util/tlm/src/sc_master_port.cc - arm/gem5 - Git at Google

 /*
  * Copyright (c) 2016, Dresden University of Technology (TU Dresden)
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  * 1. Redistributions of source code must retain the above copyright notice,
  *    this list of conditions and the following disclaimer.
  *
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * 3. Neither the name of the copyright holder nor the names of its
  *    contributors may be used to endorse or promote products derived from
  *    this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER
  * 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; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 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.
  *
  * Authors: Christian Menard
  */

 #include <sstream>

 #include "master_transactor.hh"
 #include "params/ExternalMaster.hh"
 #include "sc_ext.hh"
 #include "sc_master_port.hh"
 #include "sim/system.hh"

 namespace Gem5SystemC
 {

 PacketPtr
 SCMasterPort::generatePacket(tlm::tlm_generic_payload& trans)
 {
     Request::Flags flags;
     auto req = new Request(trans.get_address(), trans.get_data_length(), flags,
                            owner.masterId);

     MemCmd cmd;

     switch (trans.get_command()) {
         case tlm::TLM_READ_COMMAND:
             cmd = MemCmd::ReadReq;
             break;
         case tlm::TLM_WRITE_COMMAND:
             cmd = MemCmd::WriteReq;
             break;
         default:
             SC_REPORT_FATAL("SCMasterPort",
                             "received transaction with unsupported command");
     }

     /*
      * Allocate a new Packet. The packet will be deleted when it returns from
      * the gem5 world as a response.
      */
     auto pkt = new Packet(req, cmd);
     pkt->dataStatic(trans.get_data_ptr());

     return pkt;
 }

 void
 SCMasterPort::destroyPacket(PacketPtr pkt)
 {
     delete pkt;
 }

 SCMasterPort::SCMasterPort(const std::string& name_,
                            const std::string& systemc_name,
                            ExternalMaster& owner_,
                            Gem5SimControl& simControl)
   : ExternalMaster::Port(name_, owner_),
     peq(this, &SCMasterPort::peq_cb),
     waitForRetry(false),
     pendingRequest(nullptr),
     pendingPacket(nullptr),
     needToSendRetry(false),
     responseInProgress(false),
     transactor(nullptr),
     simControl(simControl)
 {
     system =
         dynamic_cast<const ExternalMasterParams*>(owner_.params())->system;
 }

 void
 SCMasterPort::bindToTransactor(Gem5MasterTransactor* transactor)
 {
     sc_assert(this->transactor == nullptr);

     this->transactor = transactor;

     /*
      * Register the TLM non-blocking interface when using gem5 Timing mode and
      * the TLM blocking interface when using the gem5 Atomic mode.
      * Then the magic (TM) in simple_target_socket automatically transforms
      * non-blocking in blocking transactions and vice versa.
      *
      * NOTE: The mode may change during execution.
      */
     if (system->isTimingMode()) {
         SC_REPORT_INFO("SCMasterPort", "register non-blocking interface");
         transactor->socket.register_nb_transport_fw(this,
                                 &SCMasterPort::nb_transport_fw);
     } else if (system->isAtomicMode()) {
         SC_REPORT_INFO("SCMasterPort", "register blocking interface");
         transactor->socket.register_b_transport(this,
                                 &SCMasterPort::b_transport);
     } else {
         panic("gem5 operates neither in Timing nor in Atomic mode");
     }

     transactor->socket.register_transport_dbg(this,
                                               &SCMasterPort::transport_dbg);
 }

 void
 SCMasterPort::checkTransaction(tlm::tlm_generic_payload& trans)
 {
     if (trans.is_response_error()) {
         std::stringstream ss;
         ss << "Transaction returned with error, response status = "
            << trans.get_response_string();
         SC_REPORT_ERROR("TLM-2", ss.str().c_str());
     }
 }

 tlm::tlm_sync_enum
 SCMasterPort::nb_transport_fw(tlm::tlm_generic_payload& trans,
                               tlm::tlm_phase& phase, sc_core::sc_time& delay)
 {
     uint64_t adr = trans.get_address();
     unsigned len = trans.get_data_length();
     unsigned char* byteEnable = trans.get_byte_enable_ptr();
     unsigned width = trans.get_streaming_width();

     // check the transaction attributes for unsupported features ...
     if (byteEnable != 0) {
         trans.set_response_status(tlm::TLM_BYTE_ENABLE_ERROR_RESPONSE);
         return tlm::TLM_COMPLETED;
     }
     if (width < len) { // is this a burst request?
         trans.set_response_status(tlm::TLM_BURST_ERROR_RESPONSE);
         return tlm::TLM_COMPLETED;
     }

     // ... and queue the valid transaction
     trans.acquire();
     peq.notify(trans, phase, delay);
     return tlm::TLM_ACCEPTED;
 }

 void
 SCMasterPort::peq_cb(tlm::tlm_generic_payload& trans,
                        const tlm::tlm_phase& phase)
 {
     // catch up with SystemC time
     simControl.catchup();
     assert(curTick() == sc_core::sc_time_stamp().value());

     switch (phase) {
         case tlm::BEGIN_REQ:
             handleBeginReq(trans);
             break;
         case tlm::END_RESP:
             handleEndResp(trans);
             break;
         default:
             panic("unimplemented phase in callback");
     }

     // the functions called above may have scheduled gem5 events
     // -> notify the event loop handler
     simControl.notify();
 }

 void
 SCMasterPort::handleBeginReq(tlm::tlm_generic_payload& trans)
 {
     sc_assert(!waitForRetry);
     sc_assert(pendingRequest == nullptr);
     sc_assert(pendingPacket == nullptr);

     trans.acquire();

     PacketPtr pkt = nullptr;

     Gem5Extension* extension = nullptr;
     trans.get_extension(extension);

     // If there is an extension, this transaction was initiated by the gem5
     // world and we can pipe through the original packet. Otherwise, we
     // generate a new packet based on the transaction.
     if (extension != nullptr) {
         extension->setPipeThrough();
         pkt = extension->getPacket();
     } else {
         pkt = generatePacket(trans);
     }

     auto tlmSenderState = new TlmSenderState(trans);
     pkt->pushSenderState(tlmSenderState);

     if (sendTimingReq(pkt)) { // port is free -> send END_REQ immediately
         sendEndReq(trans);
         trans.release();
     } else { // port is blocked -> wait for retry before sending END_REQ
         waitForRetry = true;
         pendingRequest = &trans;
         pendingPacket = pkt;
     }
 }

 void
 SCMasterPort::handleEndResp(tlm::tlm_generic_payload& trans)
 {
     sc_assert(responseInProgress);

     responseInProgress = false;

     checkTransaction(trans);

     if (needToSendRetry) {
         sendRetryResp();
         needToSendRetry = false;
     }
 }

 void
 SCMasterPort::sendEndReq(tlm::tlm_generic_payload& trans)
 {
     tlm::tlm_phase phase = tlm::END_REQ;
     auto delay = sc_core::SC_ZERO_TIME;

     auto status = transactor->socket->nb_transport_bw(trans, phase, delay);
     panic_if(status != tlm::TLM_ACCEPTED,
              "Unexpected status after sending END_REQ");
 }

 void
 SCMasterPort::b_transport(tlm::tlm_generic_payload& trans,
                         sc_core::sc_time& t)
 {
     Gem5Extension* extension = nullptr;
     trans.get_extension(extension);

     PacketPtr pkt = nullptr;

     // If there is an extension, this transaction was initiated by the gem5
     // world and we can pipe through the original packet.
     if (extension != nullptr) {
         extension->setPipeThrough();
         pkt = extension->getPacket();
     } else {
         pkt = generatePacket(trans);
     }

     Tick ticks = sendAtomic(pkt);

     // send an atomic request to gem5
     panic_if(pkt->needsResponse() && !pkt->isResponse(),
              "Packet sending failed!\n");

     // one tick is a pico second
     auto delay =
       sc_core::sc_time((double)(ticks / SimClock::Int::ps), sc_core::SC_PS);

     // update time
     t += delay;

     if (extension != nullptr)
         destroyPacket(pkt);

     trans.set_response_status(tlm::TLM_OK_RESPONSE);
 }

 unsigned int
 SCMasterPort::transport_dbg(tlm::tlm_generic_payload& trans)
 {
     Gem5Extension* extension = nullptr;
     trans.get_extension(extension);

     // If there is an extension, this transaction was initiated by the gem5
     // world and we can pipe through the original packet.
     if (extension != nullptr) {
         extension->setPipeThrough();
         sendFunctional(extension->getPacket());
     } else {
         auto pkt = generatePacket(trans);
         sendFunctional(pkt);
         destroyPacket(pkt);
     }

     return trans.get_data_length();
 }

 bool
 SCMasterPort::get_direct_mem_ptr(tlm::tlm_generic_payload& trans,
                                tlm::tlm_dmi& dmi_data)
 {
     return false;
 }

 bool
 SCMasterPort::recvTimingResp(PacketPtr pkt)
 {
     // exclusion rule
     // We need to Wait for END_RESP before sending next BEGIN_RESP
     if (responseInProgress) {
         sc_assert(!needToSendRetry);
         needToSendRetry = true;
         return false;
     }

     sc_assert(pkt->isResponse());

     /*
      * Pay for annotated transport delays.
      *
      * See recvTimingReq in sc_slave_port.cc for a detailed description.
      */
     auto delay = sc_core::sc_time::from_value(pkt->payloadDelay);
     // reset the delays
     pkt->payloadDelay = 0;
     pkt->headerDelay = 0;

     auto tlmSenderState = dynamic_cast<TlmSenderState*>(pkt->popSenderState());
     sc_assert(tlmSenderState != nullptr);

     auto& trans = tlmSenderState->trans;

     Gem5Extension* extension = nullptr;
     trans.get_extension(extension);

     // clean up
     delete tlmSenderState;

     // If there is an extension the packet was piped through and we must not
     // delete it. The packet travels back with the transaction.
     if (extension == nullptr)
         destroyPacket(pkt);
     else
         sc_assert(extension->isPipeThrough());

     sendBeginResp(trans, delay);
     trans.release();

     return true;
 }

 void
 SCMasterPort::sendBeginResp(tlm::tlm_generic_payload& trans,
                             sc_core::sc_time& delay)
 {
     tlm::tlm_phase phase = tlm::BEGIN_RESP;

     trans.set_response_status(tlm::TLM_OK_RESPONSE);

     auto status = transactor->socket->nb_transport_bw(trans, phase, delay);

     if (status == tlm::TLM_COMPLETED ||
         status == tlm::TLM_UPDATED && phase == tlm::END_RESP) {
         // transaction completed -> no need to wait for tlm::END_RESP
         responseInProgress = false;
     } else if (status == tlm::TLM_ACCEPTED) {
         // we need to wait for tlm::END_RESP
         responseInProgress = true;
     } else {
         panic("Unexpected status after sending BEGIN_RESP");
     }
 }

 void
 SCMasterPort::recvReqRetry()
 {
     sc_assert(waitForRetry);
     sc_assert(pendingRequest != nullptr);
     sc_assert(pendingPacket != nullptr);

     if (sendTimingReq(pendingPacket)) {
         waitForRetry = false;
         pendingPacket = nullptr;

         auto& trans = *pendingRequest;
         sendEndReq(trans);
         trans.release();

         pendingRequest = nullptr;
     }
 }

 void
 SCMasterPort::recvRangeChange()
 {
     SC_REPORT_WARNING("SCMasterPort",
                       "received address range change but ignored it");
 }

 ExternalMaster::Port*
 SCMasterPortHandler::getExternalPort(const std::string &name,
                                      ExternalMaster &owner,
                                      const std::string &port_data)
 {
     // Create and register a new SystemC master port
     auto* port = new SCMasterPort(name, port_data, owner, control);

     control.registerMasterPort(port_data, port);

     return port;
 }

 } // namespace Gem5SystemC
	/*
	* Copyright (c) 2016, Dresden University of Technology (TU Dresden)
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are
	* met:
	*
	* 1. Redistributions of source code must retain the above copyright notice,
	* this list of conditions and the following disclaimer.
	*
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* 3. Neither the name of the copyright holder nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
	* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER
	* 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; LOSS OF USE, DATA, OR
	* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 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.
	*
	* Authors: Christian Menard
	*/

	#include <sstream>

	#include "master_transactor.hh"
	#include "params/ExternalMaster.hh"
	#include "sc_ext.hh"
	#include "sc_master_port.hh"
	#include "sim/system.hh"

	namespace Gem5SystemC
	{

	PacketPtr
	SCMasterPort::generatePacket(tlm::tlm_generic_payload& trans)
	{
	Request::Flags flags;
	auto req = new Request(trans.get_address(), trans.get_data_length(), flags,
	owner.masterId);

	MemCmd cmd;

	switch (trans.get_command()) {
	case tlm::TLM_READ_COMMAND:
	cmd = MemCmd::ReadReq;
	break;
	case tlm::TLM_WRITE_COMMAND:
	cmd = MemCmd::WriteReq;
	break;
	default:
	SC_REPORT_FATAL("SCMasterPort",
	"received transaction with unsupported command");
	}

	/*
	* Allocate a new Packet. The packet will be deleted when it returns from
	* the gem5 world as a response.
	*/
	auto pkt = new Packet(req, cmd);
	pkt->dataStatic(trans.get_data_ptr());

	return pkt;
	}

	void
	SCMasterPort::destroyPacket(PacketPtr pkt)
	{
	delete pkt;
	}

	SCMasterPort::SCMasterPort(const std::string& name_,
	const std::string& systemc_name,
	ExternalMaster& owner_,
	Gem5SimControl& simControl)
	: ExternalMaster::Port(name_, owner_),
	peq(this, &SCMasterPort::peq_cb),
	waitForRetry(false),
	pendingRequest(nullptr),
	pendingPacket(nullptr),
	needToSendRetry(false),
	responseInProgress(false),
	transactor(nullptr),
	simControl(simControl)
	{
	system =
	dynamic_cast<const ExternalMasterParams*>(owner_.params())->system;
	}

	void
	SCMasterPort::bindToTransactor(Gem5MasterTransactor* transactor)
	{
	sc_assert(this->transactor == nullptr);

	this->transactor = transactor;

	/*
	* Register the TLM non-blocking interface when using gem5 Timing mode and
	* the TLM blocking interface when using the gem5 Atomic mode.
	* Then the magic (TM) in simple_target_socket automatically transforms
	* non-blocking in blocking transactions and vice versa.
	*
	* NOTE: The mode may change during execution.
	*/
	if (system->isTimingMode()) {
	SC_REPORT_INFO("SCMasterPort", "register non-blocking interface");
	transactor->socket.register_nb_transport_fw(this,
	&SCMasterPort::nb_transport_fw);
	} else if (system->isAtomicMode()) {
	SC_REPORT_INFO("SCMasterPort", "register blocking interface");
	transactor->socket.register_b_transport(this,
	&SCMasterPort::b_transport);
	} else {
	panic("gem5 operates neither in Timing nor in Atomic mode");
	}

	transactor->socket.register_transport_dbg(this,
	&SCMasterPort::transport_dbg);
	}

	void
	SCMasterPort::checkTransaction(tlm::tlm_generic_payload& trans)
	{
	if (trans.is_response_error()) {
	std::stringstream ss;
	ss << "Transaction returned with error, response status = "
	<< trans.get_response_string();
	SC_REPORT_ERROR("TLM-2", ss.str().c_str());
	}
	}

	tlm::tlm_sync_enum
	SCMasterPort::nb_transport_fw(tlm::tlm_generic_payload& trans,
	tlm::tlm_phase& phase, sc_core::sc_time& delay)
	{
	uint64_t adr = trans.get_address();
	unsigned len = trans.get_data_length();
	unsigned char* byteEnable = trans.get_byte_enable_ptr();
	unsigned width = trans.get_streaming_width();

	// check the transaction attributes for unsupported features ...
	if (byteEnable != 0) {
	trans.set_response_status(tlm::TLM_BYTE_ENABLE_ERROR_RESPONSE);
	return tlm::TLM_COMPLETED;
	}
	if (width < len) { // is this a burst request?
	trans.set_response_status(tlm::TLM_BURST_ERROR_RESPONSE);
	return tlm::TLM_COMPLETED;
	}

	// ... and queue the valid transaction
	trans.acquire();
	peq.notify(trans, phase, delay);
	return tlm::TLM_ACCEPTED;
	}

	void
	SCMasterPort::peq_cb(tlm::tlm_generic_payload& trans,
	const tlm::tlm_phase& phase)
	{
	// catch up with SystemC time
	simControl.catchup();
	assert(curTick() == sc_core::sc_time_stamp().value());

	switch (phase) {
	case tlm::BEGIN_REQ:
	handleBeginReq(trans);
	break;
	case tlm::END_RESP:
	handleEndResp(trans);
	break;
	default:
	panic("unimplemented phase in callback");
	}

	// the functions called above may have scheduled gem5 events
	// -> notify the event loop handler
	simControl.notify();
	}

	void
	SCMasterPort::handleBeginReq(tlm::tlm_generic_payload& trans)
	{
	sc_assert(!waitForRetry);
	sc_assert(pendingRequest == nullptr);
	sc_assert(pendingPacket == nullptr);

	trans.acquire();

	PacketPtr pkt = nullptr;

	Gem5Extension* extension = nullptr;
	trans.get_extension(extension);

	// If there is an extension, this transaction was initiated by the gem5
	// world and we can pipe through the original packet. Otherwise, we
	// generate a new packet based on the transaction.
	if (extension != nullptr) {
	extension->setPipeThrough();
	pkt = extension->getPacket();
	} else {
	pkt = generatePacket(trans);
	}

	auto tlmSenderState = new TlmSenderState(trans);
	pkt->pushSenderState(tlmSenderState);

	if (sendTimingReq(pkt)) { // port is free -> send END_REQ immediately
	sendEndReq(trans);
	trans.release();
	} else { // port is blocked -> wait for retry before sending END_REQ
	waitForRetry = true;
	pendingRequest = &trans;
	pendingPacket = pkt;
	}
	}

	void
	SCMasterPort::handleEndResp(tlm::tlm_generic_payload& trans)
	{
	sc_assert(responseInProgress);

	responseInProgress = false;

	checkTransaction(trans);

	if (needToSendRetry) {
	sendRetryResp();
	needToSendRetry = false;
	}
	}

	void
	SCMasterPort::sendEndReq(tlm::tlm_generic_payload& trans)
	{
	tlm::tlm_phase phase = tlm::END_REQ;
	auto delay = sc_core::SC_ZERO_TIME;

	auto status = transactor->socket->nb_transport_bw(trans, phase, delay);
	panic_if(status != tlm::TLM_ACCEPTED,
	"Unexpected status after sending END_REQ");
	}

	void
	SCMasterPort::b_transport(tlm::tlm_generic_payload& trans,
	sc_core::sc_time& t)
	{
	Gem5Extension* extension = nullptr;
	trans.get_extension(extension);

	PacketPtr pkt = nullptr;

	// If there is an extension, this transaction was initiated by the gem5
	// world and we can pipe through the original packet.
	if (extension != nullptr) {
	extension->setPipeThrough();
	pkt = extension->getPacket();
	} else {
	pkt = generatePacket(trans);
	}

	Tick ticks = sendAtomic(pkt);

	// send an atomic request to gem5
	panic_if(pkt->needsResponse() && !pkt->isResponse(),
	"Packet sending failed!\n");

	// one tick is a pico second
	auto delay =
	sc_core::sc_time((double)(ticks / SimClock::Int::ps), sc_core::SC_PS);

	// update time
	t += delay;

	if (extension != nullptr)
	destroyPacket(pkt);

	trans.set_response_status(tlm::TLM_OK_RESPONSE);
	}

	unsigned int
	SCMasterPort::transport_dbg(tlm::tlm_generic_payload& trans)
	{
	Gem5Extension* extension = nullptr;
	trans.get_extension(extension);

	// If there is an extension, this transaction was initiated by the gem5
	// world and we can pipe through the original packet.
	if (extension != nullptr) {
	extension->setPipeThrough();
	sendFunctional(extension->getPacket());
	} else {
	auto pkt = generatePacket(trans);
	sendFunctional(pkt);
	destroyPacket(pkt);
	}

	return trans.get_data_length();
	}

	bool
	SCMasterPort::get_direct_mem_ptr(tlm::tlm_generic_payload& trans,
	tlm::tlm_dmi& dmi_data)
	{
	return false;
	}

	bool
	SCMasterPort::recvTimingResp(PacketPtr pkt)
	{
	// exclusion rule
	// We need to Wait for END_RESP before sending next BEGIN_RESP
	if (responseInProgress) {
	sc_assert(!needToSendRetry);
	needToSendRetry = true;
	return false;
	}

	sc_assert(pkt->isResponse());

	/*
	* Pay for annotated transport delays.
	*
	* See recvTimingReq in sc_slave_port.cc for a detailed description.
	*/
	auto delay = sc_core::sc_time::from_value(pkt->payloadDelay);
	// reset the delays
	pkt->payloadDelay = 0;
	pkt->headerDelay = 0;

	auto tlmSenderState = dynamic_cast<TlmSenderState*>(pkt->popSenderState());
	sc_assert(tlmSenderState != nullptr);

	auto& trans = tlmSenderState->trans;

	Gem5Extension* extension = nullptr;
	trans.get_extension(extension);

	// clean up
	delete tlmSenderState;

	// If there is an extension the packet was piped through and we must not
	// delete it. The packet travels back with the transaction.
	if (extension == nullptr)
	destroyPacket(pkt);
	else
	sc_assert(extension->isPipeThrough());

	sendBeginResp(trans, delay);
	trans.release();

	return true;
	}

	void
	SCMasterPort::sendBeginResp(tlm::tlm_generic_payload& trans,
	sc_core::sc_time& delay)
	{
	tlm::tlm_phase phase = tlm::BEGIN_RESP;

	trans.set_response_status(tlm::TLM_OK_RESPONSE);

	auto status = transactor->socket->nb_transport_bw(trans, phase, delay);

	if (status == tlm::TLM_COMPLETED \|\|
	status == tlm::TLM_UPDATED && phase == tlm::END_RESP) {
	// transaction completed -> no need to wait for tlm::END_RESP
	responseInProgress = false;
	} else if (status == tlm::TLM_ACCEPTED) {
	// we need to wait for tlm::END_RESP
	responseInProgress = true;
	} else {
	panic("Unexpected status after sending BEGIN_RESP");
	}
	}

	void
	SCMasterPort::recvReqRetry()
	{
	sc_assert(waitForRetry);
	sc_assert(pendingRequest != nullptr);
	sc_assert(pendingPacket != nullptr);

	if (sendTimingReq(pendingPacket)) {
	waitForRetry = false;
	pendingPacket = nullptr;

	auto& trans = *pendingRequest;
	sendEndReq(trans);
	trans.release();

	pendingRequest = nullptr;
	}
	}

	void
	SCMasterPort::recvRangeChange()
	{
	SC_REPORT_WARNING("SCMasterPort",
	"received address range change but ignored it");
	}

	ExternalMaster::Port*
	SCMasterPortHandler::getExternalPort(const std::string &name,
	ExternalMaster &owner,
	const std::string &port_data)
	{
	// Create and register a new SystemC master port
	auto* port = new SCMasterPort(name, port_data, owner, control);

	control.registerMasterPort(port_data, port);

	return port;
	}

	} // namespace Gem5SystemC