From 7bcd1dca1d587ad29f9825ba4414620440e8c8da Mon Sep 17 00:00:00 2001 From: Pekon Gupta Date: Wed, 26 Feb 2014 15:53:14 +0530 Subject: [PATCH] mtd: nand: omap: ecc.calculate: merge omap3_calculate_ecc_bch8 in omap_calculate_ecc_bch merge omap3_calculate_ecc_bch8() into omap_calculate_ecc_bch() so that common callback can be used for both OMAP_ECC_BCH8_CODE_HW and OMAP_ECC_BCH8_CODE_HW_DETECTION_SW +---------------------+-------------------------------------------------------+ |ecc-scheme | nand_chip->calculate() after this patch | +---------------------+-------------------------------------------------------+ |HAM1_ECC | omap_calculate_ecc() | +---------------------+-------------------------------------------------------+ |BCH4_HW_DETECTION_SW | omap_calculate_ecc_bch() | |BCH4_HW | omap_calculate_ecc_bch() | |BCH8_HW_DETECTION_SW | omap3_calculate_ecc_bch8() -> omap_calculate_ecc_bch()| |BCH8_HW | omap_calculate_ecc_bch() | +---------------------+-------------------------------------------------------+ Tested-by: Stefan Roese Signed-off-by: Pekon Gupta Signed-off-by: Brian Norris --- drivers/mtd/nand/omap2.c | 59 +++++++--------------------------------- 1 file changed, 10 insertions(+), 49 deletions(-) diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index e536267231e2..fa8143624384 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -1122,54 +1122,8 @@ static void omap3_enable_hwecc_bch(struct mtd_info *mtd, int mode) } #endif static u8 bch4_polynomial[] = {0x28, 0x13, 0xcc, 0x39, 0x96, 0xac, 0x7f}; - -#ifdef CONFIG_MTD_NAND_ECC_BCH -/** - * omap3_calculate_ecc_bch8 - Generate 13 bytes of ECC bytes - * @mtd: MTD device structure - * @dat: The pointer to data on which ecc is computed - * @ecc_code: The ecc_code buffer - */ -static int omap3_calculate_ecc_bch8(struct mtd_info *mtd, const u_char *dat, - u_char *ecc_code) -{ - struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, - mtd); - unsigned long nsectors, val1, val2, val3, val4; - int i; - - nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1; - - for (i = 0; i < nsectors; i++) { - - /* Read hw-computed remainder */ - val1 = readl(info->reg.gpmc_bch_result0[i]); - val2 = readl(info->reg.gpmc_bch_result1[i]); - val3 = readl(info->reg.gpmc_bch_result2[i]); - val4 = readl(info->reg.gpmc_bch_result3[i]); - - /* - * Add constant polynomial to remainder, in order to get an ecc - * sequence of 0xFFs for a buffer filled with 0xFFs. - */ - *ecc_code++ = 0xef ^ (val4 & 0xFF); - *ecc_code++ = 0x51 ^ ((val3 >> 24) & 0xFF); - *ecc_code++ = 0x2e ^ ((val3 >> 16) & 0xFF); - *ecc_code++ = 0x09 ^ ((val3 >> 8) & 0xFF); - *ecc_code++ = 0xed ^ (val3 & 0xFF); - *ecc_code++ = 0x93 ^ ((val2 >> 24) & 0xFF); - *ecc_code++ = 0x9a ^ ((val2 >> 16) & 0xFF); - *ecc_code++ = 0xc2 ^ ((val2 >> 8) & 0xFF); - *ecc_code++ = 0x97 ^ (val2 & 0xFF); - *ecc_code++ = 0x79 ^ ((val1 >> 24) & 0xFF); - *ecc_code++ = 0xe5 ^ ((val1 >> 16) & 0xFF); - *ecc_code++ = 0x24 ^ ((val1 >> 8) & 0xFF); - *ecc_code++ = 0xb5 ^ (val1 & 0xFF); - } - - return 0; -} -#endif /* CONFIG_MTD_NAND_ECC_BCH */ +static u8 bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2, + 0x97, 0x79, 0xe5, 0x24, 0xb5}; /** * omap_calculate_ecc_bch - Generate bytes of ECC bytes @@ -1194,6 +1148,7 @@ static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd, for (i = 0; i < nsectors; i++) { ecc_code = ecc_calc; switch (info->ecc_opt) { + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: case OMAP_ECC_BCH8_CODE_HW: bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]); bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]); @@ -1242,6 +1197,12 @@ static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd, /* Set 8th ECC byte as 0x0 for ROM compatibility */ ecc_calc[eccbytes - 1] = 0x0; break; + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: + /* Add constant polynomial to remainder, so that + * ECC of blank pages results in 0x0 on reading back */ + for (i = 0; i < eccbytes; i++) + ecc_calc[i] ^= bch8_polynomial[i]; + break; case OMAP_ECC_BCH8_CODE_HW: /* Set 14th ECC byte as 0x0 for ROM compatibility */ ecc_calc[eccbytes - 1] = 0x0; @@ -1879,7 +1840,7 @@ static int omap_nand_probe(struct platform_device *pdev) nand_chip->ecc.strength = 8; nand_chip->ecc.hwctl = omap3_enable_hwecc_bch; nand_chip->ecc.correct = nand_bch_correct_data; - nand_chip->ecc.calculate = omap3_calculate_ecc_bch8; + nand_chip->ecc.calculate = omap_calculate_ecc_bch; /* define ECC layout */ ecclayout->eccbytes = nand_chip->ecc.bytes * (mtd->writesize / -- 2.39.5