arch/i386/mach-generic/probe.c

   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/config.h>
   7 #include <linux/threads.h>
   8 #include <linux/cpumask.h>
   9 #include <linux/string.h>
  10 #include <linux/kernel.h>
  11 #include <linux/ctype.h>
  12 #include <linux/init.h>
  13 #include <asm/fixmap.h>
  14 #include <asm/mpspec.h>
  15 #include <asm/apicdef.h>
  16 #include <asm/genapic.h>
  17
  18 extern struct genapic apic_summit;
  19 extern struct genapic apic_bigsmp;
  20 extern struct genapic apic_es7000;
  21 extern struct genapic apic_default;
  22
  23 struct genapic *genapic = &apic_default;
  24
  25 struct genapic *apic_probe[] __initdata = {
  26         &apic_summit,
  27         &apic_bigsmp,
  28         &apic_es7000,
  29         &apic_default,  /* must be last */
  30         NULL,
  31 };
  32
  33 void __init generic_apic_probe(char *command_line)
  34 {
  35         char *s;
  36         int i;
  37         int changed = 0;
  38
  39         s = strstr(command_line, "apic=");
  40         if (s && (s == command_line || isspace(s[-1]))) {
  41                 char *p = strchr(s, ' '), old;
  42                 if (!p)
  43                         p = strchr(s, '\0');
  44                 old = *p;
  45                 *p = 0;
  46                 for (i = 0; !changed && apic_probe[i]; i++) {
  47                         if (!strcmp(apic_probe[i]->name, s+5)) {
  48                                 changed = 1;
  49                                 genapic = apic_probe[i];
  50                         }
  51                 }
  52                 if (!changed)
  53                         printk(KERN_ERR "Unknown genapic `%s' specified.\n", s);
  54                 *p = old;
  55         }
  56         for (i = 0; !changed && apic_probe[i]; i++) {
  57                 if (apic_probe[i]->probe()) {
  58                         changed = 1;
  59                         genapic = apic_probe[i];
  60                 }
  61         }
  62         /* Not visible without early console */
  63         if (!changed)
  64                 panic("Didn't find an APIC driver");
  65
  66         printk(KERN_INFO "Using APIC driver %s\n", genapic->name);
  67 }
  68
  69 /* These functions can switch the APIC even after the initial ->probe() */
  70
  71 int __init mps_oem_check(struct mp_config_table *mpc, char *oem, char *productid)
  72 {
  73         int i;
  74         for (i = 0; apic_probe[i]; ++i) {
  75                 if (apic_probe[i]->mps_oem_check(mpc,oem,productid)) {
  76                         genapic = apic_probe[i];
  77                         printk(KERN_INFO "Switched to APIC driver `%s'.\n",
  78                                genapic->name);
  79                         return 1;
  80                 }
  81         }
  82         return 0;
  83 }
  84
  85 int __init acpi_madt_oem_check(char *oem_id, char *oem_table_id)
  86 {
  87         int i;
  88         for (i = 0; apic_probe[i]; ++i) {
  89                 if (apic_probe[i]->acpi_madt_oem_check(oem_id, oem_table_id)) {
  90                         genapic = apic_probe[i];
  91                         printk(KERN_INFO "Switched to APIC driver `%s'.\n",
  92                                genapic->name);
  93                         return 1;
  94                 }
  95         }
  96         return 0;
  97 }
  98
  99 int hard_smp_processor_id(void)
 100 {
 101         return genapic->get_apic_id(*(unsigned long *)(APIC_BASE+APIC_ID));
 102 }