aboutsummaryrefslogtreecommitdiff
path: root/drivers/mtd/nand/nand_bbt.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/mtd/nand/nand_bbt.c')
-rw-r--r--drivers/mtd/nand/nand_bbt.c250
1 files changed, 214 insertions, 36 deletions
diff --git a/drivers/mtd/nand/nand_bbt.c b/drivers/mtd/nand/nand_bbt.c
index 5fedf4a74f1..586b981f0e6 100644
--- a/drivers/mtd/nand/nand_bbt.c
+++ b/drivers/mtd/nand/nand_bbt.c
@@ -13,28 +13,37 @@
* 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 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
- * than the mirror bbt is used to build the memory based bbt.
+ * depending on the options in the BBT descriptor(s). If no flash based BBT
+ * (NAND_USE_FLASH_BBT) 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 than 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- * If one of the bbt's is out of date or does not exist it is (re)created.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
+ * If one of the BBTs is out of date or does not exist it is (re)created.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
+ * For manufacturer created BBTs like the one found on M-SYS DOC devices
+ * the BBT is searched and read but never created
*
- * The autogenerated bad block table is located in the last good blocks
+ * 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.
+ * 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_USE_FLASH_BBT_NO_OOB should be used: 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
+ * 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
@@ -59,6 +68,16 @@
#include <linux/delay.h>
#include <linux/vmalloc.h>
+static int check_pattern_no_oob(uint8_t *buf, struct nand_bbt_descr *td)
+{
+ int ret;
+
+ ret = memcmp(buf, td->pattern, td->len);
+ if (!ret)
+ return ret;
+ return -1;
+}
+
/**
* check_pattern - [GENERIC] check if a pattern is in the buffer
* @buf: the buffer to search
@@ -77,6 +96,9 @@ static int check_pattern(uint8_t *buf, int len, int paglen, struct nand_bbt_desc
int i, end = 0;
uint8_t *p = buf;
+ if (td->options & NAND_BBT_NO_OOB)
+ return check_pattern_no_oob(buf, td);
+
end = paglen + td->offs;
if (td->options & NAND_BBT_SCANEMPTY) {
for (i = 0; i < end; i++) {
@@ -156,32 +178,63 @@ static int check_short_pattern(uint8_t *buf, struct nand_bbt_descr *td)
}
/**
+ * 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 markeris 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
- * @bits: number of bits per block
+ * @td: the bbt describtion table
* @offs: offset in the memory table
- * @reserved_block_code: Pattern to identify reserved blocks
*
* Read the bad block table starting from page.
*
*/
static int read_bbt(struct mtd_info *mtd, uint8_t *buf, int page, int num,
- int bits, int offs, int reserved_block_code)
+ struct nand_bbt_descr *td, int offs)
{
int res, i, j, act = 0;
struct nand_chip *this = mtd->priv;
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 (retlen != len) {
@@ -238,20 +291,21 @@ static int read_abs_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_desc
{
struct nand_chip *this = mtd->priv;
int res = 0, i;
- int bits;
- bits = td->options & NAND_BBT_NRBITS_MSK;
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, bits, offs, td->reserved_block_code);
+ 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 + 2);
}
} else {
- res = read_bbt (mtd, buf, td->pages[0], mtd->size >> this->bbt_erase_shift, bits, 0, td->reserved_block_code);
+ res = read_bbt(mtd, buf, td->pages[0],
+ mtd->size >> this->bbt_erase_shift, td, 0);
if (res)
return res;
}
@@ -259,9 +313,25 @@ static int read_abs_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_desc
}
/*
+ * BBT marker is in the first page, no OOB.
+ */
+static int scan_read_raw_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 raw data from flash
*/
-static int scan_read_raw(struct mtd_info *mtd, uint8_t *buf, loff_t offs,
+static int scan_read_raw_oob(struct mtd_info *mtd, uint8_t *buf, loff_t offs,
size_t len)
{
struct mtd_oob_ops ops;
@@ -294,6 +364,15 @@ static int scan_read_raw(struct mtd_info *mtd, uint8_t *buf, loff_t offs,
return 0;
}
+static int scan_read_raw(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_raw_data(mtd, buf, offs, td);
+ else
+ return scan_read_raw_oob(mtd, buf, offs, len);
+}
+
/*
* Scan write data with oob to flash
*/
@@ -312,6 +391,15 @@ static int scan_write_bbt(struct mtd_info *mtd, loff_t offs, size_t 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
@@ -331,8 +419,8 @@ static int read_abs_bbts(struct mtd_info *mtd, uint8_t *buf,
/* Read the primary version, if available */
if (td->options & NAND_BBT_VERSION) {
scan_read_raw(mtd, buf, (loff_t)td->pages[0] << this->page_shift,
- mtd->writesize);
- td->version[0] = buf[mtd->writesize + td->veroffs];
+ mtd->writesize, td);
+ td->version[0] = buf[bbt_get_ver_offs(mtd, td)];
printk(KERN_DEBUG "Bad block table at page %d, version 0x%02X\n",
td->pages[0], td->version[0]);
}
@@ -340,8 +428,8 @@ static int read_abs_bbts(struct mtd_info *mtd, uint8_t *buf,
/* Read the mirror version, if available */
if (md && (md->options & NAND_BBT_VERSION)) {
scan_read_raw(mtd, buf, (loff_t)md->pages[0] << this->page_shift,
- mtd->writesize);
- md->version[0] = buf[mtd->writesize + md->veroffs];
+ mtd->writesize, td);
+ md->version[0] = buf[bbt_get_ver_offs(mtd, md)];
printk(KERN_DEBUG "Bad block table at page %d, version 0x%02X\n",
md->pages[0], md->version[0]);
}
@@ -357,7 +445,7 @@ static int scan_block_full(struct mtd_info *mtd, struct nand_bbt_descr *bd,
{
int ret, j;
- ret = scan_read_raw(mtd, buf, offs, readlen);
+ ret = scan_read_raw_oob(mtd, buf, offs, readlen);
if (ret)
return ret;
@@ -464,6 +552,8 @@ static int create_bbt(struct mtd_info *mtd, uint8_t *buf,
for (i = startblock; i < numblocks;) {
int ret;
+ BUG_ON(bd->options & NAND_BBT_NO_OOB);
+
if (bd->options & NAND_BBT_SCANALLPAGES)
ret = scan_block_full(mtd, bd, from, buf, readlen,
scanlen, len);
@@ -545,11 +635,12 @@ static int search_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
loff_t offs = (loff_t)actblock << this->bbt_erase_shift;
/* Read first page */
- scan_read_raw(mtd, buf, offs, mtd->writesize);
+ scan_read_raw(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) {
- td->version[i] = buf[mtd->writesize + td->veroffs];
+ offs = bbt_get_ver_offs(mtd, td);
+ td->version[i] = buf[offs];
}
break;
}
@@ -733,12 +824,26 @@ static int write_bbt(struct mtd_info *mtd, uint8_t *buf,
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 = (len + (mtd->writesize - 1)) &
- ~(mtd->writesize - 1);
+ len = ALIGN(len, mtd->writesize);
/* Preset the buffer with 0xff */
memset(buf, 0xff, len +
(len >> this->page_shift)* mtd->oobsize);
@@ -772,7 +877,9 @@ static int write_bbt(struct mtd_info *mtd, uint8_t *buf,
if (res < 0)
goto outerr;
- res = scan_write_bbt(mtd, to, len, buf, &buf[len]);
+ res = scan_write_bbt(mtd, to, len, buf,
+ td->options & NAND_BBT_NO_OOB ? NULL :
+ &buf[len]);
if (res < 0)
goto outerr;
@@ -892,7 +999,8 @@ static int check_create(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_desc
continue;
/* Create the table in memory by scanning the chip(s) */
- create_bbt(mtd, buf, bd, chipsel);
+ if (!(this->options & NAND_CREATE_EMPTY_BBT))
+ create_bbt(mtd, buf, bd, chipsel);
td->version[i] = 1;
if (md)
@@ -983,6 +1091,49 @@ static void mark_bbt_region(struct mtd_info *mtd, struct nand_bbt_descr *td)
}
/**
+ * verify_bbt_descr - verify the bad block description
+ * @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->priv;
+ u32 pattern_len = bd->len;
+ u32 bits = bd->options & NAND_BBT_NRBITS_MSK;
+ u32 table_size;
+
+ if (!bd)
+ return;
+ BUG_ON((this->options & NAND_USE_FLASH_BBT_NO_OOB) &&
+ !(this->options & NAND_USE_FLASH_BBT));
+ BUG_ON(!bits);
+
+ if (bd->options & NAND_BBT_VERSION)
+ pattern_len++;
+
+ if (bd->options & NAND_BBT_NO_OOB) {
+ BUG_ON(!(this->options & NAND_USE_FLASH_BBT));
+ BUG_ON(!(this->options & NAND_USE_FLASH_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
@@ -1023,6 +1174,8 @@ int nand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd)
}
return res;
}
+ 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);
@@ -1166,6 +1319,26 @@ static struct nand_bbt_descr bbt_mirror_descr = {
.pattern = mirror_pattern
};
+static struct nand_bbt_descr bbt_main_no_bbt_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 = 4,
+ .pattern = bbt_pattern
+};
+
+static struct nand_bbt_descr bbt_mirror_no_bbt_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 = 4,
+ .pattern = mirror_pattern
+};
+
#define BBT_SCAN_OPTIONS (NAND_BBT_SCANLASTPAGE | NAND_BBT_SCAN2NDPAGE | \
NAND_BBT_SCANBYTE1AND6)
/**
@@ -1236,8 +1409,13 @@ int nand_default_bbt(struct mtd_info *mtd)
if (this->options & NAND_USE_FLASH_BBT) {
/* Use the default pattern descriptors */
if (!this->bbt_td) {
- this->bbt_td = &bbt_main_descr;
- this->bbt_md = &bbt_mirror_descr;
+ if (this->options & NAND_USE_FLASH_BBT_NO_OOB) {
+ this->bbt_td = &bbt_main_no_bbt_descr;
+ this->bbt_md = &bbt_mirror_no_bbt_descr;
+ } else {
+ this->bbt_td = &bbt_main_descr;
+ this->bbt_md = &bbt_mirror_descr;
+ }
}
if (!this->badblock_pattern) {
this->badblock_pattern = (mtd->writesize > 512) ? &largepage_flashbased : &smallpage_flashbased;