On Wed, Dec 3, 2014 at 2:15 PM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: > In v3.16 (which does contain 5b28541552ef), when pbus_size_mem() sizes > the 64-bit prefetchable window, it only looks for downstream 64-bit > resources. Since the radeon at 01:00.0 has none, we size the window > to 0 + 0x200000 (the 0x200000 part is pci_hotplug_mem_size, to > accommodate future hot-added devices). > > But that's not big enough to hold the radeon BAR 0 [mem > 0xc0000000-0xcfffffff pref], so BAR 0 remains unassigned, so > pci_enable_device() should fail, and radeon doesn't work. > > I don't know what the best fix is, but I think it's probably too > aggressive to *never* use a 64-bit prefetchable window for downstream > 32-bit prefetchable resources. This configuration from BIOS should > just work without us changing anything (although we probably should > trim the window to start at 0xc0000000, which would still work). pci=realloc should workaround the problem, as it would take control of the bridge mmio BAR, and allocate more range for mmio pref under it. Yinghai -- 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
