linux/arch/x86/kernel/time.c
Thomas Gleixner dd0a70c8f9 x86: Move tsc_init to late_time_init
We do not need the TSC before late_time_init. Move the tsc_init to the
late time init code so we can also utilize HPET for calibration (which
we claimed to do but never did except in some older kernel
version). This also helps Moorestown to calibrate the TSC with the
AHBT timer which needs to be initialized in late_time_init like HPET.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:47 +02:00

122 lines
2.7 KiB
C

/*
* 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)
{
irq0.mask = cpumask_of_cpu(0);
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 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;
}