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 */ 162