On Wed, Mar 27, 2013 at 9:25 AM, Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> wrote: > On Tue, 2013-03-26 at 12:39 -0600, Bjorn Helgaas wrote: >> But we also know pdev is a PCIe device, and I think a PCIe device on a >> root bus must be a "Root Complex Integrated Endpoint" (PCIe spec sec >> 1.3.2.3). Such a device does not have a link at all, so there's no >> point in fiddling with its link speed. > > This is where our IBM hypervisor makes things murky. It doesn't expose > the PCIe parents (basically somewhat makes PCIe look like PCI except we > still have the PCIe caps on the child devices, just no access to the > parent device). Interesting. I wonder if we'll trip over this anywhere else, e.g., ASPM or other link-related things. I guess we'll just have to see if anything else breaks. > It's garbage but can't be fixed (would break AIX :-) > > However we might be able to populate the bus->max_bus_speed from some > architecture specific quirk and have radeon use that. That sounds like a good solution to me. It seems like it's really an arch-specific deviation from the spec, so it'd be nice to have an arch-specific solution for it. 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
