mtd: nand: omap: add CONFIG_NAND_OMAP_ECCSCHEME for selection of ecc-scheme
This patch adds new CONFIG_NAND_OMAP_ECCSCHEME, replacing other distributed
CONFIG_xx used for selecting NAND ecc-schemes.
This patch aims at solving following issues.
1) Currently ecc-scheme is tied to SoC platform, which prevents user to select
other ecc-schemes also supported in hardware. like;
- most of OMAP3 SoC platforms use only 1-bit Hamming ecc-scheme, inspite
the fact that they can use higher ecc-schemes like 8-bit ecc-schemes with
software based error detection (OMAP_ECC_BCH4_CODE_HW_DETECTION_SW).
- most of AM33xx SoC plaforms use 8-bit BCH ecc-scheme for now, but hardware
supports BCH16 ecc-scheme also.
2) Different platforms use different CONFIG_xx to select ecc-schemes, which
adds confusion for user while migrating platforms.
- *CONFIG_NAND_OMAP_ELM* which enables ELM hardware engine, selects only
8-bit BCH ecc-scheme with h/w based error-correction (OMAP_ECC_BCH8_CODE_HW)
whereas ELM hardware engine supports other ecc-schemes also like; BCH4,
and BCH16 (in future).
- *CONFIG_NAND_OMAP_BCH8* selects 8-bit BCH ecc-scheme with s/w based error
correction (OMAP_ECC_BCH8_CODE_HW_DETECTION_SW).
- *CONFIG_SPL_NAND_SOFTECC* selects 1-bit Hamming ecc-scheme using s/w library
Thus adding new *CONFIG_NAND_OMAP_ECCSCHEME* de-couples ecc-scheme dependency
on SoC platform and NAND driver. And user can select ecc-scheme independently
foreach board.
However, selection some hardware based ecc-schemes (OMAP_ECC_BCHx_CODE_HW) still
depends on presence of ELM hardware engine on SoC. (Refer doc/README.nand)
Signed-off-by: Pekon Gupta <pekon@ti.com>
diff --git a/include/configs/omap3_overo.h b/include/configs/omap3_overo.h
index 4641694..00d7c6c 100644
--- a/include/configs/omap3_overo.h
+++ b/include/configs/omap3_overo.h
@@ -325,6 +325,7 @@
10, 11, 12, 13}
#define CONFIG_SYS_NAND_ECCSIZE 512
#define CONFIG_SYS_NAND_ECCBYTES 3
+#define CONFIG_NAND_OMAP_ECCSCHEME OMAP_ECC_HAM1_CODE_HW
#define CONFIG_SYS_NAND_U_BOOT_START CONFIG_SYS_TEXT_BASE
#define CONFIG_SYS_NAND_U_BOOT_OFFS 0x80000