diff options
author | john stultz <johnstul@us.ibm.com> | 2009-09-21 20:04:00 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-22 10:17:43 -0400 |
commit | 4f543fa41e78bd366123424a3378f2f4918c0f33 (patch) | |
tree | bf6e9fdb30c41de9833dcf2a363177ea0dc28a5d /arch/alpha/kernel | |
parent | 6e0c9e77771e08b171c4abeb073285d8fb03f528 (diff) |
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 <johnstul@us.ibm.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/alpha/kernel')
-rw-r--r-- | arch/alpha/kernel/time.c | 79 |
1 files changed, 7 insertions, 72 deletions
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) | |||
408 | * part. So we can't do the "find absolute time in terms of cycles" thing | 408 | * part. So we can't do the "find absolute time in terms of cycles" thing |
409 | * that the other ports do. | 409 | * that the other ports do. |
410 | */ | 410 | */ |
411 | void | 411 | u32 arch_gettimeoffset(void) |
412 | do_gettimeofday(struct timeval *tv) | ||
413 | { | 412 | { |
414 | unsigned long flags; | ||
415 | unsigned long sec, usec, seq; | ||
416 | unsigned long delta_cycles, delta_usec, partial_tick; | ||
417 | |||
418 | do { | ||
419 | seq = read_seqbegin_irqsave(&xtime_lock, flags); | ||
420 | |||
421 | delta_cycles = rpcc() - state.last_time; | ||
422 | sec = xtime.tv_sec; | ||
423 | usec = (xtime.tv_nsec / 1000); | ||
424 | partial_tick = state.partial_tick; | ||
425 | |||
426 | } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); | ||
427 | |||
428 | #ifdef CONFIG_SMP | 413 | #ifdef CONFIG_SMP |
429 | /* Until and unless we figure out how to get cpu cycle counters | 414 | /* Until and unless we figure out how to get cpu cycle counters |
430 | in sync and keep them there, we can't use the rpcc tricks. */ | 415 | in sync and keep them there, we can't use the rpcc tricks. */ |
431 | delta_usec = 0; | 416 | return 0; |
432 | #else | 417 | #else |
418 | unsigned long delta_cycles, delta_usec, partial_tick; | ||
419 | |||
420 | delta_cycles = rpcc() - state.last_time; | ||
421 | partial_tick = state.partial_tick; | ||
433 | /* | 422 | /* |
434 | * usec = cycles * ticks_per_cycle * 2**48 * 1e6 / (2**48 * ticks) | 423 | * usec = cycles * ticks_per_cycle * 2**48 * 1e6 / (2**48 * ticks) |
435 | * = cycles * (s_t_p_c) * 1e6 / (2**48 * ticks) | 424 | * = cycles * (s_t_p_c) * 1e6 / (2**48 * ticks) |
@@ -446,64 +435,10 @@ do_gettimeofday(struct timeval *tv) | |||
446 | delta_usec = (delta_cycles * state.scaled_ticks_per_cycle | 435 | delta_usec = (delta_cycles * state.scaled_ticks_per_cycle |
447 | + partial_tick) * 15625; | 436 | + partial_tick) * 15625; |
448 | delta_usec = ((delta_usec / ((1UL << (FIX_SHIFT-6-1)) * HZ)) + 1) / 2; | 437 | delta_usec = ((delta_usec / ((1UL << (FIX_SHIFT-6-1)) * HZ)) + 1) / 2; |
438 | return delta_usec * 1000; | ||
449 | #endif | 439 | #endif |
450 | |||
451 | usec += delta_usec; | ||
452 | if (usec >= 1000000) { | ||
453 | sec += 1; | ||
454 | usec -= 1000000; | ||
455 | } | ||
456 | |||
457 | tv->tv_sec = sec; | ||
458 | tv->tv_usec = usec; | ||
459 | } | 440 | } |
460 | 441 | ||
461 | EXPORT_SYMBOL(do_gettimeofday); | ||
462 | |||
463 | int | ||
464 | do_settimeofday(struct timespec *tv) | ||
465 | { | ||
466 | time_t wtm_sec, sec = tv->tv_sec; | ||
467 | long wtm_nsec, nsec = tv->tv_nsec; | ||
468 | unsigned long delta_nsec; | ||
469 | |||
470 | if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) | ||
471 | return -EINVAL; | ||
472 | |||
473 | write_seqlock_irq(&xtime_lock); | ||
474 | |||
475 | /* The offset that is added into time in do_gettimeofday above | ||
476 | must be subtracted out here to keep a coherent view of the | ||
477 | time. Without this, a full-tick error is possible. */ | ||
478 | |||
479 | #ifdef CONFIG_SMP | ||
480 | delta_nsec = 0; | ||
481 | #else | ||
482 | delta_nsec = rpcc() - state.last_time; | ||
483 | delta_nsec = (delta_nsec * state.scaled_ticks_per_cycle | ||
484 | + state.partial_tick) * 15625; | ||
485 | delta_nsec = ((delta_nsec / ((1UL << (FIX_SHIFT-6-1)) * HZ)) + 1) / 2; | ||
486 | delta_nsec *= 1000; | ||
487 | #endif | ||
488 | |||
489 | nsec -= delta_nsec; | ||
490 | |||
491 | wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec); | ||
492 | wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); | ||
493 | |||
494 | set_normalized_timespec(&xtime, sec, nsec); | ||
495 | set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); | ||
496 | |||
497 | ntp_clear(); | ||
498 | |||
499 | write_sequnlock_irq(&xtime_lock); | ||
500 | clock_was_set(); | ||
501 | return 0; | ||
502 | } | ||
503 | |||
504 | EXPORT_SYMBOL(do_settimeofday); | ||
505 | |||
506 | |||
507 | /* | 442 | /* |
508 | * In order to set the CMOS clock precisely, set_rtc_mmss has to be | 443 | * In order to set the CMOS clock precisely, set_rtc_mmss has to be |
509 | * called 500 ms after the second nowtime has started, because when | 444 | * called 500 ms after the second nowtime has started, because when |