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#include <linux/hardirq.h>
10
11#include <asm/processor.h>
12#include <asm/traps.h>
13#include <asm/tlbflush.h>
14#include <asm/mce.h>
15#include <asm/msr.h>
16
17#include "internal.h"
18
19/* Machine check handler for WinChip C6: */
20noinstr void winchip_machine_check(struct pt_regs *regs)
21{
22	instrumentation_begin();
23	pr_emerg("CPU0: Machine Check Exception.\n");
24	add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
25	instrumentation_end();
26}
27
28/* Set up machine check reporting on the Winchip C6 series */
29void winchip_mcheck_init(struct cpuinfo_x86 *c)
30{
31	u32 lo, hi;
32
33	rdmsr(MSR_IDT_FCR1, lo, hi);
34	lo |= (1<<2);	/* Enable EIERRINT (int 18 MCE) */
35	lo &= ~(1<<4);	/* Enable MCE */
36	wrmsr(MSR_IDT_FCR1, lo, hi);
37
38	cr4_set_bits(X86_CR4_MCE);
39
40	pr_info("Winchip machine check reporting enabled on CPU#0.\n");
41}