct data dtbuf      = empty_data;
376 	struct data strbuf     = empty_data;
377 	struct fdt_header fdt;
378 	int padlen = 0;
379 
380 	for (i = 0; i < ARRAY_SIZE(version_table); i++) {
381 		if (version_table[i].version == version)
382 			vi = &version_table[i];
383 	}
384 	if (!vi)
385 		die("Unknown device tree blob version %d\n", version);
386 
387 	flatten_tree(dti->dt, &bin_emitter, &dtbuf, &strbuf, vi);
388 	bin_emit_cell(&dtbuf, FDT_END);
389 
390 	reservebuf = flatten_reserve_list(dti->reservelist, vi);
391 
392 	/* Make header */
393 	make_fdt_header(&fdt, vi, reservebuf.len, dtbuf.len, strbuf.len,
394 			dti->boot_cpuid_phys);
395 
396 	/*
397 	 * If the user asked for more space than is used, adjust the totalsize.
398 	 */
399 	if (minsize > 0) {
400 		padlen = minsize - fdt32_to_cpu(fdt.totalsize);
401 		if (padlen < 0) {
402 			padlen = 0;
403 			if (quiet < 1)
404 				fprintf(stderr,
405 					"Warning: blob size %d >= minimum size %d\n",
406 					fdt32_to_cpu(fdt.totalsize), minsize);
407 		}
408 	}
409 
410 	if (padsize > 0)
411 		padlen = padsize;
412 
413 	if (alignsize > 0)
414 		padlen = ALIGN(fdt32_to_cpu(fdt.totalsize) + padlen, alignsize)
415 			- fdt32_to_cpu(fdt.totalsize);
416 
417 	if (padlen > 0) {
418 		int tsize = fdt32_to_cpu(fdt.totalsize);
419 		tsize += padlen;
420 		fdt.totalsize = cpu_to_fdt32(tsize);
421 	}
422 
423 	/*
424 	 * Assemble the blob: start with the header, add with alignment
425 	 * the reserve buffer, add the reserve map terminating zeroes,
426 	 * the device tree itself, and finally the strings.
427 	 */
428 	blob = data_append_data(blob, &fdt, vi->hdr_size);
429 	blob = data_append_align(blob, 8);
430 	blob = data_merge(blob, reservebuf);
431 	blob = data_append_zeroes(blob, sizeof(struct fdt_reserve_entry));
432 	blob = data_merge(blob, dtbuf);
433 	blob = data_merge(blob, strbuf);
434 
435 	/*
436 	 * If the user asked for more space than is used, pad out the blob.
437 	 */
438 	if (padlen > 0)
439 		blob = data_append_zeroes(blob, padlen);
440 
441 	if (fwrite(blob.val, blob.len, 1, f) != 1) {
442 		if (ferror(f))
443 			die("Error writing device tree blob: %s\n",
444 			    strerror(errno));
445 		else
446 			die("Short write on device tree blob\n");
447 	}
448 
449 	/*
450 	 * data_merge() frees the right-hand element so only the blob
451 	 * remains to be freed.
452 	 */
453 	data_free(blob);
454 }
455 
dump_stringtable_asm(FILE * f,struct data strbuf)456 static void dump_stringtable_asm(FILE *f, struct data strbuf)
457 {
458 	const char *p;
459 	int len;
460 
461 	p = strbuf.val;
462 
463 	while (p < (strbuf.val + strbuf.len)) {
464 		len = strlen(p);
465 		fprintf(f, "\t.string \"%s\"\n", p);
466 		p += len+1;
467 	}
468 }
469 
dt_to_asm(FILE * f,struct dt_info * dti,int version)470 void dt_to_asm(FILE *f, struct dt_info *dti, int version)
471 {
472 	struct version_info *vi = NULL;
473 	int i;
474 	struct data strbuf = empty_data;
475 	struct reserve_info *re;
476 	const char *symprefix = "dt";
477 
478 	for (i = 0; i < ARRAY_SIZE(version_table); i++) {
479 		if (version_table[i].version == version)
480 			vi = &version_table[i];
481 	}
482 	if (!vi)
483 		die("Unknown device tree blob version %d\n", version);
484 
485 	fprintf(f, "/* autogenerated by dtc, do not edit */\n\n");
486 
487 	emit_label(f, symprefix, "blob_start");
488 	emit_label(f, symprefix, "header");
489 	fprintf(f, "\t/* magic */\n");
490 	asm_emit_cell(f, FDT_MAGIC);
491 	fprintf(f, "\t/* totalsize */\n");
492 	ASM_EMIT_BELONG(f, "_%s_blob_abs_end - _%s_blob_start",
493 			symprefix, symprefix);
494 	fprintf(f, "\t/* off_dt_struct */\n");
495 	ASM_EMIT_BELONG(f, "_%s_struct_start - _%s_blob_start",
496 		symprefix, symprefix);
497 	fprintf(f, "\t/* off_dt_strings */\n");
498 	ASM_EMIT_BELONG(f, "_%s_strings_start - _%s_blob_start",
499 		symprefix, symprefix);
500 	fprintf(f, "\t/* off_mem_rsvmap */\n");
501 	ASM_EMIT_BELONG(f, "_%s_reserve_map - _%s_blob_start",
502 		symprefix, symprefix);
503 	fprintf(f, "\t/* version */\n");
504 	asm_emit_cell(f, vi->version);
505 	fprintf(f, "\t/* last_comp_version */\n");
506 	asm_emit_cell(f, vi->last_comp_version);
507 
508 	if (vi->flags & FTF_BOOTCPUID) {
509 		fprintf(f, "\t/* boot_cpuid_phys */\n");
510 		asm_emit_cell(f, dti->boot_cpuid_phys);
511 	}
512 
513 	if (vi->flags & FTF_STRTABSIZE) {
514 		fprintf(f, "\t/* size_dt_strings */\n");
515 		ASM_EMIT_BELONG(f, "_%s_strings_end - _%s_strings_start",
516 				symprefix, symprefix);
517 	}
518 
519 	if (vi->flags & FTF_STRUCTSIZE) {
520 		fprintf(f, "\t/* size_dt_struct */\n");
521 		ASM_EMIT_BELONG(f, "_%s_struct_end - _%s_struct_start",
522 			symprefix, symprefix);
523 	}
524 
525 	/*
526 	 * Reserve map entries.
527 	 * Align the reserve map to a doubleword boundary.
528 	 * Each entry is an (address, size) pair of u64 values.
529 	 * Always supply a zero-sized temination entry.
530 	 */
531 	asm_emit_align(f, 8);
532 	emit_label(f, symprefix, "reserve_map");
533 
534 	fprintf(f, "/* Memory reserve map from source file */\n");
535 
536 	/*
537 	 * Use .long on high and low halfs of u64s to avoid .quad
538 	 * as it appears .quad isn't available in some assemblers.
539 	 */
540 	for (re = dti->reservelist; re; re = re->next) {
541 		struct label *l;
542 
543 		for_each_label(re->labels, l) {
544 			fprintf(f, "\t.globl\t%s\n", l->label);
545 			fprintf(f, "%s:\n", l->label);
546 		}
547 		ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->re.address >> 32));
548 		ASM_EMIT_BELONG(f, "0x%08x",
549 				(unsigned int)(re->re.address & 0xffffffff));
550 		ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->re.size >> 32));
551 		ASM_EMIT_BELONG(f, "0x%08x", (unsigned int)(re->re.size & 0xffffffff));
552 	}
553 	for (i = 0; i < reservenum; i++) {
554 		fprintf(f, "\t.long\t0, 0\n\t.long\t0, 0\n");
555 	}
556 
557 	fprintf(f, "\t.long\t0, 0\n\t.long\t0, 0\n");
558 
559 	emit_label(f, symprefix, "struct_start");
560 	flatten_tree(dti->dt, &asm_emitter, f, &strbuf, vi);
561 
562 	fprintf(f, "\t/* FDT_END */\n");
563 	asm_emit_cell(f, FDT_END);
564 	emit_label(f, symprefix, "struct_end");
565 
566 	emit_label(f, symprefix, "strings_start");
567 	dump_stringtable_asm(f, strbuf);
568 	emit_label(f, symprefix, "strings_end");
569 
570 	emit_label(f, symprefix, "blob_end");
571 
572 	/*
573 	 * If the user asked for more space than is used, pad it out.
574 	 */
575 	if (minsize > 0) {
576 		fprintf(f, "\t.space\t%d - (_%s_blob_end - _%s_blob_start), 0\n",
577 			minsize, symprefix, symprefix);
578 	}
579 	if (padsize > 0) {
580 		fprintf(f, "\t.space\t%d, 0\n", padsize);
581 	}
582 	if (alignsize > 0)
583 		asm_emit_align(f, alignsize);
584 	emit_label(f, symprefix, "blob_abs_end");
585 
586 	data_free(strbuf);
587 }
588 
589 struct inbuf {
590 	char *base, *limit, *ptr;
591 };
592 
inbuf_init(struct inbuf * inb,void * base,void * limit)593 static void inbuf_init(struct inbuf *inb, void *base, void *limit)
594 {
595 	inb->base = base;
596 	inb->limit = limit;
597 	inb->ptr = inb->base;
598 }
599 
flat_read_chunk(struct inbuf * inb,void * p,int len)600 static void flat_read_chunk(struct inbuf *inb, void *p, int len)
601 {
602 	if ((inb->ptr + len) > inb->limit)
603 		die("Premature end of data parsing flat device tree\n");
604 
605 	memcpy(p, inb->ptr, len);
606 
607 	inb->ptr += len;
608 }
609 
flat_read_word(struct inbuf * inb)610 static uint32_t flat_read_word(struct inbuf *inb)
611 {
612 	uint32_t val;
613 
614 	assert(((inb->ptr - inb->base) % sizeof(val)) == 0);
615 
616 	flat_read_chunk(inb, &val, sizeof(val));
617 
618 	return fdt32_to_cpu(val);
619 }
620 
flat_realign(struct inbuf * inb,int align)621 static void flat_realign(struct inbuf *inb, int align)
622 {
623 	int off = inb->ptr - inb->base;
624 
625 	inb->ptr = inb->base + ALIGN(off, align);
626 	if (inb->ptr > inb->limit)
627 		die("Premature end of data parsing flat device tree\n");
628 }
629 
flat_read_string(struct inbuf * inb)630 static char *flat_read_string(struct inbuf *inb)
631 {
632 	int len = 0;
633 	const char *p = inb->ptr;
634 	char *str;
635 
636 	do {
637 		if (p >= inb->limit)
638 			die("Premature end of data parsing flat device tree\n");
639 		len++;
640 	} while ((*p++) != '\0');
641 
642 	str = xstrdup(inb->ptr);
643 
644 	inb->ptr += len;
645 
646 	flat_realign(inb, sizeof(uint32_t));
647 
648 	return str;
649 }
650 
flat_read_data(struct inbuf * inb,int len)651 static struct data flat_read_data(struct inbuf *inb, int len)
652 {
653 	struct data d = empty_data;
654 
655 	if (len == 0)
656 		return empty_data;
657 
658 	d = data_grow_for(d, len);
659 	d.len = len;
660 
661 	flat_read_chunk(inb, d.val, len);
662 
663 	flat_realign(inb, sizeof(uint32_t));
664 
665 	return d;
666 }
667 
flat_read_stringtable(struct inbuf * inb,int offset)668 static char *flat_read_stringtable(struct inbuf *inb, int offset)
669 {
670 	const char *p;
671 
672 	p = inb->base + offset;
673 	while (1) {
674 		if (p >= inb->limit || p < inb->base)
675 			die("String offset %d overruns string table\n",
676 			    offset);
677 
678 		if (*p == '\0')
679 			break;
680 
681 		p++;
682 	}
683 
684 	return xstrdup(inb->base + offset);
685 }
686 
flat_read_property(struct inbuf * dtbuf,struct inbuf * strbuf,int flags)687 static struct property *flat_read_property(struct inbuf *dtbuf,
688 					   struct inbuf *strbuf, int flags)
689 {
690 	uint32_t proplen, stroff;
691 	char *name;
692 	struct data val;
693 
694 	proplen = flat_read_word(dtbuf);
695 	stroff = flat_read_word(dtbuf);
696 
697 	name = flat_read_stringtable(strbuf, stroff);
698 
699 	if ((flags & FTF_VARALIGN) && (proplen >= 8))
700 		flat_realign(dtbuf, 8);
701 
702 	val = flat_read_data(dtbuf, proplen);
703 
704 	return build_property(name, val);
705 }
706 
707 
flat_read_mem_reserve(struct inbuf * inb)708 static struct reserve_info *flat_read_mem_reserve(struct inbuf *inb)
709 {
710 	struct reserve_info *reservelist = NULL;
711 	struct reserve_info *new;
712 	struct fdt_reserve_entry re;
713 
714 	/*
715 	 * Each entry is a pair of u64 (addr, size) values for 4 cell_t's.
716 	 * List terminates at an entry with size equal to zero.
717 	 *
718 	 * First pass, count entries.
719 	 */
720 	while (1) {
721 		flat_read_chunk(inb, &re, sizeof(re));
722 		re.address  = fdt64_to_cpu(re.address);
723 		re.size = fdt64_to_cpu(re.size);
724 		if (re.size == 0)
725 			break;
726 
727 		new = build_reserve_entry(re.address, re.size);
728 		reservelist = add_reserve_entry(reservelist, new);
729 	}
730 
731 	return reservelist;
732 }
733 
734 
nodename_from_path(const char * ppath,const char * cpath)735 static char *nodename_from_path(const char *ppath, const char *cpath)
736 {
737 	int plen;
738 
739 	plen = strlen(ppath);
740 
741 	if (!strneq(ppath, cpath, plen))
742 		die("Path \"%s\" is not valid as a child of \"%s\"\n",
743 		    cpath, ppath);
744 
745 	/* root node is a special case */
746 	if (!streq(ppath, "/"))
747 		plen++;
748 
749 	return xstrdup(cpath + plen);
750 }
751 
unflatten_tree(struct inbuf * dtbuf,struct inbuf * strbuf,const char * parent_flatname,int flags)752 static struct node *unflatten_tree(struct inbuf *dtbuf,
753 				   struct inbuf *strbuf,
754 				   const char *parent_flatname, int flags)
755 {
756 	struct node *node;
757 	char *flatname;
758 	uint32_t val;
759 
760 	node = build_node(NULL, NULL);
761 
762 	flatname = flat_read_string(dtbuf);
763 
764 	if (flags & FTF_FULLPATH)
765 		node->name = nodename_from_path(parent_flatname, flatname);
766 	else
767 		node->name = flatname;
768 
769 	do {
770 		struct property *prop;
771 		struct node *child;
772 
773 		val = flat_read_word(dtbuf);
774 		switch (val) {
775 		case FDT_PROP:
776 			if (node->children)
777 				fprintf(stderr, "Warning: Flat tree input has "
778 					"subnodes preceding a property.\n");
779 			prop = flat_read_property(dtbuf, strbuf, flags);
780 			add_property(node, prop);
781 			break;
782 
783 		case FDT_BEGIN_NODE:
784 			child = unflatten_tree(dtbuf,strbuf, flatname, flags);
785 			add_child(node, child);
786 			break;
787 
788 		case FDT_END_NODE:
789 			break;
790 
791 		case FDT_END:
792 			die("Premature FDT_END in device tree blob\n");
793 			break;
794 
795 		case FDT_NOP:
796 			if (!(flags & FTF_NOPS))
797 				fprintf(stderr, "Warning: NOP tag found in flat tree"
798 					" version <16\n");
799 
800 			/* Ignore */
801 			break;
802 
803 		default:
804 			die("Invalid opcode word %08x in device tree blob\n",
805 			    val);
806 		}
807 	} while (val != FDT_END_NODE);
808 
809 	if (node->name != flatname) {
810 		free(flatname);
811 	}
812 
813 	return node;
814 }
815 
816 
dt_from_blob(const char * fname)817 struct dt_info *dt_from_blob(const char *fname)
818 {
819 	FILE *f;
820 	uint32_t magic, totalsize, version, size_dt, boot_cpuid_phys;
821 	uint32_t off_dt, off_str, off_mem_rsvmap;
822 	int rc;
823 	char *blob;
824 	struct fdt_header *fdt;
825 	char *p;
826 	struct inbuf dtbuf, strbuf;
827 	struct inbuf memresvbuf;
828 	int sizeleft;
829 	struct reserve_info *reservelist;
830 	struct node *tree;
831 	uint32_t val;
832 	int flags = 0;
833 
834 	f = srcfile_relative_open(fname, NULL);
835 
836 	rc = fread(&magic, sizeof(magic), 1, f);
837 	if (ferror(f))
838 		die("Error reading DT blob magic number: %s\n",
839 		    strerror(errno));
840 	if (rc < 1) {
841 		if (feof(f))
842 			die("EOF reading DT blob magic number\n");
843 		else
844 			die("Mysterious short read reading magic number\n");
845 	}
846 
847 	magic = fdt32_to_cpu(magic);
848 	if (magic != FDT_MAGIC)
849 		die("Blob has incorrect magic number\n");
850 
851 	rc = fread(&totalsize, sizeof(totalsize), 1, f);
852 	if (ferror(f))
853 		die("Error reading DT blob size: %s\n", strerror(errno));
854 	if (rc < 1) {
855 		if (feof(f))
856 			die("EOF reading DT blob size\n");
857 		else
858 			die("Mysterious short read reading blob size\n");
859 	}
860 
861 	totalsize = fdt32_to_cpu(totalsize);
862 	if (totalsize < FDT_V1_SIZE)
863 		die("DT blob size (%d) is too small\n", totalsize);
864 
865 	blob = xmalloc(totalsize);
866 
867 	fdt = (struct fdt_header *)blob;
868 	fdt->magic = cpu_to_fdt32(magic);
869 	fdt->totalsize = cpu_to_fdt32(totalsize);
870 
871 	sizeleft = totalsize - sizeof(magic) - sizeof(totalsize);
872 	p = blob + sizeof(magic)  + sizeof(totalsize);
873 
874 	while (sizeleft) {
875 		if (feof(f))
876 			die("EOF before reading %d bytes of DT blob\n",
877 			    totalsize);
878 
879 		rc = fread(p, 1, sizeleft, f);
880 		if (ferror(f))
881 			die("Error reading DT blob: %s\n",
882 			    strerror(errno));
883 
884 		sizeleft -= rc;
885 		p += rc;
886 	}
887 
888 	off_dt = fdt32_to_cpu(fdt->off_dt_struct);
889 	off_str = fdt32_to_cpu(fdt->off_dt_strings);
890 	off_mem_rsvmap = fdt32_to_cpu(fdt->off_mem_rsvmap);
891 	version = fdt32_to_cpu(fdt->version);
892 	boot_cpuid_phys = fdt32_to_cpu(fdt->boot_cpuid_phys);
893 
894 	if (off_mem_rsvmap >= totalsize)
895 		die("Mem Reserve structure offset exceeds total size\n");
896 
897 	if (off_dt >= totalsize)
898 		die("DT structure offset exceeds total size\n");
899 
900 	if (off_str > totalsize)
901 		die("String table offset exceeds total size\n");
902 
903 	if (version >= 3) {
904 		uint32_t size_str = fdt32_to_cpu(fdt->size_dt_strings);
905 		if ((off_str+size_str < off_str) || (off_str+size_str > totalsize))
906 			die("String table extends past total size\n");
907 		inbuf_init(&strbuf, blob + off_str, blob + off_str + size_str);
908 	} else {
909 		inbuf_init(&strbuf, blob + off_str, blob + totalsize);
910 	}
911 
912 	if (version >= 17) {
913 		size_dt = fdt32_to_cpu(fdt->size_dt_struct);
914 		if ((off_dt+size_dt < off_dt) || (off_dt+size_dt > totalsize))
915 			die("Structure block extends past total size\n");
916 	}
917 
918 	if (version < 16) {
919 		flags |= FTF_FULLPATH | FTF_NAMEPROPS | FTF_VARALIGN;
920 	} else {
921 		flags |= FTF_NOPS;
922 	}
923 
924 	inbuf_init(&memresvbuf,
925 		   blob + off_mem_rsvmap, blob + totalsize);
926 	inbuf_init(&dtbuf, blob + off_dt, blob + totalsize);
927 
928 	reservelist = flat_read_mem_reserve(&memresvbuf);
929 
930 	val = flat_read_word(&dtbuf);
931 
932 	if (val != FDT_BEGIN_NODE)
933 		die("Device tree blob doesn't begin with FDT_BEGIN_NODE (begins with 0x%08x)\n", val);
934 
935 	tree = unflatten_tree(&dtbuf, &strbuf, "", flags);
936 
937 	val = flat_read_word(&dtbuf);
938 	if (val != FDT_END)
939 		die("Device tree blob doesn't end with FDT_END\n");
940 
941 	free(blob);
942 
943 	fclose(f);
944 
945 	return build_dt_info(DTSF_V1, reservelist, tree, boot_cpuid_phys);
946 }
947