LXR linux/arch/x86/kernel/cpu/mce/winchip.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * IDT Winchip specific Machine Check Exception Reporting
   4 * (C) Copyright 2002 Alan Cox <alan@lxorguk.ukuu.org.uk>
   5 */
   6#include <linux/interrupt.h>
   7#include <linux/kernel.h>
   8#include <linux/types.h>
   9
  10#include <asm/processor.h>
  11#include <asm/traps.h>
  12#include <asm/tlbflush.h>
  13#include <asm/mce.h>
  14#include <asm/msr.h>
  15
  16#include "internal.h"
  17
  18/* Machine check handler for WinChip C6: */
  19static void winchip_machine_check(struct pt_regs *regs, long error_code)
  20{
  21        ist_enter(regs);
  22
  23        pr_emerg("CPU0: Machine Check Exception.\n");
  24        add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
  25
  26        ist_exit(regs);
  27}
  28
  29/* Set up machine check reporting on the Winchip C6 series */
  30void winchip_mcheck_init(struct cpuinfo_x86 *c)
  31{
  32        u32 lo, hi;
  33
  34        machine_check_vector = winchip_machine_check;
  35        /* Make sure the vector pointer is visible before we enable MCEs: */
  36        wmb();
  37
  38        rdmsr(MSR_IDT_FCR1, lo, hi);
  39        lo |= (1<<2);   /* Enable EIERRINT (int 18 MCE) */
  40        lo &= ~(1<<4);  /* Enable MCE */
  41        wrmsr(MSR_IDT_FCR1, lo, hi);
  42
  43        cr4_set_bits(X86_CR4_MCE);
  44
  45        pr_info("Winchip machine check reporting enabled on CPU#0.\n");
  46}
  47