Hi Cristoph, >From: Pekon Gupta <Pekon@xxxxxx> >>From: Christoph Fritz [mailto:chf.fritz@xxxxxxxxxxxxxx] >> >>Most dt omap3 boards configure nand-ecc-opt as bch8. Due >>to lack of hardware elm support, bch8 software implementation >>gets set. >> >>Since commit 0611c41934ab35ce84dea "ARM: OMAP2+: gpmc: update >>gpmc_hwecc_bch_capable() for new platforms and ECC schemes", >>nand support stops working. >> >>This patch allows ecc software fallback. > >Pleas add following tag at top of commit message. > >Fixes: commit 0611c41934ab35ce84dea34ab291897ad3cbc7be >ARM: OMAP2+: gpmc: update gpmc_hwecc_bch_capable() for new platforms and ECC schemes > >And please mark it for 3.15 stable if this gets accepted after 3.15-rcx. >Cc: <stable@xxxxxxxxxxxxxxx> # 3.15.x+ > > >>--- >> arch/arm/mach-omap2/gpmc-nand.c | 16 ++++++---------- >> 1 file changed, 6 insertions(+), 10 deletions(-) >> >>diff --git a/arch/arm/mach-omap2/gpmc-nand.c b/arch/arm/mach-omap2/gpmc-nand.c >>index 4349e82..52c4834 100644 >>--- a/arch/arm/mach-omap2/gpmc-nand.c >>+++ b/arch/arm/mach-omap2/gpmc-nand.c >>@@ -43,13 +43,17 @@ static struct platform_device gpmc_nand_device = { >> .resource = gpmc_nand_resource, >> }; >> >>-static bool gpmc_hwecc_bch_capable(enum omap_ecc ecc_opt) >>+static bool gpmc_ecc_bch_capable(enum omap_ecc ecc_opt) > >I don't think this renaming is really required with this fix, so please >drop it and just keep it simple only for OMAP3 fix. > > >> { >> /* platforms which support all ECC schemes */ >> if (soc_is_am33xx() || cpu_is_omap44xx() || >> soc_is_omap54xx() || soc_is_dra7xx()) >> return 1; >> >>+ if ((ecc_opt == OMAP_ECC_BCH4_CODE_HW_DETECTION_SW) || >>+ (ecc_opt == OMAP_ECC_BCH8_CODE_HW_DETECTION_SW)) >>+ return 1; >>+ > >Note: Some very old legacy platforms have initial version of GPMC engine >which only supports Hamming ECC, and not BCH ECC scheme, so lets >filter them out to maintain backward compatibility. > >(1) As per TRM, OMAP2 platform does not support BCH ECC schemes, > So please filter out OMAP2 devices from this check ... > >(2) I don't know the history but below comment says: >"* For now, assume 4-bit mode is only supported on OMAP3630 ES1.x, x>=1" > >if ((ecc_opt == OMAP_ECC_BCH4_CODE_HW_DETECTION_SW) || > (ecc_opt == OMAP_ECC_BCH8_CODE_HW_DETECTION_SW)) { > if (cpu_is_omap24xx()) > return 0; > else if (cpu_is_omap3630() && (GET_OMAP_REVISION() == 0)) > return 0; > else > return 1; >} > > >> /* OMAP3xxx do not have ELM engine, so cannot support ECC schemes >> * which require H/W based ECC error detection */ >> if ((cpu_is_omap34xx() || cpu_is_omap3630()) && >>@@ -57,14 +61,6 @@ static bool gpmc_hwecc_bch_capable(enum omap_ecc ecc_opt) >> (ecc_opt == OMAP_ECC_BCH8_CODE_HW))) >> return 0; >> >>- /* >>- * For now, assume 4-bit mode is only supported on OMAP3630 ES1.x, x>=1 >>- * and AM33xx derivates. Other chips may be added if confirmed to work. >>- */ >>- if ((ecc_opt == OMAP_ECC_BCH4_CODE_HW_DETECTION_SW) && >>- (!cpu_is_omap3630() || (GET_OMAP_REVISION() == 0))) >>- return 0; >>- >Thanks for removing this, I too wasn't confident of this either. > > >> /* legacy platforms support only HAM1 (1-bit Hamming) ECC scheme */ >> if (ecc_opt == OMAP_ECC_HAM1_CODE_HW) >> return 1; >>@@ -140,7 +136,7 @@ int gpmc_nand_init(struct omap_nand_platform_data *gpmc_nand_data, >> >> gpmc_update_nand_reg(&gpmc_nand_data->reg, gpmc_nand_data->cs); >> >>- if (!gpmc_hwecc_bch_capable(gpmc_nand_data->ecc_opt)) { >>+ if (!gpmc_ecc_bch_capable(gpmc_nand_data->ecc_opt)) { > >Please drop this renaming from this patch. > >> dev_err(dev, "Unsupported NAND ECC scheme selected\n"); >> return -EINVAL; >> } >>-- >>1.7.10.4 > >You may send this patch separately apart from the series, so that >this gets accepted in current 3.15-rcx. > >with regards, Pekon Do you plan to re-spin this patch with above comments, and mark it for stable? It would be helpful for all OMAP3 users. with regards, pekon -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
