diff options
Diffstat (limited to 'arch/sh/kernel/time.c')
| -rw-r--r-- | arch/sh/kernel/time.c | 172 |
1 files changed, 55 insertions, 117 deletions
diff --git a/arch/sh/kernel/time.c b/arch/sh/kernel/time.c index d47e775962e..a3a67d151e5 100644 --- a/arch/sh/kernel/time.c +++ b/arch/sh/kernel/time.c @@ -3,7 +3,7 @@ * * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> - * Copyright (C) 2002 - 2006 Paul Mundt + * Copyright (C) 2002 - 2007 Paul Mundt * Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org> * * Some code taken from i386 version. @@ -15,6 +15,7 @@ #include <linux/profile.h> #include <linux/timex.h> #include <linux/sched.h> +#include <linux/clockchips.h> #include <asm/clock.h> #include <asm/rtc.h> #include <asm/timer.h> @@ -38,6 +39,14 @@ static int null_rtc_set_time(const time_t secs) return 0; } +/* + * Null high precision timer functions for systems lacking one. + */ +static cycle_t null_hpt_read(void) +{ + 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; @@ -101,6 +110,7 @@ int do_settimeofday(struct timespec *tv) EXPORT_SYMBOL(do_settimeofday); #endif /* !CONFIG_GENERIC_TIME */ +#ifndef CONFIG_GENERIC_CLOCKEVENTS /* last time the RTC clock got updated */ static long last_rtc_update; @@ -138,6 +148,7 @@ void handle_timer_tick(void) last_rtc_update = xtime.tv_sec - 600; } } +#endif /* !CONFIG_GENERIC_CLOCKEVENTS */ #ifdef CONFIG_PM int timer_suspend(struct sys_device *dev, pm_message_t state) @@ -168,136 +179,58 @@ static struct sysdev_class timer_sysclass = { .resume = timer_resume, }; -#ifdef CONFIG_NO_IDLE_HZ -static int timer_dyn_tick_enable(void) +static int __init timer_init_sysfs(void) { - struct dyn_tick_timer *dyn_tick = sys_timer->dyn_tick; - unsigned long flags; - int ret = -ENODEV; - - if (dyn_tick) { - spin_lock_irqsave(&dyn_tick->lock, flags); - ret = 0; - if (!(dyn_tick->state & DYN_TICK_ENABLED)) { - ret = dyn_tick->enable(); - - if (ret == 0) - dyn_tick->state |= DYN_TICK_ENABLED; - } - spin_unlock_irqrestore(&dyn_tick->lock, flags); - } + int ret = sysdev_class_register(&timer_sysclass); + if (ret != 0) + return ret; - return ret; + sys_timer->dev.cls = &timer_sysclass; + return sysdev_register(&sys_timer->dev); } +device_initcall(timer_init_sysfs); -static int timer_dyn_tick_disable(void) -{ - struct dyn_tick_timer *dyn_tick = sys_timer->dyn_tick; - unsigned long flags; - int ret = -ENODEV; - - if (dyn_tick) { - spin_lock_irqsave(&dyn_tick->lock, flags); - ret = 0; - if (dyn_tick->state & DYN_TICK_ENABLED) { - ret = dyn_tick->disable(); - - if (ret == 0) - dyn_tick->state &= ~DYN_TICK_ENABLED; - } - spin_unlock_irqrestore(&dyn_tick->lock, flags); - } - - return ret; -} +void (*board_time_init)(void); /* - * Reprogram the system timer for at least the calculated time interval. - * This function should be called from the idle thread with IRQs disabled, - * immediately before sleeping. + * Shamelessly based on the MIPS and Sparc64 work. */ -void timer_dyn_reprogram(void) -{ - struct dyn_tick_timer *dyn_tick = sys_timer->dyn_tick; - unsigned long next, seq, flags; - - if (!dyn_tick) - return; - - spin_lock_irqsave(&dyn_tick->lock, flags); - if (dyn_tick->state & DYN_TICK_ENABLED) { - next = next_timer_interrupt(); - do { - seq = read_seqbegin(&xtime_lock); - dyn_tick->reprogram(next - jiffies); - } while (read_seqretry(&xtime_lock, seq)); - } - spin_unlock_irqrestore(&dyn_tick->lock, flags); -} +static unsigned long timer_ticks_per_nsec_quotient __read_mostly; +unsigned long sh_hpt_frequency = 0; + +#define NSEC_PER_CYC_SHIFT 10 + +struct clocksource clocksource_sh = { + .name = "SuperH", + .rating = 200, + .mask = CLOCKSOURCE_MASK(32), + .read = null_hpt_read, + .shift = 16, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; -static ssize_t timer_show_dyn_tick(struct sys_device *dev, char *buf) +static void __init init_sh_clocksource(void) { - return sprintf(buf, "%i\n", - (sys_timer->dyn_tick->state & DYN_TICK_ENABLED) >> 1); -} + if (!sh_hpt_frequency || clocksource_sh.read == null_hpt_read) + return; -static ssize_t timer_set_dyn_tick(struct sys_device *dev, const char *buf, - size_t count) -{ - unsigned int enable = simple_strtoul(buf, NULL, 2); + clocksource_sh.mult = clocksource_hz2mult(sh_hpt_frequency, + clocksource_sh.shift); - if (enable) - timer_dyn_tick_enable(); - else - timer_dyn_tick_disable(); + timer_ticks_per_nsec_quotient = + clocksource_hz2mult(sh_hpt_frequency, NSEC_PER_CYC_SHIFT); - return count; + clocksource_register(&clocksource_sh); } -static SYSDEV_ATTR(dyn_tick, 0644, timer_show_dyn_tick, timer_set_dyn_tick); -/* - * dyntick=enable|disable - */ -static char dyntick_str[4] __initdata = ""; - -static int __init dyntick_setup(char *str) +#ifdef CONFIG_GENERIC_TIME +unsigned long long sched_clock(void) { - if (str) - strlcpy(dyntick_str, str, sizeof(dyntick_str)); - return 1; + unsigned long long ticks = clocksource_sh.read(); + return (ticks * timer_ticks_per_nsec_quotient) >> NSEC_PER_CYC_SHIFT; } - -__setup("dyntick=", dyntick_setup); -#endif - -static int __init timer_init_sysfs(void) -{ - int ret = sysdev_class_register(&timer_sysclass); - if (ret != 0) - return ret; - - sys_timer->dev.cls = &timer_sysclass; - ret = sysdev_register(&sys_timer->dev); - -#ifdef CONFIG_NO_IDLE_HZ - if (ret == 0 && sys_timer->dyn_tick) { - ret = sysdev_create_file(&sys_timer->dev, &attr_dyn_tick); - - /* - * Turn on dynamic tick after calibrate delay - * for correct bogomips - */ - if (ret == 0 && dyntick_str[0] == 'e') - ret = timer_dyn_tick_enable(); - } #endif - return ret; -} -device_initcall(timer_init_sysfs); - -void (*board_time_init)(void); - void __init time_init(void) { if (board_time_init) @@ -316,10 +249,15 @@ void __init time_init(void) sys_timer = get_sys_timer(); printk(KERN_INFO "Using %s for system timer\n", sys_timer->name); -#ifdef CONFIG_NO_IDLE_HZ - if (sys_timer->dyn_tick) - spin_lock_init(&sys_timer->dyn_tick->lock); -#endif + if (sys_timer->ops->read) + clocksource_sh.read = sys_timer->ops->read; + + init_sh_clocksource(); + + if (sh_hpt_frequency) + printk("Using %lu.%03lu MHz high precision timer.\n", + ((sh_hpt_frequency + 500) / 1000) / 1000, + ((sh_hpt_frequency + 500) / 1000) % 1000); #if defined(CONFIG_SH_KGDB) /* |