xref: /openbmc/u-boot/tools/fdtgrep.c (revision 5c8fd32b)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2013, Google Inc.
4  * Written by Simon Glass <sjg@chromium.org>
5  *
6  * Perform a grep of an FDT either displaying the source subset or producing
7  * a new .dtb subset which can be used as required.
8  */
9 
10 #include <assert.h>
11 #include <ctype.h>
12 #include <errno.h>
13 #include <getopt.h>
14 #include <fcntl.h>
15 #include <stdbool.h>
16 #include <stdio.h>
17 #include <stdlib.h>
18 #include <string.h>
19 #include <unistd.h>
20 
21 #include "fdt_host.h"
22 #include "libfdt_internal.h"
23 
24 /* Define DEBUG to get some debugging output on stderr */
25 #ifdef DEBUG
26 #define debug(a, b...) fprintf(stderr, a, ## b)
27 #else
28 #define debug(a, b...)
29 #endif
30 
31 /* A linked list of values we are grepping for */
32 struct value_node {
33 	int type;		/* Types this value matches (FDT_IS... mask) */
34 	int include;		/* 1 to include matches, 0 to exclude */
35 	const char *string;	/* String to match */
36 	struct value_node *next;	/* Pointer to next node, or NULL */
37 };
38 
39 /* Output formats we support */
40 enum output_t {
41 	OUT_DTS,		/* Device tree source */
42 	OUT_DTB,		/* Valid device tree binary */
43 	OUT_BIN,		/* Fragment of .dtb, for hashing */
44 };
45 
46 /* Holds information which controls our output and options */
47 struct display_info {
48 	enum output_t output;	/* Output format */
49 	int add_aliases;	/* Add aliases node to output */
50 	int all;		/* Display all properties/nodes */
51 	int colour;		/* Display output in ANSI colour */
52 	int region_list;	/* Output a region list */
53 	int flags;		/* Flags (FDT_REG_...) */
54 	int list_strings;	/* List strings in string table */
55 	int show_offset;	/* Show offset */
56 	int show_addr;		/* Show address */
57 	int header;		/* Output an FDT header */
58 	int diff;		/* Show +/- diff markers */
59 	int include_root;	/* Include the root node and all properties */
60 	int remove_strings;	/* Remove unused strings */
61 	int show_dts_version;	/* Put '/dts-v1/;' on the first line */
62 	int types_inc;		/* Mask of types that we include (FDT_IS...) */
63 	int types_exc;		/* Mask of types that we exclude (FDT_IS...) */
64 	int invert;		/* Invert polarity of match */
65 	struct value_node *value_head;	/* List of values to match */
66 	const char *output_fname;	/* Output filename */
67 	FILE *fout;		/* File to write dts/dtb output */
68 };
69 
70 static void report_error(const char *where, int err)
71 {
72 	fprintf(stderr, "Error at '%s': %s\n", where, fdt_strerror(err));
73 }
74 
75 /* Supported ANSI colours */
76 enum {
77 	COL_BLACK,
78 	COL_RED,
79 	COL_GREEN,
80 	COL_YELLOW,
81 	COL_BLUE,
82 	COL_MAGENTA,
83 	COL_CYAN,
84 	COL_WHITE,
85 
86 	COL_NONE = -1,
87 };
88 
89 /**
90  * print_ansi_colour() - Print out the ANSI sequence for a colour
91  *
92  * @fout:	Output file
93  * @col:	Colour to output (COL_...), or COL_NONE to reset colour
94  */
95 static void print_ansi_colour(FILE *fout, int col)
96 {
97 	if (col == COL_NONE)
98 		fprintf(fout, "\033[0m");
99 	else
100 		fprintf(fout, "\033[1;%dm", col + 30);
101 }
102 
103 
104 /**
105  * value_add() - Add a new value to our list of things to grep for
106  *
107  * @disp:	Display structure, holding info about our options
108  * @headp:	Pointer to header pointer of list
109  * @type:	Type of this value (FDT_IS_...)
110  * @include:	1 if we want to include matches, 0 to exclude
111  * @str:	String value to match
112  */
113 static int value_add(struct display_info *disp, struct value_node **headp,
114 		     int type, int include, const char *str)
115 {
116 	struct value_node *node;
117 
118 	/*
119 	 * Keep track of which types we are excluding/including. We don't
120 	 * allow both including and excluding things, because it doesn't make
121 	 * sense. 'Including' means that everything not mentioned is
122 	 * excluded. 'Excluding' means that everything not mentioned is
123 	 * included. So using the two together would be meaningless.
124 	 */
125 	if (include)
126 		disp->types_inc |= type;
127 	else
128 		disp->types_exc |= type;
129 	if (disp->types_inc & disp->types_exc & type) {
130 		fprintf(stderr,
131 			"Cannot use both include and exclude for '%s'\n", str);
132 		return -1;
133 	}
134 
135 	str = strdup(str);
136 	if (!str)
137 		goto err_mem;
138 	node = malloc(sizeof(*node));
139 	if (!node)
140 		goto err_mem;
141 	node->next = *headp;
142 	node->type = type;
143 	node->include = include;
144 	node->string = str;
145 	*headp = node;
146 
147 	return 0;
148 err_mem:
149 	fprintf(stderr, "Out of memory\n");
150 	return -1;
151 }
152 
153 static bool util_is_printable_string(const void *data, int len)
154 {
155 	const char *s = data;
156 	const char *ss, *se;
157 
158 	/* zero length is not */
159 	if (len == 0)
160 		return 0;
161 
162 	/* must terminate with zero */
163 	if (s[len - 1] != '\0')
164 		return 0;
165 
166 	se = s + len;
167 
168 	while (s < se) {
169 		ss = s;
170 		while (s < se && *s && isprint((unsigned char)*s))
171 			s++;
172 
173 		/* not zero, or not done yet */
174 		if (*s != '\0' || s == ss)
175 			return 0;
176 
177 		s++;
178 	}
179 
180 	return 1;
181 }
182 
183 static void utilfdt_print_data(const char *data, int len)
184 {
185 	int i;
186 	const char *p = data;
187 	const char *s;
188 
189 	/* no data, don't print */
190 	if (len == 0)
191 		return;
192 
193 	if (util_is_printable_string(data, len)) {
194 		printf(" = ");
195 
196 		s = data;
197 		do {
198 			printf("\"%s\"", s);
199 			s += strlen(s) + 1;
200 			if (s < data + len)
201 				printf(", ");
202 		} while (s < data + len);
203 
204 	} else if ((len % 4) == 0) {
205 		const uint32_t *cell = (const uint32_t *)data;
206 
207 		printf(" = <");
208 		for (i = 0, len /= 4; i < len; i++)
209 			printf("0x%08x%s", fdt32_to_cpu(cell[i]),
210 			       i < (len - 1) ? " " : "");
211 		printf(">");
212 	} else {
213 		printf(" = [");
214 		for (i = 0; i < len; i++)
215 			printf("%02x%s", *p++, i < len - 1 ? " " : "");
216 		printf("]");
217 	}
218 }
219 
220 /**
221  * display_fdt_by_regions() - Display regions of an FDT source
222  *
223  * This dumps an FDT as source, but only certain regions of it. This is the
224  * final stage of the grep - we have a list of regions we want to display,
225  * and this function displays them.
226  *
227  * @disp:	Display structure, holding info about our options
228  * @blob:	FDT blob to display
229  * @region:	List of regions to display
230  * @count:	Number of regions
231  */
232 static int display_fdt_by_regions(struct display_info *disp, const void *blob,
233 		struct fdt_region region[], int count)
234 {
235 	struct fdt_region *reg = region, *reg_end = region + count;
236 	uint32_t off_mem_rsvmap = fdt_off_mem_rsvmap(blob);
237 	int base = fdt_off_dt_struct(blob);
238 	int version = fdt_version(blob);
239 	int offset, nextoffset;
240 	int tag, depth, shift;
241 	FILE *f = disp->fout;
242 	uint64_t addr, size;
243 	int in_region;
244 	int file_ofs;
245 	int i;
246 
247 	if (disp->show_dts_version)
248 		fprintf(f, "/dts-v1/;\n");
249 
250 	if (disp->header) {
251 		fprintf(f, "// magic:\t\t0x%x\n", fdt_magic(blob));
252 		fprintf(f, "// totalsize:\t\t0x%x (%d)\n", fdt_totalsize(blob),
253 			fdt_totalsize(blob));
254 		fprintf(f, "// off_dt_struct:\t0x%x\n",
255 			fdt_off_dt_struct(blob));
256 		fprintf(f, "// off_dt_strings:\t0x%x\n",
257 			fdt_off_dt_strings(blob));
258 		fprintf(f, "// off_mem_rsvmap:\t0x%x\n", off_mem_rsvmap);
259 		fprintf(f, "// version:\t\t%d\n", version);
260 		fprintf(f, "// last_comp_version:\t%d\n",
261 			fdt_last_comp_version(blob));
262 		if (version >= 2) {
263 			fprintf(f, "// boot_cpuid_phys:\t0x%x\n",
264 				fdt_boot_cpuid_phys(blob));
265 		}
266 		if (version >= 3) {
267 			fprintf(f, "// size_dt_strings:\t0x%x\n",
268 				fdt_size_dt_strings(blob));
269 		}
270 		if (version >= 17) {
271 			fprintf(f, "// size_dt_struct:\t0x%x\n",
272 				fdt_size_dt_struct(blob));
273 		}
274 		fprintf(f, "\n");
275 	}
276 
277 	if (disp->flags & FDT_REG_ADD_MEM_RSVMAP) {
278 		const struct fdt_reserve_entry *p_rsvmap;
279 
280 		p_rsvmap = (const struct fdt_reserve_entry *)
281 				((const char *)blob + off_mem_rsvmap);
282 		for (i = 0; ; i++) {
283 			addr = fdt64_to_cpu(p_rsvmap[i].address);
284 			size = fdt64_to_cpu(p_rsvmap[i].size);
285 			if (addr == 0 && size == 0)
286 				break;
287 
288 			fprintf(f, "/memreserve/ %llx %llx;\n",
289 				(unsigned long long)addr,
290 				(unsigned long long)size);
291 		}
292 	}
293 
294 	depth = 0;
295 	nextoffset = 0;
296 	shift = 4;	/* 4 spaces per indent */
297 	do {
298 		const struct fdt_property *prop;
299 		const char *name;
300 		int show;
301 		int len;
302 
303 		offset = nextoffset;
304 
305 		/*
306 		 * Work out the file offset of this offset, and decide
307 		 * whether it is in the region list or not
308 		 */
309 		file_ofs = base + offset;
310 		if (reg < reg_end && file_ofs >= reg->offset + reg->size)
311 			reg++;
312 		in_region = reg < reg_end && file_ofs >= reg->offset &&
313 				file_ofs < reg->offset + reg->size;
314 		tag = fdt_next_tag(blob, offset, &nextoffset);
315 
316 		if (tag == FDT_END)
317 			break;
318 		show = in_region || disp->all;
319 		if (show && disp->diff)
320 			fprintf(f, "%c", in_region ? '+' : '-');
321 
322 		if (!show) {
323 			/* Do this here to avoid 'if (show)' in every 'case' */
324 			if (tag == FDT_BEGIN_NODE)
325 				depth++;
326 			else if (tag == FDT_END_NODE)
327 				depth--;
328 			continue;
329 		}
330 		if (tag != FDT_END) {
331 			if (disp->show_addr)
332 				fprintf(f, "%4x: ", file_ofs);
333 			if (disp->show_offset)
334 				fprintf(f, "%4x: ", file_ofs - base);
335 		}
336 
337 		/* Green means included, red means excluded */
338 		if (disp->colour)
339 			print_ansi_colour(f, in_region ? COL_GREEN : COL_RED);
340 
341 		switch (tag) {
342 		case FDT_PROP:
343 			prop = fdt_get_property_by_offset(blob, offset, NULL);
344 			name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
345 			fprintf(f, "%*s%s", depth * shift, "", name);
346 			utilfdt_print_data(prop->data,
347 					   fdt32_to_cpu(prop->len));
348 			fprintf(f, ";");
349 			break;
350 
351 		case FDT_NOP:
352 			fprintf(f, "%*s// [NOP]", depth * shift, "");
353 			break;
354 
355 		case FDT_BEGIN_NODE:
356 			name = fdt_get_name(blob, offset, &len);
357 			fprintf(f, "%*s%s {", depth++ * shift, "",
358 				*name ? name : "/");
359 			break;
360 
361 		case FDT_END_NODE:
362 			fprintf(f, "%*s};", --depth * shift, "");
363 			break;
364 		}
365 
366 		/* Reset colour back to normal before end of line */
367 		if (disp->colour)
368 			print_ansi_colour(f, COL_NONE);
369 		fprintf(f, "\n");
370 	} while (1);
371 
372 	/* Print a list of strings if requested */
373 	if (disp->list_strings) {
374 		const char *str;
375 		int str_base = fdt_off_dt_strings(blob);
376 
377 		for (offset = 0; offset < fdt_size_dt_strings(blob);
378 				offset += strlen(str) + 1) {
379 			str = fdt_string(blob, offset);
380 			int len = strlen(str) + 1;
381 			int show;
382 
383 			/* Only print strings that are in the region */
384 			file_ofs = str_base + offset;
385 			in_region = reg < reg_end &&
386 					file_ofs >= reg->offset &&
387 					file_ofs + len < reg->offset +
388 						reg->size;
389 			show = in_region || disp->all;
390 			if (show && disp->diff)
391 				printf("%c", in_region ? '+' : '-');
392 			if (disp->show_addr)
393 				printf("%4x: ", file_ofs);
394 			if (disp->show_offset)
395 				printf("%4x: ", offset);
396 			printf("%s\n", str);
397 		}
398 	}
399 
400 	return 0;
401 }
402 
403 /**
404  * dump_fdt_regions() - Dump regions of an FDT as binary data
405  *
406  * This dumps an FDT as binary, but only certain regions of it. This is the
407  * final stage of the grep - we have a list of regions we want to dump,
408  * and this function dumps them.
409  *
410  * The output of this function may or may not be a valid FDT. To ensure it
411  * is, these disp->flags must be set:
412  *
413  *   FDT_REG_SUPERNODES: ensures that subnodes are preceded by their
414  *		parents. Without this option, fragments of subnode data may be
415  *		output without the supernodes above them. This is useful for
416  *		hashing but cannot produce a valid FDT.
417  *   FDT_REG_ADD_STRING_TAB: Adds a string table to the end of the FDT.
418  *		Without this none of the properties will have names
419  *   FDT_REG_ADD_MEM_RSVMAP: Adds a mem_rsvmap table - an FDT is invalid
420  *		without this.
421  *
422  * @disp:	Display structure, holding info about our options
423  * @blob:	FDT blob to display
424  * @region:	List of regions to display
425  * @count:	Number of regions
426  * @out:	Output destination
427  */
428 static int dump_fdt_regions(struct display_info *disp, const void *blob,
429 		struct fdt_region region[], int count, char *out)
430 {
431 	struct fdt_header *fdt;
432 	int size, struct_start;
433 	int ptr;
434 	int i;
435 
436 	/* Set up a basic header (even if we don't actually write it) */
437 	fdt = (struct fdt_header *)out;
438 	memset(fdt, '\0', sizeof(*fdt));
439 	fdt_set_magic(fdt, FDT_MAGIC);
440 	struct_start = FDT_ALIGN(sizeof(struct fdt_header),
441 					sizeof(struct fdt_reserve_entry));
442 	fdt_set_off_mem_rsvmap(fdt, struct_start);
443 	fdt_set_version(fdt, FDT_LAST_SUPPORTED_VERSION);
444 	fdt_set_last_comp_version(fdt, FDT_FIRST_SUPPORTED_VERSION);
445 
446 	/*
447 	 * Calculate the total size of the regions we are writing out. The
448 	 * first will be the mem_rsvmap if the FDT_REG_ADD_MEM_RSVMAP flag
449 	 * is set. The last will be the string table if FDT_REG_ADD_STRING_TAB
450 	 * is set.
451 	 */
452 	for (i = size = 0; i < count; i++)
453 		size += region[i].size;
454 
455 	/* Bring in the mem_rsvmap section from the old file if requested */
456 	if (count > 0 && (disp->flags & FDT_REG_ADD_MEM_RSVMAP)) {
457 		struct_start += region[0].size;
458 		size -= region[0].size;
459 	}
460 	fdt_set_off_dt_struct(fdt, struct_start);
461 
462 	/* Update the header to have the correct offsets/sizes */
463 	if (count >= 2 && (disp->flags & FDT_REG_ADD_STRING_TAB)) {
464 		int str_size;
465 
466 		str_size = region[count - 1].size;
467 		fdt_set_size_dt_struct(fdt, size - str_size);
468 		fdt_set_off_dt_strings(fdt, struct_start + size - str_size);
469 		fdt_set_size_dt_strings(fdt, str_size);
470 		fdt_set_totalsize(fdt, struct_start + size);
471 	}
472 
473 	/* Write the header if required */
474 	ptr = 0;
475 	if (disp->header) {
476 		ptr = sizeof(*fdt);
477 		while (ptr < fdt_off_mem_rsvmap(fdt))
478 			out[ptr++] = '\0';
479 	}
480 
481 	/* Output all the nodes including any mem_rsvmap/string table */
482 	for (i = 0; i < count; i++) {
483 		struct fdt_region *reg = &region[i];
484 
485 		memcpy(out + ptr, (const char *)blob + reg->offset, reg->size);
486 		ptr += reg->size;
487 	}
488 
489 	return ptr;
490 }
491 
492 /**
493  * show_region_list() - Print out a list of regions
494  *
495  * The list includes the region offset (absolute offset from start of FDT
496  * blob in bytes) and size
497  *
498  * @reg:	List of regions to print
499  * @count:	Number of regions
500  */
501 static void show_region_list(struct fdt_region *reg, int count)
502 {
503 	int i;
504 
505 	printf("Regions: %d\n", count);
506 	for (i = 0; i < count; i++, reg++) {
507 		printf("%d:  %-10x  %-10x\n", i, reg->offset,
508 		       reg->offset + reg->size);
509 	}
510 }
511 
512 static int check_type_include(void *priv, int type, const char *data, int size)
513 {
514 	struct display_info *disp = priv;
515 	struct value_node *val;
516 	int match, none_match = FDT_IS_ANY;
517 
518 	/* If none of our conditions mention this type, we know nothing */
519 	debug("type=%x, data=%s\n", type, data ? data : "(null)");
520 	if (!((disp->types_inc | disp->types_exc) & type)) {
521 		debug("   - not in any condition\n");
522 		return -1;
523 	}
524 
525 	/*
526 	 * Go through the list of conditions. For inclusive conditions, we
527 	 * return 1 at the first match. For exclusive conditions, we must
528 	 * check that there are no matches.
529 	 */
530 	if (data) {
531 		for (val = disp->value_head; val; val = val->next) {
532 			if (!(type & val->type))
533 				continue;
534 			match = fdt_stringlist_contains(data, size,
535 							val->string);
536 			debug("      - val->type=%x, str='%s', match=%d\n",
537 			      val->type, val->string, match);
538 			if (match && val->include) {
539 				debug("   - match inc %s\n", val->string);
540 				return 1;
541 			}
542 			if (match)
543 				none_match &= ~val->type;
544 		}
545 	}
546 
547 	/*
548 	 * If this is an exclusive condition, and nothing matches, then we
549 	 * should return 1.
550 	 */
551 	if ((type & disp->types_exc) && (none_match & type)) {
552 		debug("   - match exc\n");
553 		/*
554 		 * Allow FDT_IS_COMPAT to make the final decision in the
555 		 * case where there is no specific type
556 		 */
557 		if (type == FDT_IS_NODE && disp->types_exc == FDT_ANY_GLOBAL) {
558 			debug("   - supressed exc node\n");
559 			return -1;
560 		}
561 		return 1;
562 	}
563 
564 	/*
565 	 * Allow FDT_IS_COMPAT to make the final decision in the
566 	 * case where there is no specific type (inclusive)
567 	 */
568 	if (type == FDT_IS_NODE && disp->types_inc == FDT_ANY_GLOBAL)
569 		return -1;
570 
571 	debug("   - no match, types_inc=%x, types_exc=%x, none_match=%x\n",
572 	      disp->types_inc, disp->types_exc, none_match);
573 
574 	return 0;
575 }
576 
577 /**
578  * h_include() - Include handler function for fdt_find_regions()
579  *
580  * This function decides whether to include or exclude a node, property or
581  * compatible string. The function is defined by fdt_find_regions().
582  *
583  * The algorithm is documented in the code - disp->invert is 0 for normal
584  * operation, and 1 to invert the sense of all matches.
585  *
586  * See
587  */
588 static int h_include(void *priv, const void *fdt, int offset, int type,
589 		     const char *data, int size)
590 {
591 	struct display_info *disp = priv;
592 	int inc, len;
593 
594 	inc = check_type_include(priv, type, data, size);
595 	if (disp->include_root && type == FDT_IS_PROP && offset == 0 && inc)
596 		return 1;
597 
598 	/*
599 	 * If the node name does not tell us anything, check the
600 	 * compatible string
601 	 */
602 	if (inc == -1 && type == FDT_IS_NODE) {
603 		debug("   - checking compatible2\n");
604 		data = fdt_getprop(fdt, offset, "compatible", &len);
605 		inc = check_type_include(priv, FDT_IS_COMPAT, data, len);
606 	}
607 
608 	/* If we still have no idea, check for properties in the node */
609 	if (inc != 1 && type == FDT_IS_NODE &&
610 	    (disp->types_inc & FDT_NODE_HAS_PROP)) {
611 		debug("   - checking node '%s'\n",
612 		      fdt_get_name(fdt, offset, NULL));
613 		for (offset = fdt_first_property_offset(fdt, offset);
614 		     offset > 0 && inc != 1;
615 		     offset = fdt_next_property_offset(fdt, offset)) {
616 			const struct fdt_property *prop;
617 			const char *str;
618 
619 			prop = fdt_get_property_by_offset(fdt, offset, NULL);
620 			if (!prop)
621 				continue;
622 			str = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
623 			inc = check_type_include(priv, FDT_NODE_HAS_PROP, str,
624 						 strlen(str));
625 		}
626 		if (inc == -1)
627 			inc = 0;
628 	}
629 
630 	switch (inc) {
631 	case 1:
632 		inc = !disp->invert;
633 		break;
634 	case 0:
635 		inc = disp->invert;
636 		break;
637 	}
638 	debug("   - returning %d\n", inc);
639 
640 	return inc;
641 }
642 
643 static int h_cmp_region(const void *v1, const void *v2)
644 {
645 	const struct fdt_region *region1 = v1, *region2 = v2;
646 
647 	return region1->offset - region2->offset;
648 }
649 
650 static int fdtgrep_find_regions(const void *fdt,
651 		int (*include_func)(void *priv, const void *fdt, int offset,
652 				 int type, const char *data, int size),
653 		struct display_info *disp, struct fdt_region *region,
654 		int max_regions, char *path, int path_len, int flags)
655 {
656 	struct fdt_region_state state;
657 	int count;
658 	int ret;
659 
660 	count = 0;
661 	ret = fdt_first_region(fdt, include_func, disp,
662 			&region[count++], path, path_len,
663 			disp->flags, &state);
664 	while (ret == 0) {
665 		ret = fdt_next_region(fdt, include_func, disp,
666 				count < max_regions ? &region[count] : NULL,
667 				path, path_len, disp->flags, &state);
668 		if (!ret)
669 			count++;
670 	}
671 	if (ret && ret != -FDT_ERR_NOTFOUND)
672 		return ret;
673 
674 	/* Find all the aliases and add those regions back in */
675 	if (disp->add_aliases && count < max_regions) {
676 		int new_count;
677 
678 		new_count = fdt_add_alias_regions(fdt, region, count,
679 						  max_regions, &state);
680 		if (new_count == -FDT_ERR_NOTFOUND) {
681 			/* No alias node found */
682 		} else if (new_count < 0) {
683 			return new_count;
684 		} else if (new_count <= max_regions) {
685 			/*
686 			* The alias regions will now be at the end of the list.
687 			* Sort the regions by offset to get things into the
688 			* right order
689 			*/
690 			count = new_count;
691 			qsort(region, count, sizeof(struct fdt_region),
692 			      h_cmp_region);
693 		}
694 	}
695 
696 	return count;
697 }
698 
699 int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len)
700 {
701 	int fd = 0;	/* assume stdin */
702 	char *buf = NULL;
703 	off_t bufsize = 1024, offset = 0;
704 	int ret = 0;
705 
706 	*buffp = NULL;
707 	if (strcmp(filename, "-") != 0) {
708 		fd = open(filename, O_RDONLY);
709 		if (fd < 0)
710 			return errno;
711 	}
712 
713 	/* Loop until we have read everything */
714 	buf = malloc(bufsize);
715 	if (!buf)
716 		return -ENOMEM;
717 	do {
718 		/* Expand the buffer to hold the next chunk */
719 		if (offset == bufsize) {
720 			bufsize *= 2;
721 			buf = realloc(buf, bufsize);
722 			if (!buf)
723 				return -ENOMEM;
724 		}
725 
726 		ret = read(fd, &buf[offset], bufsize - offset);
727 		if (ret < 0) {
728 			ret = errno;
729 			break;
730 		}
731 		offset += ret;
732 	} while (ret != 0);
733 
734 	/* Clean up, including closing stdin; return errno on error */
735 	close(fd);
736 	if (ret)
737 		free(buf);
738 	else
739 		*buffp = buf;
740 	*len = bufsize;
741 	return ret;
742 }
743 
744 int utilfdt_read_err(const char *filename, char **buffp)
745 {
746 	off_t len;
747 	return utilfdt_read_err_len(filename, buffp, &len);
748 }
749 
750 char *utilfdt_read_len(const char *filename, off_t *len)
751 {
752 	char *buff;
753 	int ret = utilfdt_read_err_len(filename, &buff, len);
754 
755 	if (ret) {
756 		fprintf(stderr, "Couldn't open blob from '%s': %s\n", filename,
757 			strerror(ret));
758 		return NULL;
759 	}
760 	/* Successful read */
761 	return buff;
762 }
763 
764 char *utilfdt_read(const char *filename)
765 {
766 	off_t len;
767 	return utilfdt_read_len(filename, &len);
768 }
769 
770 /**
771  * Run the main fdtgrep operation, given a filename and valid arguments
772  *
773  * @param disp		Display information / options
774  * @param filename	Filename of blob file
775  * @param return 0 if ok, -ve on error
776  */
777 static int do_fdtgrep(struct display_info *disp, const char *filename)
778 {
779 	struct fdt_region *region = NULL;
780 	int max_regions;
781 	int count = 100;
782 	char path[1024];
783 	char *blob;
784 	int i, ret;
785 
786 	blob = utilfdt_read(filename);
787 	if (!blob)
788 		return -1;
789 	ret = fdt_check_header(blob);
790 	if (ret) {
791 		fprintf(stderr, "Error: %s\n", fdt_strerror(ret));
792 		return ret;
793 	}
794 
795 	/* Allow old files, but they are untested */
796 	if (fdt_version(blob) < 17 && disp->value_head) {
797 		fprintf(stderr,
798 			"Warning: fdtgrep does not fully support version %d files\n",
799 			fdt_version(blob));
800 	}
801 
802 	/*
803 	 * We do two passes, since we don't know how many regions we need.
804 	 * The first pass will count the regions, but if it is too many,
805 	 * we do another pass to actually record them.
806 	 */
807 	for (i = 0; i < 2; i++) {
808 		region = malloc(count * sizeof(struct fdt_region));
809 		if (!region) {
810 			fprintf(stderr, "Out of memory for %d regions\n",
811 				count);
812 			return -1;
813 		}
814 		max_regions = count;
815 		count = fdtgrep_find_regions(blob,
816 				h_include, disp,
817 				region, max_regions, path, sizeof(path),
818 				disp->flags);
819 		if (count < 0) {
820 			report_error("fdt_find_regions", count);
821 			free(region);
822 			return -1;
823 		}
824 		if (count <= max_regions)
825 			break;
826 		free(region);
827 		fprintf(stderr, "Internal error with fdtgrep_find_region)(\n");
828 		return -1;
829 	}
830 
831 	/* Optionally print a list of regions */
832 	if (disp->region_list)
833 		show_region_list(region, count);
834 
835 	/* Output either source .dts or binary .dtb */
836 	if (disp->output == OUT_DTS) {
837 		ret = display_fdt_by_regions(disp, blob, region, count);
838 	} else {
839 		void *fdt;
840 		/* Allow reserved memory section to expand slightly */
841 		int size = fdt_totalsize(blob) + 16;
842 
843 		fdt = malloc(size);
844 		if (!fdt) {
845 			fprintf(stderr, "Out_of_memory\n");
846 			ret = -1;
847 			goto err;
848 		}
849 		size = dump_fdt_regions(disp, blob, region, count, fdt);
850 		if (disp->remove_strings) {
851 			void *out;
852 
853 			out = malloc(size);
854 			if (!out) {
855 				fprintf(stderr, "Out_of_memory\n");
856 				ret = -1;
857 				goto err;
858 			}
859 			ret = fdt_remove_unused_strings(fdt, out);
860 			if (ret < 0) {
861 				fprintf(stderr,
862 					"Failed to remove unused strings: err=%d\n",
863 					ret);
864 				goto err;
865 			}
866 			free(fdt);
867 			fdt = out;
868 			ret = fdt_pack(fdt);
869 			if (ret < 0) {
870 				fprintf(stderr, "Failed to pack: err=%d\n",
871 					ret);
872 				goto err;
873 			}
874 			size = fdt_totalsize(fdt);
875 		}
876 
877 		if (size != fwrite(fdt, 1, size, disp->fout)) {
878 			fprintf(stderr, "Write failure, %d bytes\n", size);
879 			free(fdt);
880 			ret = 1;
881 			goto err;
882 		}
883 		free(fdt);
884 	}
885 err:
886 	free(blob);
887 	free(region);
888 
889 	return ret;
890 }
891 
892 static const char usage_synopsis[] =
893 	"fdtgrep - extract portions from device tree\n"
894 	"\n"
895 	"Usage:\n"
896 	"	fdtgrep <options> <dt file>|-\n\n"
897 	"Output formats are:\n"
898 	"\tdts - device tree soure text\n"
899 	"\tdtb - device tree blob (sets -Hmt automatically)\n"
900 	"\tbin - device tree fragment (may not be a valid .dtb)";
901 
902 /* Helper for usage_short_opts string constant */
903 #define USAGE_COMMON_SHORT_OPTS "hV"
904 
905 /* Helper for aligning long_opts array */
906 #define a_argument required_argument
907 
908 /* Helper for usage_long_opts option array */
909 #define USAGE_COMMON_LONG_OPTS \
910 	{"help",      no_argument, NULL, 'h'}, \
911 	{"version",   no_argument, NULL, 'V'}, \
912 	{NULL,        no_argument, NULL, 0x0}
913 
914 /* Helper for usage_opts_help array */
915 #define USAGE_COMMON_OPTS_HELP \
916 	"Print this help and exit", \
917 	"Print version and exit", \
918 	NULL
919 
920 /* Helper for getopt case statements */
921 #define case_USAGE_COMMON_FLAGS \
922 	case 'h': usage(NULL); \
923 	case 'V': util_version(); \
924 	case '?': usage("unknown option");
925 
926 static const char usage_short_opts[] =
927 		"haAc:b:C:defg:G:HIlLmn:N:o:O:p:P:rRsStTv"
928 		USAGE_COMMON_SHORT_OPTS;
929 static struct option const usage_long_opts[] = {
930 	{"show-address",	no_argument, NULL, 'a'},
931 	{"colour",		no_argument, NULL, 'A'},
932 	{"include-node-with-prop", a_argument, NULL, 'b'},
933 	{"include-compat",	a_argument, NULL, 'c'},
934 	{"exclude-compat",	a_argument, NULL, 'C'},
935 	{"diff",		no_argument, NULL, 'd'},
936 	{"enter-node",		no_argument, NULL, 'e'},
937 	{"show-offset",		no_argument, NULL, 'f'},
938 	{"include-match",	a_argument, NULL, 'g'},
939 	{"exclude-match",	a_argument, NULL, 'G'},
940 	{"show-header",		no_argument, NULL, 'H'},
941 	{"show-version",	no_argument, NULL, 'I'},
942 	{"list-regions",	no_argument, NULL, 'l'},
943 	{"list-strings",	no_argument, NULL, 'L'},
944 	{"include-mem",		no_argument, NULL, 'm'},
945 	{"include-node",	a_argument, NULL, 'n'},
946 	{"exclude-node",	a_argument, NULL, 'N'},
947 	{"include-prop",	a_argument, NULL, 'p'},
948 	{"exclude-prop",	a_argument, NULL, 'P'},
949 	{"remove-strings",	no_argument, NULL, 'r'},
950 	{"include-root",	no_argument, NULL, 'R'},
951 	{"show-subnodes",	no_argument, NULL, 's'},
952 	{"skip-supernodes",	no_argument, NULL, 'S'},
953 	{"show-stringtab",	no_argument, NULL, 't'},
954 	{"show-aliases",	no_argument, NULL, 'T'},
955 	{"out",			a_argument, NULL, 'o'},
956 	{"out-format",		a_argument, NULL, 'O'},
957 	{"invert-match",	no_argument, NULL, 'v'},
958 	USAGE_COMMON_LONG_OPTS,
959 };
960 static const char * const usage_opts_help[] = {
961 	"Display address",
962 	"Show all nodes/tags, colour those that match",
963 	"Include contains containing property",
964 	"Compatible nodes to include in grep",
965 	"Compatible nodes to exclude in grep",
966 	"Diff: Mark matching nodes with +, others with -",
967 	"Enter direct subnode names of matching nodes",
968 	"Display offset",
969 	"Node/property/compatible string to include in grep",
970 	"Node/property/compatible string to exclude in grep",
971 	"Output a header",
972 	"Put \"/dts-v1/;\" on first line of dts output",
973 	"Output a region list",
974 	"List strings in string table",
975 	"Include mem_rsvmap section in binary output",
976 	"Node to include in grep",
977 	"Node to exclude in grep",
978 	"Property to include in grep",
979 	"Property to exclude in grep",
980 	"Remove unused strings from string table",
981 	"Include root node and all properties",
982 	"Show all subnodes matching nodes",
983 	"Don't include supernodes of matching nodes",
984 	"Include string table in binary output",
985 	"Include matching aliases in output",
986 	"-o <output file>",
987 	"-O <output format>",
988 	"Invert the sense of matching (select non-matching lines)",
989 	USAGE_COMMON_OPTS_HELP
990 };
991 
992 /**
993  * Call getopt_long() with standard options
994  *
995  * Since all util code runs getopt in the same way, provide a helper.
996  */
997 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
998 				       usage_long_opts, NULL)
999 
1000 void util_usage(const char *errmsg, const char *synopsis,
1001 		const char *short_opts, struct option const long_opts[],
1002 		const char * const opts_help[])
1003 {
1004 	FILE *fp = errmsg ? stderr : stdout;
1005 	const char a_arg[] = "<arg>";
1006 	size_t a_arg_len = strlen(a_arg) + 1;
1007 	size_t i;
1008 	int optlen;
1009 
1010 	fprintf(fp,
1011 		"Usage: %s\n"
1012 		"\n"
1013 		"Options: -[%s]\n", synopsis, short_opts);
1014 
1015 	/* prescan the --long opt length to auto-align */
1016 	optlen = 0;
1017 	for (i = 0; long_opts[i].name; ++i) {
1018 		/* +1 is for space between --opt and help text */
1019 		int l = strlen(long_opts[i].name) + 1;
1020 		if (long_opts[i].has_arg == a_argument)
1021 			l += a_arg_len;
1022 		if (optlen < l)
1023 			optlen = l;
1024 	}
1025 
1026 	for (i = 0; long_opts[i].name; ++i) {
1027 		/* helps when adding new applets or options */
1028 		assert(opts_help[i] != NULL);
1029 
1030 		/* first output the short flag if it has one */
1031 		if (long_opts[i].val > '~')
1032 			fprintf(fp, "      ");
1033 		else
1034 			fprintf(fp, "  -%c, ", long_opts[i].val);
1035 
1036 		/* then the long flag */
1037 		if (long_opts[i].has_arg == no_argument) {
1038 			fprintf(fp, "--%-*s", optlen, long_opts[i].name);
1039 		} else {
1040 			fprintf(fp, "--%s %s%*s", long_opts[i].name, a_arg,
1041 				(int)(optlen - strlen(long_opts[i].name) -
1042 				a_arg_len), "");
1043 		}
1044 
1045 		/* finally the help text */
1046 		fprintf(fp, "%s\n", opts_help[i]);
1047 	}
1048 
1049 	if (errmsg) {
1050 		fprintf(fp, "\nError: %s\n", errmsg);
1051 		exit(EXIT_FAILURE);
1052 	} else {
1053 		exit(EXIT_SUCCESS);
1054 	}
1055 }
1056 
1057 /**
1058  * Show usage and exit
1059  *
1060  * If you name all your usage variables with usage_xxx, then you can call this
1061  * help macro rather than expanding all arguments yourself.
1062  *
1063  * @param errmsg	If non-NULL, an error message to display
1064  */
1065 #define usage(errmsg) \
1066 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
1067 		   usage_long_opts, usage_opts_help)
1068 
1069 void util_version(void)
1070 {
1071 	printf("Version: %s\n", "(U-Boot)");
1072 	exit(0);
1073 }
1074 
1075 static void scan_args(struct display_info *disp, int argc, char *argv[])
1076 {
1077 	int opt;
1078 
1079 	while ((opt = util_getopt_long()) != EOF) {
1080 		int type = 0;
1081 		int inc = 1;
1082 
1083 		switch (opt) {
1084 		case_USAGE_COMMON_FLAGS
1085 		case 'a':
1086 			disp->show_addr = 1;
1087 			break;
1088 		case 'A':
1089 			disp->all = 1;
1090 			break;
1091 		case 'b':
1092 			type = FDT_NODE_HAS_PROP;
1093 			break;
1094 		case 'C':
1095 			inc = 0;
1096 			/* no break */
1097 		case 'c':
1098 			type = FDT_IS_COMPAT;
1099 			break;
1100 		case 'd':
1101 			disp->diff = 1;
1102 			break;
1103 		case 'e':
1104 			disp->flags |= FDT_REG_DIRECT_SUBNODES;
1105 			break;
1106 		case 'f':
1107 			disp->show_offset = 1;
1108 			break;
1109 		case 'G':
1110 			inc = 0;
1111 			/* no break */
1112 		case 'g':
1113 			type = FDT_ANY_GLOBAL;
1114 			break;
1115 		case 'H':
1116 			disp->header = 1;
1117 			break;
1118 		case 'l':
1119 			disp->region_list = 1;
1120 			break;
1121 		case 'L':
1122 			disp->list_strings = 1;
1123 			break;
1124 		case 'm':
1125 			disp->flags |= FDT_REG_ADD_MEM_RSVMAP;
1126 			break;
1127 		case 'N':
1128 			inc = 0;
1129 			/* no break */
1130 		case 'n':
1131 			type = FDT_IS_NODE;
1132 			break;
1133 		case 'o':
1134 			disp->output_fname = optarg;
1135 			break;
1136 		case 'O':
1137 			if (!strcmp(optarg, "dtb"))
1138 				disp->output = OUT_DTB;
1139 			else if (!strcmp(optarg, "dts"))
1140 				disp->output = OUT_DTS;
1141 			else if (!strcmp(optarg, "bin"))
1142 				disp->output = OUT_BIN;
1143 			else
1144 				usage("Unknown output format");
1145 			break;
1146 		case 'P':
1147 			inc = 0;
1148 			/* no break */
1149 		case 'p':
1150 			type = FDT_IS_PROP;
1151 			break;
1152 		case 'r':
1153 			disp->remove_strings = 1;
1154 			break;
1155 		case 'R':
1156 			disp->include_root = 1;
1157 			break;
1158 		case 's':
1159 			disp->flags |= FDT_REG_ALL_SUBNODES;
1160 			break;
1161 		case 'S':
1162 			disp->flags &= ~FDT_REG_SUPERNODES;
1163 			break;
1164 		case 't':
1165 			disp->flags |= FDT_REG_ADD_STRING_TAB;
1166 			break;
1167 		case 'T':
1168 			disp->add_aliases = 1;
1169 			break;
1170 		case 'v':
1171 			disp->invert = 1;
1172 			break;
1173 		case 'I':
1174 			disp->show_dts_version = 1;
1175 			break;
1176 		}
1177 
1178 		if (type && value_add(disp, &disp->value_head, type, inc,
1179 				      optarg))
1180 			usage("Cannot add value");
1181 	}
1182 
1183 	if (disp->invert && disp->types_exc)
1184 		usage("-v has no meaning when used with 'exclude' conditions");
1185 }
1186 
1187 int main(int argc, char *argv[])
1188 {
1189 	char *filename = NULL;
1190 	struct display_info disp;
1191 	int ret;
1192 
1193 	/* set defaults */
1194 	memset(&disp, '\0', sizeof(disp));
1195 	disp.flags = FDT_REG_SUPERNODES;	/* Default flags */
1196 
1197 	scan_args(&disp, argc, argv);
1198 
1199 	/* Show matched lines in colour if we can */
1200 	disp.colour = disp.all && isatty(0);
1201 
1202 	/* Any additional arguments can match anything, just like -g */
1203 	while (optind < argc - 1) {
1204 		if (value_add(&disp, &disp.value_head, FDT_IS_ANY, 1,
1205 			      argv[optind++]))
1206 			usage("Cannot add value");
1207 	}
1208 
1209 	if (optind < argc)
1210 		filename = argv[optind++];
1211 	if (!filename)
1212 		usage("Missing filename");
1213 
1214 	/* If a valid .dtb is required, set flags to ensure we get one */
1215 	if (disp.output == OUT_DTB) {
1216 		disp.header = 1;
1217 		disp.flags |= FDT_REG_ADD_MEM_RSVMAP | FDT_REG_ADD_STRING_TAB;
1218 	}
1219 
1220 	if (disp.output_fname) {
1221 		disp.fout = fopen(disp.output_fname, "w");
1222 		if (!disp.fout)
1223 			usage("Cannot open output file");
1224 	} else {
1225 		disp.fout = stdout;
1226 	}
1227 
1228 	/* Run the grep and output the results */
1229 	ret = do_fdtgrep(&disp, filename);
1230 	if (disp.output_fname)
1231 		fclose(disp.fout);
1232 	if (ret)
1233 		return 1;
1234 
1235 	return 0;
1236 }
1237