1/* 2 * Exceptions for specific devices. Usually work-arounds for fatal design flaws. 3 * Derived from fixup.c of i386 tree. 4 */ 5 6#include <linux/pci.h> 7#include <linux/init.h> 8 9#include <asm/machvec.h> 10 11/* 12 * Fixup to mark boot BIOS video selected by BIOS before it changes 13 * 14 * From information provided by "Jon Smirl" <jonsmirl@gmail.com> 15 * 16 * The standard boot ROM sequence for an x86 machine uses the BIOS 17 * to select an initial video card for boot display. This boot video 18 * card will have it's BIOS copied to C0000 in system RAM. 19 * IORESOURCE_ROM_SHADOW is used to associate the boot video 20 * card with this copy. On laptops this copy has to be used since 21 * the main ROM may be compressed or combined with another image. 22 * See pci_map_rom() for use of this flag. IORESOURCE_ROM_SHADOW 23 * is marked here since the boot video device will be the only enabled 24 * video device at this point. 25 */ 26 27static void __devinit pci_fixup_video(struct pci_dev *pdev) 28{ 29 struct pci_dev *bridge; 30 struct pci_bus *bus; 31 u16 config; 32 33 if ((strcmp(platform_name, "dig") != 0) 34 && (strcmp(platform_name, "hpzx1") != 0)) 35 return; 36 /* Maybe, this machine supports legacy memory map. */ 37 38 if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA) 39 return; 40 41 /* Is VGA routed to us? */ 42 bus = pdev->bus; 43 while (bus) { 44 bridge = bus->self; 45 46 /* 47 * From information provided by 48 * "David Miller" <davem@davemloft.net> 49 * The bridge control register is valid for PCI header 50 * type BRIDGE, or CARDBUS. Host to PCI controllers use 51 * PCI header type NORMAL. 52 */ 53 if (bridge 54 &&((bridge->hdr_type == PCI_HEADER_TYPE_BRIDGE) 55 ||(bridge->hdr_type == PCI_HEADER_TYPE_CARDBUS))) { 56 pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, 57 &config); 58 if (!(config & PCI_BRIDGE_CTL_VGA)) 59 return; 60 } 61 bus = bus->parent; 62 } 63 pci_read_config_word(pdev, PCI_COMMAND, &config); 64 if (config & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) { 65 pdev->resource[PCI_ROM_RESOURCE].flags |= IORESOURCE_ROM_SHADOW; 66 printk(KERN_DEBUG "Boot video device is %s\n", pci_name(pdev)); 67 } 68} 69DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pci_fixup_video); 70