include/linux/mtd/bbm.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  *  linux/include/linux/mtd/bbm.h
   4  *
   5  *  NAND family Bad Block Management (BBM) header file
   6  *    - Bad Block Table (BBT) implementation
   7  *
   8  *  Copyright © 2005 Samsung Electronics
   9  *  Kyungmin Park <kyungmin.park@samsung.com>
  10  *
  11  *  Copyright © 2000-2005
  12  *  Thomas Gleixner <tglx@linuxtronix.de>
  13  *
  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  * @options:    options for this descriptor
  26  * @pages:      the page(s) where we find the bbt, used with option BBT_ABSPAGE
  27  *              when bbt is searched, then we store the found bbts pages here.
  28  *              Its an array and supports up to 8 chips now
  29  * @offs:       offset of the pattern in the oob area of the page
  30  * @veroffs:    offset of the bbt version counter in the oob are of the page
  31  * @version:    version read from the bbt page during scan
  32  * @len:        length of the pattern, if 0 no pattern check is performed
  33  * @maxblocks:  maximum number of blocks to search for a bbt. This number of
  34  *              blocks is reserved at the end of the device where the tables are
  35  *              written.
  36  * @reserved_block_code: if non-0, this pattern denotes a reserved (rather than
  37  *              bad) block in the stored bbt
  38  * @pattern:    pattern to identify bad block table or factory marked good /
  39  *              bad blocks, can be NULL, if len = 0
  40  *
  41  * Descriptor for the bad block table marker and the descriptor for the
  42  * pattern which identifies good and bad blocks. The assumption is made
  43  * that the pattern and the version count are always located in the oob area
  44  * of the first block.
  45  */
  46 struct nand_bbt_descr {
  47         int options;
  48         int pages[CONFIG_SYS_NAND_MAX_CHIPS];
  49         int offs;
  50         int veroffs;
  51         uint8_t version[CONFIG_SYS_NAND_MAX_CHIPS];
  52         int len;
  53         int maxblocks;
  54         int reserved_block_code;
  55         uint8_t *pattern;
  56 };
  57
  58 /* Options for the bad block table descriptors */
  59
  60 /* The number of bits used per block in the bbt on the device */
  61 #define NAND_BBT_NRBITS_MSK     0x0000000F
  62 #define NAND_BBT_1BIT           0x00000001
  63 #define NAND_BBT_2BIT           0x00000002
  64 #define NAND_BBT_4BIT           0x00000004
  65 #define NAND_BBT_8BIT           0x00000008
  66 /* The bad block table is in the last good block of the device */
  67 #define NAND_BBT_LASTBLOCK      0x00000010
  68 /* The bbt is at the given page, else we must scan for the bbt */
  69 #define NAND_BBT_ABSPAGE        0x00000020
  70 /* bbt is stored per chip on multichip devices */
  71 #define NAND_BBT_PERCHIP        0x00000080
  72 /* bbt has a version counter at offset veroffs */
  73 #define NAND_BBT_VERSION        0x00000100
  74 /* Create a bbt if none exists */
  75 #define NAND_BBT_CREATE         0x00000200
  76 /*
  77  * Create an empty BBT with no vendor information. Vendor's information may be
  78  * unavailable, for example, if the NAND controller has a different data and OOB
  79  * layout or if this information is already purged. Must be used in conjunction
  80  * with NAND_BBT_CREATE.
  81  */
  82 #define NAND_BBT_CREATE_EMPTY   0x00000400
  83 /* Write bbt if neccecary */
  84 #define NAND_BBT_WRITE          0x00002000
  85 /* Read and write back block contents when writing bbt */
  86 #define NAND_BBT_SAVECONTENT    0x00004000
  87 /* Search good / bad pattern on the first and the second page */
  88 #define NAND_BBT_SCAN2NDPAGE    0x00008000
  89 /* Search good / bad pattern on the last page of the eraseblock */
  90 #define NAND_BBT_SCANLASTPAGE   0x00010000
  91 /*
  92  * Use a flash based bad block table. By default, OOB identifier is saved in
  93  * OOB area. This option is passed to the default bad block table function.
  94  */
  95 #define NAND_BBT_USE_FLASH      0x00020000
  96 /*
  97  * Do not store flash based bad block table marker in the OOB area; store it
  98  * in-band.
  99  */
 100 #define NAND_BBT_NO_OOB         0x00040000
 101 /*
 102  * Do not write new bad block markers to OOB; useful, e.g., when ECC covers
 103  * entire spare area. Must be used with NAND_BBT_USE_FLASH.
 104  */
 105 #define NAND_BBT_NO_OOB_BBM     0x00080000
 106
 107 /*
 108  * Flag set by nand_create_default_bbt_descr(), marking that the nand_bbt_descr
 109  * was allocated dynamicaly and must be freed in nand_release(). Has no meaning
 110  * in nand_chip.bbt_options.
 111  */
 112 #define NAND_BBT_DYNAMICSTRUCT  0x80000000
 113
 114 /* The maximum number of blocks to scan for a bbt */
 115 #define NAND_BBT_SCAN_MAXBLOCKS 4
 116
 117 /*
 118  * Constants for oob configuration
 119  */
 120 #define NAND_SMALL_BADBLOCK_POS         5
 121 #define NAND_LARGE_BADBLOCK_POS         0
 122 #define ONENAND_BADBLOCK_POS            0
 123
 124 /*
 125  * Bad block scanning errors
 126  */
 127 #define ONENAND_BBT_READ_ERROR          1
 128 #define ONENAND_BBT_READ_ECC_ERROR      2
 129 #define ONENAND_BBT_READ_FATAL_ERROR    4
 130
 131 /**
 132  * struct bbm_info - [GENERIC] Bad Block Table data structure
 133  * @bbt_erase_shift:    [INTERN] number of address bits in a bbt entry
 134  * @badblockpos:        [INTERN] position of the bad block marker in the oob area
 135  * @options:            options for this descriptor
 136  * @bbt:                [INTERN] bad block table pointer
 137  * @isbad_bbt:          function to determine if a block is bad
 138  * @badblock_pattern:   [REPLACEABLE] bad block scan pattern used for
 139  *                      initial bad block scan
 140  * @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 */