at_initiator_explicit.cpp

SystemC Transaction Level Modelling. 是基于SystemC之上的总线互联协议

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//=============================================================================
///  @file at_initiator_explicit.cpp
///  @Details Implements a AT non-blocking initiator 
//
//=============================================================================
//  Original Authors:
//    Bill Bunton, ESLX
//    Charles Wilson, ESLX
//    Anna Keist, ESLX
//=============================================================================

#include "reporting.h"                                // Reporting convenience macros
#include "at_initiator_explicit.h"                    // Our header
#include "tlm.h"                                      // TLM headers

using namespace sc_core;

static const char *filename = "at_initiator_explicit.cpp";  ///  filename for reporting

//=============================================================================
///Constructor

at_initiator_explicit::at_initiator_explicit        // constructor
( sc_module_name name                               // module name
, const unsigned int ID                             // initiator ID
, sc_core::sc_time end_rsp_delay                    // delay
)
: sc_module           (name)                        /// init module name
, initiator_socket    ("initiator_socket")          /// init socket name
, m_send_end_rsp_PEQ  ("send_end_rsp_PEQ")          /// init PEQ name  
, m_ID            (ID)                              /// init initiator ID
, m_end_rsp_delay (end_rsp_delay)                   /// init end response delay

{ 
  // bind initiator to the export
  initiator_socket (*this);                     

  // register thread process
  SC_THREAD(initiator_thread);                  

  // register method process
  SC_METHOD(send_end_rsp_method);
               
    sensitive << m_send_end_rsp_PEQ.get_event();
    dont_initialize();
}

//=============================================================================
//
//  Initiator thread
//
//=============================================================================
void at_initiator_explicit::initiator_thread(void)  // initiator thread
{  
  tlm::tlm_generic_payload *transaction_ptr;        // transaction pointer
  std::ostringstream       msg;                     // log message

  while (true) 
  {
//=============================================================================
// Read FIFO to Get new transaction GP from the traffic generator 
//=============================================================================
    transaction_ptr = request_in_port->read();  // get request from input fifo
  
    tlm::tlm_phase phase  = tlm::BEGIN_REQ;     // Create phase objects 
    sc_time delay         = SC_ZERO_TIME;       // Create delay objects 

    msg.str("");
    msg << "Initiator: " << m_ID 
        << " starting new transaction" 
        << endl << "      " 
        << "Initiator: " << m_ID               
        << " nb_transport_fw (GP, " 
        << report::print(phase) << ", "
        << delay << ")";
    REPORT_INFO(filename,  __FUNCTION__, msg.str());


//-----------------------------------------------------------------------------
// Make the non-blocking call and decode returned status (tlm_sync_enum) 
//-----------------------------------------------------------------------------
    tlm::tlm_sync_enum 
    return_value = initiator_socket->nb_transport_fw(*transaction_ptr, phase, delay);
    
    msg.str("");
    msg << "Initiator: " << m_ID
      << " " << report::print(return_value) <<  " (GP, "
      << report::print(phase) << ", "
      << delay << ")" << endl; 

    switch (return_value) {
//-----------------------------------------------------------------------------
//  The target returned COMPLETED this is a 1 phase transaction 
//    Wait the annotated delay
//    Return the transaction to the traffic generator 
//    Make the next request 
//-----------------------------------------------------------------------------
      case tlm::TLM_COMPLETED: 
      {
        wait(delay + m_end_rsp_delay);              // wait the annotated delay 

        msg << "      "
          << "Initiator: " << m_ID
          << " target returned COMPLETED with annotated time ";
        REPORT_INFO (filename, __FUNCTION__, msg.str() );

        response_out_port->write(transaction_ptr);  // return txn to traffic gen

        break;
      }// end case TLM_COMPLETED

//-----------------------------------------------------------------------------
// Target returned UPDATED  
//-----------------------------------------------------------------------------
      case tlm::TLM_UPDATED: 
      {
//-----------------------------------------------------------------------------
//  Put poiter in waiting backware path map
//    Wait the annotated delay
//    Make the next request 
//-----------------------------------------------------------------------------
      if( phase == tlm::END_REQ) {

          m_waiting_bw_path_map.insert(make_pair(transaction_ptr
                                                  ,Rcved_END_REQ_enum
                                                  )); 
         
          wait(delay);                    // wait the annotated delay 
            
          msg << "      "
              << "Initiator: " << m_ID
              << " transaction waiting begin-response on backward path"; 
          REPORT_INFO (filename, __FUNCTION__, msg.str() );
        }
        
//-----------------------------------------------------------------------------
//    Wait the annotated delay
//    Use payload event queue to schedule sending end response  
//    Make the next request 
//-----------------------------------------------------------------------------

        else if( phase == tlm::BEGIN_RESP) {
          msg << "      "
              << "Initiator: " << m_ID 
              << " transaction moved to send-end-response PEQ "
              << endl;

          wait(delay);                    // wait the annotated delay 
          
          m_send_end_rsp_PEQ.notify (*transaction_ptr, m_end_rsp_delay);

          msg << "      "
              << "Initiator: " << m_ID
              << " "  <<  " (GP, "
              << report::print(phase) << ", "
              << delay << ")" ; 
          REPORT_INFO (filename, __FUNCTION__, msg.str() )
        }
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
        else {
          msg << "      "
          << "Initiator: " << m_ID
          << " Unexpected phase for UPDATED return from target ";
          REPORT_FATAL (filename, __FUNCTION__, msg.str() );
        }
        break;
      } // end case TLM_UPDATED


//-----------------------------------------------------------------------------
//  Target returned ACCEPTED this an explicit response 
//    Add the transaction pointer to the waiting backward path map  
//    END REQUEST RULE  wait for the target to response
//-----------------------------------------------------------------------------
      case tlm::TLM_ACCEPTED:
      {
        msg << "      "
        << "Initiator: " << m_ID 
        << " transaction waiting end-request on backward-path ";
        REPORT_INFO (filename, __FUNCTION__, msg.str() );
        
        //  use map to track transaction including current state information 
        m_waiting_bw_path_map.insert (make_pair (transaction_ptr
                                                ,Rcved_ACCEPTED_enum
                                                ));  
                                                
        wait (m_enable_next_request_event);   // wait for the target to response                                  
      
        break;
      } // end case TLM_ACCEPTED


//-----------------------------------------------------------------------------
// All case covered default 
//-----------------------------------------------------------------------------
      default:
      {
        msg << "      "
        << "Initiator: " << m_ID 
        << " Unexpected response to BEGIN_REQ ";
        REPORT_FATAL (filename, __FUNCTION__, msg.str() );
        break;
      }
    } // end case
  } // end while true
} // end initiator_thread 



//=============================================================================
///  @fn at_initiator_explicit::nb_transport_bw
//
///  @brief non-blocking transport from targets