http://uov5vlsywysdx44mykfwhezqazyubs7zyqdrsl7iaawwrtkkdaig5xqd.onion/articles/KIIProAdventures
In fact, there are many other TV Boxes using a similar SoC. As such, many
people succeeded at running U-Boot and a Linux kernel on some of them. While the KII Pro has an eMMC that contains the vendor firmware, it also
has an SD card slot. The TV Box has 2 boot modes, apparently.