This package allows you to build and flash to eMMC a jtag breakout program to Rockchip SoCs with or without rootfs. It is based on: https://czak.pl/2020/05/10/bare-tinker-jtag.html
Basically all Rockchip SoCs have JTAG or SWD lines multiplexed with sd-card0 and the default alternate function is not JTAG but sd-card, so we need to change that alternate function pins to JTAG or SWD to access On-Chip debugging.
Refer to the folder named after SoC to build and flash correctly.