The AmigaOS had a pretty small and specific set of features to allow the system to easily adapt to upgraded CPU's, either shipped in upgraded systems from Commodore, or added to the system using hardware accelerators. These did not rely on special binary versions of Kickstart. The main features were:
- Floating point hardware support via dynamically linked math libraries. A major advantage of accelerated hardware was the FPU supported by or included with 020+ processors. This was used automatically by applications that used the system math libraries.
- Use of
SetPatch at system boot. This command patches the system software, and includes support for loading a CPU specific library from LIBS:, such as
68040.library. Since this happens at early boot, it allows any changes needed by the system to support the specific CPU to happen before applications are loaded.
- Use of the
CPU command. This can be run at boot, or any other time, to detect and exploit CPU specific features, including CACHE control, Burst memory access, and relocating Kickstart ROM to higher speed 32-bit RAM.
These features provide enough flexibility at boot time that it was never necessary to build Kickstart ROM images for specific CPUs. Essentially, Kickstart exists in 3 basic forms for: AGA Amigas, ECS/OCS Amigas, and the A4000T. The reason the A4000T is special is just the addition of a 2nd hardware interface for HDDs (IDE+SCSI).
As far as I know, the best thing to do for a 68030 Amiga with ECS is to include
LIBS:68030.library on your boot disk, run
SetPatch, and run the
CPU command with parameters to enable both DATA and INST caches and the FASTROM option. This should give you the stability you need from the patches and the increased performance.
None of this is to imply that you couldn't create a custom Kickstart for a 68030 based Amiga that included some modules compiled (or optimized) for that CPU in the ROM. It is possible, though not trivial to assemble your own Kickstart image using whatever modules you like. But few, if any, standard Kickstart modules ever warranted this special attention. And custom Kickstarts like this usually just included CPU specific patches for added stability - essentially moving some of the
SetPatch functionality into the ROM.