drivers/mtd/nand/nand_util.c

   1 /*
   2  * drivers/mtd/nand/nand_util.c
   3  *
   4  * Copyright (C) 2006 by Weiss-Electronic GmbH.
   5  * All rights reserved.
   6  *
   7  * @author:     Guido Classen <clagix@gmail.com>
   8  * @descr:      NAND Flash support
   9  * @references: borrowed heavily from Linux mtd-utils code:
  10  *              flash_eraseall.c by Arcom Control System Ltd
  11  *              nandwrite.c by Steven J. Hill (sjhill@realitydiluted.com)
  12  *                             and Thomas Gleixner (tglx@linutronix.de)
  13  *
  14  * Copyright (C) 2008 Nokia Corporation: drop_ffs() function by
  15  * Artem Bityutskiy <dedekind1@gmail.com> from mtd-utils
  16  *
  17  * See file CREDITS for list of people who contributed to this
  18  * project.
  19  *
  20  * This program is free software; you can redistribute it and/or
  21  * modify it under the terms of the GNU General Public License version
  22  * 2 as published by the Free Software Foundation.
  23  *
  24  * This program is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with this program; if not, write to the Free Software
  31  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  32  * MA 02111-1307 USA
  33  *
  34  * Copyright 2010 Freescale Semiconductor
  35  * The portions of this file whose copyright is held by Freescale and which
  36  * are not considered a derived work of GPL v2-only code may be distributed
  37  * and/or modified under the terms of the GNU General Public License as
  38  * published by the Free Software Foundation; either version 2 of the
  39  * License, or (at your option) any later version.
  40  */
  41
  42 #include <common.h>
  43 #include <command.h>
  44 #include <watchdog.h>
  45 #include <malloc.h>
  46 #include <div64.h>
  47
  48 #include <asm/errno.h>
  49 #include <linux/mtd/mtd.h>
  50 #include <nand.h>
  51 #include <jffs2/jffs2.h>
  52
  53 typedef struct erase_info       erase_info_t;
  54 typedef struct mtd_info         mtd_info_t;
  55
  56 /* support only for native endian JFFS2 */
  57 #define cpu_to_je16(x) (x)
  58 #define cpu_to_je32(x) (x)
  59
  60 /**
  61  * nand_erase_opts: - erase NAND flash with support for various options
  62  *                    (jffs2 formatting)
  63  *
  64  * @param meminfo       NAND device to erase
  65  * @param opts          options,  @see struct nand_erase_options
  66  * @return              0 in case of success
  67  *
  68  * This code is ported from flash_eraseall.c from Linux mtd utils by
  69  * Arcom Control System Ltd.
  70  */
  71 int nand_erase_opts(nand_info_t *meminfo, const nand_erase_options_t *opts)
  72 {
  73         struct jffs2_unknown_node cleanmarker;
  74         erase_info_t erase;
  75         unsigned long erase_length, erased_length; /* in blocks */
  76         int bbtest = 1;
  77         int result;
  78         int percent_complete = -1;
  79         const char *mtd_device = meminfo->name;
  80         struct mtd_oob_ops oob_opts;
  81         struct nand_chip *chip = meminfo->priv;
  82
  83         if ((opts->offset & (meminfo->erasesize - 1)) != 0) {
  84                 printf("Attempt to erase non block-aligned data\n");
  85                 return -1;
  86         }
  87
  88         memset(&erase, 0, sizeof(erase));
  89         memset(&oob_opts, 0, sizeof(oob_opts));
  90
  91         erase.mtd = meminfo;
  92         erase.len  = meminfo->erasesize;
  93         erase.addr = opts->offset;
  94         erase_length = lldiv(opts->length + meminfo->erasesize - 1,
  95                              meminfo->erasesize);
  96
  97         cleanmarker.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
  98         cleanmarker.nodetype = cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER);
  99         cleanmarker.totlen = cpu_to_je32(8);
 100
 101         /* scrub option allows to erase badblock. To prevent internal
 102          * check from erase() method, set block check method to dummy
 103          * and disable bad block table while erasing.
 104          */
 105         if (opts->scrub) {
 106                 erase.scrub = opts->scrub;
 107                 /*
 108                  * We don't need the bad block table anymore...
 109                  * after scrub, there are no bad blocks left!
 110                  */
 111                 if (chip->bbt) {
 112                         kfree(chip->bbt);
 113                 }
 114                 chip->bbt = NULL;
 115         }
 116
 117         for (erased_length = 0;
 118              erased_length < erase_length;
 119              erase.addr += meminfo->erasesize) {
 120
 121                 WATCHDOG_RESET();
 122
 123                 if (!opts->scrub && bbtest) {
 124                         int ret = meminfo->block_isbad(meminfo, erase.addr);
 125                         if (ret > 0) {
 126                                 if (!opts->quiet)
 127                                         printf("\rSkipping bad block at  "
 128                                                "0x%08llx                 "
 129                                                "                         \n",
 130                                                erase.addr);
 131
 132                                 if (!opts->spread)
 133                                         erased_length++;
 134
 135                                 continue;
 136
 137                         } else if (ret < 0) {
 138                                 printf("\n%s: MTD get bad block failed: %d\n",
 139                                        mtd_device,
 140                                        ret);
 141                                 return -1;
 142                         }
 143                 }
 144
 145                 erased_length++;
 146
 147                 result = meminfo->erase(meminfo, &erase);
 148                 if (result != 0) {
 149                         printf("\n%s: MTD Erase failure: %d\n",
 150                                mtd_device, result);
 151                         continue;
 152                 }
 153
 154                 /* format for JFFS2 ? */
 155                 if (opts->jffs2 && chip->ecc.layout->oobavail >= 8) {
 156                         chip->ops.ooblen = 8;
 157                         chip->ops.datbuf = NULL;
 158                         chip->ops.oobbuf = (uint8_t *)&cleanmarker;
 159                         chip->ops.ooboffs = 0;
 160                         chip->ops.mode = MTD_OOB_AUTO;
 161
 162                         result = meminfo->write_oob(meminfo,
 163                                                     erase.addr,
 164                                                     &chip->ops);
 165                         if (result != 0) {
 166                                 printf("\n%s: MTD writeoob failure: %d\n",
 167                                        mtd_device, result);
 168                                 continue;
 169                         }
 170                 }
 171
 172                 if (!opts->quiet) {
 173                         unsigned long long n = erased_length * 100ULL;
 174                         int percent;
 175
 176                         do_div(n, erase_length);
 177                         percent = (int)n;
 178
 179                         /* output progress message only at whole percent
 180                          * steps to reduce the number of messages printed
 181                          * on (slow) serial consoles
 182                          */
 183                         if (percent != percent_complete) {
 184                                 percent_complete = percent;
 185
 186                                 printf("\rErasing at 0x%llx -- %3d%% complete.",
 187                                        erase.addr, percent);
 188
 189                                 if (opts->jffs2 && result == 0)
 190                                         printf(" Cleanmarker written at 0x%llx.",
 191                                                erase.addr);
 192                         }
 193                 }
 194         }
 195         if (!opts->quiet)
 196                 printf("\n");
 197
 198         if (opts->scrub)
 199                 chip->scan_bbt(meminfo);
 200
 201         return 0;
 202 }
 203
 204 #ifdef CONFIG_CMD_NAND_LOCK_UNLOCK
 205
 206 /******************************************************************************
 207  * Support for locking / unlocking operations of some NAND devices
 208  *****************************************************************************/
 209
 210 /**
 211  * nand_lock: Set all pages of NAND flash chip to the LOCK or LOCK-TIGHT
 212  *            state
 213  *
 214  * @param mtd           nand mtd instance
 215  * @param tight         bring device in lock tight mode
 216  *
 217  * @return              0 on success, -1 in case of error
 218  *
 219  * The lock / lock-tight command only applies to the whole chip. To get some
 220  * parts of the chip lock and others unlocked use the following sequence:
 221  *
 222  * - Lock all pages of the chip using nand_lock(mtd, 0) (or the lockpre pin)
 223  * - Call nand_unlock() once for each consecutive area to be unlocked
 224  * - If desired: Bring the chip to the lock-tight state using nand_lock(mtd, 1)
 225  *
 226  *   If the device is in lock-tight state software can't change the
 227  *   current active lock/unlock state of all pages. nand_lock() / nand_unlock()
 228  *   calls will fail. It is only posible to leave lock-tight state by
 229  *   an hardware signal (low pulse on _WP pin) or by power down.
 230  */
 231 int nand_lock(struct mtd_info *mtd, int tight)
 232 {
 233         int ret = 0;
 234         int status;
 235         struct nand_chip *chip = mtd->priv;
 236
 237         /* select the NAND device */
 238         chip->select_chip(mtd, 0);
 239
 240         chip->cmdfunc(mtd,
 241                       (tight ? NAND_CMD_LOCK_TIGHT : NAND_CMD_LOCK),
 242                       -1, -1);
 243
 244         /* call wait ready function */
 245         status = chip->waitfunc(mtd, chip);
 246
 247         /* see if device thinks it succeeded */
 248         if (status & 0x01) {
 249                 ret = -1;
 250         }
 251
 252         /* de-select the NAND device */
 253         chip->select_chip(mtd, -1);
 254         return ret;
 255 }
 256
 257 /**
 258  * nand_get_lock_status: - query current lock state from one page of NAND
 259  *                         flash
 260  *
 261  * @param mtd           nand mtd instance
 262  * @param offset        page address to query (must be page-aligned!)
 263  *
 264  * @return              -1 in case of error
 265  *                      >0 lock status:
 266  *                        bitfield with the following combinations:
 267  *                        NAND_LOCK_STATUS_TIGHT: page in tight state
 268  *                        NAND_LOCK_STATUS_UNLOCK: page unlocked
 269  *
 270  */
 271 int nand_get_lock_status(struct mtd_info *mtd, loff_t offset)
 272 {
 273         int ret = 0;
 274         int chipnr;
 275         int page;
 276         struct nand_chip *chip = mtd->priv;
 277
 278         /* select the NAND device */
 279         chipnr = (int)(offset >> chip->chip_shift);
 280         chip->select_chip(mtd, chipnr);
 281
 282
 283         if ((offset & (mtd->writesize - 1)) != 0) {
 284                 printf("nand_get_lock_status: "
 285                         "Start address must be beginning of "
 286                         "nand page!\n");
 287                 ret = -1;
 288                 goto out;
 289         }
 290
 291         /* check the Lock Status */
 292         page = (int)(offset >> chip->page_shift);
 293         chip->cmdfunc(mtd, NAND_CMD_LOCK_STATUS, -1, page & chip->pagemask);
 294
 295         ret = chip->read_byte(mtd) & (NAND_LOCK_STATUS_TIGHT
 296                                           | NAND_LOCK_STATUS_UNLOCK);
 297
 298  out:
 299         /* de-select the NAND device */
 300         chip->select_chip(mtd, -1);
 301         return ret;
 302 }
 303
 304 /**
 305  * nand_unlock: - Unlock area of NAND pages
 306  *                only one consecutive area can be unlocked at one time!
 307  *
 308  * @param mtd           nand mtd instance
 309  * @param start         start byte address
 310  * @param length        number of bytes to unlock (must be a multiple of
 311  *                      page size nand->writesize)
 312  * @param allexcept     if set, unlock everything not selected
 313  *
 314  * @return              0 on success, -1 in case of error
 315  */
 316 int nand_unlock(struct mtd_info *mtd, loff_t start, size_t length,
 317         int allexcept)
 318 {
 319         int ret = 0;
 320         int chipnr;
 321         int status;
 322         int page;
 323         struct nand_chip *chip = mtd->priv;
 324
 325         debug("nand_unlock%s: start: %08llx, length: %d!\n",
 326                 allexcept ? " (allexcept)" : "", start, length);
 327
 328         /* select the NAND device */
 329         chipnr = (int)(start >> chip->chip_shift);
 330         chip->select_chip(mtd, chipnr);
 331
 332         /* check the WP bit */
 333         chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
 334         if (!(chip->read_byte(mtd) & NAND_STATUS_WP)) {
 335                 printf("nand_unlock: Device is write protected!\n");
 336                 ret = -1;
 337                 goto out;
 338         }
 339
 340         if ((start & (mtd->erasesize - 1)) != 0) {
 341                 printf("nand_unlock: Start address must be beginning of "
 342                         "nand block!\n");
 343                 ret = -1;
 344                 goto out;
 345         }
 346
 347         if (length == 0 || (length & (mtd->erasesize - 1)) != 0) {
 348                 printf("nand_unlock: Length must be a multiple of nand block "
 349                         "size %08x!\n", mtd->erasesize);
 350                 ret = -1;
 351                 goto out;
 352         }
 353
 354         /*
 355          * Set length so that the last address is set to the
 356          * starting address of the last block
 357          */
 358         length -= mtd->erasesize;
 359
 360         /* submit address of first page to unlock */
 361         page = (int)(start >> chip->page_shift);
 362         chip->cmdfunc(mtd, NAND_CMD_UNLOCK1, -1, page & chip->pagemask);
 363
 364         /* submit ADDRESS of LAST page to unlock */
 365         page += (int)(length >> chip->page_shift);
 366
 367         /*
 368          * Page addresses for unlocking are supposed to be block-aligned.
 369          * At least some NAND chips use the low bit to indicate that the
 370          * page range should be inverted.
 371          */
 372         if (allexcept)
 373                 page |= 1;
 374
 375         chip->cmdfunc(mtd, NAND_CMD_UNLOCK2, -1, page & chip->pagemask);
 376
 377         /* call wait ready function */
 378         status = chip->waitfunc(mtd, chip);
 379         /* see if device thinks it succeeded */
 380         if (status & 0x01) {
 381                 /* there was an error */
 382                 ret = -1;
 383                 goto out;
 384         }
 385
 386  out:
 387         /* de-select the NAND device */
 388         chip->select_chip(mtd, -1);
 389         return ret;
 390 }
 391 #endif
 392
 393 /**
 394  * check_skip_len
 395  *
 396  * Check if there are any bad blocks, and whether length including bad
 397  * blocks fits into device
 398  *
 399  * @param nand NAND device
 400  * @param offset offset in flash
 401  * @param length image length
 402  * @return 0 if the image fits and there are no bad blocks
 403  *         1 if the image fits, but there are bad blocks
 404  *        -1 if the image does not fit
 405  */
 406 static int check_skip_len(nand_info_t *nand, loff_t offset, size_t length)
 407 {
 408         size_t len_excl_bad = 0;
 409         int ret = 0;
 410
 411         while (len_excl_bad < length) {
 412                 size_t block_len, block_off;
 413                 loff_t block_start;
 414
 415                 if (offset >= nand->size)
 416                         return -1;
 417
 418                 block_start = offset & ~(loff_t)(nand->erasesize - 1);
 419                 block_off = offset & (nand->erasesize - 1);
 420                 block_len = nand->erasesize - block_off;
 421
 422                 if (!nand_block_isbad(nand, block_start))
 423                         len_excl_bad += block_len;
 424                 else
 425                         ret = 1;
 426
 427                 offset += block_len;
 428         }
 429
 430         return ret;
 431 }
 432
 433 #ifdef CONFIG_CMD_NAND_TRIMFFS
 434 static size_t drop_ffs(const nand_info_t *nand, const u_char *buf,
 435                         const size_t *len)
 436 {
 437         size_t i, l = *len;
 438
 439         for (i = l - 1; i >= 0; i--)
 440                 if (buf[i] != 0xFF)
 441                         break;
 442
 443         /* The resulting length must be aligned to the minimum flash I/O size */
 444         l = i + 1;
 445         l = (l + nand->writesize - 1) / nand->writesize;
 446         l *=  nand->writesize;
 447
 448         /*
 449          * since the input length may be unaligned, prevent access past the end
 450          * of the buffer
 451          */
 452         return min(l, *len);
 453 }
 454 #endif
 455
 456 /**
 457  * nand_write_skip_bad:
 458  *
 459  * Write image to NAND flash.
 460  * Blocks that are marked bad are skipped and the is written to the next
 461  * block instead as long as the image is short enough to fit even after
 462  * skipping the bad blocks.
 463  *
 464  * @param nand          NAND device
 465  * @param offset        offset in flash
 466  * @param length        buffer length
 467  * @param buffer        buffer to read from
 468  * @param flags         flags modifying the behaviour of the write to NAND
 469  * @return              0 in case of success
 470  */
 471 int nand_write_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,
 472                         u_char *buffer, int flags)
 473 {
 474         int rval = 0, blocksize;
 475         size_t left_to_write = *length;
 476         u_char *p_buffer = buffer;
 477         int need_skip;
 478
 479 #ifdef CONFIG_CMD_NAND_YAFFS
 480         if (flags & WITH_YAFFS_OOB) {
 481                 if (flags & ~WITH_YAFFS_OOB)
 482                         return -EINVAL;
 483
 484                 int pages;
 485                 pages = nand->erasesize / nand->writesize;
 486                 blocksize = (pages * nand->oobsize) + nand->erasesize;
 487                 if (*length % (nand->writesize + nand->oobsize)) {
 488                         printf("Attempt to write incomplete page"
 489                                 " in yaffs mode\n");
 490                         return -EINVAL;
 491                 }
 492         } else
 493 #endif
 494         {
 495                 blocksize = nand->erasesize;
 496         }
 497
 498         /*
 499          * nand_write() handles unaligned, partial page writes.
 500          *
 501          * We allow length to be unaligned, for convenience in
 502          * using the $filesize variable.
 503          *
 504          * However, starting at an unaligned offset makes the
 505          * semantics of bad block skipping ambiguous (really,
 506          * you should only start a block skipping access at a
 507          * partition boundary).  So don't try to handle that.
 508          */
 509         if ((offset & (nand->writesize - 1)) != 0) {
 510                 printf("Attempt to write non page-aligned data\n");
 511                 *length = 0;
 512                 return -EINVAL;
 513         }
 514
 515         need_skip = check_skip_len(nand, offset, *length);
 516         if (need_skip < 0) {
 517                 printf("Attempt to write outside the flash area\n");
 518                 *length = 0;
 519                 return -EINVAL;
 520         }
 521
 522         if (!need_skip && !(flags & WITH_DROP_FFS)) {
 523                 rval = nand_write(nand, offset, length, buffer);
 524                 if (rval == 0)
 525                         return 0;
 526
 527                 *length = 0;
 528                 printf("NAND write to offset %llx failed %d\n",
 529                         offset, rval);
 530                 return rval;
 531         }
 532
 533         while (left_to_write > 0) {
 534                 size_t block_offset = offset & (nand->erasesize - 1);
 535                 size_t write_size, truncated_write_size;
 536
 537                 WATCHDOG_RESET();
 538
 539                 if (nand_block_isbad(nand, offset & ~(nand->erasesize - 1))) {
 540                         printf("Skip bad block 0x%08llx\n",
 541                                 offset & ~(nand->erasesize - 1));
 542                         offset += nand->erasesize - block_offset;
 543                         continue;
 544                 }
 545
 546                 if (left_to_write < (blocksize - block_offset))
 547                         write_size = left_to_write;
 548                 else
 549                         write_size = blocksize - block_offset;
 550
 551 #ifdef CONFIG_CMD_NAND_YAFFS
 552                 if (flags & WITH_YAFFS_OOB) {
 553                         int page, pages;
 554                         size_t pagesize = nand->writesize;
 555                         size_t pagesize_oob = pagesize + nand->oobsize;
 556                         struct mtd_oob_ops ops;
 557
 558                         ops.len = pagesize;
 559                         ops.ooblen = nand->oobsize;
 560                         ops.mode = MTD_OOB_AUTO;
 561                         ops.ooboffs = 0;
 562
 563                         pages = write_size / pagesize_oob;
 564                         for (page = 0; page < pages; page++) {
 565                                 WATCHDOG_RESET();
 566
 567                                 ops.datbuf = p_buffer;
 568                                 ops.oobbuf = ops.datbuf + pagesize;
 569
 570                                 rval = nand->write_oob(nand, offset, &ops);
 571                                 if (rval != 0)
 572                                         break;
 573
 574                                 offset += pagesize;
 575                                 p_buffer += pagesize_oob;
 576                         }
 577                 }
 578                 else
 579 #endif
 580                 {
 581                         truncated_write_size = write_size;
 582 #ifdef CONFIG_CMD_NAND_TRIMFFS
 583                         if (flags & WITH_DROP_FFS)
 584                                 truncated_write_size = drop_ffs(nand, p_buffer,
 585                                                 &write_size);
 586 #endif
 587
 588                         rval = nand_write(nand, offset, &truncated_write_size,
 589                                         p_buffer);
 590                         offset += write_size;
 591                         p_buffer += write_size;
 592                 }
 593
 594                 if (rval != 0) {
 595                         printf("NAND write to offset %llx failed %d\n",
 596                                 offset, rval);
 597                         *length -= left_to_write;
 598                         return rval;
 599                 }
 600
 601                 left_to_write -= write_size;
 602         }
 603
 604         return 0;
 605 }
 606
 607 /**
 608  * nand_read_skip_bad:
 609  *
 610  * Read image from NAND flash.
 611  * Blocks that are marked bad are skipped and the next block is read
 612  * instead as long as the image is short enough to fit even after skipping the
 613  * bad blocks.
 614  *
 615  * @param nand NAND device
 616  * @param offset offset in flash
 617  * @param length buffer length, on return holds number of read bytes
 618  * @param buffer buffer to write to
 619  * @return 0 in case of success
 620  */
 621 int nand_read_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,
 622                        u_char *buffer)
 623 {
 624         int rval;
 625         size_t left_to_read = *length;
 626         u_char *p_buffer = buffer;
 627         int need_skip;
 628
 629         if ((offset & (nand->writesize - 1)) != 0) {
 630                 printf("Attempt to read non page-aligned data\n");
 631                 *length = 0;
 632                 return -EINVAL;
 633         }
 634
 635         need_skip = check_skip_len(nand, offset, *length);
 636         if (need_skip < 0) {
 637                 printf("Attempt to read outside the flash area\n");
 638                 *length = 0;
 639                 return -EINVAL;
 640         }
 641
 642         if (!need_skip) {
 643                 rval = nand_read(nand, offset, length, buffer);
 644                 if (!rval || rval == -EUCLEAN)
 645                         return 0;
 646
 647                 *length = 0;
 648                 printf("NAND read from offset %llx failed %d\n",
 649                         offset, rval);
 650                 return rval;
 651         }
 652
 653         while (left_to_read > 0) {
 654                 size_t block_offset = offset & (nand->erasesize - 1);
 655                 size_t read_length;
 656
 657                 WATCHDOG_RESET();
 658
 659                 if (nand_block_isbad(nand, offset & ~(nand->erasesize - 1))) {
 660                         printf("Skipping bad block 0x%08llx\n",
 661                                 offset & ~(nand->erasesize - 1));
 662                         offset += nand->erasesize - block_offset;
 663                         continue;
 664                 }
 665
 666                 if (left_to_read < (nand->erasesize - block_offset))
 667                         read_length = left_to_read;
 668                 else
 669                         read_length = nand->erasesize - block_offset;
 670
 671                 rval = nand_read(nand, offset, &read_length, p_buffer);
 672                 if (rval && rval != -EUCLEAN) {
 673                         printf("NAND read from offset %llx failed %d\n",
 674                                 offset, rval);
 675                         *length -= left_to_read;
 676                         return rval;
 677                 }
 678
 679                 left_to_read -= read_length;
 680                 offset       += read_length;
 681                 p_buffer     += read_length;
 682         }
 683
 684         return 0;
 685 }
 686
 687 #ifdef CONFIG_CMD_NAND_TORTURE
 688
 689 /**
 690  * check_pattern:
 691  *
 692  * Check if buffer contains only a certain byte pattern.
 693  *
 694  * @param buf buffer to check
 695  * @param patt the pattern to check
 696  * @param size buffer size in bytes
 697  * @return 1 if there are only patt bytes in buf
 698  *         0 if something else was found
 699  */
 700 static int check_pattern(const u_char *buf, u_char patt, int size)
 701 {
 702         int i;
 703
 704         for (i = 0; i < size; i++)
 705                 if (buf[i] != patt)
 706                         return 0;
 707         return 1;
 708 }
 709
 710 /**
 711  * nand_torture:
 712  *
 713  * Torture a block of NAND flash.
 714  * This is useful to determine if a block that caused a write error is still
 715  * good or should be marked as bad.
 716  *
 717  * @param nand NAND device
 718  * @param offset offset in flash
 719  * @return 0 if the block is still good
 720  */
 721 int nand_torture(nand_info_t *nand, loff_t offset)
 722 {
 723         u_char patterns[] = {0xa5, 0x5a, 0x00};
 724         struct erase_info instr = {
 725                 .mtd = nand,
 726                 .addr = offset,
 727                 .len = nand->erasesize,
 728         };
 729         size_t retlen;
 730         int err, ret = -1, i, patt_count;
 731         u_char *buf;
 732
 733         if ((offset & (nand->erasesize - 1)) != 0) {
 734                 puts("Attempt to torture a block at a non block-aligned offset\n");
 735                 return -EINVAL;
 736         }
 737
 738         if (offset + nand->erasesize > nand->size) {
 739                 puts("Attempt to torture a block outside the flash area\n");
 740                 return -EINVAL;
 741         }
 742
 743         patt_count = ARRAY_SIZE(patterns);
 744
 745         buf = malloc(nand->erasesize);
 746         if (buf == NULL) {
 747                 puts("Out of memory for erase block buffer\n");
 748                 return -ENOMEM;
 749         }
 750
 751         for (i = 0; i < patt_count; i++) {
 752                 err = nand->erase(nand, &instr);
 753                 if (err) {
 754                         printf("%s: erase() failed for block at 0x%llx: %d\n",
 755                                 nand->name, instr.addr, err);
 756                         goto out;
 757                 }
 758
 759                 /* Make sure the block contains only 0xff bytes */
 760                 err = nand->read(nand, offset, nand->erasesize, &retlen, buf);
 761                 if ((err && err != -EUCLEAN) || retlen != nand->erasesize) {
 762                         printf("%s: read() failed for block at 0x%llx: %d\n",
 763                                 nand->name, instr.addr, err);
 764                         goto out;
 765                 }
 766
 767                 err = check_pattern(buf, 0xff, nand->erasesize);
 768                 if (!err) {
 769                         printf("Erased block at 0x%llx, but a non-0xff byte was found\n",
 770                                 offset);
 771                         ret = -EIO;
 772                         goto out;
 773                 }
 774
 775                 /* Write a pattern and check it */
 776                 memset(buf, patterns[i], nand->erasesize);
 777                 err = nand->write(nand, offset, nand->erasesize, &retlen, buf);
 778                 if (err || retlen != nand->erasesize) {
 779                         printf("%s: write() failed for block at 0x%llx: %d\n",
 780                                 nand->name, instr.addr, err);
 781                         goto out;
 782                 }
 783
 784                 err = nand->read(nand, offset, nand->erasesize, &retlen, buf);
 785                 if ((err && err != -EUCLEAN) || retlen != nand->erasesize) {
 786                         printf("%s: read() failed for block at 0x%llx: %d\n",
 787                                 nand->name, instr.addr, err);
 788                         goto out;
 789                 }
 790
 791                 err = check_pattern(buf, patterns[i], nand->erasesize);
 792                 if (!err) {
 793                         printf("Pattern 0x%.2x checking failed for block at "
 794                                         "0x%llx\n", patterns[i], offset);
 795                         ret = -EIO;
 796                         goto out;
 797                 }
 798         }
 799
 800         ret = 0;
 801
 802 out:
 803         free(buf);
 804         return ret;
 805 }
 806
 807 #endif