board/gen860t/flash.c

   1 /*
   2  * (C) Copyright 2001
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  * Keith Outwater, keith_outwater@mvsi.com
   5  *
   6  * See file CREDITS for list of people who contributed to this
   7  * project.
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License as
  11  * published by the Free Software Foundation; either version 2 of
  12  * the License, or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  22  * MA 02111-1307 USA
  23  */
  24
  25 #include <common.h>
  26 #include <mpc8xx.h>
  27
  28 #if defined(CONFIG_ENV_IS_IN_FLASH)
  29 # ifndef  CONFIG_ENV_ADDR
  30 #  define CONFIG_ENV_ADDR       (CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET)
  31 # endif
  32 # ifndef  CONFIG_ENV_SIZE
  33 #  define CONFIG_ENV_SIZE       CONFIG_ENV_SECT_SIZE
  34 # endif
  35 # ifndef  CONFIG_ENV_SECT_SIZE
  36 #  define CONFIG_ENV_SECT_SIZE  CONFIG_ENV_SIZE
  37 # endif
  38 #endif
  39
  40 /*
  41  * Use buffered writes to flash by default - they are about 32x faster than
  42  * single byte writes.
  43  */
  44 #ifndef  CONFIG_SYS_GEN860T_FLASH_USE_WRITE_BUFFER
  45 #define CONFIG_SYS_GEN860T_FLASH_USE_WRITE_BUFFER
  46 #endif
  47
  48 /*
  49  * Max time to wait (in mS) for flash device to allocate a write buffer.
  50  */
  51 #ifndef CONFIG_SYS_FLASH_ALLOC_BUFFER_TOUT
  52 #define CONFIG_SYS_FLASH_ALLOC_BUFFER_TOUT              100
  53 #endif
  54
  55 /*
  56  * These functions support a single Intel StrataFlash device (28F128J3A)
  57  * in byte mode only!.  The flash routines are very basic and simple
  58  * since there isn't really any remapping necessary.
  59  */
  60
  61 /*
  62  * Intel SCS (Scalable Command Set) command definitions
  63  * (taken from 28F128J3A datasheet)
  64  */
  65 #define SCS_READ_CMD                            0xff
  66 #define SCS_READ_ID_CMD                         0x90
  67 #define SCS_QUERY_CMD                           0x98
  68 #define SCS_READ_STATUS_CMD                     0x70
  69 #define SCS_CLEAR_STATUS_CMD            0x50
  70 #define SCS_WRITE_BUF_CMD                       0xe8
  71 #define SCS_PROGRAM_CMD                         0x40
  72 #define SCS_BLOCK_ERASE_CMD                     0x20
  73 #define SCS_BLOCK_ERASE_RESUME_CMD      0xd0
  74 #define SCS_PROGRAM_RESUME_CMD          0xd0
  75 #define SCS_BLOCK_ERASE_SUSPEND_CMD     0xb0
  76 #define SCS_SET_BLOCK_LOCK_CMD          0x60
  77 #define SCS_CLR_BLOCK_LOCK_CMD          0x60
  78
  79 /*
  80  * SCS status/extended status register bit definitions
  81  */
  82 #define  SCS_SR7                                        0x80
  83 #define  SCS_XSR7                                       0x80
  84
  85 /*---------------------------------------------------------------------*/
  86 #if 0
  87 #define DEBUG_FLASH
  88 #endif
  89
  90 #ifdef DEBUG_FLASH
  91 #define PRINTF(fmt,args...) printf(fmt ,##args)
  92 #else
  93 #define PRINTF(fmt,args...)
  94 #endif
  95 /*---------------------------------------------------------------------*/
  96
  97 flash_info_t    flash_info[CONFIG_SYS_MAX_FLASH_BANKS];
  98
  99 /*-----------------------------------------------------------------------
 100  * Functions
 101  */
 102 static ulong flash_get_size (vu_char *addr, flash_info_t *info);
 103 static int write_data8 (flash_info_t *info, ulong dest, uchar data);
 104 static void flash_get_offsets (ulong base, flash_info_t *info);
 105
 106 /*-----------------------------------------------------------------------
 107  * Initialize the flash memory.
 108  */
 109 unsigned long
 110 flash_init (void)
 111 {
 112         volatile immap_t     *immap  = (immap_t *)CONFIG_SYS_IMMR;
 113         volatile memctl8xx_t *memctl = &immap->im_memctl;
 114         unsigned long size_b0;
 115         int i;
 116
 117         for (i= 0; i < CONFIG_SYS_MAX_FLASH_BANKS; ++i) {
 118                 flash_info[i].flash_id = FLASH_UNKNOWN;
 119         }
 120
 121         /*
 122          * The gen860t board only has one FLASH memory device, so the
 123          * FLASH Bank configuration is done statically.
 124          */
 125         PRINTF("\n## Get flash bank 1 size @ 0x%08x\n", FLASH_BASE0_PRELIM);
 126         size_b0 = flash_get_size((vu_char *)FLASH_BASE0_PRELIM, &flash_info[0]);
 127         if (flash_info[0].flash_id == FLASH_UNKNOWN) {
 128                 printf ("## Unknown FLASH on Bank 0: "
 129                                 "ID 0x%lx, Size = 0x%08lx = %ld MB\n",
 130                                 flash_info[0].flash_id,size_b0, size_b0 << 20);
 131         }
 132
 133         PRINTF("## Before remap:\n"
 134                    "  BR0: 0x%08x    OR0: 0x%08x\n  BR1: 0x%08x    OR1: 0x%08x\n",
 135                    memctl->memc_br0, memctl->memc_or0,
 136                    memctl->memc_br1, memctl->memc_or1);
 137
 138         /*
 139          * Remap FLASH according to real size
 140          */
 141         memctl->memc_or0 |= (-size_b0 & 0xFFFF8000);
 142         memctl->memc_br0 |= (CONFIG_SYS_FLASH_BASE & BR_BA_MSK);
 143
 144         PRINTF("## After remap:\n"
 145                    "  BR0: 0x%08x    OR0: 0x%08x\n", memctl->memc_br0, memctl->memc_or0);
 146
 147         /*
 148          * Re-do sizing to get full correct info
 149          */
 150         size_b0 = flash_get_size ((vu_char *)CONFIG_SYS_FLASH_BASE, &flash_info[0]);
 151         flash_get_offsets (CONFIG_SYS_FLASH_BASE, &flash_info[0]);
 152         flash_info[0].size = size_b0;
 153
 154 #if CONFIG_SYS_MONITOR_BASE >= CONFIG_SYS_FLASH_BASE
 155         /*
 156          * Monitor protection is ON by default
 157          */
 158         flash_protect(FLAG_PROTECT_SET,
 159                           CONFIG_SYS_MONITOR_BASE,
 160                           CONFIG_SYS_MONITOR_BASE + monitor_flash_len - 1,
 161                           &flash_info[0]);
 162 #endif
 163
 164 #ifdef  CONFIG_ENV_IS_IN_FLASH
 165         /*
 166          * Environment protection ON by default
 167          */
 168         flash_protect(FLAG_PROTECT_SET,
 169                           CONFIG_ENV_ADDR,
 170                           CONFIG_ENV_ADDR + CONFIG_ENV_SECT_SIZE - 1,
 171                           &flash_info[0]);
 172 #endif
 173
 174         PRINTF("## Final Flash bank size: 0x%08lx\n",size_b0);
 175         return (size_b0);
 176 }
 177
 178
 179 /*-----------------------------------------------------------------------
 180  * Fill in the FLASH offset table
 181  */
 182 static void
 183 flash_get_offsets (ulong base, flash_info_t *info)
 184 {
 185         int i;
 186
 187         if (info->flash_id == FLASH_UNKNOWN) {
 188                 return;
 189         }
 190
 191         switch (info->flash_id & FLASH_VENDMASK) {
 192                 case FLASH_MAN_INTEL:
 193                 for (i = 0; i < info->sector_count; i++) {
 194                                 info->start[i] = base;
 195                                 base += 1024 * 128;
 196                 }
 197                 return;
 198
 199                 default:
 200                         printf ("Don't know sector offsets for FLASH"
 201                                 " type 0x%lx\n", info->flash_id);
 202             return;
 203         }
 204 }
 205
 206
 207 /*-----------------------------------------------------------------------
 208  * Display FLASH device info
 209  */
 210 void
 211 flash_print_info (flash_info_t *info)
 212 {
 213         int i;
 214
 215         if (info->flash_id == FLASH_UNKNOWN) {
 216                 printf ("Missing or unknown FLASH type\n");
 217                 return;
 218         }
 219
 220         switch (info->flash_id & FLASH_VENDMASK) {
 221         case FLASH_MAN_INTEL:
 222                         printf ("Intel ");
 223                         break;
 224         default:
 225                         printf ("Unknown Vendor ");
 226                         break;
 227         }
 228
 229         switch (info->flash_id & FLASH_TYPEMASK) {
 230         case FLASH_28F128J3A:
 231                         printf ("28F128J3A (128Mbit = 128K x 128)\n");
 232                         break;
 233         default:
 234                         printf ("Unknown Chip Type\n");
 235                         break;
 236         }
 237
 238         if (info->size >= (1024 * 1024)) {
 239                 i = 20;
 240         } else {
 241                 i = 10;
 242         }
 243         printf ("  Size: %ld %cB in %d Sectors\n",
 244                         info->size >> i,
 245                         (i == 20) ? 'M' : 'k',
 246                         info->sector_count);
 247
 248         printf ("  Sector Start Addresses:");
 249         for (i=0; i<info->sector_count; ++i) {
 250                 if ((i % 5) == 0)
 251                         printf ("\n   ");
 252                         printf (" %08lX%s",
 253                         info->start[i],
 254                         info->protect[i] ? " (RO)" : "     "
 255                 );
 256         }
 257         printf ("\n");
 258         return;
 259 }
 260
 261
 262 /*-----------------------------------------------------------------------
 263  * Get size and other information for a FLASH device.
 264  * NOTE: The following code cannot be run from FLASH!
 265  */
 266 static
 267 ulong flash_get_size (vu_char *addr, flash_info_t *info)
 268 {
 269 #define NO_FLASH        0
 270
 271         vu_char value[2];
 272
 273         /*
 274          * Try to read the manufacturer ID
 275          */
 276         addr[0] = SCS_READ_CMD;
 277         addr[0] = SCS_READ_ID_CMD;
 278         value[0] = addr[0];
 279         value[1] = addr[2];
 280         addr[0] = SCS_READ_CMD;
 281
 282         PRINTF("Manuf. ID @ 0x%08lx: 0x%02x\n", (ulong)addr, value[0]);
 283         switch (value[0]) {
 284                 case (INTEL_MANUFACT & 0xff):
 285                         info->flash_id = FLASH_MAN_INTEL;
 286                         break;
 287                 default:
 288                         info->flash_id = FLASH_UNKNOWN;
 289                         info->sector_count = 0;
 290                         info->size = 0;
 291                         return (NO_FLASH);
 292         }
 293
 294         /*
 295          * Read the device ID
 296          */
 297         PRINTF("Device ID @ 0x%08lx: 0x%02x\n", (ulong)(&addr[2]), value[1]);
 298         switch (value[1]) {
 299                 case (INTEL_ID_28F128J3A & 0xff):
 300                         info->flash_id += FLASH_28F128J3A;
 301                         info->sector_count = 128;
 302                         info->size = 16 * 1024 * 1024;
 303                         break;
 304
 305                 default:
 306                         info->flash_id = FLASH_UNKNOWN;
 307                         return (NO_FLASH);
 308         }
 309
 310         if (info->sector_count > CONFIG_SYS_MAX_FLASH_SECT) {
 311                 printf ("** ERROR: sector count %d > max (%d) **\n",
 312                                 info->sector_count, CONFIG_SYS_MAX_FLASH_SECT);
 313                                 info->sector_count = CONFIG_SYS_MAX_FLASH_SECT;
 314         }
 315         return (info->size);
 316 }
 317
 318
 319 /*-----------------------------------------------------------------------
 320  * Erase the specified sectors in the specified FLASH device
 321  */
 322 int
 323 flash_erase(flash_info_t *info, int s_first, int s_last)
 324 {
 325         int flag, prot, sect;
 326         ulong start, now, last;
 327
 328         if ((s_first < 0) || (s_first > s_last)) {
 329                 if (info->flash_id == FLASH_UNKNOWN) {
 330                         printf ("- missing\n");
 331                 } else {
 332                         printf ("- no sectors to erase\n");
 333                 }
 334                 return 1;
 335         }
 336
 337         if ((info->flash_id & FLASH_VENDMASK) != FLASH_MAN_INTEL) {
 338                 printf ("Can erase only Intel flash types - aborted\n");
 339                 return 1;
 340         }
 341
 342         prot = 0;
 343         for (sect=s_first; sect<=s_last; ++sect) {
 344                 if (info->protect[sect]) {
 345                         prot++;
 346                 }
 347         }
 348
 349         if (prot) {
 350                 printf ("- Warning: %d protected sectors will not be erased!\n",
 351                                 prot);
 352         } else {
 353                 printf ("\n");
 354         }
 355
 356         start = get_timer (0);
 357         last  = start;
 358
 359         /*
 360          * Start erase on unprotected sectors
 361          */
 362         for (sect = s_first; sect<=s_last; sect++) {
 363                 if (info->protect[sect] == 0) { /* not protected */
 364                         vu_char *addr = (uchar *)(info->start[sect]);
 365                         vu_char status;
 366
 367                         /*
 368                          * Disable interrupts which might cause a timeout
 369                          */
 370                         flag = disable_interrupts();
 371
 372                         *addr = SCS_CLEAR_STATUS_CMD;
 373                         *addr = SCS_BLOCK_ERASE_CMD;
 374                         *addr = SCS_BLOCK_ERASE_RESUME_CMD;
 375
 376                         /*
 377                          * Re-enable interrupts if necessary
 378                          */
 379                         if (flag)
 380                                 enable_interrupts();
 381
 382                         /*
 383                          * Wait at least 80us - let's wait 1 ms
 384                          */
 385                         udelay (1000);
 386
 387                         while (((status = *addr) & SCS_SR7) != SCS_SR7) {
 388                                 if ((now=get_timer(start)) > CONFIG_SYS_FLASH_ERASE_TOUT) {
 389                                         printf ("Timeout\n");
 390                                         *addr = SCS_BLOCK_ERASE_SUSPEND_CMD;
 391                                         *addr = SCS_READ_CMD;
 392                                         return 1;
 393                                 }
 394
 395                                 /*
 396                                  * Show that we're waiting
 397                                  */
 398                                 if ((now - last) > 1000) {      /* 1 second */
 399                                         putc ('.');
 400                                         last = now;
 401                                 }
 402                         }
 403                         *addr = SCS_READ_CMD;
 404                 }
 405         }
 406         printf (" done\n");
 407         return 0;
 408 }
 409
 410
 411 #ifdef CONFIG_SYS_GEN860T_FLASH_USE_WRITE_BUFFER
 412 /*
 413  * Allocate a flash buffer, fill it with data and write it to the flash.
 414  * 0 - OK
 415  * 1 - Timeout on buffer request
 416  *
 417  * NOTE: After the last call to this function, WSM status needs to be checked!
 418  */
 419 static int
 420 write_flash_buffer8(flash_info_t *info_p, vu_char *src_p, vu_char *dest_p,
 421                                     uint count)
 422 {
 423         vu_char *block_addr_p = NULL;
 424         vu_char *start_addr_p = NULL;
 425         ulong blocksize = info_p->size / (ulong)info_p->sector_count;
 426
 427         int i;
 428         uint time = get_timer(0);
 429
 430         PRINTF("%s:%d: src: 0x%p dest: 0x%p  count: %d\n",
 431                    __FUNCTION__, __LINE__, src_p, dest_p, count);
 432
 433         /*
 434          * What block are we in? We already know that the source address is
 435          * in the flash address range, but we also can't cross a block boundary.
 436          * We assume that the block does not cross a boundary (we'll check before
 437          * calling this function).
 438          */
 439         for (i = 0; i < info_p->sector_count; ++i) {
 440                 if ( ((ulong)dest_p >= info_p->start[i]) &&
 441                     ((ulong)dest_p < (info_p->start[i] + blocksize)) ) {
 442                         PRINTF("%s:%d: Dest addr 0x%p is in block %d @ 0x%.8lx\n",
 443                                    __FUNCTION__, __LINE__, dest_p, i, info_p->start[i]);
 444                         block_addr_p = (vu_char *)info_p->start[i];
 445                         break;
 446                 }
 447         }
 448
 449         /*
 450          * Request a buffer
 451          */
 452         *block_addr_p = SCS_WRITE_BUF_CMD;
 453         while ((*block_addr_p & SCS_XSR7) != SCS_XSR7) {
 454                 if (get_timer(time) >  CONFIG_SYS_FLASH_ALLOC_BUFFER_TOUT) {
 455                         PRINTF("%s:%d: Buffer allocation timeout @ 0x%p (waited %d mS)\n",
 456                                    __FUNCTION__, __LINE__, block_addr_p,
 457                                    CONFIG_SYS_FLASH_ALLOC_BUFFER_TOUT);
 458                         return 1;
 459                 }
 460                 *block_addr_p = SCS_WRITE_BUF_CMD;
 461         }
 462
 463         /*
 464          * Fill the buffer with data
 465          */
 466         start_addr_p = dest_p;
 467         *block_addr_p = count - 1; /* flash device wants count - 1 */
 468         PRINTF("%s:%d: Fill buffer at block addr 0x%p\n",
 469                    __FUNCTION__, __LINE__, block_addr_p);
 470         for (i = 0; i < count; i++) {
 471                 *start_addr_p++ = *src_p++;
 472         }
 473
 474         /*
 475          * Flush buffer to flash
 476          */
 477         *block_addr_p = SCS_PROGRAM_RESUME_CMD;
 478 #if 1
 479         time = get_timer(0);
 480         while ((*block_addr_p & SCS_SR7) != SCS_SR7) {
 481                 if (get_timer(time) >  CONFIG_SYS_FLASH_WRITE_TOUT) {
 482                         PRINTF("%s:%d: Write timeout @ 0x%p (waited %d mS)\n",
 483                                    __FUNCTION__, __LINE__, block_addr_p, CONFIG_SYS_FLASH_WRITE_TOUT);
 484                         return 1;
 485                 }
 486         }
 487
 488 #endif
 489         return 0;
 490 }
 491 #endif
 492
 493
 494 /*-----------------------------------------------------------------------
 495  * Copy memory to flash, returns:
 496  * 0 - OK
 497  * 1 - write timeout
 498  * 2 - Flash not erased
 499  * 4 - Flash not identified
 500  */
 501 int
 502 write_buff(flash_info_t *info_p, uchar *src_p, ulong addr, ulong count)
 503 {
 504         int rc = 0;
 505 #ifdef CONFIG_SYS_GEN860T_FLASH_USE_WRITE_BUFFER
 506 #define FLASH_WRITE_BUF_SIZE    0x00000020      /* 32 bytes */
 507         int i;
 508         uint bufs;
 509         ulong buf_count;
 510         vu_char *sp;
 511         vu_char *dp;
 512 #else
 513         ulong wp;
 514 #endif
 515
 516         PRINTF("\n%s:%d: src: 0x%.8lx dest: 0x%.8lx size: %d (0x%.8lx)\n",
 517                    __FUNCTION__, __LINE__, (ulong)src_p, addr, (uint)count, count);
 518
 519         if (info_p->flash_id == FLASH_UNKNOWN) {
 520                 return 4;
 521         }
 522
 523 #ifdef CONFIG_SYS_GEN860T_FLASH_USE_WRITE_BUFFER
 524         sp = src_p;
 525         dp = (uchar *)addr;
 526
 527         /*
 528          * For maximum performance, we want to align the start address to
 529          * the beginning of a write buffer boundary (i.e. A4-A0 of the
 530          * start address = 0). See how many bytes are required to get to a
 531          * write-buffer-aligned address.  If that number is non-zero, do
 532          * non buffered writes of the non-aligned data.  By doing non-buffered
 533          * writes, we avoid the problem of crossing a block (sector) boundary
 534          * with buffered writes.
 535          */
 536         buf_count = FLASH_WRITE_BUF_SIZE - (addr & (FLASH_WRITE_BUF_SIZE - 1));
 537         if (buf_count == FLASH_WRITE_BUF_SIZE) { /* already on a boundary */
 538                 buf_count = 0;
 539         }
 540         if (buf_count > count) { /* not a full buffers worth of data to write */
 541                 buf_count = count;
 542         }
 543         count -= buf_count;
 544
 545         PRINTF("%s:%d: Write buffer alignment count = %ld\n",
 546                    __FUNCTION__, __LINE__, buf_count);
 547         while (buf_count-- >= 1) {
 548                 if ((rc = write_data8(info_p, (ulong)dp++, *sp++)) != 0)  {
 549                         return (rc);
 550                 }
 551         }
 552
 553         PRINTF("%s:%d: count = %ld\n", __FUNCTION__, __LINE__, count);
 554         if (count == 0) { /* all done */
 555                 PRINTF("%s:%d: Less than 1 buffer (%d) worth of bytes\n",
 556                            __FUNCTION__, __LINE__, FLASH_WRITE_BUF_SIZE);
 557                 return (rc);
 558         }
 559
 560         /*
 561          * Now that we are write buffer aligned, write full or partial buffers.
 562          * The fact that we are write buffer aligned automatically avoids
 563          * crossing a block address during a write buffer operation.
 564          */
 565         bufs = count / FLASH_WRITE_BUF_SIZE;
 566         PRINTF("%s:%d: %d (0x%x) buffers to write\n", __FUNCTION__, __LINE__,
 567                    bufs, bufs);
 568         while (bufs >= 1) {
 569                 rc = write_flash_buffer8(info_p, sp, dp, FLASH_WRITE_BUF_SIZE);
 570                 if (rc != 0) {
 571                         PRINTF("%s:%d: ** Error writing buf %d\n",
 572                                    __FUNCTION__, __LINE__, bufs);
 573                         return (rc);
 574                 }
 575                 bufs--;
 576                 sp += FLASH_WRITE_BUF_SIZE;
 577                 dp += FLASH_WRITE_BUF_SIZE;
 578         }
 579
 580         /*
 581          * Do the leftovers
 582          */
 583         i = count % FLASH_WRITE_BUF_SIZE;
 584         PRINTF("%s:%d: %d (0x%x) leftover bytes\n", __FUNCTION__, __LINE__, i, i);
 585         if (i > 0) {
 586                 rc = write_flash_buffer8(info_p, sp, dp, i);
 587         }
 588
 589         sp = (vu_char*)info_p->start[0];
 590         *sp = SCS_READ_CMD;
 591         return (rc);
 592
 593 #else
 594         wp = addr;
 595         while (count-- >= 1) {
 596                 if((rc = write_data8(info_p, wp++, *src_p++)) != 0)
 597                         return (rc);
 598         }
 599         return 0;
 600 #endif
 601 }
 602
 603
 604 /*-----------------------------------------------------------------------
 605  * Write a byte to Flash, returns:
 606  * 0 - OK
 607  * 1 - write timeout
 608  * 2 - Flash not erased
 609  */
 610 static int
 611 write_data8 (flash_info_t *info, ulong dest, uchar data)
 612 {
 613         vu_char *addr = (vu_char *)dest;
 614         vu_char status;
 615         ulong start;
 616         int flag;
 617
 618         /* Check if Flash is (sufficiently) erased */
 619         if ((*addr & data) != data) {
 620                 return (2);
 621         }
 622         /* Disable interrupts which might cause a timeout here */
 623         flag = disable_interrupts();
 624
 625         *addr = SCS_PROGRAM_CMD;
 626         *addr = data;
 627
 628         /* re-enable interrupts if necessary */
 629         if (flag)
 630                 enable_interrupts();
 631
 632         start = get_timer (0);
 633
 634         while (((status = *addr) & SCS_SR7) != SCS_SR7) {
 635                 if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT) {
 636                         *addr = SCS_READ_CMD;
 637                         return (1);
 638                 }
 639         }
 640         *addr = SCS_READ_CMD;
 641         return (0);
 642 }
 643
 644 /* vim: set ts=4 sw=4 tw=78: */