Hi Roger, On Tue, 19 Apr 2016 13:28:50 +0300 Roger Quadros <rogerq@xxxxxx> wrote: > > @@ -1921,6 +1927,9 @@ static int omap_nand_probe(struct platform_device *pdev) > > nand_chip->ecc.correct = omap_correct_data; > > mtd_set_ooblayout(mtd, &omap_ooblayout_ops); > > oobbytes_per_step = nand_chip->ecc.bytes; > > + > > + if (nand_chip->options & NAND_BUSWIDTH_16) > > + min_oobbytes = 1; > > Shouldn't this have been > if (!(nand_chip->options & NAND_BUSWIDTH_16) > min_oobbytes = 1; > ? Yep. > > > break; > > > > case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: > > @@ -2038,10 +2047,8 @@ static int omap_nand_probe(struct platform_device *pdev) > > } > > > > /* check if NAND device's OOB is enough to store ECC signatures */ > > - min_oobbytes = (oobbytes_per_step * > > - (mtd->writesize / nand_chip->ecc.size)) + > > - (nand_chip->options & NAND_BUSWIDTH_16 ? > > - BADBLOCK_MARKER_LENGTH : 1); > > + min_oobbytes += (oobbytes_per_step * > > + (mtd->writesize / nand_chip->ecc.size)); > > if (mtd->oobsize < min_oobbytes) { > > dev_err(&info->pdev->dev, > > "not enough OOB bytes required = %d, available=%d\n", > > > > After the above changes BCH with HW ECC worked fine but BCH with SW ECC still failed. > I had to fix it up with the below patch. This is mainly because chip->ecc.steps wasn't > yet initialized before calling nand_bch_init(). > > After the below patch it worked fine with bch4 (hw & sw), bch8 (hw & sw) and ham1. > I couldn't yet verify bch16 though. Thanks for the fix, but I'd prefer fixing the bug for all soft BCH users. Could you try this patch? --->8--- diff --git a/drivers/mtd/nand/nand_bch.c b/drivers/mtd/nand/nand_bch.c index ca9b2a4..3ca3d39 100644 --- a/drivers/mtd/nand/nand_bch.c +++ b/drivers/mtd/nand/nand_bch.c @@ -177,6 +177,16 @@ struct nand_bch_control *nand_bch_init(struct mtd_info *mtd) goto fail; } + /* + * ecc->steps and ecc->total might be used by mtd->ooblayout->ecc(), + * which is called by mtd_ooblayout_count_eccbytes(). + * Make sure they are properly initialized before calling + * mtd_ooblayout_count_eccbytes(). + * FIXME: we should probaly rework the sequencing in nand_scan_tail() + * to avoid setting those fields twice. + */ + nand->ecc.steps = eccsteps; + nand->ecc.total = eccsteps * eccbytes; if (mtd_ooblayout_count_eccbytes(mtd) != (eccsteps*eccbytes)) { printk(KERN_WARNING "invalid ecc layout\n"); goto fail;