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  */
  36 struct sys_timer {
  37         struct sys_device       dev;
  38         void                    (*init)(void);
  39         void                    (*suspend)(void);
  40         void                    (*resume)(void);
  41         unsigned long           (*offset)(void);
  42
  43 #ifdef CONFIG_NO_IDLE_HZ
  44         struct dyn_tick_timer   *dyn_tick;
  45 #endif
  46 };
  47
  48 #ifdef CONFIG_NO_IDLE_HZ
  49
  50 #define DYN_TICK_ENABLED        (1 << 1)
  51
  52 struct dyn_tick_timer {
  53         unsigned int    state;                  /* Current state */
  54         int             (*enable)(void);        /* Enables dynamic tick */
  55         int             (*disable)(void);       /* Disables dynamic tick */
  56         void            (*reprogram)(unsigned long); /* Reprograms the timer */
  57         int             (*handler)(int, void *, struct pt_regs *);
  58 };
  59
  60 void timer_dyn_reprogram(void);
  61 #else
  62 #define timer_dyn_reprogram()   do { } while (0)
  63 #endif
  64
  65 extern struct sys_timer *system_timer;
  66 extern void timer_tick(struct pt_regs *);
  67
  68 /*
  69  * Kernel time keeping support.
  70  */
  71 extern int (*set_rtc)(void);
  72 extern void save_time_delta(struct timespec *delta, struct timespec *rtc);
  73 extern void restore_time_delta(struct timespec *delta, struct timespec *rtc);
  74
  75 #endif