xref: /openbmc/u-boot/tools/env/fw_env.c (revision af2a4093)
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 <fcntl.h>
29 #include <linux/stringify.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <stddef.h>
33 #include <string.h>
34 #include <sys/types.h>
35 #include <sys/ioctl.h>
36 #include <sys/stat.h>
37 #include <unistd.h>
38 
39 #ifdef MTD_OLD
40 # include <stdint.h>
41 # include <linux/mtd/mtd.h>
42 #else
43 # define  __user	/* nothing */
44 # include <mtd/mtd-user.h>
45 #endif
46 
47 #include "fw_env.h"
48 
49 #define WHITESPACE(c) ((c == '\t') || (c == ' '))
50 
51 #define min(x, y) ({				\
52 	typeof(x) _min1 = (x);			\
53 	typeof(y) _min2 = (y);			\
54 	(void) (&_min1 == &_min2);		\
55 	_min1 < _min2 ? _min1 : _min2; })
56 
57 struct envdev_s {
58 	char devname[16];		/* Device name */
59 	ulong devoff;			/* Device offset */
60 	ulong env_size;			/* environment size */
61 	ulong erase_size;		/* device erase size */
62 	ulong env_sectors;		/* number of environment sectors */
63 	uint8_t mtd_type;		/* type of the MTD device */
64 };
65 
66 static struct envdev_s envdevices[2] =
67 {
68 	{
69 		.mtd_type = MTD_ABSENT,
70 	}, {
71 		.mtd_type = MTD_ABSENT,
72 	},
73 };
74 static int dev_current;
75 
76 #define DEVNAME(i)    envdevices[(i)].devname
77 #define DEVOFFSET(i)  envdevices[(i)].devoff
78 #define ENVSIZE(i)    envdevices[(i)].env_size
79 #define DEVESIZE(i)   envdevices[(i)].erase_size
80 #define ENVSECTORS(i) envdevices[(i)].env_sectors
81 #define DEVTYPE(i)    envdevices[(i)].mtd_type
82 
83 #define CUR_ENVSIZE ENVSIZE(dev_current)
84 
85 #define ENV_SIZE      getenvsize()
86 
87 struct env_image_single {
88 	uint32_t	crc;	/* CRC32 over data bytes    */
89 	char		data[];
90 };
91 
92 struct env_image_redundant {
93 	uint32_t	crc;	/* CRC32 over data bytes    */
94 	unsigned char	flags;	/* active or obsolete */
95 	char		data[];
96 };
97 
98 enum flag_scheme {
99 	FLAG_NONE,
100 	FLAG_BOOLEAN,
101 	FLAG_INCREMENTAL,
102 };
103 
104 struct environment {
105 	void			*image;
106 	uint32_t		*crc;
107 	unsigned char		*flags;
108 	char			*data;
109 	enum flag_scheme	flag_scheme;
110 };
111 
112 static struct environment environment = {
113 	.flag_scheme = FLAG_NONE,
114 };
115 
116 static int HaveRedundEnv = 0;
117 
118 static unsigned char active_flag = 1;
119 /* obsolete_flag must be 0 to efficiently set it on NOR flash without erasing */
120 static unsigned char obsolete_flag = 0;
121 
122 
123 static char default_environment[] = {
124 #if defined(CONFIG_BOOTARGS)
125 	"bootargs=" CONFIG_BOOTARGS "\0"
126 #endif
127 #if defined(CONFIG_BOOTCOMMAND)
128 	"bootcmd=" CONFIG_BOOTCOMMAND "\0"
129 #endif
130 #if defined(CONFIG_RAMBOOTCOMMAND)
131 	"ramboot=" CONFIG_RAMBOOTCOMMAND "\0"
132 #endif
133 #if defined(CONFIG_NFSBOOTCOMMAND)
134 	"nfsboot=" CONFIG_NFSBOOTCOMMAND "\0"
135 #endif
136 #if defined(CONFIG_BOOTDELAY) && (CONFIG_BOOTDELAY >= 0)
137 	"bootdelay=" __stringify(CONFIG_BOOTDELAY) "\0"
138 #endif
139 #if defined(CONFIG_BAUDRATE) && (CONFIG_BAUDRATE >= 0)
140 	"baudrate=" __stringify(CONFIG_BAUDRATE) "\0"
141 #endif
142 #ifdef	CONFIG_LOADS_ECHO
143 	"loads_echo=" __stringify(CONFIG_LOADS_ECHO) "\0"
144 #endif
145 #ifdef	CONFIG_ETHADDR
146 	"ethaddr=" __stringify(CONFIG_ETHADDR) "\0"
147 #endif
148 #ifdef	CONFIG_ETH1ADDR
149 	"eth1addr=" __stringify(CONFIG_ETH1ADDR) "\0"
150 #endif
151 #ifdef	CONFIG_ETH2ADDR
152 	"eth2addr=" __stringify(CONFIG_ETH2ADDR) "\0"
153 #endif
154 #ifdef	CONFIG_ETH3ADDR
155 	"eth3addr=" __stringify(CONFIG_ETH3ADDR) "\0"
156 #endif
157 #ifdef	CONFIG_ETH4ADDR
158 	"eth4addr=" __stringify(CONFIG_ETH4ADDR) "\0"
159 #endif
160 #ifdef	CONFIG_ETH5ADDR
161 	"eth5addr=" __stringify(CONFIG_ETH5ADDR) "\0"
162 #endif
163 #ifdef	CONFIG_ETHPRIME
164 	"ethprime=" CONFIG_ETHPRIME "\0"
165 #endif
166 #ifdef	CONFIG_IPADDR
167 	"ipaddr=" __stringify(CONFIG_IPADDR) "\0"
168 #endif
169 #ifdef	CONFIG_SERVERIP
170 	"serverip=" __stringify(CONFIG_SERVERIP) "\0"
171 #endif
172 #ifdef	CONFIG_SYS_AUTOLOAD
173 	"autoload=" CONFIG_SYS_AUTOLOAD "\0"
174 #endif
175 #ifdef	CONFIG_ROOTPATH
176 	"rootpath=" CONFIG_ROOTPATH "\0"
177 #endif
178 #ifdef	CONFIG_GATEWAYIP
179 	"gatewayip=" __stringify(CONFIG_GATEWAYIP) "\0"
180 #endif
181 #ifdef	CONFIG_NETMASK
182 	"netmask=" __stringify(CONFIG_NETMASK) "\0"
183 #endif
184 #ifdef	CONFIG_HOSTNAME
185 	"hostname=" __stringify(CONFIG_HOSTNAME) "\0"
186 #endif
187 #ifdef	CONFIG_BOOTFILE
188 	"bootfile=" CONFIG_BOOTFILE "\0"
189 #endif
190 #ifdef	CONFIG_LOADADDR
191 	"loadaddr=" __stringify(CONFIG_LOADADDR) "\0"
192 #endif
193 #ifdef	CONFIG_PREBOOT
194 	"preboot=" CONFIG_PREBOOT "\0"
195 #endif
196 #ifdef	CONFIG_CLOCKS_IN_MHZ
197 	"clocks_in_mhz=" "1" "\0"
198 #endif
199 #if defined(CONFIG_PCI_BOOTDELAY) && (CONFIG_PCI_BOOTDELAY > 0)
200 	"pcidelay=" __stringify(CONFIG_PCI_BOOTDELAY) "\0"
201 #endif
202 #ifdef	CONFIG_ENV_VARS_UBOOT_CONFIG
203 	"arch=" CONFIG_SYS_ARCH "\0"
204 	"cpu=" CONFIG_SYS_CPU "\0"
205 	"board=" CONFIG_SYS_BOARD "\0"
206 #ifdef CONFIG_SYS_VENDOR
207 	"vendor=" CONFIG_SYS_VENDOR "\0"
208 #endif
209 #ifdef CONFIG_SYS_SOC
210 	"soc=" CONFIG_SYS_SOC "\0"
211 #endif
212 #endif
213 #ifdef  CONFIG_EXTRA_ENV_SETTINGS
214 	CONFIG_EXTRA_ENV_SETTINGS
215 #endif
216 	"\0"		/* Termimate struct environment data with 2 NULs */
217 };
218 
219 static int flash_io (int mode);
220 static char *envmatch (char * s1, char * s2);
221 static int parse_config (void);
222 
223 #if defined(CONFIG_FILE)
224 static int get_config (char *);
225 #endif
226 static inline ulong getenvsize (void)
227 {
228 	ulong rc = CUR_ENVSIZE - sizeof(long);
229 
230 	if (HaveRedundEnv)
231 		rc -= sizeof (char);
232 	return rc;
233 }
234 
235 static char *fw_string_blank(char *s, int noblank)
236 {
237 	int i;
238 	int len = strlen(s);
239 
240 	for (i = 0; i < len; i++, s++) {
241 		if ((noblank && !WHITESPACE(*s)) ||
242 			(!noblank && WHITESPACE(*s)))
243 			break;
244 	}
245 	if (i == len)
246 		return NULL;
247 
248 	return s;
249 }
250 
251 /*
252  * Search the environment for a variable.
253  * Return the value, if found, or NULL, if not found.
254  */
255 char *fw_getenv (char *name)
256 {
257 	char *env, *nxt;
258 
259 	for (env = environment.data; *env; env = nxt + 1) {
260 		char *val;
261 
262 		for (nxt = env; *nxt; ++nxt) {
263 			if (nxt >= &environment.data[ENV_SIZE]) {
264 				fprintf (stderr, "## Error: "
265 					"environment not terminated\n");
266 				return NULL;
267 			}
268 		}
269 		val = envmatch (name, env);
270 		if (!val)
271 			continue;
272 		return val;
273 	}
274 	return NULL;
275 }
276 
277 /*
278  * Print the current definition of one, or more, or all
279  * environment variables
280  */
281 int fw_printenv (int argc, char *argv[])
282 {
283 	char *env, *nxt;
284 	int i, n_flag;
285 	int rc = 0;
286 
287 	if (fw_env_open())
288 		return -1;
289 
290 	if (argc == 1) {		/* Print all env variables  */
291 		for (env = environment.data; *env; env = nxt + 1) {
292 			for (nxt = env; *nxt; ++nxt) {
293 				if (nxt >= &environment.data[ENV_SIZE]) {
294 					fprintf (stderr, "## Error: "
295 						"environment not terminated\n");
296 					return -1;
297 				}
298 			}
299 
300 			printf ("%s\n", env);
301 		}
302 		return 0;
303 	}
304 
305 	if (strcmp (argv[1], "-n") == 0) {
306 		n_flag = 1;
307 		++argv;
308 		--argc;
309 		if (argc != 2) {
310 			fprintf (stderr, "## Error: "
311 				"`-n' option requires exactly one argument\n");
312 			return -1;
313 		}
314 	} else {
315 		n_flag = 0;
316 	}
317 
318 	for (i = 1; i < argc; ++i) {	/* print single env variables   */
319 		char *name = argv[i];
320 		char *val = NULL;
321 
322 		for (env = environment.data; *env; env = nxt + 1) {
323 
324 			for (nxt = env; *nxt; ++nxt) {
325 				if (nxt >= &environment.data[ENV_SIZE]) {
326 					fprintf (stderr, "## Error: "
327 						"environment not terminated\n");
328 					return -1;
329 				}
330 			}
331 			val = envmatch (name, env);
332 			if (val) {
333 				if (!n_flag) {
334 					fputs (name, stdout);
335 					putc ('=', stdout);
336 				}
337 				puts (val);
338 				break;
339 			}
340 		}
341 		if (!val) {
342 			fprintf (stderr, "## Error: \"%s\" not defined\n", name);
343 			rc = -1;
344 		}
345 	}
346 
347 	return rc;
348 }
349 
350 int fw_env_close(void)
351 {
352 	/*
353 	 * Update CRC
354 	 */
355 	*environment.crc = crc32(0, (uint8_t *) environment.data, ENV_SIZE);
356 
357 	/* write environment back to flash */
358 	if (flash_io(O_RDWR)) {
359 		fprintf(stderr,
360 			"Error: can't write fw_env to flash\n");
361 			return -1;
362 	}
363 
364 	return 0;
365 }
366 
367 
368 /*
369  * Set/Clear a single variable in the environment.
370  * This is called in sequence to update the environment
371  * in RAM without updating the copy in flash after each set
372  */
373 int fw_env_write(char *name, char *value)
374 {
375 	int len;
376 	char *env, *nxt;
377 	char *oldval = NULL;
378 
379 	/*
380 	 * search if variable with this name already exists
381 	 */
382 	for (nxt = env = environment.data; *env; env = nxt + 1) {
383 		for (nxt = env; *nxt; ++nxt) {
384 			if (nxt >= &environment.data[ENV_SIZE]) {
385 				fprintf(stderr, "## Error: "
386 					"environment not terminated\n");
387 				errno = EINVAL;
388 				return -1;
389 			}
390 		}
391 		if ((oldval = envmatch (name, env)) != NULL)
392 			break;
393 	}
394 
395 	/*
396 	 * Delete any existing definition
397 	 */
398 	if (oldval) {
399 #ifndef CONFIG_ENV_OVERWRITE
400 		/*
401 		 * Ethernet Address and serial# can be set only once
402 		 */
403 		if (
404 		    (strcmp(name, "serial#") == 0) ||
405 		    ((strcmp(name, "ethaddr") == 0)
406 #if defined(CONFIG_OVERWRITE_ETHADDR_ONCE) && defined(CONFIG_ETHADDR)
407 		    && (strcmp(oldval, __stringify(CONFIG_ETHADDR)) != 0)
408 #endif /* CONFIG_OVERWRITE_ETHADDR_ONCE && CONFIG_ETHADDR */
409 		   ) ) {
410 			fprintf (stderr, "Can't overwrite \"%s\"\n", name);
411 			errno = EROFS;
412 			return -1;
413 		}
414 #endif /* CONFIG_ENV_OVERWRITE */
415 
416 		if (*++nxt == '\0') {
417 			*env = '\0';
418 		} else {
419 			for (;;) {
420 				*env = *nxt++;
421 				if ((*env == '\0') && (*nxt == '\0'))
422 					break;
423 				++env;
424 			}
425 		}
426 		*++env = '\0';
427 	}
428 
429 	/* Delete only ? */
430 	if (!value || !strlen(value))
431 		return 0;
432 
433 	/*
434 	 * Append new definition at the end
435 	 */
436 	for (env = environment.data; *env || *(env + 1); ++env);
437 	if (env > environment.data)
438 		++env;
439 	/*
440 	 * Overflow when:
441 	 * "name" + "=" + "val" +"\0\0"  > CUR_ENVSIZE - (env-environment)
442 	 */
443 	len = strlen (name) + 2;
444 	/* add '=' for first arg, ' ' for all others */
445 	len += strlen(value) + 1;
446 
447 	if (len > (&environment.data[ENV_SIZE] - env)) {
448 		fprintf (stderr,
449 			"Error: environment overflow, \"%s\" deleted\n",
450 			name);
451 		return -1;
452 	}
453 
454 	while ((*env = *name++) != '\0')
455 		env++;
456 	*env = '=';
457 	while ((*++env = *value++) != '\0')
458 		;
459 
460 	/* end is marked with double '\0' */
461 	*++env = '\0';
462 
463 	return 0;
464 }
465 
466 /*
467  * Deletes or sets environment variables. Returns -1 and sets errno error codes:
468  * 0	  - OK
469  * EINVAL - need at least 1 argument
470  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
471  *	    modified or deleted
472  *
473  */
474 int fw_setenv(int argc, char *argv[])
475 {
476 	int i, len;
477 	char *name;
478 	char *value = NULL;
479 
480 	if (argc < 2) {
481 		errno = EINVAL;
482 		return -1;
483 	}
484 
485 	if (fw_env_open()) {
486 		fprintf(stderr, "Error: environment not initialized\n");
487 		return -1;
488 	}
489 
490 	name = argv[1];
491 
492 	len = 0;
493 	for (i = 2; i < argc; ++i) {
494 		char *val = argv[i];
495 		size_t val_len = strlen(val);
496 
497 		value = realloc(value, len + val_len + 1);
498 		if (!value) {
499 			fprintf(stderr,
500 				"Cannot malloc %zu bytes: %s\n",
501 				len, strerror(errno));
502 			return -1;
503 		}
504 
505 		memcpy(value + len, val, val_len);
506 		len += val_len;
507 		value[len++] = ' ';
508 	}
509 	value[len - 1] = '\0';
510 
511 	fw_env_write(name, value);
512 
513 	free(value);
514 
515 	return fw_env_close();
516 }
517 
518 /*
519  * Parse  a file  and configure the u-boot variables.
520  * The script file has a very simple format, as follows:
521  *
522  * Each line has a couple with name, value:
523  * <white spaces>variable_name<white spaces>variable_value
524  *
525  * Both variable_name and variable_value are interpreted as strings.
526  * Any character after <white spaces> and before ending \r\n is interpreted
527  * as variable's value (no comment allowed on these lines !)
528  *
529  * Comments are allowed if the first character in the line is #
530  *
531  * Returns -1 and sets errno error codes:
532  * 0	  - OK
533  * -1     - Error
534  */
535 int fw_parse_script(char *fname)
536 {
537 	FILE *fp;
538 	char dump[1024];	/* Maximum line length in the file */
539 	char *name;
540 	char *val;
541 	int lineno = 0;
542 	int len;
543 	int ret = 0;
544 
545 	if (fw_env_open()) {
546 		fprintf(stderr, "Error: environment not initialized\n");
547 		return -1;
548 	}
549 
550 	if (strcmp(fname, "-") == 0)
551 		fp = stdin;
552 	else {
553 		fp = fopen(fname, "r");
554 		if (fp == NULL) {
555 			fprintf(stderr, "I cannot open %s for reading\n",
556 				 fname);
557 			return -1;
558 		}
559 	}
560 
561 	while (fgets(dump, sizeof(dump), fp)) {
562 		lineno++;
563 		len = strlen(dump);
564 
565 		/*
566 		 * Read a whole line from the file. If the line is too long
567 		 * or is not terminated, reports an error and exit.
568 		 */
569 		if (dump[len - 1] != '\n') {
570 			fprintf(stderr,
571 			"Line %d not corrected terminated or too long\n",
572 				lineno);
573 			ret = -1;
574 			break;
575 		}
576 
577 		/* Drop ending line feed / carriage return */
578 		while (len > 0 && (dump[len - 1] == '\n' ||
579 				dump[len - 1] == '\r')) {
580 			dump[len - 1] = '\0';
581 			len--;
582 		}
583 
584 		/* Skip comment or empty lines */
585 		if ((len == 0) || dump[0] == '#')
586 			continue;
587 
588 		/*
589 		 * Search for variable's name,
590 		 * remove leading whitespaces
591 		 */
592 		name = fw_string_blank(dump, 1);
593 		if (!name)
594 			continue;
595 
596 		/* The first white space is the end of variable name */
597 		val = fw_string_blank(name, 0);
598 		len = strlen(name);
599 		if (val) {
600 			*val++ = '\0';
601 			if ((val - name) < len)
602 				val = fw_string_blank(val, 1);
603 			else
604 				val = NULL;
605 		}
606 
607 #ifdef DEBUG
608 		fprintf(stderr, "Setting %s : %s\n",
609 			name, val ? val : " removed");
610 #endif
611 
612 		/*
613 		 * If there is an error setting a variable,
614 		 * try to save the environment and returns an error
615 		 */
616 		if (fw_env_write(name, val)) {
617 			fprintf(stderr,
618 			"fw_env_write returns with error : %s\n",
619 				strerror(errno));
620 			ret = -1;
621 			break;
622 		}
623 
624 	}
625 
626 	/* Close file if not stdin */
627 	if (strcmp(fname, "-") != 0)
628 		fclose(fp);
629 
630 	ret |= fw_env_close();
631 
632 	return ret;
633 
634 }
635 
636 /*
637  * Test for bad block on NAND, just returns 0 on NOR, on NAND:
638  * 0	- block is good
639  * > 0	- block is bad
640  * < 0	- failed to test
641  */
642 static int flash_bad_block (int fd, uint8_t mtd_type, loff_t *blockstart)
643 {
644 	if (mtd_type == MTD_NANDFLASH) {
645 		int badblock = ioctl (fd, MEMGETBADBLOCK, blockstart);
646 
647 		if (badblock < 0) {
648 			perror ("Cannot read bad block mark");
649 			return badblock;
650 		}
651 
652 		if (badblock) {
653 #ifdef DEBUG
654 			fprintf (stderr, "Bad block at 0x%llx, "
655 				 "skipping\n", *blockstart);
656 #endif
657 			return badblock;
658 		}
659 	}
660 
661 	return 0;
662 }
663 
664 /*
665  * Read data from flash at an offset into a provided buffer. On NAND it skips
666  * bad blocks but makes sure it stays within ENVSECTORS (dev) starting from
667  * the DEVOFFSET (dev) block. On NOR the loop is only run once.
668  */
669 static int flash_read_buf (int dev, int fd, void *buf, size_t count,
670 			   off_t offset, uint8_t mtd_type)
671 {
672 	size_t blocklen;	/* erase / write length - one block on NAND,
673 				   0 on NOR */
674 	size_t processed = 0;	/* progress counter */
675 	size_t readlen = count;	/* current read length */
676 	off_t top_of_range;	/* end of the last block we may use */
677 	off_t block_seek;	/* offset inside the current block to the start
678 				   of the data */
679 	loff_t blockstart;	/* running start of the current block -
680 				   MEMGETBADBLOCK needs 64 bits */
681 	int rc;
682 
683 	blockstart = (offset / DEVESIZE (dev)) * DEVESIZE (dev);
684 
685 	/* Offset inside a block */
686 	block_seek = offset - blockstart;
687 
688 	if (mtd_type == MTD_NANDFLASH) {
689 		/*
690 		 * NAND: calculate which blocks we are reading. We have
691 		 * to read one block at a time to skip bad blocks.
692 		 */
693 		blocklen = DEVESIZE (dev);
694 
695 		/*
696 		 * To calculate the top of the range, we have to use the
697 		 * global DEVOFFSET (dev), which can be different from offset
698 		 */
699 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
700 				ENVSECTORS (dev)) * blocklen;
701 
702 		/* Limit to one block for the first read */
703 		if (readlen > blocklen - block_seek)
704 			readlen = blocklen - block_seek;
705 	} else {
706 		blocklen = 0;
707 		top_of_range = offset + count;
708 	}
709 
710 	/* This only runs once on NOR flash */
711 	while (processed < count) {
712 		rc = flash_bad_block (fd, mtd_type, &blockstart);
713 		if (rc < 0)		/* block test failed */
714 			return -1;
715 
716 		if (blockstart + block_seek + readlen > top_of_range) {
717 			/* End of range is reached */
718 			fprintf (stderr,
719 				 "Too few good blocks within range\n");
720 			return -1;
721 		}
722 
723 		if (rc) {		/* block is bad */
724 			blockstart += blocklen;
725 			continue;
726 		}
727 
728 		/*
729 		 * If a block is bad, we retry in the next block at the same
730 		 * offset - see common/env_nand.c::writeenv()
731 		 */
732 		lseek (fd, blockstart + block_seek, SEEK_SET);
733 
734 		rc = read (fd, buf + processed, readlen);
735 		if (rc != readlen) {
736 			fprintf (stderr, "Read error on %s: %s\n",
737 				 DEVNAME (dev), strerror (errno));
738 			return -1;
739 		}
740 #ifdef DEBUG
741 		fprintf (stderr, "Read 0x%x bytes at 0x%llx\n",
742 			 rc, blockstart + block_seek);
743 #endif
744 		processed += readlen;
745 		readlen = min (blocklen, count - processed);
746 		block_seek = 0;
747 		blockstart += blocklen;
748 	}
749 
750 	return processed;
751 }
752 
753 /*
754  * Write count bytes at offset, but stay within ENVSECTORS (dev) sectors of
755  * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
756  * erase and write the whole data at once.
757  */
758 static int flash_write_buf (int dev, int fd, void *buf, size_t count,
759 			    off_t offset, uint8_t mtd_type)
760 {
761 	void *data;
762 	struct erase_info_user erase;
763 	size_t blocklen;	/* length of NAND block / NOR erase sector */
764 	size_t erase_len;	/* whole area that can be erased - may include
765 				   bad blocks */
766 	size_t erasesize;	/* erase / write length - one block on NAND,
767 				   whole area on NOR */
768 	size_t processed = 0;	/* progress counter */
769 	size_t write_total;	/* total size to actually write - excluding
770 				   bad blocks */
771 	off_t erase_offset;	/* offset to the first erase block (aligned)
772 				   below offset */
773 	off_t block_seek;	/* offset inside the erase block to the start
774 				   of the data */
775 	off_t top_of_range;	/* end of the last block we may use */
776 	loff_t blockstart;	/* running start of the current block -
777 				   MEMGETBADBLOCK needs 64 bits */
778 	int rc;
779 
780 	blocklen = DEVESIZE (dev);
781 
782 	top_of_range = ((DEVOFFSET(dev) / blocklen) +
783 					ENVSECTORS (dev)) * blocklen;
784 
785 	erase_offset = (offset / blocklen) * blocklen;
786 
787 	/* Maximum area we may use */
788 	erase_len = top_of_range - erase_offset;
789 
790 	blockstart = erase_offset;
791 	/* Offset inside a block */
792 	block_seek = offset - erase_offset;
793 
794 	/*
795 	 * Data size we actually have to write: from the start of the block
796 	 * to the start of the data, then count bytes of data, and to the
797 	 * end of the block
798 	 */
799 	write_total = ((block_seek + count + blocklen - 1) /
800 						blocklen) * blocklen;
801 
802 	/*
803 	 * Support data anywhere within erase sectors: read out the complete
804 	 * area to be erased, replace the environment image, write the whole
805 	 * block back again.
806 	 */
807 	if (write_total > count) {
808 		data = malloc (erase_len);
809 		if (!data) {
810 			fprintf (stderr,
811 				 "Cannot malloc %zu bytes: %s\n",
812 				 erase_len, strerror (errno));
813 			return -1;
814 		}
815 
816 		rc = flash_read_buf (dev, fd, data, write_total, erase_offset,
817 				     mtd_type);
818 		if (write_total != rc)
819 			return -1;
820 
821 		/* Overwrite the old environment */
822 		memcpy (data + block_seek, buf, count);
823 	} else {
824 		/*
825 		 * We get here, iff offset is block-aligned and count is a
826 		 * multiple of blocklen - see write_total calculation above
827 		 */
828 		data = buf;
829 	}
830 
831 	if (mtd_type == MTD_NANDFLASH) {
832 		/*
833 		 * NAND: calculate which blocks we are writing. We have
834 		 * to write one block at a time to skip bad blocks.
835 		 */
836 		erasesize = blocklen;
837 	} else {
838 		erasesize = erase_len;
839 	}
840 
841 	erase.length = erasesize;
842 
843 	/* This only runs once on NOR flash and SPI-dataflash */
844 	while (processed < write_total) {
845 		rc = flash_bad_block (fd, mtd_type, &blockstart);
846 		if (rc < 0)		/* block test failed */
847 			return rc;
848 
849 		if (blockstart + erasesize > top_of_range) {
850 			fprintf (stderr, "End of range reached, aborting\n");
851 			return -1;
852 		}
853 
854 		if (rc) {		/* block is bad */
855 			blockstart += blocklen;
856 			continue;
857 		}
858 
859 		erase.start = blockstart;
860 		ioctl (fd, MEMUNLOCK, &erase);
861 
862 		/* Dataflash does not need an explicit erase cycle */
863 		if (mtd_type != MTD_DATAFLASH)
864 			if (ioctl (fd, MEMERASE, &erase) != 0) {
865 				fprintf (stderr, "MTD erase error on %s: %s\n",
866 					 DEVNAME (dev),
867 					 strerror (errno));
868 				return -1;
869 			}
870 
871 		if (lseek (fd, blockstart, SEEK_SET) == -1) {
872 			fprintf (stderr,
873 				 "Seek error on %s: %s\n",
874 				 DEVNAME (dev), strerror (errno));
875 			return -1;
876 		}
877 
878 #ifdef DEBUG
879 		printf ("Write 0x%x bytes at 0x%llx\n", erasesize, blockstart);
880 #endif
881 		if (write (fd, data + processed, erasesize) != erasesize) {
882 			fprintf (stderr, "Write error on %s: %s\n",
883 				 DEVNAME (dev), strerror (errno));
884 			return -1;
885 		}
886 
887 		ioctl (fd, MEMLOCK, &erase);
888 
889 		processed  += blocklen;
890 		block_seek = 0;
891 		blockstart += blocklen;
892 	}
893 
894 	if (write_total > count)
895 		free (data);
896 
897 	return processed;
898 }
899 
900 /*
901  * Set obsolete flag at offset - NOR flash only
902  */
903 static int flash_flag_obsolete (int dev, int fd, off_t offset)
904 {
905 	int rc;
906 	struct erase_info_user erase;
907 
908 	erase.start  = DEVOFFSET (dev);
909 	erase.length = DEVESIZE (dev);
910 	/* This relies on the fact, that obsolete_flag == 0 */
911 	rc = lseek (fd, offset, SEEK_SET);
912 	if (rc < 0) {
913 		fprintf (stderr, "Cannot seek to set the flag on %s \n",
914 			 DEVNAME (dev));
915 		return rc;
916 	}
917 	ioctl (fd, MEMUNLOCK, &erase);
918 	rc = write (fd, &obsolete_flag, sizeof (obsolete_flag));
919 	ioctl (fd, MEMLOCK, &erase);
920 	if (rc < 0)
921 		perror ("Could not set obsolete flag");
922 
923 	return rc;
924 }
925 
926 static int flash_write (int fd_current, int fd_target, int dev_target)
927 {
928 	int rc;
929 
930 	switch (environment.flag_scheme) {
931 	case FLAG_NONE:
932 		break;
933 	case FLAG_INCREMENTAL:
934 		(*environment.flags)++;
935 		break;
936 	case FLAG_BOOLEAN:
937 		*environment.flags = active_flag;
938 		break;
939 	default:
940 		fprintf (stderr, "Unimplemented flash scheme %u \n",
941 			 environment.flag_scheme);
942 		return -1;
943 	}
944 
945 #ifdef DEBUG
946 	printf ("Writing new environment at 0x%lx on %s\n",
947 		DEVOFFSET (dev_target), DEVNAME (dev_target));
948 #endif
949 	rc = flash_write_buf(dev_target, fd_target, environment.image,
950 			      CUR_ENVSIZE, DEVOFFSET(dev_target),
951 			      DEVTYPE(dev_target));
952 	if (rc < 0)
953 		return rc;
954 
955 	if (environment.flag_scheme == FLAG_BOOLEAN) {
956 		/* Have to set obsolete flag */
957 		off_t offset = DEVOFFSET (dev_current) +
958 			offsetof (struct env_image_redundant, flags);
959 #ifdef DEBUG
960 		printf ("Setting obsolete flag in environment at 0x%lx on %s\n",
961 			DEVOFFSET (dev_current), DEVNAME (dev_current));
962 #endif
963 		flash_flag_obsolete (dev_current, fd_current, offset);
964 	}
965 
966 	return 0;
967 }
968 
969 static int flash_read (int fd)
970 {
971 	struct mtd_info_user mtdinfo;
972 	int rc;
973 
974 	rc = ioctl (fd, MEMGETINFO, &mtdinfo);
975 	if (rc < 0) {
976 		perror ("Cannot get MTD information");
977 		return -1;
978 	}
979 
980 	if (mtdinfo.type != MTD_NORFLASH &&
981 	    mtdinfo.type != MTD_NANDFLASH &&
982 	    mtdinfo.type != MTD_DATAFLASH) {
983 		fprintf (stderr, "Unsupported flash type %u\n", mtdinfo.type);
984 		return -1;
985 	}
986 
987 	DEVTYPE(dev_current) = mtdinfo.type;
988 
989 	rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
990 			     DEVOFFSET (dev_current), mtdinfo.type);
991 
992 	return (rc != CUR_ENVSIZE) ? -1 : 0;
993 }
994 
995 static int flash_io (int mode)
996 {
997 	int fd_current, fd_target, rc, dev_target;
998 
999 	/* dev_current: fd_current, erase_current */
1000 	fd_current = open (DEVNAME (dev_current), mode);
1001 	if (fd_current < 0) {
1002 		fprintf (stderr,
1003 			 "Can't open %s: %s\n",
1004 			 DEVNAME (dev_current), strerror (errno));
1005 		return -1;
1006 	}
1007 
1008 	if (mode == O_RDWR) {
1009 		if (HaveRedundEnv) {
1010 			/* switch to next partition for writing */
1011 			dev_target = !dev_current;
1012 			/* dev_target: fd_target, erase_target */
1013 			fd_target = open (DEVNAME (dev_target), mode);
1014 			if (fd_target < 0) {
1015 				fprintf (stderr,
1016 					 "Can't open %s: %s\n",
1017 					 DEVNAME (dev_target),
1018 					 strerror (errno));
1019 				rc = -1;
1020 				goto exit;
1021 			}
1022 		} else {
1023 			dev_target = dev_current;
1024 			fd_target = fd_current;
1025 		}
1026 
1027 		rc = flash_write (fd_current, fd_target, dev_target);
1028 
1029 		if (HaveRedundEnv) {
1030 			if (close (fd_target)) {
1031 				fprintf (stderr,
1032 					"I/O error on %s: %s\n",
1033 					DEVNAME (dev_target),
1034 					strerror (errno));
1035 				rc = -1;
1036 			}
1037 		}
1038 	} else {
1039 		rc = flash_read (fd_current);
1040 	}
1041 
1042 exit:
1043 	if (close (fd_current)) {
1044 		fprintf (stderr,
1045 			 "I/O error on %s: %s\n",
1046 			 DEVNAME (dev_current), strerror (errno));
1047 		return -1;
1048 	}
1049 
1050 	return rc;
1051 }
1052 
1053 /*
1054  * s1 is either a simple 'name', or a 'name=value' pair.
1055  * s2 is a 'name=value' pair.
1056  * If the names match, return the value of s2, else NULL.
1057  */
1058 
1059 static char *envmatch (char * s1, char * s2)
1060 {
1061 	if (s1 == NULL || s2 == NULL)
1062 		return NULL;
1063 
1064 	while (*s1 == *s2++)
1065 		if (*s1++ == '=')
1066 			return s2;
1067 	if (*s1 == '\0' && *(s2 - 1) == '=')
1068 		return s2;
1069 	return NULL;
1070 }
1071 
1072 /*
1073  * Prevent confusion if running from erased flash memory
1074  */
1075 int fw_env_open(void)
1076 {
1077 	int crc0, crc0_ok;
1078 	unsigned char flag0;
1079 	void *addr0;
1080 
1081 	int crc1, crc1_ok;
1082 	unsigned char flag1;
1083 	void *addr1;
1084 
1085 	struct env_image_single *single;
1086 	struct env_image_redundant *redundant;
1087 
1088 	if (parse_config ())		/* should fill envdevices */
1089 		return -1;
1090 
1091 	addr0 = calloc(1, CUR_ENVSIZE);
1092 	if (addr0 == NULL) {
1093 		fprintf(stderr,
1094 			"Not enough memory for environment (%ld bytes)\n",
1095 			CUR_ENVSIZE);
1096 		return -1;
1097 	}
1098 
1099 	/* read environment from FLASH to local buffer */
1100 	environment.image = addr0;
1101 
1102 	if (HaveRedundEnv) {
1103 		redundant = addr0;
1104 		environment.crc		= &redundant->crc;
1105 		environment.flags	= &redundant->flags;
1106 		environment.data	= redundant->data;
1107 	} else {
1108 		single = addr0;
1109 		environment.crc		= &single->crc;
1110 		environment.flags	= NULL;
1111 		environment.data	= single->data;
1112 	}
1113 
1114 	dev_current = 0;
1115 	if (flash_io (O_RDONLY))
1116 		return -1;
1117 
1118 	crc0 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE);
1119 	crc0_ok = (crc0 == *environment.crc);
1120 	if (!HaveRedundEnv) {
1121 		if (!crc0_ok) {
1122 			fprintf (stderr,
1123 				"Warning: Bad CRC, using default environment\n");
1124 			memcpy(environment.data, default_environment, sizeof default_environment);
1125 		}
1126 	} else {
1127 		flag0 = *environment.flags;
1128 
1129 		dev_current = 1;
1130 		addr1 = calloc(1, CUR_ENVSIZE);
1131 		if (addr1 == NULL) {
1132 			fprintf(stderr,
1133 				"Not enough memory for environment (%ld bytes)\n",
1134 				CUR_ENVSIZE);
1135 			return -1;
1136 		}
1137 		redundant = addr1;
1138 
1139 		/*
1140 		 * have to set environment.image for flash_read(), careful -
1141 		 * other pointers in environment still point inside addr0
1142 		 */
1143 		environment.image = addr1;
1144 		if (flash_io (O_RDONLY))
1145 			return -1;
1146 
1147 		/* Check flag scheme compatibility */
1148 		if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1149 		    DEVTYPE(!dev_current) == MTD_NORFLASH) {
1150 			environment.flag_scheme = FLAG_BOOLEAN;
1151 		} else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1152 			   DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1153 			environment.flag_scheme = FLAG_INCREMENTAL;
1154 		} else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1155 			   DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1156 			environment.flag_scheme = FLAG_BOOLEAN;
1157 		} else {
1158 			fprintf (stderr, "Incompatible flash types!\n");
1159 			return -1;
1160 		}
1161 
1162 		crc1 = crc32 (0, (uint8_t *) redundant->data, ENV_SIZE);
1163 		crc1_ok = (crc1 == redundant->crc);
1164 		flag1 = redundant->flags;
1165 
1166 		if (crc0_ok && !crc1_ok) {
1167 			dev_current = 0;
1168 		} else if (!crc0_ok && crc1_ok) {
1169 			dev_current = 1;
1170 		} else if (!crc0_ok && !crc1_ok) {
1171 			fprintf (stderr,
1172 				"Warning: Bad CRC, using default environment\n");
1173 			memcpy (environment.data, default_environment,
1174 				sizeof default_environment);
1175 			dev_current = 0;
1176 		} else {
1177 			switch (environment.flag_scheme) {
1178 			case FLAG_BOOLEAN:
1179 				if (flag0 == active_flag &&
1180 				    flag1 == obsolete_flag) {
1181 					dev_current = 0;
1182 				} else if (flag0 == obsolete_flag &&
1183 					   flag1 == active_flag) {
1184 					dev_current = 1;
1185 				} else if (flag0 == flag1) {
1186 					dev_current = 0;
1187 				} else if (flag0 == 0xFF) {
1188 					dev_current = 0;
1189 				} else if (flag1 == 0xFF) {
1190 					dev_current = 1;
1191 				} else {
1192 					dev_current = 0;
1193 				}
1194 				break;
1195 			case FLAG_INCREMENTAL:
1196 				if (flag0 == 255 && flag1 == 0)
1197 					dev_current = 1;
1198 				else if ((flag1 == 255 && flag0 == 0) ||
1199 					 flag0 >= flag1)
1200 					dev_current = 0;
1201 				else /* flag1 > flag0 */
1202 					dev_current = 1;
1203 				break;
1204 			default:
1205 				fprintf (stderr, "Unknown flag scheme %u \n",
1206 					 environment.flag_scheme);
1207 				return -1;
1208 			}
1209 		}
1210 
1211 		/*
1212 		 * If we are reading, we don't need the flag and the CRC any
1213 		 * more, if we are writing, we will re-calculate CRC and update
1214 		 * flags before writing out
1215 		 */
1216 		if (dev_current) {
1217 			environment.image	= addr1;
1218 			environment.crc		= &redundant->crc;
1219 			environment.flags	= &redundant->flags;
1220 			environment.data	= redundant->data;
1221 			free (addr0);
1222 		} else {
1223 			environment.image	= addr0;
1224 			/* Other pointers are already set */
1225 			free (addr1);
1226 		}
1227 	}
1228 	return 0;
1229 }
1230 
1231 
1232 static int parse_config ()
1233 {
1234 	struct stat st;
1235 
1236 #if defined(CONFIG_FILE)
1237 	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1238 	if (get_config (CONFIG_FILE)) {
1239 		fprintf (stderr,
1240 			"Cannot parse config file: %s\n", strerror (errno));
1241 		return -1;
1242 	}
1243 #else
1244 	strcpy (DEVNAME (0), DEVICE1_NAME);
1245 	DEVOFFSET (0) = DEVICE1_OFFSET;
1246 	ENVSIZE (0) = ENV1_SIZE;
1247 	/* Default values are: erase-size=env-size, #sectors=1 */
1248 	DEVESIZE (0) = ENVSIZE (0);
1249 	ENVSECTORS (0) = 1;
1250 #ifdef DEVICE1_ESIZE
1251 	DEVESIZE (0) = DEVICE1_ESIZE;
1252 #endif
1253 #ifdef DEVICE1_ENVSECTORS
1254 	ENVSECTORS (0) = DEVICE1_ENVSECTORS;
1255 #endif
1256 
1257 #ifdef HAVE_REDUND
1258 	strcpy (DEVNAME (1), DEVICE2_NAME);
1259 	DEVOFFSET (1) = DEVICE2_OFFSET;
1260 	ENVSIZE (1) = ENV2_SIZE;
1261 	/* Default values are: erase-size=env-size, #sectors=1 */
1262 	DEVESIZE (1) = ENVSIZE (1);
1263 	ENVSECTORS (1) = 1;
1264 #ifdef DEVICE2_ESIZE
1265 	DEVESIZE (1) = DEVICE2_ESIZE;
1266 #endif
1267 #ifdef DEVICE2_ENVSECTORS
1268 	ENVSECTORS (1) = DEVICE2_ENVSECTORS;
1269 #endif
1270 	HaveRedundEnv = 1;
1271 #endif
1272 #endif
1273 	if (stat (DEVNAME (0), &st)) {
1274 		fprintf (stderr,
1275 			"Cannot access MTD device %s: %s\n",
1276 			DEVNAME (0), strerror (errno));
1277 		return -1;
1278 	}
1279 
1280 	if (HaveRedundEnv && stat (DEVNAME (1), &st)) {
1281 		fprintf (stderr,
1282 			"Cannot access MTD device %s: %s\n",
1283 			DEVNAME (1), strerror (errno));
1284 		return -1;
1285 	}
1286 	return 0;
1287 }
1288 
1289 #if defined(CONFIG_FILE)
1290 static int get_config (char *fname)
1291 {
1292 	FILE *fp;
1293 	int i = 0;
1294 	int rc;
1295 	char dump[128];
1296 
1297 	fp = fopen (fname, "r");
1298 	if (fp == NULL)
1299 		return -1;
1300 
1301 	while (i < 2 && fgets (dump, sizeof (dump), fp)) {
1302 		/* Skip incomplete conversions and comment strings */
1303 		if (dump[0] == '#')
1304 			continue;
1305 
1306 		rc = sscanf (dump, "%s %lx %lx %lx %lx",
1307 			     DEVNAME (i),
1308 			     &DEVOFFSET (i),
1309 			     &ENVSIZE (i),
1310 			     &DEVESIZE (i),
1311 			     &ENVSECTORS (i));
1312 
1313 		if (rc < 3)
1314 			continue;
1315 
1316 		if (rc < 4)
1317 			/* Assume the erase size is the same as the env-size */
1318 			DEVESIZE(i) = ENVSIZE(i);
1319 
1320 		if (rc < 5)
1321 			/* Default - 1 sector */
1322 			ENVSECTORS (i) = 1;
1323 
1324 		i++;
1325 	}
1326 	fclose (fp);
1327 
1328 	HaveRedundEnv = i - 1;
1329 	if (!i) {			/* No valid entries found */
1330 		errno = EINVAL;
1331 		return -1;
1332 	} else
1333 		return 0;
1334 }
1335 #endif
1336