On Thu, Jun 27, 2013 at 04:39:41PM -0600, Alex Williamson wrote: > v2: > > Revised patch 1/ to match comments from Bjorn. PCIe event collectors > and PCIe-to-PCI bridges now indicate that they do not support ACS. > I've reached out to try to get clarification on this, but I think it's > reasonable to proceed with a conservative approach until then. I also > added PCI-to-PCIe bridges for the sake of being complete. Also added > more comments about the purpose and behavior of pci_acs_enabled(). If > I've overlooked anything else that needs to be addressed, please let > me know. > > Patch 2/ had no comments, it's unchanged. > > Patch 3/ is added. This was sent as an RFC nearly a year ago and > Joerg confirmed for us that these devices do not support p2p on AMD > systems with AMD IOMMU. We can't simply use iommu_present() to test > for an IOMMU because it's setup just after we need this function. > Instead we test for the ACPI IVRS table that describes the IOMMU. It > would probably suffice to skip an actual AMD IOMMU check, but I don't > want it to later come bite us if these ASICs get re-used, maybe with > a different IOMMU, and don't make the same guarantees. > > Joerg, I was also curious back when we investigated this patch if the > same rules hold true for these other southbridge devices: > > 1002:43a0 SB700/SB800/SB900 PCI to PCI bridge (PCIE port 0) > 1002:43a1 SB700/SB800/SB900 PCI to PCI bridge (PCIE port 1) > 1002:43a2 SB900 PCI to PCI bridge (PCIE port 2) > 1002:43a3 SB900 PCI to PCI bridge (PCIE port 3) > > If you remember or have contacts to poke, I'd be happy to follow-up > with another patch to add them. Thanks, > > Alex > > --- > > Alex Williamson (3): > pci: Fix flaw in pci_acs_enabled() > pci: Differentiate ACS controllable from enabled > pci: ACS quirk for AMD southbridge Applied to pci/aw-acs-fixes-v2 for v3.12, thanks! -- 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
