My embedded device is not working after updating firmware. Thus I tried to update firmware using u-boot. I could successfully get u-boot console via serial connection, but updating firmware failed due to the lack of knowledge on firmware update using u-boot.
At last, I not only corrupted linux kernel but also u-boot while modifying the device flash memory (u-boot command supports flash memory modification). Booting device no longer gives u-boot console. It just stops (I can see it through the serial connection).
In this situation, how can I recover(or update) firmware on my device?