/* * legacy.c - traditional, old school PCI bus probing */ #include <linux/init.h> #include <linux/pci.h> #include <asm/pci_x86.h> /* * Discover remaining PCI buses in case there are peer host bridges. * We use the number of last PCI bus provided by the PCI BIOS. */ static void __devinit pcibios_fixup_peer_bridges(void) { int n, devfn; long node; if (pcibios_last_bus <= 0 || pcibios_last_bus > 0xff) return; DBG("PCI: Peer bridge fixup\n"); for (n=0; n <= pcibios_last_bus; n++) { u32 l; if (pci_find_bus(0, n)) continue; node = get_mp_bus_to_node(n); for (devfn = 0; devfn < 256; devfn += 8) { if (!raw_pci_read(0, n, devfn, PCI_VENDOR_ID, 2, &l) && l != 0x0000 && l != 0xffff) { DBG("Found device at %02x:%02x [%04x]\n", n, devfn, l); printk(KERN_INFO "PCI: Discovered peer bus %02x\n", n); pci_scan_bus_on_node(n, &pci_root_ops, node); break; } } } } static int __init pci_legacy_init(void) { if (!raw_pci_ops) { printk("PCI: System does not support PCI\n"); return 0; } if (pcibios_scanned++) return 0; printk("PCI: Probing PCI hardware\n"); pci_root_bus = pcibios_scan_root(0); if (pci_root_bus) pci_bus_add_devices(pci_root_bus); pcibios_fixup_peer_bridges(); return 0; } int __init pci_subsys_init(void) { #ifdef CONFIG_X86_NUMAQ pci_numaq_init(); #endif #ifdef CONFIG_ACPI pci_acpi_init(); #endif #ifdef CONFIG_X86_VISWS pci_visws_init(); #endif pci_legacy_init(); pcibios_irq_init(); pcibios_init(); return 0; } subsys_initcall(pci_subsys_init);