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 static void winchip_machine_check(struct pt_regs *regs, long error_code) 21 { 22 nmi_enter(); 23 24 pr_emerg("CPU0: Machine Check Exception.\n"); 25 add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE); 26 27 nmi_exit(); 28 } 29 30 /* Set up machine check reporting on the Winchip C6 series */ 31 void winchip_mcheck_init(struct cpuinfo_x86 *c) 32 { 33 u32 lo, hi; 34 35 machine_check_vector = winchip_machine_check; 36 /* Make sure the vector pointer is visible before we enable MCEs: */ 37 wmb(); 38 39 rdmsr(MSR_IDT_FCR1, lo, hi); 40 lo |= (1<<2); /* Enable EIERRINT (int 18 MCE) */ 41 lo &= ~(1<<4); /* Enable MCE */ 42 wrmsr(MSR_IDT_FCR1, lo, hi); 43 44 cr4_set_bits(X86_CR4_MCE); 45 46 pr_info("Winchip machine check reporting enabled on CPU#0.\n"); 47 } 48