chip->ecc.calculate() is used for calculating and fetching of ECC syndrome by processing the data passed during Read/Write accesses.
All H/W based ECC schemes supported in omap2-nand driver use GPMC controller to calculate ECC syndrome. But each BCHx_ECC scheme implements its own function to process and fetch ECC syndrom from GPMC controller. This patch tries to merges the common code for different BCHx_ECC schemes into single omap_calculate_ecc_bch(), And adds schemes specific post-possessing after fetching ECC-syndrome. This removes redundant code and adds scalability for future ECC-schemes. This patch: - [un-touched] omap_calculate_ecc(): Used for HAM1_ECC - [merged] omap3_calculate_ecc_bch4(): Used for BCH4_HW_DETECTION_SW - [merged] omap3_calculate_ecc_bch8(): Used for BCH8_HW_DETECTION_SW - [merged] omap3_calculate_ecc_bch(): Used for BCH4_HW and BCH8_HW - [new] omap_calculate_ecc_bch(): Now used for all BCHx_ECC Signed-off-by: Pekon Gupta <[email protected]> --- drivers/mtd/nand/omap2.c | 249 ++++++++++++++++++----------------------------- 1 file changed, 95 insertions(+), 154 deletions(-) diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index 5321bdcc..7f7a2ee 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -151,7 +151,9 @@ static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc, 0xac, 0x6b, 0xff, 0x99, 0x7b}; static u_char bch4_vector[] = {0x00, 0x6b, 0x31, 0xdd, 0x41, 0xbc, 0x10}; #endif - +static u8 bch4_polynomial[] = {0x28, 0x13, 0xcc, 0x39, 0x96, 0xac, 0x7f}; +static u8 bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2, + 0x97, 0x79, 0xe5, 0x24, 0xb5}; /* oob info generated runtime depending on ecc algorithm and layout selected */ static struct nand_ecclayout omap_oobinfo; /* Define some generic bad / good block scan pattern which are used @@ -950,9 +952,11 @@ static int omap_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u32 val; val = readl(info->reg.gpmc_ecc_config); - if (((val >> ECC_CONFIG_CS_SHIFT) & ~CS_MASK) != info->gpmc_cs) + if (((val >> 1) & 0x07) != info->gpmc_cs) { + pr_err("%s: invalid ECC configuration for chip-select=%d", + DRIVER_NAME, info->gpmc_cs); return -EINVAL; - + } /* read ecc result */ val = readl(info->reg.gpmc_ecc1_result); *ecc_code++ = val; /* P128e, ..., P1e */ @@ -1141,172 +1145,109 @@ static void omap3_enable_hwecc_bch(struct mtd_info *mtd, int mode) writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control); } -#ifdef CONFIG_MTD_NAND_ECC_BCH /** - * omap3_calculate_ecc_bch4 - Generate 7 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_bch4(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; - 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]); - - /* - * Add constant polynomial to remainder, in order to get an ecc - * sequence of 0xFFs for a buffer filled with 0xFFs; and - * left-justify the resulting polynomial. - */ - *ecc_code++ = 0x28 ^ ((val2 >> 12) & 0xFF); - *ecc_code++ = 0x13 ^ ((val2 >> 4) & 0xFF); - *ecc_code++ = 0xcc ^ (((val2 & 0xF) << 4)|((val1 >> 28) & 0xF)); - *ecc_code++ = 0x39 ^ ((val1 >> 20) & 0xFF); - *ecc_code++ = 0x96 ^ ((val1 >> 12) & 0xFF); - *ecc_code++ = 0xac ^ ((val1 >> 4) & 0xFF); - *ecc_code++ = 0x7f ^ ((val1 & 0xF) << 4); - } - - return 0; -} - -/** - * 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 */ - - -#ifdef CONFIG_MTD_NAND_OMAP_BCH -/** - * omap3_calculate_ecc_bch - Generate bytes of ECC bytes + * omap_calculate_ecc_bch - Generate bytes of ECC bytes * @mtd: MTD device structure * @dat: The pointer to data on which ecc is computed * @ecc_code: The ecc_code buffer * * Support calculating of BCH4/8 ecc vectors for the page */ -static int omap3_calculate_ecc_bch(struct mtd_info *mtd, const u_char *dat, - u_char *ecc_code) +static int omap_calculate_ecc_bch(struct mtd_info *mtd, const u_char *dat, + u_char *ecc_calc) { struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, mtd); - unsigned long nsectors, bch_val1, bch_val2, bch_val3, bch_val4; - int i, eccbchtsel; + struct nand_chip *chip = mtd->priv; + enum omap_ecc ecc_opt = info->ecc_opt; + struct gpmc_nand_regs *gpmc_regs = &info->reg; + u32 eccbytes = chip->ecc.bytes; + u_char *ecc_ptr; + u32 nsectors; + int i, val; - nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1; - /* - * find BCH scheme used - * 0 -> BCH4 - * 1 -> BCH8 - */ - eccbchtsel = ((readl(info->reg.gpmc_ecc_config) >> 12) & 0x3); + val = readl(info->reg.gpmc_ecc_config); + if (((val >> 1) & 0x07) != info->gpmc_cs) { + pr_err("%s: invalid ECC configuration for chip-select=%d", + DRIVER_NAME, info->gpmc_cs); + return -EINVAL; + } + nsectors = ((readl(gpmc_regs->gpmc_ecc_config) >> 4) & 0x7) + 1; for (i = 0; i < nsectors; i++) { - - /* Read hw-computed remainder */ - bch_val1 = readl(info->reg.gpmc_bch_result0[i]); - bch_val2 = readl(info->reg.gpmc_bch_result1[i]); - if (eccbchtsel) { - bch_val3 = readl(info->reg.gpmc_bch_result2[i]); - bch_val4 = readl(info->reg.gpmc_bch_result3[i]); + ecc_ptr = ecc_calc; + switch (ecc_opt) { + case OMAP_ECC_HAMMING_CODE_DEFAULT: + case OMAP_ECC_HAMMING_CODE_HW: + case OMAP_ECC_HAMMING_CODE_HW_ROMCODE: + return -EINVAL; + case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: + case OMAP_ECC_BCH4_CODE_HW: + val = readl(gpmc_regs->gpmc_bch_result1[i]); + *(ecc_ptr++) = ((val >> 12) & 0xFF); + *(ecc_ptr++) = ((val >> 4) & 0xFF); + *(ecc_ptr) = ((val >> 0) << 4) & 0xF0; + val = readl(gpmc_regs->gpmc_bch_result0[i]); + *(ecc_ptr) = ((val >> 28) & 0x0F) | *(ecc_ptr); + ecc_ptr++; + *(ecc_ptr++) = ((val >> 20) & 0xFF); + *(ecc_ptr++) = ((val >> 12) & 0xFF); + *(ecc_ptr++) = ((val >> 4) & 0xFF); + *(ecc_ptr++) = ((val >> 0) << 4) & 0xF0; + break; + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: + case OMAP_ECC_BCH8_CODE_HW: + val = readl(gpmc_regs->gpmc_bch_result3[i]); + *(ecc_ptr++) = ((val >> 0) & 0xFF); + val = readl(gpmc_regs->gpmc_bch_result2[i]); + *(ecc_ptr++) = ((val >> 24) & 0xFF); + *(ecc_ptr++) = ((val >> 16) & 0xFF); + *(ecc_ptr++) = ((val >> 8) & 0xFF); + *(ecc_ptr++) = ((val >> 0) & 0xFF); + val = readl(gpmc_regs->gpmc_bch_result1[i]); + *(ecc_ptr++) = ((val >> 24) & 0xFF); + *(ecc_ptr++) = ((val >> 16) & 0xFF); + *(ecc_ptr++) = ((val >> 8) & 0xFF); + *(ecc_ptr++) = ((val >> 0) & 0xFF); + val = readl(gpmc_regs->gpmc_bch_result0[i]); + *(ecc_ptr++) = ((val >> 24) & 0xFF); + *(ecc_ptr++) = ((val >> 16) & 0xFF); + *(ecc_ptr++) = ((val >> 8) & 0xFF); + *(ecc_ptr++) = ((val >> 0) & 0xFF); + break; + default: + return -EINVAL; } - - if (eccbchtsel) { - /* BCH8 ecc scheme */ - *ecc_code++ = (bch_val4 & 0xFF); - *ecc_code++ = ((bch_val3 >> 24) & 0xFF); - *ecc_code++ = ((bch_val3 >> 16) & 0xFF); - *ecc_code++ = ((bch_val3 >> 8) & 0xFF); - *ecc_code++ = (bch_val3 & 0xFF); - *ecc_code++ = ((bch_val2 >> 24) & 0xFF); - *ecc_code++ = ((bch_val2 >> 16) & 0xFF); - *ecc_code++ = ((bch_val2 >> 8) & 0xFF); - *ecc_code++ = (bch_val2 & 0xFF); - *ecc_code++ = ((bch_val1 >> 24) & 0xFF); - *ecc_code++ = ((bch_val1 >> 16) & 0xFF); - *ecc_code++ = ((bch_val1 >> 8) & 0xFF); - *ecc_code++ = (bch_val1 & 0xFF); - /* - * Setting 14th byte to zero to handle - * erased page & maintain compatibility - * with RBL - */ - *ecc_code++ = 0x0; - } else { - /* BCH4 ecc scheme */ - *ecc_code++ = ((bch_val2 >> 12) & 0xFF); - *ecc_code++ = ((bch_val2 >> 4) & 0xFF); - *ecc_code++ = ((bch_val2 & 0xF) << 4) | - ((bch_val1 >> 28) & 0xF); - *ecc_code++ = ((bch_val1 >> 20) & 0xFF); - *ecc_code++ = ((bch_val1 >> 12) & 0xFF); - *ecc_code++ = ((bch_val1 >> 4) & 0xFF); - *ecc_code++ = ((bch_val1 & 0xF) << 4); - /* - * Setting 8th byte to zero to handle - * erased page - */ - *ecc_code++ = 0x0; + /* ECC scheme specific syndrome customizations */ + switch (ecc_opt) { + case OMAP_ECC_HAMMING_CODE_DEFAULT: + case OMAP_ECC_HAMMING_CODE_HW: + case OMAP_ECC_HAMMING_CODE_HW_ROMCODE: + return -EINVAL; + case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: + for (i = 0; i < eccbytes; i++) + *(ecc_calc + i) = *(ecc_calc + i) ^ + bch4_polynomial[i]; + break; + case OMAP_ECC_BCH4_CODE_HW: + *(ecc_ptr++) = 0x00; + break; + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: + for (i = 0; i < eccbytes; i++) + *(ecc_calc + i) = *(ecc_calc + i) ^ + bch8_polynomial[i]; + break; + case OMAP_ECC_BCH8_CODE_HW: + *(ecc_ptr++) = 0x00; + break; } + /* update pointer to next sector */ + ecc_calc += eccbytes; } - return 0; } +#ifdef CONFIG_MTD_NAND_OMAP_BCH /** * omap_elm_correct_data - corrects page data area in case error reported * @mtd: MTD device structure @@ -1790,7 +1731,7 @@ static int omap_nand_probe(struct platform_device *pdev) info->nand.ecc.strength = 4; info->nand.ecc.hwctl = omap3_enable_hwecc_bch; info->nand.ecc.correct = nand_bch_correct_data; - info->nand.ecc.calculate = omap3_calculate_ecc_bch4; + info->nand.ecc.calculate = omap_calculate_ecc_bch; /* software bch library is used for locating errors */ info->nand.ecc.priv = nand_bch_init(mtd, info->nand.ecc.size, @@ -1813,7 +1754,7 @@ static int omap_nand_probe(struct platform_device *pdev) info->nand.ecc.strength = 4; info->nand.ecc.hwctl = omap3_enable_hwecc_bch; info->nand.ecc.correct = omap_elm_correct_data; - info->nand.ecc.calculate = omap3_calculate_ecc_bch; + info->nand.ecc.calculate = omap_calculate_ecc_bch; info->nand.ecc.read_page = omap_read_page_bch; info->nand.ecc.write_page = omap_write_page_bch; /* ELM H/W engine is used for locating errors */ @@ -1840,7 +1781,7 @@ static int omap_nand_probe(struct platform_device *pdev) info->nand.ecc.strength = 8; info->nand.ecc.hwctl = omap3_enable_hwecc_bch; info->nand.ecc.correct = nand_bch_correct_data; - info->nand.ecc.calculate = omap3_calculate_ecc_bch8; + info->nand.ecc.calculate = omap_calculate_ecc_bch; /* software bch library is used for locating errors */ info->nand.ecc.priv = nand_bch_init(mtd, info->nand.ecc.size, @@ -1863,7 +1804,7 @@ static int omap_nand_probe(struct platform_device *pdev) info->nand.ecc.strength = 8; info->nand.ecc.hwctl = omap3_enable_hwecc_bch; info->nand.ecc.correct = omap_elm_correct_data; - info->nand.ecc.calculate = omap3_calculate_ecc_bch; + info->nand.ecc.calculate = omap_calculate_ecc_bch; info->nand.ecc.read_page = omap_read_page_bch; info->nand.ecc.write_page = omap_write_page_bch; /* ELM H/W engine is used for locating errors */ -- 1.8.1 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
