linux_old1/arch/x86/kernel/time.c

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/*
* 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 */
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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();
}
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/*
* Initialize TSC and delay the periodic timer init to
* late x86_late_time_init() so ioremap works.
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*/
void __init time_init(void)
{
[PATCH] clocksource init adjustments (fix bug #7426) This patch resolves the issue found here: http://bugme.osdl.org/show_bug.cgi?id=7426 The basic summary is: Currently we register most of i386/x86_64 clocksources at module_init time. Then we enable clocksource selection at late_initcall time. This causes some problems for drivers that use gettimeofday for init calibration routines (specifically the es1968 driver in this case), where durring module_init, the only clocksource available is the low-res jiffies clocksource. This may cause slight calibration errors, due to the small sampling time used. It should be noted that drivers that require fine grained time may not function on architectures that do not have better then jiffies resolution timekeeping (there are a few). However, this does not discount the reasonable need for such fine-grained timekeeping at init time. Thus the solution here is to register clocksources earlier (ideally when the hardware is being initialized), and then we enable clocksource selection at fs_initcall (before device_initcall). This patch should probably get some testing time in -mm, since clocksource selection is one of the most important issues for correct timekeeping, and I've only been able to test this on a few of my own boxes. Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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tsc_init();
late_time_init = x86_late_time_init;
}