I changed the approach. Instead of just messing around in assembly, I will do most of it in C and assembly is only for the bootloader. Yes, bootloader. Simplest way to keep this as bare-metal and universal as possible was, in my opinion, to just write a kernel, grub, crosscompile for i868 (in distrobox because the toolchain doesnt run on my distro) and boot via QEMU. I got far enough that it compiles and builds into an ISO, but doesnt actaully even boot, instead bugs out in SeaBIOS. Seems I bit off more than I could chew.