From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001
From: Linus Torvalds <torvalds@ppc970.osdl.org>
Date: Sat, 16 Apr 2005 15:20:36 -0700
Subject: Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
---
 arch/m68k/kernel/time.c | 187 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 187 insertions(+)
 create mode 100644 arch/m68k/kernel/time.c

(limited to 'arch/m68k/kernel/time.c')

diff --git a/arch/m68k/kernel/time.c b/arch/m68k/kernel/time.c
new file mode 100644
index 00000000000..e47e1958852
--- /dev/null
+++ b/arch/m68k/kernel/time.c
@@ -0,0 +1,187 @@
+/*
+ *  linux/arch/m68k/kernel/time.c
+ *
+ *  Copyright (C) 1991, 1992, 1995  Linus Torvalds
+ *
+ * This file contains the m68k-specific time handling details.
+ * Most of the stuff is located in the machine specific files.
+ *
+ * 1997-09-10	Updated NTP code according to technical memorandum Jan '96
+ *		"A Kernel Model for Precision Timekeeping" by Dave Mills
+ */
+
+#include <linux/config.h> /* CONFIG_HEARTBEAT */
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/param.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/rtc.h>
+
+#include <asm/machdep.h>
+#include <asm/io.h>
+
+#include <linux/time.h>
+#include <linux/timex.h>
+#include <linux/profile.h>
+
+u64 jiffies_64 = INITIAL_JIFFIES;
+
+EXPORT_SYMBOL(jiffies_64);
+
+static inline int set_rtc_mmss(unsigned long nowtime)
+{
+  if (mach_set_clock_mmss)
+    return mach_set_clock_mmss (nowtime);
+  return -1;
+}
+
+/*
+ * timer_interrupt() needs to keep up the real-time clock,
+ * as well as call the "do_timer()" routine every clocktick
+ */
+static irqreturn_t timer_interrupt(int irq, void *dummy, struct pt_regs * regs)
+{
+	do_timer(regs);
+#ifndef CONFIG_SMP
+	update_process_times(user_mode(regs));
+#endif
+	profile_tick(CPU_PROFILING, regs);
+
+#ifdef CONFIG_HEARTBEAT
+	/* use power LED as a heartbeat instead -- much more useful
+	   for debugging -- based on the version for PReP by Cort */
+	/* acts like an actual heart beat -- ie thump-thump-pause... */
+	if (mach_heartbeat) {
+	    static unsigned cnt = 0, period = 0, dist = 0;
+
+	    if (cnt == 0 || cnt == dist)
+		mach_heartbeat( 1 );
+	    else if (cnt == 7 || cnt == dist+7)
+		mach_heartbeat( 0 );
+
+	    if (++cnt > period) {
+		cnt = 0;
+		/* The hyperbolic function below modifies the heartbeat period
+		 * length in dependency of the current (5min) load. It goes
+		 * through the points f(0)=126, f(1)=86, f(5)=51,
+		 * f(inf)->30. */
+		period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) + 30;
+		dist = period / 4;
+	    }
+	}
+#endif /* CONFIG_HEARTBEAT */
+	return IRQ_HANDLED;
+}
+
+void time_init(void)
+{
+	struct rtc_time time;
+
+	if (mach_hwclk) {
+		mach_hwclk(0, &time);
+
+		if ((time.tm_year += 1900) < 1970)
+			time.tm_year += 100;
+		xtime.tv_sec = mktime(time.tm_year, time.tm_mon, time.tm_mday,
+				      time.tm_hour, time.tm_min, time.tm_sec);
+		xtime.tv_nsec = 0;
+	}
+	wall_to_monotonic.tv_sec = -xtime.tv_sec;
+
+	mach_sched_init(timer_interrupt);
+}
+
+/*
+ * This version of gettimeofday has near microsecond resolution.
+ */
+void do_gettimeofday(struct timeval *tv)
+{
+	unsigned long flags;
+	extern unsigned long wall_jiffies;
+	unsigned long seq;
+	unsigned long usec, sec, lost;
+	unsigned long max_ntp_tick = tick_usec - tickadj;
+
+	do {
+		seq = read_seqbegin_irqsave(&xtime_lock, flags);
+
+		usec = mach_gettimeoffset();
+		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)) {
+			usec = min(usec, max_ntp_tick);
+
+			if (lost)
+				usec += lost * max_ntp_tick;
+		}
+		else if (unlikely(lost))
+			usec += lost * tick_usec;
+
+		sec = xtime.tv_sec;
+		usec += xtime.tv_nsec/1000;
+	} while (read_seqretry_irqrestore(&xtime_lock, seq, flags));
+
+
+	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;
+	extern unsigned long wall_jiffies;
+
+	if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
+		return -EINVAL;
+
+	write_seqlock_irq(&xtime_lock);
+	/* This is revolting. We need to set the xtime.tv_nsec
+	 * correctly. However, the value in this location is
+	 * is value at the last tick.
+	 * Discover what correction gettimeofday
+	 * would have done, and then undo it!
+	 */
+	nsec -= 1000 * (mach_gettimeoffset() +
+			(jiffies - wall_jiffies) * (1000000 / HZ));
+
+	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);
+
+	time_adjust = 0;		/* stop active adjtime() */
+	time_status |= STA_UNSYNC;
+	time_maxerror = NTP_PHASE_LIMIT;
+	time_esterror = NTP_PHASE_LIMIT;
+	write_sequnlock_irq(&xtime_lock);
+	clock_was_set();
+	return 0;
+}
+
+EXPORT_SYMBOL(do_settimeofday);
+
+/*
+ * Scheduler clock - returns current time in ns units.
+ */
+unsigned long long sched_clock(void)
+{
+       return (unsigned long long)jiffies*(1000000000/HZ);
+}
+
-- 
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