| /* |
| * 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 "linux/hrtimer.h" |
| #include "asm/irq.h" |
| #include "asm/param.h" |
| #include "asm/current.h" |
| #include "kern_util.h" |
| #include "user_util.h" |
| #include "mode.h" |
| #include "os.h" |
| |
| 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); |
| } |
| |
| static unsigned long long prev_nsecs; |
| #ifdef CONFIG_UML_REAL_TIME_CLOCK |
| static long long delta; /* Deviation per interval */ |
| #endif |
| |
| void timer_irq(union uml_pt_regs *regs) |
| { |
| unsigned long long ticks = 0; |
| |
| #ifdef CONFIG_UML_REAL_TIME_CLOCK |
| if(prev_nsecs){ |
| /* We've had 1 tick */ |
| unsigned long long nsecs = os_nsecs(); |
| |
| delta += nsecs - prev_nsecs; |
| prev_nsecs = nsecs; |
| |
| /* Protect against the host clock being set backwards */ |
| if(delta < 0) |
| delta = 0; |
| |
| ticks += (delta * HZ) / BILLION; |
| delta -= (ticks * BILLION) / HZ; |
| } |
| else prev_nsecs = os_nsecs(); |
| #else |
| ticks = 1; |
| #endif |
| while(ticks > 0){ |
| do_IRQ(TIMER_IRQ, regs); |
| ticks--; |
| } |
| } |
| |
| static DEFINE_SPINLOCK(timer_spinlock); |
| |
| static unsigned long long local_offset = 0; |
| |
| static inline unsigned long long get_time(void) |
| { |
| unsigned long long nsecs; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&timer_spinlock, flags); |
| nsecs = os_nsecs(); |
| nsecs += local_offset; |
| spin_unlock_irqrestore(&timer_spinlock, flags); |
| |
| return nsecs; |
| } |
| |
| irqreturn_t um_timer(int irq, void *dev, struct pt_regs *regs) |
| { |
| unsigned long long nsecs; |
| unsigned long flags; |
| |
| write_seqlock_irqsave(&xtime_lock, flags); |
| |
| do_timer(regs); |
| |
| nsecs = get_time() + local_offset; |
| xtime.tv_sec = nsecs / NSEC_PER_SEC; |
| xtime.tv_nsec = nsecs - xtime.tv_sec * NSEC_PER_SEC; |
| |
| write_sequnlock_irqrestore(&xtime_lock, flags); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static void register_timer(void) |
| { |
| int err; |
| |
| err = request_irq(TIMER_IRQ, um_timer, IRQF_DISABLED, "timer", NULL); |
| if(err != 0) |
| printk(KERN_ERR "register_timer : request_irq failed - " |
| "errno = %d\n", -err); |
| |
| err = set_interval(1); |
| if(err != 0) |
| printk(KERN_ERR "register_timer : set_interval failed - " |
| "errno = %d\n", -err); |
| } |
| |
| extern void (*late_time_init)(void); |
| |
| void time_init(void) |
| { |
| long long nsecs; |
| |
| nsecs = os_nsecs(); |
| set_normalized_timespec(&wall_to_monotonic, -nsecs / BILLION, |
| -nsecs % BILLION); |
| late_time_init = register_timer; |
| } |
| |
| void do_gettimeofday(struct timeval *tv) |
| { |
| unsigned long long nsecs = get_time(); |
| |
| tv->tv_sec = nsecs / NSEC_PER_SEC; |
| /* Careful about calculations here - this was originally done as |
| * (nsecs - tv->tv_sec * NSEC_PER_SEC) / NSEC_PER_USEC |
| * which gave bogus (> 1000000) values. Dunno why, suspect gcc |
| * (4.0.0) miscompiled it, or there's a subtle 64/32-bit conversion |
| * problem that I missed. |
| */ |
| nsecs -= tv->tv_sec * NSEC_PER_SEC; |
| tv->tv_usec = (unsigned long) nsecs / NSEC_PER_USEC; |
| } |
| |
| static inline void set_time(unsigned long long nsecs) |
| { |
| unsigned long long now; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&timer_spinlock, flags); |
| now = os_nsecs(); |
| local_offset = nsecs - now; |
| spin_unlock_irqrestore(&timer_spinlock, flags); |
| |
| clock_was_set(); |
| } |
| |
| int do_settimeofday(struct timespec *tv) |
| { |
| set_time((unsigned long long) tv->tv_sec * NSEC_PER_SEC + tv->tv_nsec); |
| |
| return 0; |
| } |
| |
| void timer_handler(int sig, union uml_pt_regs *regs) |
| { |
| local_irq_disable(); |
| irq_enter(); |
| update_process_times(CHOOSE_MODE( |
| (UPT_SC(regs) && user_context(UPT_SP(regs))), |
| (regs)->skas.is_user)); |
| irq_exit(); |
| local_irq_enable(); |
| if(current_thread->cpu == 0) |
| timer_irq(regs); |
| } |