Sun has been designing workstations and servers for over 25 years. In that time, both the architecture and the associated firmware spanned many different implementations, names, and versioning schemes. This table is a brief overview of the major iterations. For brevity, the table includes only SPARC systems.
Overview of Firmware Releases for SPARC Systems
For reference, note that Oracle has a full line of Sun servers based on Intel and AMD x64 processors. The history on the non-SPARC systems side might be filled in at a later date.
All current products provide Oracle Single System Management utilities which include a package of firmware that includes the BIOS, ILOM Service Processor, installation assistants and various other tools and drivers.
There are a number of other types of firmware associated with Sun products and niche markets that Sun is (or was) involved in: