// $Id: router.cpp 5188 2012-08-30 00:31:31Z dub $

/*
 Copyright (c) 2007-2012, Trustees of The Leland Stanford Junior University
 All rights reserved.

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 list of conditions and the following disclaimer in the documentation and/or
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 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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 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.
*/

/*router.cpp
 *
 *The base class of either iq router or event router
 *contains a list of channels and other router configuration variables
 *
 *The older version of the simulator uses an array of flits and credit to 
 *simulate the channels. Newer version ueses flitchannel and credit channel
 *which can better model channel delay
 *
 *The older version of the simulator also uses vc_router and chaos router
 *which are replaced by iq rotuer and event router in the present form
 */

#include "booksim.hpp"
#include <iostream>
#include <cassert>
#include "router.hpp"

//////////////////Sub router types//////////////////////
#include "iq_router.hpp"
#include "event_router.hpp"
#include "chaos_router.hpp"
///////////////////////////////////////////////////////

int const Router::STALL_BUFFER_BUSY = -2;
int const Router::STALL_BUFFER_CONFLICT = -3;
int const Router::STALL_BUFFER_FULL = -4;
int const Router::STALL_BUFFER_RESERVED = -5;
int const Router::STALL_CROSSBAR_CONFLICT = -6;

Router::Router( const Configuration& config,
		Module *parent, const string & name, int id,
		int inputs, int outputs ) :
TimedModule( parent, name ), _id( id ), _inputs( inputs ), _outputs( outputs ),
   _partial_internal_cycles(0.0)
{
  _crossbar_delay   = ( config.GetInt( "st_prepare_delay" ) + 
			config.GetInt( "st_final_delay" ) );
  _credit_delay     = config.GetInt( "credit_delay" );
  _input_speedup    = config.GetInt( "input_speedup" );
  _output_speedup   = config.GetInt( "output_speedup" );
  _internal_speedup = config.GetFloat( "internal_speedup" );
  _classes          = config.GetInt( "classes" );

#ifdef TRACK_FLOWS
  _received_flits.resize(_classes, vector<int>(_inputs, 0));
  _stored_flits.resize(_classes);
  _sent_flits.resize(_classes, vector<int>(_outputs, 0));
  _active_packets.resize(_classes);
  _outstanding_credits.resize(_classes, vector<int>(_outputs, 0));
#endif

#ifdef TRACK_STALLS
  _buffer_busy_stalls.resize(_classes, 0);
  _buffer_conflict_stalls.resize(_classes, 0);
  _buffer_full_stalls.resize(_classes, 0);
  _buffer_reserved_stalls.resize(_classes, 0);
  _crossbar_conflict_stalls.resize(_classes, 0);
#endif

}

void Router::AddInputChannel( FlitChannel *channel, CreditChannel *backchannel )
{
  _input_channels.push_back( channel );
  _input_credits.push_back( backchannel );
  channel->SetSink( this, _input_channels.size() - 1 ) ;
}

void Router::AddOutputChannel( FlitChannel *channel, CreditChannel *backchannel )
{
  _output_channels.push_back( channel );
  _output_credits.push_back( backchannel );
  _channel_faults.push_back( false );
  channel->SetSource( this, _output_channels.size() - 1 ) ;
}

void Router::Evaluate( )
{
  _partial_internal_cycles += _internal_speedup;
  while( _partial_internal_cycles >= 1.0 ) {
    _InternalStep( );
    _partial_internal_cycles -= 1.0;
  }
}

void Router::OutChannelFault( int c, bool fault )
{
  assert( ( c >= 0 ) && ( (size_t)c < _channel_faults.size( ) ) );

  _channel_faults[c] = fault;
}

bool Router::IsFaultyOutput( int c ) const
{
  assert( ( c >= 0 ) && ( (size_t)c < _channel_faults.size( ) ) );

  return _channel_faults[c];
}

/*Router constructor*/
Router *Router::NewRouter( const Configuration& config,
			   Module *parent, const string & name, int id,
			   int inputs, int outputs )
{
  const string type = config.GetStr( "router" );
  Router *r = NULL;
  if ( type == "iq" ) {
    r = new IQRouter( config, parent, name, id, inputs, outputs );
  } else if ( type == "event" ) {
    r = new EventRouter( config, parent, name, id, inputs, outputs );
  } else if ( type == "chaos" ) {
    r = new ChaosRouter( config, parent, name, id, inputs, outputs );
  } else {
    cerr << "Unknown router type: " << type << endl;
  }
  /*For additional router, add another else if statement*/
  /*Original booksim specifies the router using "flow_control"
   *we now simply call these types. 
   */

  return r;
}