1/* Copyright 2003 Andi Kleen, SuSE Labs.
2 * Subject to the GNU Public License, v.2
3 *
4 * Generic x86 APIC driver probe layer.
5 */
6#include <linux/threads.h>
7#include <linux/cpumask.h>
8#include <linux/string.h>
9#include <linux/kernel.h>
10#include <linux/ctype.h>
11#include <linux/init.h>
12#include <linux/errno.h>
13#include <asm/fixmap.h>
14#include <asm/mpspec.h>
15#include <asm/apicdef.h>
16#include <asm/genapic.h>
17
18extern struct genapic apic_summit;
19extern struct genapic apic_bigsmp;
20extern struct genapic apic_es7000;
21extern struct genapic apic_default;
22
23struct genapic *genapic = &apic_default;
24
25struct genapic *apic_probe[] __initdata = {
26	&apic_summit,
27	&apic_bigsmp,
28	&apic_es7000,
29	&apic_default,	/* must be last */
30	NULL,
31};
32
33static int cmdline_apic __initdata;
34static int __init parse_apic(char *arg)
35{
36	int i;
37
38	if (!arg)
39		return -EINVAL;
40
41	for (i = 0; apic_probe[i]; i++) {
42		if (!strcmp(apic_probe[i]->name, arg)) {
43			genapic = apic_probe[i];
44			cmdline_apic = 1;
45			return 0;
46		}
47	}
48
49	/* Parsed again by __setup for debug/verbose */
50	return 0;
51}
52early_param("apic", parse_apic);
53
54void __init generic_bigsmp_probe(void)
55{
56	/*
57	 * This routine is used to switch to bigsmp mode when
58	 * - There is no apic= option specified by the user
59	 * - generic_apic_probe() has choosen apic_default as the sub_arch
60	 * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support
61	 */
62
63	if (!cmdline_apic && genapic == &apic_default)
64		if (apic_bigsmp.probe()) {
65			genapic = &apic_bigsmp;
66			printk(KERN_INFO "Overriding APIC driver with %s\n",
67			       genapic->name);
68		}
69}
70
71void __init generic_apic_probe(void)
72{
73	if (!cmdline_apic) {
74		int i;
75		for (i = 0; apic_probe[i]; i++) {
76			if (apic_probe[i]->probe()) {
77				genapic = apic_probe[i];
78				break;
79			}
80		}
81		/* Not visible without early console */
82		if (!apic_probe[i])
83			panic("Didn't find an APIC driver");
84	}
85	printk(KERN_INFO "Using APIC driver %s\n", genapic->name);
86}
87
88/* These functions can switch the APIC even after the initial ->probe() */
89
90int __init mps_oem_check(struct mp_config_table *mpc, char *oem, char *productid)
91{
92	int i;
93	for (i = 0; apic_probe[i]; ++i) {
94		if (apic_probe[i]->mps_oem_check(mpc,oem,productid)) {
95			if (!cmdline_apic) {
96				genapic = apic_probe[i];
97				printk(KERN_INFO "Switched to APIC driver `%s'.\n",
98				       genapic->name);
99			}
100			return 1;
101		}
102	}
103	return 0;
104}
105
106int __init acpi_madt_oem_check(char *oem_id, char *oem_table_id)
107{
108	int i;
109	for (i = 0; apic_probe[i]; ++i) {
110		if (apic_probe[i]->acpi_madt_oem_check(oem_id, oem_table_id)) {
111			if (!cmdline_apic) {
112				genapic = apic_probe[i];
113				printk(KERN_INFO "Switched to APIC driver `%s'.\n",
114				       genapic->name);
115			}
116			return 1;
117		}
118	}
119	return 0;
120}
121
122int hard_smp_processor_id(void)
123{
124	return genapic->get_apic_id(*(unsigned long *)(APIC_BASE+APIC_ID));
125}
126