diff options
Diffstat (limited to 'drivers/pci/quirks.c')
-rw-r--r-- | drivers/pci/quirks.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 1d2ccda..371ab88 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -1619,6 +1619,51 @@ static void __devinit fixup_rev1_53c810(struct pci_dev* dev) } DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NCR, PCI_DEVICE_ID_NCR_53C810, fixup_rev1_53c810); +/* + * Fixup to mark boot BIOS video selected by BIOS before it changes + * + * From information provided by "Jon Smirl" <jonsmirl@gmail.com> + * + * The standard boot ROM sequence for an x86 machine uses the BIOS + * to select an initial video card for boot display. This boot video + * card will have it's BIOS copied to C0000 in system RAM. + * IORESOURCE_ROM_SHADOW is used to associate the boot video + * card with this copy. On laptops this copy has to be used since + * the main ROM may be compressed or combined with another image. + * See pci_map_rom() for use of this flag. IORESOURCE_ROM_SHADOW + * is marked here since the boot video device will be the only enabled + * video device at this point. + */ + +static void __devinit fixup_video(struct pci_dev *pdev) +{ + struct pci_dev *bridge; + struct pci_bus *bus; + u16 config; + + if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA) + return; + + /* Is VGA routed to us? */ + bus = pdev->bus; + while (bus) { + bridge = bus->self; + if (bridge) { + pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, + &config); + if (!(config & PCI_BRIDGE_CTL_VGA)) + return; + } + bus = bus->parent; + } + pci_read_config_word(pdev, PCI_COMMAND, &config); + if (config & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) { + pdev->resource[PCI_ROM_RESOURCE].flags |= IORESOURCE_ROM_SHADOW; + printk(KERN_DEBUG "Boot video device is %s\n", pci_name(pdev)); + } +} +DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, fixup_video); + static void pci_do_fixups(struct pci_dev *dev, struct pci_fixup *f, struct pci_fixup *end) { |