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 */ 162