2 * P6 specific Machine Check Exception Reporting
3 * (C) Copyright 2002 Alan Cox <alan@redhat.com>
6 #include <linux/init.h>
7 #include <linux/types.h>
8 #include <linux/kernel.h>
9 #include <linux/interrupt.h>
10 #include <linux/smp.h>
12 #include <asm/processor.h>
13 #include <asm/system.h>
18 /* Machine Check Handler For PII/PIII */
19 static fastcall void intel_machine_check(struct pt_regs * regs, long error_code)
22 u32 alow, ahigh, high, low;
26 rdmsr (MSR_IA32_MCG_STATUS, mcgstl, mcgsth);
27 if (mcgstl & (1<<0)) /* Recoverable ? */
30 printk (KERN_EMERG "CPU %d: Machine Check Exception: %08x%08x\n",
31 smp_processor_id(), mcgsth, mcgstl);
33 for (i=0; i<nr_mce_banks; i++) {
34 rdmsr (MSR_IA32_MC0_STATUS+i*4,low, high);
40 printk (KERN_EMERG "Bank %d: %08x%08x", i, high, low);
43 rdmsr (MSR_IA32_MC0_MISC+i*4, alow, ahigh);
44 printk ("[%08x%08x]", ahigh, alow);
47 rdmsr (MSR_IA32_MC0_ADDR+i*4, alow, ahigh);
48 printk (" at %08x%08x", ahigh, alow);
55 panic ("CPU context corrupt");
57 panic ("Unable to continue");
59 printk (KERN_EMERG "Attempting to continue.\n");
61 * Do not clear the MSR_IA32_MCi_STATUS if the error is not
62 * recoverable/continuable.This will allow BIOS to look at the MSRs
63 * for errors if the OS could not log the error.
65 for (i=0; i<nr_mce_banks; i++) {
67 msr = MSR_IA32_MC0_STATUS+i*4;
68 rdmsr (msr,low, high);
71 wrmsr (msr, 0UL, 0UL);
74 add_taint(TAINT_MACHINE_CHECK);
78 wrmsr (MSR_IA32_MCG_STATUS,mcgstl, mcgsth);
81 /* Set up machine check reporting for processors with Intel style MCE */
82 void intel_p6_mcheck_init(struct cpuinfo_x86 *c)
87 /* Check for MCE support */
88 if (!cpu_has(c, X86_FEATURE_MCE))
91 /* Check for PPro style MCA */
92 if (!cpu_has(c, X86_FEATURE_MCA))
95 /* Ok machine check is available */
96 machine_check_vector = intel_machine_check;
99 printk (KERN_INFO "Intel machine check architecture supported.\n");
100 rdmsr (MSR_IA32_MCG_CAP, l, h);
101 if (l & (1<<8)) /* Control register present ? */
102 wrmsr(MSR_IA32_MCG_CTL, 0xffffffff, 0xffffffff);
103 nr_mce_banks = l & 0xff;
106 * Following the example in IA-32 SDM Vol 3:
107 * - MC0_CTL should not be written
108 * - Status registers on all banks should be cleared on reset
110 for (i=1; i<nr_mce_banks; i++)
111 wrmsr (MSR_IA32_MC0_CTL+4*i, 0xffffffff, 0xffffffff);
113 for (i=0; i<nr_mce_banks; i++)
114 wrmsr (MSR_IA32_MC0_STATUS+4*i, 0x0, 0x0);
116 set_in_cr4 (X86_CR4_MCE);
117 printk (KERN_INFO "Intel machine check reporting enabled on CPU#%d.\n",