xref: /rk3399_rockchip-uboot/tools/env/fw_env.c (revision 30fd4fadb319d7c6d43d949e2d30ffaea46a60cf)
1 /*
2  * (C) Copyright 2000-2010
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * (C) Copyright 2008
6  * Guennadi Liakhovetski, DENX Software Engineering, lg@denx.de.
7  *
8  * See file CREDITS for list of people who contributed to this
9  * project.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License as
13  * published by the Free Software Foundation; either version 2 of
14  * the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24  * MA 02111-1307 USA
25  */
26 
27 #include <errno.h>
28 #include <env_flags.h>
29 #include <fcntl.h>
30 #include <linux/stringify.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <stddef.h>
34 #include <string.h>
35 #include <sys/types.h>
36 #include <sys/ioctl.h>
37 #include <sys/stat.h>
38 #include <unistd.h>
39 
40 #ifdef MTD_OLD
41 # include <stdint.h>
42 # include <linux/mtd/mtd.h>
43 #else
44 # define  __user	/* nothing */
45 # include <mtd/mtd-user.h>
46 #endif
47 
48 #include "fw_env.h"
49 
50 #define WHITESPACE(c) ((c == '\t') || (c == ' '))
51 
52 #define min(x, y) ({				\
53 	typeof(x) _min1 = (x);			\
54 	typeof(y) _min2 = (y);			\
55 	(void) (&_min1 == &_min2);		\
56 	_min1 < _min2 ? _min1 : _min2; })
57 
58 struct envdev_s {
59 	char devname[16];		/* Device name */
60 	ulong devoff;			/* Device offset */
61 	ulong env_size;			/* environment size */
62 	ulong erase_size;		/* device erase size */
63 	ulong env_sectors;		/* number of environment sectors */
64 	uint8_t mtd_type;		/* type of the MTD device */
65 };
66 
67 static struct envdev_s envdevices[2] =
68 {
69 	{
70 		.mtd_type = MTD_ABSENT,
71 	}, {
72 		.mtd_type = MTD_ABSENT,
73 	},
74 };
75 static int dev_current;
76 
77 #define DEVNAME(i)    envdevices[(i)].devname
78 #define DEVOFFSET(i)  envdevices[(i)].devoff
79 #define ENVSIZE(i)    envdevices[(i)].env_size
80 #define DEVESIZE(i)   envdevices[(i)].erase_size
81 #define ENVSECTORS(i) envdevices[(i)].env_sectors
82 #define DEVTYPE(i)    envdevices[(i)].mtd_type
83 
84 #define CUR_ENVSIZE ENVSIZE(dev_current)
85 
86 #define ENV_SIZE      getenvsize()
87 
88 struct env_image_single {
89 	uint32_t	crc;	/* CRC32 over data bytes    */
90 	char		data[];
91 };
92 
93 struct env_image_redundant {
94 	uint32_t	crc;	/* CRC32 over data bytes    */
95 	unsigned char	flags;	/* active or obsolete */
96 	char		data[];
97 };
98 
99 enum flag_scheme {
100 	FLAG_NONE,
101 	FLAG_BOOLEAN,
102 	FLAG_INCREMENTAL,
103 };
104 
105 struct environment {
106 	void			*image;
107 	uint32_t		*crc;
108 	unsigned char		*flags;
109 	char			*data;
110 	enum flag_scheme	flag_scheme;
111 };
112 
113 static struct environment environment = {
114 	.flag_scheme = FLAG_NONE,
115 };
116 
117 static int HaveRedundEnv = 0;
118 
119 static unsigned char active_flag = 1;
120 /* obsolete_flag must be 0 to efficiently set it on NOR flash without erasing */
121 static unsigned char obsolete_flag = 0;
122 
123 #define DEFAULT_ENV_INSTANCE_STATIC
124 #include <env_default.h>
125 
126 static int flash_io (int mode);
127 static char *envmatch (char * s1, char * s2);
128 static int parse_config (void);
129 
130 #if defined(CONFIG_FILE)
131 static int get_config (char *);
132 #endif
133 static inline ulong getenvsize (void)
134 {
135 	ulong rc = CUR_ENVSIZE - sizeof(long);
136 
137 	if (HaveRedundEnv)
138 		rc -= sizeof (char);
139 	return rc;
140 }
141 
142 static char *fw_string_blank(char *s, int noblank)
143 {
144 	int i;
145 	int len = strlen(s);
146 
147 	for (i = 0; i < len; i++, s++) {
148 		if ((noblank && !WHITESPACE(*s)) ||
149 			(!noblank && WHITESPACE(*s)))
150 			break;
151 	}
152 	if (i == len)
153 		return NULL;
154 
155 	return s;
156 }
157 
158 /*
159  * Search the environment for a variable.
160  * Return the value, if found, or NULL, if not found.
161  */
162 char *fw_getenv (char *name)
163 {
164 	char *env, *nxt;
165 
166 	for (env = environment.data; *env; env = nxt + 1) {
167 		char *val;
168 
169 		for (nxt = env; *nxt; ++nxt) {
170 			if (nxt >= &environment.data[ENV_SIZE]) {
171 				fprintf (stderr, "## Error: "
172 					"environment not terminated\n");
173 				return NULL;
174 			}
175 		}
176 		val = envmatch (name, env);
177 		if (!val)
178 			continue;
179 		return val;
180 	}
181 	return NULL;
182 }
183 
184 /*
185  * Print the current definition of one, or more, or all
186  * environment variables
187  */
188 int fw_printenv (int argc, char *argv[])
189 {
190 	char *env, *nxt;
191 	int i, n_flag;
192 	int rc = 0;
193 
194 	if (fw_env_open())
195 		return -1;
196 
197 	if (argc == 1) {		/* Print all env variables  */
198 		for (env = environment.data; *env; env = nxt + 1) {
199 			for (nxt = env; *nxt; ++nxt) {
200 				if (nxt >= &environment.data[ENV_SIZE]) {
201 					fprintf (stderr, "## Error: "
202 						"environment not terminated\n");
203 					return -1;
204 				}
205 			}
206 
207 			printf ("%s\n", env);
208 		}
209 		return 0;
210 	}
211 
212 	if (strcmp (argv[1], "-n") == 0) {
213 		n_flag = 1;
214 		++argv;
215 		--argc;
216 		if (argc != 2) {
217 			fprintf (stderr, "## Error: "
218 				"`-n' option requires exactly one argument\n");
219 			return -1;
220 		}
221 	} else {
222 		n_flag = 0;
223 	}
224 
225 	for (i = 1; i < argc; ++i) {	/* print single env variables   */
226 		char *name = argv[i];
227 		char *val = NULL;
228 
229 		for (env = environment.data; *env; env = nxt + 1) {
230 
231 			for (nxt = env; *nxt; ++nxt) {
232 				if (nxt >= &environment.data[ENV_SIZE]) {
233 					fprintf (stderr, "## Error: "
234 						"environment not terminated\n");
235 					return -1;
236 				}
237 			}
238 			val = envmatch (name, env);
239 			if (val) {
240 				if (!n_flag) {
241 					fputs (name, stdout);
242 					putc ('=', stdout);
243 				}
244 				puts (val);
245 				break;
246 			}
247 		}
248 		if (!val) {
249 			fprintf (stderr, "## Error: \"%s\" not defined\n", name);
250 			rc = -1;
251 		}
252 	}
253 
254 	return rc;
255 }
256 
257 int fw_env_close(void)
258 {
259 	/*
260 	 * Update CRC
261 	 */
262 	*environment.crc = crc32(0, (uint8_t *) environment.data, ENV_SIZE);
263 
264 	/* write environment back to flash */
265 	if (flash_io(O_RDWR)) {
266 		fprintf(stderr,
267 			"Error: can't write fw_env to flash\n");
268 			return -1;
269 	}
270 
271 	return 0;
272 }
273 
274 
275 /*
276  * Set/Clear a single variable in the environment.
277  * This is called in sequence to update the environment
278  * in RAM without updating the copy in flash after each set
279  */
280 int fw_env_write(char *name, char *value)
281 {
282 	int len;
283 	char *env, *nxt;
284 	char *oldval = NULL;
285 
286 	/*
287 	 * search if variable with this name already exists
288 	 */
289 	for (nxt = env = environment.data; *env; env = nxt + 1) {
290 		for (nxt = env; *nxt; ++nxt) {
291 			if (nxt >= &environment.data[ENV_SIZE]) {
292 				fprintf(stderr, "## Error: "
293 					"environment not terminated\n");
294 				errno = EINVAL;
295 				return -1;
296 			}
297 		}
298 		if ((oldval = envmatch (name, env)) != NULL)
299 			break;
300 	}
301 
302 	/*
303 	 * Delete any existing definition
304 	 */
305 	if (oldval) {
306 #ifndef CONFIG_ENV_OVERWRITE
307 		/*
308 		 * Ethernet Address and serial# can be set only once
309 		 */
310 		if (
311 		    (strcmp(name, "serial#") == 0) ||
312 		    ((strcmp(name, "ethaddr") == 0)
313 #if defined(CONFIG_OVERWRITE_ETHADDR_ONCE) && defined(CONFIG_ETHADDR)
314 		    && (strcmp(oldval, __stringify(CONFIG_ETHADDR)) != 0)
315 #endif /* CONFIG_OVERWRITE_ETHADDR_ONCE && CONFIG_ETHADDR */
316 		   ) ) {
317 			fprintf (stderr, "Can't overwrite \"%s\"\n", name);
318 			errno = EROFS;
319 			return -1;
320 		}
321 #endif /* CONFIG_ENV_OVERWRITE */
322 
323 		if (*++nxt == '\0') {
324 			*env = '\0';
325 		} else {
326 			for (;;) {
327 				*env = *nxt++;
328 				if ((*env == '\0') && (*nxt == '\0'))
329 					break;
330 				++env;
331 			}
332 		}
333 		*++env = '\0';
334 	}
335 
336 	/* Delete only ? */
337 	if (!value || !strlen(value))
338 		return 0;
339 
340 	/*
341 	 * Append new definition at the end
342 	 */
343 	for (env = environment.data; *env || *(env + 1); ++env);
344 	if (env > environment.data)
345 		++env;
346 	/*
347 	 * Overflow when:
348 	 * "name" + "=" + "val" +"\0\0"  > CUR_ENVSIZE - (env-environment)
349 	 */
350 	len = strlen (name) + 2;
351 	/* add '=' for first arg, ' ' for all others */
352 	len += strlen(value) + 1;
353 
354 	if (len > (&environment.data[ENV_SIZE] - env)) {
355 		fprintf (stderr,
356 			"Error: environment overflow, \"%s\" deleted\n",
357 			name);
358 		return -1;
359 	}
360 
361 	while ((*env = *name++) != '\0')
362 		env++;
363 	*env = '=';
364 	while ((*++env = *value++) != '\0')
365 		;
366 
367 	/* end is marked with double '\0' */
368 	*++env = '\0';
369 
370 	return 0;
371 }
372 
373 /*
374  * Deletes or sets environment variables. Returns -1 and sets errno error codes:
375  * 0	  - OK
376  * EINVAL - need at least 1 argument
377  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
378  *	    modified or deleted
379  *
380  */
381 int fw_setenv(int argc, char *argv[])
382 {
383 	int i, len;
384 	char *name;
385 	char *value = NULL;
386 
387 	if (argc < 2) {
388 		errno = EINVAL;
389 		return -1;
390 	}
391 
392 	if (fw_env_open()) {
393 		fprintf(stderr, "Error: environment not initialized\n");
394 		return -1;
395 	}
396 
397 	name = argv[1];
398 
399 	if (env_flags_validate_env_set_params(argc, argv) < 0)
400 		return 1;
401 
402 	len = 0;
403 	for (i = 2; i < argc; ++i) {
404 		char *val = argv[i];
405 		size_t val_len = strlen(val);
406 
407 		if (value)
408 			value[len - 1] = ' ';
409 		value = realloc(value, len + val_len + 1);
410 		if (!value) {
411 			fprintf(stderr,
412 				"Cannot malloc %zu bytes: %s\n",
413 				len, strerror(errno));
414 			return -1;
415 		}
416 
417 		memcpy(value + len, val, val_len);
418 		len += val_len;
419 		value[len++] = '\0';
420 	}
421 
422 	fw_env_write(name, value);
423 
424 	free(value);
425 
426 	return fw_env_close();
427 }
428 
429 /*
430  * Parse  a file  and configure the u-boot variables.
431  * The script file has a very simple format, as follows:
432  *
433  * Each line has a couple with name, value:
434  * <white spaces>variable_name<white spaces>variable_value
435  *
436  * Both variable_name and variable_value are interpreted as strings.
437  * Any character after <white spaces> and before ending \r\n is interpreted
438  * as variable's value (no comment allowed on these lines !)
439  *
440  * Comments are allowed if the first character in the line is #
441  *
442  * Returns -1 and sets errno error codes:
443  * 0	  - OK
444  * -1     - Error
445  */
446 int fw_parse_script(char *fname)
447 {
448 	FILE *fp;
449 	char dump[1024];	/* Maximum line length in the file */
450 	char *name;
451 	char *val;
452 	int lineno = 0;
453 	int len;
454 	int ret = 0;
455 
456 	if (fw_env_open()) {
457 		fprintf(stderr, "Error: environment not initialized\n");
458 		return -1;
459 	}
460 
461 	if (strcmp(fname, "-") == 0)
462 		fp = stdin;
463 	else {
464 		fp = fopen(fname, "r");
465 		if (fp == NULL) {
466 			fprintf(stderr, "I cannot open %s for reading\n",
467 				 fname);
468 			return -1;
469 		}
470 	}
471 
472 	while (fgets(dump, sizeof(dump), fp)) {
473 		lineno++;
474 		len = strlen(dump);
475 
476 		/*
477 		 * Read a whole line from the file. If the line is too long
478 		 * or is not terminated, reports an error and exit.
479 		 */
480 		if (dump[len - 1] != '\n') {
481 			fprintf(stderr,
482 			"Line %d not corrected terminated or too long\n",
483 				lineno);
484 			ret = -1;
485 			break;
486 		}
487 
488 		/* Drop ending line feed / carriage return */
489 		while (len > 0 && (dump[len - 1] == '\n' ||
490 				dump[len - 1] == '\r')) {
491 			dump[len - 1] = '\0';
492 			len--;
493 		}
494 
495 		/* Skip comment or empty lines */
496 		if ((len == 0) || dump[0] == '#')
497 			continue;
498 
499 		/*
500 		 * Search for variable's name,
501 		 * remove leading whitespaces
502 		 */
503 		name = fw_string_blank(dump, 1);
504 		if (!name)
505 			continue;
506 
507 		/* The first white space is the end of variable name */
508 		val = fw_string_blank(name, 0);
509 		len = strlen(name);
510 		if (val) {
511 			*val++ = '\0';
512 			if ((val - name) < len)
513 				val = fw_string_blank(val, 1);
514 			else
515 				val = NULL;
516 		}
517 
518 #ifdef DEBUG
519 		fprintf(stderr, "Setting %s : %s\n",
520 			name, val ? val : " removed");
521 #endif
522 
523 		if (env_flags_validate_type(name, val) < 0) {
524 			ret = -1;
525 			break;
526 		}
527 
528 		/*
529 		 * If there is an error setting a variable,
530 		 * try to save the environment and returns an error
531 		 */
532 		if (fw_env_write(name, val)) {
533 			fprintf(stderr,
534 			"fw_env_write returns with error : %s\n",
535 				strerror(errno));
536 			ret = -1;
537 			break;
538 		}
539 
540 	}
541 
542 	/* Close file if not stdin */
543 	if (strcmp(fname, "-") != 0)
544 		fclose(fp);
545 
546 	ret |= fw_env_close();
547 
548 	return ret;
549 
550 }
551 
552 /*
553  * Test for bad block on NAND, just returns 0 on NOR, on NAND:
554  * 0	- block is good
555  * > 0	- block is bad
556  * < 0	- failed to test
557  */
558 static int flash_bad_block (int fd, uint8_t mtd_type, loff_t *blockstart)
559 {
560 	if (mtd_type == MTD_NANDFLASH) {
561 		int badblock = ioctl (fd, MEMGETBADBLOCK, blockstart);
562 
563 		if (badblock < 0) {
564 			perror ("Cannot read bad block mark");
565 			return badblock;
566 		}
567 
568 		if (badblock) {
569 #ifdef DEBUG
570 			fprintf (stderr, "Bad block at 0x%llx, "
571 				 "skipping\n", *blockstart);
572 #endif
573 			return badblock;
574 		}
575 	}
576 
577 	return 0;
578 }
579 
580 /*
581  * Read data from flash at an offset into a provided buffer. On NAND it skips
582  * bad blocks but makes sure it stays within ENVSECTORS (dev) starting from
583  * the DEVOFFSET (dev) block. On NOR the loop is only run once.
584  */
585 static int flash_read_buf (int dev, int fd, void *buf, size_t count,
586 			   off_t offset, uint8_t mtd_type)
587 {
588 	size_t blocklen;	/* erase / write length - one block on NAND,
589 				   0 on NOR */
590 	size_t processed = 0;	/* progress counter */
591 	size_t readlen = count;	/* current read length */
592 	off_t top_of_range;	/* end of the last block we may use */
593 	off_t block_seek;	/* offset inside the current block to the start
594 				   of the data */
595 	loff_t blockstart;	/* running start of the current block -
596 				   MEMGETBADBLOCK needs 64 bits */
597 	int rc;
598 
599 	blockstart = (offset / DEVESIZE (dev)) * DEVESIZE (dev);
600 
601 	/* Offset inside a block */
602 	block_seek = offset - blockstart;
603 
604 	if (mtd_type == MTD_NANDFLASH) {
605 		/*
606 		 * NAND: calculate which blocks we are reading. We have
607 		 * to read one block at a time to skip bad blocks.
608 		 */
609 		blocklen = DEVESIZE (dev);
610 
611 		/*
612 		 * To calculate the top of the range, we have to use the
613 		 * global DEVOFFSET (dev), which can be different from offset
614 		 */
615 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
616 				ENVSECTORS (dev)) * blocklen;
617 
618 		/* Limit to one block for the first read */
619 		if (readlen > blocklen - block_seek)
620 			readlen = blocklen - block_seek;
621 	} else {
622 		blocklen = 0;
623 		top_of_range = offset + count;
624 	}
625 
626 	/* This only runs once on NOR flash */
627 	while (processed < count) {
628 		rc = flash_bad_block (fd, mtd_type, &blockstart);
629 		if (rc < 0)		/* block test failed */
630 			return -1;
631 
632 		if (blockstart + block_seek + readlen > top_of_range) {
633 			/* End of range is reached */
634 			fprintf (stderr,
635 				 "Too few good blocks within range\n");
636 			return -1;
637 		}
638 
639 		if (rc) {		/* block is bad */
640 			blockstart += blocklen;
641 			continue;
642 		}
643 
644 		/*
645 		 * If a block is bad, we retry in the next block at the same
646 		 * offset - see common/env_nand.c::writeenv()
647 		 */
648 		lseek (fd, blockstart + block_seek, SEEK_SET);
649 
650 		rc = read (fd, buf + processed, readlen);
651 		if (rc != readlen) {
652 			fprintf (stderr, "Read error on %s: %s\n",
653 				 DEVNAME (dev), strerror (errno));
654 			return -1;
655 		}
656 #ifdef DEBUG
657 		fprintf(stderr, "Read 0x%x bytes at 0x%llx on %s\n",
658 			 rc, blockstart + block_seek, DEVNAME(dev));
659 #endif
660 		processed += readlen;
661 		readlen = min (blocklen, count - processed);
662 		block_seek = 0;
663 		blockstart += blocklen;
664 	}
665 
666 	return processed;
667 }
668 
669 /*
670  * Write count bytes at offset, but stay within ENVSECTORS (dev) sectors of
671  * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
672  * erase and write the whole data at once.
673  */
674 static int flash_write_buf (int dev, int fd, void *buf, size_t count,
675 			    off_t offset, uint8_t mtd_type)
676 {
677 	void *data;
678 	struct erase_info_user erase;
679 	size_t blocklen;	/* length of NAND block / NOR erase sector */
680 	size_t erase_len;	/* whole area that can be erased - may include
681 				   bad blocks */
682 	size_t erasesize;	/* erase / write length - one block on NAND,
683 				   whole area on NOR */
684 	size_t processed = 0;	/* progress counter */
685 	size_t write_total;	/* total size to actually write - excluding
686 				   bad blocks */
687 	off_t erase_offset;	/* offset to the first erase block (aligned)
688 				   below offset */
689 	off_t block_seek;	/* offset inside the erase block to the start
690 				   of the data */
691 	off_t top_of_range;	/* end of the last block we may use */
692 	loff_t blockstart;	/* running start of the current block -
693 				   MEMGETBADBLOCK needs 64 bits */
694 	int rc;
695 
696 	blocklen = DEVESIZE (dev);
697 
698 	top_of_range = ((DEVOFFSET(dev) / blocklen) +
699 					ENVSECTORS (dev)) * blocklen;
700 
701 	erase_offset = (offset / blocklen) * blocklen;
702 
703 	/* Maximum area we may use */
704 	erase_len = top_of_range - erase_offset;
705 
706 	blockstart = erase_offset;
707 	/* Offset inside a block */
708 	block_seek = offset - erase_offset;
709 
710 	/*
711 	 * Data size we actually have to write: from the start of the block
712 	 * to the start of the data, then count bytes of data, and to the
713 	 * end of the block
714 	 */
715 	write_total = ((block_seek + count + blocklen - 1) /
716 						blocklen) * blocklen;
717 
718 	/*
719 	 * Support data anywhere within erase sectors: read out the complete
720 	 * area to be erased, replace the environment image, write the whole
721 	 * block back again.
722 	 */
723 	if (write_total > count) {
724 		data = malloc (erase_len);
725 		if (!data) {
726 			fprintf (stderr,
727 				 "Cannot malloc %zu bytes: %s\n",
728 				 erase_len, strerror (errno));
729 			return -1;
730 		}
731 
732 		rc = flash_read_buf (dev, fd, data, write_total, erase_offset,
733 				     mtd_type);
734 		if (write_total != rc)
735 			return -1;
736 
737 #ifdef DEBUG
738 		fprintf(stderr, "Preserving data ");
739 		if (block_seek != 0)
740 			fprintf(stderr, "0x%x - 0x%lx", 0, block_seek - 1);
741 		if (block_seek + count != write_total) {
742 			if (block_seek != 0)
743 				fprintf(stderr, " and ");
744 			fprintf(stderr, "0x%lx - 0x%x",
745 				block_seek + count, write_total - 1);
746 		}
747 		fprintf(stderr, "\n");
748 #endif
749 		/* Overwrite the old environment */
750 		memcpy (data + block_seek, buf, count);
751 	} else {
752 		/*
753 		 * We get here, iff offset is block-aligned and count is a
754 		 * multiple of blocklen - see write_total calculation above
755 		 */
756 		data = buf;
757 	}
758 
759 	if (mtd_type == MTD_NANDFLASH) {
760 		/*
761 		 * NAND: calculate which blocks we are writing. We have
762 		 * to write one block at a time to skip bad blocks.
763 		 */
764 		erasesize = blocklen;
765 	} else {
766 		erasesize = erase_len;
767 	}
768 
769 	erase.length = erasesize;
770 
771 	/* This only runs once on NOR flash and SPI-dataflash */
772 	while (processed < write_total) {
773 		rc = flash_bad_block (fd, mtd_type, &blockstart);
774 		if (rc < 0)		/* block test failed */
775 			return rc;
776 
777 		if (blockstart + erasesize > top_of_range) {
778 			fprintf (stderr, "End of range reached, aborting\n");
779 			return -1;
780 		}
781 
782 		if (rc) {		/* block is bad */
783 			blockstart += blocklen;
784 			continue;
785 		}
786 
787 		erase.start = blockstart;
788 		ioctl (fd, MEMUNLOCK, &erase);
789 
790 		/* Dataflash does not need an explicit erase cycle */
791 		if (mtd_type != MTD_DATAFLASH)
792 			if (ioctl (fd, MEMERASE, &erase) != 0) {
793 				fprintf (stderr, "MTD erase error on %s: %s\n",
794 					 DEVNAME (dev),
795 					 strerror (errno));
796 				return -1;
797 			}
798 
799 		if (lseek (fd, blockstart, SEEK_SET) == -1) {
800 			fprintf (stderr,
801 				 "Seek error on %s: %s\n",
802 				 DEVNAME (dev), strerror (errno));
803 			return -1;
804 		}
805 
806 #ifdef DEBUG
807 		fprintf(stderr, "Write 0x%x bytes at 0x%llx\n", erasesize,
808 			blockstart);
809 #endif
810 		if (write (fd, data + processed, erasesize) != erasesize) {
811 			fprintf (stderr, "Write error on %s: %s\n",
812 				 DEVNAME (dev), strerror (errno));
813 			return -1;
814 		}
815 
816 		ioctl (fd, MEMLOCK, &erase);
817 
818 		processed  += blocklen;
819 		block_seek = 0;
820 		blockstart += blocklen;
821 	}
822 
823 	if (write_total > count)
824 		free (data);
825 
826 	return processed;
827 }
828 
829 /*
830  * Set obsolete flag at offset - NOR flash only
831  */
832 static int flash_flag_obsolete (int dev, int fd, off_t offset)
833 {
834 	int rc;
835 	struct erase_info_user erase;
836 
837 	erase.start  = DEVOFFSET (dev);
838 	erase.length = DEVESIZE (dev);
839 	/* This relies on the fact, that obsolete_flag == 0 */
840 	rc = lseek (fd, offset, SEEK_SET);
841 	if (rc < 0) {
842 		fprintf (stderr, "Cannot seek to set the flag on %s \n",
843 			 DEVNAME (dev));
844 		return rc;
845 	}
846 	ioctl (fd, MEMUNLOCK, &erase);
847 	rc = write (fd, &obsolete_flag, sizeof (obsolete_flag));
848 	ioctl (fd, MEMLOCK, &erase);
849 	if (rc < 0)
850 		perror ("Could not set obsolete flag");
851 
852 	return rc;
853 }
854 
855 static int flash_write (int fd_current, int fd_target, int dev_target)
856 {
857 	int rc;
858 
859 	switch (environment.flag_scheme) {
860 	case FLAG_NONE:
861 		break;
862 	case FLAG_INCREMENTAL:
863 		(*environment.flags)++;
864 		break;
865 	case FLAG_BOOLEAN:
866 		*environment.flags = active_flag;
867 		break;
868 	default:
869 		fprintf (stderr, "Unimplemented flash scheme %u \n",
870 			 environment.flag_scheme);
871 		return -1;
872 	}
873 
874 #ifdef DEBUG
875 	fprintf(stderr, "Writing new environment at 0x%lx on %s\n",
876 		DEVOFFSET (dev_target), DEVNAME (dev_target));
877 #endif
878 	rc = flash_write_buf(dev_target, fd_target, environment.image,
879 			      CUR_ENVSIZE, DEVOFFSET(dev_target),
880 			      DEVTYPE(dev_target));
881 	if (rc < 0)
882 		return rc;
883 
884 	if (environment.flag_scheme == FLAG_BOOLEAN) {
885 		/* Have to set obsolete flag */
886 		off_t offset = DEVOFFSET (dev_current) +
887 			offsetof (struct env_image_redundant, flags);
888 #ifdef DEBUG
889 		fprintf(stderr,
890 			"Setting obsolete flag in environment at 0x%lx on %s\n",
891 			DEVOFFSET (dev_current), DEVNAME (dev_current));
892 #endif
893 		flash_flag_obsolete (dev_current, fd_current, offset);
894 	}
895 
896 	return 0;
897 }
898 
899 static int flash_read (int fd)
900 {
901 	struct mtd_info_user mtdinfo;
902 	int rc;
903 
904 	rc = ioctl (fd, MEMGETINFO, &mtdinfo);
905 	if (rc < 0) {
906 		perror ("Cannot get MTD information");
907 		return -1;
908 	}
909 
910 	if (mtdinfo.type != MTD_NORFLASH &&
911 	    mtdinfo.type != MTD_NANDFLASH &&
912 	    mtdinfo.type != MTD_DATAFLASH) {
913 		fprintf (stderr, "Unsupported flash type %u\n", mtdinfo.type);
914 		return -1;
915 	}
916 
917 	DEVTYPE(dev_current) = mtdinfo.type;
918 
919 	rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
920 			     DEVOFFSET (dev_current), mtdinfo.type);
921 
922 	return (rc != CUR_ENVSIZE) ? -1 : 0;
923 }
924 
925 static int flash_io (int mode)
926 {
927 	int fd_current, fd_target, rc, dev_target;
928 
929 	/* dev_current: fd_current, erase_current */
930 	fd_current = open (DEVNAME (dev_current), mode);
931 	if (fd_current < 0) {
932 		fprintf (stderr,
933 			 "Can't open %s: %s\n",
934 			 DEVNAME (dev_current), strerror (errno));
935 		return -1;
936 	}
937 
938 	if (mode == O_RDWR) {
939 		if (HaveRedundEnv) {
940 			/* switch to next partition for writing */
941 			dev_target = !dev_current;
942 			/* dev_target: fd_target, erase_target */
943 			fd_target = open (DEVNAME (dev_target), mode);
944 			if (fd_target < 0) {
945 				fprintf (stderr,
946 					 "Can't open %s: %s\n",
947 					 DEVNAME (dev_target),
948 					 strerror (errno));
949 				rc = -1;
950 				goto exit;
951 			}
952 		} else {
953 			dev_target = dev_current;
954 			fd_target = fd_current;
955 		}
956 
957 		rc = flash_write (fd_current, fd_target, dev_target);
958 
959 		if (HaveRedundEnv) {
960 			if (close (fd_target)) {
961 				fprintf (stderr,
962 					"I/O error on %s: %s\n",
963 					DEVNAME (dev_target),
964 					strerror (errno));
965 				rc = -1;
966 			}
967 		}
968 	} else {
969 		rc = flash_read (fd_current);
970 	}
971 
972 exit:
973 	if (close (fd_current)) {
974 		fprintf (stderr,
975 			 "I/O error on %s: %s\n",
976 			 DEVNAME (dev_current), strerror (errno));
977 		return -1;
978 	}
979 
980 	return rc;
981 }
982 
983 /*
984  * s1 is either a simple 'name', or a 'name=value' pair.
985  * s2 is a 'name=value' pair.
986  * If the names match, return the value of s2, else NULL.
987  */
988 
989 static char *envmatch (char * s1, char * s2)
990 {
991 	if (s1 == NULL || s2 == NULL)
992 		return NULL;
993 
994 	while (*s1 == *s2++)
995 		if (*s1++ == '=')
996 			return s2;
997 	if (*s1 == '\0' && *(s2 - 1) == '=')
998 		return s2;
999 	return NULL;
1000 }
1001 
1002 /*
1003  * Prevent confusion if running from erased flash memory
1004  */
1005 int fw_env_open(void)
1006 {
1007 	int crc0, crc0_ok;
1008 	unsigned char flag0;
1009 	void *addr0;
1010 
1011 	int crc1, crc1_ok;
1012 	unsigned char flag1;
1013 	void *addr1;
1014 
1015 	struct env_image_single *single;
1016 	struct env_image_redundant *redundant;
1017 
1018 	if (parse_config ())		/* should fill envdevices */
1019 		return -1;
1020 
1021 	addr0 = calloc(1, CUR_ENVSIZE);
1022 	if (addr0 == NULL) {
1023 		fprintf(stderr,
1024 			"Not enough memory for environment (%ld bytes)\n",
1025 			CUR_ENVSIZE);
1026 		return -1;
1027 	}
1028 
1029 	/* read environment from FLASH to local buffer */
1030 	environment.image = addr0;
1031 
1032 	if (HaveRedundEnv) {
1033 		redundant = addr0;
1034 		environment.crc		= &redundant->crc;
1035 		environment.flags	= &redundant->flags;
1036 		environment.data	= redundant->data;
1037 	} else {
1038 		single = addr0;
1039 		environment.crc		= &single->crc;
1040 		environment.flags	= NULL;
1041 		environment.data	= single->data;
1042 	}
1043 
1044 	dev_current = 0;
1045 	if (flash_io (O_RDONLY))
1046 		return -1;
1047 
1048 	crc0 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE);
1049 	crc0_ok = (crc0 == *environment.crc);
1050 	if (!HaveRedundEnv) {
1051 		if (!crc0_ok) {
1052 			fprintf (stderr,
1053 				"Warning: Bad CRC, using default environment\n");
1054 			memcpy(environment.data, default_environment, sizeof default_environment);
1055 		}
1056 	} else {
1057 		flag0 = *environment.flags;
1058 
1059 		dev_current = 1;
1060 		addr1 = calloc(1, CUR_ENVSIZE);
1061 		if (addr1 == NULL) {
1062 			fprintf(stderr,
1063 				"Not enough memory for environment (%ld bytes)\n",
1064 				CUR_ENVSIZE);
1065 			return -1;
1066 		}
1067 		redundant = addr1;
1068 
1069 		/*
1070 		 * have to set environment.image for flash_read(), careful -
1071 		 * other pointers in environment still point inside addr0
1072 		 */
1073 		environment.image = addr1;
1074 		if (flash_io (O_RDONLY))
1075 			return -1;
1076 
1077 		/* Check flag scheme compatibility */
1078 		if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1079 		    DEVTYPE(!dev_current) == MTD_NORFLASH) {
1080 			environment.flag_scheme = FLAG_BOOLEAN;
1081 		} else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1082 			   DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1083 			environment.flag_scheme = FLAG_INCREMENTAL;
1084 		} else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1085 			   DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1086 			environment.flag_scheme = FLAG_BOOLEAN;
1087 		} else {
1088 			fprintf (stderr, "Incompatible flash types!\n");
1089 			return -1;
1090 		}
1091 
1092 		crc1 = crc32 (0, (uint8_t *) redundant->data, ENV_SIZE);
1093 		crc1_ok = (crc1 == redundant->crc);
1094 		flag1 = redundant->flags;
1095 
1096 		if (crc0_ok && !crc1_ok) {
1097 			dev_current = 0;
1098 		} else if (!crc0_ok && crc1_ok) {
1099 			dev_current = 1;
1100 		} else if (!crc0_ok && !crc1_ok) {
1101 			fprintf (stderr,
1102 				"Warning: Bad CRC, using default environment\n");
1103 			memcpy (environment.data, default_environment,
1104 				sizeof default_environment);
1105 			dev_current = 0;
1106 		} else {
1107 			switch (environment.flag_scheme) {
1108 			case FLAG_BOOLEAN:
1109 				if (flag0 == active_flag &&
1110 				    flag1 == obsolete_flag) {
1111 					dev_current = 0;
1112 				} else if (flag0 == obsolete_flag &&
1113 					   flag1 == active_flag) {
1114 					dev_current = 1;
1115 				} else if (flag0 == flag1) {
1116 					dev_current = 0;
1117 				} else if (flag0 == 0xFF) {
1118 					dev_current = 0;
1119 				} else if (flag1 == 0xFF) {
1120 					dev_current = 1;
1121 				} else {
1122 					dev_current = 0;
1123 				}
1124 				break;
1125 			case FLAG_INCREMENTAL:
1126 				if (flag0 == 255 && flag1 == 0)
1127 					dev_current = 1;
1128 				else if ((flag1 == 255 && flag0 == 0) ||
1129 					 flag0 >= flag1)
1130 					dev_current = 0;
1131 				else /* flag1 > flag0 */
1132 					dev_current = 1;
1133 				break;
1134 			default:
1135 				fprintf (stderr, "Unknown flag scheme %u \n",
1136 					 environment.flag_scheme);
1137 				return -1;
1138 			}
1139 		}
1140 
1141 		/*
1142 		 * If we are reading, we don't need the flag and the CRC any
1143 		 * more, if we are writing, we will re-calculate CRC and update
1144 		 * flags before writing out
1145 		 */
1146 		if (dev_current) {
1147 			environment.image	= addr1;
1148 			environment.crc		= &redundant->crc;
1149 			environment.flags	= &redundant->flags;
1150 			environment.data	= redundant->data;
1151 			free (addr0);
1152 		} else {
1153 			environment.image	= addr0;
1154 			/* Other pointers are already set */
1155 			free (addr1);
1156 		}
1157 #ifdef DEBUG
1158 		fprintf(stderr, "Selected env in %s\n", DEVNAME(dev_current));
1159 #endif
1160 	}
1161 	return 0;
1162 }
1163 
1164 
1165 static int parse_config ()
1166 {
1167 	struct stat st;
1168 
1169 #if defined(CONFIG_FILE)
1170 	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1171 	if (get_config (CONFIG_FILE)) {
1172 		fprintf (stderr,
1173 			"Cannot parse config file: %s\n", strerror (errno));
1174 		return -1;
1175 	}
1176 #else
1177 	strcpy (DEVNAME (0), DEVICE1_NAME);
1178 	DEVOFFSET (0) = DEVICE1_OFFSET;
1179 	ENVSIZE (0) = ENV1_SIZE;
1180 	/* Default values are: erase-size=env-size, #sectors=1 */
1181 	DEVESIZE (0) = ENVSIZE (0);
1182 	ENVSECTORS (0) = 1;
1183 #ifdef DEVICE1_ESIZE
1184 	DEVESIZE (0) = DEVICE1_ESIZE;
1185 #endif
1186 #ifdef DEVICE1_ENVSECTORS
1187 	ENVSECTORS (0) = DEVICE1_ENVSECTORS;
1188 #endif
1189 
1190 #ifdef HAVE_REDUND
1191 	strcpy (DEVNAME (1), DEVICE2_NAME);
1192 	DEVOFFSET (1) = DEVICE2_OFFSET;
1193 	ENVSIZE (1) = ENV2_SIZE;
1194 	/* Default values are: erase-size=env-size, #sectors=1 */
1195 	DEVESIZE (1) = ENVSIZE (1);
1196 	ENVSECTORS (1) = 1;
1197 #ifdef DEVICE2_ESIZE
1198 	DEVESIZE (1) = DEVICE2_ESIZE;
1199 #endif
1200 #ifdef DEVICE2_ENVSECTORS
1201 	ENVSECTORS (1) = DEVICE2_ENVSECTORS;
1202 #endif
1203 	HaveRedundEnv = 1;
1204 #endif
1205 #endif
1206 	if (stat (DEVNAME (0), &st)) {
1207 		fprintf (stderr,
1208 			"Cannot access MTD device %s: %s\n",
1209 			DEVNAME (0), strerror (errno));
1210 		return -1;
1211 	}
1212 
1213 	if (HaveRedundEnv && stat (DEVNAME (1), &st)) {
1214 		fprintf (stderr,
1215 			"Cannot access MTD device %s: %s\n",
1216 			DEVNAME (1), strerror (errno));
1217 		return -1;
1218 	}
1219 	return 0;
1220 }
1221 
1222 #if defined(CONFIG_FILE)
1223 static int get_config (char *fname)
1224 {
1225 	FILE *fp;
1226 	int i = 0;
1227 	int rc;
1228 	char dump[128];
1229 
1230 	fp = fopen (fname, "r");
1231 	if (fp == NULL)
1232 		return -1;
1233 
1234 	while (i < 2 && fgets (dump, sizeof (dump), fp)) {
1235 		/* Skip incomplete conversions and comment strings */
1236 		if (dump[0] == '#')
1237 			continue;
1238 
1239 		rc = sscanf (dump, "%s %lx %lx %lx %lx",
1240 			     DEVNAME (i),
1241 			     &DEVOFFSET (i),
1242 			     &ENVSIZE (i),
1243 			     &DEVESIZE (i),
1244 			     &ENVSECTORS (i));
1245 
1246 		if (rc < 3)
1247 			continue;
1248 
1249 		if (rc < 4)
1250 			/* Assume the erase size is the same as the env-size */
1251 			DEVESIZE(i) = ENVSIZE(i);
1252 
1253 		if (rc < 5)
1254 			/* Default - 1 sector */
1255 			ENVSECTORS (i) = 1;
1256 
1257 		i++;
1258 	}
1259 	fclose (fp);
1260 
1261 	HaveRedundEnv = i - 1;
1262 	if (!i) {			/* No valid entries found */
1263 		errno = EINVAL;
1264 		return -1;
1265 	} else
1266 		return 0;
1267 }
1268 #endif
1269