108 lines
2.5 KiB
C
108 lines
2.5 KiB
C
/*
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* linux/arch/m68k/kernel/time.c
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*
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* Copyright (C) 1991, 1992, 1995 Linus Torvalds
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*
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* This file contains the m68k-specific time handling details.
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* Most of the stuff is located in the machine specific files.
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*
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* 1997-09-10 Updated NTP code according to technical memorandum Jan '96
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* "A Kernel Model for Precision Timekeeping" by Dave Mills
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*/
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#include <linux/errno.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/kernel.h>
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#include <linux/param.h>
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#include <linux/string.h>
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#include <linux/mm.h>
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#include <linux/rtc.h>
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#include <linux/platform_device.h>
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#include <asm/machdep.h>
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#include <asm/io.h>
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#include <asm/irq_regs.h>
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#include <linux/time.h>
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#include <linux/timex.h>
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#include <linux/profile.h>
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unsigned long (*mach_random_get_entropy)(void);
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/*
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* timer_interrupt() needs to keep up the real-time clock,
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* as well as call the "xtime_update()" routine every clocktick
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*/
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static irqreturn_t timer_interrupt(int irq, void *dummy)
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{
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xtime_update(1);
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update_process_times(user_mode(get_irq_regs()));
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profile_tick(CPU_PROFILING);
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#ifdef CONFIG_HEARTBEAT
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/* use power LED as a heartbeat instead -- much more useful
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for debugging -- based on the version for PReP by Cort */
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/* acts like an actual heart beat -- ie thump-thump-pause... */
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if (mach_heartbeat) {
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static unsigned cnt = 0, period = 0, dist = 0;
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if (cnt == 0 || cnt == dist)
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mach_heartbeat( 1 );
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else if (cnt == 7 || cnt == dist+7)
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mach_heartbeat( 0 );
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if (++cnt > period) {
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cnt = 0;
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/* The hyperbolic function below modifies the heartbeat period
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* length in dependency of the current (5min) load. It goes
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* through the points f(0)=126, f(1)=86, f(5)=51,
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* f(inf)->30. */
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period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) + 30;
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dist = period / 4;
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}
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}
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#endif /* CONFIG_HEARTBEAT */
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return IRQ_HANDLED;
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}
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void read_persistent_clock(struct timespec *ts)
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{
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struct rtc_time time;
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ts->tv_sec = 0;
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ts->tv_nsec = 0;
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if (mach_hwclk) {
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mach_hwclk(0, &time);
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if ((time.tm_year += 1900) < 1970)
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time.tm_year += 100;
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ts->tv_sec = mktime(time.tm_year, time.tm_mon, time.tm_mday,
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time.tm_hour, time.tm_min, time.tm_sec);
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}
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}
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#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
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static int __init rtc_init(void)
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{
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struct platform_device *pdev;
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if (!mach_hwclk)
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return -ENODEV;
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pdev = platform_device_register_simple("rtc-generic", -1, NULL, 0);
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return PTR_ERR_OR_ZERO(pdev);
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}
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module_init(rtc_init);
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#endif /* CONFIG_ARCH_USES_GETTIMEOFFSET */
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void __init time_init(void)
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{
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mach_sched_init(timer_interrupt);
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}
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