@Floid:
The official firmware for the Teron is UBoot, which Hyperion wrote. They included RDB support (I'm booting Linux from a boot partition in an RDB right here), and thus all Terons got this ability. It's not like each and every reseller of Teron boards has to write their own firmware...
The dongle code is another matter. That isn't part of UBoot, it's just code placed in the same flashrom by an external program...
I actually believe that someone who buys a Teron to run Linux on it would do himself a favour by looking into using RDB instead of MBR. I've been trying to improve amiga-fdisk so it's easier to create a valid RDB, and Sten Luther (has a Peg, does Linux work) is including the v50 (OS4) bootloader extensions in libparted, the partitioning library used in the upcoming Debian Sarge installer. Now all I have to do is finish my changes to "kernel-package" and submit them. Then we port the AmigaOne "boot-floppies" changes into "debian-installer". From there on, anyone who installs Debian Sarge on a Teron/AmigaOne will have the option to use RDB :-)
(remember that they would have to use the amigaone linux kernel as well ;-) )
Edit:
Ok, they didn't _write_ UBoot. They ported it and added x86 emulator, menu, RDB support and CatWeasel keyboard support. Possibly more.