So, I tried to adapt @Kwiboo and @jernej patches on my 5.6 branch, but this made the kernel fail to boot for no visible reason. Since I were able to boot it without the VPU patches, I'm convinced that it's their readaptation that broke something. The patches applied are here : https://github.com/Miouyouyou/RockMyy64 If someone wants to play with them and determine which one break the boot process.