On Thu, Aug 1, 2013 at 11:59 AM, Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> wrote: > Dear Bjorn Helgaas, > > On Thu, 1 Aug 2013 10:53:07 -0600, Bjorn Helgaas wrote: >> On Thu, Aug 1, 2013 at 7:44 AM, Thomas Petazzoni >> <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> wrote: >> > The Marvell PCIe driver uses an emulated PCI-to-PCI bridge to be able >> > to dynamically set up MBus address decoding windows for PCI I/O and >> > memory regions depending on the PCI devices enumerated by Linux. >> > >> > However, this emulated PCI-to-PCI bridge logic makes the Linux PCI >> > core believe that prefetchable memory regions are supported (because >> > the registers are read/write), while in fact no adress decoding window >> > is ever created for such regions. Since the Marvell MBus address >> > decoding windows do not distinguish memory regions and prefetchable >> > memory regions, this patch takes a simple approach: change the >> > PCI-to-PCI bridge emulation to let the Linux PCI core know that we >> > don't support prefetchable memory regions. >> > >> > To achieve this, we simply make the prefetchable memory base a >> > read-only register that always returns 0. Reading/writing all the >> > other prefetchable memory related registers has no effect. >> > >> > This problem was originally reported by Finn Hoffmann >> > <finn@xxxxxxxxxxxxx>, who couldn't get a RTL8111/8168B PCI NIC working >> > on the NSA310 Kirkwood platform after updating to 3.11-rc. The problem >> > was that the PCI-to-PCI bridge emulation was making the Linux PCI core >> > believe that we support prefetchable memory, so the Linux PCI core was >> > only filling the prefetchable memory base and limit registers, which >> > does not lead to a MBus window being created. The below patch has been >> > confirmed by Finn Hoffmann to fix his problem on Kirkwood, and has >> > otherwise been successfully tested on the Armada XP GP platform with a >> > e1000e PCIe NIC and a Marvell SATA PCIe card. >> > >> > Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> >> > Reported-by: Finn Hoffmann <finn@xxxxxxxxxxxxx> >> > Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> >> >> Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> >> >> Please merge along with your other pci-mvebu.c changes. > > I don't think we have other pci-mvebu.c lined up for 3.11. All the MSI > stuff, mvebu-mbus DT stuff and so on is for 3.12. > > So I guess you could take that one through your pci tree. Jason, can > you confirm? Oh, I missed the fact that this was for v3.11. I put it in my for-linus branch. Thanks! 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
