eeprom.c 11 KB

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  1. // SPDX-License-Identifier: GPL-2.0+
  2. /*
  3. * (C) Copyright 2000, 2001
  4. * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  5. */
  6. /*
  7. * Support for read and write access to EEPROM like memory devices. This
  8. * includes regular EEPROM as well as FRAM (ferroelectic nonvolaile RAM).
  9. * FRAM devices read and write data at bus speed. In particular, there is no
  10. * write delay. Also, there is no limit imposed on the number of bytes that can
  11. * be transferred with a single read or write.
  12. *
  13. * Use the following configuration options to ensure no unneeded performance
  14. * degradation (typical for EEPROM) is incured for FRAM memory:
  15. *
  16. * #define CONFIG_SYS_I2C_FRAM
  17. * Set CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS to 0
  18. *
  19. */
  20. #include <common.h>
  21. #include <config.h>
  22. #include <command.h>
  23. #include <eeprom.h>
  24. #include <i2c.h>
  25. #include <eeprom_layout.h>
  26. #include <linux/delay.h>
  27. #ifndef CONFIG_SYS_I2C_SPEED
  28. #define CONFIG_SYS_I2C_SPEED 50000
  29. #endif
  30. #ifndef I2C_RXTX_LEN
  31. #define I2C_RXTX_LEN 128
  32. #endif
  33. #define EEPROM_PAGE_SIZE (1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)
  34. #define EEPROM_PAGE_OFFSET(x) ((x) & (EEPROM_PAGE_SIZE - 1))
  35. #if CONFIG_IS_ENABLED(DM_I2C)
  36. static int eeprom_i2c_bus;
  37. #endif
  38. __weak int eeprom_write_enable(unsigned dev_addr, int state)
  39. {
  40. return 0;
  41. }
  42. void eeprom_init(int bus)
  43. {
  44. /* I2C EEPROM */
  45. #if CONFIG_IS_ENABLED(DM_I2C)
  46. eeprom_i2c_bus = bus;
  47. #elif defined(CONFIG_SYS_I2C_LEGACY)
  48. if (bus >= 0)
  49. i2c_set_bus_num(bus);
  50. i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
  51. #endif
  52. }
  53. /*
  54. * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
  55. * 0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
  56. *
  57. * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
  58. * 0x00000nxx for EEPROM address selectors and page number at n.
  59. */
  60. static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
  61. {
  62. unsigned blk_off;
  63. int alen;
  64. blk_off = offset & 0xff; /* block offset */
  65. #if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1
  66. addr[0] = offset >> 8; /* block number */
  67. addr[1] = blk_off; /* block offset */
  68. alen = 2;
  69. #else
  70. addr[0] = offset >> 16; /* block number */
  71. addr[1] = offset >> 8; /* upper address octet */
  72. addr[2] = blk_off; /* lower address octet */
  73. alen = 3;
  74. #endif /* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
  75. addr[0] |= dev_addr; /* insert device address */
  76. return alen;
  77. }
  78. static int eeprom_len(unsigned offset, unsigned end)
  79. {
  80. unsigned len = end - offset;
  81. /*
  82. * For a FRAM device there is no limit on the number of the
  83. * bytes that can be accessed with the single read or write
  84. * operation.
  85. */
  86. #if !defined(CONFIG_SYS_I2C_FRAM)
  87. unsigned blk_off = offset & 0xff;
  88. unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
  89. if (maxlen > I2C_RXTX_LEN)
  90. maxlen = I2C_RXTX_LEN;
  91. if (len > maxlen)
  92. len = maxlen;
  93. #endif
  94. return len;
  95. }
  96. static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
  97. uchar *buffer, unsigned len, bool read)
  98. {
  99. int ret = 0;
  100. #if CONFIG_IS_ENABLED(DM_I2C)
  101. struct udevice *dev;
  102. ret = i2c_get_chip_for_busnum(eeprom_i2c_bus, addr[0],
  103. alen - 1, &dev);
  104. if (ret) {
  105. printf("%s: Cannot find udev for a bus %d\n", __func__,
  106. eeprom_i2c_bus);
  107. return CMD_RET_FAILURE;
  108. }
  109. if (read)
  110. ret = dm_i2c_read(dev, offset, buffer, len);
  111. else
  112. ret = dm_i2c_write(dev, offset, buffer, len);
  113. #else /* Non DM I2C support - will be removed */
  114. if (read)
  115. ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
  116. else
  117. ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
  118. #endif /* CONFIG_DM_I2C */
  119. if (ret)
  120. ret = CMD_RET_FAILURE;
  121. return ret;
  122. }
  123. static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
  124. unsigned cnt, bool read)
  125. {
  126. unsigned end = offset + cnt;
  127. unsigned alen, len;
  128. int rcode = 0;
  129. uchar addr[3];
  130. #if defined(CONFIG_SYS_I2C_EEPROM_BUS)
  131. eeprom_init(CONFIG_SYS_I2C_EEPROM_BUS);
  132. #endif
  133. while (offset < end) {
  134. alen = eeprom_addr(dev_addr, offset, addr);
  135. len = eeprom_len(offset, end);
  136. rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
  137. buffer += len;
  138. offset += len;
  139. #if CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS > 0
  140. if (!read)
  141. udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
  142. }
  143. #endif
  144. return rcode;
  145. }
  146. int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
  147. {
  148. /*
  149. * Read data until done or would cross a page boundary.
  150. * We must write the address again when changing pages
  151. * because the next page may be in a different device.
  152. */
  153. return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
  154. }
  155. int eeprom_write(unsigned dev_addr, unsigned offset,
  156. uchar *buffer, unsigned cnt)
  157. {
  158. int ret;
  159. eeprom_write_enable(dev_addr, 1);
  160. /*
  161. * Write data until done or would cross a write page boundary.
  162. * We must write the address again when changing pages
  163. * because the address counter only increments within a page.
  164. */
  165. ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
  166. eeprom_write_enable(dev_addr, 0);
  167. return ret;
  168. }
  169. static long parse_numeric_param(char *str)
  170. {
  171. char *endptr;
  172. long value = simple_strtol(str, &endptr, 16);
  173. return (*endptr != '\0') ? -1 : value;
  174. }
  175. /**
  176. * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
  177. *
  178. * @i2c_bus: address to store the i2c bus
  179. * @i2c_addr: address to store the device i2c address
  180. * @argc: count of command line arguments left to parse
  181. * @argv: command line arguments left to parse
  182. * @argc_no_bus_addr: argc value we expect to see when bus & addr aren't given
  183. *
  184. * @returns: number of arguments parsed or CMD_RET_USAGE if error
  185. */
  186. static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
  187. char *const argv[], int argc_no_bus_addr)
  188. {
  189. int argc_no_bus = argc_no_bus_addr + 1;
  190. int argc_bus_addr = argc_no_bus_addr + 2;
  191. #ifdef CONFIG_SYS_I2C_EEPROM_ADDR
  192. if (argc == argc_no_bus_addr) {
  193. *i2c_bus = -1;
  194. *i2c_addr = CONFIG_SYS_I2C_EEPROM_ADDR;
  195. return 0;
  196. }
  197. #endif
  198. if (argc == argc_no_bus) {
  199. *i2c_bus = -1;
  200. *i2c_addr = parse_numeric_param(argv[0]);
  201. return 1;
  202. }
  203. if (argc == argc_bus_addr) {
  204. *i2c_bus = parse_numeric_param(argv[0]);
  205. *i2c_addr = parse_numeric_param(argv[1]);
  206. return 2;
  207. }
  208. return CMD_RET_USAGE;
  209. }
  210. #ifdef CONFIG_CMD_EEPROM_LAYOUT
  211. __weak int eeprom_parse_layout_version(char *str)
  212. {
  213. return LAYOUT_VERSION_UNRECOGNIZED;
  214. }
  215. static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
  216. #endif
  217. enum eeprom_action {
  218. EEPROM_READ,
  219. EEPROM_WRITE,
  220. EEPROM_PRINT,
  221. EEPROM_UPDATE,
  222. EEPROM_ACTION_INVALID,
  223. };
  224. static enum eeprom_action parse_action(char *cmd)
  225. {
  226. if (!strncmp(cmd, "read", 4))
  227. return EEPROM_READ;
  228. if (!strncmp(cmd, "write", 5))
  229. return EEPROM_WRITE;
  230. #ifdef CONFIG_CMD_EEPROM_LAYOUT
  231. if (!strncmp(cmd, "print", 5))
  232. return EEPROM_PRINT;
  233. if (!strncmp(cmd, "update", 6))
  234. return EEPROM_UPDATE;
  235. #endif
  236. return EEPROM_ACTION_INVALID;
  237. }
  238. static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,
  239. ulong i2c_addr, int layout_ver, char *key,
  240. char *value, ulong addr, ulong off, ulong cnt)
  241. {
  242. int rcode = 0;
  243. const char *const fmt =
  244. "\nEEPROM @0x%lX %s: addr 0x%08lx off 0x%04lx count %ld ... ";
  245. #ifdef CONFIG_CMD_EEPROM_LAYOUT
  246. struct eeprom_layout layout;
  247. #endif
  248. if (action == EEPROM_ACTION_INVALID)
  249. return CMD_RET_USAGE;
  250. eeprom_init(i2c_bus);
  251. if (action == EEPROM_READ) {
  252. printf(fmt, i2c_addr, "read", addr, off, cnt);
  253. rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
  254. puts("done\n");
  255. return rcode;
  256. } else if (action == EEPROM_WRITE) {
  257. printf(fmt, i2c_addr, "write", addr, off, cnt);
  258. rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
  259. puts("done\n");
  260. return rcode;
  261. }
  262. #ifdef CONFIG_CMD_EEPROM_LAYOUT
  263. rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
  264. if (rcode < 0)
  265. return rcode;
  266. eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
  267. layout_ver);
  268. if (action == EEPROM_PRINT) {
  269. layout.print(&layout);
  270. return 0;
  271. }
  272. layout.update(&layout, key, value);
  273. rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);
  274. #endif
  275. return rcode;
  276. }
  277. #define NEXT_PARAM(argc, index) { (argc)--; (index)++; }
  278. int do_eeprom(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
  279. {
  280. int layout_ver = LAYOUT_VERSION_AUTODETECT;
  281. enum eeprom_action action = EEPROM_ACTION_INVALID;
  282. int i2c_bus = -1, index = 0;
  283. ulong i2c_addr = -1, addr = 0, cnt = 0, off = 0;
  284. int ret;
  285. char *field_name = "";
  286. char *field_value = "";
  287. if (argc <= 1)
  288. return CMD_RET_USAGE;
  289. NEXT_PARAM(argc, index); /* Skip program name */
  290. action = parse_action(argv[index]);
  291. NEXT_PARAM(argc, index);
  292. if (action == EEPROM_ACTION_INVALID)
  293. return CMD_RET_USAGE;
  294. #ifdef CONFIG_CMD_EEPROM_LAYOUT
  295. if (action == EEPROM_PRINT || action == EEPROM_UPDATE) {
  296. if (!strcmp(argv[index], "-l")) {
  297. NEXT_PARAM(argc, index);
  298. layout_ver = eeprom_parse_layout_version(argv[index]);
  299. NEXT_PARAM(argc, index);
  300. }
  301. }
  302. #endif
  303. switch (action) {
  304. case EEPROM_READ:
  305. case EEPROM_WRITE:
  306. ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
  307. argv + index, 3);
  308. break;
  309. case EEPROM_PRINT:
  310. ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
  311. argv + index, 0);
  312. break;
  313. case EEPROM_UPDATE:
  314. ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
  315. argv + index, 2);
  316. break;
  317. default:
  318. /* Get compiler to stop whining */
  319. return CMD_RET_USAGE;
  320. }
  321. if (ret == CMD_RET_USAGE)
  322. return ret;
  323. while (ret--)
  324. NEXT_PARAM(argc, index);
  325. if (action == EEPROM_READ || action == EEPROM_WRITE) {
  326. addr = parse_numeric_param(argv[index]);
  327. NEXT_PARAM(argc, index);
  328. off = parse_numeric_param(argv[index]);
  329. NEXT_PARAM(argc, index);
  330. cnt = parse_numeric_param(argv[index]);
  331. }
  332. #ifdef CONFIG_CMD_EEPROM_LAYOUT
  333. if (action == EEPROM_UPDATE) {
  334. field_name = argv[index];
  335. NEXT_PARAM(argc, index);
  336. field_value = argv[index];
  337. NEXT_PARAM(argc, index);
  338. }
  339. #endif
  340. return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
  341. field_name, field_value, addr, off, cnt);
  342. }
  343. U_BOOT_CMD(
  344. eeprom, 8, 1, do_eeprom,
  345. "EEPROM sub-system",
  346. "read <bus> <devaddr> addr off cnt\n"
  347. "eeprom write <bus> <devaddr> addr off cnt\n"
  348. " - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
  349. #ifdef CONFIG_CMD_EEPROM_LAYOUT
  350. "\n"
  351. "eeprom print [-l <layout_version>] <bus> <devaddr>\n"
  352. " - Print layout fields and their data in human readable format\n"
  353. "eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value\n"
  354. " - Update a specific eeprom field with new data.\n"
  355. " The new data must be written in the same human readable format as shown by the print command.\n"
  356. "\n"
  357. "LAYOUT VERSIONS\n"
  358. "The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.\n"
  359. "If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.\n"
  360. "The values which can be provided with the -l option are:\n"
  361. CONFIG_EEPROM_LAYOUT_HELP_STRING"\n"
  362. #endif
  363. )