OpenWRT交叉编译链生成与安装（mipsel-openwrt-linux-gcc）
# 编译环境变量文件
vim ~/.bashrc
# 文件末尾添加环境变量，指向mipsel-openwrt-linux-gcc目录，并保存退出
export PATH=~/MT7628/openwrt-hiwooya/staging_dir/toolchain-mipsel_24kec+dsp_gcc-4.8-linaro_uClibc-0.9.33.2/bin/:$PATH
export STAGING_DIR=/{openwrt_path}/staging_dir
# 使配置立即生效
source ~/.bashrc
如果报警告warning: environment variable 'STAGING_DIR' not defined，就是没有export STAGING_DIR导致的。
Index of /barrier_breaker/14.07/ramips/mt7620a/
OpenWrt-Toolchain-ramips-for-mipsel_24kec+dsp-gcc-4.8-linaro_uClibc-0.9.33.2.tar.bz2就是编译链工具。
# 下载
wget https://archive.openwrt.org/barrier_breaker/14.07/ramips/mt7620a/OpenWrt-Toolchain-ramips-for-mipsel_24kec+dsp-gcc-4.8-linaro_uClibc-0.9.33.2.tar.bz2
# 解压
tar -jxvf OpenWrt-Toolchain-ramips-for-mipsel_24kec+dsp-gcc-4.8-linaro_uClibc-0.9.33.2.tar.bz2
# 下载
wget https://archive.openwrt.org/barrier_breaker/14.07/ramips/mt7620a/OpenWrt-Toolchain-ramips-for-mipsel_24kec+dsp-gcc-4.8-linaro_uClibc-0.9.33.2.tar.bz2
# 解压
tar -jxvf OpenWrt-Toolchain-ramips-for-mipsel_24kec+dsp-gcc-4.8-linaro_uClibc-0.9.33.2.tar.bz2
# 编译环境变量文件
vim ~/.bashrc
# 文件末尾添加环境变量，指向mipsel-openwrt-linux-gcc目录，并保存退出
export PATH=~/MT7628/OpenWrt-Toolchain-ramips-for-mipsel_24kec+dsp-gcc-4.8-linaro_uClibc-0.9.33.2/bin/:$PATH
export STAGING_DIR=/{openwrt_path}/staging_dir
# 使配置立即生效
source ~/.bashrc
