cmd/eeprom.c

   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 /*
   8  * Support for read and write access to EEPROM like memory devices. This
   9  * includes regular EEPROM as well as  FRAM (ferroelectic nonvolaile RAM).
  10  * FRAM devices read and write data at bus speed. In particular, there is no
  11  * write delay. Also, there is no limit imposed on the number of bytes that can
  12  * be transferred with a single read or write.
  13  *
  14  * Use the following configuration options to ensure no unneeded performance
  15  * degradation (typical for EEPROM) is incured for FRAM memory:
  16  *
  17  * #define CONFIG_SYS_I2C_FRAM
  18  * Set CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS to 0
  19  *
  20  */
  21
  22 #include <common.h>
  23 #include <config.h>
  24 #include <command.h>
  25 #include <eeprom.h>
  26 #include <i2c.h>
  27 #include <eeprom_layout.h>
  28 #include <linux/delay.h>
  29
  30 #ifndef I2C_RXTX_LEN
  31 #define I2C_RXTX_LEN    128
  32 #endif
  33
  34 #define EEPROM_PAGE_SIZE        (1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)
  35 #define EEPROM_PAGE_OFFSET(x)   ((x) & (EEPROM_PAGE_SIZE - 1))
  36
  37 #if CONFIG_IS_ENABLED(DM_I2C)
  38 static int eeprom_i2c_bus;
  39 #endif
  40
  41 __weak int eeprom_write_enable(unsigned dev_addr, int state)
  42 {
  43         return 0;
  44 }
  45
  46 void eeprom_init(int bus)
  47 {
  48         /* I2C EEPROM */
  49 #if CONFIG_IS_ENABLED(DM_I2C)
  50         eeprom_i2c_bus = bus;
  51 #elif CONFIG_IS_ENABLED(SYS_I2C_LEGACY)
  52         if (bus >= 0)
  53                 i2c_set_bus_num(bus);
  54         i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
  55 #endif
  56 }
  57
  58 /*
  59  * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
  60  *   0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
  61  *
  62  * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
  63  *   0x00000nxx for EEPROM address selectors and page number at n.
  64  */
  65 static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
  66 {
  67         unsigned blk_off;
  68         int alen;
  69
  70         blk_off = offset & 0xff;        /* block offset */
  71 #if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1
  72         addr[0] = offset >> 8;          /* block number */
  73         addr[1] = blk_off;              /* block offset */
  74         alen = 2;
  75 #else
  76         addr[0] = offset >> 16;         /* block number */
  77         addr[1] = offset >>  8;         /* upper address octet */
  78         addr[2] = blk_off;              /* lower address octet */
  79         alen = 3;
  80 #endif  /* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
  81
  82         addr[0] |= dev_addr;            /* insert device address */
  83
  84         return alen;
  85 }
  86
  87 static int eeprom_len(unsigned offset, unsigned end)
  88 {
  89         unsigned len = end - offset;
  90
  91         /*
  92          * For a FRAM device there is no limit on the number of the
  93          * bytes that can be accessed with the single read or write
  94          * operation.
  95          */
  96 #if !defined(CONFIG_SYS_I2C_FRAM)
  97         unsigned blk_off = offset & 0xff;
  98         unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
  99
 100         if (maxlen > I2C_RXTX_LEN)
 101                 maxlen = I2C_RXTX_LEN;
 102
 103         if (len > maxlen)
 104                 len = maxlen;
 105 #endif
 106
 107         return len;
 108 }
 109
 110 static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
 111                            uchar *buffer, unsigned len, bool read)
 112 {
 113         int ret = 0;
 114
 115 #if CONFIG_IS_ENABLED(DM_I2C)
 116         struct udevice *dev;
 117
 118         ret = i2c_get_chip_for_busnum(eeprom_i2c_bus, addr[0],
 119                                       alen - 1, &dev);
 120         if (ret) {
 121                 printf("%s: Cannot find udev for a bus %d\n", __func__,
 122                        eeprom_i2c_bus);
 123                 return CMD_RET_FAILURE;
 124         }
 125
 126         if (read)
 127                 ret = dm_i2c_read(dev, offset, buffer, len);
 128         else
 129                 ret = dm_i2c_write(dev, offset, buffer, len);
 130
 131 #else /* Non DM I2C support - will be removed */
 132
 133         if (read)
 134                 ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
 135         else
 136                 ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
 137 #endif /* CONFIG_DM_I2C */
 138         if (ret)
 139                 ret = CMD_RET_FAILURE;
 140
 141         return ret;
 142 }
 143
 144 static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
 145                      unsigned cnt, bool read)
 146 {
 147         unsigned end = offset + cnt;
 148         unsigned alen, len;
 149         int rcode = 0;
 150         uchar addr[3];
 151
 152 #if defined(CONFIG_SYS_I2C_EEPROM_BUS)
 153         eeprom_init(CONFIG_SYS_I2C_EEPROM_BUS);
 154 #endif
 155
 156         while (offset < end) {
 157                 alen = eeprom_addr(dev_addr, offset, addr);
 158
 159                 len = eeprom_len(offset, end);
 160
 161                 rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
 162
 163                 buffer += len;
 164                 offset += len;
 165
 166 #if CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS > 0
 167                 if (!read)
 168                         udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
 169 #endif
 170         }
 171
 172         return rcode;
 173 }
 174
 175 int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
 176 {
 177         /*
 178          * Read data until done or would cross a page boundary.
 179          * We must write the address again when changing pages
 180          * because the next page may be in a different device.
 181          */
 182         return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
 183 }
 184
 185 int eeprom_write(unsigned dev_addr, unsigned offset,
 186                  uchar *buffer, unsigned cnt)
 187 {
 188         int ret;
 189
 190         eeprom_write_enable(dev_addr, 1);
 191
 192         /*
 193          * Write data until done or would cross a write page boundary.
 194          * We must write the address again when changing pages
 195          * because the address counter only increments within a page.
 196          */
 197         ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
 198
 199         eeprom_write_enable(dev_addr, 0);
 200         return ret;
 201 }
 202
 203 static int parse_numeric_param(char *str)
 204 {
 205         char *endptr;
 206         int value = simple_strtol(str, &endptr, 16);
 207
 208         return (*endptr != '\0') ? -1 : value;
 209 }
 210
 211 /**
 212  * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
 213  *
 214  * @i2c_bus:    address to store the i2c bus
 215  * @i2c_addr:   address to store the device i2c address
 216  * @argc:       count of command line arguments left to parse
 217  * @argv:       command line arguments left to parse
 218  * @argc_no_bus_addr:   argc value we expect to see when bus & addr aren't given
 219  *
 220  * @returns:    number of arguments parsed or CMD_RET_USAGE if error
 221  */
 222 static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
 223                               char *const argv[], int argc_no_bus_addr)
 224 {
 225         int argc_no_bus = argc_no_bus_addr + 1;
 226         int argc_bus_addr = argc_no_bus_addr + 2;
 227
 228 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR
 229         if (argc == argc_no_bus_addr) {
 230                 *i2c_bus = -1;
 231                 *i2c_addr = CONFIG_SYS_I2C_EEPROM_ADDR;
 232
 233                 return 0;
 234         }
 235 #endif
 236         if (argc == argc_no_bus) {
 237                 *i2c_bus = -1;
 238                 *i2c_addr = parse_numeric_param(argv[0]);
 239
 240                 return 1;
 241         }
 242
 243         if (argc == argc_bus_addr) {
 244                 *i2c_bus = parse_numeric_param(argv[0]);
 245                 *i2c_addr = parse_numeric_param(argv[1]);
 246
 247                 return 2;
 248         }
 249
 250         return CMD_RET_USAGE;
 251 }
 252
 253 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 254
 255 __weak int eeprom_parse_layout_version(char *str)
 256 {
 257         return LAYOUT_VERSION_UNRECOGNIZED;
 258 }
 259
 260 static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
 261
 262 #endif
 263
 264 enum eeprom_action {
 265         EEPROM_READ,
 266         EEPROM_WRITE,
 267         EEPROM_PRINT,
 268         EEPROM_UPDATE,
 269         EEPROM_ACTION_INVALID,
 270 };
 271
 272 static enum eeprom_action parse_action(char *cmd)
 273 {
 274         if (!strncmp(cmd, "read", 4))
 275                 return EEPROM_READ;
 276         if (!strncmp(cmd, "write", 5))
 277                 return EEPROM_WRITE;
 278 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 279         if (!strncmp(cmd, "print", 5))
 280                 return EEPROM_PRINT;
 281         if (!strncmp(cmd, "update", 6))
 282                 return EEPROM_UPDATE;
 283 #endif
 284
 285         return EEPROM_ACTION_INVALID;
 286 }
 287
 288 static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,
 289                                   ulong i2c_addr, int layout_ver, char *key,
 290                                   char *value, ulong addr, ulong off, ulong cnt)
 291 {
 292         int rcode = 0;
 293         const char *const fmt =
 294                 "\nEEPROM @0x%lX %s: addr 0x%08lx  off 0x%04lx  count %ld ... ";
 295 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 296         struct eeprom_layout layout;
 297 #endif
 298
 299         if (action == EEPROM_ACTION_INVALID)
 300                 return CMD_RET_USAGE;
 301
 302         eeprom_init(i2c_bus);
 303         if (action == EEPROM_READ) {
 304                 printf(fmt, i2c_addr, "read", addr, off, cnt);
 305
 306                 rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
 307
 308                 puts("done\n");
 309                 return rcode;
 310         } else if (action == EEPROM_WRITE) {
 311                 printf(fmt, i2c_addr, "write", addr, off, cnt);
 312
 313                 rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
 314
 315                 puts("done\n");
 316                 return rcode;
 317         }
 318
 319 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 320         rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
 321         if (rcode < 0)
 322                 return rcode;
 323
 324         eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
 325                             layout_ver);
 326
 327         if (action == EEPROM_PRINT) {
 328                 layout.print(&layout);
 329                 return 0;
 330         }
 331
 332         layout.update(&layout, key, value);
 333
 334         rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);
 335 #endif
 336
 337         return rcode;
 338 }
 339
 340 #define NEXT_PARAM(argc, index) { (argc)--; (index)++; }
 341 int do_eeprom(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
 342 {
 343         int layout_ver = LAYOUT_VERSION_AUTODETECT;
 344         enum eeprom_action action = EEPROM_ACTION_INVALID;
 345         int i2c_bus = -1, index = 0;
 346         ulong i2c_addr = -1, addr = 0, cnt = 0, off = 0;
 347         int ret;
 348         char *field_name = "";
 349         char *field_value = "";
 350
 351         if (argc <= 1)
 352                 return CMD_RET_USAGE;
 353
 354         NEXT_PARAM(argc, index); /* Skip program name */
 355
 356         action = parse_action(argv[index]);
 357         NEXT_PARAM(argc, index);
 358
 359         if (action == EEPROM_ACTION_INVALID)
 360                 return CMD_RET_USAGE;
 361
 362 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 363         if (action == EEPROM_PRINT || action == EEPROM_UPDATE) {
 364                 if (!strcmp(argv[index], "-l")) {
 365                         NEXT_PARAM(argc, index);
 366                         layout_ver = eeprom_parse_layout_version(argv[index]);
 367                         NEXT_PARAM(argc, index);
 368                 }
 369         }
 370 #endif
 371
 372         switch (action) {
 373         case EEPROM_READ:
 374         case EEPROM_WRITE:
 375                 ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
 376                                          argv + index, 3);
 377                 break;
 378         case EEPROM_PRINT:
 379                 ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
 380                                          argv + index, 0);
 381                 break;
 382         case EEPROM_UPDATE:
 383                 ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
 384                                          argv + index, 2);
 385                 break;
 386         default:
 387                 /* Get compiler to stop whining */
 388                 return CMD_RET_USAGE;
 389         }
 390
 391         if (ret == CMD_RET_USAGE)
 392                 return ret;
 393
 394         while (ret--)
 395                 NEXT_PARAM(argc, index);
 396
 397         if (action == EEPROM_READ || action == EEPROM_WRITE) {
 398                 addr = parse_numeric_param(argv[index]);
 399                 NEXT_PARAM(argc, index);
 400                 off = parse_numeric_param(argv[index]);
 401                 NEXT_PARAM(argc, index);
 402                 cnt = parse_numeric_param(argv[index]);
 403         }
 404
 405 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 406         if (action == EEPROM_UPDATE) {
 407                 field_name = argv[index];
 408                 NEXT_PARAM(argc, index);
 409                 field_value = argv[index];
 410                 NEXT_PARAM(argc, index);
 411         }
 412 #endif
 413
 414         return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
 415                                       field_name, field_value, addr, off, cnt);
 416 }
 417
 418 U_BOOT_CMD(
 419         eeprom, 8,      1,      do_eeprom,
 420         "EEPROM sub-system",
 421         "read  <bus> <devaddr> addr off cnt\n"
 422         "eeprom write <bus> <devaddr> addr off cnt\n"
 423         "       - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
 424 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 425         "\n"
 426         "eeprom print [-l <layout_version>] <bus> <devaddr>\n"
 427         "       - Print layout fields and their data in human readable format\n"
 428         "eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value\n"
 429         "       - Update a specific eeprom field with new data.\n"
 430         "         The new data must be written in the same human readable format as shown by the print command.\n"
 431         "\n"
 432         "LAYOUT VERSIONS\n"
 433         "The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.\n"
 434         "If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.\n"
 435         "The values which can be provided with the -l option are:\n"
 436         CONFIG_EEPROM_LAYOUT_HELP_STRING"\n"
 437 #endif
 438 )