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 CONFIG_SYS_I2C_SPEED
  31 #define CONFIG_SYS_I2C_SPEED    50000
  32 #endif
  33
  34 #ifndef I2C_RXTX_LEN
  35 #define I2C_RXTX_LEN    128
  36 #endif
  37
  38 #define EEPROM_PAGE_SIZE        (1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)
  39 #define EEPROM_PAGE_OFFSET(x)   ((x) & (EEPROM_PAGE_SIZE - 1))
  40
  41 #if CONFIG_IS_ENABLED(DM_I2C)
  42 static int eeprom_i2c_bus;
  43 #endif
  44
  45 __weak int eeprom_write_enable(unsigned dev_addr, int state)
  46 {
  47         return 0;
  48 }
  49
  50 void eeprom_init(int bus)
  51 {
  52         /* I2C EEPROM */
  53 #if CONFIG_IS_ENABLED(DM_I2C)
  54         eeprom_i2c_bus = bus;
  55 #elif defined(CONFIG_SYS_I2C_LEGACY)
  56         if (bus >= 0)
  57                 i2c_set_bus_num(bus);
  58         i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
  59 #endif
  60 }
  61
  62 /*
  63  * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
  64  *   0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
  65  *
  66  * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
  67  *   0x00000nxx for EEPROM address selectors and page number at n.
  68  */
  69 static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
  70 {
  71         unsigned blk_off;
  72         int alen;
  73
  74         blk_off = offset & 0xff;        /* block offset */
  75 #if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1
  76         addr[0] = offset >> 8;          /* block number */
  77         addr[1] = blk_off;              /* block offset */
  78         alen = 2;
  79 #else
  80         addr[0] = offset >> 16;         /* block number */
  81         addr[1] = offset >>  8;         /* upper address octet */
  82         addr[2] = blk_off;              /* lower address octet */
  83         alen = 3;
  84 #endif  /* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
  85
  86         addr[0] |= dev_addr;            /* insert device address */
  87
  88         return alen;
  89 }
  90
  91 static int eeprom_len(unsigned offset, unsigned end)
  92 {
  93         unsigned len = end - offset;
  94
  95         /*
  96          * For a FRAM device there is no limit on the number of the
  97          * bytes that can be accessed with the single read or write
  98          * operation.
  99          */
 100 #if !defined(CONFIG_SYS_I2C_FRAM)
 101         unsigned blk_off = offset & 0xff;
 102         unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
 103
 104         if (maxlen > I2C_RXTX_LEN)
 105                 maxlen = I2C_RXTX_LEN;
 106
 107         if (len > maxlen)
 108                 len = maxlen;
 109 #endif
 110
 111         return len;
 112 }
 113
 114 static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
 115                            uchar *buffer, unsigned len, bool read)
 116 {
 117         int ret = 0;
 118
 119 #if CONFIG_IS_ENABLED(DM_I2C)
 120         struct udevice *dev;
 121
 122         ret = i2c_get_chip_for_busnum(eeprom_i2c_bus, addr[0],
 123                                       alen - 1, &dev);
 124         if (ret) {
 125                 printf("%s: Cannot find udev for a bus %d\n", __func__,
 126                        eeprom_i2c_bus);
 127                 return CMD_RET_FAILURE;
 128         }
 129
 130         if (read)
 131                 ret = dm_i2c_read(dev, offset, buffer, len);
 132         else
 133                 ret = dm_i2c_write(dev, offset, buffer, len);
 134
 135 #else /* Non DM I2C support - will be removed */
 136
 137         if (read)
 138                 ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
 139         else
 140                 ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
 141 #endif /* CONFIG_DM_I2C */
 142         if (ret)
 143                 ret = CMD_RET_FAILURE;
 144
 145         return ret;
 146 }
 147
 148 static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
 149                      unsigned cnt, bool read)
 150 {
 151         unsigned end = offset + cnt;
 152         unsigned alen, len;
 153         int rcode = 0;
 154         uchar addr[3];
 155
 156 #if defined(CONFIG_SYS_I2C_EEPROM_BUS)
 157         eeprom_init(CONFIG_SYS_I2C_EEPROM_BUS);
 158 #endif
 159
 160         while (offset < end) {
 161                 alen = eeprom_addr(dev_addr, offset, addr);
 162
 163                 len = eeprom_len(offset, end);
 164
 165                 rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
 166
 167                 buffer += len;
 168                 offset += len;
 169
 170 #if CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS > 0
 171                 if (!read)
 172                         udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
 173 #endif
 174         }
 175
 176         return rcode;
 177 }
 178
 179 int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
 180 {
 181         /*
 182          * Read data until done or would cross a page boundary.
 183          * We must write the address again when changing pages
 184          * because the next page may be in a different device.
 185          */
 186         return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
 187 }
 188
 189 int eeprom_write(unsigned dev_addr, unsigned offset,
 190                  uchar *buffer, unsigned cnt)
 191 {
 192         int ret;
 193
 194         eeprom_write_enable(dev_addr, 1);
 195
 196         /*
 197          * Write data until done or would cross a write page boundary.
 198          * We must write the address again when changing pages
 199          * because the address counter only increments within a page.
 200          */
 201         ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
 202
 203         eeprom_write_enable(dev_addr, 0);
 204         return ret;
 205 }
 206
 207 static int parse_numeric_param(char *str)
 208 {
 209         char *endptr;
 210         int value = simple_strtol(str, &endptr, 16);
 211
 212         return (*endptr != '\0') ? -1 : value;
 213 }
 214
 215 /**
 216  * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
 217  *
 218  * @i2c_bus:    address to store the i2c bus
 219  * @i2c_addr:   address to store the device i2c address
 220  * @argc:       count of command line arguments left to parse
 221  * @argv:       command line arguments left to parse
 222  * @argc_no_bus_addr:   argc value we expect to see when bus & addr aren't given
 223  *
 224  * @returns:    number of arguments parsed or CMD_RET_USAGE if error
 225  */
 226 static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
 227                               char *const argv[], int argc_no_bus_addr)
 228 {
 229         int argc_no_bus = argc_no_bus_addr + 1;
 230         int argc_bus_addr = argc_no_bus_addr + 2;
 231
 232 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR
 233         if (argc == argc_no_bus_addr) {
 234                 *i2c_bus = -1;
 235                 *i2c_addr = CONFIG_SYS_I2C_EEPROM_ADDR;
 236
 237                 return 0;
 238         }
 239 #endif
 240         if (argc == argc_no_bus) {
 241                 *i2c_bus = -1;
 242                 *i2c_addr = parse_numeric_param(argv[0]);
 243
 244                 return 1;
 245         }
 246
 247         if (argc == argc_bus_addr) {
 248                 *i2c_bus = parse_numeric_param(argv[0]);
 249                 *i2c_addr = parse_numeric_param(argv[1]);
 250
 251                 return 2;
 252         }
 253
 254         return CMD_RET_USAGE;
 255 }
 256
 257 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 258
 259 __weak int eeprom_parse_layout_version(char *str)
 260 {
 261         return LAYOUT_VERSION_UNRECOGNIZED;
 262 }
 263
 264 static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
 265
 266 #endif
 267
 268 enum eeprom_action {
 269         EEPROM_READ,
 270         EEPROM_WRITE,
 271         EEPROM_PRINT,
 272         EEPROM_UPDATE,
 273         EEPROM_ACTION_INVALID,
 274 };
 275
 276 static enum eeprom_action parse_action(char *cmd)
 277 {
 278         if (!strncmp(cmd, "read", 4))
 279                 return EEPROM_READ;
 280         if (!strncmp(cmd, "write", 5))
 281                 return EEPROM_WRITE;
 282 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 283         if (!strncmp(cmd, "print", 5))
 284                 return EEPROM_PRINT;
 285         if (!strncmp(cmd, "update", 6))
 286                 return EEPROM_UPDATE;
 287 #endif
 288
 289         return EEPROM_ACTION_INVALID;
 290 }
 291
 292 static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,
 293                                   ulong i2c_addr, int layout_ver, char *key,
 294                                   char *value, ulong addr, ulong off, ulong cnt)
 295 {
 296         int rcode = 0;
 297         const char *const fmt =
 298                 "\nEEPROM @0x%lX %s: addr 0x%08lx  off 0x%04lx  count %ld ... ";
 299 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 300         struct eeprom_layout layout;
 301 #endif
 302
 303         if (action == EEPROM_ACTION_INVALID)
 304                 return CMD_RET_USAGE;
 305
 306         eeprom_init(i2c_bus);
 307         if (action == EEPROM_READ) {
 308                 printf(fmt, i2c_addr, "read", addr, off, cnt);
 309
 310                 rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
 311
 312                 puts("done\n");
 313                 return rcode;
 314         } else if (action == EEPROM_WRITE) {
 315                 printf(fmt, i2c_addr, "write", addr, off, cnt);
 316
 317                 rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
 318
 319                 puts("done\n");
 320                 return rcode;
 321         }
 322
 323 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 324         rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
 325         if (rcode < 0)
 326                 return rcode;
 327
 328         eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
 329                             layout_ver);
 330
 331         if (action == EEPROM_PRINT) {
 332                 layout.print(&layout);
 333                 return 0;
 334         }
 335
 336         layout.update(&layout, key, value);
 337
 338         rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);
 339 #endif
 340
 341         return rcode;
 342 }
 343
 344 #define NEXT_PARAM(argc, index) { (argc)--; (index)++; }
 345 int do_eeprom(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
 346 {
 347         int layout_ver = LAYOUT_VERSION_AUTODETECT;
 348         enum eeprom_action action = EEPROM_ACTION_INVALID;
 349         int i2c_bus = -1, index = 0;
 350         ulong i2c_addr = -1, addr = 0, cnt = 0, off = 0;
 351         int ret;
 352         char *field_name = "";
 353         char *field_value = "";
 354
 355         if (argc <= 1)
 356                 return CMD_RET_USAGE;
 357
 358         NEXT_PARAM(argc, index); /* Skip program name */
 359
 360         action = parse_action(argv[index]);
 361         NEXT_PARAM(argc, index);
 362
 363         if (action == EEPROM_ACTION_INVALID)
 364                 return CMD_RET_USAGE;
 365
 366 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 367         if (action == EEPROM_PRINT || action == EEPROM_UPDATE) {
 368                 if (!strcmp(argv[index], "-l")) {
 369                         NEXT_PARAM(argc, index);
 370                         layout_ver = eeprom_parse_layout_version(argv[index]);
 371                         NEXT_PARAM(argc, index);
 372                 }
 373         }
 374 #endif
 375
 376         switch (action) {
 377         case EEPROM_READ:
 378         case EEPROM_WRITE:
 379                 ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
 380                                          argv + index, 3);
 381                 break;
 382         case EEPROM_PRINT:
 383                 ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
 384                                          argv + index, 0);
 385                 break;
 386         case EEPROM_UPDATE:
 387                 ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
 388                                          argv + index, 2);
 389                 break;
 390         default:
 391                 /* Get compiler to stop whining */
 392                 return CMD_RET_USAGE;
 393         }
 394
 395         if (ret == CMD_RET_USAGE)
 396                 return ret;
 397
 398         while (ret--)
 399                 NEXT_PARAM(argc, index);
 400
 401         if (action == EEPROM_READ || action == EEPROM_WRITE) {
 402                 addr = parse_numeric_param(argv[index]);
 403                 NEXT_PARAM(argc, index);
 404                 off = parse_numeric_param(argv[index]);
 405                 NEXT_PARAM(argc, index);
 406                 cnt = parse_numeric_param(argv[index]);
 407         }
 408
 409 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 410         if (action == EEPROM_UPDATE) {
 411                 field_name = argv[index];
 412                 NEXT_PARAM(argc, index);
 413                 field_value = argv[index];
 414                 NEXT_PARAM(argc, index);
 415         }
 416 #endif
 417
 418         return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
 419                                       field_name, field_value, addr, off, cnt);
 420 }
 421
 422 U_BOOT_CMD(
 423         eeprom, 8,      1,      do_eeprom,
 424         "EEPROM sub-system",
 425         "read  <bus> <devaddr> addr off cnt\n"
 426         "eeprom write <bus> <devaddr> addr off cnt\n"
 427         "       - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
 428 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 429         "\n"
 430         "eeprom print [-l <layout_version>] <bus> <devaddr>\n"
 431         "       - Print layout fields and their data in human readable format\n"
 432         "eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value\n"
 433         "       - Update a specific eeprom field with new data.\n"
 434         "         The new data must be written in the same human readable format as shown by the print command.\n"
 435         "\n"
 436         "LAYOUT VERSIONS\n"
 437         "The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.\n"
 438         "If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.\n"
 439         "The values which can be provided with the -l option are:\n"
 440         CONFIG_EEPROM_LAYOUT_HELP_STRING"\n"
 441 #endif
 442 )