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-rw-r--r--arch/i386/kernel/time.c485
1 files changed, 0 insertions, 485 deletions
diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c
deleted file mode 100644
index 41c5b2dc620..00000000000
--- a/arch/i386/kernel/time.c
+++ /dev/null
@@ -1,485 +0,0 @@
-/*
- * linux/arch/i386/kernel/time.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/errno.h>
-#include <linux/sched.h>
-#include <linux/kernel.h>
-#include <linux/param.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/interrupt.h>
-#include <linux/time.h>
-#include <linux/delay.h>
-#include <linux/init.h>
-#include <linux/smp.h>
-#include <linux/module.h>
-#include <linux/sysdev.h>
-#include <linux/bcd.h>
-#include <linux/efi.h>
-#include <linux/mca.h>
-
-#include <asm/io.h>
-#include <asm/smp.h>
-#include <asm/irq.h>
-#include <asm/msr.h>
-#include <asm/delay.h>
-#include <asm/mpspec.h>
-#include <asm/uaccess.h>
-#include <asm/processor.h>
-#include <asm/timer.h>
-
-#include "mach_time.h"
-
-#include <linux/timex.h>
-#include <linux/config.h>
-
-#include <asm/hpet.h>
-
-#include <asm/arch_hooks.h>
-
-#include "io_ports.h"
-
-#include <asm/i8259.h>
-
-int pit_latch_buggy; /* extern */
-
-#include "do_timer.h"
-
-unsigned int cpu_khz; /* Detected as we calibrate the TSC */
-EXPORT_SYMBOL(cpu_khz);
-
-extern unsigned long wall_jiffies;
-
-DEFINE_SPINLOCK(rtc_lock);
-EXPORT_SYMBOL(rtc_lock);
-
-#include <asm/i8253.h>
-
-DEFINE_SPINLOCK(i8253_lock);
-EXPORT_SYMBOL(i8253_lock);
-
-struct timer_opts *cur_timer __read_mostly = &timer_none;
-
-/*
- * This is a special lock that is owned by the CPU and holds the index
- * register we are working with. It is required for NMI access to the
- * CMOS/RTC registers. See include/asm-i386/mc146818rtc.h for details.
- */
-volatile unsigned long cmos_lock = 0;
-EXPORT_SYMBOL(cmos_lock);
-
-/* Routines for accessing the CMOS RAM/RTC. */
-unsigned char rtc_cmos_read(unsigned char addr)
-{
- unsigned char val;
- lock_cmos_prefix(addr);
- outb_p(addr, RTC_PORT(0));
- val = inb_p(RTC_PORT(1));
- lock_cmos_suffix(addr);
- return val;
-}
-EXPORT_SYMBOL(rtc_cmos_read);
-
-void rtc_cmos_write(unsigned char val, unsigned char addr)
-{
- lock_cmos_prefix(addr);
- outb_p(addr, RTC_PORT(0));
- outb_p(val, RTC_PORT(1));
- lock_cmos_suffix(addr);
-}
-EXPORT_SYMBOL(rtc_cmos_write);
-
-/*
- * This version of gettimeofday has microsecond resolution
- * and better than microsecond precision on fast x86 machines with TSC.
- */
-void do_gettimeofday(struct timeval *tv)
-{
- unsigned long seq;
- unsigned long usec, sec;
- unsigned long max_ntp_tick;
-
- do {
- unsigned long lost;
-
- seq = read_seqbegin(&xtime_lock);
-
- usec = cur_timer->get_offset();
- lost = jiffies - wall_jiffies;
-
- /*
- * If time_adjust is negative then NTP is slowing the clock
- * so make sure not to go into next possible interval.
- * Better to lose some accuracy than have time go backwards..
- */
- if (unlikely(time_adjust < 0)) {
- max_ntp_tick = (USEC_PER_SEC / HZ) - tickadj;
- usec = min(usec, max_ntp_tick);
-
- if (lost)
- usec += lost * max_ntp_tick;
- }
- else if (unlikely(lost))
- usec += lost * (USEC_PER_SEC / HZ);
-
- sec = xtime.tv_sec;
- usec += (xtime.tv_nsec / 1000);
- } while (read_seqretry(&xtime_lock, seq));
-
- while (usec >= 1000000) {
- usec -= 1000000;
- sec++;
- }
-
- tv->tv_sec = sec;
- tv->tv_usec = usec;
-}
-
-EXPORT_SYMBOL(do_gettimeofday);
-
-int do_settimeofday(struct timespec *tv)
-{
- time_t wtm_sec, sec = tv->tv_sec;
- long wtm_nsec, nsec = tv->tv_nsec;
-
- if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
- return -EINVAL;
-
- write_seqlock_irq(&xtime_lock);
- /*
- * This is revolting. We need to set "xtime" correctly. However, the
- * value in this location is the value at the most recent update of
- * wall time. Discover what correction gettimeofday() would have
- * made, and then undo it!
- */
- nsec -= cur_timer->get_offset() * NSEC_PER_USEC;
- nsec -= (jiffies - wall_jiffies) * TICK_NSEC;
-
- wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
- wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
-
- set_normalized_timespec(&xtime, sec, nsec);
- set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
-
- ntp_clear();
- write_sequnlock_irq(&xtime_lock);
- clock_was_set();
- return 0;
-}
-
-EXPORT_SYMBOL(do_settimeofday);
-
-static int set_rtc_mmss(unsigned long nowtime)
-{
- int retval;
-
- WARN_ON(irqs_disabled());
-
- /* gets recalled with irq locally disabled */
- spin_lock_irq(&rtc_lock);
- if (efi_enabled)
- retval = efi_set_rtc_mmss(nowtime);
- else
- retval = mach_set_rtc_mmss(nowtime);
- spin_unlock_irq(&rtc_lock);
-
- return retval;
-}
-
-
-int timer_ack;
-
-/* monotonic_clock(): returns # of nanoseconds passed since time_init()
- * Note: This function is required to return accurate
- * time even in the absence of multiple timer ticks.
- */
-unsigned long long monotonic_clock(void)
-{
- return cur_timer->monotonic_clock();
-}
-EXPORT_SYMBOL(monotonic_clock);
-
-#if defined(CONFIG_SMP) && defined(CONFIG_FRAME_POINTER)
-unsigned long profile_pc(struct pt_regs *regs)
-{
- unsigned long pc = instruction_pointer(regs);
-
- if (in_lock_functions(pc))
- return *(unsigned long *)(regs->ebp + 4);
-
- return pc;
-}
-EXPORT_SYMBOL(profile_pc);
-#endif
-
-/*
- * timer_interrupt() needs to keep up the real-time clock,
- * as well as call the "do_timer()" routine every clocktick
- */
-static inline void do_timer_interrupt(int irq, struct pt_regs *regs)
-{
-#ifdef CONFIG_X86_IO_APIC
- if (timer_ack) {
- /*
- * Subtle, when I/O APICs are used we have to ack timer IRQ
- * manually to reset the IRR bit for do_slow_gettimeoffset().
- * This will also 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(regs);
-
-
- 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. */
-
- irq = inb_p( 0x61 ); /* read the current state */
- outb_p( irq|0x80, 0x61 ); /* reset the IRQ */
- }
-}
-
-/*
- * 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, struct pt_regs *regs)
-{
- /*
- * Here we are in the timer irq handler. We just have irqs locally
- * disabled but we don't know if the timer_bh is running on the other
- * CPU. We need to avoid to SMP race with it. NOTE: we don' t need
- * the irq version of write_lock because as just said we have irq
- * locally disabled. -arca
- */
- write_seqlock(&xtime_lock);
-
- cur_timer->mark_offset();
-
- do_timer_interrupt(irq, regs);
-
- write_sequnlock(&xtime_lock);
- return IRQ_HANDLED;
-}
-
-/* not static: needed by APM */
-unsigned long get_cmos_time(void)
-{
- unsigned long retval;
-
- spin_lock(&rtc_lock);
-
- if (efi_enabled)
- retval = efi_get_time();
- else
- retval = mach_get_cmos_time();
-
- spin_unlock(&rtc_lock);
-
- return retval;
-}
-EXPORT_SYMBOL(get_cmos_time);
-
-static void sync_cmos_clock(unsigned long dummy);
-
-static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
-
-static void sync_cmos_clock(unsigned long dummy)
-{
- struct timeval now, next;
- int fail = 1;
-
- /*
- * If we have an externally synchronized Linux clock, then update
- * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
- * called as close as possible to 500 ms before the new second starts.
- * This code is run on a timer. If the clock is set, that timer
- * may not expire at the correct time. Thus, we adjust...
- */
- if (!ntp_synced())
- /*
- * Not synced, exit, do not restart a timer (if one is
- * running, let it run out).
- */
- return;
-
- do_gettimeofday(&now);
- if (now.tv_usec >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
- now.tv_usec <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2)
- fail = set_rtc_mmss(now.tv_sec);
-
- next.tv_usec = USEC_AFTER - now.tv_usec;
- if (next.tv_usec <= 0)
- next.tv_usec += USEC_PER_SEC;
-
- if (!fail)
- next.tv_sec = 659;
- else
- next.tv_sec = 0;
-
- if (next.tv_usec >= USEC_PER_SEC) {
- next.tv_sec++;
- next.tv_usec -= USEC_PER_SEC;
- }
- mod_timer(&sync_cmos_timer, jiffies + timeval_to_jiffies(&next));
-}
-
-void notify_arch_cmos_timer(void)
-{
- mod_timer(&sync_cmos_timer, jiffies + 1);
-}
-
-static long clock_cmos_diff, sleep_start;
-
-static struct timer_opts *last_timer;
-static int timer_suspend(struct sys_device *dev, pm_message_t state)
-{
- /*
- * Estimate time zone so that set_time can update the clock
- */
- clock_cmos_diff = -get_cmos_time();
- clock_cmos_diff += get_seconds();
- sleep_start = get_cmos_time();
- last_timer = cur_timer;
- cur_timer = &timer_none;
- if (last_timer->suspend)
- last_timer->suspend(state);
- return 0;
-}
-
-static int timer_resume(struct sys_device *dev)
-{
- unsigned long flags;
- unsigned long sec;
- unsigned long sleep_length;
-
-#ifdef CONFIG_HPET_TIMER
- if (is_hpet_enabled())
- hpet_reenable();
-#endif
- setup_pit_timer();
- sec = get_cmos_time() + clock_cmos_diff;
- sleep_length = (get_cmos_time() - sleep_start) * HZ;
- write_seqlock_irqsave(&xtime_lock, flags);
- xtime.tv_sec = sec;
- xtime.tv_nsec = 0;
- write_sequnlock_irqrestore(&xtime_lock, flags);
- jiffies += sleep_length;
- wall_jiffies += sleep_length;
- if (last_timer->resume)
- last_timer->resume();
- cur_timer = last_timer;
- last_timer = NULL;
- touch_softlockup_watchdog();
- return 0;
-}
-
-static struct sysdev_class timer_sysclass = {
- .resume = timer_resume,
- .suspend = timer_suspend,
- set_kset_name("timer"),
-};
-
-
-/* XXX this driverfs stuff should probably go elsewhere later -john */
-static struct sys_device device_timer = {
- .id = 0,
- .cls = &timer_sysclass,
-};
-
-static int time_init_device(void)
-{
- int error = sysdev_class_register(&timer_sysclass);
- if (!error)
- error = sysdev_register(&device_timer);
- return error;
-}
-
-device_initcall(time_init_device);
-
-#ifdef CONFIG_HPET_TIMER
-extern void (*late_time_init)(void);
-/* Duplicate of time_init() below, with hpet_enable part added */
-static void __init hpet_time_init(void)
-{
- xtime.tv_sec = get_cmos_time();
- xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
- set_normalized_timespec(&wall_to_monotonic,
- -xtime.tv_sec, -xtime.tv_nsec);
-
- if ((hpet_enable() >= 0) && hpet_use_timer) {
- printk("Using HPET for base-timer\n");
- }
-
- cur_timer = select_timer();
- printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name);
-
- time_init_hook();
-}
-#endif
-
-void __init time_init(void)
-{
-#ifdef CONFIG_HPET_TIMER
- if (is_hpet_capable()) {
- /*
- * HPET initialization needs to do memory-mapped io. So, let
- * us do a late initialization after mem_init().
- */
- late_time_init = hpet_time_init;
- return;
- }
-#endif
- xtime.tv_sec = get_cmos_time();
- xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
- set_normalized_timespec(&wall_to_monotonic,
- -xtime.tv_sec, -xtime.tv_nsec);
-
- cur_timer = select_timer();
- printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name);
-
- time_init_hook();
-}
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