diff options
Diffstat (limited to 'arch/m68k/kernel/time.c')
-rw-r--r-- | arch/m68k/kernel/time.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/arch/m68k/kernel/time.c b/arch/m68k/kernel/time.c new file mode 100644 index 000000000..3857737e3 --- /dev/null +++ b/arch/m68k/kernel/time.c @@ -0,0 +1,109 @@ +/* + * 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/errno.h> +#include <linux/export.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 <linux/platform_device.h> + +#include <asm/machdep.h> +#include <asm/io.h> +#include <asm/irq_regs.h> + +#include <linux/time.h> +#include <linux/timex.h> +#include <linux/profile.h> + + +unsigned long (*mach_random_get_entropy)(void); +EXPORT_SYMBOL_GPL(mach_random_get_entropy); + + +/* + * timer_interrupt() needs to keep up the real-time clock, + * as well as call the "xtime_update()" routine every clocktick + */ +static irqreturn_t timer_interrupt(int irq, void *dummy) +{ + xtime_update(1); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); + +#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 read_persistent_clock(struct timespec *ts) +{ + struct rtc_time time; + ts->tv_sec = 0; + ts->tv_nsec = 0; + + if (mach_hwclk) { + mach_hwclk(0, &time); + + if ((time.tm_year += 1900) < 1970) + time.tm_year += 100; + ts->tv_sec = mktime(time.tm_year, time.tm_mon, time.tm_mday, + time.tm_hour, time.tm_min, time.tm_sec); + } +} + +#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET + +static int __init rtc_init(void) +{ + struct platform_device *pdev; + + if (!mach_hwclk) + return -ENODEV; + + pdev = platform_device_register_simple("rtc-generic", -1, NULL, 0); + return PTR_ERR_OR_ZERO(pdev); +} + +module_init(rtc_init); + +#endif /* CONFIG_ARCH_USES_GETTIMEOFFSET */ + +void __init time_init(void) +{ + mach_sched_init(timer_interrupt); +} |