操作步骤：
1、复制opkg到小米路由的/data路径下。
下载地址：http://sangbo.pub/soft/opkg/opkg
2、修改/etc/opkg.conf文件，替换为以下内容：
src/gz attitude_adjustment_base http://openwrt.sangbo.pub/barrier_breaker/14.07/ramips/mt7620a/packages/base src/gz attitude_adjustment_packages http://openwrt.sangbo.pub/barrier_breaker/14.07/ramips/mt7620a/packages/packages/ src/gz attitude_adjustment_luci http://openwrt.sangbo.pub/barrier_breaker/14.07/ramips/mt7620a/packages/luci/ src/gz attitude_adjustment_management http://openwrt.sangbo.pub/barrier_breaker/14.07/ramips/mt7620a/packages/management/ src/gz attitude_adjustment_oldpackages http://openwrt.sangbo.pub/barrier_breaker/14.07/ramips/mt7620a/packages/oldpackages/ src/gz attitude_adjustment_routing http://openwrt.sangbo.pub/barrier_breaker/14.07/ramips/mt7620a/packages/routing/ src/gz openwrt_dist http://openwrt-dist.sourceforge.net/releases/ramips/packages src/gz openwrt_dist_luci http://openwrt-dist.sourceforge.net/releases/luci/packages<br> dest root /data dest ram /tmp lists_dir ext /data/var/opkg-lists option overlay_root /data arch all 100 arch ramips 200 arch ramips_24kec 300
原地址可能是被河蟹了，自己代理了一下进行访问，源地址：https://downloads.openwrt.org/
下载地址：http://sangbo.pub/soft/opkg/opkg.conf
3、添加环境变量。修改/etc/profile文件，修改export PATH为：
export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/data:/data/usr/sbin:/data/usr/bin
再这一行下面新添加一行：
export LD_LIBRARY_PATH=/data/usr/lib
4、重启（reboot）生效，或者设置临时变量：
# export PATH=$PATH:/data:/data/usr/bin:/data/usr/sbin # export LD_LIBRARY_PATH=LD_LIBRARY_PATH:/data/usr/lib
5、更新opkg
# opkg update
PS：如果提示错误，缺少libc*。这里需进行安装，注意保持libc为最新版本。
# cd /data # wget http://openwrt.sangbo.pub/barrier_breaker/14.07/ramips/mt7620a/packages/base/libc_0.9.33.2-1_ramips_24kec.ipk # opkg install libc_*.ipk # rm -rf libc_0.9.33.2-1_ramips_24kec.ipk