1/*
2 * Copyright 2004 James Cleverdon, IBM.
3 * Subject to the GNU Public License, v.2
4 *
5 * Generic APIC sub-arch probe layer.
6 *
7 * Hacked for x86-64 by James Cleverdon from i386 architecture code by
8 * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
9 * James Cleverdon.
10 */
11#include <linux/threads.h>
12#include <linux/cpumask.h>
13#include <linux/string.h>
14#include <linux/module.h>
15#include <linux/kernel.h>
16#include <linux/ctype.h>
17#include <linux/init.h>
18
19#include <asm/smp.h>
20#include <asm/ipi.h>
21#include <asm/genapic.h>
22
23#ifdef CONFIG_ACPI
24#include <acpi/acpi_bus.h>
25#endif
26
27/* which logical CPU number maps to which CPU (physical APIC ID) */
28u8 x86_cpu_to_apicid[NR_CPUS] __read_mostly
29					= { [0 ... NR_CPUS-1] = BAD_APICID };
30EXPORT_SYMBOL(x86_cpu_to_apicid);
31
32u8 x86_cpu_to_log_apicid[NR_CPUS]	= { [0 ... NR_CPUS-1] = BAD_APICID };
33
34struct genapic __read_mostly *genapic = &apic_flat;
35
36/*
37 * Check the APIC IDs in bios_cpu_apicid and choose the APIC mode.
38 */
39void __init setup_apic_routing(void)
40{
41#ifdef CONFIG_ACPI
42	/*
43	 * Quirk: some x86_64 machines can only use physical APIC mode
44	 * regardless of how many processors are present (x86_64 ES7000
45	 * is an example).
46	 */
47	if (acpi_gbl_FADT.header.revision > FADT2_REVISION_ID &&
48			(acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL))
49		genapic = &apic_physflat;
50	else
51#endif
52
53	if (cpus_weight(cpu_possible_map) <= 8)
54		genapic = &apic_flat;
55	else
56		genapic = &apic_physflat;
57
58	printk(KERN_INFO "Setting APIC routing to %s\n", genapic->name);
59}
60
61/* Same for both flat and physical. */
62
63void send_IPI_self(int vector)
64{
65	__send_IPI_shortcut(APIC_DEST_SELF, vector, APIC_DEST_PHYSICAL);
66}
67