1 files changed, 62 insertions, 0 deletions

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index f0b3b7166b46..bbad4a9f264f 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -1778,6 +1778,68 @@ static void __devinit quirk_nvidia_ck804_msi_ht_cap(struct pci_dev *dev)
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_CK804_PCIE,
                         quirk_nvidia_ck804_msi_ht_cap);
 
+/*
+ *  Force enable MSI mapping capability on HT bridges  */
+static inline void ht_enable_msi_mapping(struct pci_dev *dev)
+{
+        int pos, ttl = 48;
+
+        pos = pci_find_ht_capability(dev, HT_CAPTYPE_MSI_MAPPING);
+        while (pos && ttl--) {
+                u8 flags;
+
+                if (pci_read_config_byte(dev, pos + HT_MSI_FLAGS,
+                                         &flags) == 0) {
+                        dev_info(&dev->dev, "Enabling HT MSI Mapping\n");
+
+                        pci_write_config_byte(dev, pos + HT_MSI_FLAGS,
+                                              flags | HT_MSI_FLAGS_ENABLE);
+                }
+                pos = pci_find_next_ht_capability(dev, pos,
+                                                  HT_CAPTYPE_MSI_MAPPING);
+        }
+}
+
+static void __devinit nv_msi_ht_cap_quirk(struct pci_dev *dev)
+{
+        struct pci_dev *host_bridge;
+        int pos, ttl = 48;
+
+        /*
+         * HT MSI mapping should be disabled on devices that are below
+         * a non-Hypertransport host bridge. Locate the host bridge...
+         */
+        host_bridge = pci_get_bus_and_slot(0, PCI_DEVFN(0, 0));
+        if (host_bridge == NULL) {
+                dev_warn(&dev->dev,
+                         "nv_msi_ht_cap_quirk didn't locate host bridge\n");
+                return;
+        }
+
+        pos = pci_find_ht_capability(host_bridge, HT_CAPTYPE_SLAVE);
+        if (pos != 0) {
+                /* Host bridge is to HT */
+                ht_enable_msi_mapping(dev);
+                return;
+        }
+
+        /* Host bridge is not to HT, disable HT MSI mapping on this device */
+        pos = pci_find_ht_capability(dev, HT_CAPTYPE_MSI_MAPPING);
+        while (pos && ttl--) {
+                u8 flags;
+
+                if (pci_read_config_byte(dev, pos + HT_MSI_FLAGS,
+                                         &flags) == 0) {
+                        dev_info(&dev->dev, "Quirk disabling HT MSI mapping");
+                        pci_write_config_byte(dev, pos + HT_MSI_FLAGS,
+                                              flags & ~HT_MSI_FLAGS_ENABLE);
+                }
+                pos = pci_find_next_ht_capability(dev, pos,
+                                                  HT_CAPTYPE_MSI_MAPPING);
+        }
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID, nv_msi_ht_cap_quirk);
+
 static void __devinit quirk_msi_intx_disable_bug(struct pci_dev *dev)
 {
         dev->dev_flags |= PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG;