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-rw-r--r--arch/um/kernel/time_kern.c203
1 files changed, 203 insertions, 0 deletions
diff --git a/arch/um/kernel/time_kern.c b/arch/um/kernel/time_kern.c
new file mode 100644
index 0000000..2461cd7
--- /dev/null
+++ b/arch/um/kernel/time_kern.c
@@ -0,0 +1,203 @@
+/*
+ * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include "linux/kernel.h"
+#include "linux/module.h"
+#include "linux/unistd.h"
+#include "linux/stddef.h"
+#include "linux/spinlock.h"
+#include "linux/time.h"
+#include "linux/sched.h"
+#include "linux/interrupt.h"
+#include "linux/init.h"
+#include "linux/delay.h"
+#include "asm/irq.h"
+#include "asm/param.h"
+#include "asm/current.h"
+#include "kern_util.h"
+#include "user_util.h"
+#include "time_user.h"
+#include "mode.h"
+#include "os.h"
+
+u64 jiffies_64 = INITIAL_JIFFIES;
+
+EXPORT_SYMBOL(jiffies_64);
+
+int hz(void)
+{
+ return(HZ);
+}
+
+/*
+ * Scheduler clock - returns current time in nanosec units.
+ */
+unsigned long long sched_clock(void)
+{
+ return (unsigned long long)jiffies_64 * (1000000000 / HZ);
+}
+
+/* Changed at early boot */
+int timer_irq_inited = 0;
+
+static int first_tick;
+static unsigned long long prev_usecs;
+#ifdef CONFIG_UML_REAL_TIME_CLOCK
+static long long delta; /* Deviation per interval */
+#endif
+
+#define MILLION 1000000
+
+void timer_irq(union uml_pt_regs *regs)
+{
+ unsigned long long ticks = 0;
+
+ if(!timer_irq_inited){
+ /* This is to ensure that ticks don't pile up when
+ * the timer handler is suspended */
+ first_tick = 0;
+ return;
+ }
+
+ if(first_tick){
+#ifdef CONFIG_UML_REAL_TIME_CLOCK
+ /* We've had 1 tick */
+ unsigned long long usecs = os_usecs();
+
+ delta += usecs - prev_usecs;
+ prev_usecs = usecs;
+
+ /* Protect against the host clock being set backwards */
+ if(delta < 0)
+ delta = 0;
+
+ ticks += (delta * HZ) / MILLION;
+ delta -= (ticks * MILLION) / HZ;
+#else
+ ticks = 1;
+#endif
+ }
+ else {
+ prev_usecs = os_usecs();
+ first_tick = 1;
+ }
+
+ while(ticks > 0){
+ do_IRQ(TIMER_IRQ, regs);
+ ticks--;
+ }
+}
+
+void boot_timer_handler(int sig)
+{
+ struct pt_regs regs;
+
+ CHOOSE_MODE((void)
+ (UPT_SC(&regs.regs) = (struct sigcontext *) (&sig + 1)),
+ (void) (regs.regs.skas.is_user = 0));
+ do_timer(&regs);
+}
+
+irqreturn_t um_timer(int irq, void *dev, struct pt_regs *regs)
+{
+ unsigned long flags;
+
+ do_timer(regs);
+ write_seqlock_irqsave(&xtime_lock, flags);
+ timer();
+ write_sequnlock_irqrestore(&xtime_lock, flags);
+ return(IRQ_HANDLED);
+}
+
+long um_time(int __user *tloc)
+{
+ struct timeval now;
+
+ do_gettimeofday(&now);
+ if (tloc) {
+ if (put_user(now.tv_sec, tloc))
+ now.tv_sec = -EFAULT;
+ }
+ return now.tv_sec;
+}
+
+long um_stime(int __user *tptr)
+{
+ int value;
+ struct timespec new;
+
+ if (get_user(value, tptr))
+ return -EFAULT;
+ new.tv_sec = value;
+ new.tv_nsec = 0;
+ do_settimeofday(&new);
+ return 0;
+}
+
+void __udelay(unsigned long usecs)
+{
+ int i, n;
+
+ n = (loops_per_jiffy * HZ * usecs) / MILLION;
+ for(i=0;i<n;i++) ;
+}
+
+void __const_udelay(unsigned long usecs)
+{
+ int i, n;
+
+ n = (loops_per_jiffy * HZ * usecs) / MILLION;
+ for(i=0;i<n;i++) ;
+}
+
+void timer_handler(int sig, union uml_pt_regs *regs)
+{
+ local_irq_disable();
+ update_process_times(CHOOSE_MODE(user_context(UPT_SP(regs)), (regs)->skas.is_user));
+ local_irq_enable();
+ if(current_thread->cpu == 0)
+ timer_irq(regs);
+}
+
+static DEFINE_SPINLOCK(timer_spinlock);
+
+unsigned long time_lock(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&timer_spinlock, flags);
+ return(flags);
+}
+
+void time_unlock(unsigned long flags)
+{
+ spin_unlock_irqrestore(&timer_spinlock, flags);
+}
+
+int __init timer_init(void)
+{
+ int err;
+
+ CHOOSE_MODE(user_time_init_tt(), user_time_init_skas());
+ err = request_irq(TIMER_IRQ, um_timer, SA_INTERRUPT, "timer", NULL);
+ if(err != 0)
+ printk(KERN_ERR "timer_init : request_irq failed - "
+ "errno = %d\n", -err);
+ timer_irq_inited = 1;
+ return(0);
+}
+
+__initcall(timer_init);
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only. This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
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