arch/x86/kernel/cpu/mcheck/mce_32.c

   1 /*
   2  * mce.c - x86 Machine Check Exception Reporting
   3  * (c) 2002 Alan Cox <alan@lxorguk.ukuu.org.uk>, Dave Jones <davej@redhat.com>
   4  */
   5
   6 #include <linux/init.h>
   7 #include <linux/types.h>
   8 #include <linux/kernel.h>
   9 #include <linux/module.h>
  10 #include <linux/smp.h>
  11 #include <linux/thread_info.h>
  12
  13 #include <asm/processor.h>
  14 #include <asm/system.h>
  15 #include <asm/mce.h>
  16
  17 #include "mce.h"
  18
  19 int mce_disabled;
  20 int nr_mce_banks;
  21
  22 EXPORT_SYMBOL_GPL(nr_mce_banks);        /* non-fatal.o */
  23
  24 /* Handle unconfigured int18 (should never happen) */
  25 static void unexpected_machine_check(struct pt_regs *regs, long error_code)
  26 {
  27         printk(KERN_ERR "CPU#%d: Unexpected int18 (Machine Check).\n", smp_processor_id());
  28 }
  29
  30 /* Call the installed machine check handler for this CPU setup. */
  31 void (*machine_check_vector)(struct pt_regs *, long error_code) = unexpected_machine_check;
  32
  33 /* This has to be run for each processor */
  34 void mcheck_init(struct cpuinfo_x86 *c)
  35 {
  36         if (mce_disabled == 1)
  37                 return;
  38
  39         switch (c->x86_vendor) {
  40         case X86_VENDOR_AMD:
  41                 amd_mcheck_init(c);
  42                 break;
  43
  44         case X86_VENDOR_INTEL:
  45                 if (c->x86 == 5)
  46                         intel_p5_mcheck_init(c);
  47                 if (c->x86 == 6)
  48                         intel_p6_mcheck_init(c);
  49                 if (c->x86 == 15)
  50                         intel_p4_mcheck_init(c);
  51                 break;
  52
  53         case X86_VENDOR_CENTAUR:
  54                 if (c->x86 == 5)
  55                         winchip_mcheck_init(c);
  56                 break;
  57
  58         default:
  59                 break;
  60         }
  61 }
  62
  63 static unsigned long old_cr4 __initdata;
  64
  65 void __init stop_mce(void)
  66 {
  67         old_cr4 = read_cr4();
  68         clear_in_cr4(X86_CR4_MCE);
  69 }
  70
  71 void __init restart_mce(void)
  72 {
  73         if (old_cr4 & X86_CR4_MCE)
  74                 set_in_cr4(X86_CR4_MCE);
  75 }
  76
  77 static int __init mcheck_disable(char *str)
  78 {
  79         mce_disabled = 1;
  80         return 1;
  81 }
  82
  83 static int __init mcheck_enable(char *str)
  84 {
  85         mce_disabled = -1;
  86         return 1;
  87 }
  88
  89 __setup("nomce", mcheck_disable);
  90 __setup("mce", mcheck_enable);