[PATCH 12/12] mtd: nand-bbt: move nand_bbt.c to mtd folder
Peter Pan 潘栋 (peterpandong)
peterpandong at micron.com
Thu Sep 24 23:48:05 PDT 2015
Since struct nand_chip is removed from nand_bbt.c, BBT is now
shareable. Both NAND and SPI NAND can use it. So move nand_bbt.c
from nand/ foler to mtd/ folder and create MTD_NAND_BBT config.
Both NAND and SPI NAND should depend on MTD_NAND_BBT.
Signed-off-by: Peter Pan <peterpandong at micron.com>
---
drivers/mtd/Kconfig | 7 +
drivers/mtd/Makefile | 1 +
drivers/mtd/nand/Kconfig | 2 +-
drivers/mtd/nand/Makefile | 2 +-
drivers/mtd/nand/nand_bbt.c | 1289 -------------------------------------------
drivers/mtd/nand_bbt.c | 1289 +++++++++++++++++++++++++++++++++++++++++++
6 files changed, 1299 insertions(+), 1291 deletions(-)
delete mode 100644 drivers/mtd/nand/nand_bbt.c
create mode 100644 drivers/mtd/nand_bbt.c
diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig
index a03ad29..eb6a33c 100644
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -322,6 +322,13 @@ config MTD_PARTITIONED_MASTER
the parent of the partition device be the master device, rather than
what lies behind the master.
+config MTD_NAND_BBT
+ tristate "Bad Block Table support for NAND based devices"
+ depends on MTD
+ help
+ Since struct nand_chip is removed from nand_bbt.c, BBT is now
+ shareable. Both NAND and SPI NAND can use it.
+
source "drivers/mtd/chips/Kconfig"
source "drivers/mtd/maps/Kconfig"
diff --git a/drivers/mtd/Makefile b/drivers/mtd/Makefile
index 99bb9a1..55aed6f 100644
--- a/drivers/mtd/Makefile
+++ b/drivers/mtd/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_SSFDC) += ssfdc.o
obj-$(CONFIG_SM_FTL) += sm_ftl.o
obj-$(CONFIG_MTD_OOPS) += mtdoops.o
obj-$(CONFIG_MTD_SWAP) += mtdswap.o
+obj-$(CONFIG_MTD_NAND_BBT) += nand_bbt.o
nftl-objs := nftlcore.o nftlmount.o
inftl-objs := inftlcore.o inftlmount.o
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 3324281..6ca3a6f 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -12,7 +12,7 @@ config MTD_NAND_ECC_SMC
menuconfig MTD_NAND
tristate "NAND Device Support"
- depends on MTD
+ depends on MTD && MTD_NAND_BBT
select MTD_NAND_IDS
select MTD_NAND_ECC
help
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index 075a027..c6887d0 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -55,4 +55,4 @@ obj-$(CONFIG_MTD_NAND_SUNXI) += sunxi_nand.o
obj-$(CONFIG_MTD_NAND_HISI504) += hisi504_nand.o
obj-$(CONFIG_MTD_NAND_BRCMNAND) += brcmnand/
-nand-objs := nand_base.o nand_bbt.o nand_timings.o
+nand-objs := nand_base.o nand_timings.o
diff --git a/drivers/mtd/nand/nand_bbt.c b/drivers/mtd/nand/nand_bbt.c
deleted file mode 100644
index 47c1084..0000000
--- a/drivers/mtd/nand/nand_bbt.c
+++ /dev/null
@@ -1,1289 +0,0 @@
-/*
- * Overview:
- * Bad block table support for the NAND driver
- *
- * Copyright ? 2004 Thomas Gleixner (tglx at 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/nand_bbt.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 nand_bbt *bbt, loff_t offs);
-
-static inline uint8_t bbt_get_entry(struct nand_bbt *bbt, int block)
-{
- uint8_t entry = bbt->bbt[block >> BBT_ENTRY_SHIFT];
- entry >>= (block & BBT_ENTRY_MASK) * 2;
- return entry & BBT_ENTRY_MASK;
-}
-
-static inline void bbt_mark_entry(struct nand_bbt *bbt, int block,
- uint8_t mark)
-{
- uint8_t msk = (mark & BBT_ENTRY_MASK) << ((block & BBT_ENTRY_MASK) * 2);
- bbt->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;
-}
-
-/**
- * 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
- * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf, int page, int num,
- struct nand_bbt_descr *td, int offs)
-{
- struct mtd_info *mtd = bbt->mtd;
- int res, ret = 0, i, j, act = 0;
- 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) << bbt->page_shift;
-
- while (totlen) {
- len = min(totlen, (size_t)(1 << bbt->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) <<
- bbt->bbt_erase_shift);
- bbt_mark_entry(bbt, 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) <<
- bbt->bbt_erase_shift);
- /* Factory marked bad or worn out? */
- if (tmp == 0)
- bbt_mark_entry(bbt, offs + act,
- BBT_BLOCK_FACTORY_BAD);
- else
- bbt_mark_entry(bbt, 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
- * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf, struct nand_bbt_descr *td, int chip)
-{
- struct mtd_info *mtd = bbt->mtd;
- int res = 0, i;
-
- if (td->options & NAND_BBT_PERCHIP) {
- int offs = 0;
- for (i = 0; i < bbt->numchips; i++) {
- if (chip == -1 || chip == i)
- res = read_bbt(bbt, buf, td->pages[i],
- bbt->chipsize >> bbt->bbt_erase_shift,
- td, offs);
- if (res)
- return res;
- offs += bbt->chipsize >> bbt->bbt_erase_shift;
- }
- } else {
- res = read_bbt(bbt, buf, td->pages[0],
- mtd->size >> bbt->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 nand_bbt *bbt, 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(bbt->mtd, offs, len, &retlen, buf);
-}
-
-/**
- * scan_read_oob - [GENERIC] Scan data+OOB region to buffer
- * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf, loff_t offs,
- size_t len)
-{
- struct mtd_info *mtd = bbt->mtd;
- 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 nand_bbt *bbt, 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(bbt, buf, offs, td);
- else
- return scan_read_oob(bbt, buf, offs, len);
-}
-
-/* Scan write data with oob to flash */
-static int scan_write_bbt(struct nand_bbt *bbt, loff_t offs, size_t len,
- uint8_t *buf, uint8_t *oob)
-{
- struct mtd_info *mtd = bbt->mtd;
- 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 nand_bbt *bbt, struct nand_bbt_descr *td)
-{
- u32 ver_offs = td->veroffs;
-
- if (!(td->options & NAND_BBT_NO_OOB))
- ver_offs += bbt->mtd->writesize;
- return ver_offs;
-}
-
-/**
- * read_abs_bbts - [GENERIC] Read the bad block table(s) for all chips starting at a given page
- * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf,
- struct nand_bbt_descr *td, struct nand_bbt_descr *md)
-{
- struct mtd_info *mtd = bbt->mtd;
-
- /* Read the primary version, if available */
- if (td->options & NAND_BBT_VERSION) {
- scan_read(bbt, buf, (loff_t)td->pages[0] << bbt->page_shift,
- mtd->writesize, td);
- td->version[0] = buf[bbt_get_ver_offs(bbt, 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(bbt, buf, (loff_t)md->pages[0] << bbt->page_shift,
- mtd->writesize, md);
- md->version[0] = buf[bbt_get_ver_offs(bbt, md)];
- pr_info("Bad block table at page %d, version 0x%02X\n",
- md->pages[0], md->version[0]);
- }
-}
-
-/**
- * create_bbt - [GENERIC] Create a bad block table by scanning the device
- * @bbt: NAND BBT structure
- * @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 nand_bbt *bbt, int chip)
-{
- struct mtd_info *mtd = bbt->mtd;
- int i, startblock, numblocks;
- loff_t from;
-
- pr_info("Scanning device for bad blocks\n");
-
- if (chip == -1) {
- numblocks = mtd->size >> bbt->bbt_erase_shift;
- startblock = 0;
- from = 0;
- } else {
- if (chip >= bbt->numchips) {
- pr_warn("create_bbt(): chipnr (%d) > available chips (%d)\n",
- chip + 1, bbt->numchips);
- return -EINVAL;
- }
- numblocks = bbt->chipsize >> bbt->bbt_erase_shift;
- startblock = chip * numblocks;
- numblocks += startblock;
- from = (loff_t)startblock << bbt->bbt_erase_shift;
- }
-
- for (i = startblock; i < numblocks; i++) {
- int ret;
-
- ret = bbt->is_bad_bbm(mtd, from);
- if (ret < 0)
- return ret;
-
- if (ret) {
- bbt_mark_entry(bbt, 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 << bbt->bbt_erase_shift);
- }
- return 0;
-}
-
-/**
- * search_bbt - [GENERIC] scan the device for a specific bad block table
- * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf, struct nand_bbt_descr *td)
-{
- struct mtd_info *mtd = bbt->mtd;
- int i, chips;
- int startblock, block, dir;
- int scanlen = mtd->writesize + mtd->oobsize;
- int bbtblocks;
- int blocktopage = bbt->bbt_erase_shift - bbt->page_shift;
-
- /* Search direction top -> down? */
- if (td->options & NAND_BBT_LASTBLOCK) {
- startblock = (mtd->size >> bbt->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 = bbt->numchips;
- bbtblocks = bbt->chipsize >> bbt->bbt_erase_shift;
- startblock &= bbtblocks - 1;
- } else {
- chips = 1;
- bbtblocks = mtd->size >> bbt->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 << bbt->bbt_erase_shift;
-
- /* Read first page */
- scan_read(bbt, 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(bbt, td);
- td->version[i] = buf[offs];
- }
- break;
- }
- }
- startblock += bbt->chipsize >> bbt->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)
- * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf,
- struct nand_bbt_descr *td,
- struct nand_bbt_descr *md)
-{
- /* Search the primary table */
- search_bbt(bbt, buf, td);
-
- /* Search the mirror table */
- if (md)
- search_bbt(bbt, buf, md);
-}
-
-/**
- * write_bbt - [GENERIC] (Re)write the bad block table
- * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf,
- struct nand_bbt_descr *td, struct nand_bbt_descr *md,
- int chipsel)
-{
- struct mtd_info *mtd = bbt->mtd;
- int i, res, chip = 0;
- int bits, startblock, dir, 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)(bbt->chipsize >> bbt->bbt_erase_shift);
- /* Full device write or specific chip? */
- if (chipsel == -1) {
- nrchips = bbt->numchips;
- } else {
- nrchips = chipsel + 1;
- chip = chipsel;
- }
- } else {
- numblocks = (int)(mtd->size >> bbt->bbt_erase_shift);
- nrchips = 1;
- }
-
- /* Loop through the chips */
- for (; chip < nrchips; chip++) {
- /*
- * There was already a version of the table, reuse the page
- * This applies for absolute placement too, as we have the
- * page nr. in td->pages.
- */
- if (td->pages[chip] != -1) {
- page = td->pages[chip];
- goto write;
- }
-
- /*
- * 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(bbt, block)) {
- case BBT_BLOCK_WORN:
- case BBT_BLOCK_FACTORY_BAD:
- continue;
- }
- page = block <<
- (bbt->bbt_erase_shift - bbt->page_shift);
- /* Check, if the block is used by the mirror table */
- if (!md || md->pages[chip] != page)
- goto write;
- }
- pr_err("No space left to write bad block table\n");
- return -ENOSPC;
- write:
-
- /* 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) << bbt->page_shift;
-
- /* Must we save the block contents? */
- if (td->options & NAND_BBT_SAVECONTENT) {
- /* Make it block aligned */
- to &= ~(((loff_t)1 << bbt->bbt_erase_shift) - 1);
- len = 1 << bbt->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 >> bbt->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 >> bbt->page_shift);
- offs = pageoffs << bbt->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 >> bbt->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(bbt, chip * numblocks + i);
- /* Do not store the reserved bbt blocks! */
- buf[offs + (i >> sft)] &= ~(msk[dat] << sftcnt);
- }
-
- res = bbt->erase(mtd, to);
- if (res < 0)
- goto outerr;
-
- res = scan_write_bbt(bbt, to, len, buf,
- td->options & NAND_BBT_NO_OOB ? NULL :
- &buf[len]);
- if (res < 0)
- goto outerr;
-
- 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
- * @bbt: NAND BBT structure
- *
- * 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 nand_bbt *bbt)
-{
- return create_bbt(bbt, -1);
-}
-
-/**
- * check_create - [GENERIC] create and write bbt(s) if necessary
- * @bbt: NAND BBT structure
- * @buf: temporary buffer
- *
- * 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 nand_bbt *bbt, uint8_t *buf)
-{
- int i, chips, writeops, create, chipsel, res, res2;
- struct nand_bbt_descr *td = bbt->bbt_td;
- struct nand_bbt_descr *md = bbt->bbt_md;
- struct nand_bbt_descr *rd, *rd2;
-
- /* Do we have a bbt per chip? */
- if (td->options & NAND_BBT_PERCHIP)
- chips = bbt->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 (!(bbt->bbt_options & NAND_BBT_CREATE_EMPTY))
- create_bbt(bbt, chipsel);
-
- td->version[i] = 1;
- if (md)
- md->version[i] = 1;
- }
-
- /* Read back first? */
- if (rd) {
- res = read_abs_bbt(bbt, 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(bbt, 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(bbt, 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(bbt, buf, md, td, chipsel);
- if (res < 0)
- return res;
- }
- }
- return 0;
-}
-
-/**
- * mark_bbt_regions - [GENERIC] mark the bad block table regions
- * @bbt: NAND BBT 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 nand_bbt *bbt, struct nand_bbt_descr *td)
-{
- struct mtd_info *mtd = bbt->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 = bbt->numchips;
- nrblocks = (int)(bbt->chipsize >> bbt->bbt_erase_shift);
- } else {
- chips = 1;
- nrblocks = (int)(mtd->size >> bbt->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] >> (bbt->bbt_erase_shift - bbt->page_shift);
- oldval = bbt_get_entry(bbt, block);
- bbt_mark_entry(bbt, block, BBT_BLOCK_RESERVED);
- if ((oldval != BBT_BLOCK_RESERVED) &&
- td->reserved_block_code)
- nand_update_bbt(bbt, (loff_t)block <<
- bbt->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(bbt, block);
- bbt_mark_entry(bbt, 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(bbt, (loff_t)(block - 1) <<
- bbt->bbt_erase_shift);
- }
-}
-
-/**
- * verify_bbt_descr - verify the bad block description
- * @bbt: NAND BBT 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 nand_bbt *bbt, struct nand_bbt_descr *bd)
-{
- struct mtd_info *mtd = bbt->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((bbt->bbt_options & NAND_BBT_NO_OOB) &&
- !(bbt->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(!(bbt->bbt_options & NAND_BBT_USE_FLASH));
- BUG_ON(!(bbt->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 = bbt->chipsize >> bbt->bbt_erase_shift;
- else
- table_size = mtd->size >> bbt->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 << bbt->bbt_erase_shift));
-}
-
-/**
- * nand_scan_bbt - [NAND Interface] scan, find, read and maybe create bad block table(s)
- * @bbt: NAND BBT structure
- *
- * 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 nand_bbt *bbt)
-{
- struct mtd_info *mtd = bbt->mtd;
- int len, res = 0;
- uint8_t *buf;
- struct nand_bbt_descr *td = bbt->bbt_td;
- struct nand_bbt_descr *md = bbt->bbt_md;
-
- len = mtd->size >> (bbt->bbt_erase_shift + 2);
- /*
- * Allocate memory (2bit per block) and clear the memory bad block
- * table.
- */
- bbt->bbt = kzalloc(len, GFP_KERNEL);
- if (!bbt->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(bbt))) {
- pr_err("nand_bbt: can't scan flash and build the RAM-based BBT\n");
- goto err;
- }
- return 0;
- }
- verify_bbt_descr(bbt, td);
- verify_bbt_descr(bbt, md);
-
- /* Allocate a temporary buffer for one eraseblock incl. oob */
- len = (1 << bbt->bbt_erase_shift);
- len += (len >> bbt->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(bbt, buf, td, md);
- } else {
- /* Search the bad block table using a pattern in oob */
- search_read_bbts(bbt, buf, td, md);
- }
-
- res = check_create(bbt, buf);
- if (res)
- goto err;
-
- /* Prevent the bbt regions from erasing / writing */
- mark_bbt_region(bbt, td);
- if (md)
- mark_bbt_region(bbt, md);
-
- vfree(buf);
- return 0;
-
-err:
- kfree(bbt->bbt);
- bbt->bbt = NULL;
- return res;
-}
-
-/**
- * nand_update_bbt - update bad block table(s)
- * @bbt: NAND BBT structure
- * @offs: the offset of the newly marked block
- *
- * The function updates the bad block table(s).
- */
-static int nand_update_bbt(struct nand_bbt *bbt, loff_t offs)
-{
- struct mtd_info *mtd = bbt->mtd;
- int len, res = 0;
- int chip, chipsel;
- uint8_t *buf;
- struct nand_bbt_descr *td = bbt->bbt_td;
- struct nand_bbt_descr *md = bbt->bbt_md;
-
- if (!bbt->bbt || !td)
- return -EINVAL;
-
- /* Allocate a temporary buffer for one eraseblock incl. oob */
- len = (1 << bbt->bbt_erase_shift);
- len += (len >> bbt->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 >> bbt->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(bbt, 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(bbt, buf, md, td, chipsel);
- }
-
- out:
- kfree(buf);
- return res;
-}
-
-/* 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
-};
-
-/**
- * nand_bbt_init - [NAND BBT Interface] Initialize and locate/create a bad block
- * table
- * @bbt: NAND BBT structure
- *
- * This function selects the default bad block table support for the device and
- * scans for an existing table, or else creates one.
- */
-int nand_bbt_init(struct nand_bbt *bbt)
-{
- /* Is a flash based bad block table requested? */
- if (bbt->bbt_options & NAND_BBT_USE_FLASH) {
- /* Use the default pattern descriptors */
- if (!bbt->bbt_td) {
- if (bbt->bbt_options & NAND_BBT_NO_OOB) {
- bbt->bbt_td = &bbt_main_no_oob_descr;
- bbt->bbt_md = &bbt_mirror_no_oob_descr;
- } else {
- bbt->bbt_td = &bbt_main_descr;
- bbt->bbt_md = &bbt_mirror_descr;
- }
- }
- } else {
- bbt->bbt_td = NULL;
- bbt->bbt_md = NULL;
- }
-
- return nand_scan_bbt(bbt);
-}
-EXPORT_SYMBOL(nand_bbt_init);
-
-void nand_bbt_release(struct nand_bbt *bbt)
-{
- kfree(bbt->bbt);
-}
-EXPORT_SYMBOL(nand_bbt_release);
-
-/**
- * nand_bbt_isreserved - [NAND BBT Interface] Check if a block is reserved
- * @bbt: NAND BBT structure
- * @offs: offset in the device
- */
-int nand_bbt_isreserved(struct nand_bbt *bbt, loff_t offs)
-{
- int block;
-
- block = (int)(offs >> bbt->bbt_erase_shift);
- return bbt_get_entry(bbt, block) == BBT_BLOCK_RESERVED;
-}
-EXPORT_SYMBOL(nand_bbt_isreserved);
-
-/**
- * nand_bbt_isbad - [NAND BBT Interface] Check if a block is bad
- * @bbt: NAND BBT structure
- * @offs: offset in the device
- */
-int nand_bbt_isbad(struct nand_bbt *bbt, loff_t offs)
-{
- int block, res;
-
- block = (int)(offs >> bbt->bbt_erase_shift);
- res = bbt_get_entry(bbt, block);
-
- pr_debug("nand_bbt_isbad(): bbt info for offs 0x%08x: (block %d) 0x%02x\n",
- (unsigned int)offs, block, res);
-
- switch (res) {
- case BBT_BLOCK_GOOD:
- case BBT_BLOCK_RESERVED:
- return 0;
- case BBT_BLOCK_WORN:
- case BBT_BLOCK_FACTORY_BAD:
- default:
- return 1;
- }
-}
-EXPORT_SYMBOL(nand_bbt_isbad);
-
-/**
- * nand_bbt_update_mark - update mark in the BBT
- * @bbt: NAND BBT structure
- * @offs: offset of the bad block
- * @mark: block type mark
- */
-static int nand_bbt_update_mark(struct nand_bbt *bbt, loff_t offs, uint8_t mark)
-{
- int block, ret = 0;
-
- block = (int)(offs >> bbt->bbt_erase_shift);
-
- /* Mark bad block in memory */
- bbt_mark_entry(bbt, block, mark);
-
- /* Update flash-based bad block table */
- if (bbt->bbt_options & NAND_BBT_USE_FLASH)
- ret = nand_update_bbt(bbt, offs);
-
- return ret;
-}
-
-/**
- * nand_bbt_markbad - [NAND BBT Interface] Mark a block bad in the BBT
- * @bbt: NAND BBT structure
- * @offs: offset of the bad block
- */
-int nand_bbt_markbad(struct nand_bbt *bbt, loff_t offs)
-{
- return nand_bbt_update_mark(bbt, offs, BBT_BLOCK_WORN);
-}
-EXPORT_SYMBOL(nand_bbt_markbad);
-
-/**
- * nand_bbt_markbad_factory - [NAND BBT Interface] Mark a block as factory bad
- * in the BBT
- * @bbt: NAND BBT structure
- * @offs: offset of the bad block
- */
-int nand_bbt_markbad_factory(struct nand_bbt *bbt, loff_t offs)
-{
- return nand_bbt_update_mark(bbt, offs, BBT_BLOCK_FACTORY_BAD);
-}
-EXPORT_SYMBOL(nand_bbt_markbad_factory);
diff --git a/drivers/mtd/nand_bbt.c b/drivers/mtd/nand_bbt.c
new file mode 100644
index 0000000..47c1084
--- /dev/null
+++ b/drivers/mtd/nand_bbt.c
@@ -0,0 +1,1289 @@
+/*
+ * Overview:
+ * Bad block table support for the NAND driver
+ *
+ * Copyright ? 2004 Thomas Gleixner (tglx at 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/nand_bbt.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 nand_bbt *bbt, loff_t offs);
+
+static inline uint8_t bbt_get_entry(struct nand_bbt *bbt, int block)
+{
+ uint8_t entry = bbt->bbt[block >> BBT_ENTRY_SHIFT];
+ entry >>= (block & BBT_ENTRY_MASK) * 2;
+ return entry & BBT_ENTRY_MASK;
+}
+
+static inline void bbt_mark_entry(struct nand_bbt *bbt, int block,
+ uint8_t mark)
+{
+ uint8_t msk = (mark & BBT_ENTRY_MASK) << ((block & BBT_ENTRY_MASK) * 2);
+ bbt->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;
+}
+
+/**
+ * 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
+ * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf, int page, int num,
+ struct nand_bbt_descr *td, int offs)
+{
+ struct mtd_info *mtd = bbt->mtd;
+ int res, ret = 0, i, j, act = 0;
+ 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) << bbt->page_shift;
+
+ while (totlen) {
+ len = min(totlen, (size_t)(1 << bbt->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) <<
+ bbt->bbt_erase_shift);
+ bbt_mark_entry(bbt, 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) <<
+ bbt->bbt_erase_shift);
+ /* Factory marked bad or worn out? */
+ if (tmp == 0)
+ bbt_mark_entry(bbt, offs + act,
+ BBT_BLOCK_FACTORY_BAD);
+ else
+ bbt_mark_entry(bbt, 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
+ * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf, struct nand_bbt_descr *td, int chip)
+{
+ struct mtd_info *mtd = bbt->mtd;
+ int res = 0, i;
+
+ if (td->options & NAND_BBT_PERCHIP) {
+ int offs = 0;
+ for (i = 0; i < bbt->numchips; i++) {
+ if (chip == -1 || chip == i)
+ res = read_bbt(bbt, buf, td->pages[i],
+ bbt->chipsize >> bbt->bbt_erase_shift,
+ td, offs);
+ if (res)
+ return res;
+ offs += bbt->chipsize >> bbt->bbt_erase_shift;
+ }
+ } else {
+ res = read_bbt(bbt, buf, td->pages[0],
+ mtd->size >> bbt->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 nand_bbt *bbt, 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(bbt->mtd, offs, len, &retlen, buf);
+}
+
+/**
+ * scan_read_oob - [GENERIC] Scan data+OOB region to buffer
+ * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf, loff_t offs,
+ size_t len)
+{
+ struct mtd_info *mtd = bbt->mtd;
+ 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 nand_bbt *bbt, 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(bbt, buf, offs, td);
+ else
+ return scan_read_oob(bbt, buf, offs, len);
+}
+
+/* Scan write data with oob to flash */
+static int scan_write_bbt(struct nand_bbt *bbt, loff_t offs, size_t len,
+ uint8_t *buf, uint8_t *oob)
+{
+ struct mtd_info *mtd = bbt->mtd;
+ 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 nand_bbt *bbt, struct nand_bbt_descr *td)
+{
+ u32 ver_offs = td->veroffs;
+
+ if (!(td->options & NAND_BBT_NO_OOB))
+ ver_offs += bbt->mtd->writesize;
+ return ver_offs;
+}
+
+/**
+ * read_abs_bbts - [GENERIC] Read the bad block table(s) for all chips starting at a given page
+ * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf,
+ struct nand_bbt_descr *td, struct nand_bbt_descr *md)
+{
+ struct mtd_info *mtd = bbt->mtd;
+
+ /* Read the primary version, if available */
+ if (td->options & NAND_BBT_VERSION) {
+ scan_read(bbt, buf, (loff_t)td->pages[0] << bbt->page_shift,
+ mtd->writesize, td);
+ td->version[0] = buf[bbt_get_ver_offs(bbt, 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(bbt, buf, (loff_t)md->pages[0] << bbt->page_shift,
+ mtd->writesize, md);
+ md->version[0] = buf[bbt_get_ver_offs(bbt, md)];
+ pr_info("Bad block table at page %d, version 0x%02X\n",
+ md->pages[0], md->version[0]);
+ }
+}
+
+/**
+ * create_bbt - [GENERIC] Create a bad block table by scanning the device
+ * @bbt: NAND BBT structure
+ * @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 nand_bbt *bbt, int chip)
+{
+ struct mtd_info *mtd = bbt->mtd;
+ int i, startblock, numblocks;
+ loff_t from;
+
+ pr_info("Scanning device for bad blocks\n");
+
+ if (chip == -1) {
+ numblocks = mtd->size >> bbt->bbt_erase_shift;
+ startblock = 0;
+ from = 0;
+ } else {
+ if (chip >= bbt->numchips) {
+ pr_warn("create_bbt(): chipnr (%d) > available chips (%d)\n",
+ chip + 1, bbt->numchips);
+ return -EINVAL;
+ }
+ numblocks = bbt->chipsize >> bbt->bbt_erase_shift;
+ startblock = chip * numblocks;
+ numblocks += startblock;
+ from = (loff_t)startblock << bbt->bbt_erase_shift;
+ }
+
+ for (i = startblock; i < numblocks; i++) {
+ int ret;
+
+ ret = bbt->is_bad_bbm(mtd, from);
+ if (ret < 0)
+ return ret;
+
+ if (ret) {
+ bbt_mark_entry(bbt, 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 << bbt->bbt_erase_shift);
+ }
+ return 0;
+}
+
+/**
+ * search_bbt - [GENERIC] scan the device for a specific bad block table
+ * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf, struct nand_bbt_descr *td)
+{
+ struct mtd_info *mtd = bbt->mtd;
+ int i, chips;
+ int startblock, block, dir;
+ int scanlen = mtd->writesize + mtd->oobsize;
+ int bbtblocks;
+ int blocktopage = bbt->bbt_erase_shift - bbt->page_shift;
+
+ /* Search direction top -> down? */
+ if (td->options & NAND_BBT_LASTBLOCK) {
+ startblock = (mtd->size >> bbt->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 = bbt->numchips;
+ bbtblocks = bbt->chipsize >> bbt->bbt_erase_shift;
+ startblock &= bbtblocks - 1;
+ } else {
+ chips = 1;
+ bbtblocks = mtd->size >> bbt->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 << bbt->bbt_erase_shift;
+
+ /* Read first page */
+ scan_read(bbt, 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(bbt, td);
+ td->version[i] = buf[offs];
+ }
+ break;
+ }
+ }
+ startblock += bbt->chipsize >> bbt->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)
+ * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf,
+ struct nand_bbt_descr *td,
+ struct nand_bbt_descr *md)
+{
+ /* Search the primary table */
+ search_bbt(bbt, buf, td);
+
+ /* Search the mirror table */
+ if (md)
+ search_bbt(bbt, buf, md);
+}
+
+/**
+ * write_bbt - [GENERIC] (Re)write the bad block table
+ * @bbt: NAND BBT 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 nand_bbt *bbt, uint8_t *buf,
+ struct nand_bbt_descr *td, struct nand_bbt_descr *md,
+ int chipsel)
+{
+ struct mtd_info *mtd = bbt->mtd;
+ int i, res, chip = 0;
+ int bits, startblock, dir, 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)(bbt->chipsize >> bbt->bbt_erase_shift);
+ /* Full device write or specific chip? */
+ if (chipsel == -1) {
+ nrchips = bbt->numchips;
+ } else {
+ nrchips = chipsel + 1;
+ chip = chipsel;
+ }
+ } else {
+ numblocks = (int)(mtd->size >> bbt->bbt_erase_shift);
+ nrchips = 1;
+ }
+
+ /* Loop through the chips */
+ for (; chip < nrchips; chip++) {
+ /*
+ * There was already a version of the table, reuse the page
+ * This applies for absolute placement too, as we have the
+ * page nr. in td->pages.
+ */
+ if (td->pages[chip] != -1) {
+ page = td->pages[chip];
+ goto write;
+ }
+
+ /*
+ * 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(bbt, block)) {
+ case BBT_BLOCK_WORN:
+ case BBT_BLOCK_FACTORY_BAD:
+ continue;
+ }
+ page = block <<
+ (bbt->bbt_erase_shift - bbt->page_shift);
+ /* Check, if the block is used by the mirror table */
+ if (!md || md->pages[chip] != page)
+ goto write;
+ }
+ pr_err("No space left to write bad block table\n");
+ return -ENOSPC;
+ write:
+
+ /* 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) << bbt->page_shift;
+
+ /* Must we save the block contents? */
+ if (td->options & NAND_BBT_SAVECONTENT) {
+ /* Make it block aligned */
+ to &= ~(((loff_t)1 << bbt->bbt_erase_shift) - 1);
+ len = 1 << bbt->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 >> bbt->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 >> bbt->page_shift);
+ offs = pageoffs << bbt->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 >> bbt->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(bbt, chip * numblocks + i);
+ /* Do not store the reserved bbt blocks! */
+ buf[offs + (i >> sft)] &= ~(msk[dat] << sftcnt);
+ }
+
+ res = bbt->erase(mtd, to);
+ if (res < 0)
+ goto outerr;
+
+ res = scan_write_bbt(bbt, to, len, buf,
+ td->options & NAND_BBT_NO_OOB ? NULL :
+ &buf[len]);
+ if (res < 0)
+ goto outerr;
+
+ 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
+ * @bbt: NAND BBT structure
+ *
+ * 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 nand_bbt *bbt)
+{
+ return create_bbt(bbt, -1);
+}
+
+/**
+ * check_create - [GENERIC] create and write bbt(s) if necessary
+ * @bbt: NAND BBT structure
+ * @buf: temporary buffer
+ *
+ * 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 nand_bbt *bbt, uint8_t *buf)
+{
+ int i, chips, writeops, create, chipsel, res, res2;
+ struct nand_bbt_descr *td = bbt->bbt_td;
+ struct nand_bbt_descr *md = bbt->bbt_md;
+ struct nand_bbt_descr *rd, *rd2;
+
+ /* Do we have a bbt per chip? */
+ if (td->options & NAND_BBT_PERCHIP)
+ chips = bbt->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 (!(bbt->bbt_options & NAND_BBT_CREATE_EMPTY))
+ create_bbt(bbt, chipsel);
+
+ td->version[i] = 1;
+ if (md)
+ md->version[i] = 1;
+ }
+
+ /* Read back first? */
+ if (rd) {
+ res = read_abs_bbt(bbt, 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(bbt, 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(bbt, 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(bbt, buf, md, td, chipsel);
+ if (res < 0)
+ return res;
+ }
+ }
+ return 0;
+}
+
+/**
+ * mark_bbt_regions - [GENERIC] mark the bad block table regions
+ * @bbt: NAND BBT 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 nand_bbt *bbt, struct nand_bbt_descr *td)
+{
+ struct mtd_info *mtd = bbt->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 = bbt->numchips;
+ nrblocks = (int)(bbt->chipsize >> bbt->bbt_erase_shift);
+ } else {
+ chips = 1;
+ nrblocks = (int)(mtd->size >> bbt->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] >> (bbt->bbt_erase_shift - bbt->page_shift);
+ oldval = bbt_get_entry(bbt, block);
+ bbt_mark_entry(bbt, block, BBT_BLOCK_RESERVED);
+ if ((oldval != BBT_BLOCK_RESERVED) &&
+ td->reserved_block_code)
+ nand_update_bbt(bbt, (loff_t)block <<
+ bbt->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(bbt, block);
+ bbt_mark_entry(bbt, 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(bbt, (loff_t)(block - 1) <<
+ bbt->bbt_erase_shift);
+ }
+}
+
+/**
+ * verify_bbt_descr - verify the bad block description
+ * @bbt: NAND BBT 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 nand_bbt *bbt, struct nand_bbt_descr *bd)
+{
+ struct mtd_info *mtd = bbt->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((bbt->bbt_options & NAND_BBT_NO_OOB) &&
+ !(bbt->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(!(bbt->bbt_options & NAND_BBT_USE_FLASH));
+ BUG_ON(!(bbt->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 = bbt->chipsize >> bbt->bbt_erase_shift;
+ else
+ table_size = mtd->size >> bbt->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 << bbt->bbt_erase_shift));
+}
+
+/**
+ * nand_scan_bbt - [NAND Interface] scan, find, read and maybe create bad block table(s)
+ * @bbt: NAND BBT structure
+ *
+ * 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 nand_bbt *bbt)
+{
+ struct mtd_info *mtd = bbt->mtd;
+ int len, res = 0;
+ uint8_t *buf;
+ struct nand_bbt_descr *td = bbt->bbt_td;
+ struct nand_bbt_descr *md = bbt->bbt_md;
+
+ len = mtd->size >> (bbt->bbt_erase_shift + 2);
+ /*
+ * Allocate memory (2bit per block) and clear the memory bad block
+ * table.
+ */
+ bbt->bbt = kzalloc(len, GFP_KERNEL);
+ if (!bbt->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(bbt))) {
+ pr_err("nand_bbt: can't scan flash and build the RAM-based BBT\n");
+ goto err;
+ }
+ return 0;
+ }
+ verify_bbt_descr(bbt, td);
+ verify_bbt_descr(bbt, md);
+
+ /* Allocate a temporary buffer for one eraseblock incl. oob */
+ len = (1 << bbt->bbt_erase_shift);
+ len += (len >> bbt->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(bbt, buf, td, md);
+ } else {
+ /* Search the bad block table using a pattern in oob */
+ search_read_bbts(bbt, buf, td, md);
+ }
+
+ res = check_create(bbt, buf);
+ if (res)
+ goto err;
+
+ /* Prevent the bbt regions from erasing / writing */
+ mark_bbt_region(bbt, td);
+ if (md)
+ mark_bbt_region(bbt, md);
+
+ vfree(buf);
+ return 0;
+
+err:
+ kfree(bbt->bbt);
+ bbt->bbt = NULL;
+ return res;
+}
+
+/**
+ * nand_update_bbt - update bad block table(s)
+ * @bbt: NAND BBT structure
+ * @offs: the offset of the newly marked block
+ *
+ * The function updates the bad block table(s).
+ */
+static int nand_update_bbt(struct nand_bbt *bbt, loff_t offs)
+{
+ struct mtd_info *mtd = bbt->mtd;
+ int len, res = 0;
+ int chip, chipsel;
+ uint8_t *buf;
+ struct nand_bbt_descr *td = bbt->bbt_td;
+ struct nand_bbt_descr *md = bbt->bbt_md;
+
+ if (!bbt->bbt || !td)
+ return -EINVAL;
+
+ /* Allocate a temporary buffer for one eraseblock incl. oob */
+ len = (1 << bbt->bbt_erase_shift);
+ len += (len >> bbt->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 >> bbt->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(bbt, 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(bbt, buf, md, td, chipsel);
+ }
+
+ out:
+ kfree(buf);
+ return res;
+}
+
+/* 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
+};
+
+/**
+ * nand_bbt_init - [NAND BBT Interface] Initialize and locate/create a bad block
+ * table
+ * @bbt: NAND BBT structure
+ *
+ * This function selects the default bad block table support for the device and
+ * scans for an existing table, or else creates one.
+ */
+int nand_bbt_init(struct nand_bbt *bbt)
+{
+ /* Is a flash based bad block table requested? */
+ if (bbt->bbt_options & NAND_BBT_USE_FLASH) {
+ /* Use the default pattern descriptors */
+ if (!bbt->bbt_td) {
+ if (bbt->bbt_options & NAND_BBT_NO_OOB) {
+ bbt->bbt_td = &bbt_main_no_oob_descr;
+ bbt->bbt_md = &bbt_mirror_no_oob_descr;
+ } else {
+ bbt->bbt_td = &bbt_main_descr;
+ bbt->bbt_md = &bbt_mirror_descr;
+ }
+ }
+ } else {
+ bbt->bbt_td = NULL;
+ bbt->bbt_md = NULL;
+ }
+
+ return nand_scan_bbt(bbt);
+}
+EXPORT_SYMBOL(nand_bbt_init);
+
+void nand_bbt_release(struct nand_bbt *bbt)
+{
+ kfree(bbt->bbt);
+}
+EXPORT_SYMBOL(nand_bbt_release);
+
+/**
+ * nand_bbt_isreserved - [NAND BBT Interface] Check if a block is reserved
+ * @bbt: NAND BBT structure
+ * @offs: offset in the device
+ */
+int nand_bbt_isreserved(struct nand_bbt *bbt, loff_t offs)
+{
+ int block;
+
+ block = (int)(offs >> bbt->bbt_erase_shift);
+ return bbt_get_entry(bbt, block) == BBT_BLOCK_RESERVED;
+}
+EXPORT_SYMBOL(nand_bbt_isreserved);
+
+/**
+ * nand_bbt_isbad - [NAND BBT Interface] Check if a block is bad
+ * @bbt: NAND BBT structure
+ * @offs: offset in the device
+ */
+int nand_bbt_isbad(struct nand_bbt *bbt, loff_t offs)
+{
+ int block, res;
+
+ block = (int)(offs >> bbt->bbt_erase_shift);
+ res = bbt_get_entry(bbt, block);
+
+ pr_debug("nand_bbt_isbad(): bbt info for offs 0x%08x: (block %d) 0x%02x\n",
+ (unsigned int)offs, block, res);
+
+ switch (res) {
+ case BBT_BLOCK_GOOD:
+ case BBT_BLOCK_RESERVED:
+ return 0;
+ case BBT_BLOCK_WORN:
+ case BBT_BLOCK_FACTORY_BAD:
+ default:
+ return 1;
+ }
+}
+EXPORT_SYMBOL(nand_bbt_isbad);
+
+/**
+ * nand_bbt_update_mark - update mark in the BBT
+ * @bbt: NAND BBT structure
+ * @offs: offset of the bad block
+ * @mark: block type mark
+ */
+static int nand_bbt_update_mark(struct nand_bbt *bbt, loff_t offs, uint8_t mark)
+{
+ int block, ret = 0;
+
+ block = (int)(offs >> bbt->bbt_erase_shift);
+
+ /* Mark bad block in memory */
+ bbt_mark_entry(bbt, block, mark);
+
+ /* Update flash-based bad block table */
+ if (bbt->bbt_options & NAND_BBT_USE_FLASH)
+ ret = nand_update_bbt(bbt, offs);
+
+ return ret;
+}
+
+/**
+ * nand_bbt_markbad - [NAND BBT Interface] Mark a block bad in the BBT
+ * @bbt: NAND BBT structure
+ * @offs: offset of the bad block
+ */
+int nand_bbt_markbad(struct nand_bbt *bbt, loff_t offs)
+{
+ return nand_bbt_update_mark(bbt, offs, BBT_BLOCK_WORN);
+}
+EXPORT_SYMBOL(nand_bbt_markbad);
+
+/**
+ * nand_bbt_markbad_factory - [NAND BBT Interface] Mark a block as factory bad
+ * in the BBT
+ * @bbt: NAND BBT structure
+ * @offs: offset of the bad block
+ */
+int nand_bbt_markbad_factory(struct nand_bbt *bbt, loff_t offs)
+{
+ return nand_bbt_update_mark(bbt, offs, BBT_BLOCK_FACTORY_BAD);
+}
+EXPORT_SYMBOL(nand_bbt_markbad_factory);
--
1.9.1
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