Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
[linux-2.6] / arch / x86 / kernel / cpu / mcheck / non-fatal.c
1 /*
2  * Non Fatal Machine Check Exception Reporting
3  *
4  * (C) Copyright 2002 Dave Jones. <davej@redhat.com>
5  *
6  * This file contains routines to check for non-fatal MCEs every 15s
7  *
8  */
9
10 #include <linux/init.h>
11 #include <linux/types.h>
12 #include <linux/kernel.h>
13 #include <linux/jiffies.h>
14 #include <linux/workqueue.h>
15 #include <linux/interrupt.h>
16 #include <linux/smp.h>
17 #include <linux/module.h>
18
19 #include <asm/processor.h>
20 #include <asm/system.h>
21 #include <asm/msr.h>
22
23 #include "mce.h"
24
25 static int firstbank;
26
27 #define MCE_RATE        15*HZ   /* timer rate is 15s */
28
29 static void mce_checkregs(void *info)
30 {
31         u32 low, high;
32         int i;
33
34         for (i = firstbank; i < nr_mce_banks; i++) {
35                 rdmsr(MSR_IA32_MC0_STATUS+i*4, low, high);
36
37                 if (high & (1<<31)) {
38                         printk(KERN_INFO "MCE: The hardware reports a non "
39                                 "fatal, correctable incident occurred on "
40                                 "CPU %d.\n",
41                                 smp_processor_id());
42                         printk(KERN_INFO "Bank %d: %08x%08x\n", i, high, low);
43
44                         /*
45                          * Scrub the error so we don't pick it up in MCE_RATE
46                          * seconds time.
47                          */
48                         wrmsr(MSR_IA32_MC0_STATUS+i*4, 0UL, 0UL);
49
50                         /* Serialize */
51                         wmb();
52                         add_taint(TAINT_MACHINE_CHECK);
53                 }
54         }
55 }
56
57 static void mce_work_fn(struct work_struct *work);
58 static DECLARE_DELAYED_WORK(mce_work, mce_work_fn);
59
60 static void mce_work_fn(struct work_struct *work)
61 {
62         on_each_cpu(mce_checkregs, NULL, 1);
63         schedule_delayed_work(&mce_work, round_jiffies_relative(MCE_RATE));
64 }
65
66 static int __init init_nonfatal_mce_checker(void)
67 {
68         struct cpuinfo_x86 *c = &boot_cpu_data;
69
70         /* Check for MCE support */
71         if (!cpu_has(c, X86_FEATURE_MCE))
72                 return -ENODEV;
73
74         /* Check for PPro style MCA */
75         if (!cpu_has(c, X86_FEATURE_MCA))
76                 return -ENODEV;
77
78         /* Some Athlons misbehave when we frob bank 0 */
79         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
80                 boot_cpu_data.x86 == 6)
81                         firstbank = 1;
82         else
83                         firstbank = 0;
84
85         /*
86          * Check for non-fatal errors every MCE_RATE s
87          */
88         schedule_delayed_work(&mce_work, round_jiffies_relative(MCE_RATE));
89         printk(KERN_INFO "Machine check exception polling timer started.\n");
90         return 0;
91 }
92 module_init(init_nonfatal_mce_checker);
93
94 MODULE_LICENSE("GPL");