board/etx094/flash.c

   1 /*
   2  * (C) Copyright 2000
   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 #include <common.h>
  25 #include <mpc8xx.h>
  26
  27 flash_info_t    flash_info[CONFIG_SYS_MAX_FLASH_BANKS];
  28
  29 /*-----------------------------------------------------------------------
  30  * Functions
  31  */
  32 static ulong flash_get_size(vu_long *addr, flash_info_t *info);
  33 static int write_word(flash_info_t *info, ulong dest, ulong data);
  34 static void flash_get_offsets(ulong base, flash_info_t *info);
  35
  36 /*-----------------------------------------------------------------------
  37  */
  38
  39 unsigned long flash_init(void)
  40 {
  41         volatile immap_t     *immap  = (immap_t *)CONFIG_SYS_IMMR;
  42         volatile memctl8xx_t *memctl = &immap->im_memctl;
  43         unsigned long size_b0, size_b1;
  44         int i;
  45
  46         /* Init: no FLASHes known */
  47         for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; ++i)
  48                 flash_info[i].flash_id = FLASH_UNKNOWN;
  49
  50         /* Static FLASH Bank configuration here - FIXME XXX */
  51
  52         size_b0 = flash_get_size((vu_long *)FLASH_BASE0_PRELIM, &flash_info[0]);
  53
  54         if (flash_info[0].flash_id == FLASH_UNKNOWN) {
  55                 printf("## Unknown FLASH on Bank 0 - Size = 0x%08lx = %ld MB\n",
  56                         size_b0, size_b0<<20);
  57         }
  58
  59         size_b1 = flash_get_size((vu_long *)FLASH_BASE1_PRELIM, &flash_info[1]);
  60
  61         if (size_b1 > size_b0) {
  62                 printf("## ERROR: "
  63                         "Bank 1 (0x%08lx = %ld MB) > Bank 0 (0x%08lx = %ld MB)\n",
  64                         size_b1, size_b1<<20,
  65                         size_b0, size_b0<<20
  66                 );
  67                 flash_info[0].flash_id  = FLASH_UNKNOWN;
  68                 flash_info[1].flash_id  = FLASH_UNKNOWN;
  69                 flash_info[0].sector_count      = -1;
  70                 flash_info[1].sector_count      = -1;
  71                 flash_info[0].size              = 0;
  72                 flash_info[1].size              = 0;
  73                 return 0;
  74         }
  75
  76         /* Remap FLASH according to real size */
  77         memctl->memc_or0 = CONFIG_SYS_OR_TIMING_FLASH | (-size_b0 & 0xFFFF8000);
  78 #ifdef CONFIG_FLASH_16BIT
  79         memctl->memc_br0 = (CONFIG_SYS_FLASH_BASE & BR_BA_MSK) |
  80                 BR_MS_GPCM | BR_V | BR_PS_16; /* 16 Bit data port */
  81 #else
  82         memctl->memc_br0 = (CONFIG_SYS_FLASH_BASE & BR_BA_MSK) |
  83                 BR_MS_GPCM | BR_V;
  84 #endif
  85
  86         /* Re-do sizing to get full correct info */
  87         size_b0 = flash_get_size((vu_long *)CONFIG_SYS_FLASH_BASE,
  88                         &flash_info[0]);
  89
  90         flash_get_offsets(CONFIG_SYS_FLASH_BASE, &flash_info[0]);
  91
  92 #if CONFIG_SYS_MONITOR_BASE >= CONFIG_SYS_FLASH_BASE
  93         /* monitor protection ON by default */
  94         flash_protect(FLAG_PROTECT_SET,
  95                       CONFIG_SYS_MONITOR_BASE,
  96                       CONFIG_SYS_MONITOR_BASE+monitor_flash_len-1,
  97                       &flash_info[0]);
  98 #endif
  99
 100         if (size_b1) {
 101                 memctl->memc_or1 = CONFIG_SYS_OR_TIMING_FLASH |
 102                         (-size_b1 & 0xFFFF8000);
 103 #ifdef CONFIG_FLASH_16BIT
 104                 memctl->memc_br1 = ((CONFIG_SYS_FLASH_BASE + size_b0) &
 105                         BR_BA_MSK) | BR_MS_GPCM | BR_V | BR_PS_16;
 106 #else
 107                 memctl->memc_br1 = ((CONFIG_SYS_FLASH_BASE + size_b0) &
 108                         BR_BA_MSK) | BR_MS_GPCM | BR_V;
 109 #endif
 110
 111                 /* Re-do sizing to get full correct info */
 112                 size_b1 = flash_get_size((vu_long *)(CONFIG_SYS_FLASH_BASE +
 113                                 size_b0), &flash_info[1]);
 114
 115                 flash_get_offsets(CONFIG_SYS_FLASH_BASE + size_b0,
 116                                 &flash_info[1]);
 117
 118 #if CONFIG_SYS_MONITOR_BASE >= CONFIG_SYS_FLASH_BASE
 119                 /* monitor protection ON by default */
 120                 flash_protect(FLAG_PROTECT_SET,
 121                               CONFIG_SYS_MONITOR_BASE,
 122                               CONFIG_SYS_MONITOR_BASE+monitor_flash_len-1,
 123                               &flash_info[1]);
 124 #endif
 125         } else {
 126                 memctl->memc_br1 = 0;           /* invalidate bank */
 127
 128                 flash_info[1].flash_id = FLASH_UNKNOWN;
 129                 flash_info[1].sector_count = -1;
 130         }
 131
 132         flash_info[0].size = size_b0;
 133         flash_info[1].size = size_b1;
 134
 135         return size_b0 + size_b1;
 136 }
 137
 138 /*-----------------------------------------------------------------------
 139  */
 140 static void flash_get_offsets(ulong base, flash_info_t *info)
 141 {
 142         int i;
 143
 144         if (info->flash_id == FLASH_UNKNOWN)
 145                 return;
 146
 147         if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST) {
 148                 for (i = 0; i < info->sector_count; i++)
 149                         info->start[i] = base + (i * 0x00002000);
 150
 151                 return;
 152         }
 153
 154         /* set up sector start address table */
 155         if (info->flash_id & FLASH_BTYPE) {
 156                 /* set sector offsets for bottom boot block type        */
 157 #ifdef CONFIG_FLASH_16BIT
 158                 info->start[0] = base + 0x00000000;
 159                 info->start[1] = base + 0x00004000;
 160                 info->start[2] = base + 0x00006000;
 161                 info->start[3] = base + 0x00008000;
 162                 for (i = 4; i < info->sector_count; i++)
 163                         info->start[i] = base + (i * 0x00010000) - 0x00030000;
 164 #else
 165                 info->start[0] = base + 0x00000000;
 166                 info->start[1] = base + 0x00008000;
 167                 info->start[2] = base + 0x0000C000;
 168                 info->start[3] = base + 0x00010000;
 169                 for (i = 4; i < info->sector_count; i++)
 170                         info->start[i] = base + (i * 0x00020000) - 0x00060000;
 171 #endif
 172         } else {
 173                 /* set sector offsets for top boot block type           */
 174                 i = info->sector_count - 1;
 175                 info->start[i--] = base + info->size - 0x00008000;
 176                 info->start[i--] = base + info->size - 0x0000C000;
 177                 info->start[i--] = base + info->size - 0x00010000;
 178                 for (; i >= 0; i--)
 179                         info->start[i] = base + i * 0x00020000;
 180         }
 181 }
 182
 183 /*-----------------------------------------------------------------------
 184  */
 185 void flash_print_info(flash_info_t *info)
 186 {
 187         int i;
 188
 189         if (info->flash_id == FLASH_UNKNOWN) {
 190                 printf("missing or unknown FLASH type\n");
 191                 return;
 192         }
 193
 194         switch (info->flash_id & FLASH_VENDMASK) {
 195         case FLASH_MAN_AMD:
 196                 printf("AMD ");
 197                 break;
 198         case FLASH_MAN_FUJ:
 199                 printf("FUJITSU ");
 200                 break;
 201         case FLASH_MAN_SST:
 202                 printf("SST ");
 203                 break;
 204         case FLASH_MAN_STM:
 205                 printf("STM ");
 206                 break;
 207         default:
 208                 printf("Unknown Vendor ");
 209                 break;
 210         }
 211
 212         switch (info->flash_id & FLASH_TYPEMASK) {
 213         case FLASH_AM400B:
 214                 printf("AM29LV400B (4 Mbit, bottom boot sect)\n");
 215                 break;
 216         case FLASH_AM400T:
 217                 printf("AM29LV400T (4 Mbit, top boot sector)\n");
 218                 break;
 219         case FLASH_AM800B:
 220                 printf("AM29LV800B (8 Mbit, bottom boot sect)\n");
 221                 break;
 222         case FLASH_AM800T:
 223                 printf("AM29LV800T (8 Mbit, top boot sector)\n");
 224                 break;
 225         case FLASH_AM160B:
 226                 printf("AM29LV160B (16 Mbit, bottom boot sect)\n");
 227                 break;
 228         case FLASH_AM160T:
 229                 printf("AM29LV160T (16 Mbit, top boot sector)\n");
 230                 break;
 231         case FLASH_AM320B:
 232                 printf("AM29LV320B (32 Mbit, bottom boot sect)\n");
 233                 break;
 234         case FLASH_AM320T:
 235                 printf("AM29LV320T (32 Mbit, top boot sector)\n");
 236                 break;
 237         case FLASH_SST200A:
 238                 printf("39xF200A (2M = 128K x 16)\n");
 239                 break;
 240         case FLASH_SST400A:
 241                 printf("39xF400A (4M = 256K x 16)\n");
 242                 break;
 243         case FLASH_SST800A:
 244                 printf("39xF800A (8M = 512K x 16)\n");
 245                 break;
 246         case FLASH_STM800AB:
 247                 printf("M29W800AB (8M = 512K x 16)\n");
 248                 break;
 249         default:
 250                 printf("Unknown Chip Type\n");
 251                 break;
 252         }
 253
 254         printf("  Size: %ld MB in %d Sectors\n",
 255                 info->size >> 20, info->sector_count);
 256
 257         printf("  Sector Start Addresses:");
 258         for (i = 0; i < info->sector_count; ++i) {
 259                 if ((i % 5) == 0)
 260                         printf("\n   ");
 261                 printf(" %08lX%s",
 262                         info->start[i],
 263                         info->protect[i] ? " (RO)" : "     "
 264                 );
 265         }
 266         printf("\n");
 267         return;
 268 }
 269
 270 /*
 271  * The following code cannot be run from FLASH!
 272  */
 273
 274 static ulong flash_get_size(vu_long *addr, flash_info_t *info)
 275 {
 276         short i;
 277         ulong value;
 278         ulong base = (ulong)addr;
 279
 280         /* Write auto select command: read Manufacturer ID */
 281 #ifdef CONFIG_FLASH_16BIT
 282         vu_short *s_addr = (vu_short *)addr;
 283         s_addr[0x5555] = 0x00AA;
 284         s_addr[0x2AAA] = 0x0055;
 285         s_addr[0x5555] = 0x0090;
 286         value = s_addr[0];
 287         value = value|(value<<16);
 288 #else
 289         addr[0x5555] = 0x00AA00AA;
 290         addr[0x2AAA] = 0x00550055;
 291         addr[0x5555] = 0x00900090;
 292         value = addr[0];
 293 #endif
 294
 295         switch (value) {
 296         case AMD_MANUFACT:
 297                 info->flash_id = FLASH_MAN_AMD;
 298                 break;
 299         case FUJ_MANUFACT:
 300                 info->flash_id = FLASH_MAN_FUJ;
 301                 break;
 302         case SST_MANUFACT:
 303                 info->flash_id = FLASH_MAN_SST;
 304                 break;
 305         case STM_MANUFACT:
 306                 info->flash_id = FLASH_MAN_STM;
 307                 break;
 308         default:
 309                 info->flash_id = FLASH_UNKNOWN;
 310                 info->sector_count = 0;
 311                 info->size = 0;
 312                 return 0;                       /* no or unknown flash  */
 313         }
 314 #ifdef CONFIG_FLASH_16BIT
 315         value = s_addr[1];
 316         value = value|(value<<16);
 317 #else
 318         value = addr[1];                        /* device ID            */
 319 #endif
 320
 321         switch (value) {
 322         case AMD_ID_LV400T:
 323                 info->flash_id += FLASH_AM400T;
 324                 info->sector_count = 11;
 325                 info->size = 0x00100000;
 326                 break;                          /* => 1 MB              */
 327
 328         case AMD_ID_LV400B:
 329                 info->flash_id += FLASH_AM400B;
 330                 info->sector_count = 11;
 331                 info->size = 0x00100000;
 332                 break;                          /* => 1 MB              */
 333
 334         case AMD_ID_LV800T:
 335                 info->flash_id += FLASH_AM800T;
 336                 info->sector_count = 19;
 337                 info->size = 0x00200000;
 338                 break;                          /* => 2 MB              */
 339
 340         case AMD_ID_LV800B:
 341                 info->flash_id += FLASH_AM800B;
 342 #ifdef CONFIG_FLASH_16BIT
 343                 info->sector_count = 19;
 344                 info->size = 0x00100000;        /* => 1 MB */
 345 #else
 346                 info->sector_count = 19;
 347                 info->size = 0x00200000;        /* => 2 MB      */
 348 #endif
 349                 break;
 350
 351         case AMD_ID_LV160T:
 352                 info->flash_id += FLASH_AM160T;
 353                 info->sector_count = 35;
 354                 info->size = 0x00400000;
 355                 break;                          /* => 4 MB              */
 356
 357         case AMD_ID_LV160B:
 358                 info->flash_id += FLASH_AM160B;
 359 #ifdef CONFIG_FLASH_16BIT
 360                 info->sector_count = 35;
 361                 info->size = 0x00200000;        /* => 2 MB      */
 362 #else
 363                 info->sector_count = 35;
 364                 info->size = 0x00400000;        /* => 4 MB      */
 365 #endif
 366
 367                 break;
 368         case SST_ID_xF200A:
 369                 info->flash_id += FLASH_SST200A;
 370                 info->sector_count = 64;        /* 39xF200A (2M = 128K x 16) */
 371                 info->size = 0x00080000;
 372                 break;
 373         case SST_ID_xF400A:
 374                 info->flash_id += FLASH_SST400A;
 375                 info->sector_count = 128;       /* 39xF400A (4M = 256K x 16) */
 376                 info->size = 0x00100000;
 377                 break;
 378         case SST_ID_xF800A:
 379                 info->flash_id += FLASH_SST800A;
 380                 info->sector_count = 256;       /* 39xF800A (8M = 512K x 16) */
 381                 info->size = 0x00200000;
 382                 break;                          /* => 2 MB              */
 383         case STM_ID_x800AB:
 384                 info->flash_id += FLASH_STM800AB;
 385                 info->sector_count = 19;
 386                 info->size = 0x00200000;
 387                 break;                          /* => 2 MB              */
 388         default:
 389                 info->flash_id = FLASH_UNKNOWN;
 390                 return 0;                       /* => no or unknown flash */
 391
 392         }
 393
 394         if (info->sector_count > CONFIG_SYS_MAX_FLASH_SECT) {
 395                 printf("** ERROR: sector count %d > max (%d) **\n",
 396                         info->sector_count, CONFIG_SYS_MAX_FLASH_SECT);
 397                 info->sector_count = CONFIG_SYS_MAX_FLASH_SECT;
 398         }
 399
 400         if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST) {
 401                 for (i = 0; i < info->sector_count; i++)
 402                         info->start[i] = base + (i * 0x00002000);
 403         } else {        /* AMD and Fujitsu types */
 404                 /* set up sector start address table */
 405                 if (info->flash_id & FLASH_BTYPE) {
 406                         /* set sector offsets for bottom boot block type */
 407 #ifdef CONFIG_FLASH_16BIT
 408
 409                         info->start[0] = base + 0x00000000;
 410                         info->start[1] = base + 0x00004000;
 411                         info->start[2] = base + 0x00006000;
 412                         info->start[3] = base + 0x00008000;
 413                         for (i = 4; i < info->sector_count; i++)
 414                                 info->start[i] = base +
 415                                         (i * 0x00010000) - 0x00030000;
 416 #else
 417                         info->start[0] = base + 0x00000000;
 418                         info->start[1] = base + 0x00008000;
 419                         info->start[2] = base + 0x0000C000;
 420                         info->start[3] = base + 0x00010000;
 421                         for (i = 4; i < info->sector_count; i++)
 422                                 info->start[i] = base +
 423                                         (i * 0x00020000) - 0x00060000;
 424 #endif
 425                 } else {
 426                         /* set sector offsets for top boot block type   */
 427                         i = info->sector_count - 1;
 428                         info->start[i--] = base + info->size - 0x00008000;
 429                         info->start[i--] = base + info->size - 0x0000C000;
 430                         info->start[i--] = base + info->size - 0x00010000;
 431                         for (; i >= 0; i--)
 432                                 info->start[i] = base + i * 0x00020000;
 433                 }
 434
 435                 /* check for protected sectors */
 436                 for (i = 0; i < info->sector_count; i++) {
 437                         /*
 438                          * read sector protection at sector address:
 439                          * (A7 .. A0) = 0x02
 440                          * D0 = 1 if protected
 441                          */
 442 #ifdef CONFIG_FLASH_16BIT
 443                         s_addr = (volatile unsigned short *)(info->start[i]);
 444                         info->protect[i] = s_addr[2] & 1;
 445 #else
 446                         addr = (volatile unsigned long *)(info->start[i]);
 447                         info->protect[i] = addr[2] & 1;
 448 #endif
 449                 }
 450         }
 451
 452         /*
 453          * Prevent writes to uninitialized FLASH.
 454          */
 455         if (info->flash_id != FLASH_UNKNOWN) {
 456 #ifdef CONFIG_FLASH_16BIT
 457                 s_addr = (volatile unsigned short *)(info->start[0]);
 458                 *s_addr = 0x00F0;       /* reset bank */
 459 #else
 460                 addr = (volatile unsigned long *)info->start[0];
 461                 *addr = 0x00F000F0;     /* reset bank */
 462 #endif
 463
 464         }
 465         return info->size;
 466 }
 467
 468 int     flash_erase(flash_info_t *info, int s_first, int s_last)
 469 {
 470         vu_long *addr = (vu_long *)(info->start[0]);
 471         int flag, prot, sect;
 472         ulong start, now, last;
 473 #ifdef CONFIG_FLASH_16BIT
 474         vu_short *s_addr = (vu_short *)addr;
 475 #endif
 476
 477         if ((s_first < 0) || (s_first > s_last)) {
 478                 if (info->flash_id == FLASH_UNKNOWN)
 479                         printf("- missing\n");
 480                 else
 481                         printf("- no sectors to erase\n");
 482                 return 1;
 483         }
 484 /*#ifndef CONFIG_FLASH_16BIT
 485         ulong type;
 486         type = (info->flash_id & FLASH_VENDMASK);
 487         if ((type != FLASH_MAN_SST) && (type != FLASH_MAN_STM)) {
 488                 printf ("Can't erase unknown flash type %08lx - aborted\n",
 489                         info->flash_id);
 490                 return;
 491         }
 492 #endif*/
 493         prot = 0;
 494         for (sect = s_first; sect <= s_last; ++sect) {
 495                 if (info->protect[sect])
 496                         prot++;
 497         }
 498
 499         if (prot) {
 500                 printf("- Warning: %d protected sectors will not be erased!\n",
 501                         prot);
 502         } else {
 503                 printf("\n");
 504         }
 505
 506         start = get_timer(0);
 507         last  = start;
 508         /* Start erase on unprotected sectors */
 509         for (sect = s_first; sect <= s_last; sect++) {
 510                 if (info->protect[sect] == 0) { /* not protected */
 511 #ifdef CONFIG_FLASH_16BIT
 512                         vu_short *s_sect_addr = (vu_short *)(info->start[sect]);
 513 #else
 514                         vu_long *sect_addr = (vu_long *)(info->start[sect]);
 515 #endif
 516                         /* Disable interrupts which might cause a timeout */
 517                         flag = disable_interrupts();
 518
 519 #ifdef CONFIG_FLASH_16BIT
 520
 521                         /*printf("\ns_sect_addr=%x",s_sect_addr);*/
 522                         s_addr[0x5555] = 0x00AA;
 523                         s_addr[0x2AAA] = 0x0055;
 524                         s_addr[0x5555] = 0x0080;
 525                         s_addr[0x5555] = 0x00AA;
 526                         s_addr[0x2AAA] = 0x0055;
 527                         s_sect_addr[0] = 0x0030;
 528 #else
 529                         addr[0x5555] = 0x00AA00AA;
 530                         addr[0x2AAA] = 0x00550055;
 531                         addr[0x5555] = 0x00800080;
 532                         addr[0x5555] = 0x00AA00AA;
 533                         addr[0x2AAA] = 0x00550055;
 534                         sect_addr[0] = 0x00300030;
 535 #endif
 536                         /* re-enable interrupts if necessary */
 537                         if (flag)
 538                                 enable_interrupts();
 539
 540                         /* wait at least 80us - let's wait 1 ms */
 541                         udelay(1000);
 542
 543 #ifdef CONFIG_FLASH_16BIT
 544                         while ((s_sect_addr[0] & 0x0080) != 0x0080) {
 545 #else
 546                         while ((sect_addr[0] & 0x00800080) != 0x00800080) {
 547 #endif
 548                                 now = get_timer(start);
 549                                 if (now > CONFIG_SYS_FLASH_ERASE_TOUT) {
 550                                         printf("Timeout\n");
 551                                         return 1;
 552                                 }
 553                                 /* show every second that we're waiting */
 554                                 if ((now - last) > 1000) {
 555                                         putc('.');
 556                                         last = now;
 557                                 }
 558                         }
 559                 }
 560         }
 561
 562         /* reset to read mode */
 563         addr = (volatile unsigned long *)info->start[0];
 564 #ifdef CONFIG_FLASH_16BIT
 565         s_addr[0] = 0x00F0;     /* reset bank */
 566 #else
 567         addr[0] = 0x00F000F0;   /* reset bank */
 568 #endif
 569
 570         printf(" done\n");
 571         return 0;
 572 }
 573
 574 /*-----------------------------------------------------------------------
 575  * Copy memory to flash, returns:
 576  * 0 - OK
 577  * 1 - write timeout
 578  * 2 - Flash not erased
 579  * 4 - Flash not identified
 580  */
 581
 582 int write_buff(flash_info_t *info, uchar *src, ulong addr, ulong cnt)
 583 {
 584         ulong cp, wp, data;
 585         int i, l, rc;
 586
 587         if (info->flash_id == FLASH_UNKNOWN)
 588                 return 4;
 589
 590         wp = (addr & ~3);       /* get lower word aligned address */
 591
 592         /*
 593          * handle unaligned start bytes
 594          */
 595         l = addr - wp;
 596
 597         if (l != 0) {
 598                 data = 0;
 599                 for (i = 0, cp = wp; i < l; ++i, ++cp)
 600                         data = (data << 8) | (*(uchar *)cp);
 601
 602                 for (; i < 4 && cnt > 0; ++i) {
 603                         data = (data << 8) | *src++;
 604                         --cnt;
 605                         ++cp;
 606                 }
 607                 for (; cnt == 0 && i < 4; ++i, ++cp)
 608                         data = (data << 8) | (*(uchar *)cp);
 609
 610                 rc = write_word(info, wp, data);
 611
 612                 if (rc != 0)
 613                         return rc;
 614
 615                 wp += 4;
 616         }
 617
 618         /*
 619          * handle word aligned part
 620          */
 621         while (cnt >= 4) {
 622                 data = 0;
 623                 for (i = 0; i < 4; ++i)
 624                         data = (data << 8) | *src++;
 625
 626                 rc = write_word(info, wp, data);
 627                 if (rc != 0)
 628                         return rc;
 629
 630                 wp  += 4;
 631                 cnt -= 4;
 632         }
 633
 634         if (cnt == 0)
 635                 return 0;
 636
 637         /*
 638          * handle unaligned tail bytes
 639          */
 640         data = 0;
 641         for (i = 0, cp = wp; i < 4 && cnt > 0; ++i, ++cp) {
 642                 data = (data << 8) | *src++;
 643                 --cnt;
 644         }
 645         for (; i < 4; ++i, ++cp)
 646                 data = (data << 8) | (*(uchar *)cp);
 647
 648         return write_word(info, wp, data);
 649 }
 650
 651 /*-----------------------------------------------------------------------
 652  * Write a word to Flash, returns:
 653  * 0 - OK
 654  * 1 - write timeout
 655  * 2 - Flash not erased
 656  */
 657 static int write_word(flash_info_t *info, ulong dest, ulong data)
 658 {
 659         vu_long *addr = (vu_long *)(info->start[0]);
 660
 661 #ifdef CONFIG_FLASH_16BIT
 662         vu_short high_data;
 663         vu_short low_data;
 664         vu_short *s_addr = (vu_short *)addr;
 665 #endif
 666         ulong start;
 667         int flag;
 668
 669         /* Check if Flash is (sufficiently) erased */
 670         if ((*((vu_long *)dest) & data) != data)
 671                 return 2;
 672
 673 #ifdef CONFIG_FLASH_16BIT
 674         /* Write the 16 higher-bits */
 675         /* Disable interrupts which might cause a timeout here */
 676         flag = disable_interrupts();
 677
 678         high_data = ((data>>16) & 0x0000ffff);
 679
 680         s_addr[0x5555] = 0x00AA;
 681         s_addr[0x2AAA] = 0x0055;
 682         s_addr[0x5555] = 0x00A0;
 683
 684         *((vu_short *)dest) = high_data;
 685
 686         /* re-enable interrupts if necessary */
 687         if (flag)
 688                 enable_interrupts();
 689
 690         /* data polling for D7 */
 691         start = get_timer(0);
 692         while ((*((vu_short *)dest) & 0x0080) != (high_data & 0x0080)) {
 693                 if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT)
 694                         return 1;
 695         }
 696
 697         /* Write the 16 lower-bits */
 698 #endif
 699
 700         /* Disable interrupts which might cause a timeout here */
 701         flag = disable_interrupts();
 702 #ifdef CONFIG_FLASH_16BIT
 703         dest += 0x2;
 704         low_data = (data & 0x0000ffff);
 705
 706         s_addr[0x5555] = 0x00AA;
 707         s_addr[0x2AAA] = 0x0055;
 708         s_addr[0x5555] = 0x00A0;
 709         *((vu_short *)dest) = low_data;
 710
 711 #else
 712         addr[0x5555] = 0x00AA00AA;
 713         addr[0x2AAA] = 0x00550055;
 714         addr[0x5555] = 0x00A000A0;
 715         *((vu_long *)dest) = data;
 716 #endif
 717
 718         /* re-enable interrupts if necessary */
 719         if (flag)
 720                 enable_interrupts();
 721
 722         /* data polling for D7 */
 723         start = get_timer(0);
 724
 725 #ifdef CONFIG_FLASH_16BIT
 726         while ((*((vu_short *)dest) & 0x0080) != (low_data & 0x0080)) {
 727 #else
 728         while ((*((vu_long *)dest) & 0x00800080) != (data & 0x00800080)) {
 729 #endif
 730
 731                 if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT)
 732                         return 1;
 733         }
 734         return 0;
 735 }