1 /* Copyright 2003 Andi Kleen, SuSE Labs.
2 * Subject to the GNU Public License, v.2
4 * Generic x86 APIC driver probe layer.
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 <asm/fixmap.h>
13 #include <asm/mpspec.h>
14 #include <asm/apicdef.h>
15 #include <asm/genapic.h>
17 extern struct genapic apic_summit
;
18 extern struct genapic apic_bigsmp
;
19 extern struct genapic apic_es7000
;
20 extern struct genapic apic_default
;
22 struct genapic
*genapic
= &apic_default
;
24 struct genapic
*apic_probe
[] __initdata
= {
28 &apic_default
, /* must be last */
32 static int cmdline_apic
;
34 void __init
generic_bigsmp_probe(void)
37 * This routine is used to switch to bigsmp mode when
38 * - There is no apic= option specified by the user
39 * - generic_apic_probe() has choosen apic_default as the sub_arch
40 * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support
43 if (!cmdline_apic
&& genapic
== &apic_default
)
44 if (apic_bigsmp
.probe()) {
45 genapic
= &apic_bigsmp
;
46 printk(KERN_INFO
"Overriding APIC driver with %s\n",
51 void __init
generic_apic_probe(char *command_line
)
57 s
= strstr(command_line
, "apic=");
58 if (s
&& (s
== command_line
|| isspace(s
[-1]))) {
59 char *p
= strchr(s
, ' '), old
;
64 for (i
= 0; !changed
&& apic_probe
[i
]; i
++) {
65 if (!strcmp(apic_probe
[i
]->name
, s
+5)) {
67 genapic
= apic_probe
[i
];
71 printk(KERN_ERR
"Unknown genapic `%s' specified.\n", s
);
73 cmdline_apic
= changed
;
75 for (i
= 0; !changed
&& apic_probe
[i
]; i
++) {
76 if (apic_probe
[i
]->probe()) {
78 genapic
= apic_probe
[i
];
81 /* Not visible without early console */
83 panic("Didn't find an APIC driver");
85 printk(KERN_INFO
"Using APIC driver %s\n", genapic
->name
);
88 /* These functions can switch the APIC even after the initial ->probe() */
90 int __init
mps_oem_check(struct mp_config_table
*mpc
, char *oem
, char *productid
)
93 for (i
= 0; apic_probe
[i
]; ++i
) {
94 if (apic_probe
[i
]->mps_oem_check(mpc
,oem
,productid
)) {
96 genapic
= apic_probe
[i
];
97 printk(KERN_INFO
"Switched to APIC driver `%s'.\n",
106 int __init
acpi_madt_oem_check(char *oem_id
, char *oem_table_id
)
109 for (i
= 0; apic_probe
[i
]; ++i
) {
110 if (apic_probe
[i
]->acpi_madt_oem_check(oem_id
, oem_table_id
)) {
112 genapic
= apic_probe
[i
];
113 printk(KERN_INFO
"Switched to APIC driver `%s'.\n",
122 int hard_smp_processor_id(void)
124 return genapic
->get_apic_id(*(unsigned long *)(APIC_BASE
+APIC_ID
));