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Eiichiro Oiwa6b5c76b2006-10-23 15:14:07 +09001/*
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;
Bjorn Helgaas1ab40ec2008-03-04 16:34:57 -070066 dev_printk(KERN_DEBUG, &pdev->dev, "Boot video device\n");
Eiichiro Oiwa6b5c76b2006-10-23 15:14:07 +090067 }
68}
69DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pci_fixup_video);