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  * SPDX-License-Identifier:     GPL-2.0+
  14  */
  15 #ifndef __LINUX_MTD_BBM_H
  16 #define __LINUX_MTD_BBM_H
  17
  18 /* The maximum number of NAND chips in an array */
  19 #ifndef CONFIG_SYS_NAND_MAX_CHIPS
  20 #define CONFIG_SYS_NAND_MAX_CHIPS       1
  21 #endif
  22
  23 /**
  24  * struct nand_bbt_descr - bad block table descriptor
  25  * @param options       options for this descriptor
  26  * @param pages         the page(s) where we find the bbt, used with
  27  *                      option BBT_ABSPAGE when bbt is searched,
  28  *                      then we store the found bbts pages here.
  29  *                      Its an array and supports up to 8 chips now
  30  * @param offs          offset of the pattern in the oob area of the page
  31  * @param veroffs       offset of the bbt version counter in the oob are of the page
  32  * @param version       version read from the bbt page during scan
  33  * @param len           length of the pattern, if 0 no pattern check is performed
  34  * @param maxblocks     maximum number of blocks to search for a bbt. This number of
  35  *                      blocks is reserved at the end of the device
  36  *                      where the tables are written.
  37  * @param reserved_block_code   if non-0, this pattern denotes a reserved
  38  *                      (rather than bad) block in the stored bbt
  39  * @param pattern       pattern to identify bad block table or factory marked
  40  *                      good / bad blocks, can be NULL, if len = 0
  41  *
  42  * Descriptor for the bad block table marker and the descriptor for the
  43  * pattern which identifies good and bad blocks. The assumption is made
  44  * that the pattern and the version count are always located in the oob area
  45  * of the first block.
  46  */
  47 struct nand_bbt_descr {
  48         int options;
  49         int pages[CONFIG_SYS_NAND_MAX_CHIPS];
  50         int offs;
  51         int veroffs;
  52         uint8_t version[CONFIG_SYS_NAND_MAX_CHIPS];
  53         int len;
  54         int maxblocks;
  55         int reserved_block_code;
  56         uint8_t *pattern;
  57 };
  58
  59 /* Options for the bad block table descriptors */
  60
  61 /* The number of bits used per block in the bbt on the device */
  62 #define NAND_BBT_NRBITS_MSK     0x0000000F
  63 #define NAND_BBT_1BIT           0x00000001
  64 #define NAND_BBT_2BIT           0x00000002
  65 #define NAND_BBT_4BIT           0x00000004
  66 #define NAND_BBT_8BIT           0x00000008
  67 /* The bad block table is in the last good block of the device */
  68 #define NAND_BBT_LASTBLOCK      0x00000010
  69 /* The bbt is at the given page, else we must scan for the bbt */
  70 #define NAND_BBT_ABSPAGE        0x00000020
  71 /* bbt is stored per chip on multichip devices */
  72 #define NAND_BBT_PERCHIP        0x00000080
  73 /* bbt has a version counter at offset veroffs */
  74 #define NAND_BBT_VERSION        0x00000100
  75 /* Create a bbt if none exists */
  76 #define NAND_BBT_CREATE         0x00000200
  77 /*
  78  * Create an empty BBT with no vendor information. Vendor's information may be
  79  * unavailable, for example, if the NAND controller has a different data and OOB
  80  * layout or if this information is already purged. Must be used in conjunction
  81  * with NAND_BBT_CREATE.
  82  */
  83 #define NAND_BBT_CREATE_EMPTY   0x00000400
  84 /* Search good / bad pattern through all pages of a block */
  85 #define NAND_BBT_SCANALLPAGES   0x00000800
  86 /* Scan block empty during good / bad block scan */
  87 #define NAND_BBT_SCANEMPTY      0x00001000
  88 /* Write bbt if neccecary */
  89 #define NAND_BBT_WRITE          0x00002000
  90 /* Read and write back block contents when writing bbt */
  91 #define NAND_BBT_SAVECONTENT    0x00004000
  92 /* Search good / bad pattern on the first and the second page */
  93 #define NAND_BBT_SCAN2NDPAGE    0x00008000
  94 /* Search good / bad pattern on the last page of the eraseblock */
  95 #define NAND_BBT_SCANLASTPAGE   0x00010000
  96 /*
  97  * Use a flash based bad block table. By default, OOB identifier is saved in
  98  * OOB area. This option is passed to the default bad block table function.
  99  */
 100 #define NAND_BBT_USE_FLASH      0x00020000
 101 /*
 102  * Do not store flash based bad block table marker in the OOB area; store it
 103  * in-band.
 104  */
 105 #define NAND_BBT_NO_OOB         0x00040000
 106 /*
 107  * Do not write new bad block markers to OOB; useful, e.g., when ECC covers
 108  * entire spare area. Must be used with NAND_BBT_USE_FLASH.
 109  */
 110 #define NAND_BBT_NO_OOB_BBM     0x00080000
 111
 112 /*
 113  * Flag set by nand_create_default_bbt_descr(), marking that the nand_bbt_descr
 114  * was allocated dynamicaly and must be freed in nand_release(). Has no meaning
 115  * in nand_chip.bbt_options.
 116  */
 117 #define NAND_BBT_DYNAMICSTRUCT  0x80000000
 118
 119 /* The maximum number of blocks to scan for a bbt */
 120 #define NAND_BBT_SCAN_MAXBLOCKS 4
 121
 122 /*
 123  * Constants for oob configuration
 124  */
 125 #define ONENAND_BADBLOCK_POS    0
 126
 127 /*
 128  * Bad block scanning errors
 129  */
 130 #define ONENAND_BBT_READ_ERROR          1
 131 #define ONENAND_BBT_READ_ECC_ERROR      2
 132 #define ONENAND_BBT_READ_FATAL_ERROR    4
 133
 134 /**
 135  * struct bbt_info - [GENERIC] Bad Block Table data structure
 136  * @param bbt_erase_shift       [INTERN] number of address bits in a bbt entry
 137  * @param badblockpos           [INTERN] position of the bad block marker in the oob area
 138  * @param bbt                   [INTERN] bad block table pointer
 139  * @param badblock_pattern      [REPLACEABLE] bad block scan pattern used for initial bad block scan
 140  * @param priv                  [OPTIONAL] pointer to private bbm date
 141  */
 142 struct bbm_info {
 143         int bbt_erase_shift;
 144         int badblockpos;
 145         int options;
 146
 147         uint8_t *bbt;
 148
 149         int (*isbad_bbt) (struct mtd_info * mtd, loff_t ofs, int allowbbt);
 150
 151         /* TODO Add more NAND specific fileds */
 152         struct nand_bbt_descr *badblock_pattern;
 153
 154         void *priv;
 155 };
 156
 157 /* OneNAND BBT interface */
 158 extern int onenand_scan_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd);
 159 extern int onenand_default_bbt (struct mtd_info *mtd);
 160
 161 #endif                          /* __LINUX_MTD_BBM_H */