> It means the bus on which legacy I/O ports can be found. It's a fairly > broken concept; each host bridge should really be treated as a > completely separate entity, and if something like a VGA card has legacy > I/O ports that need to be used, they should be looked for on the same > PCI bus as the card itself. Legacy ISA ports should be discovered > through the device tree (or platform devices, or whatever) that > explicitly state which PCI-to-ISA bridge they're under.
Currently, Linux does not allow multiple PCI domains to use overlapping legacy I/O ranges. Yeah it's a pain. > Yes, apparently -- according to a recent thread here, recent versions > of > the PCI spec removed the wording that prohibited a zero BAR (is there > then no way to disable a BAR?). I couldn't find that prohibition even in ancient versions of the PCI specification, for what it's worth. Maybe I'm just blind. > Still, it'd be better to avoid it. Yeah, many drivers go bonkers otherwise. Some devices might misbehave, too. Segher _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
