Hello everyone, after some time of research, I have preliminarily ported the A5E-related BSP code to OpenWRT. Here is the GitHub repository.
Due to some lack of understanding of AW u-boot, this project currently only generates middleware (boot.fex + rootfs.fex) for TINA SDK packaging.
To package it into a usable firmware, the TINA SDK is still required.
In the meantime, I have organized some of the existing firmware available online (including above OpenWRT)