On Wed, May 01, 2013 at 11:17:10AM -0600, Bjorn Helgaas wrote: > Is there any possibility of multi-function devices at bus 0, device 0, 2, or > 3? > > What about bridges -- can any of these be a bridge? > > If either of those could happen, these checks could be too specific. 0:2:0 and 0:3:0 are the only 2 devices behind the bridge 0:0:0. These devices don't implement pcie capability list in legacy config space so no offset above 255 would be triggered. The fixed bar pcie capability located at 0x100 is for pci-shimed device only, not for 0, 2 and 3. But current implementation applies it to 0, 2 and 3 as well. This is what the patch is going to address.
> > Is there a doc that identifies these cases where config mechanism #1 > should be used instead of MMCONFIG? Unfortunately no doc identifies this. But since FW doesn't provide pci shim for device 0, 2 and 3, and these 3 real pci devices have only 256 bytes legacy pci config space so they can only be accessed by type 1. > > Bjorn > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
