[MTD] OneNAND: Single bit error detection
Idea from Jarkko Lavinen
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index bef4f26..fc84ddc 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -331,9 +331,12 @@
if (interrupt & ONENAND_INT_READ) {
ecc = this->read_word(this->base + ONENAND_REG_ECC_STATUS);
- if (ecc & ONENAND_ECC_2BIT_ALL) {
+ if (ecc) {
DEBUG(MTD_DEBUG_LEVEL0, "onenand_wait: ECC error = 0x%04x\n", ecc);
- return -EBADMSG;
+ if (ecc & ONENAND_ECC_2BIT_ALL)
+ mtd->ecc_stats.failed++;
+ else if (ecc & ONENAND_ECC_1BIT_ALL)
+ mtd->ecc_stats.corrected++;
}
}
@@ -715,6 +718,7 @@
size_t *retlen, u_char *buf)
{
struct onenand_chip *this = mtd->priv;
+ struct mtd_ecc_stats stats;
int read = 0, column;
int thislen;
int ret = 0;
@@ -733,6 +737,7 @@
/* TODO handling oob */
+ stats = mtd->ecc_stats;
while (read < len) {
thislen = min_t(int, mtd->writesize, len - read);
@@ -774,7 +779,11 @@
* retlen == desired len and result == -EBADMSG
*/
*retlen = read;
- return ret;
+
+ if (mtd->ecc_stats.failed - stats.failed)
+ return -EBADMSG;
+
+ return mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
}
/**
@@ -1390,7 +1399,6 @@
return onenand_do_lock_cmd(mtd, ofs, len, ONENAND_CMD_LOCK);
}
-
/**
* onenand_unlock - [MTD Interface] Unlock block(s)
* @param mtd MTD device structure
@@ -1900,7 +1908,7 @@
/* Read manufacturer and device IDs from Register */
maf_id = this->read_word(this->base + ONENAND_REG_MANUFACTURER_ID);
dev_id = this->read_word(this->base + ONENAND_REG_DEVICE_ID);
- ver_id= this->read_word(this->base + ONENAND_REG_VERSION_ID);
+ ver_id = this->read_word(this->base + ONENAND_REG_VERSION_ID);
/* Check OneNAND device */
if (maf_id != bram_maf_id || dev_id != bram_dev_id)
diff --git a/drivers/mtd/onenand/onenand_bbt.c b/drivers/mtd/onenand/onenand_bbt.c
index 1b00dac..c8067b8 100644
--- a/drivers/mtd/onenand/onenand_bbt.c
+++ b/drivers/mtd/onenand/onenand_bbt.c
@@ -100,6 +100,7 @@
bbm->bbt[i >> 3] |= 0x03 << (i & 0x6);
printk(KERN_WARNING "Bad eraseblock %d at 0x%08x\n",
i >> 1, (unsigned int) from);
+ mtd->ecc_stats.badblocks++;
break;
}
}
diff --git a/include/linux/mtd/onenand_regs.h b/include/linux/mtd/onenand_regs.h
index 9e409fe..e31c8f5 100644
--- a/include/linux/mtd/onenand_regs.h
+++ b/include/linux/mtd/onenand_regs.h
@@ -179,6 +179,7 @@
* ECC Status Reigser FF00h (R)
*/
#define ONENAND_ECC_1BIT (1 << 0)
+#define ONENAND_ECC_1BIT_ALL (0x5555)
#define ONENAND_ECC_2BIT (1 << 1)
#define ONENAND_ECC_2BIT_ALL (0xAAAA)