| Message ID | 1378986619-26765-4-git-send-email-pekon@ti.com |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Sep 12, 2013 at 05:20:18PM +0530, Pekon Gupta wrote: > This patch adds following two flavours of BCH4 ECC scheme in omap2-nand driver > - OMAP_ECC_BCH4_CODE_HW_DETECTION_SW > - uses GPMC H/W engine for calculating ECC. > - uses software library (lib/bch.h & nand_bch.h) for error correction. > > - OMAP_ECC_BCH4_CODE_HW > - uses GPMC H/W engine for calculating ECC. > - uses ELM H/W engine for error correction. > > With this patch omap2-nand driver supports following ECC schemes: > +---------------------------------------+---------------+---------------+ > | ECC scheme |ECC calculation|Error detection| > +---------------------------------------+---------------+---------------+ > |OMAP_ECC_HAMMING_CODE_DEFAULT |S/W |S/W | > |OMAP_ECC_HAMMING_CODE_HW |H/W (GPMC) |S/W | > |OMAP_ECC_HAMMING_CODE_HW_ROMCODE |H/W (GPMC) |S/W | > +---------------------------------------+---------------+---------------+ > |OMAP_ECC_BCH4_CODE_HW_DETECTION_SW |H/W (GPMC) |S/W (lib/bch.h)| > |OMAP_ECC_BCH4_CODE_HW |H/W (GPMC) |H/W (ELM) | > +---------------------------------------+---------------+---------------+ > |OMAP_ECC_BCH8_CODE_HW_DETECTION_SW |H/W (GPMC) |S/W (lib/bch.h)| > |OMAP_ECC_BCH8_CODE_HW |H/W (GPMC) |H/W (ELM) | > +---------------------------------------+---------------+---------------+ > Important: > - Selection of OMAP_ECC_BCHx_CODE_HW_DETECTION_SW requires, > Kconfig: CONFIG_MTD_NAND_ECC_BCH: enables S/W based BCH ECC algorithm. > > - Selection of OMAP_ECC_BCHx_CODE_HW requires, > Kconfig: CONFIG_MTD_NAND_OMAP_BCH: enables ELM H/W module. > > Signed-off-by: Pekon Gupta <pekon@ti.com> > --- > drivers/mtd/nand/Kconfig | 30 ++--------- > drivers/mtd/nand/omap2.c | 136 ++++++++++++++++++++++------------------------- > 2 files changed, 68 insertions(+), 98 deletions(-) > > diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig > index d885298..5836039 100644 > --- a/drivers/mtd/nand/Kconfig > +++ b/drivers/mtd/nand/Kconfig > @@ -96,35 +96,13 @@ config MTD_NAND_OMAP2 > > config MTD_NAND_OMAP_BCH > depends on MTD_NAND && MTD_NAND_OMAP2 && ARCH_OMAP3 > - tristate "Enable support for hardware BCH error correction" > + tristate "Support hardware based BCH error correction" > default n > select BCH > - select BCH_CONST_PARAMS > help > - Support for hardware BCH error correction. > - > -choice > - prompt "BCH error correction capability" > - depends on MTD_NAND_OMAP_BCH > - > -config MTD_NAND_OMAP_BCH8 > - bool "8 bits / 512 bytes (recommended)" > - help > - Support correcting up to 8 bitflips per 512-byte block. > - This will use 13 bytes of spare area per 512 bytes of page data. > - This is the recommended mode, as 4-bit mode does not work > - on some OMAP3 revisions, due to a hardware bug. > - > -config MTD_NAND_OMAP_BCH4 > - bool "4 bits / 512 bytes" > - help > - Support correcting up to 4 bitflips per 512-byte block. > - This will use 7 bytes of spare area per 512 bytes of page data. > - Note that this mode does not work on some OMAP3 revisions, due to a > - hardware bug. Please check your OMAP datasheet before selecting this > - mode. > - > -endchoice > + Some devices have built-in ELM hardware engine, which can be used to > + locate and correct errors when using BCH ECC scheme. This enables the > + driver support for same. > > if MTD_NAND_OMAP_BCH > config BCH_CONST_M > diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c > index 420078f..6f4596c 100644 > --- a/drivers/mtd/nand/omap2.c > +++ b/drivers/mtd/nand/omap2.c > @@ -27,6 +27,7 @@ > > #ifdef CONFIG_MTD_NAND_ECC_BCH > #include <linux/bch.h> > +#include <linux/mtd/nand_bch.h> > #endif > #ifdef CONFIG_MTD_NAND_OMAP_BCH > #include <linux/platform_data/elm.h> > @@ -144,7 +145,6 @@ > #define BCH_ECC_SIZE1 0x20 /* ecc_size1 = 32 */ > > #define BADBLOCK_MARKER_LENGTH 0x2 > -#define OMAP_ECC_BCH8_POLYNOMIAL 0x201b > > #ifdef CONFIG_MTD_NAND_OMAP_BCH > static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc, > @@ -185,10 +185,9 @@ struct omap_nand_info { > OMAP_NAND_IO_WRITE, /* write */ > } iomode; > u_char *buf; > - int buf_len; > + int buf_len; Please do not make unrelated, arbitrary changes to whitespace as part of a patch that solves other problems. > struct gpmc_nand_regs reg; > /* fields specific for BCHx_HW ECC scheme */ > - struct bch_control *bch; > bool is_elm_used; > struct device *elm_dev; > struct device_node *of_node; ... > @@ -1725,16 +1672,17 @@ static int omap_nand_probe(struct platform_device *pdev) > mtd->owner = THIS_MODULE; > mtd->priv = &info->nand; > chip = mtd->priv; > + chip->ecc.priv = NULL; > > info->pdev = pdev; > info->gpmc_cs = pdata->cs; > info->reg = pdata->reg; > - info->bch = NULL; > > info->nand.options = NAND_BUSWIDTH_AUTO; > info->nand.options |= NAND_SKIP_BBTSCAN; > info->of_node = pdata->of_node; > > + Extraneous whitespace. > res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > if (res == NULL) { > err = -EINVAL; > @@ -1924,20 +1872,21 @@ static int omap_nand_probe(struct platform_device *pdev) > info->nand.ecc.bytes = 7; > info->nand.ecc.strength = 4; > info->nand.ecc.hwctl = omap3_enable_hwecc_bch; > - info->nand.ecc.correct = omap3_correct_data_bch; > + info->nand.ecc.correct = nand_bch_correct_data; > info->nand.ecc.calculate = omap3_calculate_ecc_bch4; > /* define custom ECC layout */ > ecclayout->eccbytes = info->nand.ecc.bytes * > - (mtd->writesize / > - info->nand.ecc.size); > + (mtd->writesize / > + info->nand.ecc.size); Again, extraneous changes to the whitespace. > ecclayout->eccpos[0] = info->mtd.oobsize - > - ecclayout->eccbytes; > + ecclayout->eccbytes; Ditto. > ecclayout->oobfree->offset = BADBLOCK_MARKER_LENGTH; > /* software bch library is used for locating errors */ > - info->bch = init_bch(info->nand.ecc.bytes, > - info->nand.ecc.strength, > - OMAP_ECC_BCH8_POLYNOMIAL); > - if (!info->bch) { > + info->nand.ecc.priv = nand_bch_init(mtd, > + info->nand.ecc.size, > + info->nand.ecc.bytes, > + &info->nand.ecc.layout); > + if (!info->nand.ecc.priv) { > pr_err("nand: error: unable to use s/w BCH library\n"); > err = -EINVAL; > goto out_release_mem_region; > @@ -1949,6 +1898,39 @@ static int omap_nand_probe(struct platform_device *pdev) > goto out_release_mem_region; > #endif > break; > + case OMAP_ECC_BCH4_CODE_HW: > +#ifdef CONFIG_MTD_NAND_OMAP_BCH > + pr_info("nand: using OMAP_ECC_BCH4_CODE_HW ECC scheme\n"); > + info->nand.ecc.mode = NAND_ECC_HW; > + info->nand.ecc.size = 512; > + /* 14th bit is kept reserved for ROM-code compatibility */ > + info->nand.ecc.bytes = 7 + 1; > + 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.read_page = omap_read_page_bch; > + info->nand.ecc.write_page = omap_write_page_bch; > + /* This ECC scheme requires ELM H/W block */ > + if (is_elm_present(info, pdata->elm_of_node, BCH4_ECC) < 0) { > + pr_err("nand: error: could not initialize ELM\n"); > + err = -ENODEV; > + goto out_release_mem_region; > + } > + /* define custom ECC layout */ > + ecclayout->eccbytes = info->nand.ecc.bytes * > + (mtd->writesize / > + info->nand.ecc.size); > + ecclayout->eccpos[0] = BADBLOCK_MARKER_LENGTH; > + ecclayout->oobfree->offset = ecclayout->eccpos[0] + > + ecclayout->eccbytes; > + goto custom_ecc_layout; You don't need these 'goto' statements, when they are followed by a 'break' which takes you to the same place. And generally, we reserve goto for use only with error paths, not the common path. I see you did the same thing in patch 2. Please remove them there too. > +#else > + pr_err("nand: error: CONFIG_MTD_NAND_OMAP_BCH not enabled\n"); > + err = -EINVAL; > + goto out_release_mem_region; > +#endif > + break; > case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: > #ifdef CONFIG_MTD_NAND_ECC_BCH > pr_info("nand: using OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n"); > @@ -1957,7 +1939,7 @@ static int omap_nand_probe(struct platform_device *pdev) > info->nand.ecc.bytes = 13; > info->nand.ecc.strength = 8; > info->nand.ecc.hwctl = omap3_enable_hwecc_bch; > - info->nand.ecc.correct = omap3_correct_data_bch; > + info->nand.ecc.correct = nand_bch_correct_data; > info->nand.ecc.calculate = omap3_calculate_ecc_bch8; > /* define custom ECC layout */ > ecclayout->eccbytes = info->nand.ecc.bytes * > @@ -1967,10 +1949,11 @@ static int omap_nand_probe(struct platform_device *pdev) > ecclayout->eccbytes; > ecclayout->oobfree->offset = BADBLOCK_MARKER_LENGTH; > /* software bch library is used for locating errors */ > - info->bch = init_bch(info->nand.ecc.bytes, > - info->nand.ecc.strength, > - OMAP_ECC_BCH8_POLYNOMIAL); > - if (!info->bch) { > + info->nand.ecc.priv = nand_bch_init(mtd, > + info->nand.ecc.size, > + info->nand.ecc.bytes, > + &info->nand.ecc.layout); > + if (!info->nand.ecc.priv) { > pr_err("nand: error: unable to use s/w BCH library\n"); > err = -EINVAL; > goto out_release_mem_region; > @@ -2062,7 +2045,12 @@ out_release_mem_region: > release_mem_region(info->phys_base, info->mem_size); > > out_free_info: > - omap3_free_bch(&info->mtd); Didn't you just add this line in the previous patch? Your patch series is confusing me... > +#ifdef CONFIG_MTD_NAND_ECC_BCH > + if (info->nand.ecc.priv) { > + nand_bch_free(info->nand.ecc.priv); > + info->nand.ecc.priv = NULL; > + } > +#endif I don't think you need this #ifdef, do you? nand_bch_free is stubbed out for the !CONFIG_MTD_NAND_ECC_BCH case. > kfree(info); > > return err; > @@ -2073,8 +2061,12 @@ static int omap_nand_remove(struct platform_device *pdev) > struct mtd_info *mtd = platform_get_drvdata(pdev); > struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, > mtd); > - omap3_free_bch(&info->mtd); > - > +#ifdef CONFIG_MTD_NAND_ECC_BCH > + if (info->nand.ecc.priv) { > + nand_bch_free(info->nand.ecc.priv); > + info->nand.ecc.priv = NULL; > + } > +#endif Ditto. > if (info->dma) > dma_release_channel(info->dma); > Brian
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig index d885298..5836039 100644 --- a/drivers/mtd/nand/Kconfig +++ b/drivers/mtd/nand/Kconfig @@ -96,35 +96,13 @@ config MTD_NAND_OMAP2 config MTD_NAND_OMAP_BCH depends on MTD_NAND && MTD_NAND_OMAP2 && ARCH_OMAP3 - tristate "Enable support for hardware BCH error correction" + tristate "Support hardware based BCH error correction" default n select BCH - select BCH_CONST_PARAMS help - Support for hardware BCH error correction. - -choice - prompt "BCH error correction capability" - depends on MTD_NAND_OMAP_BCH - -config MTD_NAND_OMAP_BCH8 - bool "8 bits / 512 bytes (recommended)" - help - Support correcting up to 8 bitflips per 512-byte block. - This will use 13 bytes of spare area per 512 bytes of page data. - This is the recommended mode, as 4-bit mode does not work - on some OMAP3 revisions, due to a hardware bug. - -config MTD_NAND_OMAP_BCH4 - bool "4 bits / 512 bytes" - help - Support correcting up to 4 bitflips per 512-byte block. - This will use 7 bytes of spare area per 512 bytes of page data. - Note that this mode does not work on some OMAP3 revisions, due to a - hardware bug. Please check your OMAP datasheet before selecting this - mode. - -endchoice + Some devices have built-in ELM hardware engine, which can be used to + locate and correct errors when using BCH ECC scheme. This enables the + driver support for same. if MTD_NAND_OMAP_BCH config BCH_CONST_M diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index 420078f..6f4596c 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -27,6 +27,7 @@ #ifdef CONFIG_MTD_NAND_ECC_BCH #include <linux/bch.h> +#include <linux/mtd/nand_bch.h> #endif #ifdef CONFIG_MTD_NAND_OMAP_BCH #include <linux/platform_data/elm.h> @@ -144,7 +145,6 @@ #define BCH_ECC_SIZE1 0x20 /* ecc_size1 = 32 */ #define BADBLOCK_MARKER_LENGTH 0x2 -#define OMAP_ECC_BCH8_POLYNOMIAL 0x201b #ifdef CONFIG_MTD_NAND_OMAP_BCH static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc, @@ -185,10 +185,9 @@ struct omap_nand_info { OMAP_NAND_IO_WRITE, /* write */ } iomode; u_char *buf; - int buf_len; + int buf_len; struct gpmc_nand_regs reg; /* fields specific for BCHx_HW ECC scheme */ - struct bch_control *bch; bool is_elm_used; struct device *elm_dev; struct device_node *of_node; @@ -1227,58 +1226,6 @@ static int omap3_calculate_ecc_bch8(struct mtd_info *mtd, const u_char *dat, return 0; } -/** - * omap3_correct_data_bch - 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 omap3_correct_data_bch(struct mtd_info *mtd, u_char *data, - u_char *read_ecc, u_char *calc_ecc) -{ - int i, count; - /* cannot correct more than 8 errors */ - unsigned int errloc[8]; - struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, - mtd); - - count = decode_bch(info->bch, NULL, 512, read_ecc, calc_ecc, NULL, - errloc); - if (count > 0) { - /* correct errors */ - for (i = 0; i < count; i++) { - /* correct data only, not ecc bytes */ - if (errloc[i] < 8*512) - data[errloc[i]/8] ^= 1 << (errloc[i] & 7); - pr_debug("corrected bitflip %u\n", errloc[i]); - } - } else if (count < 0) { - pr_err("ecc unrecoverable error\n"); - } - return count; -} - -/** - * omap3_free_bch - Release BCH ecc resources - * @mtd: MTD device structure - */ -static void omap3_free_bch(struct mtd_info *mtd) -{ - struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, - mtd); - if (info->bch) { - free_bch(info->bch); - info->bch = NULL; - } -} - -#else - -static void omap3_free_bch(struct mtd_info *mtd) -{ -} - #endif /* CONFIG_MTD_NAND_ECC_BCH */ @@ -1725,16 +1672,17 @@ static int omap_nand_probe(struct platform_device *pdev) mtd->owner = THIS_MODULE; mtd->priv = &info->nand; chip = mtd->priv; + chip->ecc.priv = NULL; info->pdev = pdev; info->gpmc_cs = pdata->cs; info->reg = pdata->reg; - info->bch = NULL; info->nand.options = NAND_BUSWIDTH_AUTO; info->nand.options |= NAND_SKIP_BBTSCAN; info->of_node = pdata->of_node; + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (res == NULL) { err = -EINVAL; @@ -1924,20 +1872,21 @@ static int omap_nand_probe(struct platform_device *pdev) info->nand.ecc.bytes = 7; info->nand.ecc.strength = 4; info->nand.ecc.hwctl = omap3_enable_hwecc_bch; - info->nand.ecc.correct = omap3_correct_data_bch; + info->nand.ecc.correct = nand_bch_correct_data; info->nand.ecc.calculate = omap3_calculate_ecc_bch4; /* define custom ECC layout */ ecclayout->eccbytes = info->nand.ecc.bytes * - (mtd->writesize / - info->nand.ecc.size); + (mtd->writesize / + info->nand.ecc.size); ecclayout->eccpos[0] = info->mtd.oobsize - - ecclayout->eccbytes; + ecclayout->eccbytes; ecclayout->oobfree->offset = BADBLOCK_MARKER_LENGTH; /* software bch library is used for locating errors */ - info->bch = init_bch(info->nand.ecc.bytes, - info->nand.ecc.strength, - OMAP_ECC_BCH8_POLYNOMIAL); - if (!info->bch) { + info->nand.ecc.priv = nand_bch_init(mtd, + info->nand.ecc.size, + info->nand.ecc.bytes, + &info->nand.ecc.layout); + if (!info->nand.ecc.priv) { pr_err("nand: error: unable to use s/w BCH library\n"); err = -EINVAL; goto out_release_mem_region; @@ -1949,6 +1898,39 @@ static int omap_nand_probe(struct platform_device *pdev) goto out_release_mem_region; #endif break; + case OMAP_ECC_BCH4_CODE_HW: +#ifdef CONFIG_MTD_NAND_OMAP_BCH + pr_info("nand: using OMAP_ECC_BCH4_CODE_HW ECC scheme\n"); + info->nand.ecc.mode = NAND_ECC_HW; + info->nand.ecc.size = 512; + /* 14th bit is kept reserved for ROM-code compatibility */ + info->nand.ecc.bytes = 7 + 1; + 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.read_page = omap_read_page_bch; + info->nand.ecc.write_page = omap_write_page_bch; + /* This ECC scheme requires ELM H/W block */ + if (is_elm_present(info, pdata->elm_of_node, BCH4_ECC) < 0) { + pr_err("nand: error: could not initialize ELM\n"); + err = -ENODEV; + goto out_release_mem_region; + } + /* define custom ECC layout */ + ecclayout->eccbytes = info->nand.ecc.bytes * + (mtd->writesize / + info->nand.ecc.size); + ecclayout->eccpos[0] = BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree->offset = ecclayout->eccpos[0] + + ecclayout->eccbytes; + goto custom_ecc_layout; +#else + pr_err("nand: error: CONFIG_MTD_NAND_OMAP_BCH not enabled\n"); + err = -EINVAL; + goto out_release_mem_region; +#endif + break; case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: #ifdef CONFIG_MTD_NAND_ECC_BCH pr_info("nand: using OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n"); @@ -1957,7 +1939,7 @@ static int omap_nand_probe(struct platform_device *pdev) info->nand.ecc.bytes = 13; info->nand.ecc.strength = 8; info->nand.ecc.hwctl = omap3_enable_hwecc_bch; - info->nand.ecc.correct = omap3_correct_data_bch; + info->nand.ecc.correct = nand_bch_correct_data; info->nand.ecc.calculate = omap3_calculate_ecc_bch8; /* define custom ECC layout */ ecclayout->eccbytes = info->nand.ecc.bytes * @@ -1967,10 +1949,11 @@ static int omap_nand_probe(struct platform_device *pdev) ecclayout->eccbytes; ecclayout->oobfree->offset = BADBLOCK_MARKER_LENGTH; /* software bch library is used for locating errors */ - info->bch = init_bch(info->nand.ecc.bytes, - info->nand.ecc.strength, - OMAP_ECC_BCH8_POLYNOMIAL); - if (!info->bch) { + info->nand.ecc.priv = nand_bch_init(mtd, + info->nand.ecc.size, + info->nand.ecc.bytes, + &info->nand.ecc.layout); + if (!info->nand.ecc.priv) { pr_err("nand: error: unable to use s/w BCH library\n"); err = -EINVAL; goto out_release_mem_region; @@ -2062,7 +2045,12 @@ out_release_mem_region: release_mem_region(info->phys_base, info->mem_size); out_free_info: - omap3_free_bch(&info->mtd); +#ifdef CONFIG_MTD_NAND_ECC_BCH + if (info->nand.ecc.priv) { + nand_bch_free(info->nand.ecc.priv); + info->nand.ecc.priv = NULL; + } +#endif kfree(info); return err; @@ -2073,8 +2061,12 @@ static int omap_nand_remove(struct platform_device *pdev) struct mtd_info *mtd = platform_get_drvdata(pdev); struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, mtd); - omap3_free_bch(&info->mtd); - +#ifdef CONFIG_MTD_NAND_ECC_BCH + if (info->nand.ecc.priv) { + nand_bch_free(info->nand.ecc.priv); + info->nand.ecc.priv = NULL; + } +#endif if (info->dma) dma_release_channel(info->dma);
This patch adds following two flavours of BCH4 ECC scheme in omap2-nand driver - OMAP_ECC_BCH4_CODE_HW_DETECTION_SW - uses GPMC H/W engine for calculating ECC. - uses software library (lib/bch.h & nand_bch.h) for error correction. - OMAP_ECC_BCH4_CODE_HW - uses GPMC H/W engine for calculating ECC. - uses ELM H/W engine for error correction. With this patch omap2-nand driver supports following ECC schemes: +---------------------------------------+---------------+---------------+ | ECC scheme |ECC calculation|Error detection| +---------------------------------------+---------------+---------------+ |OMAP_ECC_HAMMING_CODE_DEFAULT |S/W |S/W | |OMAP_ECC_HAMMING_CODE_HW |H/W (GPMC) |S/W | |OMAP_ECC_HAMMING_CODE_HW_ROMCODE |H/W (GPMC) |S/W | +---------------------------------------+---------------+---------------+ |OMAP_ECC_BCH4_CODE_HW_DETECTION_SW |H/W (GPMC) |S/W (lib/bch.h)| |OMAP_ECC_BCH4_CODE_HW |H/W (GPMC) |H/W (ELM) | +---------------------------------------+---------------+---------------+ |OMAP_ECC_BCH8_CODE_HW_DETECTION_SW |H/W (GPMC) |S/W (lib/bch.h)| |OMAP_ECC_BCH8_CODE_HW |H/W (GPMC) |H/W (ELM) | +---------------------------------------+---------------+---------------+ Important: - Selection of OMAP_ECC_BCHx_CODE_HW_DETECTION_SW requires, Kconfig: CONFIG_MTD_NAND_ECC_BCH: enables S/W based BCH ECC algorithm. - Selection of OMAP_ECC_BCHx_CODE_HW requires, Kconfig: CONFIG_MTD_NAND_OMAP_BCH: enables ELM H/W module. Signed-off-by: Pekon Gupta <pekon@ti.com> --- drivers/mtd/nand/Kconfig | 30 ++--------- drivers/mtd/nand/omap2.c | 136 ++++++++++++++++++++++------------------------- 2 files changed, 68 insertions(+), 98 deletions(-)