编译报错。

72平台，编译报错： NAND page size  not supported, set to default 2048！"
  我明明使用到是emmc   配置的也也是emmc，怎么跑到nand这块去了呢?
# Setup tool and nand page size
SignTool=${0%/*}/SignTool
SIMg2imgTool=mediatek/build/tools/SignTool/simg2img
Yaffs2Covert=mediatek/build/tools/SignTool/yimg2img
if [ "$5" = "2K" ] ; then
    NAND_PAGE_SIZE=2048
elif [ "$5" = "4K" ] ; then
    NAND_PAGE_SIZE=4096
elif [ "$5" = "1K" ] ; then
    NAND_PAGE_SIZE=1024
else
    echo "[SignTool] NAND page size $5 not supported, set to default 2048！"
    NAND_PAGE_SIZE=2048
fi
求大神解答。