On Fri, Jun 22, 2012 at 10:53 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > On Friday 22 June 2012, Bjorn Helgaas wrote: >> The requirement (if there is one) isn't anything related to PC-ness. >> I just don't understand how things can actually work if two host >> bridges both claim the same bus number. If we do a config read to >> that bus, both bridges should claim it and turn it into config cycles >> on their respective root buses, and we should get two responses. I >> would expect the second response to cause an "unexpected response" >> machine check or similar. > > But each PCI domain has its own config space, so if you do a config > read for one bus, it's always relative to the domain. Oh, I see! I totally missed the fact that each host bridge was in its own domain. If each has its own domain, then the bus number aperture can certainly be [bus 00-ff] and there's no problem. -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
