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 © 2005 Samsung Electronics 8 * Kyungmin Park <kyungmin.park@samsung.com> 9 * 10 * Copyright © 2000-2005 11 * Thomas Gleixner <tglx@linuxtronix.de> 12 * 13 * SPDX-License-Identifier: GPL-2.0+ 14 * 15 */ 16 #ifndef __LINUX_MTD_BBM_H 17 #define __LINUX_MTD_BBM_H 18 19 /* The maximum number of NAND chips in an array */ 20 #ifndef CONFIG_SYS_NAND_MAX_CHIPS 21 #define CONFIG_SYS_NAND_MAX_CHIPS 1 22 #endif 23 24 /** 25 * struct nand_bbt_descr - bad block table descriptor 26 * @options: options for this descriptor 27 * @pages: the page(s) where we find the bbt, used with option BBT_ABSPAGE 28 * when bbt is searched, then we store the found bbts pages here. 29 * Its an array and supports up to 8 chips now 30 * @offs: offset of the pattern in the oob area of the page 31 * @veroffs: offset of the bbt version counter in the oob are of the page 32 * @version: version read from the bbt page during scan 33 * @len: length of the pattern, if 0 no pattern check is performed 34 * @maxblocks: maximum number of blocks to search for a bbt. This number of 35 * blocks is reserved at the end of the device where the tables are 36 * written. 37 * @reserved_block_code: if non-0, this pattern denotes a reserved (rather than 38 * bad) block in the stored bbt 39 * @pattern: pattern to identify bad block table or factory marked good / 40 * 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 /* Write bbt if neccecary */ 85 #define NAND_BBT_WRITE 0x00002000 86 /* Read and write back block contents when writing bbt */ 87 #define NAND_BBT_SAVECONTENT 0x00004000 88 /* Search good / bad pattern on the first and the second page */ 89 #define NAND_BBT_SCAN2NDPAGE 0x00008000 90 /* Search good / bad pattern on the last page of the eraseblock */ 91 #define NAND_BBT_SCANLASTPAGE 0x00010000 92 /* 93 * Use a flash based bad block table. By default, OOB identifier is saved in 94 * OOB area. This option is passed to the default bad block table function. 95 */ 96 #define NAND_BBT_USE_FLASH 0x00020000 97 /* 98 * Do not store flash based bad block table marker in the OOB area; store it 99 * in-band. 100 */ 101 #define NAND_BBT_NO_OOB 0x00040000 102 /* 103 * Do not write new bad block markers to OOB; useful, e.g., when ECC covers 104 * entire spare area. Must be used with NAND_BBT_USE_FLASH. 105 */ 106 #define NAND_BBT_NO_OOB_BBM 0x00080000 107 108 /* 109 * Flag set by nand_create_default_bbt_descr(), marking that the nand_bbt_descr 110 * was allocated dynamicaly and must be freed in nand_release(). Has no meaning 111 * in nand_chip.bbt_options. 112 */ 113 #define NAND_BBT_DYNAMICSTRUCT 0x80000000 114 115 /* The maximum number of blocks to scan for a bbt */ 116 #define NAND_BBT_SCAN_MAXBLOCKS 4 117 118 /* 119 * Constants for oob configuration 120 */ 121 #define NAND_SMALL_BADBLOCK_POS 5 122 #define NAND_LARGE_BADBLOCK_POS 0 123 #define ONENAND_BADBLOCK_POS 0 124 125 /* 126 * Bad block scanning errors 127 */ 128 #define ONENAND_BBT_READ_ERROR 1 129 #define ONENAND_BBT_READ_ECC_ERROR 2 130 #define ONENAND_BBT_READ_FATAL_ERROR 4 131 132 /** 133 * struct bbm_info - [GENERIC] Bad Block Table data structure 134 * @bbt_erase_shift: [INTERN] number of address bits in a bbt entry 135 * @badblockpos: [INTERN] position of the bad block marker in the oob area 136 * @options: options for this descriptor 137 * @bbt: [INTERN] bad block table pointer 138 * @isbad_bbt: function to determine if a block is bad 139 * @badblock_pattern: [REPLACEABLE] bad block scan pattern used for 140 * initial bad block scan 141 * @priv: [OPTIONAL] pointer to private bbm date 142 */ 143 struct bbm_info { 144 int bbt_erase_shift; 145 int badblockpos; 146 int options; 147 148 uint8_t *bbt; 149 150 int (*isbad_bbt)(struct mtd_info *mtd, loff_t ofs, int allowbbt); 151 152 /* TODO Add more NAND specific fileds */ 153 struct nand_bbt_descr *badblock_pattern; 154 155 void *priv; 156 }; 157 158 /* OneNAND BBT interface */ 159 extern int onenand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd); 160 extern int onenand_default_bbt(struct mtd_info *mtd); 161 162 #endif /* __LINUX_MTD_BBM_H */ 163