LXR uboot/include/linux/mtd/bbm.h

   1/*
   2 *  linux/include/linux/mtd/bbm.h
   3 *
   4 *  NAND family Bad Block Management (BBM) header file
   5 *    - Bad Block Table (BBT) implementation
   6 *
   7 *  Copyright (c) 2005-2007 Samsung Electronics
   8 *  Kyungmin Park <kyungmin.park@samsung.com>
   9 *
  10 *  Copyright (c) 2000-2005
  11 *  Thomas Gleixner <tglx@linuxtronix.de>
  12 *
  13 * This program is free software; you can redistribute it and/or modify
  14 * it under the terms of the GNU General Public License version 2 as
  15 * published by the Free Software Foundation.
  16 */
  17#ifndef __LINUX_MTD_BBM_H
  18#define __LINUX_MTD_BBM_H
  19
  20/* The maximum number of NAND chips in an array */
  21#ifndef CONFIG_SYS_NAND_MAX_CHIPS
  22#define CONFIG_SYS_NAND_MAX_CHIPS       1
  23#endif
  24
  25/**
  26 * struct nand_bbt_descr - bad block table descriptor
  27 * @param options       options for this descriptor
  28 * @param pages         the page(s) where we find the bbt, used with
  29 *                      option BBT_ABSPAGE when bbt is searched,
  30 *                      then we store the found bbts pages here.
  31 *                      Its an array and supports up to 8 chips now
  32 * @param offs          offset of the pattern in the oob area of the page
  33 * @param veroffs       offset of the bbt version counter in the oob are of the page
  34 * @param version       version read from the bbt page during scan
  35 * @param len           length of the pattern, if 0 no pattern check is performed
  36 * @param maxblocks     maximum number of blocks to search for a bbt. This number of
  37 *                      blocks is reserved at the end of the device
  38 *                      where the tables are written.
  39 * @param reserved_block_code   if non-0, this pattern denotes a reserved
  40 *                      (rather than bad) block in the stored bbt
  41 * @param pattern       pattern to identify bad block table or factory marked
  42 *                      good / bad blocks, can be NULL, if len = 0
  43 *
  44 * Descriptor for the bad block table marker and the descriptor for the
  45 * pattern which identifies good and bad blocks. The assumption is made
  46 * that the pattern and the version count are always located in the oob area
  47 * of the first block.
  48 */
  49struct nand_bbt_descr {
  50        int options;
  51        int pages[CONFIG_SYS_NAND_MAX_CHIPS];
  52        int offs;
  53        int veroffs;
  54        uint8_t version[CONFIG_SYS_NAND_MAX_CHIPS];
  55        int len;
  56        int maxblocks;
  57        int reserved_block_code;
  58        uint8_t *pattern;
  59};
  60
  61/* Options for the bad block table descriptors */
  62
  63/* The number of bits used per block in the bbt on the device */
  64#define NAND_BBT_NRBITS_MSK     0x0000000F
  65#define NAND_BBT_1BIT           0x00000001
  66#define NAND_BBT_2BIT           0x00000002
  67#define NAND_BBT_4BIT           0x00000004
  68#define NAND_BBT_8BIT           0x00000008
  69/* The bad block table is in the last good block of the device */
  70#define NAND_BBT_LASTBLOCK      0x00000010
  71/* The bbt is at the given page, else we must scan for the bbt */
  72#define NAND_BBT_ABSPAGE        0x00000020
  73/* The bbt is at the given page, else we must scan for the bbt */
  74#define NAND_BBT_SEARCH         0x00000040
  75/* bbt is stored per chip on multichip devices */
  76#define NAND_BBT_PERCHIP        0x00000080
  77/* bbt has a version counter at offset veroffs */
  78#define NAND_BBT_VERSION        0x00000100
  79/* Create a bbt if none axists */
  80#define NAND_BBT_CREATE         0x00000200
  81/* Search good / bad pattern through all pages of a block */
  82#define NAND_BBT_SCANALLPAGES   0x00000400
  83/* Scan block empty during good / bad block scan */
  84#define NAND_BBT_SCANEMPTY      0x00000800
  85/* Write bbt if neccecary */
  86#define NAND_BBT_WRITE          0x00001000
  87/* Read and write back block contents when writing bbt */
  88#define NAND_BBT_SAVECONTENT    0x00002000
  89/* Search good / bad pattern on the first and the second page */
  90#define NAND_BBT_SCAN2NDPAGE    0x00004000
  91
  92/* The maximum number of blocks to scan for a bbt */
  93#define NAND_BBT_SCAN_MAXBLOCKS 4
  94
  95/*
  96 * Constants for oob configuration
  97 */
  98#define ONENAND_BADBLOCK_POS    0
  99
 100/*
 101 * Bad block scanning errors
 102 */
 103#define ONENAND_BBT_READ_ERROR          1
 104#define ONENAND_BBT_READ_ECC_ERROR      2
 105#define ONENAND_BBT_READ_FATAL_ERROR    4
 106
 107/**
 108 * struct bbt_info - [GENERIC] Bad Block Table data structure
 109 * @param bbt_erase_shift       [INTERN] number of address bits in a bbt entry
 110 * @param badblockpos           [INTERN] position of the bad block marker in the oob area
 111 * @param bbt                   [INTERN] bad block table pointer
 112 * @param badblock_pattern      [REPLACEABLE] bad block scan pattern used for initial bad block scan
 113 * @param priv                  [OPTIONAL] pointer to private bbm date
 114 */
 115struct bbm_info {
 116        int bbt_erase_shift;
 117        int badblockpos;
 118        int options;
 119
 120        uint8_t *bbt;
 121
 122        int (*isbad_bbt) (struct mtd_info * mtd, loff_t ofs, int allowbbt);
 123
 124        /* TODO Add more NAND specific fileds */
 125        struct nand_bbt_descr *badblock_pattern;
 126
 127        void *priv;
 128};
 129
 130/* OneNAND BBT interface */
 131extern int onenand_scan_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd);
 132extern int onenand_default_bbt (struct mtd_info *mtd);
 133
 134#endif                          /* __LINUX_MTD_BBM_H */
 135