blob: fe799b11ac0a7e9ce0b6707fe561902a4b4ad4ab [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Do early PCI probing for bug detection when the main PCI subsystem is
3 * not up yet.
4 */
5#include <linux/init.h>
6#include <linux/kernel.h>
7#include <linux/pci.h>
Andy Curridd44647b2006-06-08 00:43:38 -07008#include <linux/acpi.h>
9
Linus Torvalds1da177e2005-04-16 15:20:36 -070010#include <asm/pci-direct.h>
11#include <asm/acpi.h>
Andi Kleenf9262c12006-03-08 17:57:25 -080012#include <asm/apic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013
Andy Curridd44647b2006-06-08 00:43:38 -070014#ifdef CONFIG_ACPI
15
16static int nvidia_hpet_detected __initdata;
17
18static int __init nvidia_hpet_check(unsigned long phys, unsigned long size)
19{
20 nvidia_hpet_detected = 1;
21 return 0;
22}
23#endif
24
Len Brown4be44fc2005-08-05 00:44:28 -040025static int __init check_bridge(int vendor, int device)
Linus Torvalds1da177e2005-04-16 15:20:36 -070026{
Andi Kleenf9262c12006-03-08 17:57:25 -080027#ifdef CONFIG_ACPI
Andy Curridd44647b2006-06-08 00:43:38 -070028 /* According to Nvidia all timer overrides are bogus unless HPET
29 is enabled. */
Len Brown4be44fc2005-08-05 00:44:28 -040030 if (vendor == PCI_VENDOR_ID_NVIDIA) {
Andy Curridd44647b2006-06-08 00:43:38 -070031 nvidia_hpet_detected = 0;
32 acpi_table_parse(ACPI_HPET, nvidia_hpet_check);
33 if (nvidia_hpet_detected == 0) {
34 acpi_skip_timer_override = 1;
35 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070036 }
Andi Kleenf9262c12006-03-08 17:57:25 -080037#endif
38 if (vendor == PCI_VENDOR_ID_ATI && timer_over_8254 == 1) {
39 timer_over_8254 = 0;
40 printk(KERN_INFO "ATI board detected. Disabling timer routing "
41 "over 8254.\n");
42 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 return 0;
44}
Len Brown4be44fc2005-08-05 00:44:28 -040045
46void __init check_acpi_pci(void)
47{
48 int num, slot, func;
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
50 /* Assume the machine supports type 1. If not it will
Andi Kleen0637a702006-09-26 10:52:41 +020051 always read ffffffff and should not have any side effect.
52 Actually a few buggy systems can machine check. Allow the user
53 to disable it by command line option at least -AK */
54 if (!early_pci_allowed())
55 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
57 /* Poor man's PCI discovery */
Len Brown4be44fc2005-08-05 00:44:28 -040058 for (num = 0; num < 32; num++) {
59 for (slot = 0; slot < 32; slot++) {
60 for (func = 0; func < 8; func++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 u32 class;
62 u32 vendor;
Len Brown4be44fc2005-08-05 00:44:28 -040063 class = read_pci_config(num, slot, func,
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 PCI_CLASS_REVISION);
65 if (class == 0xffffffff)
Len Brown4be44fc2005-08-05 00:44:28 -040066 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
68 if ((class >> 16) != PCI_CLASS_BRIDGE_PCI)
Len Brown4be44fc2005-08-05 00:44:28 -040069 continue;
70
71 vendor = read_pci_config(num, slot, func,
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 PCI_VENDOR_ID);
Len Brown4be44fc2005-08-05 00:44:28 -040073
74 if (check_bridge(vendor & 0xffff, vendor >> 16))
75 return;
76 }
77
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 }
79 }
80}