/////////////////////////////////////////////////////////////////////////
// $Id: pit_wrap.cc,v 1.15 2002-02-08 02:57:27 yakovlev Exp $
/////////////////////////////////////////////////////////////////////////
//
//  Copyright (C) 2002  MandrakeSoft S.A.
//
//    MandrakeSoft S.A.
//    43, rue d'Aboukir
//    75002 Paris - France
//    http://www.linux-mandrake.com/
//    http://www.mandrakesoft.com/
//
//  This library is free software; you can redistribute it and/or
//  modify it under the terms of the GNU Lesser General Public
//  License as published by the Free Software Foundation; either
//  version 2 of the License, or (at your option) any later version.
//
//  This library is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
//  Lesser General Public License for more details.
//
//  You should have received a copy of the GNU Lesser General Public
//  License along with this library; if not, write to the Free Software
//  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA



#include "bochs.h"

#if BX_USE_NEW_PIT

#include "pit_wrap.h"
#define LOG_THIS bx_pit.

bx_pit_c bx_pit;
#if BX_USE_PIT_SMF
#define this (&bx_pit)
#endif

#ifdef OUT
#  undef OUT
#endif

#define TIME_DIVIDER (1)
#define TIME_MULTIPLIER (1)
#define TIME_HEADSTART (1)
//USEC_ALPHA is multiplier for the past.
//USEC_ALPHA_B is 1-USEC_ALPHA, or multiplier for the present.
#define USEC_ALPHA (.8)
#define USEC_ALPHA_B (.2)

//How many timer ticks per usecond.
//1.193181MHz Clock
//1193/1000 Ticks Per usecond.
#define TICKS_PER_SECOND (1193181)
#define USEC_PER_SECOND (1000000)
#define TIME_MULT 1.193
#if BX_USE_REALTIME_PIT
#  define TICKS_TO_USEC(a) ( ((a)*BX_PIT_THIS s.usec_per_second)/BX_PIT_THIS s.ticks_per_second )
#  define USEC_TO_TICKS(a) ( ((a)*BX_PIT_THIS s.ticks_per_second)/BX_PIT_THIS s.usec_per_second )
#else
#  define TICKS_TO_USEC(a) ( ((a)*USEC_PER_SECOND)/TICKS_PER_SECOND )
#  define USEC_TO_TICKS(a) ( ((a)*TICKS_PER_SECOND)/USEC_PER_SECOND )
#endif
#define MAX(a,b) ( ((a)>(b))?(a):(b) )

bx_pit_c::bx_pit_c( void )
{
  put("PIT");
  settype(PITLOG);
  s.speaker_data_on=0;

  /* 8254 PIT (Programmable Interval Timer) */

  BX_PIT_THIS s.timer_handle[1] = BX_NULL_TIMER_HANDLE;
  BX_PIT_THIS s.timer_handle[2] = BX_NULL_TIMER_HANDLE;
  BX_PIT_THIS s.timer_handle[0] = BX_NULL_TIMER_HANDLE;
}

bx_pit_c::~bx_pit_c( void )
{
}

  int
bx_pit_c::init( bx_devices_c *d )
{
  BX_PIT_THIS devices = d;

  BX_PIT_THIS devices->register_irq(0, "8254 PIT");
  BX_PIT_THIS devices->register_io_read_handler(this, read_handler, 0x0040, "8254 PIT");
  BX_PIT_THIS devices->register_io_read_handler(this, read_handler, 0x0041, "8254 PIT");
  BX_PIT_THIS devices->register_io_read_handler(this, read_handler, 0x0042, "8254 PIT");
  BX_PIT_THIS devices->register_io_read_handler(this, read_handler, 0x0043, "8254 PIT");
  BX_PIT_THIS devices->register_io_read_handler(this, read_handler, 0x0061, "8254 PIT");

  BX_PIT_THIS devices->register_io_write_handler(this, write_handler, 0x0040, "8254 PIT");
  BX_PIT_THIS devices->register_io_write_handler(this, write_handler, 0x0041, "8254 PIT");
  BX_PIT_THIS devices->register_io_write_handler(this, write_handler, 0x0042, "8254 PIT");
  BX_PIT_THIS devices->register_io_write_handler(this, write_handler, 0x0043, "8254 PIT");
  BX_PIT_THIS devices->register_io_write_handler(this, write_handler, 0x0061, "8254 PIT");

  BX_DEBUG(("pit: starting init"));

  BX_PIT_THIS s.speaker_data_on = 0;
  BX_PIT_THIS s.refresh_clock_div2 = 0;

  BX_PIT_THIS s.timer.init();

  BX_PIT_THIS s.timer_handle[0] = bx_pc_system.register_timer(this, timer_handler, (unsigned) 100 , 1, 1);
  BX_DEBUG(("pit: RESETting timer."));
  bx_pc_system.deactivate_timer(BX_PIT_THIS s.timer_handle[0]);
  BX_DEBUG(("deactivated timer."));
  if(BX_PIT_THIS s.timer.get_next_event_time()) {
    bx_pc_system.activate_timer(BX_PIT_THIS s.timer_handle[0], 
				MAX(1,TICKS_TO_USEC(BX_PIT_THIS s.timer.get_next_event_time())),
				0);
    BX_DEBUG(("activated timer."));
  }
  BX_PIT_THIS s.last_next_event_time = BX_PIT_THIS s.timer.get_next_event_time();
  BX_PIT_THIS s.last_usec=bx_pc_system.time_usec();

  BX_PIT_THIS s.total_ticks=0;

#if BX_USE_REALTIME_PIT
  BX_PIT_THIS s.usec_per_second=USEC_PER_SECOND;
  BX_PIT_THIS s.ticks_per_second=TICKS_PER_SECOND;
  BX_PIT_THIS s.total_sec=0;
  BX_PIT_THIS s.last_time=(time(NULL)*TIME_MULTIPLIER/TIME_DIVIDER)+TIME_HEADSTART;
#else
  BX_PIT_THIS s.total_usec=0;
#endif

  BX_DEBUG(("pit: finished init"));

  BX_DEBUG(("s.last_usec=%d",BX_PIT_THIS s.last_usec));
  BX_DEBUG(("s.timer_id=%d",BX_PIT_THIS s.timer_handle[0]));
  BX_DEBUG(("s.timer.get_next_event_time=%d",BX_PIT_THIS s.timer.get_next_event_time()));
  BX_DEBUG(("s.last_next_event_time=%d",BX_PIT_THIS s.last_next_event_time));

  return(1);
}


void
bx_pit_c::timer_handler(void *this_ptr) {
  bx_pit_c * class_ptr = (bx_pit_c *) this_ptr;

  class_ptr->handle_timer();
}

void
bx_pit_c::handle_timer() {
  Bit64u time_passed = bx_pc_system.time_usec()-BX_PIT_THIS s.last_usec;
  Bit32u time_passed32 = time_passed;

  BX_DEBUG(("pit: entering timer handler"));

  if(time_passed32) {
    periodic(time_passed32);
  }
  BX_PIT_THIS s.last_usec=BX_PIT_THIS s.last_usec + time_passed;
  if(time_passed ||
     (BX_PIT_THIS s.last_next_event_time
      != BX_PIT_THIS s.timer.get_next_event_time())
     ) {
    BX_DEBUG(("pit: RESETting timer."));
    bx_pc_system.deactivate_timer(BX_PIT_THIS s.timer_handle[0]);
    BX_DEBUG(("deactivated timer."));
    if(BX_PIT_THIS s.timer.get_next_event_time()) {
      bx_pc_system.activate_timer(BX_PIT_THIS s.timer_handle[0], 
				  MAX(1,TICKS_TO_USEC(BX_PIT_THIS s.timer.get_next_event_time())),
				  0);
      BX_DEBUG(("activated timer."));
    }
    BX_PIT_THIS s.last_next_event_time = BX_PIT_THIS s.timer.get_next_event_time();
  }
  BX_DEBUG(("s.last_usec=%d",BX_PIT_THIS s.last_usec));
  BX_DEBUG(("s.timer_id=%d",BX_PIT_THIS s.timer_handle[0]));
  BX_DEBUG(("s.timer.get_next_event_time=%x",BX_PIT_THIS s.timer.get_next_event_time()));
  BX_DEBUG(("s.last_next_event_time=%d",BX_PIT_THIS s.last_next_event_time));
}


  // static IO port read callback handler
  // redirects to non-static class handler to avoid virtual functions

  Bit32u
bx_pit_c::read_handler(void *this_ptr, Bit32u address, unsigned io_len)
{
#if !BX_USE_PIT_SMF
  bx_pit_c *class_ptr = (bx_pit_c *) this_ptr;

  return( class_ptr->read(address, io_len) );
}


  Bit32u
bx_pit_c::read( Bit32u   address, unsigned int io_len )
{
#else
  UNUSED(this_ptr);
#endif  // !BX_USE_PIT_SMF
  BX_DEBUG(("pit: entering read handler"));

  handle_timer();

  if (io_len > 1)
    BX_PANIC(("pit: io read from port %04x, len=%u", (unsigned) address,
             (unsigned) io_len));

  if (bx_dbg.pit)
    BX_INFO(("pit: io read from port %04x", (unsigned) address));

  switch (address) {

    case 0x40: /* timer 0 - system ticks */
      return(BX_PIT_THIS s.timer.read(0));
      break;
    case 0x41: /* timer 1 read */
      return(BX_PIT_THIS s.timer.read(1));
      break;
    case 0x42: /* timer 2 read */
      return(BX_PIT_THIS s.timer.read(2));
      break;
    case 0x43: /* timer 1 read */
      return(BX_PIT_THIS s.timer.read(3));
      break;

    case 0x61:
      /* AT, port 61h */
      BX_PIT_THIS s.refresh_clock_div2 = !BX_PIT_THIS s.refresh_clock_div2;
      return( (BX_PIT_THIS s.timer.read_OUT(2)<<5) |
              (BX_PIT_THIS s.refresh_clock_div2<<4) |
              (BX_PIT_THIS s.speaker_data_on<<1) |
              (BX_PIT_THIS s.timer.read_GATE(2)?1:0) );
      break;

    default:
      BX_PANIC(("pit: unsupported io read from port %04x", address));
  }
  return(0); /* keep compiler happy */
}


  // static IO port write callback handler
  // redirects to non-static class handler to avoid virtual functions

  void
bx_pit_c::write_handler(void *this_ptr, Bit32u address, Bit32u dvalue, unsigned io_len)
{
#if !BX_USE_PIT_SMF
  bx_pit_c *class_ptr = (bx_pit_c *) this_ptr;

  class_ptr->write(address, dvalue, io_len);
}

  void
bx_pit_c::write( Bit32u   address, Bit32u   dvalue,
                unsigned int io_len )
{
#else
  UNUSED(this_ptr);
#endif  // !BX_USE_PIT_SMF
  Bit8u   value;
  Bit64u time_passed = bx_pc_system.time_usec()-BX_PIT_THIS s.last_usec;
  Bit32u time_passed32 = time_passed;

  BX_DEBUG(("pit: entering write handler"));

  if(time_passed32) {
    periodic(time_passed32);
  }
  BX_PIT_THIS s.last_usec=BX_PIT_THIS s.last_usec + time_passed;

  value = (Bit8u  ) dvalue;

  if (io_len > 1)
    BX_PANIC(("pit: io write to port %04x, len=%u", (unsigned) address,
             (unsigned) io_len));

  if (bx_dbg.pit)
    BX_INFO(("pit: write to port %04x = %02x",
      (unsigned) address, (unsigned) value));

  switch (address) {
    case 0x40: /* timer 0: write count register */
      BX_PIT_THIS s.timer.write(0,value);
      break;

    case 0x41: /* timer 1: write count register */
      BX_PIT_THIS s.timer.write( 1,value );
      break;

    case 0x42: /* timer 2: write count register */
      BX_PIT_THIS s.timer.write( 2,value );
      break;

    case 0x43: /* timer 0-2 mode control */
      BX_PIT_THIS s.timer.write( 3,value );
      break;

    case 0x61:
      BX_PIT_THIS s.speaker_data_on = (value >> 1) & 0x01;
/*??? only on AT+ */
      BX_PIT_THIS s.timer.set_GATE(2, value & 0x01);
#if BX_CPU_LEVEL < 2
      /* ??? XT: */
      bx_kbd_port61h_write(value);
#endif
      break;

    default:
      BX_PANIC(("pit: unsupported io write to port %04x = %02x",
        (unsigned) address, (unsigned) value));
  }

  if ((BX_PIT_THIS s.timer.read_OUT(0))==1) {
    bx_pic.raise_irq(0);
  } else {
    bx_pic.lower_irq(0);
  }

  if(time_passed ||
     (BX_PIT_THIS s.last_next_event_time
      != BX_PIT_THIS s.timer.get_next_event_time())
     ) {
    BX_DEBUG(("pit: RESETting timer."));
    bx_pc_system.deactivate_timer(BX_PIT_THIS s.timer_handle[0]);
    BX_DEBUG(("deactivated timer."));
    if(BX_PIT_THIS s.timer.get_next_event_time()) {
      bx_pc_system.activate_timer(BX_PIT_THIS s.timer_handle[0], 
				  MAX(1,TICKS_TO_USEC(BX_PIT_THIS s.timer.get_next_event_time())),
				  0);
      BX_DEBUG(("activated timer."));
    }
    BX_PIT_THIS s.last_next_event_time = BX_PIT_THIS s.timer.get_next_event_time();
  }
  BX_DEBUG(("s.last_usec=%d",BX_PIT_THIS s.last_usec));
  BX_DEBUG(("s.timer_id=%d",BX_PIT_THIS s.timer_handle[0]));
  BX_DEBUG(("s.timer.get_next_event_time=%x",BX_PIT_THIS s.timer.get_next_event_time()));
  BX_DEBUG(("s.last_next_event_time=%d",BX_PIT_THIS s.last_next_event_time));

}




  int
bx_pit_c::SaveState( class state_file *fd )
{
  fd->write_check ("8254 start");
  fd->write (&BX_PIT_THIS s, sizeof (BX_PIT_THIS s));
  fd->write_check ("8254 end");
  return(0);
}


  int
bx_pit_c::LoadState( class state_file *fd )
{
  fd->read_check ("8254 start");
  fd->read (&BX_PIT_THIS s, sizeof (BX_PIT_THIS s));
  fd->read_check ("8254 end");
  return(0);
}


#if 0
  void
bx_kbd_port61h_write(Bit8u   value)
{
//  PcError("KBD_PORT61H_WRITE(): not implemented yet");
  UNUSED( value );
}
#endif


  Boolean
bx_pit_c::periodic( Bit32u   usec_delta )
{
  Boolean prev_timer0_out = BX_PIT_THIS s.timer.read_OUT(0);
  Boolean want_interrupt = 0;
  Bit32u ticks_delta = 0;

#if BX_USE_REALTIME_PIT
  ticks_delta=(Bit32u)(USEC_TO_TICKS(usec_delta));
  BX_PIT_THIS s.total_ticks += ticks_delta;
  second_update_data();
#else
  BX_PIT_THIS s.total_usec += usec_delta;
  ticks_delta=(Bit32u)((USEC_TO_TICKS((Bit64u)(BX_PIT_THIS s.total_usec)))-BX_PIT_THIS s.total_ticks);
  BX_PIT_THIS s.total_ticks += ticks_delta;

  while ((BX_PIT_THIS s.total_ticks >= 1193181) && (BX_PIT_THIS s.total_usec >= 1000000)) {
    BX_PIT_THIS s.total_ticks -= 1193181;
    BX_PIT_THIS s.total_usec  -= 1000000;
  }
#endif

  while(ticks_delta>0) {
    Bit32u maxchange=BX_PIT_THIS s.timer.get_next_event_time();
    Bit32u timedelta=maxchange;
    if((maxchange==0) || (maxchange>ticks_delta)) {
      timedelta=ticks_delta;
    }
    BX_PIT_THIS s.timer.clock_all(timedelta);
    if ( (prev_timer0_out==0) ) {
      if ((BX_PIT_THIS s.timer.read_OUT(0))==1) {
        bx_pic.raise_irq(0);
        prev_timer0_out=1;
      }
    } else {
      if ((BX_PIT_THIS s.timer.read_OUT(0))==0) {
        bx_pic.lower_irq(0);
        prev_timer0_out=0;
      }
    }
    prev_timer0_out=BX_PIT_THIS s.timer.read_OUT(0);
    ticks_delta-=timedelta;
  }

  return(want_interrupt);
}


#if BX_USE_REALTIME_PIT
void
bx_pit_c::second_update_data(void) {
  Bit64u timediff=(time(NULL)*TIME_MULTIPLIER/TIME_DIVIDER)-BX_PIT_THIS s.last_time;
  BX_PIT_THIS s.last_time += timediff;
  if(timediff) {
    Bit64s tickstemp;

    BX_PIT_THIS s.total_sec += timediff;

    if(timediff==1) printf("1\n");

    printf("timediff: %lld, total_sec: %lld, total_ticks: %lld\n",timediff, BX_PIT_THIS s.total_sec, BX_PIT_THIS s.total_ticks);

    tickstemp = 
      (((BX_PIT_THIS s.total_sec)*TICKS_PER_SECOND)-BX_PIT_THIS s.total_ticks)
       + TICKS_PER_SECOND;

//    while((BX_PIT_THIS s.total_sec >= 0) && (BX_PIT_THIS s.total_ticks >= TICKS_PER_SECOND)) {
//      BX_PIT_THIS s.total_sec -= 1;
//      BX_PIT_THIS s.total_ticks -= TICKS_PER_SECOND;
//    }

    if(tickstemp > (TICKS_PER_SECOND*1.5)) {
      printf("Running WAY too slow. tps:%lld\n",tickstemp);
      tickstemp = TICKS_PER_SECOND*1.5;
      printf("..................... tps:%lld\n",tickstemp);
    } else if(tickstemp < (TICKS_PER_SECOND*0.5)) {
      printf("Running WAY too fast. tps:%lld\n",tickstemp);
      tickstemp = TICKS_PER_SECOND*0.5;
      printf("..................... tps:%lld\n",tickstemp);
    }

    BX_PIT_THIS s.ticks_per_second = tickstemp;

    BX_PIT_THIS s.usec_per_second = ((bx_pc_system.time_usec()-BX_PIT_THIS s.last_sec_usec)/timediff)*USEC_ALPHA_B + USEC_ALPHA*BX_PIT_THIS s.usec_per_second;
    BX_PIT_THIS s.last_sec_usec = bx_pc_system.time_usec();
    printf("Parms: ticks_per_second=%lld, usec_per_second=%lld\n",BX_PIT_THIS s.ticks_per_second, BX_PIT_THIS s.usec_per_second);
  }
}
#endif // #if BX_USE_REALTIME_PIT
#endif // #if BX_USE_NEW_PIT