1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * NAND family Bad Block Management (BBM) header file 4 * - Bad Block Table (BBT) implementation 5 * 6 * Copyright © 2005 Samsung Electronics 7 * Kyungmin Park <kyungmin.park@samsung.com> 8 * 9 * Copyright © 2000-2005 10 * Thomas Gleixner <tglx@linuxtronix.de> 11 */ 12 #ifndef __LINUX_MTD_BBM_H 13 #define __LINUX_MTD_BBM_H 14 15 /* The maximum number of NAND chips in an array */ 16 #define NAND_MAX_CHIPS 8 17 18 /** 19 * struct nand_bbt_descr - bad block table descriptor 20 * @options: options for this descriptor 21 * @pages: the page(s) where we find the bbt, used with option BBT_ABSPAGE 22 * when bbt is searched, then we store the found bbts pages here. 23 * Its an array and supports up to 8 chips now 24 * @offs: offset of the pattern in the oob area of the page 25 * @veroffs: offset of the bbt version counter in the oob are of the page 26 * @version: version read from the bbt page during scan 27 * @len: length of the pattern, if 0 no pattern check is performed 28 * @maxblocks: maximum number of blocks to search for a bbt. This number of 29 * blocks is reserved at the end of the device where the tables are 30 * written. 31 * @reserved_block_code: if non-0, this pattern denotes a reserved (rather than 32 * bad) block in the stored bbt 33 * @pattern: pattern to identify bad block table or factory marked good / 34 * bad blocks, can be NULL, if len = 0 35 * 36 * Descriptor for the bad block table marker and the descriptor for the 37 * pattern which identifies good and bad blocks. The assumption is made 38 * that the pattern and the version count are always located in the oob area 39 * of the first block. 40 */ 41 struct nand_bbt_descr { 42 int options; 43 int pages[NAND_MAX_CHIPS]; 44 int offs; 45 int veroffs; 46 uint8_t version[NAND_MAX_CHIPS]; 47 int len; 48 int maxblocks; 49 int reserved_block_code; 50 uint8_t *pattern; 51 }; 52 53 /* Options for the bad block table descriptors */ 54 55 /* The number of bits used per block in the bbt on the device */ 56 #define NAND_BBT_NRBITS_MSK 0x0000000F 57 #define NAND_BBT_1BIT 0x00000001 58 #define NAND_BBT_2BIT 0x00000002 59 #define NAND_BBT_4BIT 0x00000004 60 #define NAND_BBT_8BIT 0x00000008 61 /* The bad block table is in the last good block of the device */ 62 #define NAND_BBT_LASTBLOCK 0x00000010 63 /* The bbt is at the given page, else we must scan for the bbt */ 64 #define NAND_BBT_ABSPAGE 0x00000020 65 /* bbt is stored per chip on multichip devices */ 66 #define NAND_BBT_PERCHIP 0x00000080 67 /* bbt has a version counter at offset veroffs */ 68 #define NAND_BBT_VERSION 0x00000100 69 /* Create a bbt if none exists */ 70 #define NAND_BBT_CREATE 0x00000200 71 /* 72 * Create an empty BBT with no vendor information. Vendor's information may be 73 * unavailable, for example, if the NAND controller has a different data and OOB 74 * layout or if this information is already purged. Must be used in conjunction 75 * with NAND_BBT_CREATE. 76 */ 77 #define NAND_BBT_CREATE_EMPTY 0x00000400 78 /* Write bbt if neccecary */ 79 #define NAND_BBT_WRITE 0x00002000 80 /* Read and write back block contents when writing bbt */ 81 #define NAND_BBT_SAVECONTENT 0x00004000 82 83 /* 84 * Use a flash based bad block table. By default, OOB identifier is saved in 85 * OOB area. This option is passed to the default bad block table function. 86 */ 87 #define NAND_BBT_USE_FLASH 0x00020000 88 /* 89 * Do not store flash based bad block table marker in the OOB area; store it 90 * in-band. 91 */ 92 #define NAND_BBT_NO_OOB 0x00040000 93 /* 94 * Do not write new bad block markers to OOB; useful, e.g., when ECC covers 95 * entire spare area. Must be used with NAND_BBT_USE_FLASH. 96 */ 97 #define NAND_BBT_NO_OOB_BBM 0x00080000 98 99 /* 100 * Flag set by nand_create_default_bbt_descr(), marking that the nand_bbt_descr 101 * was allocated dynamicaly and must be freed in nand_release(). Has no meaning 102 * in nand_chip.bbt_options. 103 */ 104 #define NAND_BBT_DYNAMICSTRUCT 0x80000000 105 106 /* The maximum number of blocks to scan for a bbt */ 107 #define NAND_BBT_SCAN_MAXBLOCKS 4 108 109 /* 110 * Bad block scanning errors 111 */ 112 #define ONENAND_BBT_READ_ERROR 1 113 #define ONENAND_BBT_READ_ECC_ERROR 2 114 #define ONENAND_BBT_READ_FATAL_ERROR 4 115 116 /** 117 * struct bbm_info - [GENERIC] Bad Block Table data structure 118 * @bbt_erase_shift: [INTERN] number of address bits in a bbt entry 119 * @options: options for this descriptor 120 * @bbt: [INTERN] bad block table pointer 121 * @isbad_bbt: function to determine if a block is bad 122 * @badblock_pattern: [REPLACEABLE] bad block scan pattern used for 123 * initial bad block scan 124 * @priv: [OPTIONAL] pointer to private bbm date 125 */ 126 struct bbm_info { 127 int bbt_erase_shift; 128 int options; 129 130 uint8_t *bbt; 131 132 int (*isbad_bbt)(struct mtd_info *mtd, loff_t ofs, int allowbbt); 133 134 /* TODO Add more NAND specific fileds */ 135 struct nand_bbt_descr *badblock_pattern; 136 137 void *priv; 138 }; 139 140 /* OneNAND BBT interface */ 141 extern int onenand_default_bbt(struct mtd_info *mtd); 142 143 #endif /* __LINUX_MTD_BBM_H */ 144
