2 * linux/arch/m68k/kernel/time.c
4 * Copyright (C) 1991, 1992, 1995 Linus Torvalds
6 * This file contains the m68k-specific time handling details.
7 * Most of the stuff is located in the machine specific files.
9 * 1997-09-10 Updated NTP code according to technical memorandum Jan '96
10 * "A Kernel Model for Precision Timekeeping" by Dave Mills
13 #include <linux/errno.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
17 #include <linux/param.h>
18 #include <linux/string.h>
20 #include <linux/rtc.h>
21 #include <linux/platform_device.h>
23 #include <asm/machdep.h>
25 #include <asm/irq_regs.h>
27 #include <linux/time.h>
28 #include <linux/timex.h>
29 #include <linux/profile.h>
31 static inline int set_rtc_mmss(unsigned long nowtime)
33 if (mach_set_clock_mmss)
34 return mach_set_clock_mmss (nowtime);
39 * timer_interrupt() needs to keep up the real-time clock,
40 * as well as call the "do_timer()" routine every clocktick
42 static irqreturn_t timer_interrupt(int irq, void *dummy)
46 update_process_times(user_mode(get_irq_regs()));
48 profile_tick(CPU_PROFILING);
50 #ifdef CONFIG_HEARTBEAT
51 /* use power LED as a heartbeat instead -- much more useful
52 for debugging -- based on the version for PReP by Cort */
53 /* acts like an actual heart beat -- ie thump-thump-pause... */
55 static unsigned cnt = 0, period = 0, dist = 0;
57 if (cnt == 0 || cnt == dist)
59 else if (cnt == 7 || cnt == dist+7)
64 /* The hyperbolic function below modifies the heartbeat period
65 * length in dependency of the current (5min) load. It goes
66 * through the points f(0)=126, f(1)=86, f(5)=51,
68 period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) + 30;
72 #endif /* CONFIG_HEARTBEAT */
76 void read_persistent_clock(struct timespec *ts)
85 if ((time.tm_year += 1900) < 1970)
87 ts->tv_sec = mktime(time.tm_year, time.tm_mon, time.tm_mday,
88 time.tm_hour, time.tm_min, time.tm_sec);
92 void __init time_init(void)
94 mach_sched_init(timer_interrupt);
97 u32 arch_gettimeoffset(void)
99 return mach_gettimeoffset() * 1000;
102 static int __init rtc_init(void)
104 struct platform_device *pdev;
109 pdev = platform_device_register_simple("rtc-generic", -1, NULL, 0);
111 return PTR_ERR(pdev);
116 module_init(rtc_init);