1/*
 2 * legacy.c - traditional, old school PCI bus probing
 3 */
 4#include <linux/init.h>
 5#include <linux/export.h>
 6#include <linux/pci.h>
 7#include <asm/pci_x86.h>
 8
 9/*
10 * Discover remaining PCI buses in case there are peer host bridges.
11 * We use the number of last PCI bus provided by the PCI BIOS.
12 */
13static void pcibios_fixup_peer_bridges(void)
14{
15	int n;
16
17	if (pcibios_last_bus <= 0 || pcibios_last_bus > 0xff)
18		return;
19	DBG("PCI: Peer bridge fixup\n");
20
21	for (n=0; n <= pcibios_last_bus; n++)
22		pcibios_scan_specific_bus(n);
23}
24
25int __init pci_legacy_init(void)
26{
27	if (!raw_pci_ops) {
28		printk("PCI: System does not support PCI\n");
29		return 0;
30	}
31
32	printk("PCI: Probing PCI hardware\n");
33	pcibios_scan_root(0);
34	return 0;
35}
36
37void pcibios_scan_specific_bus(int busn)
38{
39	int devfn;
 
40	u32 l;
41
42	if (pci_find_bus(0, busn))
43		return;
44
 
45	for (devfn = 0; devfn < 256; devfn += 8) {
46		if (!raw_pci_read(0, busn, devfn, PCI_VENDOR_ID, 2, &l) &&
47		    l != 0x0000 && l != 0xffff) {
48			DBG("Found device at %02x:%02x [%04x]\n", busn, devfn, l);
49			printk(KERN_INFO "PCI: Discovered peer bus %02x\n", busn);
50			pcibios_scan_root(busn);
51			return;
52		}
53	}
54}
55EXPORT_SYMBOL_GPL(pcibios_scan_specific_bus);
56
57static int __init pci_subsys_init(void)
58{
59	/*
60	 * The init function returns an non zero value when
61	 * pci_legacy_init should be invoked.
62	 */
63	if (x86_init.pci.init())
64		pci_legacy_init();
65
66	pcibios_fixup_peer_bridges();
67	x86_init.pci.init_irq();
68	pcibios_init();
69
70	return 0;
71}
72subsys_initcall(pci_subsys_init);

 1/*
 2 * legacy.c - traditional, old school PCI bus probing
 3 */
 4#include <linux/init.h>
 5#include <linux/export.h>
 6#include <linux/pci.h>
 7#include <asm/pci_x86.h>
 8
 9/*
10 * Discover remaining PCI buses in case there are peer host bridges.
11 * We use the number of last PCI bus provided by the PCI BIOS.
12 */
13static void __devinit pcibios_fixup_peer_bridges(void)
14{
15	int n;
16
17	if (pcibios_last_bus <= 0 || pcibios_last_bus > 0xff)
18		return;
19	DBG("PCI: Peer bridge fixup\n");
20
21	for (n=0; n <= pcibios_last_bus; n++)
22		pcibios_scan_specific_bus(n);
23}
24
25int __init pci_legacy_init(void)
26{
27	if (!raw_pci_ops) {
28		printk("PCI: System does not support PCI\n");
29		return 0;
30	}
31
32	printk("PCI: Probing PCI hardware\n");
33	pci_root_bus = pcibios_scan_root(0);
34	return 0;
35}
36
37void __devinit pcibios_scan_specific_bus(int busn)
38{
39	int devfn;
40	long node;
41	u32 l;
42
43	if (pci_find_bus(0, busn))
44		return;
45
46	node = get_mp_bus_to_node(busn);
47	for (devfn = 0; devfn < 256; devfn += 8) {
48		if (!raw_pci_read(0, busn, devfn, PCI_VENDOR_ID, 2, &l) &&
49		    l != 0x0000 && l != 0xffff) {
50			DBG("Found device at %02x:%02x [%04x]\n", busn, devfn, l);
51			printk(KERN_INFO "PCI: Discovered peer bus %02x\n", busn);
52			pci_scan_bus_on_node(busn, &pci_root_ops, node);
53			return;
54		}
55	}
56}
57EXPORT_SYMBOL_GPL(pcibios_scan_specific_bus);
58
59int __init pci_subsys_init(void)
60{
61	/*
62	 * The init function returns an non zero value when
63	 * pci_legacy_init should be invoked.
64	 */
65	if (x86_init.pci.init())
66		pci_legacy_init();
67
68	pcibios_fixup_peer_bridges();
69	x86_init.pci.init_irq();
70	pcibios_init();
71
72	return 0;
73}
74subsys_initcall(pci_subsys_init);