diff options
Diffstat (limited to 'drivers/mtd/nand/raw/nand_bbt.c')
| -rw-r--r-- | drivers/mtd/nand/raw/nand_bbt.c | 1451 |
1 files changed, 1451 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/nand_bbt.c b/drivers/mtd/nand/raw/nand_bbt.c new file mode 100644 index 000000000..39db352f8 --- /dev/null +++ b/drivers/mtd/nand/raw/nand_bbt.c @@ -0,0 +1,1451 @@ +/* + * Overview: + * Bad block table support for the NAND driver + * + * Copyright © 2004 Thomas Gleixner (tglx@linutronix.de) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Description: + * + * When nand_scan_bbt is called, then it tries to find the bad block table + * depending on the options in the BBT descriptor(s). If no flash based BBT + * (NAND_BBT_USE_FLASH) is specified then the device is scanned for factory + * marked good / bad blocks. This information is used to create a memory BBT. + * Once a new bad block is discovered then the "factory" information is updated + * on the device. + * If a flash based BBT is specified then the function first tries to find the + * BBT on flash. If a BBT is found then the contents are read and the memory + * based BBT is created. If a mirrored BBT is selected then the mirror is + * searched too and the versions are compared. If the mirror has a greater + * version number, then the mirror BBT is used to build the memory based BBT. + * If the tables are not versioned, then we "or" the bad block information. + * If one of the BBTs is out of date or does not exist it is (re)created. + * If no BBT exists at all then the device is scanned for factory marked + * good / bad blocks and the bad block tables are created. + * + * For manufacturer created BBTs like the one found on M-SYS DOC devices + * the BBT is searched and read but never created + * + * The auto generated bad block table is located in the last good blocks + * of the device. The table is mirrored, so it can be updated eventually. + * The table is marked in the OOB area with an ident pattern and a version + * number which indicates which of both tables is more up to date. If the NAND + * controller needs the complete OOB area for the ECC information then the + * option NAND_BBT_NO_OOB should be used (along with NAND_BBT_USE_FLASH, of + * course): it moves the ident pattern and the version byte into the data area + * and the OOB area will remain untouched. + * + * The table uses 2 bits per block + * 11b: block is good + * 00b: block is factory marked bad + * 01b, 10b: block is marked bad due to wear + * + * The memory bad block table uses the following scheme: + * 00b: block is good + * 01b: block is marked bad due to wear + * 10b: block is reserved (to protect the bbt area) + * 11b: block is factory marked bad + * + * Multichip devices like DOC store the bad block info per floor. + * + * Following assumptions are made: + * - bbts start at a page boundary, if autolocated on a block boundary + * - the space necessary for a bbt in FLASH does not exceed a block boundary + * + */ + +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/bbm.h> +#include <linux/mtd/rawnand.h> +#include <linux/bitops.h> +#include <linux/delay.h> +#include <linux/vmalloc.h> +#include <linux/export.h> +#include <linux/string.h> + +#define BBT_BLOCK_GOOD 0x00 +#define BBT_BLOCK_WORN 0x01 +#define BBT_BLOCK_RESERVED 0x02 +#define BBT_BLOCK_FACTORY_BAD 0x03 + +#define BBT_ENTRY_MASK 0x03 +#define BBT_ENTRY_SHIFT 2 + +static int nand_update_bbt(struct mtd_info *mtd, loff_t offs); + +static inline uint8_t bbt_get_entry(struct nand_chip *chip, int block) +{ + uint8_t entry = chip->bbt[block >> BBT_ENTRY_SHIFT]; + entry >>= (block & BBT_ENTRY_MASK) * 2; + return entry & BBT_ENTRY_MASK; +} + +static inline void bbt_mark_entry(struct nand_chip *chip, int block, + uint8_t mark) +{ + uint8_t msk = (mark & BBT_ENTRY_MASK) << ((block & BBT_ENTRY_MASK) * 2); + chip->bbt[block >> BBT_ENTRY_SHIFT] |= msk; +} + +static int check_pattern_no_oob(uint8_t *buf, struct nand_bbt_descr *td) +{ + if (memcmp(buf, td->pattern, td->len)) + return -1; + return 0; +} + +/** + * check_pattern - [GENERIC] check if a pattern is in the buffer + * @buf: the buffer to search + * @len: the length of buffer to search + * @paglen: the pagelength + * @td: search pattern descriptor + * + * Check for a pattern at the given place. Used to search bad block tables and + * good / bad block identifiers. + */ +static int check_pattern(uint8_t *buf, int len, int paglen, struct nand_bbt_descr *td) +{ + if (td->options & NAND_BBT_NO_OOB) + return check_pattern_no_oob(buf, td); + + /* Compare the pattern */ + if (memcmp(buf + paglen + td->offs, td->pattern, td->len)) + return -1; + + return 0; +} + +/** + * check_short_pattern - [GENERIC] check if a pattern is in the buffer + * @buf: the buffer to search + * @td: search pattern descriptor + * + * Check for a pattern at the given place. Used to search bad block tables and + * good / bad block identifiers. Same as check_pattern, but no optional empty + * check. + */ +static int check_short_pattern(uint8_t *buf, struct nand_bbt_descr *td) +{ + /* Compare the pattern */ + if (memcmp(buf + td->offs, td->pattern, td->len)) + return -1; + return 0; +} + +/** + * add_marker_len - compute the length of the marker in data area + * @td: BBT descriptor used for computation + * + * The length will be 0 if the marker is located in OOB area. + */ +static u32 add_marker_len(struct nand_bbt_descr *td) +{ + u32 len; + + if (!(td->options & NAND_BBT_NO_OOB)) + return 0; + + len = td->len; + if (td->options & NAND_BBT_VERSION) + len++; + return len; +} + +/** + * read_bbt - [GENERIC] Read the bad block table starting from page + * @mtd: MTD device structure + * @buf: temporary buffer + * @page: the starting page + * @num: the number of bbt descriptors to read + * @td: the bbt describtion table + * @offs: block number offset in the table + * + * Read the bad block table starting from page. + */ +static int read_bbt(struct mtd_info *mtd, uint8_t *buf, int page, int num, + struct nand_bbt_descr *td, int offs) +{ + int res, ret = 0, i, j, act = 0; + struct nand_chip *this = mtd_to_nand(mtd); + size_t retlen, len, totlen; + loff_t from; + int bits = td->options & NAND_BBT_NRBITS_MSK; + uint8_t msk = (uint8_t)((1 << bits) - 1); + u32 marker_len; + int reserved_block_code = td->reserved_block_code; + + totlen = (num * bits) >> 3; + marker_len = add_marker_len(td); + from = ((loff_t)page) << this->page_shift; + + while (totlen) { + len = min(totlen, (size_t)(1 << this->bbt_erase_shift)); + if (marker_len) { + /* + * In case the BBT marker is not in the OOB area it + * will be just in the first page. + */ + len -= marker_len; + from += marker_len; + marker_len = 0; + } + res = mtd_read(mtd, from, len, &retlen, buf); + if (res < 0) { + if (mtd_is_eccerr(res)) { + pr_info("nand_bbt: ECC error in BBT at 0x%012llx\n", + from & ~mtd->writesize); + return res; + } else if (mtd_is_bitflip(res)) { + pr_info("nand_bbt: corrected error in BBT at 0x%012llx\n", + from & ~mtd->writesize); + ret = res; + } else { + pr_info("nand_bbt: error reading BBT\n"); + return res; + } + } + + /* Analyse data */ + for (i = 0; i < len; i++) { + uint8_t dat = buf[i]; + for (j = 0; j < 8; j += bits, act++) { + uint8_t tmp = (dat >> j) & msk; + if (tmp == msk) + continue; + if (reserved_block_code && (tmp == reserved_block_code)) { + pr_info("nand_read_bbt: reserved block at 0x%012llx\n", + (loff_t)(offs + act) << + this->bbt_erase_shift); + bbt_mark_entry(this, offs + act, + BBT_BLOCK_RESERVED); + mtd->ecc_stats.bbtblocks++; + continue; + } + /* + * Leave it for now, if it's matured we can + * move this message to pr_debug. + */ + pr_info("nand_read_bbt: bad block at 0x%012llx\n", + (loff_t)(offs + act) << + this->bbt_erase_shift); + /* Factory marked bad or worn out? */ + if (tmp == 0) + bbt_mark_entry(this, offs + act, + BBT_BLOCK_FACTORY_BAD); + else + bbt_mark_entry(this, offs + act, + BBT_BLOCK_WORN); + mtd->ecc_stats.badblocks++; + } + } + totlen -= len; + from += len; + } + return ret; +} + +/** + * read_abs_bbt - [GENERIC] Read the bad block table starting at a given page + * @mtd: MTD device structure + * @buf: temporary buffer + * @td: descriptor for the bad block table + * @chip: read the table for a specific chip, -1 read all chips; applies only if + * NAND_BBT_PERCHIP option is set + * + * Read the bad block table for all chips starting at a given page. We assume + * that the bbt bits are in consecutive order. + */ +static int read_abs_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *td, int chip) +{ + struct nand_chip *this = mtd_to_nand(mtd); + int res = 0, i; + + if (td->options & NAND_BBT_PERCHIP) { + int offs = 0; + for (i = 0; i < this->numchips; i++) { + if (chip == -1 || chip == i) + res = read_bbt(mtd, buf, td->pages[i], + this->chipsize >> this->bbt_erase_shift, + td, offs); + if (res) + return res; + offs += this->chipsize >> this->bbt_erase_shift; + } + } else { + res = read_bbt(mtd, buf, td->pages[0], + mtd->size >> this->bbt_erase_shift, td, 0); + if (res) + return res; + } + return 0; +} + +/* BBT marker is in the first page, no OOB */ +static int scan_read_data(struct mtd_info *mtd, uint8_t *buf, loff_t offs, + struct nand_bbt_descr *td) +{ + size_t retlen; + size_t len; + + len = td->len; + if (td->options & NAND_BBT_VERSION) + len++; + + return mtd_read(mtd, offs, len, &retlen, buf); +} + +/** + * scan_read_oob - [GENERIC] Scan data+OOB region to buffer + * @mtd: MTD device structure + * @buf: temporary buffer + * @offs: offset at which to scan + * @len: length of data region to read + * + * Scan read data from data+OOB. May traverse multiple pages, interleaving + * page,OOB,page,OOB,... in buf. Completes transfer and returns the "strongest" + * ECC condition (error or bitflip). May quit on the first (non-ECC) error. + */ +static int scan_read_oob(struct mtd_info *mtd, uint8_t *buf, loff_t offs, + size_t len) +{ + struct mtd_oob_ops ops; + int res, ret = 0; + + ops.mode = MTD_OPS_PLACE_OOB; + ops.ooboffs = 0; + ops.ooblen = mtd->oobsize; + + while (len > 0) { + ops.datbuf = buf; + ops.len = min(len, (size_t)mtd->writesize); + ops.oobbuf = buf + ops.len; + + res = mtd_read_oob(mtd, offs, &ops); + if (res) { + if (!mtd_is_bitflip_or_eccerr(res)) + return res; + else if (mtd_is_eccerr(res) || !ret) + ret = res; + } + + buf += mtd->oobsize + mtd->writesize; + len -= mtd->writesize; + offs += mtd->writesize; + } + return ret; +} + +static int scan_read(struct mtd_info *mtd, uint8_t *buf, loff_t offs, + size_t len, struct nand_bbt_descr *td) +{ + if (td->options & NAND_BBT_NO_OOB) + return scan_read_data(mtd, buf, offs, td); + else + return scan_read_oob(mtd, buf, offs, len); +} + +/* Scan write data with oob to flash */ +static int scan_write_bbt(struct mtd_info *mtd, loff_t offs, size_t len, + uint8_t *buf, uint8_t *oob) +{ + struct mtd_oob_ops ops; + + ops.mode = MTD_OPS_PLACE_OOB; + ops.ooboffs = 0; + ops.ooblen = mtd->oobsize; + ops.datbuf = buf; + ops.oobbuf = oob; + ops.len = len; + + return mtd_write_oob(mtd, offs, &ops); +} + +static u32 bbt_get_ver_offs(struct mtd_info *mtd, struct nand_bbt_descr *td) +{ + u32 ver_offs = td->veroffs; + + if (!(td->options & NAND_BBT_NO_OOB)) + ver_offs += mtd->writesize; + return ver_offs; +} + +/** + * read_abs_bbts - [GENERIC] Read the bad block table(s) for all chips starting at a given page + * @mtd: MTD device structure + * @buf: temporary buffer + * @td: descriptor for the bad block table + * @md: descriptor for the bad block table mirror + * + * Read the bad block table(s) for all chips starting at a given page. We + * assume that the bbt bits are in consecutive order. + */ +static void read_abs_bbts(struct mtd_info *mtd, uint8_t *buf, + struct nand_bbt_descr *td, struct nand_bbt_descr *md) +{ + struct nand_chip *this = mtd_to_nand(mtd); + + /* Read the primary version, if available */ + if (td->options & NAND_BBT_VERSION) { + scan_read(mtd, buf, (loff_t)td->pages[0] << this->page_shift, + mtd->writesize, td); + td->version[0] = buf[bbt_get_ver_offs(mtd, td)]; + pr_info("Bad block table at page %d, version 0x%02X\n", + td->pages[0], td->version[0]); + } + + /* Read the mirror version, if available */ + if (md && (md->options & NAND_BBT_VERSION)) { + scan_read(mtd, buf, (loff_t)md->pages[0] << this->page_shift, + mtd->writesize, md); + md->version[0] = buf[bbt_get_ver_offs(mtd, md)]; + pr_info("Bad block table at page %d, version 0x%02X\n", + md->pages[0], md->version[0]); + } +} + +/* Scan a given block partially */ +static int scan_block_fast(struct mtd_info *mtd, struct nand_bbt_descr *bd, + loff_t offs, uint8_t *buf, int numpages) +{ + struct mtd_oob_ops ops; + int j, ret; + + ops.ooblen = mtd->oobsize; + ops.oobbuf = buf; + ops.ooboffs = 0; + ops.datbuf = NULL; + ops.mode = MTD_OPS_PLACE_OOB; + + for (j = 0; j < numpages; j++) { + /* + * Read the full oob until read_oob is fixed to handle single + * byte reads for 16 bit buswidth. + */ + ret = mtd_read_oob(mtd, offs, &ops); + /* Ignore ECC errors when checking for BBM */ + if (ret && !mtd_is_bitflip_or_eccerr(ret)) + return ret; + + if (check_short_pattern(buf, bd)) + return 1; + + offs += mtd->writesize; + } + return 0; +} + +/** + * create_bbt - [GENERIC] Create a bad block table by scanning the device + * @mtd: MTD device structure + * @buf: temporary buffer + * @bd: descriptor for the good/bad block search pattern + * @chip: create the table for a specific chip, -1 read all chips; applies only + * if NAND_BBT_PERCHIP option is set + * + * Create a bad block table by scanning the device for the given good/bad block + * identify pattern. + */ +static int create_bbt(struct mtd_info *mtd, uint8_t *buf, + struct nand_bbt_descr *bd, int chip) +{ + struct nand_chip *this = mtd_to_nand(mtd); + int i, numblocks, numpages; + int startblock; + loff_t from; + + pr_info("Scanning device for bad blocks\n"); + + if (bd->options & NAND_BBT_SCAN2NDPAGE) + numpages = 2; + else + numpages = 1; + + if (chip == -1) { + numblocks = mtd->size >> this->bbt_erase_shift; + startblock = 0; + from = 0; + } else { + if (chip >= this->numchips) { + pr_warn("create_bbt(): chipnr (%d) > available chips (%d)\n", + chip + 1, this->numchips); + return -EINVAL; + } + numblocks = this->chipsize >> this->bbt_erase_shift; + startblock = chip * numblocks; + numblocks += startblock; + from = (loff_t)startblock << this->bbt_erase_shift; + } + + if (this->bbt_options & NAND_BBT_SCANLASTPAGE) + from += mtd->erasesize - (mtd->writesize * numpages); + + for (i = startblock; i < numblocks; i++) { + int ret; + + BUG_ON(bd->options & NAND_BBT_NO_OOB); + + ret = scan_block_fast(mtd, bd, from, buf, numpages); + if (ret < 0) + return ret; + + if (ret) { + bbt_mark_entry(this, i, BBT_BLOCK_FACTORY_BAD); + pr_warn("Bad eraseblock %d at 0x%012llx\n", + i, (unsigned long long)from); + mtd->ecc_stats.badblocks++; + } + + from += (1 << this->bbt_erase_shift); + } + return 0; +} + +/** + * search_bbt - [GENERIC] scan the device for a specific bad block table + * @mtd: MTD device structure + * @buf: temporary buffer + * @td: descriptor for the bad block table + * + * Read the bad block table by searching for a given ident pattern. Search is + * preformed either from the beginning up or from the end of the device + * downwards. The search starts always at the start of a block. If the option + * NAND_BBT_PERCHIP is given, each chip is searched for a bbt, which contains + * the bad block information of this chip. This is necessary to provide support + * for certain DOC devices. + * + * The bbt ident pattern resides in the oob area of the first page in a block. + */ +static int search_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *td) +{ + struct nand_chip *this = mtd_to_nand(mtd); + int i, chips; + int startblock, block, dir; + int scanlen = mtd->writesize + mtd->oobsize; + int bbtblocks; + int blocktopage = this->bbt_erase_shift - this->page_shift; + + /* Search direction top -> down? */ + if (td->options & NAND_BBT_LASTBLOCK) { + startblock = (mtd->size >> this->bbt_erase_shift) - 1; + dir = -1; + } else { + startblock = 0; + dir = 1; + } + + /* Do we have a bbt per chip? */ + if (td->options & NAND_BBT_PERCHIP) { + chips = this->numchips; + bbtblocks = this->chipsize >> this->bbt_erase_shift; + startblock &= bbtblocks - 1; + } else { + chips = 1; + bbtblocks = mtd->size >> this->bbt_erase_shift; + } + + for (i = 0; i < chips; i++) { + /* Reset version information */ + td->version[i] = 0; + td->pages[i] = -1; + /* Scan the maximum number of blocks */ + for (block = 0; block < td->maxblocks; block++) { + + int actblock = startblock + dir * block; + loff_t offs = (loff_t)actblock << this->bbt_erase_shift; + + /* Read first page */ + scan_read(mtd, buf, offs, mtd->writesize, td); + if (!check_pattern(buf, scanlen, mtd->writesize, td)) { + td->pages[i] = actblock << blocktopage; + if (td->options & NAND_BBT_VERSION) { + offs = bbt_get_ver_offs(mtd, td); + td->version[i] = buf[offs]; + } + break; + } + } + startblock += this->chipsize >> this->bbt_erase_shift; + } + /* Check, if we found a bbt for each requested chip */ + for (i = 0; i < chips; i++) { + if (td->pages[i] == -1) + pr_warn("Bad block table not found for chip %d\n", i); + else + pr_info("Bad block table found at page %d, version 0x%02X\n", + td->pages[i], td->version[i]); + } + return 0; +} + +/** + * search_read_bbts - [GENERIC] scan the device for bad block table(s) + * @mtd: MTD device structure + * @buf: temporary buffer + * @td: descriptor for the bad block table + * @md: descriptor for the bad block table mirror + * + * Search and read the bad block table(s). + */ +static void search_read_bbts(struct mtd_info *mtd, uint8_t *buf, + struct nand_bbt_descr *td, + struct nand_bbt_descr *md) +{ + /* Search the primary table */ + search_bbt(mtd, buf, td); + + /* Search the mirror table */ + if (md) + search_bbt(mtd, buf, md); +} + +/** + * get_bbt_block - Get the first valid eraseblock suitable to store a BBT + * @this: the NAND device + * @td: the BBT description + * @md: the mirror BBT descriptor + * @chip: the CHIP selector + * + * This functions returns a positive block number pointing a valid eraseblock + * suitable to store a BBT (i.e. in the range reserved for BBT), or -ENOSPC if + * all blocks are already used of marked bad. If td->pages[chip] was already + * pointing to a valid block we re-use it, otherwise we search for the next + * valid one. + */ +static int get_bbt_block(struct nand_chip *this, struct nand_bbt_descr *td, + struct nand_bbt_descr *md, int chip) +{ + int startblock, dir, page, numblocks, i; + + /* + * There was already a version of the table, reuse the page. This + * applies for absolute placement too, as we have the page number in + * td->pages. + */ + if (td->pages[chip] != -1) + return td->pages[chip] >> + (this->bbt_erase_shift - this->page_shift); + + numblocks = (int)(this->chipsize >> this->bbt_erase_shift); + if (!(td->options & NAND_BBT_PERCHIP)) + numblocks *= this->numchips; + + /* + * Automatic placement of the bad block table. Search direction + * top -> down? + */ + if (td->options & NAND_BBT_LASTBLOCK) { + startblock = numblocks * (chip + 1) - 1; + dir = -1; + } else { + startblock = chip * numblocks; + dir = 1; + } + + for (i = 0; i < td->maxblocks; i++) { + int block = startblock + dir * i; + + /* Check, if the block is bad */ + switch (bbt_get_entry(this, block)) { + case BBT_BLOCK_WORN: + case BBT_BLOCK_FACTORY_BAD: + continue; + } + + page = block << (this->bbt_erase_shift - this->page_shift); + + /* Check, if the block is used by the mirror table */ + if (!md || md->pages[chip] != page) + return block; + } + + return -ENOSPC; +} + +/** + * mark_bbt_block_bad - Mark one of the block reserved for BBT bad + * @this: the NAND device + * @td: the BBT description + * @chip: the CHIP selector + * @block: the BBT block to mark + * + * Blocks reserved for BBT can become bad. This functions is an helper to mark + * such blocks as bad. It takes care of updating the in-memory BBT, marking the + * block as bad using a bad block marker and invalidating the associated + * td->pages[] entry. + */ +static void mark_bbt_block_bad(struct nand_chip *this, + struct nand_bbt_descr *td, + int chip, int block) +{ + struct mtd_info *mtd = nand_to_mtd(this); + loff_t to; + int res; + + bbt_mark_entry(this, block, BBT_BLOCK_WORN); + + to = (loff_t)block << this->bbt_erase_shift; + res = this->block_markbad(mtd, to); + if (res) + pr_warn("nand_bbt: error %d while marking block %d bad\n", + res, block); + + td->pages[chip] = -1; +} + +/** + * write_bbt - [GENERIC] (Re)write the bad block table + * @mtd: MTD device structure + * @buf: temporary buffer + * @td: descriptor for the bad block table + * @md: descriptor for the bad block table mirror + * @chipsel: selector for a specific chip, -1 for all + * + * (Re)write the bad block table. + */ +static int write_bbt(struct mtd_info *mtd, uint8_t *buf, + struct nand_bbt_descr *td, struct nand_bbt_descr *md, + int chipsel) +{ + struct nand_chip *this = mtd_to_nand(mtd); + struct erase_info einfo; + int i, res, chip = 0; + int bits, page, offs, numblocks, sft, sftmsk; + int nrchips, pageoffs, ooboffs; + uint8_t msk[4]; + uint8_t rcode = td->reserved_block_code; + size_t retlen, len = 0; + loff_t to; + struct mtd_oob_ops ops; + + ops.ooblen = mtd->oobsize; + ops.ooboffs = 0; + ops.datbuf = NULL; + ops.mode = MTD_OPS_PLACE_OOB; + + if (!rcode) + rcode = 0xff; + /* Write bad block table per chip rather than per device? */ + if (td->options & NAND_BBT_PERCHIP) { + numblocks = (int)(this->chipsize >> this->bbt_erase_shift); + /* Full device write or specific chip? */ + if (chipsel == -1) { + nrchips = this->numchips; + } else { + nrchips = chipsel + 1; + chip = chipsel; + } + } else { + numblocks = (int)(mtd->size >> this->bbt_erase_shift); + nrchips = 1; + } + + /* Loop through the chips */ + while (chip < nrchips) { + int block; + + block = get_bbt_block(this, td, md, chip); + if (block < 0) { + pr_err("No space left to write bad block table\n"); + res = block; + goto outerr; + } + + /* + * get_bbt_block() returns a block number, shift the value to + * get a page number. + */ + page = block << (this->bbt_erase_shift - this->page_shift); + + /* Set up shift count and masks for the flash table */ + bits = td->options & NAND_BBT_NRBITS_MSK; + msk[2] = ~rcode; + switch (bits) { + case 1: sft = 3; sftmsk = 0x07; msk[0] = 0x00; msk[1] = 0x01; + msk[3] = 0x01; + break; + case 2: sft = 2; sftmsk = 0x06; msk[0] = 0x00; msk[1] = 0x01; + msk[3] = 0x03; + break; + case 4: sft = 1; sftmsk = 0x04; msk[0] = 0x00; msk[1] = 0x0C; + msk[3] = 0x0f; + break; + case 8: sft = 0; sftmsk = 0x00; msk[0] = 0x00; msk[1] = 0x0F; + msk[3] = 0xff; + break; + default: return -EINVAL; + } + + to = ((loff_t)page) << this->page_shift; + + /* Must we save the block contents? */ + if (td->options & NAND_BBT_SAVECONTENT) { + /* Make it block aligned */ + to &= ~(((loff_t)1 << this->bbt_erase_shift) - 1); + len = 1 << this->bbt_erase_shift; + res = mtd_read(mtd, to, len, &retlen, buf); + if (res < 0) { + if (retlen != len) { + pr_info("nand_bbt: error reading block for writing the bad block table\n"); + return res; + } + pr_warn("nand_bbt: ECC error while reading block for writing bad block table\n"); + } + /* Read oob data */ + ops.ooblen = (len >> this->page_shift) * mtd->oobsize; + ops.oobbuf = &buf[len]; + res = mtd_read_oob(mtd, to + mtd->writesize, &ops); + if (res < 0 || ops.oobretlen != ops.ooblen) + goto outerr; + + /* Calc the byte offset in the buffer */ + pageoffs = page - (int)(to >> this->page_shift); + offs = pageoffs << this->page_shift; + /* Preset the bbt area with 0xff */ + memset(&buf[offs], 0xff, (size_t)(numblocks >> sft)); + ooboffs = len + (pageoffs * mtd->oobsize); + + } else if (td->options & NAND_BBT_NO_OOB) { + ooboffs = 0; + offs = td->len; + /* The version byte */ + if (td->options & NAND_BBT_VERSION) + offs++; + /* Calc length */ + len = (size_t)(numblocks >> sft); + len += offs; + /* Make it page aligned! */ + len = ALIGN(len, mtd->writesize); + /* Preset the buffer with 0xff */ + memset(buf, 0xff, len); + /* Pattern is located at the begin of first page */ + memcpy(buf, td->pattern, td->len); + } else { + /* Calc length */ + len = (size_t)(numblocks >> sft); + /* Make it page aligned! */ + len = ALIGN(len, mtd->writesize); + /* Preset the buffer with 0xff */ + memset(buf, 0xff, len + + (len >> this->page_shift)* mtd->oobsize); + offs = 0; + ooboffs = len; + /* Pattern is located in oob area of first page */ + memcpy(&buf[ooboffs + td->offs], td->pattern, td->len); + } + + if (td->options & NAND_BBT_VERSION) + buf[ooboffs + td->veroffs] = td->version[chip]; + + /* Walk through the memory table */ + for (i = 0; i < numblocks; i++) { + uint8_t dat; + int sftcnt = (i << (3 - sft)) & sftmsk; + dat = bbt_get_entry(this, chip * numblocks + i); + /* Do not store the reserved bbt blocks! */ + buf[offs + (i >> sft)] &= ~(msk[dat] << sftcnt); + } + + memset(&einfo, 0, sizeof(einfo)); + einfo.addr = to; + einfo.len = 1 << this->bbt_erase_shift; + res = nand_erase_nand(mtd, &einfo, 1); + if (res < 0) { + pr_warn("nand_bbt: error while erasing BBT block %d\n", + res); + mark_bbt_block_bad(this, td, chip, block); + continue; + } + + res = scan_write_bbt(mtd, to, len, buf, + td->options & NAND_BBT_NO_OOB ? NULL : + &buf[len]); + if (res < 0) { + pr_warn("nand_bbt: error while writing BBT block %d\n", + res); + mark_bbt_block_bad(this, td, chip, block); + continue; + } + + pr_info("Bad block table written to 0x%012llx, version 0x%02X\n", + (unsigned long long)to, td->version[chip]); + + /* Mark it as used */ + td->pages[chip++] = page; + } + return 0; + + outerr: + pr_warn("nand_bbt: error while writing bad block table %d\n", res); + return res; +} + +/** + * nand_memory_bbt - [GENERIC] create a memory based bad block table + * @mtd: MTD device structure + * @bd: descriptor for the good/bad block search pattern + * + * The function creates a memory based bbt by scanning the device for + * manufacturer / software marked good / bad blocks. + */ +static inline int nand_memory_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd) +{ + struct nand_chip *this = mtd_to_nand(mtd); + + return create_bbt(mtd, this->data_buf, bd, -1); +} + +/** + * check_create - [GENERIC] create and write bbt(s) if necessary + * @mtd: MTD device structure + * @buf: temporary buffer + * @bd: descriptor for the good/bad block search pattern + * + * The function checks the results of the previous call to read_bbt and creates + * / updates the bbt(s) if necessary. Creation is necessary if no bbt was found + * for the chip/device. Update is necessary if one of the tables is missing or + * the version nr. of one table is less than the other. + */ +static int check_create(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *bd) +{ + int i, chips, writeops, create, chipsel, res, res2; + struct nand_chip *this = mtd_to_nand(mtd); + struct nand_bbt_descr *td = this->bbt_td; + struct nand_bbt_descr *md = this->bbt_md; + struct nand_bbt_descr *rd, *rd2; + + /* Do we have a bbt per chip? */ + if (td->options & NAND_BBT_PERCHIP) + chips = this->numchips; + else + chips = 1; + + for (i = 0; i < chips; i++) { + writeops = 0; + create = 0; + rd = NULL; + rd2 = NULL; + res = res2 = 0; + /* Per chip or per device? */ + chipsel = (td->options & NAND_BBT_PERCHIP) ? i : -1; + /* Mirrored table available? */ + if (md) { + if (td->pages[i] == -1 && md->pages[i] == -1) { + create = 1; + writeops = 0x03; + } else if (td->pages[i] == -1) { + rd = md; + writeops = 0x01; + } else if (md->pages[i] == -1) { + rd = td; + writeops = 0x02; + } else if (td->version[i] == md->version[i]) { + rd = td; + if (!(td->options & NAND_BBT_VERSION)) + rd2 = md; + } else if (((int8_t)(td->version[i] - md->version[i])) > 0) { + rd = td; + writeops = 0x02; + } else { + rd = md; + writeops = 0x01; + } + } else { + if (td->pages[i] == -1) { + create = 1; + writeops = 0x01; + } else { + rd = td; + } + } + + if (create) { + /* Create the bad block table by scanning the device? */ + if (!(td->options & NAND_BBT_CREATE)) + continue; + + /* Create the table in memory by scanning the chip(s) */ + if (!(this->bbt_options & NAND_BBT_CREATE_EMPTY)) + create_bbt(mtd, buf, bd, chipsel); + + td->version[i] = 1; + if (md) + md->version[i] = 1; + } + + /* Read back first? */ + if (rd) { + res = read_abs_bbt(mtd, buf, rd, chipsel); + if (mtd_is_eccerr(res)) { + /* Mark table as invalid */ + rd->pages[i] = -1; + rd->version[i] = 0; + i--; + continue; + } + } + /* If they weren't versioned, read both */ + if (rd2) { + res2 = read_abs_bbt(mtd, buf, rd2, chipsel); + if (mtd_is_eccerr(res2)) { + /* Mark table as invalid */ + rd2->pages[i] = -1; + rd2->version[i] = 0; + i--; + continue; + } + } + + /* Scrub the flash table(s)? */ + if (mtd_is_bitflip(res) || mtd_is_bitflip(res2)) + writeops = 0x03; + + /* Update version numbers before writing */ + if (md) { + td->version[i] = max(td->version[i], md->version[i]); + md->version[i] = td->version[i]; + } + + /* Write the bad block table to the device? */ + if ((writeops & 0x01) && (td->options & NAND_BBT_WRITE)) { + res = write_bbt(mtd, buf, td, md, chipsel); + if (res < 0) + return res; + } + + /* Write the mirror bad block table to the device? */ + if ((writeops & 0x02) && md && (md->options & NAND_BBT_WRITE)) { + res = write_bbt(mtd, buf, md, td, chipsel); + if (res < 0) + return res; + } + } + return 0; +} + +/** + * mark_bbt_regions - [GENERIC] mark the bad block table regions + * @mtd: MTD device structure + * @td: bad block table descriptor + * + * The bad block table regions are marked as "bad" to prevent accidental + * erasures / writes. The regions are identified by the mark 0x02. + */ +static void mark_bbt_region(struct mtd_info *mtd, struct nand_bbt_descr *td) +{ + struct nand_chip *this = mtd_to_nand(mtd); + int i, j, chips, block, nrblocks, update; + uint8_t oldval; + + /* Do we have a bbt per chip? */ + if (td->options & NAND_BBT_PERCHIP) { + chips = this->numchips; + nrblocks = (int)(this->chipsize >> this->bbt_erase_shift); + } else { + chips = 1; + nrblocks = (int)(mtd->size >> this->bbt_erase_shift); + } + + for (i = 0; i < chips; i++) { + if ((td->options & NAND_BBT_ABSPAGE) || + !(td->options & NAND_BBT_WRITE)) { + if (td->pages[i] == -1) + continue; + block = td->pages[i] >> (this->bbt_erase_shift - this->page_shift); + oldval = bbt_get_entry(this, block); + bbt_mark_entry(this, block, BBT_BLOCK_RESERVED); + if ((oldval != BBT_BLOCK_RESERVED) && + td->reserved_block_code) + nand_update_bbt(mtd, (loff_t)block << + this->bbt_erase_shift); + continue; + } + update = 0; + if (td->options & NAND_BBT_LASTBLOCK) + block = ((i + 1) * nrblocks) - td->maxblocks; + else + block = i * nrblocks; + for (j = 0; j < td->maxblocks; j++) { + oldval = bbt_get_entry(this, block); + bbt_mark_entry(this, block, BBT_BLOCK_RESERVED); + if (oldval != BBT_BLOCK_RESERVED) + update = 1; + block++; + } + /* + * If we want reserved blocks to be recorded to flash, and some + * new ones have been marked, then we need to update the stored + * bbts. This should only happen once. + */ + if (update && td->reserved_block_code) + nand_update_bbt(mtd, (loff_t)(block - 1) << + this->bbt_erase_shift); + } +} + +/** + * verify_bbt_descr - verify the bad block description + * @mtd: MTD device structure + * @bd: the table to verify + * + * This functions performs a few sanity checks on the bad block description + * table. + */ +static void verify_bbt_descr(struct mtd_info *mtd, struct nand_bbt_descr *bd) +{ + struct nand_chip *this = mtd_to_nand(mtd); + u32 pattern_len; + u32 bits; + u32 table_size; + + if (!bd) + return; + + pattern_len = bd->len; + bits = bd->options & NAND_BBT_NRBITS_MSK; + + BUG_ON((this->bbt_options & NAND_BBT_NO_OOB) && + !(this->bbt_options & NAND_BBT_USE_FLASH)); + BUG_ON(!bits); + + if (bd->options & NAND_BBT_VERSION) + pattern_len++; + + if (bd->options & NAND_BBT_NO_OOB) { + BUG_ON(!(this->bbt_options & NAND_BBT_USE_FLASH)); + BUG_ON(!(this->bbt_options & NAND_BBT_NO_OOB)); + BUG_ON(bd->offs); + if (bd->options & NAND_BBT_VERSION) + BUG_ON(bd->veroffs != bd->len); + BUG_ON(bd->options & NAND_BBT_SAVECONTENT); + } + + if (bd->options & NAND_BBT_PERCHIP) + table_size = this->chipsize >> this->bbt_erase_shift; + else + table_size = mtd->size >> this->bbt_erase_shift; + table_size >>= 3; + table_size *= bits; + if (bd->options & NAND_BBT_NO_OOB) + table_size += pattern_len; + BUG_ON(table_size > (1 << this->bbt_erase_shift)); +} + +/** + * nand_scan_bbt - [NAND Interface] scan, find, read and maybe create bad block table(s) + * @mtd: MTD device structure + * @bd: descriptor for the good/bad block search pattern + * + * The function checks, if a bad block table(s) is/are already available. If + * not it scans the device for manufacturer marked good / bad blocks and writes + * the bad block table(s) to the selected place. + * + * The bad block table memory is allocated here. It must be freed by calling + * the nand_free_bbt function. + */ +static int nand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd) +{ + struct nand_chip *this = mtd_to_nand(mtd); + int len, res; + uint8_t *buf; + struct nand_bbt_descr *td = this->bbt_td; + struct nand_bbt_descr *md = this->bbt_md; + + len = (mtd->size >> (this->bbt_erase_shift + 2)) ? : 1; + /* + * Allocate memory (2bit per block) and clear the memory bad block + * table. + */ + this->bbt = kzalloc(len, GFP_KERNEL); + if (!this->bbt) + return -ENOMEM; + + /* + * If no primary table decriptor is given, scan the device to build a + * memory based bad block table. + */ + if (!td) { + if ((res = nand_memory_bbt(mtd, bd))) { + pr_err("nand_bbt: can't scan flash and build the RAM-based BBT\n"); + goto err; + } + return 0; + } + verify_bbt_descr(mtd, td); + verify_bbt_descr(mtd, md); + + /* Allocate a temporary buffer for one eraseblock incl. oob */ + len = (1 << this->bbt_erase_shift); + len += (len >> this->page_shift) * mtd->oobsize; + buf = vmalloc(len); + if (!buf) { + res = -ENOMEM; + goto err; + } + + /* Is the bbt at a given page? */ + if (td->options & NAND_BBT_ABSPAGE) { + read_abs_bbts(mtd, buf, td, md); + } else { + /* Search the bad block table using a pattern in oob */ + search_read_bbts(mtd, buf, td, md); + } + + res = check_create(mtd, buf, bd); + if (res) + goto err; + + /* Prevent the bbt regions from erasing / writing */ + mark_bbt_region(mtd, td); + if (md) + mark_bbt_region(mtd, md); + + vfree(buf); + return 0; + +err: + kfree(this->bbt); + this->bbt = NULL; + return res; +} + +/** + * nand_update_bbt - update bad block table(s) + * @mtd: MTD device structure + * @offs: the offset of the newly marked block + * + * The function updates the bad block table(s). + */ +static int nand_update_bbt(struct mtd_info *mtd, loff_t offs) +{ + struct nand_chip *this = mtd_to_nand(mtd); + int len, res = 0; + int chip, chipsel; + uint8_t *buf; + struct nand_bbt_descr *td = this->bbt_td; + struct nand_bbt_descr *md = this->bbt_md; + + if (!this->bbt || !td) + return -EINVAL; + + /* Allocate a temporary buffer for one eraseblock incl. oob */ + len = (1 << this->bbt_erase_shift); + len += (len >> this->page_shift) * mtd->oobsize; + buf = kmalloc(len, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + /* Do we have a bbt per chip? */ + if (td->options & NAND_BBT_PERCHIP) { + chip = (int)(offs >> this->chip_shift); + chipsel = chip; + } else { + chip = 0; + chipsel = -1; + } + + td->version[chip]++; + if (md) + md->version[chip]++; + + /* Write the bad block table to the device? */ + if (td->options & NAND_BBT_WRITE) { + res = write_bbt(mtd, buf, td, md, chipsel); + if (res < 0) + goto out; + } + /* Write the mirror bad block table to the device? */ + if (md && (md->options & NAND_BBT_WRITE)) { + res = write_bbt(mtd, buf, md, td, chipsel); + } + + out: + kfree(buf); + return res; +} + +/* + * Define some generic bad / good block scan pattern which are used + * while scanning a device for factory marked good / bad blocks. + */ +static uint8_t scan_ff_pattern[] = { 0xff, 0xff }; + +/* Generic flash bbt descriptors */ +static uint8_t bbt_pattern[] = {'B', 'b', 't', '0' }; +static uint8_t mirror_pattern[] = {'1', 't', 'b', 'B' }; + +static struct nand_bbt_descr bbt_main_descr = { + .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE + | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP, + .offs = 8, + .len = 4, + .veroffs = 12, + .maxblocks = NAND_BBT_SCAN_MAXBLOCKS, + .pattern = bbt_pattern +}; + +static struct nand_bbt_descr bbt_mirror_descr = { + .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE + | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP, + .offs = 8, + .len = 4, + .veroffs = 12, + .maxblocks = NAND_BBT_SCAN_MAXBLOCKS, + .pattern = mirror_pattern +}; + +static struct nand_bbt_descr bbt_main_no_oob_descr = { + .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE + | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP + | NAND_BBT_NO_OOB, + .len = 4, + .veroffs = 4, + .maxblocks = NAND_BBT_SCAN_MAXBLOCKS, + .pattern = bbt_pattern +}; + +static struct nand_bbt_descr bbt_mirror_no_oob_descr = { + .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE + | NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP + | NAND_BBT_NO_OOB, + .len = 4, + .veroffs = 4, + .maxblocks = NAND_BBT_SCAN_MAXBLOCKS, + .pattern = mirror_pattern +}; + +#define BADBLOCK_SCAN_MASK (~NAND_BBT_NO_OOB) +/** + * nand_create_badblock_pattern - [INTERN] Creates a BBT descriptor structure + * @this: NAND chip to create descriptor for + * + * This function allocates and initializes a nand_bbt_descr for BBM detection + * based on the properties of @this. The new descriptor is stored in + * this->badblock_pattern. Thus, this->badblock_pattern should be NULL when + * passed to this function. + */ +static int nand_create_badblock_pattern(struct nand_chip *this) +{ + struct nand_bbt_descr *bd; + if (this->badblock_pattern) { + pr_warn("Bad block pattern already allocated; not replacing\n"); + return -EINVAL; + } + bd = kzalloc(sizeof(*bd), GFP_KERNEL); + if (!bd) + return -ENOMEM; + bd->options = this->bbt_options & BADBLOCK_SCAN_MASK; + bd->offs = this->badblockpos; + bd->len = (this->options & NAND_BUSWIDTH_16) ? 2 : 1; + bd->pattern = scan_ff_pattern; + bd->options |= NAND_BBT_DYNAMICSTRUCT; + this->badblock_pattern = bd; + return 0; +} + +/** + * nand_create_bbt - [NAND Interface] Select a default bad block table for the device + * @this: NAND chip object + * + * This function selects the default bad block table support for the device and + * calls the nand_scan_bbt function. + */ +int nand_create_bbt(struct nand_chip *this) +{ + int ret; + + /* Is a flash based bad block table requested? */ + if (this->bbt_options & NAND_BBT_USE_FLASH) { + /* Use the default pattern descriptors */ + if (!this->bbt_td) { + if (this->bbt_options & NAND_BBT_NO_OOB) { + this->bbt_td = &bbt_main_no_oob_descr; + this->bbt_md = &bbt_mirror_no_oob_descr; + } else { + this->bbt_td = &bbt_main_descr; + this->bbt_md = &bbt_mirror_descr; + } + } + } else { + this->bbt_td = NULL; + this->bbt_md = NULL; + } + + if (!this->badblock_pattern) { + ret = nand_create_badblock_pattern(this); + if (ret) + return ret; + } + + return nand_scan_bbt(nand_to_mtd(this), this->badblock_pattern); +} +EXPORT_SYMBOL(nand_create_bbt); + +/** + * nand_isreserved_bbt - [NAND Interface] Check if a block is reserved + * @mtd: MTD device structure + * @offs: offset in the device + */ +int nand_isreserved_bbt(struct mtd_info *mtd, loff_t offs) +{ + struct nand_chip *this = mtd_to_nand(mtd); + int block; + + block = (int)(offs >> this->bbt_erase_shift); + return bbt_get_entry(this, block) == BBT_BLOCK_RESERVED; +} + +/** + * nand_isbad_bbt - [NAND Interface] Check if a block is bad + * @mtd: MTD device structure + * @offs: offset in the device + * @allowbbt: allow access to bad block table region + */ +int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt) +{ + struct nand_chip *this = mtd_to_nand(mtd); + int block, res; + + block = (int)(offs >> this->bbt_erase_shift); + res = bbt_get_entry(this, block); + + pr_debug("nand_isbad_bbt(): bbt info for offs 0x%08x: (block %d) 0x%02x\n", + (unsigned int)offs, block, res); + + switch (res) { + case BBT_BLOCK_GOOD: + return 0; + case BBT_BLOCK_WORN: + return 1; + case BBT_BLOCK_RESERVED: + return allowbbt ? 0 : 1; + } + return 1; +} + +/** + * nand_markbad_bbt - [NAND Interface] Mark a block bad in the BBT + * @mtd: MTD device structure + * @offs: offset of the bad block + */ +int nand_markbad_bbt(struct mtd_info *mtd, loff_t offs) +{ + struct nand_chip *this = mtd_to_nand(mtd); + int block, ret = 0; + + block = (int)(offs >> this->bbt_erase_shift); + + /* Mark bad block in memory */ + bbt_mark_entry(this, block, BBT_BLOCK_WORN); + + /* Update flash-based bad block table */ + if (this->bbt_options & NAND_BBT_USE_FLASH) + ret = nand_update_bbt(mtd, offs); + + return ret; +} |