Tlm/systemc: TLM socket binding problem

stay systemc Programming , If the program run The following two types of errors occur during the process , It means that there is port Not properly bound .

Error:  (E126) sc_export instance already bound: xxxxxx

In file: xxxx/sysc/sysc/communication/sc_export.h:188 (systemc 2.3.3)

In file: xxxx/sysc/sysc/communication/sc_export.h:179 (systemc 2.3.1)

 

Error: (E120) sc_export instance has no interface: init.init_socket_export_0

In file: xxxxx/sysc/communication/sc_export.h:174 (systemc 2.3.3)

In file: xxxxx/sysc/communication/sc_export.h:166 (systemc 2.3.1)

see systemC spec, Find out port Binding does have some limitations ,16.1.1.2 The following sections describe .

meanwhile , stay 13.1 chapter P462 There are the following binding examples . In this example , because Initiator and Target Class tlm socket, so struct Parent_of_initiator When binding in ,initiator->init_socket.bind( init_socket ); Or you could write it as init_socket.bind(initiator->init_socket). but If Initiator Class defines simple socket, Must use the... In the above table bind The way .

Here is an example written by myself , And give the wrong way of writing

// execute:    
//     g++ -g -Wall -lsystemc -m64 -pthread main.cpp  
//         -L/$(your systemc path)/lib-linux64 
//         -I/$(your systemc path)/include  -I/$(your systemc path)/src/tlm_utils -o sim

#include <systemc>
#include "tlm.h"
#include "tlm_utils/simple_initiator_socket.h"
#include "tlm_utils/simple_target_socket.h"

using namespace sc_core;
using namespace std;

//Initiator
class Initiator : public sc_core::sc_module {
 public:
  tlm_utils::simple_initiator_socket<Initiator> init_socket;
  SC_HAS_PROCESS(Initiator);
  explicit Initiator(sc_core::sc_module_name name);
  ~Initiator() override = default;
};

Initiator::Initiator(sc_core::sc_module_name name)
  : sc_core::sc_module(name), init_socket("dummy_initiator_socket") {}

//Target
class Target : public sc_core::sc_module {
 public:
  tlm_utils::simple_target_socket<Target> targ_socket;

  SC_HAS_PROCESS(Target);
  explicit Target(sc_core::sc_module_name name);
  ~Target() override = default;
};

Target::Target(sc_core::sc_module_name name)
  : sc_core::sc_module(name), targ_socket("dummy_target_socket") {}

// Parent of initiator
struct Parent_of_initiator: sc_module // Showing hierarchical socket binding
{
  // here can't use simple socket, will lead to simulation error  
  //     (E126) sc_export instance already bound:xxxxxxxxx
  // tlm_utils::simple_initiator_socket<Initiator> init_socket; //error use  
  tlm::tlm_initiator_socket<32> init_socket;

  Initiator* initiator;
  SC_CTOR(Parent_of_initiator) : init_socket("init_socket") {
    initiator = new Initiator("initiator");

    // here MUST use  simple init socket.bind(tlm init socket)
    // if use   tlm init socket.bind (simple init socket)  may lead to simulation error
    //        Error: (E120) sc_export instance has no interface: xxxxxxx
    // init_socket(initiator->init_socket);  //error use
    initiator->init_socket.bind( init_socket ); // Bind initiator socket to parent initiator socket
  }
};

// Parent of target
struct Parent_of_target: sc_module
{
  // here can't use simple socket, will lead to simulation error  
  //     (E126) sc_export instance already bound:xxxxxxxxx
  // tlm_utils::simple_target_socket<Initiator> targ_socket; //error use  
  tlm::tlm_target_socket<32> targ_socket;

  Target* target;
  SC_CTOR(Parent_of_target) : targ_socket("targ_socket") {
    target = new Target("target");

    // here MUST use  tlm target socket.bind(simple target socket)
    // if use   simple target socket.bind (tlm target socket)  may lead to simulation error
    //        Error: (E120) sc_export instance has no interface: xxxxxxx
    // target->targ_socket(targ_socket);  //error use    
    targ_socket.bind( target->targ_socket ); // Bind parent target socket to target socket
  }
};

//main
int sc_main(int argc, char ** argv)
{
  Parent_of_initiator *init;
  Parent_of_target *targ;
  
  init = new Parent_of_initiator("init");
  targ = new Parent_of_target("targ");
  init->init_socket.bind(targ->targ_socket); // Bind initiator socket to target socket at top level
  std::cout<<"test pass"<<std::endl;
  return 0;
}