xref: /openbmc/linux/arch/x86/kernel/cpu/mce/winchip.c (revision 2cf1c348)
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: */
20 noinstr 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 */
29 void 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 }
42