mame/src/emu/schedule.h

/***************************************************************************

    schedule.h

    Core device execution and scheduling engine.

****************************************************************************

    Copyright Aaron Giles
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:

        * Redistributions of source code must retain the above copyright
          notice, this list of conditions and the following disclaimer.
        * Redistributions in binary form must reproduce the above copyright
          notice, this list of conditions and the following disclaimer in
          the documentation and/or other materials provided with the
          distribution.
        * Neither the name 'MAME' nor the names of its contributors may be
          used to endorse or promote products derived from this software
          without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY AARON GILES ''AS IS'' AND ANY EXPRESS OR
    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
    WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    DISCLAIMED. IN NO EVENT SHALL AARON GILES BE LIABLE FOR ANY DIRECT,
    INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
    STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
    IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.

***************************************************************************/

#pragma once

#ifndef __EMU_H__
#error Dont include this file directly; include emu.h instead.
#endif

#ifndef __SCHEDULE_H__
#define __SCHEDULE_H__


//**************************************************************************
//  MACROS
//**************************************************************************

// macro for the RC time constant on a 74LS123 with C > 1000pF
// R is in ohms, C is in farads
#define TIME_OF_74LS123(r,c)			(0.45 * (double)(r) * (double)(c))

// macros for the RC time constant on a 555 timer IC
// R is in ohms, C is in farads
#define PERIOD_OF_555_MONOSTABLE_NSEC(r,c)	((attoseconds_t)(1100000000 * (double)(r) * (double)(c)))
#define PERIOD_OF_555_ASTABLE_NSEC(r1,r2,c)	((attoseconds_t)( 693000000 * ((double)(r1) + 2.0 * (double)(r2)) * (double)(c)))
#define PERIOD_OF_555_MONOSTABLE(r,c)		attotime::from_nsec(PERIOD_OF_555_MONOSTABLE_NSEC(r,c))
#define PERIOD_OF_555_ASTABLE(r1,r2,c)		attotime::from_nsec(PERIOD_OF_555_ASTABLE_NSEC(r1,r2,c))

#define TIMER_CALLBACK(name)			void name(running_machine &machine, void *ptr, int param)



//**************************************************************************
//  TYPE DEFINITIONS
//**************************************************************************

// timer callbacks look like this
typedef delegate<void (void *, INT32)> timer_expired_delegate;

// old-skool callbacks are like this
typedef void (*timer_expired_func)(running_machine &machine, void *ptr, INT32 param);


// ======================> emu_timer

class emu_timer
{
	friend class device_scheduler;
	friend class simple_list<emu_timer>;
	friend class fixed_allocator<emu_timer>;
	friend class resource_pool_object<emu_timer>;

	// construction/destruction
	emu_timer();
	~emu_timer();

	// allocation and re-use
	emu_timer &init(running_machine &machine, timer_expired_delegate callback, void *ptr, bool temporary);
	emu_timer &init(device_t &device, device_timer_id id, void *ptr, bool temporary);
	emu_timer &release();

public:
	// getters
	emu_timer *next() const { return m_next; }
	running_machine &machine() const { assert(m_machine != NULL); return *m_machine; }
	bool enabled() const { return m_enabled; }
	int param() const { return m_param; }
	void *ptr() const { return m_ptr; }

	// setters
	bool enable(bool enable = true);
	void set_param(int param) { m_param = param; }
	void set_ptr(void *ptr) { m_ptr = ptr; }

	// control
	void reset(attotime duration = attotime::never) { adjust(duration, m_param, m_period); }
	void adjust(attotime duration, INT32 param = 0, attotime periodicity = attotime::never);

	// timing queries
	attotime elapsed() const;
	attotime remaining() const;
	attotime start() const { return m_start; }
	attotime expire() const { return m_expire; }

private:
	// internal helpers
	void register_save();
	void schedule_next_period();
	void dump() const;

	// internal state
	running_machine *	m_machine;		// reference to the owning machine
	emu_timer *			m_next;			// next timer in order in the list
	emu_timer *			m_prev;			// previous timer in order in the list
	timer_expired_delegate m_callback;	// callback function
	INT32				m_param;		// integer parameter
	void *				m_ptr;			// pointer parameter
	bool				m_enabled;		// is the timer enabled?
	bool				m_temporary;	// is the timer temporary?
	attotime			m_period;		// the repeat frequency of the timer
	attotime			m_start;		// time when the timer was started
	attotime			m_expire;		// time when the timer will expire
	device_t *			m_device;		// for device timers, a pointer to the device
	device_timer_id		m_id;			// for device timers, the ID of the timer
};


// ======================> device_scheduler

class device_scheduler
{
	friend class device_execute_interface;
	friend class emu_timer;

public:
	// construction/destruction
	device_scheduler(running_machine &machine);
	~device_scheduler();

	// getters
	running_machine &machine() const { return m_machine; }
	attotime time() const;
	emu_timer *first_timer() const { return m_timer_list; }
	device_execute_interface *currently_executing() const { return m_executing_device; }
	bool can_save() const;

	// execution
	void timeslice();
	void abort_timeslice();
	void trigger(int trigid, attotime after = attotime::zero);
	void boost_interleave(attotime timeslice_time, attotime boost_duration);
	void make_active() { m_cothread.make_active(); }

	// timers, specified by callback/name
	emu_timer *timer_alloc(timer_expired_delegate callback, void *ptr = NULL);
	void timer_set(attotime duration, timer_expired_delegate callback, int param = 0, void *ptr = NULL);
	void timer_pulse(attotime period, timer_expired_delegate callback, int param = 0, void *ptr = NULL);
	void synchronize(timer_expired_delegate callback = timer_expired_delegate(), int param = 0, void *ptr = NULL) { timer_set(attotime::zero, callback, param, ptr); }

	// timers with old-skool callbacks
	emu_timer *timer_alloc(timer_expired_func callback, const char *name, void *ptr = NULL) { return timer_alloc(timer_expired_delegate(callback, name, &machine()), ptr); }
	void timer_set(attotime duration, timer_expired_func callback, const char *name, int param = 0, void *ptr = NULL) { timer_set(duration, timer_expired_delegate(callback, name, &machine()), param, ptr); }
	void timer_pulse(attotime period, timer_expired_func callback, const char *name, int param = 0, void *ptr = NULL) { timer_pulse(period, timer_expired_delegate(callback, name, &machine()), param, ptr); }
	void synchronize(timer_expired_func callback, const char *name = NULL, int param = 0, void *ptr = NULL) { timer_set(attotime::zero, callback, name, param, ptr); }

	// timers, specified by device/id; generally devices should use the device_t methods instead
	emu_timer *timer_alloc(device_t &device, device_timer_id id = 0, void *ptr = NULL);
	void timer_set(attotime duration, device_t &device, device_timer_id id = 0, int param = 0, void *ptr = NULL);

	// debugging
	void dump_timers() const;

	// for emergencies only!
	void eat_all_cycles();

private:
	// callbacks
	void timed_trigger(void *ptr, INT32 param);
	void presave();
	void postload();

	// scheduling helpers
	void compute_perfect_interleave();
	void rebuild_execute_list();
	void add_scheduling_quantum(attotime quantum, attotime duration);

	// timer helpers
	emu_timer &timer_list_insert(emu_timer &timer);
	emu_timer &timer_list_remove(emu_timer &timer);
	void execute_timers();

	// internal state
	running_machine &			m_machine;					// reference to our machine
	device_execute_interface *	m_executing_device;			// pointer to currently executing device
	device_execute_interface *	m_execute_list;				// list of devices to be executed
	attotime					m_basetime;					// global basetime; everything moves forward from here
	cothread					m_cothread;					// core scheduler thread

	// list of active timers
	emu_timer *					m_timer_list;				// head of the active list
	fixed_allocator<emu_timer>	m_timer_allocator;			// allocator for timers

	// other internal states
	emu_timer *					m_callback_timer;			// pointer to the current callback timer
	bool						m_callback_timer_modified;	// true if the current callback timer was modified
	attotime					m_callback_timer_expire_time; // the original expiration time

	// scheduling quanta
	class quantum_slot
	{
		friend class simple_list<quantum_slot>;

	public:
		quantum_slot *next() const { return m_next; }

		quantum_slot *			m_next;
		attoseconds_t			m_actual;					// actual duration of the quantum
		attoseconds_t			m_requested;				// duration of the requested quantum
		attotime				m_expire;					// absolute expiration time of this quantum
	};
	simple_list<quantum_slot>	m_quantum_list;				// list of active quanta
	fixed_allocator<quantum_slot> m_quantum_allocator;		// allocator for quanta
	attoseconds_t				m_quantum_minimum;			// duration of minimum quantum
};


#endif	// __SCHEDULE_H__ */