On Wed, 11 Feb 2009 23:02:52 +0100 Micha__ Miros__aw <mirq-linux@xxxxxxxxxxxx> wrote: > 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: Micha__ Miros__aw <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 Where do we stand with Jesse's earlier comment? On Fri, 9 Jan 2009 13:40:02 -0800 Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> wrote: > > This one already got a NAK until Michal can figure out a way to prevent the > SMM code on his machine from hiding this device periodically. -- 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
