From c0cbfd0e81d879a950ba6f0df3f75ea30c5ab16e Mon Sep 17 00:00:00 2001 From: Atsushi Nemoto Date: Sat, 5 Sep 2009 01:20:45 +0900 Subject: mtd: nand: txx9ndfmc: transfer 512 byte at a time if possible Using __nand_correct_data() helper function, this driver can read 512 byte (with 6 byte ECC) at a time. This results minor performance improvement. Signed-off-by: Atsushi Nemoto Signed-off-by: David Woodhouse --- drivers/mtd/nand/txx9ndfmc.c | 52 +++++++++++++++++++++++++++++++++++++++----- 1 file changed, 47 insertions(+), 5 deletions(-) (limited to 'drivers/mtd') diff --git a/drivers/mtd/nand/txx9ndfmc.c b/drivers/mtd/nand/txx9ndfmc.c index 488088eff2ca..73af8324d0d0 100644 --- a/drivers/mtd/nand/txx9ndfmc.c +++ b/drivers/mtd/nand/txx9ndfmc.c @@ -189,18 +189,43 @@ static int txx9ndfmc_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat, uint8_t *ecc_code) { struct platform_device *dev = mtd_to_platdev(mtd); + struct nand_chip *chip = mtd->priv; + int eccbytes; u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR); mcr &= ~TXX9_NDFMCR_ECC_ALL; txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR); txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_READ, TXX9_NDFMCR); - ecc_code[1] = txx9ndfmc_read(dev, TXX9_NDFDTR); - ecc_code[0] = txx9ndfmc_read(dev, TXX9_NDFDTR); - ecc_code[2] = txx9ndfmc_read(dev, TXX9_NDFDTR); + for (eccbytes = chip->ecc.bytes; eccbytes > 0; eccbytes -= 3) { + ecc_code[1] = txx9ndfmc_read(dev, TXX9_NDFDTR); + ecc_code[0] = txx9ndfmc_read(dev, TXX9_NDFDTR); + ecc_code[2] = txx9ndfmc_read(dev, TXX9_NDFDTR); + ecc_code += 3; + } txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR); return 0; } +static int txx9ndfmc_correct_data(struct mtd_info *mtd, unsigned char *buf, + unsigned char *read_ecc, unsigned char *calc_ecc) +{ + struct nand_chip *chip = mtd->priv; + int eccsize; + int corrected = 0; + int stat; + + for (eccsize = chip->ecc.size; eccsize > 0; eccsize -= 256) { + stat = __nand_correct_data(buf, read_ecc, calc_ecc, 256); + if (stat < 0) + return stat; + corrected += stat; + buf += 256; + read_ecc += 3; + calc_ecc += 3; + } + return corrected; +} + static void txx9ndfmc_enable_hwecc(struct mtd_info *mtd, int mode) { struct platform_device *dev = mtd_to_platdev(mtd); @@ -244,6 +269,22 @@ static void txx9ndfmc_initialize(struct platform_device *dev) #define TXX9NDFMC_NS_TO_CYC(gbusclk, ns) \ DIV_ROUND_UP((ns) * DIV_ROUND_UP(gbusclk, 1000), 1000000) +static int txx9ndfmc_nand_scan(struct mtd_info *mtd) +{ + struct nand_chip *chip = mtd->priv; + int ret; + + ret = nand_scan_ident(mtd, 1); + if (!ret) { + if (mtd->writesize >= 512) { + chip->ecc.size = mtd->writesize; + chip->ecc.bytes = 3 * (mtd->writesize / 256); + } + ret = nand_scan_tail(mtd); + } + return ret; +} + static int __init txx9ndfmc_probe(struct platform_device *dev) { struct txx9ndfmc_platform_data *plat = dev->dev.platform_data; @@ -321,9 +362,10 @@ static int __init txx9ndfmc_probe(struct platform_device *dev) chip->cmd_ctrl = txx9ndfmc_cmd_ctrl; chip->dev_ready = txx9ndfmc_dev_ready; chip->ecc.calculate = txx9ndfmc_calculate_ecc; - chip->ecc.correct = nand_correct_data; + chip->ecc.correct = txx9ndfmc_correct_data; chip->ecc.hwctl = txx9ndfmc_enable_hwecc; chip->ecc.mode = NAND_ECC_HW; + /* txx9ndfmc_nand_scan will overwrite ecc.size and ecc.bytes */ chip->ecc.size = 256; chip->ecc.bytes = 3; chip->chip_delay = 100; @@ -349,7 +391,7 @@ static int __init txx9ndfmc_probe(struct platform_device *dev) if (plat->wide_mask & (1 << i)) chip->options |= NAND_BUSWIDTH_16; - if (nand_scan(mtd, 1)) { + if (txx9ndfmc_nand_scan(mtd)) { kfree(txx9_priv->mtdname); kfree(txx9_priv); continue; -- cgit v1.2.3