From d016dc42cedbf6102e100fa9ecb58462edfb14f8 Mon Sep 17 00:00:00 2001 From: pekon gupta Date: Mon, 18 Nov 2013 19:03:00 +0530 Subject: 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 --- doc/README.nand | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'doc') 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 -- cgit v1.2.3