diff options
Diffstat (limited to 'arch/sh/kernel/time.c')
| -rw-r--r-- | arch/sh/kernel/time.c | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/arch/sh/kernel/time.c b/arch/sh/kernel/time.c new file mode 100644 index 0000000..d41ca4c --- /dev/null +++ b/arch/sh/kernel/time.c @@ -0,0 +1,231 @@ +/* + * arch/sh/kernel/time_32.c + * + * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka + * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> + * Copyright (C) 2002 - 2009 Paul Mundt + * Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org> + * + * Some code taken from i386 version. + * Copyright (C) 1991, 1992, 1995 Linus Torvalds + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/profile.h> +#include <linux/timex.h> +#include <linux/sched.h> +#include <linux/clockchips.h> +#include <linux/mc146818rtc.h> /* for rtc_lock */ +#include <linux/platform_device.h> +#include <linux/smp.h> +#include <linux/rtc.h> +#include <asm/clock.h> +#include <asm/rtc.h> +#include <asm/timer.h> +#include <asm/kgdb.h> + +struct sys_timer *sys_timer; + +/* Move this somewhere more sensible.. */ +DEFINE_SPINLOCK(rtc_lock); +EXPORT_SYMBOL(rtc_lock); + +/* Dummy RTC ops */ +static void null_rtc_get_time(struct timespec *tv) +{ + tv->tv_sec = mktime(2000, 1, 1, 0, 0, 0); + tv->tv_nsec = 0; +} + +static int null_rtc_set_time(const time_t secs) +{ + return 0; +} + +void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time; +int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time; + +unsigned int get_rtc_time(struct rtc_time *tm) +{ + if (rtc_sh_get_time != null_rtc_get_time) { + struct timespec tv; + + rtc_sh_get_time(&tv); + rtc_time_to_tm(tv.tv_sec, tm); + } + + return RTC_24H; +} +EXPORT_SYMBOL(get_rtc_time); + +int set_rtc_time(struct rtc_time *tm) +{ + unsigned long secs; + + rtc_tm_to_time(tm, &secs); + return rtc_sh_set_time(secs); +} +EXPORT_SYMBOL(set_rtc_time); + +static int __init rtc_generic_init(void) +{ + struct platform_device *pdev; + + if (rtc_sh_get_time == null_rtc_get_time) + return -ENODEV; + + pdev = platform_device_register_simple("rtc-generic", -1, NULL, 0); + if (IS_ERR(pdev)) + return PTR_ERR(pdev); + + return 0; +} +module_init(rtc_generic_init); + +/* last time the RTC clock got updated */ +static long last_rtc_update; + +/* + * handle_timer_tick() needs to keep up the real-time clock, + * as well as call the "do_timer()" routine every clocktick + */ +void handle_timer_tick(void) +{ + if (current->pid) + profile_tick(CPU_PROFILING); + + /* + * 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); + do_timer(1); + + /* + * If we have an externally synchronized Linux clock, then update + * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be + * called as close as possible to 500 ms before the new second starts. + */ + if (ntp_synced() && + xtime.tv_sec > last_rtc_update + 660 && + (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 && + (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) { + if (rtc_sh_set_time(xtime.tv_sec) == 0) + last_rtc_update = xtime.tv_sec; + else + /* do it again in 60s */ + last_rtc_update = xtime.tv_sec - 600; + } + write_sequnlock(&xtime_lock); + +#ifndef CONFIG_SMP + update_process_times(user_mode(get_irq_regs())); +#endif +} + +#ifdef CONFIG_PM +int timer_suspend(struct sys_device *dev, pm_message_t state) +{ + struct sys_timer *sys_timer = container_of(dev, struct sys_timer, dev); + + sys_timer->ops->stop(); + + return 0; +} + +int timer_resume(struct sys_device *dev) +{ + struct sys_timer *sys_timer = container_of(dev, struct sys_timer, dev); + + sys_timer->ops->start(); + + return 0; +} +#else +#define timer_suspend NULL +#define timer_resume NULL +#endif + +static struct sysdev_class timer_sysclass = { + .name = "timer", + .suspend = timer_suspend, + .resume = timer_resume, +}; + +static int __init timer_init_sysfs(void) +{ + int ret; + + if (!sys_timer) + return 0; + + ret = sysdev_class_register(&timer_sysclass); + if (ret != 0) + return ret; + + sys_timer->dev.cls = &timer_sysclass; + return sysdev_register(&sys_timer->dev); +} +device_initcall(timer_init_sysfs); + +void (*board_time_init)(void); + +struct clocksource clocksource_sh = { + .name = "SuperH", +}; + +unsigned long long sched_clock(void) +{ + unsigned long long cycles; + + /* jiffies based sched_clock if no clocksource is installed */ + if (!clocksource_sh.rating) + return (unsigned long long)jiffies * (NSEC_PER_SEC / HZ); + + cycles = clocksource_sh.read(&clocksource_sh); + return cyc2ns(&clocksource_sh, cycles); +} + +static void __init sh_late_time_init(void) +{ + /* + * Make sure all compiled-in early timers register themselves. + * Run probe() for one "earlytimer" device. + */ + early_platform_driver_register_all("earlytimer"); + if (early_platform_driver_probe("earlytimer", 1, 0)) + return; + + /* + * Find the timer to use as the system timer, it will be + * initialized for us. + */ + sys_timer = get_sys_timer(); + if (unlikely(!sys_timer)) + panic("System timer missing.\n"); + + printk(KERN_INFO "Using %s for system timer\n", sys_timer->name); +} + +void __init time_init(void) +{ + if (board_time_init) + board_time_init(); + + clk_init(); + + rtc_sh_get_time(&xtime); + set_normalized_timespec(&wall_to_monotonic, + -xtime.tv_sec, -xtime.tv_nsec); + +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST + local_timer_setup(smp_processor_id()); +#endif + + late_time_init = sh_late_time_init; +} + |