linux/arch/sh/kernel/time.c
Paul Mundt 780f98ff1f sh: Account for INITIAL_JIFFIES when using jiffies clocksource.
In the case where we fall back on the generic jiffies clocksource,
INITIAL_JIFFIES needs to be accounted for so that printk times aren't
completely skewed.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-05-11 12:15:14 +09:00

151 lines
3.2 KiB
C

/*
* arch/sh/kernel/time.c
*
* Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
* Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
* Copyright (C) 2002 - 2009 Paul Mundt
* Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org>
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/profile.h>
#include <linux/timex.h>
#include <linux/sched.h>
#include <linux/clockchips.h>
#include <linux/platform_device.h>
#include <linux/smp.h>
#include <linux/rtc.h>
#include <asm/clock.h>
#include <asm/rtc.h>
#include <asm/timer.h>
struct sys_timer *sys_timer;
/* Dummy RTC ops */
static void null_rtc_get_time(struct timespec *tv)
{
tv->tv_sec = mktime(2000, 1, 1, 0, 0, 0);
tv->tv_nsec = 0;
}
static int null_rtc_set_time(const time_t secs)
{
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;
#ifdef CONFIG_GENERIC_CMOS_UPDATE
unsigned long read_persistent_clock(void)
{
struct timespec tv;
rtc_sh_get_time(&tv);
return tv.tv_sec;
}
int update_persistent_clock(struct timespec now)
{
return rtc_sh_set_time(now.tv_sec);
}
#endif
unsigned int get_rtc_time(struct rtc_time *tm)
{
if (rtc_sh_get_time != null_rtc_get_time) {
struct timespec tv;
rtc_sh_get_time(&tv);
rtc_time_to_tm(tv.tv_sec, tm);
}
return RTC_24H;
}
EXPORT_SYMBOL(get_rtc_time);
int set_rtc_time(struct rtc_time *tm)
{
unsigned long secs;
rtc_tm_to_time(tm, &secs);
return rtc_sh_set_time(secs);
}
EXPORT_SYMBOL(set_rtc_time);
static int __init rtc_generic_init(void)
{
struct platform_device *pdev;
if (rtc_sh_get_time == null_rtc_get_time)
return -ENODEV;
pdev = platform_device_register_simple("rtc-generic", -1, NULL, 0);
if (IS_ERR(pdev))
return PTR_ERR(pdev);
return 0;
}
module_init(rtc_generic_init);
void (*board_time_init)(void);
struct clocksource clocksource_sh = {
.name = "SuperH",
};
unsigned long long sched_clock(void)
{
unsigned long long cycles;
/* jiffies based sched_clock if no clocksource is installed */
if (!clocksource_sh.rating)
return (jiffies_64 - INITIAL_JIFFIES) * (NSEC_PER_SEC / HZ);
cycles = clocksource_sh.read(&clocksource_sh);
return cyc2ns(&clocksource_sh, cycles);
}
static void __init sh_late_time_init(void)
{
/*
* Make sure all compiled-in early timers register themselves.
* Run probe() for one "earlytimer" device.
*/
early_platform_driver_register_all("earlytimer");
if (early_platform_driver_probe("earlytimer", 1, 0))
return;
/*
* Find the timer to use as the system timer, it will be
* initialized for us.
*/
sys_timer = get_sys_timer();
if (unlikely(!sys_timer))
panic("System timer missing.\n");
printk(KERN_INFO "Using %s for system timer\n", sys_timer->name);
}
void __init time_init(void)
{
if (board_time_init)
board_time_init();
clk_init();
rtc_sh_get_time(&xtime);
set_normalized_timespec(&wall_to_monotonic,
-xtime.tv_sec, -xtime.tv_nsec);
#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
local_timer_setup(smp_processor_id());
#endif
late_time_init = sh_late_time_init;
}