Parse bootargs and create /etc/fw_env.config

ubootenv.sh

#!/bin/sh
set -e

fw_env_path="/etc/fw_env.config"
bootargs_param="ubootenv"

cmdline=`cat /proc/cmdline`

# for testing
# cmdline="cmdline mem=128M totalmem=192M sensor=imx222 console=ttyAMA0,115200 phyaddru=0 phyaddrd=1 ubootenv=/dev/mtd1,0x00000,0x40000,0x10000 mtdparts=hi_sfc:320K(uboot),192K(ubootenv),6144K(romfs),5120K(romfail),3072K(app),1536K(config)"

for cmdparam in ${cmdline}; do
    case ${cmdparam} in ${bootargs_param}=*)
        set `echo ${cmdparam} | sed "s/${bootargs_param}=//g" | sed "s/,/ /g"`
        ubootenv_params=$*
        params_count=$#
        if [ ${params_count} -lt 4 ]; then
            echo "Error: uboot env parameters '${bootargs_param}=${ubootenv_params}' is incorrect! Must be ${bootargs_param}=<mtd_path>,<device_offset (hex)>,<env_size (hex)>,<sector_size (hex)>,<number_of_sectors>'"
        fi

        mtd_path=$1
        device_offset=$2
        env_size=$3
        sector_size=$4
        number_of_sectors=1
        if [ ${params_count} -eq 5 ]; then number_of_sectors=$5; fi

        # echo mtd_path ${mtd_path}
        # echo device_offset ${device_offset}
        # echo env_size ${env_size}
        # echo sector_size ${sector_size}
        # echo number_of_sectors ${number_of_sectors}

        printf "" > ${fw_env_path} # clear file

        printf "# Configuration file for fw_(printenv/saveenv) utility.\n" >> ${fw_env_path}
        printf "# MTD device name       Device offset       Env. size       Flash sector size      Number of sectors\n" >> ${fw_env_path}
        printf "${mtd_path}             ${device_offset}    ${env_size}      ${sector_size}        ${number_of_sectors}\n" >> ${fw_env_path}
        printf "\n" >> ${fw_env_path}
    esac
done