From d016dc42cedbf6102e100fa9ecb58462edfb14f8 Mon Sep 17 00:00:00 2001 From: pekon gupta Date: Mon, 18 Nov 2013 19:03:00 +0530 Subject: [PATCH] mtd: nand: omap: enable BCH ECC scheme using ELM for generic platform BCH8_ECC scheme implemented in omap_gpmc.c driver has following favours +-----------------------------------+-----------------+-----------------+ |ECC Scheme | ECC Calculation | Error Detection | +-----------------------------------+-----------------+-----------------+ |OMAP_ECC_BCH8_CODE_HW |GPMC |ELM H/W engine | |OMAP_ECC_BCH8_CODE_HW_DETECTION_SW |GPMC |S/W BCH library | +-----------------------------------+-----------------+-----------------+ Current implementation limits the BCH8_CODE_HW only for AM33xx device family. (using CONFIG_AM33XX). However, other SoC families (like TI81xx) also have ELM hardware module, and can support ECC error detection using ELM. This patch - removes CONFIG_AM33xx Thus this driver can be reused by all devices having ELM h/w engine. - adds omap_select_ecc_scheme() A common function to handle ecc-scheme related configurations. This can be used both during device-probe and via user-space u-boot commads to change ecc-scheme. During device probe ecc-scheme is selected based on CONFIG_NAND_OMAP_ELM or CONFIG_NAND_OMAP_BCH8 - enables CONFIG_BCH S/W library (lib/bch.c) required by OMAP_ECC_BCHx_CODE_HW_DETECTION_SW is enabled by CONFIG_BCH. - enables CONFIG_SYS_NAND_ONFI_DETECTION for auto-detection of ONFI compliant NAND devices - updates following README doc doc/README.nand board/ti/am335x/README doc/README.omap3 Signed-off-by: Pekon Gupta [scottwood@freescale.com: fixed unused variable warning] Signed-off-by: Scott Wood --- arch/arm/include/asm/omap_gpmc.h | 16 ++ doc/README.nand | 11 ++ drivers/mtd/nand/omap_gpmc.c | 324 +++++++++++++++++++------------ 3 files changed, 227 insertions(+), 124 deletions(-) diff --git a/arch/arm/include/asm/omap_gpmc.h b/arch/arm/include/asm/omap_gpmc.h index dd40cb6c16..d4143ecd80 100644 --- a/arch/arm/include/asm/omap_gpmc.h +++ b/arch/arm/include/asm/omap_gpmc.h @@ -68,4 +68,20 @@ } #endif +enum omap_ecc { + /* 1-bit ECC calculation by Software, Error detection by Software */ + OMAP_ECC_HAM1_CODE_SW = 1, /* avoid un-initialized int can be 0x0 */ + /* 1-bit ECC calculation by GPMC, Error detection by Software */ + /* ECC layout compatible to legacy ROMCODE. */ + OMAP_ECC_HAM1_CODE_HW, + /* 4-bit ECC calculation by GPMC, Error detection by Software */ + OMAP_ECC_BCH4_CODE_HW_DETECTION_SW, + /* 4-bit ECC calculation by GPMC, Error detection by ELM */ + OMAP_ECC_BCH4_CODE_HW, + /* 8-bit ECC calculation by GPMC, Error detection by Software */ + OMAP_ECC_BCH8_CODE_HW_DETECTION_SW, + /* 8-bit ECC calculation by GPMC, Error detection by ELM */ + OMAP_ECC_BCH8_CODE_HW, +}; + #endif /* __ASM_OMAP_GPMC_H */ diff --git a/doc/README.nand b/doc/README.nand index ce7ea5e1e9..487548fcb8 100644 --- a/doc/README.nand +++ b/doc/README.nand @@ -180,6 +180,17 @@ Configuration Options: flexibility, so that one day we can eliminate the old mechanism. + CONFIG_SYS_NAND_ONFI_DETECTION + Enables detection of ONFI compliant devices during probe. + And fetching device parameters flashed on device, by parsing + ONFI parameter page. + + CONFIG_BCH + Enables software based BCH ECC algorithm present in lib/bch.c + This is used by SoC platforms which do not have built-in ELM + hardware engine required for BCH ECC correction. + + Platform specific options ========================= CONFIG_NAND_OMAP_GPMC diff --git a/drivers/mtd/nand/omap_gpmc.c b/drivers/mtd/nand/omap_gpmc.c index c8288597a4..e6b289dec8 100644 --- a/drivers/mtd/nand/omap_gpmc.c +++ b/drivers/mtd/nand/omap_gpmc.c @@ -15,15 +15,13 @@ #include #include #include -#ifdef CONFIG_AM33XX #include -#endif + +#define BADBLOCK_MARKER_LENGTH 2 +#define SECTOR_BYTES 512 static uint8_t cs; -static __maybe_unused struct nand_ecclayout hw_nand_oob = - GPMC_NAND_HW_ECC_LAYOUT; -static __maybe_unused struct nand_ecclayout hw_bch8_nand_oob = - GPMC_NAND_HW_BCH8_ECC_LAYOUT; +static __maybe_unused struct nand_ecclayout omap_ecclayout; /* * omap_nand_hwcontrol - Set the address pointers corretly for the @@ -233,6 +231,7 @@ struct nand_bch_priv { uint8_t type; uint8_t nibbles; struct bch_control *control; + enum omap_ecc ecc_scheme; }; /* bch types */ @@ -274,17 +273,15 @@ static void omap_hwecc_init_bch(struct nand_chip *chip, int32_t mode) { uint32_t val; uint32_t dev_width = (chip->options & NAND_BUSWIDTH_16) >> 1; -#ifdef CONFIG_AM33XX uint32_t unused_length = 0; -#endif uint32_t wr_mode = BCH_WRAPMODE_6; struct nand_bch_priv *bch = chip->priv; /* Clear the ecc result registers, select ecc reg as 1 */ writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control); -#ifdef CONFIG_AM33XX - wr_mode = BCH_WRAPMODE_1; + if (bch->ecc_scheme == OMAP_ECC_BCH8_CODE_HW) { + wr_mode = BCH_WRAPMODE_1; switch (bch->nibbles) { case ECC_BCH4_NIBBLES: @@ -320,7 +317,7 @@ static void omap_hwecc_init_bch(struct nand_chip *chip, int32_t mode) val |= (unused_length << 22); break; } -#else + } else { /* * This ecc_size_config setting is for BCH sw library. * @@ -333,7 +330,7 @@ static void omap_hwecc_init_bch(struct nand_chip *chip, int32_t mode) * size1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area) */ val = (32 << 22) | (0 << 12); -#endif + } /* ecc size configuration */ writel(val, &gpmc_cfg->ecc_size_config); @@ -376,9 +373,9 @@ static void __maybe_unused omap_ecc_disable(struct mtd_info *mtd) } /* - * BCH8 support (needs ELM and thus AM33xx-only) + * BCH support using ELM module */ -#ifdef CONFIG_AM33XX +#ifdef CONFIG_NAND_OMAP_ELM /* * omap_read_bch8_result - Read BCH result for BCH8 level * @@ -631,20 +628,20 @@ static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip, } return 0; } -#endif /* CONFIG_AM33XX */ +#endif /* CONFIG_NAND_OMAP_ELM */ /* * OMAP3 BCH8 support (with BCH library) */ -#ifdef CONFIG_NAND_OMAP_BCH8 +#ifdef CONFIG_BCH /* - * omap_calculate_ecc_bch - Read BCH ECC result + * omap_calculate_ecc_bch_sw - Read BCH ECC result * * @mtd: MTD device structure * @dat: The pointer to data on which ecc is computed (unused here) * @ecc: The ECC output buffer */ -static int omap_calculate_ecc_bch(struct mtd_info *mtd, const uint8_t *dat, +static int omap_calculate_ecc_bch_sw(struct mtd_info *mtd, const uint8_t *dat, uint8_t *ecc) { int ret = 0; @@ -689,13 +686,13 @@ static int omap_calculate_ecc_bch(struct mtd_info *mtd, const uint8_t *dat, } /** - * omap_correct_data_bch - Decode received data and correct errors + * omap_correct_data_bch_sw - Decode received data and correct errors * @mtd: MTD device structure * @data: page data * @read_ecc: ecc read from nand flash * @calc_ecc: ecc read from HW ECC registers */ -static int omap_correct_data_bch(struct mtd_info *mtd, u_char *data, +static int omap_correct_data_bch_sw(struct mtd_info *mtd, u_char *data, u_char *read_ecc, u_char *calc_ecc) { int i, count; @@ -752,7 +749,150 @@ static void __maybe_unused omap_free_bch(struct mtd_info *mtd) chip_priv->control = NULL; } } -#endif /* CONFIG_NAND_OMAP_BCH8 */ +#endif /* CONFIG_BCH */ + +/** + * omap_select_ecc_scheme - configures driver for particular ecc-scheme + * @nand: NAND chip device structure + * @ecc_scheme: ecc scheme to configure + * @pagesize: number of main-area bytes per page of NAND device + * @oobsize: number of OOB/spare bytes per page of NAND device + */ +static int omap_select_ecc_scheme(struct nand_chip *nand, + enum omap_ecc ecc_scheme, unsigned int pagesize, unsigned int oobsize) { + struct nand_bch_priv *bch = nand->priv; + struct nand_ecclayout *ecclayout = nand->ecc.layout; + int eccsteps = pagesize / SECTOR_BYTES; + int i; + + switch (ecc_scheme) { + case OMAP_ECC_HAM1_CODE_SW: + debug("nand: selected OMAP_ECC_HAM1_CODE_SW\n"); + /* For this ecc-scheme, ecc.bytes, ecc.layout, ... are + * initialized in nand_scan_tail(), so just set ecc.mode */ + bch_priv.control = NULL; + bch_priv.type = 0; + nand->ecc.mode = NAND_ECC_SOFT; + nand->ecc.layout = NULL; + nand->ecc.size = pagesize; + bch->ecc_scheme = OMAP_ECC_HAM1_CODE_SW; + break; + + case OMAP_ECC_HAM1_CODE_HW: + debug("nand: selected OMAP_ECC_HAM1_CODE_HW\n"); + /* check ecc-scheme requirements before updating ecc info */ + if ((3 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) { + printf("nand: error: insufficient OOB: require=%d\n", ( + (3 * eccsteps) + BADBLOCK_MARKER_LENGTH)); + return -EINVAL; + } + bch_priv.control = NULL; + bch_priv.type = 0; + /* populate ecc specific fields */ + nand->ecc.mode = NAND_ECC_HW; + nand->ecc.strength = 1; + nand->ecc.size = SECTOR_BYTES; + nand->ecc.bytes = 3; + nand->ecc.hwctl = omap_enable_hwecc; + nand->ecc.correct = omap_correct_data; + nand->ecc.calculate = omap_calculate_ecc; + /* define ecc-layout */ + ecclayout->eccbytes = nand->ecc.bytes * eccsteps; + for (i = 0; i < ecclayout->eccbytes; i++) + ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes - + BADBLOCK_MARKER_LENGTH; + bch->ecc_scheme = OMAP_ECC_HAM1_CODE_HW; + break; + + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: +#ifdef CONFIG_BCH + debug("nand: selected OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n"); + /* check ecc-scheme requirements before updating ecc info */ + if ((13 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) { + printf("nand: error: insufficient OOB: require=%d\n", ( + (13 * eccsteps) + BADBLOCK_MARKER_LENGTH)); + return -EINVAL; + } + /* check if BCH S/W library can be used for error detection */ + bch_priv.control = init_bch(13, 8, 0x201b); + if (!bch_priv.control) { + printf("nand: error: could not init_bch()\n"); + return -ENODEV; + } + bch_priv.type = ECC_BCH8; + /* populate ecc specific fields */ + nand->ecc.mode = NAND_ECC_HW; + nand->ecc.strength = 8; + nand->ecc.size = SECTOR_BYTES; + nand->ecc.bytes = 13; + nand->ecc.hwctl = omap_enable_ecc_bch; + nand->ecc.correct = omap_correct_data_bch_sw; + nand->ecc.calculate = omap_calculate_ecc_bch_sw; + /* define ecc-layout */ + ecclayout->eccbytes = nand->ecc.bytes * eccsteps; + ecclayout->eccpos[0] = BADBLOCK_MARKER_LENGTH; + for (i = 1; i < ecclayout->eccbytes; i++) { + if (i % nand->ecc.bytes) + ecclayout->eccpos[i] = + ecclayout->eccpos[i - 1] + 1; + else + ecclayout->eccpos[i] = + ecclayout->eccpos[i - 1] + 2; + } + ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes - + BADBLOCK_MARKER_LENGTH; + omap_hwecc_init_bch(nand, NAND_ECC_READ); + bch->ecc_scheme = OMAP_ECC_BCH8_CODE_HW_DETECTION_SW; + break; +#else + printf("nand: error: CONFIG_BCH required for ECC\n"); + return -EINVAL; +#endif + + case OMAP_ECC_BCH8_CODE_HW: +#ifdef CONFIG_NAND_OMAP_ELM + debug("nand: selected OMAP_ECC_BCH8_CODE_HW\n"); + /* check ecc-scheme requirements before updating ecc info */ + if ((14 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) { + printf("nand: error: insufficient OOB: require=%d\n", ( + (14 * eccsteps) + BADBLOCK_MARKER_LENGTH)); + return -EINVAL; + } + /* intialize ELM for ECC error detection */ + elm_init(); + bch_priv.type = ECC_BCH8; + /* populate ecc specific fields */ + nand->ecc.mode = NAND_ECC_HW; + nand->ecc.strength = 8; + nand->ecc.size = SECTOR_BYTES; + nand->ecc.bytes = 14; + nand->ecc.hwctl = omap_enable_ecc_bch; + nand->ecc.correct = omap_correct_data_bch; + nand->ecc.calculate = omap_calculate_ecc_bch; + nand->ecc.read_page = omap_read_page_bch; + /* define ecc-layout */ + ecclayout->eccbytes = nand->ecc.bytes * eccsteps; + for (i = 0; i < ecclayout->eccbytes; i++) + ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes - + BADBLOCK_MARKER_LENGTH; + bch->ecc_scheme = OMAP_ECC_BCH8_CODE_HW; + break; +#else + printf("nand: error: CONFIG_NAND_OMAP_ELM required for ECC\n"); + return -EINVAL; +#endif + + default: + debug("nand: error: ecc scheme not enabled or supported\n"); + return -EINVAL; + } + return 0; +} #ifndef CONFIG_SPL_BUILD /* @@ -763,77 +903,45 @@ static void __maybe_unused omap_free_bch(struct mtd_info *mtd) * @eccstrength - the number of bits that could be corrected * (1 - hamming, 4 - BCH4, 8 - BCH8, 16 - BCH16) */ -void omap_nand_switch_ecc(uint32_t hardware, uint32_t eccstrength) +int __maybe_unused omap_nand_switch_ecc(uint32_t hardware, uint32_t eccstrength) { struct nand_chip *nand; struct mtd_info *mtd; + int err = 0; if (nand_curr_device < 0 || nand_curr_device >= CONFIG_SYS_MAX_NAND_DEVICE || !nand_info[nand_curr_device].name) { - printf("Error: Can't switch ecc, no devices available\n"); - return; + printf("nand: error: no NAND devices found\n"); + return -ENODEV; } mtd = &nand_info[nand_curr_device]; nand = mtd->priv; - nand->options |= NAND_OWN_BUFFERS; - - /* Reset ecc interface */ - nand->ecc.mode = NAND_ECC_NONE; - nand->ecc.read_page = NULL; - nand->ecc.write_page = NULL; - nand->ecc.read_oob = NULL; - nand->ecc.write_oob = NULL; - nand->ecc.hwctl = NULL; - nand->ecc.correct = NULL; - nand->ecc.calculate = NULL; - nand->ecc.strength = eccstrength; - /* Setup the ecc configurations again */ if (hardware) { if (eccstrength == 1) { - nand->ecc.mode = NAND_ECC_HW; - nand->ecc.layout = &hw_nand_oob; - nand->ecc.size = 512; - nand->ecc.bytes = 3; - nand->ecc.hwctl = omap_enable_hwecc; - nand->ecc.correct = omap_correct_data; - nand->ecc.calculate = omap_calculate_ecc; - omap_hwecc_init(nand); - printf("1-bit hamming HW ECC selected\n"); + err = omap_select_ecc_scheme(nand, + OMAP_ECC_HAM1_CODE_HW, + mtd->writesize, mtd->oobsize); + } else if (eccstrength == 8) { + err = omap_select_ecc_scheme(nand, + OMAP_ECC_BCH8_CODE_HW, + mtd->writesize, mtd->oobsize); + } else { + printf("nand: error: unsupported ECC scheme\n"); + return -EINVAL; } -#if defined(CONFIG_AM33XX) || defined(CONFIG_NAND_OMAP_BCH8) - else if (eccstrength == 8) { - nand->ecc.mode = NAND_ECC_HW; - nand->ecc.layout = &hw_bch8_nand_oob; - nand->ecc.size = 512; -#ifdef CONFIG_AM33XX - nand->ecc.bytes = 14; - nand->ecc.read_page = omap_read_page_bch; -#else - nand->ecc.bytes = 13; -#endif - nand->ecc.hwctl = omap_enable_ecc_bch; - nand->ecc.correct = omap_correct_data_bch; - nand->ecc.calculate = omap_calculate_ecc_bch; - omap_hwecc_init_bch(nand, NAND_ECC_READ); - printf("8-bit BCH HW ECC selected\n"); - } -#endif } else { - nand->ecc.mode = NAND_ECC_SOFT; - /* Use mtd default settings */ - nand->ecc.layout = NULL; - nand->ecc.size = 0; - printf("SW ECC selected\n"); + err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_SW, + mtd->writesize, mtd->oobsize); } /* Update NAND handling after ECC mode switch */ - nand_scan_tail(mtd); - - nand->options &= ~NAND_OWN_BUFFERS; + if (!err) + err = nand_scan_tail(mtd); + return err; } #endif /* CONFIG_SPL_BUILD */ @@ -856,7 +964,7 @@ int board_nand_init(struct nand_chip *nand) { int32_t gpmc_config = 0; cs = 0; - + int err = 0; /* * xloader/Uboot's gpmc configuration would have configured GPMC for * nand type of memory. The following logic scans and latches on to the @@ -873,7 +981,7 @@ int board_nand_init(struct nand_chip *nand) cs++; } if (cs >= GPMC_MAX_CS) { - printf("NAND: Unable to find NAND settings in " + printf("nand: error: Unable to find NAND settings in " "GPMC Configuration - quitting\n"); return -ENODEV; } @@ -885,64 +993,32 @@ int board_nand_init(struct nand_chip *nand) nand->IO_ADDR_R = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat; nand->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd; - - nand->cmd_ctrl = omap_nand_hwcontrol; - nand->options = NAND_NO_PADDING | NAND_CACHEPRG; + nand->priv = &bch_priv; + nand->cmd_ctrl = omap_nand_hwcontrol; + nand->options |= NAND_NO_PADDING | NAND_CACHEPRG; /* If we are 16 bit dev, our gpmc config tells us that */ if ((readl(&gpmc_cfg->cs[cs].config1) & 0x3000) == 0x1000) nand->options |= NAND_BUSWIDTH_16; nand->chip_delay = 100; + nand->ecc.layout = &omap_ecclayout; -#if defined(CONFIG_AM33XX) || defined(CONFIG_NAND_OMAP_BCH8) -#ifdef CONFIG_AM33XX - /* AM33xx uses the ELM */ - /* required in case of BCH */ - elm_init(); + /* select ECC scheme */ +#if defined(CONFIG_NAND_OMAP_ELM) + err = omap_select_ecc_scheme(nand, OMAP_ECC_BCH8_CODE_HW, + CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE); +#elif defined(CONFIG_NAND_OMAP_BCH8) + err = omap_select_ecc_scheme(nand, OMAP_ECC_BCH8_CODE_HW_DETECTION_SW, + CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE); +#elif !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_NAND_SOFTECC) + err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_SW, + 0, 0); #else - /* - * Whereas other OMAP based SoC do not have the ELM, they use the BCH - * SW library. - */ - bch_priv.control = init_bch(13, 8, 0x201b /* hw polynominal */); - if (!bch_priv.control) { - puts("Could not init_bch()\n"); - return -ENODEV; - } -#endif - /* BCH info that will be correct for SPL or overridden otherwise. */ - nand->priv = &bch_priv; -#endif - - /* Default ECC mode */ -#if defined(CONFIG_AM33XX) || defined(CONFIG_NAND_OMAP_BCH8) - nand->ecc.mode = NAND_ECC_HW; - nand->ecc.layout = &hw_bch8_nand_oob; - nand->ecc.size = CONFIG_SYS_NAND_ECCSIZE; - nand->ecc.bytes = CONFIG_SYS_NAND_ECCBYTES; - nand->ecc.strength = 8; - nand->ecc.hwctl = omap_enable_ecc_bch; - nand->ecc.correct = omap_correct_data_bch; - nand->ecc.calculate = omap_calculate_ecc_bch; -#ifdef CONFIG_AM33XX - nand->ecc.read_page = omap_read_page_bch; -#endif - omap_hwecc_init_bch(nand, NAND_ECC_READ); -#else -#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_NAND_SOFTECC) - nand->ecc.mode = NAND_ECC_SOFT; -#else - nand->ecc.mode = NAND_ECC_HW; - nand->ecc.layout = &hw_nand_oob; - nand->ecc.size = CONFIG_SYS_NAND_ECCSIZE; - nand->ecc.bytes = CONFIG_SYS_NAND_ECCBYTES; - nand->ecc.hwctl = omap_enable_hwecc; - nand->ecc.correct = omap_correct_data; - nand->ecc.calculate = omap_calculate_ecc; - nand->ecc.strength = 1; - omap_hwecc_init(nand); -#endif + err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_HW, + CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE); #endif + if (err) + return err; #ifdef CONFIG_SPL_BUILD if (nand->options & NAND_BUSWIDTH_16)