Q: Under what circumstances does the
Macintosh generate a Type 1 cycle? For
machines with a single PCI bus, it seems they are never generated.
A: All of Apple's PCI PowerMac CPUs support hierarchical PCI buses.
Depending on the PCI bus environment, the PPC host to PCI bridge (Bandit chip)
will generate Configuration Type 0 commands to select a device on the PCI
bus where the cycle is being run, and Configuration Type 1 commands to
select devices behind a PCI-to-PCI bridge (Multi-Function PCI cards, for example,
use a PCI-to-PCI bridge).
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