From c1d370e167d66b10bca3b602d3740405469383de Mon Sep 17 00:00:00 2001 From: John Stultz Date: Fri, 16 Feb 2007 01:27:31 -0800 Subject: [PATCH] [PATCH] i386: use GTOD persistent clock support Persistent clock support: do proper timekeeping across suspend/resume, i386 arch support. [bunk@stusta.de: cleanup] Build-fixes-from: Andrew Morton Signed-off-by: John Stultz Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar Cc: Roman Zippel Cc: Adrian Bunk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/apm.c | 44 --------------------------------- arch/i386/kernel/time.c | 54 +---------------------------------------- 2 files changed, 1 insertion(+), 97 deletions(-) diff --git a/arch/i386/kernel/apm.c b/arch/i386/kernel/apm.c index f9ba0af7ee..064bbf2861 100644 --- a/arch/i386/kernel/apm.c +++ b/arch/i386/kernel/apm.c @@ -236,7 +236,6 @@ #include "io_ports.h" -extern unsigned long get_cmos_time(void); extern void machine_real_restart(unsigned char *, int); #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT) @@ -1176,28 +1175,6 @@ out: spin_unlock(&user_list_lock); } -static void set_time(void) -{ - struct timespec ts; - if (got_clock_diff) { /* Must know time zone in order to set clock */ - ts.tv_sec = get_cmos_time() + clock_cmos_diff; - ts.tv_nsec = 0; - do_settimeofday(&ts); - } -} - -static void get_time_diff(void) -{ -#ifndef CONFIG_APM_RTC_IS_GMT - /* - * Estimate time zone so that set_time can update the clock - */ - clock_cmos_diff = -get_cmos_time(); - clock_cmos_diff += get_seconds(); - got_clock_diff = 1; -#endif -} - static void reinit_timer(void) { #ifdef INIT_TIMER_AFTER_SUSPEND @@ -1237,19 +1214,6 @@ static int suspend(int vetoable) local_irq_disable(); device_power_down(PMSG_SUSPEND); - /* serialize with the timer interrupt */ - write_seqlock(&xtime_lock); - - /* protect against access to timer chip registers */ - spin_lock(&i8253_lock); - - get_time_diff(); - /* - * Irq spinlock must be dropped around set_system_power_state. - * We'll undo any timer changes due to interrupts below. - */ - spin_unlock(&i8253_lock); - write_sequnlock(&xtime_lock); local_irq_enable(); save_processor_state(); @@ -1258,7 +1222,6 @@ static int suspend(int vetoable) restore_processor_state(); local_irq_disable(); - set_time(); reinit_timer(); if (err == APM_NO_ERROR) @@ -1288,11 +1251,6 @@ static void standby(void) local_irq_disable(); device_power_down(PMSG_SUSPEND); - /* serialize with the timer interrupt */ - write_seqlock(&xtime_lock); - /* If needed, notify drivers here */ - get_time_diff(); - write_sequnlock(&xtime_lock); local_irq_enable(); err = set_system_power_state(APM_STATE_STANDBY); @@ -1386,7 +1344,6 @@ static void check_events(void) ignore_bounce = 1; if ((event != APM_NORMAL_RESUME) || (ignore_normal_resume == 0)) { - set_time(); device_resume(); pm_send_all(PM_RESUME, (void *)0); queue_event(event, NULL); @@ -1402,7 +1359,6 @@ static void check_events(void) break; case APM_UPDATE_TIME: - set_time(); break; case APM_CRITICAL_SUSPEND: diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c index a4f67a6e68..044c17572e 100644 --- a/arch/i386/kernel/time.c +++ b/arch/i386/kernel/time.c @@ -212,7 +212,7 @@ irqreturn_t timer_interrupt(int irq, void *dev_id) } /* not static: needed by APM */ -unsigned long get_cmos_time(void) +unsigned long read_persistent_clock(void) { unsigned long retval; unsigned long flags; @@ -225,7 +225,6 @@ unsigned long get_cmos_time(void) return retval; } -EXPORT_SYMBOL(get_cmos_time); static void sync_cmos_clock(unsigned long dummy); @@ -278,58 +277,19 @@ void notify_arch_cmos_timer(void) mod_timer(&sync_cmos_timer, jiffies + 1); } -static long clock_cmos_diff; -static unsigned long sleep_start; - -static int timer_suspend(struct sys_device *dev, pm_message_t state) -{ - /* - * Estimate time zone so that set_time can update the clock - */ - unsigned long ctime = get_cmos_time(); - - clock_cmos_diff = -ctime; - clock_cmos_diff += get_seconds(); - sleep_start = ctime; - return 0; -} - static int timer_resume(struct sys_device *dev) { - unsigned long flags; - unsigned long sec; - unsigned long ctime = get_cmos_time(); - long sleep_length = (ctime - sleep_start) * HZ; - struct timespec ts; - - if (sleep_length < 0) { - printk(KERN_WARNING "CMOS clock skew detected in timer resume!\n"); - /* The time after the resume must not be earlier than the time - * before the suspend or some nasty things will happen - */ - sleep_length = 0; - ctime = sleep_start; - } #ifdef CONFIG_HPET_TIMER if (is_hpet_enabled()) hpet_reenable(); #endif setup_pit_timer(); - - sec = ctime + clock_cmos_diff; - ts.tv_sec = sec; - ts.tv_nsec = 0; - do_settimeofday(&ts); - write_seqlock_irqsave(&xtime_lock, flags); - jiffies_64 += sleep_length; - write_sequnlock_irqrestore(&xtime_lock, flags); touch_softlockup_watchdog(); return 0; } static struct sysdev_class timer_sysclass = { .resume = timer_resume, - .suspend = timer_suspend, set_kset_name("timer"), }; @@ -355,12 +315,6 @@ extern void (*late_time_init)(void); /* Duplicate of time_init() below, with hpet_enable part added */ static void __init hpet_time_init(void) { - struct timespec ts; - ts.tv_sec = get_cmos_time(); - ts.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ); - - do_settimeofday(&ts); - if ((hpet_enable() >= 0) && hpet_use_timer) { printk("Using HPET for base-timer\n"); } @@ -371,7 +325,6 @@ static void __init hpet_time_init(void) void __init time_init(void) { - struct timespec ts; #ifdef CONFIG_HPET_TIMER if (is_hpet_capable()) { /* @@ -382,10 +335,5 @@ void __init time_init(void) return; } #endif - ts.tv_sec = get_cmos_time(); - ts.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ); - - do_settimeofday(&ts); - do_time_init(); } -- 2.39.5