eeprom.c 5.4 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241
  1. // SPDX-License-Identifier: GPL-2.0+
  2. /*
  3. * (C) Copyright 2000-2010
  4. * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  5. *
  6. * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
  7. * Andreas Heppel <aheppel@sysgo.de>
  8. */
  9. #include <common.h>
  10. #include <command.h>
  11. #include <eeprom.h>
  12. #include <env.h>
  13. #include <env_internal.h>
  14. #include <asm/global_data.h>
  15. #include <linux/stddef.h>
  16. #include <u-boot/crc.h>
  17. #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
  18. #include <i2c.h>
  19. #endif
  20. #include <search.h>
  21. #include <errno.h>
  22. #include <linux/compiler.h> /* for BUG_ON */
  23. DECLARE_GLOBAL_DATA_PTR;
  24. static int eeprom_bus_read(unsigned dev_addr, unsigned offset,
  25. uchar *buffer, unsigned cnt)
  26. {
  27. int rcode;
  28. #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
  29. int old_bus = i2c_get_bus_num();
  30. if (old_bus != CONFIG_I2C_ENV_EEPROM_BUS)
  31. i2c_set_bus_num(CONFIG_I2C_ENV_EEPROM_BUS);
  32. #endif
  33. rcode = eeprom_read(dev_addr, offset, buffer, cnt);
  34. #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
  35. i2c_set_bus_num(old_bus);
  36. #endif
  37. return rcode;
  38. }
  39. static int eeprom_bus_write(unsigned dev_addr, unsigned offset,
  40. uchar *buffer, unsigned cnt)
  41. {
  42. int rcode;
  43. #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
  44. int old_bus = i2c_get_bus_num();
  45. if (old_bus != CONFIG_I2C_ENV_EEPROM_BUS)
  46. i2c_set_bus_num(CONFIG_I2C_ENV_EEPROM_BUS);
  47. #endif
  48. rcode = eeprom_write(dev_addr, offset, buffer, cnt);
  49. #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
  50. i2c_set_bus_num(old_bus);
  51. #endif
  52. return rcode;
  53. }
  54. /** Call this function from overridden env_get_char_spec() if you need
  55. * this functionality.
  56. */
  57. int env_eeprom_get_char(int index)
  58. {
  59. uchar c;
  60. unsigned int off = CONFIG_ENV_OFFSET;
  61. #ifdef CONFIG_ENV_OFFSET_REDUND
  62. if (gd->env_valid == ENV_REDUND)
  63. off = CONFIG_ENV_OFFSET_REDUND;
  64. #endif
  65. eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
  66. off + index + offsetof(env_t, data), &c, 1);
  67. return c;
  68. }
  69. static int env_eeprom_load(void)
  70. {
  71. char buf_env[CONFIG_ENV_SIZE];
  72. unsigned int off = CONFIG_ENV_OFFSET;
  73. #ifdef CONFIG_ENV_OFFSET_REDUND
  74. ulong len, crc[2], crc_tmp;
  75. unsigned int off_env[2];
  76. uchar rdbuf[64], flags[2];
  77. int i, crc_ok[2] = {0, 0};
  78. eeprom_init(-1); /* prepare for EEPROM read/write */
  79. off_env[0] = CONFIG_ENV_OFFSET;
  80. off_env[1] = CONFIG_ENV_OFFSET_REDUND;
  81. for (i = 0; i < 2; i++) {
  82. /* read CRC */
  83. eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
  84. off_env[i] + offsetof(env_t, crc),
  85. (uchar *)&crc[i], sizeof(ulong));
  86. /* read FLAGS */
  87. eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
  88. off_env[i] + offsetof(env_t, flags),
  89. (uchar *)&flags[i], sizeof(uchar));
  90. crc_tmp = 0;
  91. len = ENV_SIZE;
  92. off = off_env[i] + offsetof(env_t, data);
  93. while (len > 0) {
  94. int n = (len > sizeof(rdbuf)) ? sizeof(rdbuf) : len;
  95. eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR, off,
  96. rdbuf, n);
  97. crc_tmp = crc32(crc_tmp, rdbuf, n);
  98. len -= n;
  99. off += n;
  100. }
  101. if (crc_tmp == crc[i])
  102. crc_ok[i] = 1;
  103. }
  104. if (!crc_ok[0] && !crc_ok[1]) {
  105. gd->env_addr = 0;
  106. gd->env_valid = ENV_INVALID;
  107. } else if (crc_ok[0] && !crc_ok[1]) {
  108. gd->env_valid = ENV_VALID;
  109. } else if (!crc_ok[0] && crc_ok[1]) {
  110. gd->env_valid = ENV_REDUND;
  111. } else {
  112. /* both ok - check serial */
  113. if (flags[0] == ENV_REDUND_ACTIVE &&
  114. flags[1] == ENV_REDUND_OBSOLETE)
  115. gd->env_valid = ENV_VALID;
  116. else if (flags[0] == ENV_REDUND_OBSOLETE &&
  117. flags[1] == ENV_REDUND_ACTIVE)
  118. gd->env_valid = ENV_REDUND;
  119. else if (flags[0] == 0xFF && flags[1] == 0)
  120. gd->env_valid = ENV_REDUND;
  121. else if (flags[1] == 0xFF && flags[0] == 0)
  122. gd->env_valid = ENV_VALID;
  123. else /* flags are equal - almost impossible */
  124. gd->env_valid = ENV_VALID;
  125. }
  126. #else /* CONFIG_ENV_OFFSET_REDUND */
  127. ulong crc, len, new;
  128. uchar rdbuf[64];
  129. eeprom_init(-1); /* prepare for EEPROM read/write */
  130. /* read old CRC */
  131. eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
  132. CONFIG_ENV_OFFSET + offsetof(env_t, crc),
  133. (uchar *)&crc, sizeof(ulong));
  134. new = 0;
  135. len = ENV_SIZE;
  136. off = offsetof(env_t, data);
  137. while (len > 0) {
  138. int n = (len > sizeof(rdbuf)) ? sizeof(rdbuf) : len;
  139. eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
  140. CONFIG_ENV_OFFSET + off, rdbuf, n);
  141. new = crc32(new, rdbuf, n);
  142. len -= n;
  143. off += n;
  144. }
  145. if (crc == new) {
  146. gd->env_valid = ENV_VALID;
  147. } else {
  148. gd->env_valid = ENV_INVALID;
  149. }
  150. #endif /* CONFIG_ENV_OFFSET_REDUND */
  151. off = CONFIG_ENV_OFFSET;
  152. #ifdef CONFIG_ENV_OFFSET_REDUND
  153. if (gd->env_valid == ENV_REDUND)
  154. off = CONFIG_ENV_OFFSET_REDUND;
  155. #endif
  156. eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
  157. off, (uchar *)buf_env, CONFIG_ENV_SIZE);
  158. return env_import(buf_env, 1, H_EXTERNAL);
  159. }
  160. static int env_eeprom_save(void)
  161. {
  162. env_t env_new;
  163. int rc;
  164. unsigned int off = CONFIG_ENV_OFFSET;
  165. #ifdef CONFIG_ENV_OFFSET_REDUND
  166. unsigned int off_red = CONFIG_ENV_OFFSET_REDUND;
  167. char flag_obsolete = ENV_REDUND_OBSOLETE;
  168. #endif
  169. rc = env_export(&env_new);
  170. if (rc)
  171. return rc;
  172. #ifdef CONFIG_ENV_OFFSET_REDUND
  173. if (gd->env_valid == ENV_VALID) {
  174. off = CONFIG_ENV_OFFSET_REDUND;
  175. off_red = CONFIG_ENV_OFFSET;
  176. }
  177. env_new.flags = ENV_REDUND_ACTIVE;
  178. #endif
  179. rc = eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR,
  180. off, (uchar *)&env_new, CONFIG_ENV_SIZE);
  181. #ifdef CONFIG_ENV_OFFSET_REDUND
  182. if (rc == 0) {
  183. eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR,
  184. off_red + offsetof(env_t, flags),
  185. (uchar *)&flag_obsolete, 1);
  186. if (gd->env_valid == ENV_VALID)
  187. gd->env_valid = ENV_REDUND;
  188. else
  189. gd->env_valid = ENV_VALID;
  190. }
  191. #endif
  192. return rc;
  193. }
  194. U_BOOT_ENV_LOCATION(eeprom) = {
  195. .location = ENVL_EEPROM,
  196. ENV_NAME("EEPROM")
  197. .load = env_eeprom_load,
  198. .save = env_save_ptr(env_eeprom_save),
  199. };