mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-16 08:44:21 +08:00
8ae9366909
Impact: cleanup Replace incrementing irq stat with inc_irq_stat() in non-unified functions. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
138 lines
4.1 KiB
C
138 lines
4.1 KiB
C
/*
|
|
* Copyright (C) 1991, 1992, 1995 Linus Torvalds
|
|
*
|
|
* This file contains the PC-specific time handling details:
|
|
* reading the RTC at bootup, etc..
|
|
* 1994-07-02 Alan Modra
|
|
* fixed set_rtc_mmss, fixed time.year for >= 2000, new mktime
|
|
* 1995-03-26 Markus Kuhn
|
|
* fixed 500 ms bug at call to set_rtc_mmss, fixed DS12887
|
|
* precision CMOS clock update
|
|
* 1996-05-03 Ingo Molnar
|
|
* fixed time warps in do_[slow|fast]_gettimeoffset()
|
|
* 1997-09-10 Updated NTP code according to technical memorandum Jan '96
|
|
* "A Kernel Model for Precision Timekeeping" by Dave Mills
|
|
* 1998-09-05 (Various)
|
|
* More robust do_fast_gettimeoffset() algorithm implemented
|
|
* (works with APM, Cyrix 6x86MX and Centaur C6),
|
|
* monotonic gettimeofday() with fast_get_timeoffset(),
|
|
* drift-proof precision TSC calibration on boot
|
|
* (C. Scott Ananian <cananian@alumni.princeton.edu>, Andrew D.
|
|
* Balsa <andrebalsa@altern.org>, Philip Gladstone <philip@raptor.com>;
|
|
* ported from 2.0.35 Jumbo-9 by Michael Krause <m.krause@tu-harburg.de>).
|
|
* 1998-12-16 Andrea Arcangeli
|
|
* Fixed Jumbo-9 code in 2.1.131: do_gettimeofday was missing 1 jiffy
|
|
* because was not accounting lost_ticks.
|
|
* 1998-12-24 Copyright (C) 1998 Andrea Arcangeli
|
|
* Fixed a xtime SMP race (we need the xtime_lock rw spinlock to
|
|
* serialize accesses to xtime/lost_ticks).
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/time.h>
|
|
#include <linux/mca.h>
|
|
|
|
#include <asm/arch_hooks.h>
|
|
#include <asm/hpet.h>
|
|
#include <asm/time.h>
|
|
#include <asm/timer.h>
|
|
|
|
#include "do_timer.h"
|
|
|
|
int timer_ack;
|
|
|
|
unsigned long profile_pc(struct pt_regs *regs)
|
|
{
|
|
unsigned long pc = instruction_pointer(regs);
|
|
|
|
#ifdef CONFIG_SMP
|
|
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 *)®s->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
|
|
}
|
|
#endif
|
|
return pc;
|
|
}
|
|
EXPORT_SYMBOL(profile_pc);
|
|
|
|
/*
|
|
* This is the same as the above, except we _also_ save the current
|
|
* Time Stamp Counter value at the time of the timer interrupt, so that
|
|
* we later on can estimate the time of day more exactly.
|
|
*/
|
|
irqreturn_t timer_interrupt(int irq, void *dev_id)
|
|
{
|
|
/* Keep nmi watchdog up to date */
|
|
inc_irq_stat(irq0_irqs);
|
|
|
|
#ifdef CONFIG_X86_IO_APIC
|
|
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);
|
|
}
|
|
#endif
|
|
|
|
do_timer_interrupt_hook();
|
|
|
|
#ifdef CONFIG_MCA
|
|
if (MCA_bus) {
|
|
/* The PS/2 uses level-triggered interrupts. You can't
|
|
turn them off, nor would you want to (any attempt to
|
|
enable edge-triggered interrupts usually gets intercepted by a
|
|
special hardware circuit). Hence we have to acknowledge
|
|
the timer interrupt. Through some incredibly stupid
|
|
design idea, the reset for IRQ 0 is done by setting the
|
|
high bit of the PPI port B (0x61). Note that some PS/2s,
|
|
notably the 55SX, work fine if this is removed. */
|
|
|
|
u8 irq_v = inb_p( 0x61 ); /* read the current state */
|
|
outb_p( irq_v|0x80, 0x61 ); /* reset the IRQ */
|
|
}
|
|
#endif
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/* Duplicate of time_init() below, with hpet_enable part added */
|
|
void __init hpet_time_init(void)
|
|
{
|
|
if (!hpet_enable())
|
|
setup_pit_timer();
|
|
time_init_hook();
|
|
}
|
|
|
|
/*
|
|
* This is called directly from init code; we must delay timer setup in the
|
|
* HPET case as we can't make the decision to turn on HPET this early in the
|
|
* boot process.
|
|
*
|
|
* The chosen time_init function will usually be hpet_time_init, above, but
|
|
* in the case of virtual hardware, an alternative function may be substituted.
|
|
*/
|
|
void __init time_init(void)
|
|
{
|
|
pre_time_init_hook();
|
|
tsc_init();
|
|
late_time_init = choose_time_init();
|
|
}
|