simple_target_socket.h

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  with this work for additional information regarding copyright ownership.
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  (the "License"); you may not use this file except in compliance with the
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#ifndef __SYSTEMC_EXT_TLM_UTILS_SIMPLE_TARGET_SOCKET_H__
#define __SYSTEMC_EXT_TLM_UTILS_SIMPLE_TARGET_SOCKET_H__

#include "../core/sc_event.hh"
#include "../core/sc_module.hh"
#include "../core/sc_port.hh"
#include "../core/sc_spawn.hh"
#include "../tlm_core/2/generic_payload/gp.hh"
#include "../tlm_core/2/interfaces/fw_bw_ifs.hh"
#include "../tlm_core/2/sockets/initiator_socket.hh"
#include "../tlm_core/2/sockets/target_socket.hh"
#include "../utils/sc_report_handler.hh"
#include "convenience_socket_bases.h"
#include "peq_with_get.h"

namespace tlm_utils
{

template <typename MODULE, unsigned int BUSWIDTH, typename TYPES,
          sc_core::sc_port_policy POL=sc_core::SC_ONE_OR_MORE_BOUND>
class simple_target_socket_b :
    public tlm::tlm_target_socket<BUSWIDTH, TYPES, 1, POL>,
    protected simple_socket_base
{
    friend class fw_process;
    friend class bw_process;
  public:
    typedef typename TYPES::tlm_payload_type transaction_type;
    typedef typename TYPES::tlm_phase_type phase_type;
    typedef tlm::tlm_sync_enum sync_enum_type;
    typedef tlm::tlm_fw_transport_if<TYPES> fw_interface_type;
    typedef tlm::tlm_bw_transport_if<TYPES> bw_interface_type;
    typedef tlm::tlm_target_socket<BUSWIDTH, TYPES, 1, POL>  base_type;

  public:
    static const char *
    default_name()
    {
        return sc_core::sc_gen_unique_name("simple_target_socket");
    }

    explicit simple_target_socket_b(const char *n=default_name()) :
        base_type(n), m_fw_process(this), m_bw_process(this)
    {
        bind(m_fw_process);
    }

    using base_type::bind;

    // bw transport must come through us.
    tlm::tlm_bw_transport_if<TYPES> *operator -> () { return &m_bw_process; }

    // REGISTER_XXX
    void
    register_nb_transport_fw(MODULE *mod,
            sync_enum_type (MODULE::*cb)(
                transaction_type &, phase_type &, sc_core::sc_time &))
    {
        elaboration_check("register_nb_transport_fw");
        m_fw_process.set_nb_transport_ptr(mod, cb);
    }

    void
    register_b_transport(MODULE *mod,
            void (MODULE::*cb)(transaction_type &, sc_core::sc_time &))
    {
        elaboration_check("register_b_transport");
        m_fw_process.set_b_transport_ptr(mod, cb);
    }

    void
    register_transport_dbg(MODULE *mod,
            unsigned int (MODULE::*cb)(transaction_type &))
    {
        elaboration_check("register_transport_dbg");
        m_fw_process.set_transport_dbg_ptr(mod, cb);
    }

    void
    register_get_direct_mem_ptr(MODULE *mod,
            bool (MODULE::*cb)(transaction_type &, tlm::tlm_dmi &))
    {
        elaboration_check("register_get_direct_mem_ptr");
        m_fw_process.set_get_direct_mem_ptr(mod, cb);
    }

  protected:
    void
    start_of_simulation()
    {
        base_type::start_of_simulation();
        m_fw_process.start_of_simulation();
    }

  private:
    // Make call on bw path.
    sync_enum_type
    bw_nb_transport(transaction_type &trans, phase_type &phase,
                    sc_core::sc_time &t)
    {
        return base_type::operator -> ()->nb_transport_bw(trans, phase, t);
    }

    void
    bw_invalidate_direct_mem_ptr(sc_dt::uint64 s, sc_dt::uint64 e)
    {
        base_type::operator -> ()->invalidate_direct_mem_ptr(s, e);
    }

    // Helper class to handle bw path calls Needed to detect transaction end
    // when called from b_transport.
    class bw_process : public tlm::tlm_bw_transport_if<TYPES>
    {
      public:
        bw_process(simple_target_socket_b *p_own) : m_owner(p_own) {}

        sync_enum_type
        nb_transport_bw(transaction_type &trans, phase_type &phase,
                        sc_core::sc_time &t)
        {
            typename std::map<transaction_type *,
                              sc_core::sc_event *>::iterator it =
                                  m_owner->m_pending_trans.find(&trans);

            if (it == m_owner->m_pending_trans.end()) {
                // Not a blocking call, forward.
                return m_owner->bw_nb_transport(trans, phase, t);

            }

            if (phase == tlm::END_REQ) {
                m_owner->m_end_request.notify(sc_core::SC_ZERO_TIME);
                return tlm::TLM_ACCEPTED;
            }
            if (phase == tlm::BEGIN_RESP) {
                if (m_owner->m_current_transaction == &trans) {
                    m_owner->m_end_request.notify(sc_core::SC_ZERO_TIME);
                }
                it->second->notify(t);
                m_owner->m_pending_trans.erase(it);
                return tlm::TLM_COMPLETED;
            }
            m_owner->display_error("invalid phase received");
            return tlm::TLM_COMPLETED;
        }

        void
        invalidate_direct_mem_ptr(sc_dt::uint64 s, sc_dt::uint64 e)
        {
            return m_owner->bw_invalidate_direct_mem_ptr(s, e);
        }

      private:
        simple_target_socket_b *m_owner;
    };

    class fw_process : public tlm::tlm_fw_transport_if<TYPES>,
                      public tlm::tlm_mm_interface
    {
      public:
        typedef sync_enum_type (MODULE::*NBTransportPtr)(
                transaction_type &, phase_type &, sc_core::sc_time &);
        typedef void (MODULE::*BTransportPtr)(
                transaction_type &, sc_core::sc_time &);
        typedef unsigned int (MODULE::*TransportDbgPtr)(transaction_type &);
        typedef bool (MODULE::*GetDirectMemPtr)(
                transaction_type &, tlm::tlm_dmi &);

        fw_process(simple_target_socket_b *p_own) :
            m_owner(p_own), m_mod(0), m_nb_transport_ptr(0),
            m_b_transport_ptr(0), m_transport_dbg_ptr(0),
            m_get_direct_mem_ptr(0),
            m_peq(sc_core::sc_gen_unique_name("m_peq")),
            m_response_in_progress(false)
        {}

        void
        start_of_simulation()
        {
            // Only spawn b2nb_thread, if needed.
            if (!m_b_transport_ptr && m_nb_transport_ptr) {
                sc_core::sc_spawn_options opts;
                opts.set_sensitivity(&m_peq.get_event());
                opts.dont_initialize();
                sc_core::sc_spawn(sc_bind(&fw_process::b2nb_thread, this),
                        sc_core::sc_gen_unique_name("b2nb_thread"), &opts);
            }
        }

        void
        set_nb_transport_ptr(MODULE *mod, NBTransportPtr p)
        {
            if (m_nb_transport_ptr) {
                m_owner->display_warning(
                        "non-blocking callback already registered");
                return;
            }
            sc_assert(!m_mod || m_mod == mod);
            m_mod = mod;
            m_nb_transport_ptr = p;
        }

        void
        set_b_transport_ptr(MODULE *mod, BTransportPtr p)
        {
            if (m_b_transport_ptr) {
                m_owner->display_warning(
                        "blocking callback already registered");
                return;
            }
            sc_assert(!m_mod || m_mod == mod);
            m_mod = mod;
            m_b_transport_ptr = p;
        }

        void
        set_transport_dbg_ptr(MODULE *mod, TransportDbgPtr p)
        {
            if (m_transport_dbg_ptr) {
                m_owner->display_warning("debug callback already registered");
                return;
            }
            sc_assert(!m_mod || m_mod == mod);
            m_mod = mod;
            m_transport_dbg_ptr = p;
        }

        void
        set_get_direct_mem_ptr(MODULE *mod, GetDirectMemPtr p)
        {
            if (m_get_direct_mem_ptr) {
                m_owner->display_warning(
                        "get DMI pointer callback already registered");
                return;
            }
            sc_assert(!m_mod || m_mod == mod);
            m_mod = mod;
            m_get_direct_mem_ptr = p;
        }

        // Interface implementation.
        sync_enum_type
        nb_transport_fw(transaction_type &trans, phase_type &phase,
                        sc_core::sc_time & t)
        {
            if (m_nb_transport_ptr) {
                // Forward call.
                sc_assert(m_mod);
                return (m_mod->*m_nb_transport_ptr)(trans, phase, t);
            }

            // nb->b conversion
            if (m_b_transport_ptr) {
                if (phase == tlm::BEGIN_REQ) {
                    // Prepare thread to do blocking call.
                    process_handle_class *ph =
                        m_process_handle.get_handle(&trans);

                    if (!ph) { // Create new dynamic process.
                        ph = new process_handle_class(&trans);
                        m_process_handle.put_handle(ph);

                        sc_core::sc_spawn_options opts;
                        opts.dont_initialize();
                        opts.set_sensitivity(&ph->m_e);

                        sc_core::sc_spawn(
                                sc_bind(&fw_process::nb2b_thread, this, ph),
                                sc_core::sc_gen_unique_name("nb2b_thread"),
                                &opts);
                    }

                    ph->m_e.notify(t);
                    return tlm::TLM_ACCEPTED;
                }
                if (phase == tlm::END_RESP) {
                    m_response_in_progress = false;
                    m_end_response.notify(t);
                    return tlm::TLM_COMPLETED;
                }
                m_owner->display_error("invalid phase received");
                return tlm::TLM_COMPLETED;
            }
             m_owner->display_error(
                     "no non-blocking transport callback registered");
            return tlm::TLM_COMPLETED;
        }

        void
        b_transport(transaction_type &trans, sc_core::sc_time &t)
        {
            if (m_b_transport_ptr) {
                // Forward call.
                sc_assert(m_mod);
                (m_mod->*m_b_transport_ptr)(trans, t);
                return;
            }

            // b->nb conversion
            if (m_nb_transport_ptr) {
                m_peq.notify(trans, t);
                t = sc_core::SC_ZERO_TIME;

                mm_end_event_ext mm_ext;
                const bool mm_added = !trans.has_mm();

                if (mm_added) {
                    trans.set_mm(this);
                    trans.set_auto_extension(&mm_ext);
                    trans.acquire();
                }

                // Wait until transaction is finished.
                sc_core::sc_event end_event;
                m_owner->m_pending_trans[&trans] = &end_event;
                sc_core::wait(end_event);

                if (mm_added) {
                    // Release will not delete the transaction, it will
                    // notify mm_ext.done.
                    trans.release();
                    if (trans.get_ref_count()) {
                        sc_core::wait(mm_ext.done);
                    }
                    trans.set_mm(0);
                }
                return;
            }

            // Should not be reached.
            m_owner->display_error(
                    "no blocking transport callback registered");
        }

        unsigned int
        transport_dbg(transaction_type &trans)
        {
            if (m_transport_dbg_ptr) {
                // Forward call.
                sc_assert(m_mod);
                return (m_mod->*m_transport_dbg_ptr)(trans);
            }
            // No debug support.
            return 0;
        }

        bool
        get_direct_mem_ptr(transaction_type &trans, tlm::tlm_dmi &dmi_data)
        {
            if (m_get_direct_mem_ptr) {
                // Forward call.
                sc_assert(m_mod);
                return (m_mod->*m_get_direct_mem_ptr)(trans, dmi_data);
            }
            // No DMI support.
            dmi_data.allow_read_write();
            dmi_data.set_start_address(0x0);
            dmi_data.set_end_address((sc_dt::uint64)-1);
            return false;
        }

      private:

        // Dynamic process handler for nb2b conversion.

        class process_handle_class
        {
          public:
            explicit process_handle_class(transaction_type *trans) :
                m_trans(trans), m_suspend(false)
            {}

            transaction_type *m_trans;
            sc_core::sc_event m_e;
            bool m_suspend;
        };

        class process_handle_list
        {
          public:
            process_handle_list() {}

            ~process_handle_list()
            {
                for (typename std::vector<
                        process_handle_class *>::iterator it = v.begin(),
                        end = v.end(); it != end; ++it) {
                    delete *it;
                }
            }

            process_handle_class *
            get_handle(transaction_type *trans)
            {
                typename std::vector<process_handle_class *>::iterator it;

                for (it = v.begin(); it != v.end(); it++) {
                    if ((*it)->m_suspend) {
                        // Found suspended dynamic process, re-use it.
                        (*it)->m_trans = trans; // Replace to new one.
                        (*it)->m_suspend = false;
                        return *it;
                    }
                }
                return NULL; // No suspended process.
            }

            void
            put_handle(process_handle_class *ph)
            {
                v.push_back(ph);
            }

          private:
            std::vector<process_handle_class*> v;
        };

        process_handle_list m_process_handle;

        void
        nb2b_thread(process_handle_class *h)
        {
            while (1) {
                transaction_type *trans = h->m_trans;
                sc_core::sc_time t = sc_core::SC_ZERO_TIME;

                // Forward call.
                sc_assert(m_mod);
                (m_mod->*m_b_transport_ptr)(*trans, t);

                sc_core::wait(t);

                // Return path.
                while (m_response_in_progress) {
                    sc_core::wait(m_end_response);
                }
                t = sc_core::SC_ZERO_TIME;
                phase_type phase = tlm::BEGIN_RESP;
                sync_enum_type sync =
                    m_owner->bw_nb_transport(*trans, phase, t);
                if (!(sync == tlm::TLM_COMPLETED ||
                            (sync == tlm::TLM_UPDATED &&
                             phase == tlm::END_RESP))) {
                    m_response_in_progress = true;
                }

                // Suspend until next transaction.
                h->m_suspend = true;
                sc_core::wait();
            }
        }

        void
        b2nb_thread()
        {
            while (true) {
                transaction_type *trans;
                while ((trans = m_peq.get_next_transaction()) != 0) {
                    sc_assert(m_mod);
                    sc_assert(m_nb_transport_ptr);
                    phase_type phase = tlm::BEGIN_REQ;
                    sc_core::sc_time t = sc_core::SC_ZERO_TIME;

                    switch ((m_mod->*m_nb_transport_ptr)(*trans, phase, t)) {
                      case tlm::TLM_COMPLETED:
                        {
                            // Notify transaction is finished.
                            typename std::map<transaction_type *,
                                     sc_core::sc_event *>::iterator it =
                                         m_owner->m_pending_trans.find(trans);
                            sc_assert(it != m_owner->m_pending_trans.end());
                            it->second->notify(t);
                            m_owner->m_pending_trans.erase(it);
                            break;
                        }

                      case tlm::TLM_ACCEPTED:
                      case tlm::TLM_UPDATED:
                        switch (phase) {
                          case tlm::BEGIN_REQ:
                            m_owner->m_current_transaction = trans;
                            sc_core::wait(m_owner->m_end_request);
                            m_owner->m_current_transaction = 0;
                            break;

                          case tlm::END_REQ:
                            sc_core::wait(t);
                            break;

                          case tlm::BEGIN_RESP:
                            {
                                phase = tlm::END_RESP;
                                // This line is a bug fix added in TLM-2.0.2
                                sc_core::wait(t);
                                t = sc_core::SC_ZERO_TIME;
                                (m_mod->*m_nb_transport_ptr)(
                                        *trans, phase, t);

                                // Notify transaction is finished.
                                typename std::map<transaction_type *,
                                         sc_core::sc_event *>::iterator it =
                                             m_owner->m_pending_trans.find(
                                                     trans);
                                sc_assert(it !=
                                        m_owner->m_pending_trans.end());
                                it->second->notify(t);
                                m_owner->m_pending_trans.erase(it);
                                break;
                            }

                          default:
                            m_owner->display_error("invalid phase received");
                        }
                        break;

                      default:
                        m_owner->display_error("invalid sync value received");
                    }
                }
                sc_core::wait();
            }
        }

        void
        free(tlm::tlm_generic_payload *trans)
        {
            mm_end_event_ext *ext =
                trans->template get_extension<mm_end_event_ext>();
            sc_assert(ext);
            // Notify event first before freeing extensions (reset).
            ext->done.notify();
            trans->reset();
        }

      private:
        struct mm_end_event_ext : public tlm::tlm_extension<mm_end_event_ext>
        {
            tlm::tlm_extension_base *clone() const { return NULL; }
            void free() {}
            void copy_from(tlm::tlm_extension_base const &) {}
            sc_core::sc_event done;
        };

      private:
        simple_target_socket_b *m_owner;
        MODULE *m_mod;
        NBTransportPtr m_nb_transport_ptr;
        BTransportPtr m_b_transport_ptr;
        TransportDbgPtr m_transport_dbg_ptr;
        GetDirectMemPtr m_get_direct_mem_ptr;
        peq_with_get<transaction_type> m_peq;
        bool m_response_in_progress;
        sc_core::sc_event m_end_response;
    };

  private:
    const sc_core::sc_object *get_socket() const { return this; }

  private:
    fw_process m_fw_process;
    bw_process m_bw_process;
    std::map<transaction_type *, sc_core::sc_event *> m_pending_trans;
    sc_core::sc_event m_end_request;
    transaction_type* m_current_transaction;
};

template <typename MODULE, unsigned int BUSWIDTH=32,
          typename TYPES=tlm::tlm_base_protocol_types>
class simple_target_socket :
    public simple_target_socket_b<MODULE, BUSWIDTH, TYPES>
{
    typedef simple_target_socket_b<MODULE, BUSWIDTH, TYPES> socket_b;
  public:
    simple_target_socket() : socket_b() {}
    explicit simple_target_socket(const char *name) : socket_b(name) {}
};

template <typename MODULE, unsigned int BUSWIDTH=32,
          typename TYPES=tlm::tlm_base_protocol_types>
class simple_target_socket_optional :
    public simple_target_socket_b<MODULE, BUSWIDTH, TYPES,
                                  sc_core::SC_ZERO_OR_MORE_BOUND>
{
    typedef simple_target_socket_b<MODULE, BUSWIDTH, TYPES,
                                   sc_core::SC_ZERO_OR_MORE_BOUND> socket_b;
  public:
    simple_target_socket_optional() : socket_b() {}
    explicit simple_target_socket_optional(const char *name) :
        socket_b(name)
    {}
};

// ID Tagged version.
template <typename MODULE, unsigned int BUSWIDTH, typename TYPES,
          sc_core::sc_port_policy POL=sc_core::SC_ONE_OR_MORE_BOUND>
class simple_target_socket_tagged_b :
    public tlm::tlm_target_socket<BUSWIDTH, TYPES, 1, POL>,
    protected simple_socket_base
{
    friend class fw_process;
    friend class bw_process;
  public:
    typedef typename TYPES::tlm_payload_type transaction_type;
    typedef typename TYPES::tlm_phase_type phase_type;
    typedef tlm::tlm_sync_enum sync_enum_type;
    typedef tlm::tlm_fw_transport_if<TYPES> fw_interface_type;
    typedef tlm::tlm_bw_transport_if<TYPES> bw_interface_type;
    typedef tlm::tlm_target_socket<BUSWIDTH, TYPES, 1, POL> base_type;

  public:
    static const char *
    default_name()
    {
        return sc_core::sc_gen_unique_name("simple_target_socket_tagged");
    }

    explicit simple_target_socket_tagged_b(const char *n=default_name()) :
        base_type(n), m_fw_process(this), m_bw_process(this)
    {
        bind(m_fw_process);
    }

    using base_type::bind;

    // bw transport must come through us.
    tlm::tlm_bw_transport_if<TYPES> *operator -> () { return &m_bw_process; }

    // REGISTER_XXX
    void
    register_nb_transport_fw(MODULE *mod,
            sync_enum_type (MODULE::*cb)(int id, transaction_type &,
                                         phase_type &, sc_core::sc_time &),
            int id)
    {
        elaboration_check("register_nb_transport_fw");
        m_fw_process.set_nb_transport_ptr(mod, cb);
        m_fw_process.set_nb_transport_user_id(id);
    }

    void
    register_b_transport(MODULE *mod,
            void (MODULE::*cb)(int id, transaction_type &,
                               sc_core::sc_time &),
            int id)
    {
        elaboration_check("register_b_transport");
        m_fw_process.set_b_transport_ptr(mod, cb);
        m_fw_process.set_b_transport_user_id(id);
    }

    void
    register_transport_dbg(MODULE *mod,
            unsigned int (MODULE::*cb)(int id, transaction_type &), int id)
    {
        elaboration_check("register_transport_dbg");
        m_fw_process.set_transport_dbg_ptr(mod, cb);
        m_fw_process.set_transport_dbg_user_id(id);
    }

    void
    register_get_direct_mem_ptr(MODULE *mod,
            bool (MODULE::*cb)(int id, transaction_type &, tlm::tlm_dmi &),
            int id)
    {
        elaboration_check("register_get_direct_mem_ptr");
        m_fw_process.set_get_direct_mem_ptr(mod, cb);
        m_fw_process.set_get_dmi_user_id(id);
    }

  protected:
    void
    start_of_simulation()
    {
        base_type::start_of_simulation();
        m_fw_process.start_of_simulation();
    }

  private:
    // Make call on bw path.
    sync_enum_type
    bw_nb_transport(transaction_type &trans, phase_type &phase,
                    sc_core::sc_time &t)
    {
        return base_type::operator -> ()->nb_transport_bw(trans, phase, t);
    }

    void
    bw_invalidate_direct_mem_ptr(sc_dt::uint64 s, sc_dt::uint64 e)
    {
        base_type::operator -> ()->invalidate_direct_mem_ptr(s, e);
    }

    // Helper class to handle bw path calls Needed to detect transaction
    // end when called from b_transport.
    class bw_process : public tlm::tlm_bw_transport_if<TYPES>
    {
      public:
        bw_process(simple_target_socket_tagged_b *p_own) : m_owner(p_own) {}

        sync_enum_type
        nb_transport_bw(transaction_type &trans, phase_type &phase,
                        sc_core::sc_time &t)
        {
            typename std::map<transaction_type *,
                              sc_core::sc_event *>::iterator it =
                                  m_owner->m_pending_trans.find(&trans);

            if (it == m_owner->m_pending_trans.end()) {
                // Not a blocking call, forward.
                return m_owner->bw_nb_transport(trans, phase, t);
            }
            if (phase == tlm::END_REQ) {
                m_owner->m_end_request.notify(sc_core::SC_ZERO_TIME);
                return tlm::TLM_ACCEPTED;
            }
            if (phase == tlm::BEGIN_RESP) {
                if (m_owner->m_current_transaction == &trans) {
                    m_owner->m_end_request.notify(sc_core::SC_ZERO_TIME);
                }
                it->second->notify(t);
                m_owner->m_pending_trans.erase(it);
                return tlm::TLM_COMPLETED;
            }
            m_owner->display_error("invalid phase received");
            return tlm::TLM_COMPLETED;
        }

        void
        invalidate_direct_mem_ptr(sc_dt::uint64 s, sc_dt::uint64 e)
        {
            return m_owner->bw_invalidate_direct_mem_ptr(s, e);
        }

      private:
        simple_target_socket_tagged_b *m_owner;
    };

    class fw_process : public tlm::tlm_fw_transport_if<TYPES>,
                       public tlm::tlm_mm_interface
    {
      public:
        typedef sync_enum_type (MODULE::*NBTransportPtr)(
                int id, transaction_type &, phase_type &,
                sc_core::sc_time &);
        typedef void (MODULE::*BTransportPtr)(
                int id, transaction_type &, sc_core::sc_time &);
        typedef unsigned int (MODULE::*TransportDbgPtr)(
                int id, transaction_type &);
        typedef bool (MODULE::*GetDirectMemPtr)(
                int id, transaction_type &, tlm::tlm_dmi &);

        fw_process(simple_target_socket_tagged_b *p_own) :
            m_owner(p_own), m_mod(0), m_nb_transport_ptr(0),
            m_b_transport_ptr(0), m_transport_dbg_ptr(0),
            m_get_direct_mem_ptr(0), m_nb_transport_user_id(0),
            m_b_transport_user_id(0), m_transport_dbg_user_id(0),
            m_get_dmi_user_id(0),
            m_peq(sc_core::sc_gen_unique_name("m_peq")),
            m_response_in_progress(false)
        {}

        void
        start_of_simulation()
        {
            if (!m_b_transport_ptr && m_nb_transport_ptr) {
                // Only spawn b2nb_thread if needed.
                sc_core::sc_spawn_options opts;
                opts.set_sensitivity(&m_peq.get_event());
                opts.dont_initialize();
                sc_core::sc_spawn(sc_bind(&fw_process::b2nb_thread, this),
                        sc_core::sc_gen_unique_name("b2nb_thread"), &opts);
            }
        }

        void set_nb_transport_user_id(int id) { m_nb_transport_user_id = id; }
        void set_b_transport_user_id(int id) { m_b_transport_user_id = id; }
        void
        set_transport_dbg_user_id(int id)
        {
            m_transport_dbg_user_id = id;
        }
        void set_get_dmi_user_id(int id) { m_get_dmi_user_id = id; }

        void
        set_nb_transport_ptr(MODULE *mod, NBTransportPtr p)
        {
            if (m_nb_transport_ptr) {
                m_owner->display_warning(
                        "non-blocking callback already registered");
                return;
            }
            sc_assert(!m_mod || m_mod == mod);
            m_mod = mod;
            m_nb_transport_ptr = p;
        }

        void
        set_b_transport_ptr(MODULE* mod, BTransportPtr p)
        {
            if (m_b_transport_ptr) {
                m_owner->display_warning(
                        "blocking callback already registered");
                return;
            }
            sc_assert(!m_mod || m_mod == mod);
            m_mod = mod;
            m_b_transport_ptr = p;
        }

        void
        set_transport_dbg_ptr(MODULE *mod, TransportDbgPtr p)
        {
            if (m_transport_dbg_ptr) {
                m_owner->display_warning(
                        "debug callback already registered");
                return;
            }
            sc_assert(!m_mod || m_mod == mod);
            m_mod = mod;
            m_transport_dbg_ptr = p;
        }

        void
        set_get_direct_mem_ptr(MODULE *mod, GetDirectMemPtr p)
        {
            if (m_get_direct_mem_ptr) {
                m_owner->display_warning(
                        "get DMI pointer callback already registered");
            }
            sc_assert(!m_mod || m_mod == mod);
            m_mod = mod;
            m_get_direct_mem_ptr = p;
        }

        // Interface implementation.
        sync_enum_type
        nb_transport_fw(transaction_type &trans, phase_type &phase,
                        sc_core::sc_time &t)
        {
            if (m_nb_transport_ptr) {
                // Forward call.
                sc_assert(m_mod);
                return (m_mod->*m_nb_transport_ptr)(
                        m_nb_transport_user_id, trans, phase, t);
            }

            // nb->b conversion
            if (m_b_transport_ptr) {
                if (phase == tlm::BEGIN_REQ) {

                    // Prepare thread to do blocking call.
                    process_handle_class *ph =
                        m_process_handle.get_handle(&trans);

                    if (!ph) { // Create new dynamic process.
                        ph = new process_handle_class(&trans);
                        m_process_handle.put_handle(ph);

                        sc_core::sc_spawn_options opts;
                        opts.dont_initialize();
                        opts.set_sensitivity(&ph->m_e);

                        sc_core::sc_spawn(
                                sc_bind(&fw_process::nb2b_thread, this, ph),
                                sc_core::sc_gen_unique_name("nb2b_thread"),
                                &opts);
                    }

                    ph->m_e.notify(t);
                    return tlm::TLM_ACCEPTED;
                }
                if (phase == tlm::END_RESP) {
                    m_response_in_progress = false;
                    m_end_response.notify(t);
                    return tlm::TLM_COMPLETED;
                }
                m_owner->display_error("invalid phase");
                return tlm::TLM_COMPLETED;
            }

            m_owner->display_error(
                    "no non-blocking transport callback registered");
            return tlm::TLM_COMPLETED;
        }

        void
        b_transport(transaction_type &trans, sc_core::sc_time &t)
        {
            if (m_b_transport_ptr) {
                // Forward call.
                sc_assert(m_mod);
                (m_mod->*m_b_transport_ptr)(m_b_transport_user_id, trans, t);
                return;
            }

            // b->nb conversion
            if (m_nb_transport_ptr) {
                m_peq.notify(trans, t);
                t = sc_core::SC_ZERO_TIME;

                mm_end_event_ext mm_ext;
                const bool mm_added = !trans.has_mm();

                if (mm_added) {
                    trans.set_mm(this);
                    trans.set_auto_extension(&mm_ext);
                    trans.acquire();
                }

                // Wait until transaction is finished.
                sc_core::sc_event end_event;
                m_owner->m_pending_trans[&trans] = &end_event;
                sc_core::wait(end_event);

                if (mm_added) {
                    // Release will not delete the transaction, it will
                    // notify mm_ext.done.
                    trans.release();
                    if (trans.get_ref_count()) {
                        sc_core::wait(mm_ext.done);
                    }
                    trans.set_mm(0);
                }
                return;
            }

            m_owner->display_error("no transport callback registered");
        }

        unsigned int
        transport_dbg(transaction_type &trans)
        {
            if (m_transport_dbg_ptr) {
                // Forward call.
                sc_assert(m_mod);
                return (m_mod->*m_transport_dbg_ptr)(
                        m_transport_dbg_user_id, trans);
            }
            // No debug support.
            return 0;
        }

        bool
        get_direct_mem_ptr(transaction_type &trans, tlm::tlm_dmi &dmi_data)
        {
            if (m_get_direct_mem_ptr) {
                // Forward call.
                sc_assert(m_mod);
                return (m_mod->*m_get_direct_mem_ptr)(
                        m_get_dmi_user_id, trans, dmi_data);
            }
            // No DMI support.
            dmi_data.allow_read_write();
            dmi_data.set_start_address(0x0);
            dmi_data.set_end_address((sc_dt::uint64)-1);
            return false;
        }

      private:

        // Dynamic process handler for nb2b conversion.
        class process_handle_class
        {
          public:
            explicit process_handle_class(transaction_type *trans) :
                m_trans(trans), m_suspend(false)
            {}

            transaction_type *m_trans;
            sc_core::sc_event  m_e;
            bool m_suspend;
        };

        class process_handle_list
        {
          public:
            process_handle_list() {}

            ~process_handle_list()
            {
                for (typename std::vector<
                        process_handle_class *>::iterator it = v.begin(),
                        end = v.end(); it != end; ++it) {
                    delete *it;
                }
            }

            process_handle_class *
            get_handle(transaction_type *trans)
            {
                typename std::vector<process_handle_class *>::iterator it;

                for (it = v.begin(); it != v.end(); it++) {
                    if ((*it)->m_suspend) {
                        // Found suspended dynamic process, re-use it.
                        (*it)->m_trans = trans; // Replace to new one.
                        (*it)->m_suspend = false;
                        return *it;
                    }
                }
                return NULL; // No suspended process.
            }

            void put_handle(process_handle_class *ph) { v.push_back(ph); }

          private:
            std::vector<process_handle_class *> v;
        };

        process_handle_list m_process_handle;

        void
        nb2b_thread(process_handle_class *h)
        {

            while (1) {
                transaction_type *trans = h->m_trans;
                sc_core::sc_time t = sc_core::SC_ZERO_TIME;

                // Forward call.
                sc_assert(m_mod);
                (m_mod->*m_b_transport_ptr)(
                        m_b_transport_user_id, *trans, t);

                sc_core::wait(t);

                // Return path.
                while (m_response_in_progress) {
                    sc_core::wait(m_end_response);
                }
                t = sc_core::SC_ZERO_TIME;
                phase_type phase = tlm::BEGIN_RESP;
                sync_enum_type sync =
                    m_owner->bw_nb_transport(*trans, phase, t);
                if (!(sync == tlm::TLM_COMPLETED ||
                            (sync == tlm::TLM_UPDATED &&
                             phase == tlm::END_RESP))) {
                    m_response_in_progress = true;
                }

                // Suspend until next transaction.
                h->m_suspend = true;
                sc_core::wait();
            }
        }

        void
        b2nb_thread()
        {
            while (true) {
                transaction_type *trans;
                while ((trans = m_peq.get_next_transaction()) != 0) {
                    sc_assert(m_mod);
                    sc_assert(m_nb_transport_ptr);
                    phase_type phase = tlm::BEGIN_REQ;
                    sc_core::sc_time t = sc_core::SC_ZERO_TIME;

                    switch ((m_mod->*m_nb_transport_ptr)(
                                m_nb_transport_user_id, *trans, phase, t)) {
                      case tlm::TLM_COMPLETED:
                        {
                            // Notify transaction is finished.
                            typename std::map<transaction_type *,
                                     sc_core::sc_event *>::iterator it =
                                         m_owner->m_pending_trans.find(trans);
                            sc_assert(it != m_owner->m_pending_trans.end());
                            it->second->notify(t);
                            m_owner->m_pending_trans.erase(it);
                            break;
                        }

                      case tlm::TLM_ACCEPTED:
                      case tlm::TLM_UPDATED:
                        switch (phase) {
                          case tlm::BEGIN_REQ:
                            m_owner->m_current_transaction = trans;
                            sc_core::wait(m_owner->m_end_request);
                            m_owner->m_current_transaction = 0;
                            break;

                          case tlm::END_REQ:
                            sc_core::wait(t);
                            break;

                          case tlm::BEGIN_RESP:
                            {
                                phase = tlm::END_RESP;
                                // This line is a bug fix added in TLM-2.0.2.
                                sc_core::wait(t);
                                t = sc_core::SC_ZERO_TIME;
                                (m_mod->*m_nb_transport_ptr)(
                                        m_nb_transport_user_id,
                                        *trans, phase, t);

                                // Notify transaction is finished.
                                typename std::map<transaction_type *,
                                         sc_core::sc_event *>::iterator it =
                                             m_owner->m_pending_trans.find(
                                                     trans);
                                sc_assert(it !=
                                        m_owner->m_pending_trans.end());
                                it->second->notify(t);
                                m_owner->m_pending_trans.erase(it);
                                break;
                            }

                          default:
                            m_owner->display_error("invalid phase received");
                        };
                        break;

                      default:
                        m_owner->display_error("invalid sync value received");
                    }
                }
                sc_core::wait();
            }
        }

        void
        free(tlm::tlm_generic_payload *trans)
        {
            mm_end_event_ext *ext =
                trans->template get_extension<mm_end_event_ext>();
            sc_assert(ext);
            // Notify event first before freeing extensions (reset).
            ext->done.notify();
            trans->reset();
        }

      private:
        struct mm_end_event_ext : public tlm::tlm_extension<mm_end_event_ext>
        {
            tlm::tlm_extension_base *clone() const { return NULL; }
            void free() {}
            void copy_from(tlm::tlm_extension_base const &) {}
            sc_core::sc_event done;
        };

      private:
        simple_target_socket_tagged_b *m_owner;
        MODULE *m_mod;
        NBTransportPtr m_nb_transport_ptr;
        BTransportPtr m_b_transport_ptr;
        TransportDbgPtr m_transport_dbg_ptr;
        GetDirectMemPtr m_get_direct_mem_ptr;
        int m_nb_transport_user_id;
        int m_b_transport_user_id;
        int m_transport_dbg_user_id;
        int m_get_dmi_user_id;
        peq_with_get<transaction_type> m_peq;
        bool m_response_in_progress;
        sc_core::sc_event m_end_response;
    };

  private:
    const sc_core::sc_object *get_socket() const { return this; }

  private:
    fw_process m_fw_process;
    bw_process m_bw_process;
    std::map<transaction_type *, sc_core::sc_event *> m_pending_trans;
    sc_core::sc_event m_end_request;
    transaction_type* m_current_transaction;
};

template <typename MODULE, unsigned int BUSWIDTH=32,
          typename TYPES=tlm::tlm_base_protocol_types>
class simple_target_socket_tagged :
    public simple_target_socket_tagged_b<MODULE, BUSWIDTH, TYPES>
{
    typedef simple_target_socket_tagged_b<MODULE, BUSWIDTH, TYPES> socket_b;
  public:
    simple_target_socket_tagged() : socket_b() {}
    explicit simple_target_socket_tagged(const char *name) : socket_b(name) {}
};

template <typename MODULE, unsigned int BUSWIDTH=32,
          typename TYPES=tlm::tlm_base_protocol_types>
class simple_target_socket_tagged_optional :
    public simple_target_socket_tagged_b<MODULE, BUSWIDTH, TYPES,
                                         sc_core::SC_ZERO_OR_MORE_BOUND>
{
    typedef simple_target_socket_tagged_b<
        MODULE, BUSWIDTH, TYPES, sc_core::SC_ZERO_OR_MORE_BOUND> socket_b;
  public:
    simple_target_socket_tagged_optional() : socket_b() {}
    explicit simple_target_socket_tagged_optional(const char *name) :
        socket_b(name)
    {}
};

} // namespace tlm_utils

#endif /* __SYSTEMC_EXT_TLM_UTILS_SIMPLE_TARGET_SOCKET_H__ */