git.sur5r.net Git - u-boot/blob - board/sbc8240/flash.c

   1 /*
   2  * (C) Copyright 2000-2004
   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  * Modified 4/5/2001
  26  * Wait for completion of each sector erase command issued
  27  * 4/5/2001
  28  * Chris Hallinan - DS4.COM, Inc. - clh@net1plus.com
  29  */
  30
  31 #include <common.h>
  32 #include <mpc824x.h>
  33 #include <asm/processor.h>
  34
  35 #if CONFIG_SYS_MAX_FLASH_BANKS != 1
  36 #error "CONFIG_SYS_MAX_FLASH_BANKS must be 1"
  37 #endif
  38 flash_info_t flash_info[CONFIG_SYS_MAX_FLASH_BANKS];    /* info for FLASH chips        */
  39
  40 /*-----------------------------------------------------------------------
  41  * Functions
  42  */
  43 static ulong flash_get_size (vu_long * addr, flash_info_t * info);
  44 static int write_word (flash_info_t * info, ulong dest, ulong data);
  45 static void flash_get_offsets (ulong base, flash_info_t * info);
  46
  47 #define ADDR0           0x5555
  48 #define ADDR1           0x2aaa
  49 #define FLASH_WORD_SIZE unsigned char
  50
  51 /*-----------------------------------------------------------------------
  52  */
  53
  54 unsigned long flash_init (void)
  55 {
  56         unsigned long size_b0;
  57
  58         /* Init: no FLASHes known */
  59         flash_info[0].flash_id = FLASH_UNKNOWN;
  60
  61         /* Static FLASH Bank configuration here - FIXME XXX */
  62
  63         size_b0 = flash_get_size ((vu_long *) FLASH_BASE0_PRELIM, &flash_info[0]);
  64
  65         if (flash_info[0].flash_id == FLASH_UNKNOWN) {
  66                 printf ("## Unknown FLASH on Bank 0 - Size = 0x%08lx = %ld MB\n",
  67                         size_b0, size_b0 << 20);
  68         }
  69
  70         /* Only one bank */
  71         /* Setup offsets */
  72         flash_get_offsets (FLASH_BASE0_PRELIM, &flash_info[0]);
  73
  74         /* Monitor protection ON by default */
  75         (void) flash_protect (FLAG_PROTECT_SET,
  76                               FLASH_BASE0_PRELIM,
  77                               FLASH_BASE0_PRELIM + monitor_flash_len - 1,
  78                               &flash_info[0]);
  79         flash_info[0].size = size_b0;
  80
  81         return size_b0;
  82 }
  83
  84
  85 /*-----------------------------------------------------------------------
  86  */
  87 static void flash_get_offsets (ulong base, flash_info_t * info)
  88 {
  89         int i;
  90
  91         /* set up sector start address table */
  92         if (((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST) ||
  93             (info->flash_id == FLASH_AM040)) {
  94                 for (i = 0; i < info->sector_count; i++)
  95                         info->start[i] = base + (i * 0x00010000);
  96         } else {
  97                 if (info->flash_id & FLASH_BTYPE) {
  98                         /* set sector offsets for bottom boot block type        */
  99                         info->start[0] = base + 0x00000000;
 100                         info->start[1] = base + 0x00004000;
 101                         info->start[2] = base + 0x00006000;
 102                         info->start[3] = base + 0x00008000;
 103                         for (i = 4; i < info->sector_count; i++) {
 104                                 info->start[i] =
 105                                         base + (i * 0x00010000) - 0x00030000;
 106                         }
 107                 } else {
 108                         /* set sector offsets for top boot block type           */
 109                         i = info->sector_count - 1;
 110                         info->start[i--] = base + info->size - 0x00004000;
 111                         info->start[i--] = base + info->size - 0x00006000;
 112                         info->start[i--] = base + info->size - 0x00008000;
 113                         for (; i >= 0; i--) {
 114                                 info->start[i] = base + i * 0x00010000;
 115                         }
 116                 }
 117         }
 118 }
 119
 120 /*-----------------------------------------------------------------------
 121  */
 122 void flash_print_info (flash_info_t * info)
 123 {
 124         int i;
 125         int k;
 126         int size;
 127         int erased;
 128         volatile unsigned long *flash;
 129
 130         if (info->flash_id == FLASH_UNKNOWN) {
 131                 printf ("missing or unknown FLASH type\n");
 132                 return;
 133         }
 134
 135         switch (info->flash_id & FLASH_VENDMASK) {
 136         case FLASH_MAN_AMD:
 137                 printf ("AMD ");
 138                 break;
 139         case FLASH_MAN_FUJ:
 140                 printf ("FUJITSU ");
 141                 break;
 142         case FLASH_MAN_SST:
 143                 printf ("SST ");
 144                 break;
 145         default:
 146                 printf ("Unknown Vendor ");
 147                 break;
 148         }
 149
 150         switch (info->flash_id & FLASH_TYPEMASK) {
 151         case FLASH_AM040:
 152                 printf ("AM29F040 (512 Kbit, uniform sector size)\n");
 153                 break;
 154         case FLASH_AM400B:
 155                 printf ("AM29LV400B (4 Mbit, bottom boot sect)\n");
 156                 break;
 157         case FLASH_AM400T:
 158                 printf ("AM29LV400T (4 Mbit, top boot sector)\n");
 159                 break;
 160         case FLASH_AM800B:
 161                 printf ("AM29LV800B (8 Mbit, bottom boot sect)\n");
 162                 break;
 163         case FLASH_AM800T:
 164                 printf ("AM29LV800T (8 Mbit, top boot sector)\n");
 165                 break;
 166         case FLASH_AM160B:
 167                 printf ("AM29LV160B (16 Mbit, bottom boot sect)\n");
 168                 break;
 169         case FLASH_AM160T:
 170                 printf ("AM29LV160T (16 Mbit, top boot sector)\n");
 171                 break;
 172         case FLASH_AM320B:
 173                 printf ("AM29LV320B (32 Mbit, bottom boot sect)\n");
 174                 break;
 175         case FLASH_AM320T:
 176                 printf ("AM29LV320T (32 Mbit, top boot sector)\n");
 177                 break;
 178         case FLASH_SST800A:
 179                 printf ("SST39LF/VF800 (8 Mbit, uniform sector size)\n");
 180                 break;
 181         case FLASH_SST160A:
 182                 printf ("SST39LF/VF160 (16 Mbit, uniform sector size)\n");
 183                 break;
 184         default:
 185                 printf ("Unknown Chip Type\n");
 186                 break;
 187         }
 188
 189         printf ("  Size: %ld KB in %d Sectors\n",
 190                 info->size >> 10, info->sector_count);
 191
 192         printf ("  Sector Start Addresses:");
 193         for (i = 0; i < info->sector_count; ++i) {
 194                 /*
 195                  * Check if whole sector is erased
 196                  */
 197                 if (i != (info->sector_count - 1))
 198                         size = info->start[i + 1] - info->start[i];
 199                 else
 200                         size = info->start[0] + info->size - info->start[i];
 201                 erased = 1;
 202                 flash = (volatile unsigned long *) info->start[i];
 203                 size = size >> 2;       /* divide by 4 for longword access */
 204                 for (k = 0; k < size; k++) {
 205                         if (*flash++ != 0xffffffff) {
 206                                 erased = 0;
 207                                 break;
 208                         }
 209                 }
 210
 211                 if ((i % 5) == 0)
 212                         printf ("\n   ");
 213                 printf (" %08lX%s%s",
 214                         info->start[i],
 215                         erased ? " E" : "  ", info->protect[i] ? "RO " : "   "
 216                 );
 217         }
 218         printf ("\n");
 219         return;
 220 }
 221
 222 /*-----------------------------------------------------------------------
 223  */
 224
 225
 226 /*-----------------------------------------------------------------------
 227  */
 228
 229 /*
 230  * The following code cannot be run from FLASH!
 231  */
 232 static ulong flash_get_size (vu_long * addr, flash_info_t * info)
 233 {
 234         short i;
 235         FLASH_WORD_SIZE value;
 236         ulong base = (ulong) addr;
 237         volatile FLASH_WORD_SIZE *addr2 = (FLASH_WORD_SIZE *) addr;
 238
 239         /* Write auto select command: read Manufacturer ID */
 240         addr2[ADDR0] = (FLASH_WORD_SIZE) 0x00AA00AA;
 241         addr2[ADDR1] = (FLASH_WORD_SIZE) 0x00550055;
 242         addr2[ADDR0] = (FLASH_WORD_SIZE) 0x00900090;
 243
 244         value = addr2[0];
 245
 246         switch (value) {
 247         case (FLASH_WORD_SIZE) AMD_MANUFACT:
 248                 info->flash_id = FLASH_MAN_AMD;
 249                 break;
 250         case (FLASH_WORD_SIZE) FUJ_MANUFACT:
 251                 info->flash_id = FLASH_MAN_FUJ;
 252                 break;
 253         case (FLASH_WORD_SIZE) SST_MANUFACT:
 254                 info->flash_id = FLASH_MAN_SST;
 255                 break;
 256         default:
 257                 info->flash_id = FLASH_UNKNOWN;
 258                 info->sector_count = 0;
 259                 info->size = 0;
 260                 return (0);     /* no or unknown flash  */
 261         }
 262
 263         value = addr2[1];       /* device ID            */
 264
 265         switch (value) {
 266         case (FLASH_WORD_SIZE) AMD_ID_F040B:
 267                 info->flash_id += FLASH_AM040;
 268                 info->sector_count = 8;
 269                 info->size = 0x0080000; /* => 512 ko */
 270                 break;
 271         case (FLASH_WORD_SIZE) AMD_ID_LV040B:
 272                 info->flash_id += FLASH_AM040;
 273                 info->sector_count = 8;
 274                 info->size = 0x0080000; /* => 512 ko */
 275                 break;
 276         case (FLASH_WORD_SIZE) AMD_ID_LV400T:
 277                 info->flash_id += FLASH_AM400T;
 278                 info->sector_count = 11;
 279                 info->size = 0x00080000;
 280                 break;          /* => 0.5 MB            */
 281
 282         case (FLASH_WORD_SIZE) AMD_ID_LV400B:
 283                 info->flash_id += FLASH_AM400B;
 284                 info->sector_count = 11;
 285                 info->size = 0x00080000;
 286                 break;          /* => 0.5 MB            */
 287
 288         case (FLASH_WORD_SIZE) AMD_ID_LV800T:
 289                 info->flash_id += FLASH_AM800T;
 290                 info->sector_count = 19;
 291                 info->size = 0x00100000;
 292                 break;          /* => 1 MB              */
 293
 294         case (FLASH_WORD_SIZE) AMD_ID_LV800B:
 295                 info->flash_id += FLASH_AM800B;
 296                 info->sector_count = 19;
 297                 info->size = 0x00100000;
 298                 break;          /* => 1 MB              */
 299
 300         case (FLASH_WORD_SIZE) AMD_ID_LV160T:
 301                 info->flash_id += FLASH_AM160T;
 302                 info->sector_count = 35;
 303                 info->size = 0x00200000;
 304                 break;          /* => 2 MB              */
 305
 306         case (FLASH_WORD_SIZE) AMD_ID_LV160B:
 307                 info->flash_id += FLASH_AM160B;
 308                 info->sector_count = 35;
 309                 info->size = 0x00200000;
 310                 break;          /* => 2 MB              */
 311 #if 0                           /* enable when device IDs are available */
 312         case (FLASH_WORD_SIZE) AMD_ID_LV320T:
 313                 info->flash_id += FLASH_AM320T;
 314                 info->sector_count = 67;
 315                 info->size = 0x00400000;
 316                 break;          /* => 4 MB              */
 317
 318         case (FLASH_WORD_SIZE) AMD_ID_LV320B:
 319                 info->flash_id += FLASH_AM320B;
 320                 info->sector_count = 67;
 321                 info->size = 0x00400000;
 322                 break;          /* => 4 MB              */
 323 #endif
 324         case (FLASH_WORD_SIZE) SST_ID_xF800A:
 325                 info->flash_id += FLASH_SST800A;
 326                 info->sector_count = 16;
 327                 info->size = 0x00100000;
 328                 break;          /* => 1 MB              */
 329
 330         case (FLASH_WORD_SIZE) SST_ID_xF160A:
 331                 info->flash_id += FLASH_SST160A;
 332                 info->sector_count = 32;
 333                 info->size = 0x00200000;
 334                 break;          /* => 2 MB              */
 335
 336         default:
 337                 info->flash_id = FLASH_UNKNOWN;
 338                 return (0);     /* => no or unknown flash */
 339
 340         }
 341
 342         /* set up sector start address table */
 343         if (((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST) ||
 344             (info->flash_id == FLASH_AM040)) {
 345                 for (i = 0; i < info->sector_count; i++)
 346                         info->start[i] = base + (i * 0x00010000);
 347         } else {
 348                 if (info->flash_id & FLASH_BTYPE) {
 349                         /* set sector offsets for bottom boot block type        */
 350                         info->start[0] = base + 0x00000000;
 351                         info->start[1] = base + 0x00004000;
 352                         info->start[2] = base + 0x00006000;
 353                         info->start[3] = base + 0x00008000;
 354                         for (i = 4; i < info->sector_count; i++) {
 355                                 info->start[i] =
 356                                         base + (i * 0x00010000) - 0x00030000;
 357                         }
 358                 } else {
 359                         /* set sector offsets for top boot block type           */
 360                         i = info->sector_count - 1;
 361                         info->start[i--] = base + info->size - 0x00004000;
 362                         info->start[i--] = base + info->size - 0x00006000;
 363                         info->start[i--] = base + info->size - 0x00008000;
 364                         for (; i >= 0; i--) {
 365                                 info->start[i] = base + i * 0x00010000;
 366                         }
 367                 }
 368         }
 369
 370         /* check for protected sectors */
 371         for (i = 0; i < info->sector_count; i++) {
 372                 /* read sector protection at sector address, (A7 .. A0) = 0x02 */
 373                 /* D0 = 1 if protected */
 374                 addr2 = (volatile FLASH_WORD_SIZE *) (info->start[i]);
 375                 if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_SST)
 376                         info->protect[i] = 0;
 377                 else
 378                         info->protect[i] = addr2[2] & 1;
 379         }
 380
 381         /*
 382          * Prevent writes to uninitialized FLASH.
 383          */
 384         if (info->flash_id != FLASH_UNKNOWN) {
 385                 addr2 = (FLASH_WORD_SIZE *) info->start[0];
 386                 *addr2 = (FLASH_WORD_SIZE) 0x00F000F0;  /* reset bank */
 387         }
 388
 389         return (info->size);
 390 }
 391
 392 int wait_for_DQ7 (flash_info_t * info, int sect)
 393 {
 394         ulong start, now, last;
 395         volatile FLASH_WORD_SIZE *addr =
 396                 (FLASH_WORD_SIZE *) (info->start[sect]);
 397
 398         start = get_timer (0);
 399         last = start;
 400         while ((addr[0] & (FLASH_WORD_SIZE) 0x00800080) !=
 401                (FLASH_WORD_SIZE) 0x00800080) {
 402                 if ((now = get_timer (start)) > CONFIG_SYS_FLASH_ERASE_TOUT) {
 403                         printf ("Timeout\n");
 404                         return -1;
 405                 }
 406                 /* show that we're waiting */
 407                 if ((now - last) > 1000) {      /* every second */
 408                         putc ('.');
 409                         last = now;
 410                 }
 411         }
 412         return 0;
 413 }
 414
 415 /*-----------------------------------------------------------------------
 416  */
 417
 418 int flash_erase (flash_info_t * info, int s_first, int s_last)
 419 {
 420         volatile FLASH_WORD_SIZE *addr = (FLASH_WORD_SIZE *) (info->start[0]);
 421         volatile FLASH_WORD_SIZE *addr2;
 422         int flag, prot, sect, l_sect;
 423         int i;
 424
 425         if ((s_first < 0) || (s_first > s_last)) {
 426                 if (info->flash_id == FLASH_UNKNOWN) {
 427                         printf ("- missing\n");
 428                 } else {
 429                         printf ("- no sectors to erase\n");
 430                 }
 431                 return 1;
 432         }
 433
 434         if (info->flash_id == FLASH_UNKNOWN) {
 435                 printf ("Can't erase unknown flash type - aborted\n");
 436                 return 1;
 437         }
 438
 439         prot = 0;
 440         for (sect = s_first; sect <= s_last; ++sect) {
 441                 if (info->protect[sect]) {
 442                         prot++;
 443                 }
 444         }
 445
 446         if (prot) {
 447                 printf ("- Warning: %d protected sectors will not be erased!\n", prot);
 448         } else {
 449                 printf ("\n");
 450         }
 451
 452         l_sect = -1;
 453
 454         /* Disable interrupts which might cause a timeout here */
 455         flag = disable_interrupts ();
 456
 457         /* Start erase on unprotected sectors */
 458         for (sect = s_first; sect <= s_last; sect++) {
 459                 if (info->protect[sect] == 0) { /* not protected */
 460                         addr2 = (FLASH_WORD_SIZE *) (info->start[sect]);
 461                         printf ("Erasing sector %p\n", addr2);  /* CLH */
 462
 463                         if ((info->flash_id & FLASH_VENDMASK) ==
 464                             FLASH_MAN_SST) {
 465                                 addr[ADDR0] = (FLASH_WORD_SIZE) 0x00AA00AA;
 466                                 addr[ADDR1] = (FLASH_WORD_SIZE) 0x00550055;
 467                                 addr[ADDR0] = (FLASH_WORD_SIZE) 0x00800080;
 468                                 addr[ADDR0] = (FLASH_WORD_SIZE) 0x00AA00AA;
 469                                 addr[ADDR1] = (FLASH_WORD_SIZE) 0x00550055;
 470                                 addr2[0] = (FLASH_WORD_SIZE) 0x00500050;        /* block erase */
 471                                 for (i = 0; i < 50; i++)
 472                                         udelay (1000);  /* wait 1 ms */
 473                         } else {
 474                                 addr[ADDR0] = (FLASH_WORD_SIZE) 0x00AA00AA;
 475                                 addr[ADDR1] = (FLASH_WORD_SIZE) 0x00550055;
 476                                 addr[ADDR0] = (FLASH_WORD_SIZE) 0x00800080;
 477                                 addr[ADDR0] = (FLASH_WORD_SIZE) 0x00AA00AA;
 478                                 addr[ADDR1] = (FLASH_WORD_SIZE) 0x00550055;
 479                                 addr2[0] = (FLASH_WORD_SIZE) 0x00300030;        /* sector erase */
 480                         }
 481                         l_sect = sect;
 482                         /*
 483                          * Wait for each sector to complete, it's more
 484                          * reliable.  According to AMD Spec, you must
 485                          * issue all erase commands within a specified
 486                          * timeout.  This has been seen to fail, especially
 487                          * if printf()s are included (for debug)!!
 488                          */
 489                         wait_for_DQ7 (info, sect);
 490                 }
 491         }
 492
 493         /* re-enable interrupts if necessary */
 494         if (flag)
 495                 enable_interrupts ();
 496
 497         /* wait at least 80us - let's wait 1 ms */
 498         udelay (1000);
 499
 500 #if 0
 501         /*
 502          * We wait for the last triggered sector
 503          */
 504         if (l_sect < 0)
 505                 goto DONE;
 506         wait_for_DQ7 (info, l_sect);
 507
 508       DONE:
 509 #endif
 510         /* reset to read mode */
 511         addr = (FLASH_WORD_SIZE *) info->start[0];
 512         addr[0] = (FLASH_WORD_SIZE) 0x00F000F0; /* reset bank */
 513
 514         printf (" done\n");
 515         return 0;
 516 }
 517
 518 /*-----------------------------------------------------------------------
 519  * Copy memory to flash, returns:
 520  * 0 - OK
 521  * 1 - write timeout
 522  * 2 - Flash not erased
 523  */
 524
 525 int write_buff (flash_info_t * info, uchar * src, ulong addr, ulong cnt)
 526 {
 527         ulong cp, wp, data;
 528         int i, l, rc;
 529
 530         wp = (addr & ~3);       /* get lower word aligned address */
 531
 532         /*
 533          * handle unaligned start bytes
 534          */
 535         if ((l = addr - wp) != 0) {
 536                 data = 0;
 537                 for (i = 0, cp = wp; i < l; ++i, ++cp) {
 538                         data = (data << 8) | (*(uchar *) cp);
 539                 }
 540                 for (; i < 4 && cnt > 0; ++i) {
 541                         data = (data << 8) | *src++;
 542                         --cnt;
 543                         ++cp;
 544                 }
 545                 for (; cnt == 0 && i < 4; ++i, ++cp) {
 546                         data = (data << 8) | (*(uchar *) cp);
 547                 }
 548
 549                 if ((rc = write_word (info, wp, data)) != 0) {
 550                         return (rc);
 551                 }
 552                 wp += 4;
 553         }
 554
 555         /*
 556          * handle word aligned part
 557          */
 558         while (cnt >= 4) {
 559                 data = 0;
 560                 for (i = 0; i < 4; ++i) {
 561                         data = (data << 8) | *src++;
 562                 }
 563                 if ((rc = write_word (info, wp, data)) != 0) {
 564                         return (rc);
 565                 }
 566                 wp += 4;
 567                 cnt -= 4;
 568         }
 569
 570         if (cnt == 0) {
 571                 return (0);
 572         }
 573
 574         /*
 575          * handle unaligned tail bytes
 576          */
 577         data = 0;
 578         for (i = 0, cp = wp; i < 4 && cnt > 0; ++i, ++cp) {
 579                 data = (data << 8) | *src++;
 580                 --cnt;
 581         }
 582         for (; i < 4; ++i, ++cp) {
 583                 data = (data << 8) | (*(uchar *) cp);
 584         }
 585
 586         return (write_word (info, wp, data));
 587 }
 588
 589 /*-----------------------------------------------------------------------
 590  * Write a word to Flash, returns:
 591  * 0 - OK
 592  * 1 - write timeout
 593  * 2 - Flash not erased
 594  */
 595 static int write_word (flash_info_t * info, ulong dest, ulong data)
 596 {
 597         volatile FLASH_WORD_SIZE *addr2 =
 598                 (FLASH_WORD_SIZE *) (info->start[0]);
 599         volatile FLASH_WORD_SIZE *dest2 = (FLASH_WORD_SIZE *) dest;
 600         volatile FLASH_WORD_SIZE *data2 = (FLASH_WORD_SIZE *) & data;
 601         ulong start;
 602         int i;
 603
 604         /* Check if Flash is (sufficiently) erased */
 605         if ((*((volatile FLASH_WORD_SIZE *) dest) &
 606              (FLASH_WORD_SIZE) data) != (FLASH_WORD_SIZE) data) {
 607                 return (2);
 608         }
 609
 610         for (i = 0; i < 4 / sizeof (FLASH_WORD_SIZE); i++) {
 611                 int flag;
 612
 613                 /* Disable interrupts which might cause a timeout here */
 614                 flag = disable_interrupts ();
 615
 616                 addr2[ADDR0] = (FLASH_WORD_SIZE) 0x00AA00AA;
 617                 addr2[ADDR1] = (FLASH_WORD_SIZE) 0x00550055;
 618                 addr2[ADDR0] = (FLASH_WORD_SIZE) 0x00A000A0;
 619
 620                 dest2[i] = data2[i];
 621
 622                 /* re-enable interrupts if necessary */
 623                 if (flag)
 624                         enable_interrupts ();
 625
 626                 /* data polling for D7 */
 627                 start = get_timer (0);
 628                 while ((dest2[i] & (FLASH_WORD_SIZE) 0x00800080) !=
 629                        (data2[i] & (FLASH_WORD_SIZE) 0x00800080)) {
 630
 631                         if (get_timer (start) > CONFIG_SYS_FLASH_WRITE_TOUT) {
 632                                 return (1);
 633                         }
 634                 }
 635         }
 636
 637         return (0);
 638 }