diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index a778c84d04a94d960533cae3063eaab5b663da6c..15a8ab7ea911003e612a80124d1ae303993df146 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2017,6 +2017,28 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_BROADCOM, PCI_DEVICE_ID_NX2_5709S, quirk_brcm_570x_limit_vpd); +/* Originally in EDAC sources for i82875P: + * Intel tells BIOS developers to hide device 6 which + * configures the overflow device access containing + * the DRBs - this is where we expose device 6. + * http://www.x86-secret.com/articles/tweak/pat/patsecrets-2.htm + */ +static void __devinit quirk_unhide_mch_dev6(struct pci_dev *dev) +{ + u8 reg; + + if (pci_read_config_byte(dev, 0xF4, ®) == 0 && !(reg & 0x02)) { + dev_info(&dev->dev, "Enabling MCH 'Overflow' Device\n"); + pci_write_config_byte(dev, 0xF4, reg | 0x02); + } +} + +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82865_HB, + quirk_unhide_mch_dev6); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82875_HB, + quirk_unhide_mch_dev6); + + #ifdef CONFIG_PCI_MSI /* Some chipsets do not support MSI. We cannot easily rely on setting * PCI_BUS_FLAGS_NO_MSI in its bus flags because there are actually