1/*
2 * arch/i386/kernel/topology.c - Populate sysfs with topology information
3 *
4 * Written by: Matthew Dobson, IBM Corporation
5 * Original Code: Paul Dorwin, IBM Corporation, Patrick Mochel, OSDL
6 *
7 * Copyright (C) 2002, IBM Corp.
8 *
9 * All rights reserved.
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful, but
17 * WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
19 * NON INFRINGEMENT.  See the GNU General Public License for more
20 * details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 *
26 * Send feedback to <colpatch@us.ibm.com>
27 */
28#include <linux/init.h>
29#include <linux/smp.h>
30#include <linux/nodemask.h>
31#include <linux/mmzone.h>
32#include <asm/cpu.h>
33
34static struct i386_cpu cpu_devices[NR_CPUS];
35
36int arch_register_cpu(int num)
37{
38	/*
39	 * CPU0 cannot be offlined due to several
40	 * restrictions and assumptions in kernel. This basically
41	 * doesnt add a control file, one cannot attempt to offline
42	 * BSP.
43	 *
44	 * Also certain PCI quirks require not to enable hotplug control
45	 * for all CPU's.
46	 */
47	if (num && enable_cpu_hotplug)
48		cpu_devices[num].cpu.hotpluggable = 1;
49
50	return register_cpu(&cpu_devices[num].cpu, num);
51}
52
53#ifdef CONFIG_HOTPLUG_CPU
54int enable_cpu_hotplug = 1;
55
56void arch_unregister_cpu(int num) {
57	return unregister_cpu(&cpu_devices[num].cpu);
58}
59EXPORT_SYMBOL(arch_register_cpu);
60EXPORT_SYMBOL(arch_unregister_cpu);
61#endif /*CONFIG_HOTPLUG_CPU*/
62
63static int __init topology_init(void)
64{
65	int i;
66
67#ifdef CONFIG_NUMA
68	for_each_online_node(i)
69		register_one_node(i);
70#endif /* CONFIG_NUMA */
71
72	for_each_present_cpu(i)
73		arch_register_cpu(i);
74	return 0;
75}
76
77subsys_initcall(topology_init);
78