1/* 2 * Copyright (c) 1991,1992,1995 Linus Torvalds 3 * Copyright (c) 1994 Alan Modra 4 * Copyright (c) 1995 Markus Kuhn 5 * Copyright (c) 1996 Ingo Molnar 6 * Copyright (c) 1998 Andrea Arcangeli 7 * Copyright (c) 2002,2006 Vojtech Pavlik 8 * Copyright (c) 2003 Andi Kleen 9 * 10 */ 11 12#include <linux/clockchips.h> 13#include <linux/interrupt.h> 14#include <linux/time.h> 15#include <linux/mca.h> 16 17#include <asm/vsyscall.h> 18#include <asm/x86_init.h> 19#include <asm/i8259.h> 20#include <asm/i8253.h> 21#include <asm/timer.h> 22#include <asm/hpet.h> 23#include <asm/time.h> 24 25#if defined(CONFIG_X86_32) && defined(CONFIG_X86_IO_APIC) 26int timer_ack; 27#endif 28 29#ifdef CONFIG_X86_64 30volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES; 31#endif 32 33unsigned long profile_pc(struct pt_regs *regs) 34{ 35 unsigned long pc = instruction_pointer(regs); 36 37 if (!user_mode_vm(regs) && in_lock_functions(pc)) { 38#ifdef CONFIG_FRAME_POINTER 39 return *(unsigned long *)(regs->bp + sizeof(long)); 40#else 41 unsigned long *sp = 42 (unsigned long *)kernel_stack_pointer(regs); 43 /* 44 * Return address is either directly at stack pointer 45 * or above a saved flags. Eflags has bits 22-31 zero, 46 * kernel addresses don't. 47 */ 48 if (sp[0] >> 22) 49 return sp[0]; 50 if (sp[1] >> 22) 51 return sp[1]; 52#endif 53 } 54 return pc; 55} 56EXPORT_SYMBOL(profile_pc); 57 58/* 59 * Default timer interrupt handler for PIT/HPET 60 */ 61static irqreturn_t timer_interrupt(int irq, void *dev_id) 62{ 63 /* Keep nmi watchdog up to date */ 64 inc_irq_stat(irq0_irqs); 65 66 /* Optimized out for !IO_APIC and x86_64 */ 67 if (timer_ack) { 68 /* 69 * Subtle, when I/O APICs are used we have to ack timer IRQ 70 * manually to deassert NMI lines for the watchdog if run 71 * on an 82489DX-based system. 72 */ 73 raw_spin_lock(&i8259A_lock); 74 outb(0x0c, PIC_MASTER_OCW3); 75 /* Ack the IRQ; AEOI will end it automatically. */ 76 inb(PIC_MASTER_POLL); 77 raw_spin_unlock(&i8259A_lock); 78 } 79 80 global_clock_event->event_handler(global_clock_event); 81 82 /* MCA bus quirk: Acknowledge irq0 by setting bit 7 in port 0x61 */ 83 if (MCA_bus) 84 outb_p(inb_p(0x61)| 0x80, 0x61); 85 86 return IRQ_HANDLED; 87} 88 89static struct irqaction irq0 = { 90 .handler = timer_interrupt, 91 .flags = IRQF_DISABLED | IRQF_NOBALANCING | IRQF_IRQPOLL | IRQF_TIMER, 92 .name = "timer" 93}; 94 95void __init setup_default_timer_irq(void) 96{ 97 setup_irq(0, &irq0); 98} 99 100/* Default timer init function */ 101void __init hpet_time_init(void) 102{ 103 if (!hpet_enable()) 104 setup_pit_timer(); 105 setup_default_timer_irq(); 106} 107 108static __init void x86_late_time_init(void) 109{ 110 x86_init.timers.timer_init(); 111 tsc_init(); 112} 113 114/* 115 * Initialize TSC and delay the periodic timer init to 116 * late x86_late_time_init() so ioremap works. 117 */ 118void __init time_init(void) 119{ 120 late_time_init = x86_late_time_init; 121} 122