Hello, Please use the following version of the patch. This version has shorter function names and message, and most importantly, better explanation of problem I encountered. [patch starts below] Some BIOSes hide 'overflow' device (dev #6) for i82875P/PE chipsets. The same happens for i82865P/PE. Add a quirk to enable this device. This allows i82875 EDAC driver to bind to chipset's dev #6 and not dev #0 as the latter is used by AGP driver. On my laptop (i82865P based) ACPI code is disabling this device again in \_SB.PCI0._CRS method (called at least at PNP init time). This can be easily worked around by patching DSDT. Signed-off-by: Michał Mirosław <mirq-linux@xxxxxxxxxxxx> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index a47db02..0ca02c7 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -1787,6 +1787,28 @@ 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 -- 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
