/* SPDX-License-Identifier: GPL-2.0 */

  #ifndef _TICK_SCHED_H
  #define _TICK_SCHED_H
  
  #include <linux/hrtimer.h>

  enum tick_device_mode {
  	TICKDEV_MODE_PERIODIC,
  	TICKDEV_MODE_ONESHOT,
  };
  
  struct tick_device {
  	struct clock_event_device *evtdev;
  	enum tick_device_mode mode;
  };

  enum tick_nohz_mode {
  	NOHZ_MODE_INACTIVE,
  	NOHZ_MODE_LOWRES,
  	NOHZ_MODE_HIGHRES,
  };
  
  /**
   * struct tick_sched - sched tick emulation and no idle tick control/stats
   * @sched_timer:	hrtimer to schedule the periodic tick in high
   *			resolution mode

   * @check_clocks:	Notification mechanism about clocksource changes
   * @nohz_mode:		Mode - one state of tick_nohz_mode
   * @inidle:		Indicator that the CPU is in the tick idle mode
   * @tick_stopped:	Indicator that the idle tick has been stopped
   * @idle_active:	Indicator that the CPU is actively in the tick idle mode;
   *			it is resetted during irq handling phases.
   * @do_timer_lst:	CPU was the last one doing do_timer before going idle
   * @got_idle_tick:	Tick timer function has run with @inidle set

   * @last_tick:		Store the last tick expiry time when the tick
   *			timer is modified for nohz sleeps. This is necessary
   *			to resume the tick timer operation in the timeline
   *			when the CPU returns from nohz sleep.

   * @next_tick:		Next tick to be fired when in dynticks mode.

   * @idle_jiffies:	jiffies at the entry to idle for idle time accounting
   * @idle_calls:		Total number of idle calls
   * @idle_sleeps:	Number of idle calls, where the sched tick was stopped
   * @idle_entrytime:	Time when the idle call was entered
   * @idle_waketime:	Time when the idle was interrupted
   * @idle_exittime:	Time when the idle state was left
   * @idle_sleeptime:	Sum of the time slept in idle with sched tick stopped
   * @iowait_sleeptime:	Sum of the time slept in idle with sched tick stopped, with IO outstanding

   * @timer_expires:	Anticipated timer expiration time (in case sched tick is stopped)
   * @timer_expires_base:	Base time clock monotonic for @timer_expires

   * @next_timer:		Expiry time of next expiring timer for debugging purpose only
   * @tick_dep_mask:	Tick dependency mask - is set, if someone needs the tick

   */
  struct tick_sched {
  	struct hrtimer			sched_timer;
  	unsigned long			check_clocks;
  	enum tick_nohz_mode		nohz_mode;

  
  	unsigned int			inidle		: 1;
  	unsigned int			tick_stopped	: 1;
  	unsigned int			idle_active	: 1;
  	unsigned int			do_timer_last	: 1;
  	unsigned int			got_idle_tick	: 1;

  	ktime_t				last_tick;

  	ktime_t				next_tick;

  	unsigned long			idle_jiffies;
  	unsigned long			idle_calls;
  	unsigned long			idle_sleeps;

  	ktime_t				idle_entrytime;
  	ktime_t				idle_waketime;
  	ktime_t				idle_exittime;
  	ktime_t				idle_sleeptime;
  	ktime_t				iowait_sleeptime;

  	unsigned long			last_jiffies;

  	u64				timer_expires;
  	u64				timer_expires_base;

  	u64				next_timer;

  	ktime_t				idle_expires;

  	atomic_t			tick_dep_mask;

  };
  
  extern struct tick_sched *tick_get_tick_sched(int cpu);
  
  extern void tick_setup_sched_timer(void);
  #if defined CONFIG_NO_HZ_COMMON || defined CONFIG_HIGH_RES_TIMERS
  extern void tick_cancel_sched_timer(int cpu);
  #else
  static inline void tick_cancel_sched_timer(int cpu) { }
  #endif

  #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
  extern int __tick_broadcast_oneshot_control(enum tick_broadcast_state state);
  #else
  static inline int
  __tick_broadcast_oneshot_control(enum tick_broadcast_state state)
  {
  	return -EBUSY;
  }
  #endif

  #endif