1/* 2 * NAND family Bad Block Management (BBM) header file 3 * - Bad Block Table (BBT) implementation 4 * 5 * Copyright © 2005 Samsung Electronics 6 * Kyungmin Park <kyungmin.park@samsung.com> 7 * 8 * Copyright © 2000-2005 9 * Thomas Gleixner <tglx@linuxtronix.de> 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 24 * 25 */ 26#ifndef __LINUX_MTD_BBM_H 27#define __LINUX_MTD_BBM_H 28 29/* The maximum number of NAND chips in an array */ 30#define NAND_MAX_CHIPS 8 31 32/** 33 * struct nand_bbt_descr - bad block table descriptor 34 * @options: options for this descriptor 35 * @pages: the page(s) where we find the bbt, used with option BBT_ABSPAGE 36 * when bbt is searched, then we store the found bbts pages here. 37 * Its an array and supports up to 8 chips now 38 * @offs: offset of the pattern in the oob area of the page 39 * @veroffs: offset of the bbt version counter in the oob are of the page 40 * @version: version read from the bbt page during scan 41 * @len: length of the pattern, if 0 no pattern check is performed 42 * @maxblocks: maximum number of blocks to search for a bbt. This number of 43 * blocks is reserved at the end of the device where the tables are 44 * written. 45 * @reserved_block_code: if non-0, this pattern denotes a reserved (rather than 46 * bad) block in the stored bbt 47 * @pattern: pattern to identify bad block table or factory marked good / 48 * bad blocks, can be NULL, if len = 0 49 * 50 * Descriptor for the bad block table marker and the descriptor for the 51 * pattern which identifies good and bad blocks. The assumption is made 52 * that the pattern and the version count are always located in the oob area 53 * of the first block. 54 */ 55struct nand_bbt_descr { 56 int options; 57 int pages[NAND_MAX_CHIPS]; 58 int offs; 59 int veroffs; 60 uint8_t version[NAND_MAX_CHIPS]; 61 int len; 62 int maxblocks; 63 int reserved_block_code; 64 uint8_t *pattern; 65}; 66 67/* Options for the bad block table descriptors */ 68 69/* The number of bits used per block in the bbt on the device */ 70#define NAND_BBT_NRBITS_MSK 0x0000000F 71#define NAND_BBT_1BIT 0x00000001 72#define NAND_BBT_2BIT 0x00000002 73#define NAND_BBT_4BIT 0x00000004 74#define NAND_BBT_8BIT 0x00000008 75/* The bad block table is in the last good block of the device */ 76#define NAND_BBT_LASTBLOCK 0x00000010 77/* The bbt is at the given page, else we must scan for the bbt */ 78#define NAND_BBT_ABSPAGE 0x00000020 79/* bbt is stored per chip on multichip devices */ 80#define NAND_BBT_PERCHIP 0x00000080 81/* bbt has a version counter at offset veroffs */ 82#define NAND_BBT_VERSION 0x00000100 83/* Create a bbt if none exists */ 84#define NAND_BBT_CREATE 0x00000200 85/* 86 * Create an empty BBT with no vendor information. Vendor's information may be 87 * unavailable, for example, if the NAND controller has a different data and OOB 88 * layout or if this information is already purged. Must be used in conjunction 89 * with NAND_BBT_CREATE. 90 */ 91#define NAND_BBT_CREATE_EMPTY 0x00000400 92/* Write bbt if neccecary */ 93#define NAND_BBT_WRITE 0x00002000 94/* Read and write back block contents when writing bbt */ 95#define NAND_BBT_SAVECONTENT 0x00004000 96/* Search good / bad pattern on the first and the second page */ 97#define NAND_BBT_SCAN2NDPAGE 0x00008000 98/* Search good / bad pattern on the last page of the eraseblock */ 99#define NAND_BBT_SCANLASTPAGE 0x00010000 100/* 101 * Use a flash based bad block table. By default, OOB identifier is saved in 102 * OOB area. This option is passed to the default bad block table function. 103 */ 104#define NAND_BBT_USE_FLASH 0x00020000 105/* 106 * Do not store flash based bad block table marker in the OOB area; store it 107 * in-band. 108 */ 109#define NAND_BBT_NO_OOB 0x00040000 110/* 111 * Do not write new bad block markers to OOB; useful, e.g., when ECC covers 112 * entire spare area. Must be used with NAND_BBT_USE_FLASH. 113 */ 114#define NAND_BBT_NO_OOB_BBM 0x00080000 115 116/* 117 * Flag set by nand_create_default_bbt_descr(), marking that the nand_bbt_descr 118 * was allocated dynamicaly and must be freed in nand_release(). Has no meaning 119 * in nand_chip.bbt_options. 120 */ 121#define NAND_BBT_DYNAMICSTRUCT 0x80000000 122 123/* The maximum number of blocks to scan for a bbt */ 124#define NAND_BBT_SCAN_MAXBLOCKS 4 125 126/* 127 * Constants for oob configuration 128 */ 129#define NAND_SMALL_BADBLOCK_POS 5 130#define NAND_LARGE_BADBLOCK_POS 0 131#define ONENAND_BADBLOCK_POS 0 132 133/* 134 * Bad block scanning errors 135 */ 136#define ONENAND_BBT_READ_ERROR 1 137#define ONENAND_BBT_READ_ECC_ERROR 2 138#define ONENAND_BBT_READ_FATAL_ERROR 4 139 140/** 141 * struct bbm_info - [GENERIC] Bad Block Table data structure 142 * @bbt_erase_shift: [INTERN] number of address bits in a bbt entry 143 * @badblockpos: [INTERN] position of the bad block marker in the oob area 144 * @options: options for this descriptor 145 * @bbt: [INTERN] bad block table pointer 146 * @isbad_bbt: function to determine if a block is bad 147 * @badblock_pattern: [REPLACEABLE] bad block scan pattern used for 148 * initial bad block scan 149 * @priv: [OPTIONAL] pointer to private bbm date 150 */ 151struct bbm_info { 152 int bbt_erase_shift; 153 int badblockpos; 154 int options; 155 156 uint8_t *bbt; 157 158 int (*isbad_bbt)(struct mtd_info *mtd, loff_t ofs, int allowbbt); 159 160 /* TODO Add more NAND specific fileds */ 161 struct nand_bbt_descr *badblock_pattern; 162 163 void *priv; 164}; 165 166/* OneNAND BBT interface */ 167extern int onenand_default_bbt(struct mtd_info *mtd); 168 169#endif /* __LINUX_MTD_BBM_H */ 170