INTEL_AGPCTRL
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x2200);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x2280);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x2280);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x2280);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x0000);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x0000);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x0000);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x0000);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x0000);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x0000);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x0000);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x0000);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x2200);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x2280);
pci_read_config_dword(agp_bridge->dev, INTEL_AGPCTRL, &temp);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, temp & ~(1 << 7));
pci_read_config_dword(agp_bridge->dev, INTEL_AGPCTRL, &temp);
pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, temp | (1 << 7));