Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* |
| 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> |
| 8 | #include <asm/pci-direct.h> |
| 9 | #include <asm/acpi.h> |
| 10 | |
| 11 | static int __init check_bridge(int vendor, int device) |
| 12 | { |
| 13 | /* According to Nvidia all timer overrides are bogus. Just ignore |
| 14 | them all. */ |
| 15 | if (vendor == PCI_VENDOR_ID_NVIDIA) { |
| 16 | acpi_skip_timer_override = 1; |
| 17 | } |
| 18 | return 0; |
| 19 | } |
| 20 | |
| 21 | void __init check_acpi_pci(void) |
| 22 | { |
| 23 | int num,slot,func; |
| 24 | |
| 25 | /* Assume the machine supports type 1. If not it will |
| 26 | always read ffffffff and should not have any side effect. */ |
| 27 | |
| 28 | /* Poor man's PCI discovery */ |
| 29 | for (num = 0; num < 32; num++) { |
| 30 | for (slot = 0; slot < 32; slot++) { |
| 31 | for (func = 0; func < 8; func++) { |
| 32 | u32 class; |
| 33 | u32 vendor; |
| 34 | class = read_pci_config(num,slot,func, |
| 35 | PCI_CLASS_REVISION); |
| 36 | if (class == 0xffffffff) |
| 37 | break; |
| 38 | |
| 39 | if ((class >> 16) != PCI_CLASS_BRIDGE_PCI) |
| 40 | continue; |
| 41 | |
| 42 | vendor = read_pci_config(num, slot, func, |
| 43 | PCI_VENDOR_ID); |
| 44 | |
| 45 | if (check_bridge(vendor&0xffff, vendor >> 16)) |
| 46 | return; |
| 47 | } |
| 48 | |
| 49 | } |
| 50 | } |
| 51 | } |