LXR linux/arch/x86/kernel/cpu/mcheck/p5.c

   1/*
   2 * P5 specific Machine Check Exception Reporting
   3 * (C) Copyright 2002 Alan Cox <alan@lxorguk.ukuu.org.uk>
   4 */
   5#include <linux/interrupt.h>
   6#include <linux/kernel.h>
   7#include <linux/types.h>
   8#include <linux/smp.h>
   9
  10#include <asm/processor.h>
  11#include <asm/mce.h>
  12#include <asm/msr.h>
  13
  14/* By default disabled */
  15int mce_p5_enabled __read_mostly;
  16
  17/* Machine check handler for Pentium class Intel CPUs: */
  18static void pentium_machine_check(struct pt_regs *regs, long error_code)
  19{
  20        u32 loaddr, hi, lotype;
  21
  22        rdmsr(MSR_IA32_P5_MC_ADDR, loaddr, hi);
  23        rdmsr(MSR_IA32_P5_MC_TYPE, lotype, hi);
  24
  25        printk(KERN_EMERG
  26                "CPU#%d: Machine Check Exception:  0x%8X (type 0x%8X).\n",
  27                smp_processor_id(), loaddr, lotype);
  28
  29        if (lotype & (1<<5)) {
  30                printk(KERN_EMERG
  31                        "CPU#%d: Possible thermal failure (CPU on fire ?).\n",
  32                        smp_processor_id());
  33        }
  34
  35        add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
  36}
  37
  38/* Set up machine check reporting for processors with Intel style MCE: */
  39void intel_p5_mcheck_init(struct cpuinfo_x86 *c)
  40{
  41        u32 l, h;
  42
  43        /* Default P5 to off as its often misconnected: */
  44        if (!mce_p5_enabled)
  45                return;
  46
  47        /* Check for MCE support: */
  48        if (!cpu_has(c, X86_FEATURE_MCE))
  49                return;
  50
  51        machine_check_vector = pentium_machine_check;
  52        /* Make sure the vector pointer is visible before we enable MCEs: */
  53        wmb();
  54
  55        /* Read registers before enabling: */
  56        rdmsr(MSR_IA32_P5_MC_ADDR, l, h);
  57        rdmsr(MSR_IA32_P5_MC_TYPE, l, h);
  58        printk(KERN_INFO
  59               "Intel old style machine check architecture supported.\n");
  60
  61        /* Enable MCE: */
  62        set_in_cr4(X86_CR4_MCE);
  63        printk(KERN_INFO
  64               "Intel old style machine check reporting enabled on CPU#%d.\n",
  65               smp_processor_id());
  66}
  67