xref: /gem5/src/systemc/tests/include/SimpleBusLT.h

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  more contributor license agreements.  See the NOTICE file distributed
  with this work for additional information regarding copyright ownership.
  Accellera licenses this file to you under the Apache License, Version 2.0
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#ifndef __SIMPLEBUSLT_H__
#define __SIMPLEBUSLT_H__

//#include <systemc>
#include "tlm.h"

#include "tlm_utils/simple_target_socket.h"
#include "tlm_utils/simple_initiator_socket.h"

template <int NR_OF_INITIATORS, int NR_OF_TARGETS>
class SimpleBusLT : public sc_core::sc_module
{
public:
  typedef tlm::tlm_generic_payload                 transaction_type;
  typedef tlm::tlm_phase                           phase_type;
  typedef tlm::tlm_sync_enum                       sync_enum_type;
  typedef tlm_utils::simple_target_socket_tagged<SimpleBusLT>    target_socket_type;
  typedef tlm_utils::simple_initiator_socket_tagged<SimpleBusLT> initiator_socket_type;

public:
  target_socket_type target_socket[NR_OF_INITIATORS];
  initiator_socket_type initiator_socket[NR_OF_TARGETS];

public:
  SC_HAS_PROCESS(SimpleBusLT);
  SimpleBusLT(sc_core::sc_module_name name) :
    sc_core::sc_module(name)
  {
    for (unsigned int i = 0; i < NR_OF_INITIATORS; ++i) {
      target_socket[i].register_b_transport(this, &SimpleBusLT::initiatorBTransport, i);
      target_socket[i].register_transport_dbg(this, &SimpleBusLT::transportDebug, i);
      target_socket[i].register_get_direct_mem_ptr(this, &SimpleBusLT::getDMIPointer, i);
    }
    for (unsigned int i = 0; i < NR_OF_TARGETS; ++i) {
      initiator_socket[i].register_invalidate_direct_mem_ptr(this, &SimpleBusLT::invalidateDMIPointers, i);
    }
  }

  //
  // Dummy decoder:
  // - address[31-28]: portId
  // - address[27-0]: masked address
  //

  unsigned int getPortId(const sc_dt::uint64& address)
  {
    return (unsigned int)address >> 28;
  }

  sc_dt::uint64 getAddressOffset(unsigned int portId)
  {
    return portId << 28;
  }

  sc_dt::uint64 getAddressMask(unsigned int portId)
  {
    return 0xfffffff;
  }

  unsigned int decode(const sc_dt::uint64& address)
  {
    // decode address:
    // - return initiator socket id

    return getPortId(address);
  }

  //
  // interface methods
  //

  //
  // LT protocol
  // - forward each call to the target/initiator
  //
  void initiatorBTransport(int SocketId,
                           transaction_type& trans,
                           sc_core::sc_time& t)
  {
    initiator_socket_type* decodeSocket;
    unsigned int portId = decode(trans.get_address());
    assert(portId < NR_OF_TARGETS);
    decodeSocket = &initiator_socket[portId];
    trans.set_address(trans.get_address() & getAddressMask(portId));

    (*decodeSocket)->b_transport(trans, t);
  }

  unsigned int transportDebug(int SocketId,
                              transaction_type& trans)
  {
    unsigned int portId = decode(trans.get_address());
    assert(portId < NR_OF_TARGETS);
    initiator_socket_type* decodeSocket = &initiator_socket[portId];
    trans.set_address( trans.get_address() & getAddressMask(portId) );

    return (*decodeSocket)->transport_dbg(trans);
  }

  bool limitRange(unsigned int portId, sc_dt::uint64& low, sc_dt::uint64& high)
  {
    sc_dt::uint64 addressOffset = getAddressOffset(portId);
    sc_dt::uint64 addressMask = getAddressMask(portId);

    if (low > addressMask) {
      // Range does not overlap with addressrange for this target
      return false;
    }

    low += addressOffset;
    if (high > addressMask) {
      high = addressOffset + addressMask;

    } else {
      high += addressOffset;
    }
    return true;
  }

  bool getDMIPointer(int SocketId,
                     transaction_type& trans,
                     tlm::tlm_dmi&  dmi_data)
  {
    sc_dt::uint64 address = trans.get_address();

    unsigned int portId = decode(address);
    assert(portId < NR_OF_TARGETS);
    initiator_socket_type* decodeSocket = &initiator_socket[portId];
    sc_dt::uint64 maskedAddress = address & getAddressMask(portId);

    trans.set_address(maskedAddress);

    bool result =
      (*decodeSocket)->get_direct_mem_ptr(trans, dmi_data);

    if (result)
    {
      // Range must contain address
      assert(dmi_data.get_start_address() <= maskedAddress);
      assert(dmi_data.get_end_address() >= maskedAddress);
    }

    // Should always succeed
	sc_dt::uint64 start, end;
	start = dmi_data.get_start_address();
	end = dmi_data.get_end_address();

	limitRange(portId, start, end);

	dmi_data.set_start_address(start);
	dmi_data.set_end_address(end);

    return result;
  }

  void invalidateDMIPointers(int port_id,
                             sc_dt::uint64 start_range,
                             sc_dt::uint64 end_range)
  {
    // FIXME: probably faster to always invalidate everything?

    if (!limitRange(port_id, start_range, end_range)) {
      // Range does not fall into address range of target
      return;
    }

    for (unsigned int i = 0; i < NR_OF_INITIATORS; ++i) {
      (target_socket[i])->invalidate_direct_mem_ptr(start_range, end_range);
    }
  }

};

#endif