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 as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  26  *
  27  */
  28 #ifndef __LINUX_MTD_BBM_H
  29 #define __LINUX_MTD_BBM_H
  30
  31 /* The maximum number of NAND chips in an array */
  32 #ifndef CONFIG_SYS_NAND_MAX_CHIPS
  33 #define CONFIG_SYS_NAND_MAX_CHIPS       1
  34 #endif
  35
  36 /**
  37  * struct nand_bbt_descr - bad block table descriptor
  38  * @param options       options for this descriptor
  39  * @param pages         the page(s) where we find the bbt, used with
  40  *                      option BBT_ABSPAGE when bbt is searched,
  41  *                      then we store the found bbts pages here.
  42  *                      Its an array and supports up to 8 chips now
  43  * @param offs          offset of the pattern in the oob area of the page
  44  * @param veroffs       offset of the bbt version counter in the oob are of the page
  45  * @param version       version read from the bbt page during scan
  46  * @param len           length of the pattern, if 0 no pattern check is performed
  47  * @param maxblocks     maximum number of blocks to search for a bbt. This number of
  48  *                      blocks is reserved at the end of the device
  49  *                      where the tables are written.
  50  * @param reserved_block_code   if non-0, this pattern denotes a reserved
  51  *                      (rather than bad) block in the stored bbt
  52  * @param pattern       pattern to identify bad block table or factory marked
  53  *                      good / bad blocks, can be NULL, if len = 0
  54  *
  55  * Descriptor for the bad block table marker and the descriptor for the
  56  * pattern which identifies good and bad blocks. The assumption is made
  57  * that the pattern and the version count are always located in the oob area
  58  * of the first block.
  59  */
  60 struct nand_bbt_descr {
  61         int options;
  62         int pages[CONFIG_SYS_NAND_MAX_CHIPS];
  63         int offs;
  64         int veroffs;
  65         uint8_t version[CONFIG_SYS_NAND_MAX_CHIPS];
  66         int len;
  67         int maxblocks;
  68         int reserved_block_code;
  69         uint8_t *pattern;
  70 };
  71
  72 /* Options for the bad block table descriptors */
  73
  74 /* The number of bits used per block in the bbt on the device */
  75 #define NAND_BBT_NRBITS_MSK     0x0000000F
  76 #define NAND_BBT_1BIT           0x00000001
  77 #define NAND_BBT_2BIT           0x00000002
  78 #define NAND_BBT_4BIT           0x00000004
  79 #define NAND_BBT_8BIT           0x00000008
  80 /* The bad block table is in the last good block of the device */
  81 #define NAND_BBT_LASTBLOCK      0x00000010
  82 /* The bbt is at the given page, else we must scan for the bbt */
  83 #define NAND_BBT_ABSPAGE        0x00000020
  84 /* The bbt is at the given page, else we must scan for the bbt */
  85 #define NAND_BBT_SEARCH         0x00000040
  86 /* bbt is stored per chip on multichip devices */
  87 #define NAND_BBT_PERCHIP        0x00000080
  88 /* bbt has a version counter at offset veroffs */
  89 #define NAND_BBT_VERSION        0x00000100
  90 /* Create a bbt if none exists */
  91 #define NAND_BBT_CREATE         0x00000200
  92 /* Search good / bad pattern through all pages of a block */
  93 #define NAND_BBT_SCANALLPAGES   0x00000400
  94 /* Scan block empty during good / bad block scan */
  95 #define NAND_BBT_SCANEMPTY      0x00000800
  96 /* Write bbt if neccecary */
  97 #define NAND_BBT_WRITE          0x00001000
  98 /* Read and write back block contents when writing bbt */
  99 #define NAND_BBT_SAVECONTENT    0x00002000
 100 /* Search good / bad pattern on the first and the second page */
 101 #define NAND_BBT_SCAN2NDPAGE    0x00004000
 102 /* Search good / bad pattern on the last page of the eraseblock */
 103 #define NAND_BBT_SCANLASTPAGE   0x00008000
 104 /* Chip stores bad block marker on BOTH 1st and 6th bytes of OOB */
 105 #define NAND_BBT_SCANBYTE1AND6 0x00100000
 106 /* The nand_bbt_descr was created dynamicaly and must be freed */
 107 #define NAND_BBT_DYNAMICSTRUCT 0x00200000
 108 /* The bad block table does not OOB for marker */
 109 #define NAND_BBT_NO_OOB         0x00400000
 110
 111 /* The maximum number of blocks to scan for a bbt */
 112 #define NAND_BBT_SCAN_MAXBLOCKS 4
 113
 114 /*
 115  * Constants for oob configuration
 116  */
 117 #define ONENAND_BADBLOCK_POS    0
 118
 119 /*
 120  * Bad block scanning errors
 121  */
 122 #define ONENAND_BBT_READ_ERROR          1
 123 #define ONENAND_BBT_READ_ECC_ERROR      2
 124 #define ONENAND_BBT_READ_FATAL_ERROR    4
 125
 126 /**
 127  * struct bbt_info - [GENERIC] Bad Block Table data structure
 128  * @param bbt_erase_shift       [INTERN] number of address bits in a bbt entry
 129  * @param badblockpos           [INTERN] position of the bad block marker in the oob area
 130  * @param bbt                   [INTERN] bad block table pointer
 131  * @param badblock_pattern      [REPLACEABLE] bad block scan pattern used for initial bad block scan
 132  * @param priv                  [OPTIONAL] pointer to private bbm date
 133  */
 134 struct bbm_info {
 135         int bbt_erase_shift;
 136         int badblockpos;
 137         int options;
 138
 139         uint8_t *bbt;
 140
 141         int (*isbad_bbt) (struct mtd_info * mtd, loff_t ofs, int allowbbt);
 142
 143         /* TODO Add more NAND specific fileds */
 144         struct nand_bbt_descr *badblock_pattern;
 145
 146         void *priv;
 147 };
 148
 149 /* OneNAND BBT interface */
 150 extern int onenand_scan_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd);
 151 extern int onenand_default_bbt (struct mtd_info *mtd);
 152
 153 #endif                          /* __LINUX_MTD_BBM_H */