projects / mirror_ubuntu-jammy-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* |
| 2 | * legacy.c - traditional, old school PCI bus probing | |
| 3 | */ | |
| 4 | #include <linux/init.h> | |
| 5 | #include <linux/pci.h> | |
| 6 | #include "pci.h" | |
| 7 | ||
| 8 | /* | |
| 9 | * Discover remaining PCI buses in case there are peer host bridges. | |
| 10 | * We use the number of last PCI bus provided by the PCI BIOS. | |
| 11 | */ | |
| 12 | static void __devinit pcibios_fixup_peer_bridges(void) | |
| 13 | { | |
| 14 | int n, devfn; | |
| 15 | ||
| 16 | if (pcibios_last_bus <= 0 || pcibios_last_bus >= 0xff) | |
| 17 | return; | |
| 18 | DBG("PCI: Peer bridge fixup\n"); | |
| 19 | ||
| 20 | for (n=0; n <= pcibios_last_bus; n++) { | |
| 21 | u32 l; | |
| 22 | if (pci_find_bus(0, n)) | |
| 23 | continue; | |
| 24 | for (devfn = 0; devfn < 256; devfn += 8) { | |
| b6ce068a | 25 | if (!raw_pci_read(0, n, devfn, PCI_VENDOR_ID, 2, &l) && |
| 1da177e4 LT |
26 | l != 0x0000 && l != 0xffff) { |
| 27 | DBG("Found device at %02x:%02x [%04x]\n", n, devfn, l); | |
| 28 | printk(KERN_INFO "PCI: Discovered peer bus %02x\n", n); | |
| 73c59afc | 29 | pci_scan_bus_with_sysdata(n); |
| 1da177e4 LT |
30 | break; |
| 31 | } | |
| 32 | } | |
| 33 | } | |
| 34 | } | |
| 35 | ||
| 36 | static int __init pci_legacy_init(void) | |
| 37 | { | |
| 38 | if (!raw_pci_ops) { | |
| 39 | printk("PCI: System does not support PCI\n"); | |
| 40 | return 0; | |
| 41 | } | |
| 42 | ||
| 43 | if (pcibios_scanned++) | |
| 44 | return 0; | |
| 45 | ||
| 46 | printk("PCI: Probing PCI hardware\n"); | |
| 47 | pci_root_bus = pcibios_scan_root(0); | |
| c431ada4 RS |
48 | if (pci_root_bus) |
| 49 | pci_bus_add_devices(pci_root_bus); | |
| 1da177e4 LT |
50 | |
| 51 | pcibios_fixup_peer_bridges(); | |
| 52 | ||
| 53 | return 0; | |
| 54 | } | |
| 55 | ||
| 56 | subsys_initcall(pci_legacy_init); |