/*
 * Copyright (c) 2008 Princeton University
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met: redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer;
 * 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;
 * neither the name of the copyright holders 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
 * OWNER 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: Niket Agarwal
 */

#include "base/stl_helpers.hh"
#include "mem/ruby/network/garnet/fixed-pipeline/InputUnit_d.hh"
#include "mem/ruby/network/garnet/fixed-pipeline/Router_d.hh"

using namespace std;
using m5::stl_helpers::deletePointers;

InputUnit_d::InputUnit_d(int id, Router_d *router)
{
    m_id = id;
    m_router = router;
    m_num_vcs = m_router->get_num_vcs();
    m_vc_per_vnet = m_router->get_vc_per_vnet();

    m_num_buffer_reads.resize(m_num_vcs/m_vc_per_vnet);
    m_num_buffer_writes.resize(m_num_vcs/m_vc_per_vnet);
    for (int i = 0; i < m_num_buffer_reads.size(); i++) {
        m_num_buffer_reads[i] = 0;
        m_num_buffer_writes[i] = 0;
    }

    creditQueue = new flitBuffer_d();
    // Instantiating the virtual channels
    m_vcs.resize(m_num_vcs);
    for (int i=0; i < m_num_vcs; i++) {
        m_vcs[i] = new VirtualChannel_d(i);
    }
}

InputUnit_d::~InputUnit_d()
{
    delete creditQueue;
    deletePointers(m_vcs);
}

void
InputUnit_d::wakeup()
{
    flit_d *t_flit;
    if (m_in_link->isReady()) {

        t_flit = m_in_link->consumeLink();
        int vc = t_flit->get_vc();

        if ((t_flit->get_type() == HEAD_) ||
           (t_flit->get_type() == HEAD_TAIL_)) {

            assert(m_vcs[vc]->get_state() == IDLE_);
            // Do the route computation for this vc
            m_router->route_req(t_flit, this, vc);

            m_vcs[vc]->set_enqueue_time(g_system_ptr->getTime());
        } else {
            t_flit->advance_stage(SA_);
            m_router->swarb_req();
        }
        // write flit into input buffer
        m_vcs[vc]->insertFlit(t_flit);

        int vnet = vc/m_vc_per_vnet;
        // number of writes same as reads
        // any flit that is written will be read only once
        m_num_buffer_writes[vnet]++;
        m_num_buffer_reads[vnet]++;
    }
}