There is an OpenOCD fork (https://github.com/sysprogs/esp8266-openocd) that has ESP8266 support, it needs a little work to compile on Linux though. I believe I still have the modifications if anybody is interested, it compiles, but I'm not sure my modifications are sound.
Freeck wrote:Then why did you not use xt-ocd or gdbstub on Linux? Xt-ocd does not support Altera USB Blaster. I do not know what the status of the latests OpenOCD driver is, but I assume that it does support Altera Usb-blaster.
I would recommend to leave jtag , it is rather instable and it takes 4 IO pins...
Instead consider using this option: viewtopic.php?f=9&t=6932. Although the present Gdbstub-version has some drawbacks: it takes iram, and has a bug (single stepping not working correctly under all circumstances) , I am satisfied with this option so far.