From 4f543fa41e78bd366123424a3378f2f4918c0f33 Mon Sep 17 00:00:00 2001 From: john stultz Date: Mon, 21 Sep 2009 17:04:00 -0700 Subject: alpha: convert to use arch_gettimeoffset() Converts alpha to use GENERIC_TIME via the arch_getoffset() infrastructure, reducing the amount of arch specific code we need to maintain. I suspect the alpha arch could even be further improved to provide and rpcc() based clocksource, but not having the hardware, I don't feel comfortable attempting the more complicated conversion (but I'd be glad to help if anyone else is interested). [akpm@linux-foundation.org: fix build] Signed-off-by: John Stultz Cc: Richard Henderson Cc: Ivan Kokshaysky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/alpha/kernel/time.c | 79 +++++------------------------------------------- 1 file changed, 7 insertions(+), 72 deletions(-) (limited to 'arch/alpha/kernel/time.c') diff --git a/arch/alpha/kernel/time.c b/arch/alpha/kernel/time.c index b04e2cbf23a4..5d0826654c61 100644 --- a/arch/alpha/kernel/time.c +++ b/arch/alpha/kernel/time.c @@ -408,28 +408,17 @@ time_init(void) * part. So we can't do the "find absolute time in terms of cycles" thing * that the other ports do. */ -void -do_gettimeofday(struct timeval *tv) +u32 arch_gettimeoffset(void) { - unsigned long flags; - unsigned long sec, usec, seq; - unsigned long delta_cycles, delta_usec, partial_tick; - - do { - seq = read_seqbegin_irqsave(&xtime_lock, flags); - - delta_cycles = rpcc() - state.last_time; - sec = xtime.tv_sec; - usec = (xtime.tv_nsec / 1000); - partial_tick = state.partial_tick; - - } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); - #ifdef CONFIG_SMP /* Until and unless we figure out how to get cpu cycle counters in sync and keep them there, we can't use the rpcc tricks. */ - delta_usec = 0; + return 0; #else + unsigned long delta_cycles, delta_usec, partial_tick; + + delta_cycles = rpcc() - state.last_time; + partial_tick = state.partial_tick; /* * usec = cycles * ticks_per_cycle * 2**48 * 1e6 / (2**48 * ticks) * = cycles * (s_t_p_c) * 1e6 / (2**48 * ticks) @@ -446,64 +435,10 @@ do_gettimeofday(struct timeval *tv) delta_usec = (delta_cycles * state.scaled_ticks_per_cycle + partial_tick) * 15625; delta_usec = ((delta_usec / ((1UL << (FIX_SHIFT-6-1)) * HZ)) + 1) / 2; + return delta_usec * 1000; #endif - - usec += delta_usec; - if (usec >= 1000000) { - sec += 1; - usec -= 1000000; - } - - 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; - unsigned long delta_nsec; - - if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) - return -EINVAL; - - write_seqlock_irq(&xtime_lock); - - /* The offset that is added into time in do_gettimeofday above - must be subtracted out here to keep a coherent view of the - time. Without this, a full-tick error is possible. */ - -#ifdef CONFIG_SMP - delta_nsec = 0; -#else - delta_nsec = rpcc() - state.last_time; - delta_nsec = (delta_nsec * state.scaled_ticks_per_cycle - + state.partial_tick) * 15625; - delta_nsec = ((delta_nsec / ((1UL << (FIX_SHIFT-6-1)) * HZ)) + 1) / 2; - delta_nsec *= 1000; -#endif - - nsec -= delta_nsec; - - 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); - - /* * In order to set the CMOS clock precisely, set_rtc_mmss has to be * called 500 ms after the second nowtime has started, because when -- cgit v1.2.2