aboutsummaryrefslogtreecommitdiff
path: root/drivers/mtd/nand/nand_ecc.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/mtd/nand/nand_ecc.c')
-rw-r--r--drivers/mtd/nand/nand_ecc.c73
1 files changed, 52 insertions, 21 deletions
diff --git a/drivers/mtd/nand/nand_ecc.c b/drivers/mtd/nand/nand_ecc.c
index 868147acce2..97c4c0216c9 100644
--- a/drivers/mtd/nand/nand_ecc.c
+++ b/drivers/mtd/nand/nand_ecc.c
@@ -55,8 +55,7 @@ struct mtd_info;
#define MODULE_AUTHOR(x) /* x */
#define MODULE_DESCRIPTION(x) /* x */
-#define printk printf
-#define KERN_ERR ""
+#define pr_err printf
#endif
/*
@@ -110,7 +109,7 @@ static const char bitsperbyte[256] = {
/*
* addressbits is a lookup table to filter out the bits from the xor-ed
- * ecc data that identify the faulty location.
+ * ECC data that identify the faulty location.
* this is only used for repairing parity
* see the comments in nand_correct_data for more details
*/
@@ -150,20 +149,19 @@ static const char addressbits[256] = {
};
/**
- * nand_calculate_ecc - [NAND Interface] Calculate 3-byte ECC for 256/512-byte
+ * __nand_calculate_ecc - [NAND Interface] Calculate 3-byte ECC for 256/512-byte
* block
- * @mtd: MTD block structure
* @buf: input buffer with raw data
+ * @eccsize: data bytes per ECC step (256 or 512)
* @code: output buffer with ECC
*/
-int nand_calculate_ecc(struct mtd_info *mtd, const unsigned char *buf,
+void __nand_calculate_ecc(const unsigned char *buf, unsigned int eccsize,
unsigned char *code)
{
int i;
const uint32_t *bp = (uint32_t *)buf;
/* 256 or 512 bytes/ecc */
- const uint32_t eccsize_mult =
- (((struct nand_chip *)mtd->priv)->ecc.size) >> 8;
+ const uint32_t eccsize_mult = eccsize >> 8;
uint32_t cur; /* current value in buffer */
/* rp0..rp15..rp17 are the various accumulated parities (per byte) */
uint32_t rp0, rp1, rp2, rp3, rp4, rp5, rp6, rp7;
@@ -349,7 +347,7 @@ int nand_calculate_ecc(struct mtd_info *mtd, const unsigned char *buf,
rp17 = (par ^ rp16) & 0xff;
/*
- * Finally calculate the ecc bits.
+ * Finally calculate the ECC bits.
* Again here it might seem that there are performance optimisations
* possible, but benchmarks showed that on the system this is developed
* the code below is the fastest
@@ -412,27 +410,43 @@ int nand_calculate_ecc(struct mtd_info *mtd, const unsigned char *buf,
(invparity[par & 0x55] << 2) |
(invparity[rp17] << 1) |
(invparity[rp16] << 0);
+}
+EXPORT_SYMBOL(__nand_calculate_ecc);
+
+/**
+ * nand_calculate_ecc - [NAND Interface] Calculate 3-byte ECC for 256/512-byte
+ * block
+ * @mtd: MTD block structure
+ * @buf: input buffer with raw data
+ * @code: output buffer with ECC
+ */
+int nand_calculate_ecc(struct mtd_info *mtd, const unsigned char *buf,
+ unsigned char *code)
+{
+ __nand_calculate_ecc(buf,
+ ((struct nand_chip *)mtd->priv)->ecc.size, code);
+
return 0;
}
EXPORT_SYMBOL(nand_calculate_ecc);
/**
- * nand_correct_data - [NAND Interface] Detect and correct bit error(s)
- * @mtd: MTD block structure
+ * __nand_correct_data - [NAND Interface] Detect and correct bit error(s)
* @buf: raw data read from the chip
* @read_ecc: ECC from the chip
* @calc_ecc: the ECC calculated from raw data
+ * @eccsize: data bytes per ECC step (256 or 512)
*
- * Detect and correct a 1 bit error for 256/512 byte block
+ * Detect and correct a 1 bit error for eccsize byte block
*/
-int nand_correct_data(struct mtd_info *mtd, unsigned char *buf,
- unsigned char *read_ecc, unsigned char *calc_ecc)
+int __nand_correct_data(unsigned char *buf,
+ unsigned char *read_ecc, unsigned char *calc_ecc,
+ unsigned int eccsize)
{
- unsigned char b0, b1, b2;
- unsigned char byte_addr, bit_addr;
+ unsigned char b0, b1, b2, bit_addr;
+ unsigned int byte_addr;
/* 256 or 512 bytes/ecc */
- const uint32_t eccsize_mult =
- (((struct nand_chip *)mtd->priv)->ecc.size) >> 8;
+ const uint32_t eccsize_mult = eccsize >> 8;
/*
* b0 to b2 indicate which bit is faulty (if any)
@@ -475,7 +489,7 @@ int nand_correct_data(struct mtd_info *mtd, unsigned char *buf,
*
* The b2 shift is there to get rid of the lowest two bits.
* We could also do addressbits[b2] >> 1 but for the
- * performace it does not make any difference
+ * performance it does not make any difference
*/
if (eccsize_mult == 1)
byte_addr = (addressbits[b1] << 4) + addressbits[b0];
@@ -490,11 +504,28 @@ int nand_correct_data(struct mtd_info *mtd, unsigned char *buf,
}
/* count nr of bits; use table lookup, faster than calculating it */
if ((bitsperbyte[b0] + bitsperbyte[b1] + bitsperbyte[b2]) == 1)
- return 1; /* error in ecc data; no action needed */
+ return 1; /* error in ECC data; no action needed */
- printk(KERN_ERR "uncorrectable error : ");
+ pr_err("%s: uncorrectable ECC error\n", __func__);
return -1;
}
+EXPORT_SYMBOL(__nand_correct_data);
+
+/**
+ * nand_correct_data - [NAND Interface] Detect and correct bit error(s)
+ * @mtd: MTD block structure
+ * @buf: raw data read from the chip
+ * @read_ecc: ECC from the chip
+ * @calc_ecc: the ECC calculated from raw data
+ *
+ * Detect and correct a 1 bit error for 256/512 byte block
+ */
+int nand_correct_data(struct mtd_info *mtd, unsigned char *buf,
+ unsigned char *read_ecc, unsigned char *calc_ecc)
+{
+ return __nand_correct_data(buf, read_ecc, calc_ecc,
+ ((struct nand_chip *)mtd->priv)->ecc.size);
+}
EXPORT_SYMBOL(nand_correct_data);
MODULE_LICENSE("GPL");