LXR linux/include/asm-arm/mach/time.h

   1/*
   2 * linux/include/asm-arm/mach/time.h
   3 *
   4 * Copyright (C) 2004 MontaVista Software, Inc.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 */
  10#ifndef __ASM_ARM_MACH_TIME_H
  11#define __ASM_ARM_MACH_TIME_H
  12
  13#include <linux/sysdev.h>
  14
  15/*
  16 * This is our kernel timer structure.
  17 *
  18 * - init
  19 *   Initialise the kernels jiffy timer source, claim interrupt
  20 *   using setup_irq.  This is called early on during initialisation
  21 *   while interrupts are still disabled on the local CPU.
  22 * - suspend
  23 *   Suspend the kernel jiffy timer source, if necessary.  This
  24 *   is called with interrupts disabled, after all normal devices
  25 *   have been suspended.  If no action is required, set this to
  26 *   NULL.
  27 * - resume
  28 *   Resume the kernel jiffy timer source, if necessary.  This
  29 *   is called with interrupts disabled before any normal devices
  30 *   are resumed.  If no action is required, set this to NULL.
  31 * - offset
  32 *   Return the timer offset in microseconds since the last timer
  33 *   interrupt.  Note: this must take account of any unprocessed
  34 *   timer interrupt which may be pending.
  35 */
  36struct sys_timer {
  37        struct sys_device       dev;
  38        void                    (*init)(void);
  39        void                    (*suspend)(void);
  40        void                    (*resume)(void);
  41#ifndef CONFIG_GENERIC_TIME
  42        unsigned long           (*offset)(void);
  43#endif
  44
  45#ifdef CONFIG_NO_IDLE_HZ
  46        struct dyn_tick_timer   *dyn_tick;
  47#endif
  48};
  49
  50#ifdef CONFIG_NO_IDLE_HZ
  51
  52#define DYN_TICK_ENABLED        (1 << 1)
  53
  54struct dyn_tick_timer {
  55        spinlock_t      lock;
  56        unsigned int    state;                  /* Current state */
  57        int             (*enable)(void);        /* Enables dynamic tick */
  58        int             (*disable)(void);       /* Disables dynamic tick */
  59        void            (*reprogram)(unsigned long); /* Reprograms the timer */
  60        int             (*handler)(int, void *);
  61};
  62
  63void timer_dyn_reprogram(void);
  64#else
  65#define timer_dyn_reprogram()   do { } while (0)
  66#endif
  67
  68extern struct sys_timer *system_timer;
  69extern void timer_tick(void);
  70
  71/*
  72 * Kernel time keeping support.
  73 */
  74struct timespec;
  75extern int (*set_rtc)(void);
  76extern void save_time_delta(struct timespec *delta, struct timespec *rtc);
  77extern void restore_time_delta(struct timespec *delta, struct timespec *rtc);
  78
  79#endif
  80