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 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License as published by 15 * the Free Software Foundation; either version 2 of the License, or 16 * (at your option) any later version. 17 * 18 * This program is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 * GNU General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License 24 * along with this program; if not, write to the Free Software 25 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 26 * 27 */ 28 #ifndef __LINUX_MTD_BBM_H 29 #define __LINUX_MTD_BBM_H 30 31 /* The maximum number of NAND chips in an array */ 32 #ifndef CONFIG_SYS_NAND_MAX_CHIPS 33 #define CONFIG_SYS_NAND_MAX_CHIPS 1 34 #endif 35 36 /** 37 * struct nand_bbt_descr - bad block table descriptor 38 * @param options options for this descriptor 39 * @param pages the page(s) where we find the bbt, used with 40 * option BBT_ABSPAGE when bbt is searched, 41 * then we store the found bbts pages here. 42 * Its an array and supports up to 8 chips now 43 * @param offs offset of the pattern in the oob area of the page 44 * @param veroffs offset of the bbt version counter in the oob are of the page 45 * @param version version read from the bbt page during scan 46 * @param len length of the pattern, if 0 no pattern check is performed 47 * @param maxblocks maximum number of blocks to search for a bbt. This number of 48 * blocks is reserved at the end of the device 49 * where the tables are written. 50 * @param reserved_block_code if non-0, this pattern denotes a reserved 51 * (rather than bad) block in the stored bbt 52 * @param pattern pattern to identify bad block table or factory marked 53 * good / bad blocks, can be NULL, if len = 0 54 * 55 * Descriptor for the bad block table marker and the descriptor for the 56 * pattern which identifies good and bad blocks. The assumption is made 57 * that the pattern and the version count are always located in the oob area 58 * of the first block. 59 */ 60 struct nand_bbt_descr { 61 int options; 62 int pages[CONFIG_SYS_NAND_MAX_CHIPS]; 63 int offs; 64 int veroffs; 65 uint8_t version[CONFIG_SYS_NAND_MAX_CHIPS]; 66 int len; 67 int maxblocks; 68 int reserved_block_code; 69 uint8_t *pattern; 70 }; 71 72 /* Options for the bad block table descriptors */ 73 74 /* The number of bits used per block in the bbt on the device */ 75 #define NAND_BBT_NRBITS_MSK 0x0000000F 76 #define NAND_BBT_1BIT 0x00000001 77 #define NAND_BBT_2BIT 0x00000002 78 #define NAND_BBT_4BIT 0x00000004 79 #define NAND_BBT_8BIT 0x00000008 80 /* The bad block table is in the last good block of the device */ 81 #define NAND_BBT_LASTBLOCK 0x00000010 82 /* The bbt is at the given page, else we must scan for the bbt */ 83 #define NAND_BBT_ABSPAGE 0x00000020 84 /* bbt is stored per chip on multichip devices */ 85 #define NAND_BBT_PERCHIP 0x00000080 86 /* bbt has a version counter at offset veroffs */ 87 #define NAND_BBT_VERSION 0x00000100 88 /* Create a bbt if none exists */ 89 #define NAND_BBT_CREATE 0x00000200 90 /* 91 * Create an empty BBT with no vendor information. Vendor's information may be 92 * unavailable, for example, if the NAND controller has a different data and OOB 93 * layout or if this information is already purged. Must be used in conjunction 94 * with NAND_BBT_CREATE. 95 */ 96 #define NAND_BBT_CREATE_EMPTY 0x00000400 97 /* Search good / bad pattern through all pages of a block */ 98 #define NAND_BBT_SCANALLPAGES 0x00000800 99 /* Scan block empty during good / bad block scan */ 100 #define NAND_BBT_SCANEMPTY 0x00001000 101 /* Write bbt if neccecary */ 102 #define NAND_BBT_WRITE 0x00002000 103 /* Read and write back block contents when writing bbt */ 104 #define NAND_BBT_SAVECONTENT 0x00004000 105 /* Search good / bad pattern on the first and the second page */ 106 #define NAND_BBT_SCAN2NDPAGE 0x00008000 107 /* Search good / bad pattern on the last page of the eraseblock */ 108 #define NAND_BBT_SCANLASTPAGE 0x00010000 109 /* 110 * Use a flash based bad block table. By default, OOB identifier is saved in 111 * OOB area. This option is passed to the default bad block table function. 112 */ 113 #define NAND_BBT_USE_FLASH 0x00020000 114 /* 115 * Do not store flash based bad block table marker in the OOB area; store it 116 * in-band. 117 */ 118 #define NAND_BBT_NO_OOB 0x00040000 119 /* 120 * Do not write new bad block markers to OOB; useful, e.g., when ECC covers 121 * entire spare area. Must be used with NAND_BBT_USE_FLASH. 122 */ 123 #define NAND_BBT_NO_OOB_BBM 0x00080000 124 125 /* 126 * Flag set by nand_create_default_bbt_descr(), marking that the nand_bbt_descr 127 * was allocated dynamicaly and must be freed in nand_release(). Has no meaning 128 * in nand_chip.bbt_options. 129 */ 130 #define NAND_BBT_DYNAMICSTRUCT 0x80000000 131 132 /* The maximum number of blocks to scan for a bbt */ 133 #define NAND_BBT_SCAN_MAXBLOCKS 4 134 135 /* 136 * Constants for oob configuration 137 */ 138 #define ONENAND_BADBLOCK_POS 0 139 140 /* 141 * Bad block scanning errors 142 */ 143 #define ONENAND_BBT_READ_ERROR 1 144 #define ONENAND_BBT_READ_ECC_ERROR 2 145 #define ONENAND_BBT_READ_FATAL_ERROR 4 146 147 /** 148 * struct bbt_info - [GENERIC] Bad Block Table data structure 149 * @param bbt_erase_shift [INTERN] number of address bits in a bbt entry 150 * @param badblockpos [INTERN] position of the bad block marker in the oob area 151 * @param bbt [INTERN] bad block table pointer 152 * @param badblock_pattern [REPLACEABLE] bad block scan pattern used for initial bad block scan 153 * @param priv [OPTIONAL] pointer to private bbm date 154 */ 155 struct bbm_info { 156 int bbt_erase_shift; 157 int badblockpos; 158 int options; 159 160 uint8_t *bbt; 161 162 int (*isbad_bbt) (struct mtd_info * mtd, loff_t ofs, int allowbbt); 163 164 /* TODO Add more NAND specific fileds */ 165 struct nand_bbt_descr *badblock_pattern; 166 167 void *priv; 168 }; 169 170 /* OneNAND BBT interface */ 171 extern int onenand_scan_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd); 172 extern int onenand_default_bbt (struct mtd_info *mtd); 173 174 #endif /* __LINUX_MTD_BBM_H */ 175