On Mon, Sep 29, 2014 at 4:31 PM, Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> wrote: > On Mon, 2014-09-29 at 15:33 -0600, Bjorn Helgaas wrote: >> > Right and on powerpc and others as well. We need to survey existing >> > resources. We also have a number of platform things that might need >> > to happen before we do the final re-assignment pass. >> >> That's true today. But I don't know whether it *has* to be this way >> forever. On x86, pcibios_resource_survey() throws in E820 information >> (which we know long before we do any PCI enumeration) and some IO-APIC >> resources (it looks like we also know these before PCI enumeration). >> Powerpc has pcibios_reserve_legacy_regions(), but that looks like >> mostly stuff that could be done when we find the host bridge, before >> we enumerate PCI devices below it. > > Oh we can probably change that but it's going to be much more work than > just moving the assignment into pci_scan_root_bus(). Agreed. It's obvious that we can't apply Liviu's patch as-is. > There are also a > number of subtle and not-so-subtle bits of code that rely on side > effects of the current code such as anything that tests for bus->added > or dev->added. Again, nothing we can't sort out eventually but the > transition might be a bit painful. > > We might need to introduce a new flag for platforms converted to the > "new style" generalized resource assignment which we can deprecate once > everybody has moved over. There's definitely a lot of work here if we ever want to make this happen. Bjorn -- 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
