blob: acb55a41260dd0ab9ade073d28732dee0ee822f6 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
|
// SPDX-License-Identifier: GPL-2.0
/*
* Exceptions for specific devices. Usually work-arounds for fatal design flaws.
* Derived from fixup.c of i386 tree.
*/
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/vgaarb.h>
#include <linux/screen_info.h>
#include <asm/uv/uv.h>
/*
* 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 its BIOS copied to 0xC0000 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. Before marking the device
* with IORESOURCE_ROM_SHADOW check if a vga_default_device is already set
* by either arch code or vga-arbitration; if so only apply the fixup to this
* already-determined primary video card.
*/
static void pci_fixup_video(struct pci_dev *pdev)
{
struct pci_dev *bridge;
struct pci_bus *bus;
u16 config;
struct resource *res;
if (is_uv_system())
return;
/* Maybe, this machine supports legacy memory map. */
/* Is VGA routed to us? */
bus = pdev->bus;
while (bus) {
bridge = bus->self;
/*
* From information provided by
* "David Miller" <davem@davemloft.net>
* The bridge control register is valid for PCI header
* type BRIDGE, or CARDBUS. Host to PCI controllers use
* PCI header type NORMAL.
*/
if (bridge && (pci_is_bridge(bridge))) {
pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
&config);
if (!(config & PCI_BRIDGE_CTL_VGA))
return;
}
bus = bus->parent;
}
if (!vga_default_device() || pdev == vga_default_device()) {
pci_read_config_word(pdev, PCI_COMMAND, &config);
if (config & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
res = &pdev->resource[PCI_ROM_RESOURCE];
pci_disable_rom(pdev);
if (res->parent)
release_resource(res);
res->start = 0xC0000;
res->end = res->start + 0x20000 - 1;
res->flags = IORESOURCE_MEM | IORESOURCE_ROM_SHADOW |
IORESOURCE_PCI_FIXED;
dev_info(&pdev->dev, "Video device with shadowed ROM at %pR\n",
res);
}
}
}
DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_ANY_ID, PCI_ANY_ID,
PCI_CLASS_DISPLAY_VGA, 8, pci_fixup_video);
|
