1.https://web.vip.miui.com/page/info/mio/mio/detail?postId=21522862&app_version=dev.20051
寻找合适的包
2.http://www.miui.com/unlock/index.html
绑定帐号，解锁手机，首次绑定需要等待7天
3.https://web.vip.miui.com/page/info/mio/mio/detail?isTop=0&postId=17936575&fromBoardId=&app_version=dev.10085&ori_version=dev.10085&ori_miui_version=9.12.27&ori_android_version=10&ori_front_version=null&ori_version=dev.10085&ori_miui_version=9.12.27&ori_android_version=10&ori_front_version=null&ori_version=dev.10085&ori_miui_version=20.1.4&ori_android_version=10&ori_front_version=112
线刷教程，下载线刷包后直接解压到桌面，mi flash安装驱动，加载设备，之后选择解压包的路径，刷机即可