common/cmd_eeprom.c

   1 /*
   2  * (C) Copyright 2000, 2001
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  *
  23  */
  24
  25 /*
  26  * Support for read and write access to EEPROM like memory devices. This
  27  * includes regular EEPROM as well as  FRAM (ferroelectic nonvolaile RAM).
  28  * FRAM devices read and write data at bus speed. In particular, there is no
  29  * write delay. Also, there is no limit imposed on the numer of bytes that can
  30  * be transferred with a single read or write.
  31  *
  32  * Use the following configuration options to ensure no unneeded performance
  33  * degradation (typical for EEPROM) is incured for FRAM memory:
  34  *
  35  * #define CFG_I2C_FRAM
  36  * #undef CFG_EEPROM_PAGE_WRITE_DELAY_MS
  37  *
  38  */
  39
  40 #include <common.h>
  41 #include <config.h>
  42 #include <command.h>
  43 #include <i2c.h>
  44
  45 #if defined(CFG_ENV_IS_IN_EEPROM) || defined(CONFIG_CMD_EEPROM)
  46
  47 extern void eeprom_init  (void);
  48 extern int  eeprom_read  (unsigned dev_addr, unsigned offset,
  49                           uchar *buffer, unsigned cnt);
  50 extern int  eeprom_write (unsigned dev_addr, unsigned offset,
  51                           uchar *buffer, unsigned cnt);
  52 #if defined(CFG_EEPROM_WREN)
  53 extern int eeprom_write_enable (unsigned dev_addr, int state);
  54 #endif
  55 #endif
  56
  57
  58 #if defined(CFG_EEPROM_X40430)
  59         /* Maximum number of times to poll for acknowledge after write */
  60 #define MAX_ACKNOWLEDGE_POLLS   10
  61 #endif
  62
  63 /* ------------------------------------------------------------------------- */
  64
  65 #if defined(CONFIG_CMD_EEPROM)
  66 int do_eeprom ( cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
  67 {
  68         const char *const fmt =
  69                 "\nEEPROM @0x%lX %s: addr %08lx  off %04lx  count %ld ... ";
  70
  71 #if defined(CFG_I2C_MULTI_EEPROMS)
  72         if (argc == 6) {
  73                 ulong dev_addr = simple_strtoul (argv[2], NULL, 16);
  74                 ulong addr = simple_strtoul (argv[3], NULL, 16);
  75                 ulong off  = simple_strtoul (argv[4], NULL, 16);
  76                 ulong cnt  = simple_strtoul (argv[5], NULL, 16);
  77 #else
  78         if (argc == 5) {
  79                 ulong dev_addr = CFG_DEF_EEPROM_ADDR;
  80                 ulong addr = simple_strtoul (argv[2], NULL, 16);
  81                 ulong off  = simple_strtoul (argv[3], NULL, 16);
  82                 ulong cnt  = simple_strtoul (argv[4], NULL, 16);
  83 #endif /* CFG_I2C_MULTI_EEPROMS */
  84
  85 # ifndef CONFIG_SPI
  86                 eeprom_init ();
  87 # endif /* !CONFIG_SPI */
  88
  89                 if (strcmp (argv[1], "read") == 0) {
  90                         int rcode;
  91
  92                         printf (fmt, dev_addr, argv[1], addr, off, cnt);
  93
  94                         rcode = eeprom_read (dev_addr, off, (uchar *) addr, cnt);
  95
  96                         puts ("done\n");
  97                         return rcode;
  98                 } else if (strcmp (argv[1], "write") == 0) {
  99                         int rcode;
 100
 101                         printf (fmt, dev_addr, argv[1], addr, off, cnt);
 102
 103                         rcode = eeprom_write (dev_addr, off, (uchar *) addr, cnt);
 104
 105                         puts ("done\n");
 106                         return rcode;
 107                 }
 108         }
 109
 110         printf ("Usage:\n%s\n", cmdtp->usage);
 111         return 1;
 112 }
 113 #endif
 114
 115 /*-----------------------------------------------------------------------
 116  *
 117  * for CFG_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
 118  *   0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
 119  *
 120  * for CFG_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
 121  *   0x00000nxx for EEPROM address selectors and page number at n.
 122  */
 123
 124 #if defined(CFG_ENV_IS_IN_EEPROM) || defined(CONFIG_CMD_EEPROM)
 125
 126 #ifndef CONFIG_SPI
 127 #if !defined(CFG_I2C_EEPROM_ADDR_LEN) || CFG_I2C_EEPROM_ADDR_LEN < 1 || CFG_I2C_EEPROM_ADDR_LEN > 2
 128 #error CFG_I2C_EEPROM_ADDR_LEN must be 1 or 2
 129 #endif
 130 #endif
 131
 132 int eeprom_read (unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
 133 {
 134         unsigned end = offset + cnt;
 135         unsigned blk_off;
 136         int rcode = 0;
 137
 138         /* Read data until done or would cross a page boundary.
 139          * We must write the address again when changing pages
 140          * because the next page may be in a different device.
 141          */
 142         while (offset < end) {
 143                 unsigned alen, len;
 144 #if !defined(CFG_I2C_FRAM)
 145                 unsigned maxlen;
 146 #endif
 147
 148 #if CFG_I2C_EEPROM_ADDR_LEN == 1 && !defined(CONFIG_SPI_X)
 149                 uchar addr[2];
 150
 151                 blk_off = offset & 0xFF;        /* block offset */
 152
 153                 addr[0] = offset >> 8;          /* block number */
 154                 addr[1] = blk_off;              /* block offset */
 155                 alen    = 2;
 156 #else
 157                 uchar addr[3];
 158
 159                 blk_off = offset & 0xFF;        /* block offset */
 160
 161                 addr[0] = offset >> 16;         /* block number */
 162                 addr[1] = offset >>  8;         /* upper address octet */
 163                 addr[2] = blk_off;              /* lower address octet */
 164                 alen    = 3;
 165 #endif  /* CFG_I2C_EEPROM_ADDR_LEN, CONFIG_SPI_X */
 166
 167                 addr[0] |= dev_addr;            /* insert device address */
 168
 169                 len = end - offset;
 170
 171                 /*
 172                  * For a FRAM device there is no limit on the number of the
 173                  * bytes that can be ccessed with the single read or write
 174                  * operation.
 175                  */
 176 #if !defined(CFG_I2C_FRAM)
 177                 maxlen = 0x100 - blk_off;
 178                 if (maxlen > I2C_RXTX_LEN)
 179                         maxlen = I2C_RXTX_LEN;
 180                 if (len > maxlen)
 181                         len = maxlen;
 182 #endif
 183
 184 #ifdef CONFIG_SPI
 185                 spi_read (addr, alen, buffer, len);
 186 #else
 187                 if (i2c_read (addr[0], offset, alen-1, buffer, len) != 0)
 188                         rcode = 1;
 189 #endif
 190                 buffer += len;
 191                 offset += len;
 192         }
 193
 194         return rcode;
 195 }
 196
 197 /*-----------------------------------------------------------------------
 198  *
 199  * for CFG_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
 200  *   0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
 201  *
 202  * for CFG_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
 203  *   0x00000nxx for EEPROM address selectors and page number at n.
 204  */
 205
 206 int eeprom_write (unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
 207 {
 208         unsigned end = offset + cnt;
 209         unsigned blk_off;
 210         int rcode = 0;
 211
 212 #if defined(CFG_EEPROM_X40430)
 213         uchar   contr_r_addr[2];
 214         uchar   addr_void[2];
 215         uchar   contr_reg[2];
 216         uchar   ctrl_reg_v;
 217         int     i;
 218 #endif
 219
 220 #if defined(CFG_EEPROM_WREN)
 221         eeprom_write_enable (dev_addr,1);
 222 #endif
 223         /* Write data until done or would cross a write page boundary.
 224          * We must write the address again when changing pages
 225          * because the address counter only increments within a page.
 226          */
 227
 228         while (offset < end) {
 229                 unsigned alen, len;
 230 #if !defined(CFG_I2C_FRAM)
 231                 unsigned maxlen;
 232 #endif
 233
 234 #if CFG_I2C_EEPROM_ADDR_LEN == 1 && !defined(CONFIG_SPI_X)
 235                 uchar addr[2];
 236
 237                 blk_off = offset & 0xFF;        /* block offset */
 238
 239                 addr[0] = offset >> 8;          /* block number */
 240                 addr[1] = blk_off;              /* block offset */
 241                 alen    = 2;
 242 #else
 243                 uchar addr[3];
 244
 245                 blk_off = offset & 0xFF;        /* block offset */
 246
 247                 addr[0] = offset >> 16;         /* block number */
 248                 addr[1] = offset >>  8;         /* upper address octet */
 249                 addr[2] = blk_off;              /* lower address octet */
 250                 alen    = 3;
 251 #endif  /* CFG_I2C_EEPROM_ADDR_LEN, CONFIG_SPI_X */
 252
 253                 addr[0] |= dev_addr;            /* insert device address */
 254
 255                 len = end - offset;
 256
 257                 /*
 258                  * For a FRAM device there is no limit on the number of the
 259                  * bytes that can be ccessed with the single read or write
 260                  * operation.
 261                  */
 262 #if !defined(CFG_I2C_FRAM)
 263
 264 #if defined(CFG_EEPROM_PAGE_WRITE_BITS)
 265
 266 #define EEPROM_PAGE_SIZE        (1 << CFG_EEPROM_PAGE_WRITE_BITS)
 267 #define EEPROM_PAGE_OFFSET(x)   ((x) & (EEPROM_PAGE_SIZE - 1))
 268
 269                 maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
 270 #else
 271                 maxlen = 0x100 - blk_off;
 272 #endif
 273                 if (maxlen > I2C_RXTX_LEN)
 274                         maxlen = I2C_RXTX_LEN;
 275
 276                 if (len > maxlen)
 277                         len = maxlen;
 278 #endif
 279
 280 #ifdef CONFIG_SPI
 281                 spi_write (addr, alen, buffer, len);
 282 #else
 283 #if defined(CFG_EEPROM_X40430)
 284                 /* Get the value of the control register.
 285                  * Set current address (internal pointer in the x40430)
 286                  * to 0x1ff.
 287                  */
 288                 contr_r_addr[0] = 9;
 289                 contr_r_addr[1] = 0xff;
 290                 addr_void[0]    = 0;
 291                 addr_void[1]    = addr[1];
 292 #ifdef CFG_I2C_EEPROM_ADDR
 293                 contr_r_addr[0] |= CFG_I2C_EEPROM_ADDR;
 294                 addr_void[0]    |= CFG_I2C_EEPROM_ADDR;
 295 #endif
 296                 contr_reg[0] = 0xff;
 297                 if (i2c_read (contr_r_addr[0], contr_r_addr[1], 1, contr_reg, 1) != 0) {
 298                         rcode = 1;
 299                 }
 300                 ctrl_reg_v = contr_reg[0];
 301
 302                 /* Are any of the eeprom blocks write protected?
 303                  */
 304                 if (ctrl_reg_v & 0x18) {
 305                         ctrl_reg_v &= ~0x18;   /* reset block protect bits  */
 306                         ctrl_reg_v |=  0x02;   /* set write enable latch    */
 307                         ctrl_reg_v &= ~0x04;   /* clear RWEL                */
 308
 309                         /* Set write enable latch.
 310                          */
 311                         contr_reg[0] = 0x02;
 312                         if (i2c_write (contr_r_addr[0], 0xff, 1, contr_reg, 1) != 0) {
 313                                 rcode = 1;
 314                         }
 315
 316                         /* Set register write enable latch.
 317                          */
 318                         contr_reg[0] = 0x06;
 319                         if (i2c_write (contr_r_addr[0], 0xFF, 1, contr_reg, 1) != 0) {
 320                                 rcode = 1;
 321                         }
 322
 323                         /* Modify ctrl register.
 324                          */
 325                         contr_reg[0] = ctrl_reg_v;
 326                         if (i2c_write (contr_r_addr[0], 0xFF, 1, contr_reg, 1) != 0) {
 327                                 rcode = 1;
 328                         }
 329
 330                         /* The write (above) is an operation on NV memory.
 331                          * These can take some time (~5ms), and the device
 332                          * will not respond to further I2C messages till
 333                          * it's completed the write.
 334                          * So poll device for an I2C acknowledge.
 335                          * When we get one we know we can continue with other
 336                          * operations.
 337                          */
 338                         contr_reg[0] = 0;
 339                         for (i = 0; i < MAX_ACKNOWLEDGE_POLLS; i++) {
 340                                 if (i2c_read (addr_void[0], addr_void[1], 1, contr_reg, 1) == 0)
 341                                         break;  /* got ack */
 342 #if defined(CFG_EEPROM_PAGE_WRITE_DELAY_MS)
 343                                 udelay(CFG_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
 344 #endif
 345                         }
 346                         if (i == MAX_ACKNOWLEDGE_POLLS) {
 347                                 puts ("EEPROM poll acknowledge failed\n");
 348                                 rcode = 1;
 349                         }
 350                 }
 351
 352                 /* Is the write enable latch on?.
 353                  */
 354                 else if (!(ctrl_reg_v & 0x02)) {
 355                         /* Set write enable latch.
 356                          */
 357                         contr_reg[0] = 0x02;
 358                         if (i2c_write (contr_r_addr[0], 0xFF, 1, contr_reg, 1) != 0) {
 359                                rcode = 1;
 360                         }
 361                 }
 362                 /* Write is enabled ... now write eeprom value.
 363                  */
 364 #endif
 365                 if (i2c_write (addr[0], offset, alen-1, buffer, len) != 0)
 366                         rcode = 1;
 367
 368 #endif
 369                 buffer += len;
 370                 offset += len;
 371
 372 #if defined(CFG_EEPROM_PAGE_WRITE_DELAY_MS)
 373                 udelay(CFG_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
 374 #endif
 375         }
 376 #if defined(CFG_EEPROM_WREN)
 377         eeprom_write_enable (dev_addr,0);
 378 #endif
 379         return rcode;
 380 }
 381
 382 #ifndef CONFIG_SPI
 383 int
 384 eeprom_probe (unsigned dev_addr, unsigned offset)
 385 {
 386         unsigned char chip;
 387
 388         /* Probe the chip address
 389          */
 390 #if CFG_I2C_EEPROM_ADDR_LEN == 1 && !defined(CONFIG_SPI_X)
 391         chip = offset >> 8;             /* block number */
 392 #else
 393         chip = offset >> 16;            /* block number */
 394 #endif  /* CFG_I2C_EEPROM_ADDR_LEN, CONFIG_SPI_X */
 395
 396         chip |= dev_addr;               /* insert device address */
 397
 398         return (i2c_probe (chip));
 399 }
 400 #endif
 401
 402 /*-----------------------------------------------------------------------
 403  * Set default values
 404  */
 405 #ifndef CFG_I2C_SPEED
 406 #define CFG_I2C_SPEED   50000
 407 #endif
 408
 409 #ifndef CFG_I2C_SLAVE
 410 #define CFG_I2C_SLAVE   0xFE
 411 #endif
 412
 413 void eeprom_init  (void)
 414 {
 415 #if defined(CONFIG_SPI)
 416         spi_init_f ();
 417 #endif
 418 #if defined(CONFIG_HARD_I2C) || \
 419     defined(CONFIG_SOFT_I2C)
 420         i2c_init (CFG_I2C_SPEED, CFG_I2C_SLAVE);
 421 #endif
 422 }
 423 /*-----------------------------------------------------------------------
 424  */
 425 #endif
 426
 427 /***************************************************/
 428
 429 #if defined(CONFIG_CMD_EEPROM)
 430
 431 #ifdef CFG_I2C_MULTI_EEPROMS
 432 U_BOOT_CMD(
 433         eeprom, 6,      1,      do_eeprom,
 434         "eeprom  - EEPROM sub-system\n",
 435         "read  devaddr addr off cnt\n"
 436         "eeprom write devaddr addr off cnt\n"
 437         "       - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'\n"
 438 );
 439 #else /* One EEPROM */
 440 U_BOOT_CMD(
 441         eeprom, 5,      1,      do_eeprom,
 442         "eeprom  - EEPROM sub-system\n",
 443         "read  addr off cnt\n"
 444         "eeprom write addr off cnt\n"
 445         "       - read/write `cnt' bytes at EEPROM offset `off'\n"
 446 );
 447 #endif /* CFG_I2C_MULTI_EEPROMS */
 448
 449 #endif