diff options
Diffstat (limited to 'arch/x86/kernel/time.c')
-rw-r--r-- | arch/x86/kernel/time.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c new file mode 100644 index 0000000..dcb00d2 --- /dev/null +++ b/arch/x86/kernel/time.c @@ -0,0 +1,120 @@ +/* + * Copyright (c) 1991,1992,1995 Linus Torvalds + * Copyright (c) 1994 Alan Modra + * Copyright (c) 1995 Markus Kuhn + * Copyright (c) 1996 Ingo Molnar + * Copyright (c) 1998 Andrea Arcangeli + * Copyright (c) 2002,2006 Vojtech Pavlik + * Copyright (c) 2003 Andi Kleen + * + */ + +#include <linux/clockchips.h> +#include <linux/interrupt.h> +#include <linux/time.h> +#include <linux/mca.h> + +#include <asm/vsyscall.h> +#include <asm/x86_init.h> +#include <asm/i8259.h> +#include <asm/i8253.h> +#include <asm/timer.h> +#include <asm/hpet.h> +#include <asm/time.h> + +#if defined(CONFIG_X86_32) && defined(CONFIG_X86_IO_APIC) +int timer_ack; +#endif + +#ifdef CONFIG_X86_64 +volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES; +#endif + +unsigned long profile_pc(struct pt_regs *regs) +{ + unsigned long pc = instruction_pointer(regs); + + if (!user_mode_vm(regs) && in_lock_functions(pc)) { +#ifdef CONFIG_FRAME_POINTER + return *(unsigned long *)(regs->bp + sizeof(long)); +#else + unsigned long *sp = (unsigned long *)regs->sp; + /* + * Return address is either directly at stack pointer + * or above a saved flags. Eflags has bits 22-31 zero, + * kernel addresses don't. + */ + if (sp[0] >> 22) + return sp[0]; + if (sp[1] >> 22) + return sp[1]; +#endif + } + return pc; +} +EXPORT_SYMBOL(profile_pc); + +/* + * Default timer interrupt handler for PIT/HPET + */ +static irqreturn_t timer_interrupt(int irq, void *dev_id) +{ + /* Keep nmi watchdog up to date */ + inc_irq_stat(irq0_irqs); + + /* Optimized out for !IO_APIC and x86_64 */ + if (timer_ack) { + /* + * Subtle, when I/O APICs are used we have to ack timer IRQ + * manually to deassert NMI lines for the watchdog if run + * on an 82489DX-based system. + */ + spin_lock(&i8259A_lock); + outb(0x0c, PIC_MASTER_OCW3); + /* Ack the IRQ; AEOI will end it automatically. */ + inb(PIC_MASTER_POLL); + spin_unlock(&i8259A_lock); + } + + global_clock_event->event_handler(global_clock_event); + + /* MCA bus quirk: Acknowledge irq0 by setting bit 7 in port 0x61 */ + if (MCA_bus) + outb_p(inb_p(0x61)| 0x80, 0x61); + + return IRQ_HANDLED; +} + +static struct irqaction irq0 = { + .handler = timer_interrupt, + .flags = IRQF_DISABLED | IRQF_NOBALANCING | IRQF_IRQPOLL | IRQF_TIMER, + .name = "timer" +}; + +void __init setup_default_timer_irq(void) +{ + setup_irq(0, &irq0); +} + +/* Default timer init function */ +void __init hpet_time_init(void) +{ + if (!hpet_enable()) + setup_pit_timer(); + setup_default_timer_irq(); +} + +static __init void x86_late_time_init(void) +{ + x86_init.timers.timer_init(); + tsc_init(); +} + +/* + * Initialize TSC and delay the periodic timer init to + * late x86_late_time_init() so ioremap works. + */ +void __init time_init(void) +{ + late_time_init = x86_late_time_init; +} |