/* * arch/sh/kernel/time_32.c * * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka * Copyright (C) 2000 Philipp Rumpf * Copyright (C) 2002 - 2008 Paul Mundt * Copyright (C) 2002 M. R. Brown * * Some code taken from i386 version. * Copyright (C) 1991, 1992, 1995 Linus Torvalds */ #include #include #include #include #include #include #include #include /* for rtc_lock */ #include #include #include #include #include #include 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; #ifndef CONFIG_GENERIC_TIME void do_gettimeofday(struct timeval *tv) { unsigned long flags; unsigned long seq; unsigned long usec, sec; do { /* * Turn off IRQs when grabbing xtime_lock, so that * the sys_timer get_offset code doesn't have to handle it. */ seq = read_seqbegin_irqsave(&xtime_lock, flags); usec = get_timer_offset(); sec = xtime.tv_sec; usec += xtime.tv_nsec / NSEC_PER_USEC; } 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; if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) return -EINVAL; write_seqlock_irq(&xtime_lock); /* * This is revolting. We need to set "xtime" correctly. However, the * value in this location is the value at the most recent update of * wall time. Discover what correction gettimeofday() would have * made, and then undo it! */ nsec -= get_timer_offset() * NSEC_PER_USEC; 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); ntp_clear(); write_sequnlock_irq(&xtime_lock); clock_was_set(); return 0; } EXPORT_SYMBOL(do_settimeofday); #endif /* !CONFIG_GENERIC_TIME */ /* 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", }; #ifdef CONFIG_GENERIC_TIME 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(); return cyc2ns(&clocksource_sh, cycles); } #endif 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 /* * 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); }