https://wiki.openwrt.org/doc/howto/generic.debrick
变砖后需根据类型进行修复，主要有以下四种：
（1）if only something on the JFFS2 partition is broken, you are still able to → boot into OpenWrt failsafe mode
如果仅仅是JFFS2上部分有问题，可以重启进入failsafe模式。
（2）if the SquashFS partition or the Kernel is broken, you cannot boot into failsafe mode any longer. But you still have a functioning bootloader and so you should follow the same procedures as when you first → installed OpenWrt via bootloader.
如果是SquashFS部分或者内核坏掉，并且进入不了failsafe模式，但是bootloader还能正常工作，你可以通过启动完boot后，进行时串口烧写。
（3）if the bootloader is broken, there are only two options left:
如果bootloader也坏掉了，那就只有两种方法了：
a）access your hardware through the → JTAG Port, this should allow you to write to the flash. Restore the bootloader.
通过JTAG口，来进行恢复bootloader。
b）or desolder the flash chip, connect it to some device, that does give you write access to it and restore the bootloader.
通过短接芯片上的某些管脚，来恢复bootloader。