From patchwork Mon Oct 8 05:37:46 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [v2,10/14] ARM: OMAP2+: nand: bch capability check Date: Sun, 07 Oct 2012 19:37:46 -0000 From: Mohammed Afzal X-Patchwork-Id: 189910 Message-Id: <9575950c712e397fa9ddca535d167e6c77e1934d.1349672877.git.afzal@ti.com> To: Tony Lindgren , Artem Bityutskiy Cc: Paul Walmsley , Afzal Mohammed , linux-mtd@lists.infradead.org, Jon Hunter , Ivan Djelic , linux-omap@vger.kernel.org, David Woodhouse , linux-arm-kernel@lists.infradead.org Capability of bch schemes could be discovered using soc revision checks. If soc revision indicates that selected ecc scheme is not supported bail out. Signed-off-by: Afzal Mohammed --- arch/arm/mach-omap2/gpmc-nand.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/arch/arm/mach-omap2/gpmc-nand.c b/arch/arm/mach-omap2/gpmc-nand.c index c1b9b1d..7983d54 100644 --- a/arch/arm/mach-omap2/gpmc-nand.c +++ b/arch/arm/mach-omap2/gpmc-nand.c @@ -90,6 +90,27 @@ static int omap2_nand_gpmc_retime( return 0; } +static bool __init gpmc_hwecc_bch_capable(enum omap_ecc ecc_opt) +{ + /* support only OMAP3 class */ + if (!cpu_is_omap34xx()) { + pr_err("BCH ecc is not supported on this CPU\n"); + return 0; + } + + /* + * For now, assume 4-bit mode is only supported on OMAP3630 ES1.x, x>=1. + * Other chips may be added if confirmed to work. + */ + if ((ecc_opt == OMAP_ECC_BCH4_CODE_HW) && + (!cpu_is_omap3630() || (GET_OMAP_REVISION() == 0))) { + pr_err("BCH 4-bit mode is not supported on this CPU\n"); + return 0; + } + + return 1; +} + int __init gpmc_nand_init(struct omap_nand_platform_data *gpmc_nand_data, struct gpmc_timings *gpmc_t) { @@ -128,6 +149,9 @@ int __init 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)) + return -EINVAL; + err = platform_device_register(&gpmc_nand_device); if (err < 0) { dev_err(dev, "Unable to register NAND device\n");