[intel] Quirk away MSI support on 945G/GM.

The PCI caps register reports MSI support even though it isn't really there.

diff --git a/linux-core/i915_drv.c b/linux-core/i915_drv.c
index 012ca82..e399f37 100644 (file)
--- a/linux-core/i915_drv.c
+++ b/linux-core/i915_drv.c
@@ -628,7 +628,16 @@ static int probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
        int ret;
 
-       (void) pci_enable_msi(pdev);
+       /* On the 945G/GM, the chipset reports the MSI capability on the
+        * integrated graphics even though the support isn't actually there
+        * according to the published specs.  It doesn't appear to function
+        * correctly in testing on 945G.
+        * This may be a side effect of MSI having been made available for PEG
+        * and the registers being closely associated.
+        */
+       if (pdev->device != 0x2772 && pdev->device != 0x27A2)
+               (void )pci_enable_msi(pdev);
+
        ret = drm_get_dev(pdev, ent, &driver);
        if (ret && pdev->msi_enabled)
                pci_disable_msi(pdev);