On 08/06/2015 08:58 AM, Yinghai Lu wrote:
On Wed, Aug 5, 2015 at 9:50 PM, Guenter Roeck <linux@xxxxxxxxxxxx> wrote:If I understand you correctly, we might need to change the code in pci_read_bridge_io() as follows. From if (!(child->bus_flags & PCI_BUS_FLAGS_SUPPORTS_IO)) return; to something like if (!(child->bus_flags & PCI_BUS_FLAGS_SUPPORTS_IO)) { if (dev->transparent) return; child->bus_flags |= PCI_BUS_FLAGS_SUPPORTS_IO; }Then how about: the root bus really does not support IO PORT resource.
Ok, I admit that I am lost. Earlier it seemed that you were concerned about this case, where no io window is available or a bus doesn't support io, but a non-transparent child does. Now you seem to say that the non-transparent child would not be able to support IO either. For my education, can you list the possible options, and how you suggest to solve them ? I can see the following situations. - root supports IO, but has no io window assigned - root does not support IO and has or has not an IO window assigned - a bridge does not support IO For the transparent case, each of those should result in all children not even trying to assign an IO window, which is what we want, and what my patc set tries to do. How should those cases be handled for non-transparent bridges ? Thanks, Guenter -- 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
