1 files changed, 402 insertions, 0 deletions

diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c
new file mode 100644
index 000000000000..c232f24f4a60
--- /dev/null
+++ b/arch/arm/kernel/time.c
@@ -0,0 +1,402 @@
+/*
+ *  linux/arch/arm/kernel/time.c
+ *
+ *  Copyright (C) 1991, 1992, 1995  Linus Torvalds
+ *  Modifications for ARM (C) 1994-2001 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  This file contains the ARM-specific time handling details:
+ *  reading the RTC at bootup, etc...
+ *
+ *  1994-07-02  Alan Modra
+ *              fixed set_rtc_mmss, fixed time.year for >= 2000, new mktime
+ *  1998-12-20  Updated NTP code according to technical memorandum Jan '96
+ *              "A Kernel Model for Precision Timekeeping" by Dave Mills
+ */
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/timex.h>
+#include <linux/errno.h>
+#include <linux/profile.h>
+#include <linux/sysdev.h>
+#include <linux/timer.h>
+
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/leds.h>
+#include <asm/thread_info.h>
+#include <asm/mach/time.h>
+
+u64 jiffies_64 = INITIAL_JIFFIES;
+
+EXPORT_SYMBOL(jiffies_64);
+
+/*
+ * Our system timer.
+ */
+struct sys_timer *system_timer;
+
+extern unsigned long wall_jiffies;
+
+/* this needs a better home */
+DEFINE_SPINLOCK(rtc_lock);
+
+#ifdef CONFIG_SA1100_RTC_MODULE
+EXPORT_SYMBOL(rtc_lock);
+#endif
+
+/* change this if you have some constant time drift */
+#define USECS_PER_JIFFY (1000000/HZ)
+
+#ifdef CONFIG_SMP
+unsigned long profile_pc(struct pt_regs *regs)
+{
+        unsigned long fp, pc = instruction_pointer(regs);
+
+        if (in_lock_functions(pc)) {
+                fp = regs->ARM_fp;
+                pc = pc_pointer(((unsigned long *)fp)[-1]);
+        }
+
+        return pc;
+}
+EXPORT_SYMBOL(profile_pc);
+#endif
+
+/*
+ * hook for setting the RTC's idea of the current time.
+ */
+int (*set_rtc)(void);
+
+static unsigned long dummy_gettimeoffset(void)
+{
+        return 0;
+}
+
+/*
+ * Scheduler clock - returns current time in nanosec units.
+ * This is the default implementation.  Sub-architecture
+ * implementations can override this.
+ */
+unsigned long long __attribute__((weak)) sched_clock(void)
+{
+        return (unsigned long long)jiffies * (1000000000 / HZ);
+}
+
+static unsigned long next_rtc_update;
+
+/*
+ * If we have an externally synchronized linux clock, then update
+ * CMOS clock accordingly every ~11 minutes.  set_rtc() has to be
+ * called as close as possible to 500 ms before the new second
+ * starts.
+ */
+static inline void do_set_rtc(void)
+{
+        if (time_status & STA_UNSYNC || set_rtc == NULL)
+                return;
+
+        if (next_rtc_update &&
+            time_before((unsigned long)xtime.tv_sec, next_rtc_update))
+                return;
+
+        if (xtime.tv_nsec < 500000000 - ((unsigned) tick_nsec >> 1) &&
+            xtime.tv_nsec >= 500000000 + ((unsigned) tick_nsec >> 1))
+                return;
+
+        if (set_rtc())
+                /*
+                 * rtc update failed.  Try again in 60s
+                 */
+                next_rtc_update = xtime.tv_sec + 60;
+        else
+                next_rtc_update = xtime.tv_sec + 660;
+}
+
+#ifdef CONFIG_LEDS
+
+static void dummy_leds_event(led_event_t evt)
+{
+}
+
+void (*leds_event)(led_event_t) = dummy_leds_event;
+
+struct leds_evt_name {
+        const char      name[8];
+        int             on;
+        int             off;
+};
+
+static const struct leds_evt_name evt_names[] = {
+        { "amber", led_amber_on, led_amber_off },
+        { "blue",  led_blue_on,  led_blue_off  },
+        { "green", led_green_on, led_green_off },
+        { "red",   led_red_on,   led_red_off   },
+};
+
+static ssize_t leds_store(struct sys_device *dev, const char *buf, size_t size)
+{
+        int ret = -EINVAL, len = strcspn(buf, " ");
+
+        if (len > 0 && buf[len] == '\0')
+                len--;
+
+        if (strncmp(buf, "claim", len) == 0) {
+                leds_event(led_claim);
+                ret = size;
+        } else if (strncmp(buf, "release", len) == 0) {
+                leds_event(led_release);
+                ret = size;
+        } else {
+                int i;
+
+                for (i = 0; i < ARRAY_SIZE(evt_names); i++) {
+                        if (strlen(evt_names[i].name) != len ||
+                            strncmp(buf, evt_names[i].name, len) != 0)
+                                continue;
+                        if (strncmp(buf+len, " on", 3) == 0) {
+                                leds_event(evt_names[i].on);
+                                ret = size;
+                        } else if (strncmp(buf+len, " off", 4) == 0) {
+                                leds_event(evt_names[i].off);
+                                ret = size;
+                        }
+                        break;
+                }
+        }
+        return ret;
+}
+
+static SYSDEV_ATTR(event, 0200, NULL, leds_store);
+
+static int leds_suspend(struct sys_device *dev, pm_message_t state)
+{
+        leds_event(led_stop);
+        return 0;
+}
+
+static int leds_resume(struct sys_device *dev)
+{
+        leds_event(led_start);
+        return 0;
+}
+
+static int leds_shutdown(struct sys_device *dev)
+{
+        leds_event(led_halted);
+        return 0;
+}
+
+static struct sysdev_class leds_sysclass = {
+        set_kset_name("leds"),
+        .shutdown       = leds_shutdown,
+        .suspend        = leds_suspend,
+        .resume         = leds_resume,
+};
+
+static struct sys_device leds_device = {
+        .id             = 0,
+        .cls            = &leds_sysclass,
+};
+
+static int __init leds_init(void)
+{
+        int ret;
+        ret = sysdev_class_register(&leds_sysclass);
+        if (ret == 0)
+                ret = sysdev_register(&leds_device);
+        if (ret == 0)
+                ret = sysdev_create_file(&leds_device, &attr_event);
+        return ret;
+}
+
+device_initcall(leds_init);
+
+EXPORT_SYMBOL(leds_event);
+#endif
+
+#ifdef CONFIG_LEDS_TIMER
+static inline void do_leds(void)
+{
+        static unsigned int count = 50;
+
+        if (--count == 0) {
+                count = 50;
+                leds_event(led_timer);
+        }
+}
+#else
+#define do_leds()
+#endif
+
+void do_gettimeofday(struct timeval *tv)
+{
+        unsigned long flags;
+        unsigned long seq;
+        unsigned long usec, sec, lost;
+
+        do {
+                seq = read_seqbegin_irqsave(&xtime_lock, flags);
+                usec = system_timer->offset();
+
+                lost = jiffies - wall_jiffies;
+                if (lost)
+                        usec += lost * USECS_PER_JIFFY;
+
+                sec = xtime.tv_sec;
+                usec += xtime.tv_nsec / 1000;
+        } while (read_seqretry_irqrestore(&xtime_lock, seq, flags));
+
+        /* usec may have gone up a lot: be safe */
+        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 "xtime" correctly. However, the
+         * value in this location is the value at the most recent update of
+         * wall time.  Discover what correction gettimeofday() would have
+         * done, and then undo it!
+         */
+        nsec -= system_timer->offset() * NSEC_PER_USEC;
+        nsec -= (jiffies - wall_jiffies) * TICK_NSEC;
+
+        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);
+
+        time_adjust = 0;                /* stop active adjtime() */
+        time_status |= STA_UNSYNC;
+        time_maxerror = NTP_PHASE_LIMIT;
+        time_esterror = NTP_PHASE_LIMIT;
+        write_sequnlock_irq(&xtime_lock);
+        clock_was_set();
+        return 0;
+}
+
+EXPORT_SYMBOL(do_settimeofday);
+
+/**
+ * save_time_delta - Save the offset between system time and RTC time
+ * @delta: pointer to timespec to store delta
+ * @rtc: pointer to timespec for current RTC time
+ *
+ * Return a delta between the system time and the RTC time, such
+ * that system time can be restored later with restore_time_delta()
+ */
+void save_time_delta(struct timespec *delta, struct timespec *rtc)
+{
+        set_normalized_timespec(delta,
+                                xtime.tv_sec - rtc->tv_sec,
+                                xtime.tv_nsec - rtc->tv_nsec);
+}
+EXPORT_SYMBOL(save_time_delta);
+
+/**
+ * restore_time_delta - Restore the current system time
+ * @delta: delta returned by save_time_delta()
+ * @rtc: pointer to timespec for current RTC time
+ */
+void restore_time_delta(struct timespec *delta, struct timespec *rtc)
+{
+        struct timespec ts;
+
+        set_normalized_timespec(&ts,
+                                delta->tv_sec + rtc->tv_sec,
+                                delta->tv_nsec + rtc->tv_nsec);
+
+        do_settimeofday(&ts);
+}
+EXPORT_SYMBOL(restore_time_delta);
+
+/*
+ * Kernel system timer support.
+ */
+void timer_tick(struct pt_regs *regs)
+{
+        profile_tick(CPU_PROFILING, regs);
+        do_leds();
+        do_set_rtc();
+        do_timer(regs);
+#ifndef CONFIG_SMP
+        update_process_times(user_mode(regs));
+#endif
+}
+
+#ifdef CONFIG_PM
+static int timer_suspend(struct sys_device *dev, pm_message_t state)
+{
+        struct sys_timer *timer = container_of(dev, struct sys_timer, dev);
+
+        if (timer->suspend != NULL)
+                timer->suspend();
+
+        return 0;
+}
+
+static int timer_resume(struct sys_device *dev)
+{
+        struct sys_timer *timer = container_of(dev, struct sys_timer, dev);
+
+        if (timer->resume != NULL)
+                timer->resume();
+
+        return 0;
+}
+#else
+#define timer_suspend NULL
+#define timer_resume NULL
+#endif
+
+static struct sysdev_class timer_sysclass = {
+        set_kset_name("timer"),
+        .suspend        = timer_suspend,
+        .resume         = timer_resume,
+};
+
+static int __init timer_init_sysfs(void)
+{
+        int ret = sysdev_class_register(&timer_sysclass);
+        if (ret == 0) {
+                system_timer->dev.cls = &timer_sysclass;
+                ret = sysdev_register(&system_timer->dev);
+        }
+        return ret;
+}
+
+device_initcall(timer_init_sysfs);
+
+void __init time_init(void)
+{
+        if (system_timer->offset == NULL)
+                system_timer->offset = dummy_gettimeoffset;
+        system_timer->init();
+}
+