Intel invented the original 32/64-bit PCI bus in the early 1990s to replace the decade old ISA bus used in PC's. It was immediately popular (in comparison to Micro Channel or EISA), being both faster and more supportive of auto-configuration (i.e. "Plug & Play") than the buses it replaced. By the mid-1990s, most new PC's included PCI slots and ISA slots started their gradual phase-out.
None of the above is surprising, and other systems had already pioneered these features for consumer/home computers years before (e.g. Amiga Zorro, MIT's NuBus). But what did surprise me was that non-PC-compatible systems rapidly adopted PCI as well. The PowerPC 604 based Power Macintosh 9500 brought PCI to the Mac product line in 1995, and Apple quickly deprecated NuBus in favor of PCI. Also, several years later, Elbox introduced the Mediator line of PCI bus boards (e.g. Mediator PCI 1200) to the Amiga 68K based computers. Surely, there were many other systems that also had a compatible PCI bus without an Intel processor.
It makes economic sense that Intel would design PCI to support multiple Intel processors, such as 80486/Pentium/Pentium II/etc. Thereby, they were creating a new bus that would support many processor generations and scale up bus performance as the processors also improved. But I don't know what Intel's economic rationale would be in making PCI a common bus and a good choice for designers of non-Intel CPU systems.
My question is:
- Did Intel intend to make PCI a solution for non-Intel systems too, and actually provide some sort of assistance to system integrators who pursued this? If so, then why?
- What hardware, if any, did system integrators have to engineer themselves to adapt non-Intel (e.g. PowerPC, MC68000, etc.) CPU's to the PCI bus? What I'm getting at here is whether these hardware designers had to make new, custom, bus interface hardware, or did they just use something off-the-shelf that was already CPU agnostic.