Edit File: bbm.h
/* * linux/include/linux/mtd/bbm.h * * NAND family Bad Block Management (BBM) header file * - Bad Block Table (BBT) implementation * * Copyright © 2005 Samsung Electronics * Kyungmin Park <kyungmin.park@samsung.com> * * Copyright © 2000-2005 * Thomas Gleixner <tglx@linuxtronix.de> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * */ #ifndef __LINUX_MTD_BBM_H #define __LINUX_MTD_BBM_H /* The maximum number of NAND chips in an array */ #define NAND_MAX_CHIPS 8 /** * struct nand_bbt_descr - bad block table descriptor * @options: options for this descriptor * @pages: the page(s) where we find the bbt, used with option BBT_ABSPAGE * when bbt is searched, then we store the found bbts pages here. * Its an array and supports up to 8 chips now * @offs: offset of the pattern in the oob area of the page * @veroffs: offset of the bbt version counter in the oob are of the page * @version: version read from the bbt page during scan * @len: length of the pattern, if 0 no pattern check is performed * @maxblocks: maximum number of blocks to search for a bbt. This number of * blocks is reserved at the end of the device where the tables are * written. * @reserved_block_code: if non-0, this pattern denotes a reserved (rather than * bad) block in the stored bbt * @pattern: pattern to identify bad block table or factory marked good / * bad blocks, can be NULL, if len = 0 * * Descriptor for the bad block table marker and the descriptor for the * pattern which identifies good and bad blocks. The assumption is made * that the pattern and the version count are always located in the oob area * of the first block. */ struct nand_bbt_descr { int options; int pages[NAND_MAX_CHIPS]; int offs; int veroffs; uint8_t version[NAND_MAX_CHIPS]; int len; int maxblocks; int reserved_block_code; uint8_t *pattern; }; /* Options for the bad block table descriptors */ /* The number of bits used per block in the bbt on the device */ #define NAND_BBT_NRBITS_MSK 0x0000000F #define NAND_BBT_1BIT 0x00000001 #define NAND_BBT_2BIT 0x00000002 #define NAND_BBT_4BIT 0x00000004 #define NAND_BBT_8BIT 0x00000008 /* The bad block table is in the last good block of the device */ #define NAND_BBT_LASTBLOCK 0x00000010 /* The bbt is at the given page, else we must scan for the bbt */ #define NAND_BBT_ABSPAGE 0x00000020 /* bbt is stored per chip on multichip devices */ #define NAND_BBT_PERCHIP 0x00000080 /* bbt has a version counter at offset veroffs */ #define NAND_BBT_VERSION 0x00000100 /* Create a bbt if none exists */ #define NAND_BBT_CREATE 0x00000200 /* * Create an empty BBT with no vendor information. Vendor's information may be * unavailable, for example, if the NAND controller has a different data and OOB * layout or if this information is already purged. Must be used in conjunction * with NAND_BBT_CREATE. */ #define NAND_BBT_CREATE_EMPTY 0x00000400 /* Search good / bad pattern through all pages of a block */ #define NAND_BBT_SCANALLPAGES 0x00000800 /* Scan block empty during good / bad block scan */ #define NAND_BBT_SCANEMPTY 0x00001000 /* Write bbt if neccecary */ #define NAND_BBT_WRITE 0x00002000 /* Read and write back block contents when writing bbt */ #define NAND_BBT_SAVECONTENT 0x00004000 /* Search good / bad pattern on the first and the second page */ #define NAND_BBT_SCAN2NDPAGE 0x00008000 /* Search good / bad pattern on the last page of the eraseblock */ #define NAND_BBT_SCANLASTPAGE 0x00010000 /* * Use a flash based bad block table. By default, OOB identifier is saved in * OOB area. This option is passed to the default bad block table function. */ #define NAND_BBT_USE_FLASH 0x00020000 /* * Do not store flash based bad block table marker in the OOB area; store it * in-band. */ #define NAND_BBT_NO_OOB 0x00040000 /* * Do not write new bad block markers to OOB; useful, e.g., when ECC covers * entire spare area. Must be used with NAND_BBT_USE_FLASH. */ #define NAND_BBT_NO_OOB_BBM 0x00080000 /* * Flag set by nand_create_default_bbt_descr(), marking that the nand_bbt_descr * was allocated dynamicaly and must be freed in nand_release(). Has no meaning * in nand_chip.bbt_options. */ #define NAND_BBT_DYNAMICSTRUCT 0x80000000 /* The maximum number of blocks to scan for a bbt */ #define NAND_BBT_SCAN_MAXBLOCKS 4 /* * Constants for oob configuration */ #define NAND_SMALL_BADBLOCK_POS 5 #define NAND_LARGE_BADBLOCK_POS 0 #define ONENAND_BADBLOCK_POS 0 /* * Bad block scanning errors */ #define ONENAND_BBT_READ_ERROR 1 #define ONENAND_BBT_READ_ECC_ERROR 2 #define ONENAND_BBT_READ_FATAL_ERROR 4 /** * struct bbm_info - [GENERIC] Bad Block Table data structure * @bbt_erase_shift: [INTERN] number of address bits in a bbt entry * @badblockpos: [INTERN] position of the bad block marker in the oob area * @options: options for this descriptor * @bbt: [INTERN] bad block table pointer * @isbad_bbt: function to determine if a block is bad * @badblock_pattern: [REPLACEABLE] bad block scan pattern used for * initial bad block scan * @priv: [OPTIONAL] pointer to private bbm date */ struct bbm_info { int bbt_erase_shift; int badblockpos; int options; uint8_t *bbt; int (*isbad_bbt)(struct mtd_info *mtd, loff_t ofs, int allowbbt); /* TODO Add more NAND specific fileds */ struct nand_bbt_descr *badblock_pattern; void *priv; }; /* OneNAND BBT interface */ extern int onenand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd); extern int onenand_default_bbt(struct mtd_info *mtd); #endif /* __LINUX_MTD_BBM_H */