diff options
Diffstat (limited to 'target/linux/coldfire/files-2.6.31/arch/m68k/coldfire/common/time.c')
-rw-r--r-- | target/linux/coldfire/files-2.6.31/arch/m68k/coldfire/common/time.c | 318 |
1 files changed, 318 insertions, 0 deletions
diff --git a/target/linux/coldfire/files-2.6.31/arch/m68k/coldfire/common/time.c b/target/linux/coldfire/files-2.6.31/arch/m68k/coldfire/common/time.c new file mode 100644 index 000000000..a858ce093 --- /dev/null +++ b/target/linux/coldfire/files-2.6.31/arch/m68k/coldfire/common/time.c @@ -0,0 +1,318 @@ +/* + * linux/arch/m68k/coldfire/time.c + * + * This file contains the coldfire specific time handling pieces. + * + * Copyright 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved. + * Kurt Mahan <kmahan@freescale.com> + * Jason Jin Jason.Jin@freescale.com + * Shrek Wu B16972@freescale.com + * + * based on linux/arch/m68k/kernel/time.c + */ +#include <linux/clk.h> +#include <linux/clk.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> +#include <linux/time.h> +#include <linux/timex.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/sysdev.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/param.h> +#include <linux/string.h> +#include <linux/mm.h> +#include <linux/rtc.h> + +#include <asm/machdep.h> +#include <linux/io.h> +#include <asm/irq_regs.h> + +#include <linux/profile.h> +#include <asm/mcfsim.h> +#ifdef CONFIG_GENERIC_CLOCKEVENTS +/*extern unsigned long long sys_dtim0_read(void); +extern void sys_dtim_init(void);*/ +extern unsigned long long sys_dtim2_read(void); +extern void sys_dtim2_init(void); +static int cfv4_set_next_event(unsigned long evt, + struct clock_event_device *dev); +static void cfv4_set_mode(enum clock_event_mode mode, + struct clock_event_device *dev); +#if defined(CONFIG_M5445X) +#define FREQ (MCF_BUSCLK / 16) +#else +#define FREQ (MCF_BUSCLK) +#endif +/* + * realtime clock dummy code + */ + +static unsigned long null_rtc_get_time(void) +{ + return mktime(2008, 1, 1, 0, 0, 0); +} + +static int null_rtc_set_time(unsigned long sec) +{ + return 0; +} + +static unsigned long (*cf_rtc_get_time)(void) = null_rtc_get_time; +static int (*cf_rtc_set_time)(unsigned long) = null_rtc_set_time; +#endif /* CONFIG_GENERIC_CLOCKEVENTS */ + +/* + * old pre-GENERIC clock code + */ + +#ifndef CONFIG_GENERIC_CLOCKEVENTS +/* + * timer_interrupt() needs to keep up the real-time clock, + * as well as call the "do_timer()" routine every clocktick + */ +static irqreturn_t timer_interrupt(int irq, void *dummy) +{ +#ifdef CONFIG_COLDFIRE + /* kick hardware timer if necessary */ + if (mach_tick) + mach_tick(); +#endif + do_timer(1); +#ifndef CONFIG_SMP + update_process_times(user_mode(get_irq_regs())); +#endif + profile_tick(CPU_PROFILING); + +#ifdef CONFIG_HEARTBEAT + /* use power LED as a heartbeat instead -- much more useful + for debugging -- based on the version for PReP by Cort */ + /* acts like an actual heart beat -- ie thump-thump-pause... */ + if (mach_heartbeat) { + unsigned cnt = 0, period = 0, dist = 0; + + if (cnt == 0 || cnt == dist) + mach_heartbeat(1); + else if (cnt == 7 || cnt == dist+7) + mach_heartbeat(0); + + if (++cnt > period) { + cnt = 0; + /* The hyperbolic function below modifies + * the heartbeat period length in dependency + * of the current (5min) load. It goes through + * the points f(0)=126, f(1)=86, f(5)=51, + * f(inf)->30. */ + period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) + + 30; + dist = period / 4; + } + } +#endif /* CONFIG_HEARTBEAT */ + return IRQ_HANDLED; +} + +void __init time_init(void) +{ + struct rtc_time time; + + if (mach_hwclk) { + mach_hwclk(0, &time); + time.tm_year += 1900; + if (time.tm_year < 1970) + time.tm_year += 100; + xtime.tv_sec = mktime(time.tm_year, time.tm_mon, time.tm_mday, + time.tm_hour, time.tm_min, time.tm_sec); + xtime.tv_nsec = 0; + } + wall_to_monotonic.tv_sec = -xtime.tv_sec; + + mach_sched_init(timer_interrupt); +} +#endif /* !CONFIG_GENERIC_CLOCKEVENTS */ + +#ifndef CONFIG_GENERIC_TIME +/* + * This version of gettimeofday has near microsecond resolution. + */ +void do_gettimeofday(struct timeval *tv) +{ + unsigned long flags; + unsigned long seq; + unsigned long usec, sec; + unsigned long max_ntp_tick = tick_usec - tickadj; + + do { + seq = read_seqbegin_irqsave(&xtime_lock, flags); + + usec = mach_gettimeoffset(); + + /* + * If time_adjust is negative then NTP is slowing the clock + * so make sure not to go into next possible interval. + * Better to lose some accuracy than have time go backwards.. + */ + if (unlikely(time_adjust < 0)) + usec = min(usec, max_ntp_tick); + + sec = xtime.tv_sec; + usec += xtime.tv_nsec/1000; + } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); + + + while (usec >= 1000000) { + usec -= 1000000; + sec++; + } + + 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; + + if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) + return -EINVAL; + + write_seqlock_irq(&xtime_lock); + /* This is revolting. We need to set the xtime.tv_nsec + * correctly. However, the value in this location is + * is value at the last tick. + * Discover what correction gettimeofday + * would have done, and then undo it! + */ + nsec -= 1000 * mach_gettimeoffset(); + + 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); +#endif /* !CONFIG_GENERIC_TIME */ + +#ifdef CONFIG_GENERIC_CLOCKEVENTS +/* + * Clock Evnt setup + */ +static struct clock_event_device clockevent_cfv4 = { + .name = "CFV4 timer2even", + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, + .rating = 200, + .shift = 20, + .set_mode = cfv4_set_mode, + .set_next_event = cfv4_set_next_event, +}; + +static int cfv4_set_next_event(unsigned long evt, + struct clock_event_device *dev) +{ + return 0; +} + +static void cfv4_set_mode(enum clock_event_mode mode, + struct clock_event_device *dev) +{ + if (mode != CLOCK_EVT_MODE_ONESHOT) + cfv4_set_next_event((FREQ / HZ), dev); +} + +static int __init cfv4_clockevent_init(void) +{ + clockevent_cfv4.mult = + div_sc(FREQ, NSEC_PER_SEC, + clockevent_cfv4.shift); + clockevent_cfv4.max_delta_ns = + clockevent_delta2ns((FREQ / HZ), + &clockevent_cfv4); + clockevent_cfv4.min_delta_ns = + clockevent_delta2ns(1, &clockevent_cfv4); + + clockevent_cfv4.cpumask = &cpumask_of_cpu(0); + + printk(KERN_INFO "timer: register clockevent\n"); + clockevents_register_device(&clockevent_cfv4); + + return 0; +} + +/* + * clocksource setup + */ + +struct clocksource clocksource_cfv4 = { + .name = "ColdfireV4", + .rating = 250, + .mask = CLOCKSOURCE_MASK(32), + .read = sys_dtim2_read, + .shift = 20, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +/* + * Initialize time subsystem. Called from linux/init/main.c + */ +void __init time_init(void) +{ + int ret; + + printk(KERN_INFO "Initializing time\n"); +#if 0 + /* initialize system clocks */ + clk_init(); +#endif + cfv4_clockevent_init(); + /* initialize the system timer */ + /*sys_dtim_init();*/ + sys_dtim2_init(); + /* setup initial system time */ + xtime.tv_sec = cf_rtc_get_time(); + xtime.tv_nsec = 0; + set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, + -xtime.tv_nsec); + + /* JKM */ + clocksource_cfv4.mult = clocksource_hz2mult(FREQ, + clocksource_cfv4.shift); + + /* register our clocksource */ + ret = clocksource_register(&clocksource_cfv4); + if (ret) + printk(KERN_ERR "timer: unable to " + "register clocksource - %d\n", ret); +} + +/* + * sysfs pieces + */ + +static struct sysdev_class timer_class = { + .name = "timer", +}; + +static struct sys_device timer_device = { + .id = 0, + .cls = &timer_class, +}; + +static int __init timer_init_sysfs(void) +{ + int err = sysdev_class_register(&timer_class); + if (!err) + err = sysdev_register(&timer_device); + return err; +} +device_initcall(timer_init_sysfs); +#endif /* CONFIG_GENERIC_CLOCKEVENTS */ |