2 * NVRAM variable manipulation (common)
4 * Copyright 2004, Broadcom Corporation
5 * Copyright 2009-2010, OpenWrt.org
8 * THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
9 * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
10 * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
11 * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
18 printf("%s(%i) in %s(): %s\n", \
19 __FILE__, __LINE__, __FUNCTION__, msg ? msg : "?")
21 size_t nvram_erase_size = 0;
25 * -- Helper functions --
29 static uint32_t hash(const char *s)
34 hash = 31 * hash + *s++;
39 /* Free all tuples. */
40 static void _nvram_free(nvram_handle_t *h)
43 nvram_tuple_t *t, *next;
46 for (i = 0; i < NVRAM_ARRAYSIZE(h->nvram_hash); i++) {
47 for (t = h->nvram_hash[i]; t; t = next) {
51 h->nvram_hash[i] = NULL;
55 for (t = h->nvram_dead; t; t = next) {
63 /* (Re)allocate NVRAM tuples. */
64 static nvram_tuple_t * _nvram_realloc( nvram_handle_t *h, nvram_tuple_t *t,
65 const char *name, const char *value )
67 if ((strlen(value) + 1) > NVRAM_SPACE)
71 if (!(t = malloc(sizeof(nvram_tuple_t) + strlen(name) + 1)))
75 t->name = (char *) &t[1];
76 strcpy(t->name, name);
82 if (!t->value || strcmp(t->value, value))
84 if(!(t->value = (char *) realloc(t->value, strlen(value)+1)))
87 strcpy(t->value, value);
88 t->value[strlen(value)] = '\0';
94 /* (Re)initialize the hash table. */
95 static int _nvram_rehash(nvram_handle_t *h)
97 nvram_header_t *header = nvram_header(h);
98 char buf[] = "0xXXXXXXXX", *name, *value, *eq;
100 /* (Re)initialize hash table */
103 /* Parse and set "name=value\0 ... \0\0" */
104 name = (char *) &header[1];
106 for (; *name; name = value + strlen(value) + 1) {
107 if (!(eq = strchr(name, '=')))
111 nvram_set(h, name, value);
115 /* Set special SDRAM parameters */
116 if (!nvram_get(h, "sdram_init")) {
117 sprintf(buf, "0x%04X", (uint16_t)(header->crc_ver_init >> 16));
118 nvram_set(h, "sdram_init", buf);
120 if (!nvram_get(h, "sdram_config")) {
121 sprintf(buf, "0x%04X", (uint16_t)(header->config_refresh & 0xffff));
122 nvram_set(h, "sdram_config", buf);
124 if (!nvram_get(h, "sdram_refresh")) {
125 sprintf(buf, "0x%04X",
126 (uint16_t)((header->config_refresh >> 16) & 0xffff));
127 nvram_set(h, "sdram_refresh", buf);
129 if (!nvram_get(h, "sdram_ncdl")) {
130 sprintf(buf, "0x%08X", header->config_ncdl);
131 nvram_set(h, "sdram_ncdl", buf);
139 * -- Public functions --
142 /* Get nvram header. */
143 nvram_header_t * nvram_header(nvram_handle_t *h)
145 return (nvram_header_t *) &h->mmap[h->offset];
148 /* Get the value of an NVRAM variable. */
149 char * nvram_get(nvram_handle_t *h, const char *name)
159 i = hash(name) % NVRAM_ARRAYSIZE(h->nvram_hash);
161 /* Find the associated tuple in the hash table */
162 for (t = h->nvram_hash[i]; t && strcmp(t->name, name); t = t->next);
164 value = t ? t->value : NULL;
169 /* Set the value of an NVRAM variable. */
170 int nvram_set(nvram_handle_t *h, const char *name, const char *value)
173 nvram_tuple_t *t, *u, **prev;
176 i = hash(name) % NVRAM_ARRAYSIZE(h->nvram_hash);
178 /* Find the associated tuple in the hash table */
179 for (prev = &h->nvram_hash[i], t = *prev;
180 t && strcmp(t->name, name); prev = &t->next, t = *prev);
182 /* (Re)allocate tuple */
183 if (!(u = _nvram_realloc(h, t, name, value)))
184 return -12; /* -ENOMEM */
186 /* Value reallocated */
190 /* Move old tuple to the dead table */
193 t->next = h->nvram_dead;
197 /* Add new tuple to the hash table */
198 u->next = h->nvram_hash[i];
199 h->nvram_hash[i] = u;
204 /* Unset the value of an NVRAM variable. */
205 int nvram_unset(nvram_handle_t *h, const char *name)
208 nvram_tuple_t *t, **prev;
214 i = hash(name) % NVRAM_ARRAYSIZE(h->nvram_hash);
216 /* Find the associated tuple in the hash table */
217 for (prev = &h->nvram_hash[i], t = *prev;
218 t && strcmp(t->name, name); prev = &t->next, t = *prev);
220 /* Move it to the dead table */
223 t->next = h->nvram_dead;
230 /* Get all NVRAM variables. */
231 nvram_tuple_t * nvram_getall(nvram_handle_t *h)
234 nvram_tuple_t *t, *l, *x;
238 for (i = 0; i < NVRAM_ARRAYSIZE(h->nvram_hash); i++) {
239 for (t = h->nvram_hash[i]; t; t = t->next) {
240 if( (x = (nvram_tuple_t *) malloc(sizeof(nvram_tuple_t))) != NULL )
257 /* Regenerate NVRAM. */
258 int nvram_commit(nvram_handle_t *h)
260 nvram_header_t *header = nvram_header(h);
261 char *init, *config, *refresh, *ncdl;
268 /* Regenerate header */
269 header->magic = NVRAM_MAGIC;
270 header->crc_ver_init = (NVRAM_VERSION << 8);
271 if (!(init = nvram_get(h, "sdram_init")) ||
272 !(config = nvram_get(h, "sdram_config")) ||
273 !(refresh = nvram_get(h, "sdram_refresh")) ||
274 !(ncdl = nvram_get(h, "sdram_ncdl"))) {
275 header->crc_ver_init |= SDRAM_INIT << 16;
276 header->config_refresh = SDRAM_CONFIG;
277 header->config_refresh |= SDRAM_REFRESH << 16;
278 header->config_ncdl = 0;
280 header->crc_ver_init |= (strtoul(init, NULL, 0) & 0xffff) << 16;
281 header->config_refresh = strtoul(config, NULL, 0) & 0xffff;
282 header->config_refresh |= (strtoul(refresh, NULL, 0) & 0xffff) << 16;
283 header->config_ncdl = strtoul(ncdl, NULL, 0);
286 /* Clear data area */
287 ptr = (char *) header + sizeof(nvram_header_t);
288 memset(ptr, 0xFF, NVRAM_SPACE - sizeof(nvram_header_t));
289 memset(&tmp, 0, sizeof(nvram_header_t));
291 /* Leave space for a double NUL at the end */
292 end = (char *) header + NVRAM_SPACE - 2;
294 /* Write out all tuples */
295 for (i = 0; i < NVRAM_ARRAYSIZE(h->nvram_hash); i++) {
296 for (t = h->nvram_hash[i]; t; t = t->next) {
297 if ((ptr + strlen(t->name) + 1 + strlen(t->value) + 1) > end)
299 ptr += sprintf(ptr, "%s=%s", t->name, t->value) + 1;
303 /* End with a double NULL and pad to 4 bytes */
308 memset(ptr, 0, 4 - ((int)ptr % 4));
313 header->len = NVRAM_ROUNDUP(ptr - (char *) header, 4);
315 /* Little-endian CRC8 over the last 11 bytes of the header */
316 tmp.crc_ver_init = header->crc_ver_init;
317 tmp.config_refresh = header->config_refresh;
318 tmp.config_ncdl = header->config_ncdl;
319 crc = hndcrc8((unsigned char *) &tmp + NVRAM_CRC_START_POSITION,
320 sizeof(nvram_header_t) - NVRAM_CRC_START_POSITION, 0xff);
322 /* Continue CRC8 over data bytes */
323 crc = hndcrc8((unsigned char *) &header[0] + sizeof(nvram_header_t),
324 header->len - sizeof(nvram_header_t), crc);
327 header->crc_ver_init |= crc;
330 msync(h->mmap, h->length, MS_SYNC);
333 /* Reinitialize hash table */
334 return _nvram_rehash(h);
337 /* Open NVRAM and obtain a handle. */
338 nvram_handle_t * nvram_open(const char *file, int rdonly)
344 nvram_header_t *header;
347 /* If erase size or file are undefined then try to define them */
348 if( (nvram_erase_size == 0) || (file == NULL) )
350 /* Finding the mtd will set the appropriate erase size */
351 if( (mtd = nvram_find_mtd()) == NULL || nvram_erase_size == 0 )
358 if( (fd = open(file ? file : mtd, O_RDWR)) > -1 )
360 char *mmap_area = (char *) mmap(
361 NULL, nvram_erase_size, PROT_READ | PROT_WRITE,
362 (( rdonly == NVRAM_RO ) ? MAP_PRIVATE : MAP_SHARED) | MAP_LOCKED, fd, 0);
364 if( mmap_area != MAP_FAILED )
366 for( i = 0; i <= ((nvram_erase_size - NVRAM_SPACE) / sizeof(uint32_t)); i++ )
368 if( ((uint32_t *)mmap_area)[i] == NVRAM_MAGIC )
370 offset = i * sizeof(uint32_t);
380 else if( (h = malloc(sizeof(nvram_handle_t))) != NULL )
382 memset(h, 0, sizeof(nvram_handle_t));
386 h->length = nvram_erase_size;
389 header = nvram_header(h);
391 if( header->magic == NVRAM_MAGIC )
399 munmap(h->mmap, h->length);
410 /* Close NVRAM and free memory. */
411 int nvram_close(nvram_handle_t *h)
414 munmap(h->mmap, h->length);
421 /* Determine NVRAM device node. */
422 char * nvram_find_mtd(void)
431 /* Refuse any operation on the WGT634U */
432 if( (fp = fopen("/proc/diag/model", "r")) )
434 if( fgets(dev, sizeof(dev), fp) && !strncmp(dev, "Netgear WGT634U", 15) )
440 if( supported && (fp = fopen("/proc/mtd", "r")) )
442 while( fgets(dev, sizeof(dev), fp) )
444 if( strstr(dev, "nvram") && sscanf(dev, "mtd%d: %08x", &i, &esz) )
446 nvram_erase_size = esz;
448 sprintf(dev, "/dev/mtdblock/%d", i);
449 if( stat(dev, &s) > -1 && (s.st_mode & S_IFBLK) )
451 if( (path = (char *) malloc(strlen(dev)+1)) != NULL )
453 strncpy(path, dev, strlen(dev)+1);
459 sprintf(dev, "/dev/mtdblock%d", i);
460 if( stat(dev, &s) > -1 && (s.st_mode & S_IFBLK) )
462 if( (path = (char *) malloc(strlen(dev)+1)) != NULL )
464 strncpy(path, dev, strlen(dev)+1);
477 /* Check NVRAM staging file. */
478 char * nvram_find_staging(void)
482 if( (stat(NVRAM_STAGING, &s) > -1) && (s.st_mode & S_IFREG) )
484 return NVRAM_STAGING;
490 /* Copy NVRAM contents to staging file. */
491 int nvram_to_staging(void)
493 int fdmtd, fdstg, stat;
494 char *mtd = nvram_find_mtd();
495 char buf[nvram_erase_size];
499 if( (mtd != NULL) && (nvram_erase_size > 0) )
501 if( (fdmtd = open(mtd, O_RDONLY)) > -1 )
503 if( read(fdmtd, buf, sizeof(buf)) == sizeof(buf) )
505 if((fdstg = open(NVRAM_STAGING, O_WRONLY | O_CREAT, 0600)) > -1)
507 write(fdstg, buf, sizeof(buf));
523 /* Copy staging file to NVRAM device. */
524 int staging_to_nvram(void)
526 int fdmtd, fdstg, stat;
527 char *mtd = nvram_find_mtd();
528 char buf[nvram_erase_size];
532 if( (mtd != NULL) && (nvram_erase_size > 0) )
534 if( (fdstg = open(NVRAM_STAGING, O_RDONLY)) > -1 )
536 if( read(fdstg, buf, sizeof(buf)) == sizeof(buf) )
538 if( (fdmtd = open(mtd, O_WRONLY | O_SYNC)) > -1 )
540 write(fdmtd, buf, sizeof(buf));
550 stat = unlink(NVRAM_STAGING) ? 1 : 0;