yaffs 制作4bit ecctype

海思开发板里自带制作1bit ecc的例程.但是我改为制作4bitecc的类型以后出现了问题:

console输出如下:
   pushd /opt/Hi3531_SDK_V2.0.A.0/osdrv/pub/bin/pc;./mkyaffs2image /opt/Hi3531_SDK_V2.0.A.0/osdrv/pub/rootfs_glibc/ /opt/Hi3531_SDK_V2.0.A.0/osdrv/pub/image_glibc/rootfs_2k_4bit.yaffs2 1 2;popd
/opt/Hi3531_SDK_V2.0.A.0/osdrv/pub/bin/pc /opt/Hi3531_SDK_V2.0.A.0/osdrv
mkyaffs2image: image building tool for YAFFS2, last update Sep 23 2015 13:35:45.
Version: Linux-2.6.35-Google Nand Controller V301
not support this parameter.
mkyaffs2image Version: Linux-2.6.35-Google Nand Controller V301
Input parameter: pagetype: 1(2K), ecctype: 2(4Bytes)

有制作成功的命令或者方法,探讨.