diff options
Diffstat (limited to 'drivers/mtd/nand/nand_ecc.c')
| -rw-r--r-- | drivers/mtd/nand/nand_ecc.c | 73 |
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"); |
