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authorAlex Williamson <alex.williamson@redhat.com>2015-01-13 19:26:50 +0100
committerBjorn Helgaas <bhelgaas@google.com>2015-01-23 22:44:45 +0100
commitd3d2ab43ddae5f958461ac0a9a2b484a68194df5 (patch)
tree60910830d853171b5511653903c53559b9ba768d /drivers/pci
parentPCI: Add ACS quirk for Emulex NICs (diff)
downloadlinux-d3d2ab43ddae5f958461ac0a9a2b484a68194df5.tar.xz
linux-d3d2ab43ddae5f958461ac0a9a2b484a68194df5.zip
PCI: Add DMA alias quirk for Adaptec 3405
The Adaptec 3405 is actually an Intel 80333 I/O processor where the exposed device at 0e.0 is actually the address translation unit of the I/O processor and a hidden, private device at 01.0 masters the DMA for the device. Create a fixed alias between the exposed and hidden devfn so we can enable the IOMMU. Scenarios like this are potentially likely for any device incorporating this I/O processor, so this little bit of abstraction with the fixed alias table should make future additions trivial. Without this fix, booting a system with the Intel IOMMU enabled and an Adaptec 3405 at 02:0e.0 results in a flood of errors like this: dmar: DRHD: handling fault status reg 3 dmar: DMAR:[DMA Write] Request device [02:01.0] fault addr ffbff000 DMAR:[fault reason 02] Present bit in context entry is clear [bhelgaas: changelog, comment] Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: Adaptec OEM Raid Solutions <aacraid@adaptec.com>
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/quirks.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 3fb378aa7c53..45bd8704c99d 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3563,6 +3563,44 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_JMICRON,
quirk_dma_func1_alias);
/*
+ * Some devices DMA with the wrong devfn, not just the wrong function.
+ * quirk_fixed_dma_alias() uses this table to create fixed aliases, where
+ * the alias is "fixed" and independent of the device devfn.
+ *
+ * For example, the Adaptec 3405 is a PCIe card with an Intel 80333 I/O
+ * processor. To software, this appears as a PCIe-to-PCI/X bridge with a
+ * single device on the secondary bus. In reality, the single exposed
+ * device at 0e.0 is the Address Translation Unit (ATU) of the controller
+ * that provides a bridge to the internal bus of the I/O processor. The
+ * controller supports private devices, which can be hidden from PCI config
+ * space. In the case of the Adaptec 3405, a private device at 01.0
+ * appears to be the DMA engine, which therefore needs to become a DMA
+ * alias for the device.
+ */
+static const struct pci_device_id fixed_dma_alias_tbl[] = {
+ { PCI_DEVICE_SUB(PCI_VENDOR_ID_ADAPTEC2, 0x0285,
+ PCI_VENDOR_ID_ADAPTEC2, 0x02bb), /* Adaptec 3405 */
+ .driver_data = PCI_DEVFN(1, 0) },
+ { 0 }
+};
+
+static void quirk_fixed_dma_alias(struct pci_dev *dev)
+{
+ const struct pci_device_id *id;
+
+ id = pci_match_id(fixed_dma_alias_tbl, dev);
+ if (id) {
+ dev->dma_alias_devfn = id->driver_data;
+ dev->dev_flags |= PCI_DEV_FLAGS_DMA_ALIAS_DEVFN;
+ dev_info(&dev->dev, "Enabling fixed DMA alias to %02x.%d\n",
+ PCI_SLOT(dev->dma_alias_devfn),
+ PCI_FUNC(dev->dma_alias_devfn));
+ }
+}
+
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ADAPTEC2, 0x0285, quirk_fixed_dma_alias);
+
+/*
* A few PCIe-to-PCI bridges fail to expose a PCIe capability, resulting in
* using the wrong DMA alias for the device. Some of these devices can be
* used as either forward or reverse bridges, so we need to test whether the