/* * linux/arch/arm/kernel/time.c * * Copyright (C) 1991, 1992, 1995 Linus Torvalds * Modifications for ARM (C) 1994, 1995, 1996,1997 Russell King * Copyright (C) 1999 SuSE GmbH, (Philipp Rumpf, prumpf@tux.org) * * 1994-07-02 Alan Modra * fixed set_rtc_mmss, fixed time.year for >= 2000, new mktime * 1998-12-20 Updated NTP code according to technical memorandum Jan '96 * "A Kernel Model for Precision Timekeeping" by Dave Mills */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern rwlock_t xtime_lock; static int timer_value; static int timer_delta; static struct pdc_tod tod_data __attribute__((aligned(8))); void timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) { int old; int lost = 0; int cr16; old = timer_value; cr16 = mfctl(16); while((timer_value - cr16) < (timer_delta / 2)) { timer_value += timer_delta; lost++; } mtctl(timer_value ,16); do_timer(regs); led_interrupt_func(); } void do_gettimeofday(struct timeval *tv) { unsigned long flags; read_lock_irqsave(&xtime_lock, flags); tv->tv_sec = xtime.tv_sec; tv->tv_usec = xtime.tv_usec; read_unlock_irqrestore(&xtime_lock, flags); } void do_settimeofday(struct timeval *tv) { write_lock_irq(&xtime_lock); xtime.tv_sec = tv->tv_sec; xtime.tv_usec = tv->tv_usec; write_unlock_irq(&xtime_lock); } void __init time_init(void) { timer_delta = (100 * PAGE0->mem_10msec) / HZ; /* make the first timer interrupt go off in one second */ timer_value = mfctl(16) + (HZ * timer_delta); mtctl(timer_value, 16); if(pdc_tod_read(&tod_data) == 0) { xtime.tv_sec = tod_data.tod_sec; xtime.tv_usec = tod_data.tod_usec; } else { printk(KERN_ERR "Error reading tod clock\n"); xtime.tv_sec = 0; xtime.tv_usec = 0; } }