This is used by SoC platforms which do not have built-in ELM
hardware engine required for BCH ECC correction.
+ CONFIG_SYS_NAND_BUSWIDTH_16BIT
+ Indicates that NAND device has 16-bit wide data-bus. In absence of this
+ config, bus-width of NAND device is assumed to be either 8-bit and later
+ determined by reading ONFI params.
+ Above config is useful when NAND device's bus-width information cannot
+ be determined from on-chip ONFI params, like in following scenarios:
+ - SPL boot does not support reading of ONFI parameters. This is done to
+ keep SPL code foot-print small.
+ - In current U-Boot flow using nand_init(), driver initialization
+ happens in board_nand_init() which is called before any device probe
+ (nand_scan_ident + nand_scan_tail), thus device's ONFI parameters are
+ not available while configuring controller. So a static CONFIG_NAND_xx
+ is needed to know the device's bus-width in advance.
+ Some drivers using above config are:
+ drivers/mtd/nand/mxc_nand.c
+ drivers/mtd/nand/ndfc.c
+ drivers/mtd/nand/omap_gpmc.c
+
Platform specific options
=========================
detection. However ECC calculation on such plaforms would still be
done by GPMC controller.
+ CONFIG_NAND_OMAP_ECCSCHEME
+ On OMAP platforms, this CONFIG specifies NAND ECC scheme.
+ It can take following values:
+ OMAP_ECC_HAM1_CODE_SW
+ 1-bit Hamming code using software lib.
+ (for legacy devices only)
+ OMAP_ECC_HAM1_CODE_HW
+ 1-bit Hamming code using GPMC hardware.
+ (for legacy devices only)
+ OMAP_ECC_BCH4_CODE_HW_DETECTION_SW
+ 4-bit BCH code (unsupported)
+ OMAP_ECC_BCH4_CODE_HW
+ 4-bit BCH code (unsupported)
+ OMAP_ECC_BCH8_CODE_HW_DETECTION_SW
+ 8-bit BCH code with
+ - ecc calculation using GPMC hardware engine,
+ - error detection using software library.
+ - requires CONFIG_BCH to enable software BCH library
+ (For legacy device which do not have ELM h/w engine)
+ OMAP_ECC_BCH8_CODE_HW
+ 8-bit BCH code with
+ - ecc calculation using GPMC hardware engine,
+ - error detection using ELM hardware engine.
NOTE:
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