arch/x86/mach-generic/probe.c

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