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/init.h>
   9#include <linux/smp.h>
  10
  11#include <asm/processor.h>
  12#include <asm/mce.h>
  13#include <asm/msr.h>
  14
  15/* By default disabled */
  16int mce_p5_enabled __read_mostly;
  17
  18/* Machine check handler for Pentium class Intel CPUs: */
  19static void pentium_machine_check(struct pt_regs *regs, long error_code)
  20{
  21        u32 loaddr, hi, lotype;
  22
  23        rdmsr(MSR_IA32_P5_MC_ADDR, loaddr, hi);
  24        rdmsr(MSR_IA32_P5_MC_TYPE, lotype, hi);
  25
  26        printk(KERN_EMERG
  27                "CPU#%d: Machine Check Exception:  0x%8X (type 0x%8X).\n",
  28                smp_processor_id(), loaddr, lotype);
  29
  30        if (lotype & (1<<5)) {
  31                printk(KERN_EMERG
  32                        "CPU#%d: Possible thermal failure (CPU on fire ?).\n",
  33                        smp_processor_id());
  34        }
  35
  36        add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
  37}
  38
  39/* Set up machine check reporting for processors with Intel style MCE: */
  40void intel_p5_mcheck_init(struct cpuinfo_x86 *c)
  41{
  42        u32 l, h;
  43
  44        /* Default P5 to off as its often misconnected: */
  45        if (!mce_p5_enabled)
  46                return;
  47
  48        /* Check for MCE support: */
  49        if (!cpu_has(c, X86_FEATURE_MCE))
  50                return;
  51
  52        machine_check_vector = pentium_machine_check;
  53        /* Make sure the vector pointer is visible before we enable MCEs: */
  54        wmb();
  55
  56        /* Read registers before enabling: */
  57        rdmsr(MSR_IA32_P5_MC_ADDR, l, h);
  58        rdmsr(MSR_IA32_P5_MC_TYPE, l, h);
  59        printk(KERN_INFO
  60               "Intel old style machine check architecture supported.\n");
  61
  62        /* Enable MCE: */
  63        set_in_cr4(X86_CR4_MCE);
  64        printk(KERN_INFO
  65               "Intel old style machine check reporting enabled on CPU#%d.\n",
  66               smp_processor_id());
  67}
  68