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);
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}