InputUnit.cc revision 11666
111666Stushar@ece.gatech.edu/* 211666Stushar@ece.gatech.edu * Copyright (c) 2008 Princeton University 311666Stushar@ece.gatech.edu * Copyright (c) 2016 Georgia Institute of Technology 411666Stushar@ece.gatech.edu * All rights reserved. 511666Stushar@ece.gatech.edu * 611666Stushar@ece.gatech.edu * Redistribution and use in source and binary forms, with or without 711666Stushar@ece.gatech.edu * modification, are permitted provided that the following conditions are 811666Stushar@ece.gatech.edu * met: redistributions of source code must retain the above copyright 911666Stushar@ece.gatech.edu * notice, this list of conditions and the following disclaimer; 1011666Stushar@ece.gatech.edu * redistributions in binary form must reproduce the above copyright 1111666Stushar@ece.gatech.edu * notice, this list of conditions and the following disclaimer in the 1211666Stushar@ece.gatech.edu * documentation and/or other materials provided with the distribution; 1311666Stushar@ece.gatech.edu * neither the name of the copyright holders nor the names of its 1411666Stushar@ece.gatech.edu * contributors may be used to endorse or promote products derived from 1511666Stushar@ece.gatech.edu * this software without specific prior written permission. 1611666Stushar@ece.gatech.edu * 1711666Stushar@ece.gatech.edu * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 1811666Stushar@ece.gatech.edu * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 1911666Stushar@ece.gatech.edu * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 2011666Stushar@ece.gatech.edu * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 2111666Stushar@ece.gatech.edu * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 2211666Stushar@ece.gatech.edu * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 2311666Stushar@ece.gatech.edu * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 2411666Stushar@ece.gatech.edu * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 2511666Stushar@ece.gatech.edu * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 2611666Stushar@ece.gatech.edu * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 2711666Stushar@ece.gatech.edu * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 2811666Stushar@ece.gatech.edu * 2911666Stushar@ece.gatech.edu * Authors: Niket Agarwal 3011666Stushar@ece.gatech.edu * Tushar Krishna 3111666Stushar@ece.gatech.edu */ 3211666Stushar@ece.gatech.edu 3311666Stushar@ece.gatech.edu 3411666Stushar@ece.gatech.edu#include "mem/ruby/network/garnet2.0/InputUnit.hh" 3511666Stushar@ece.gatech.edu 3611666Stushar@ece.gatech.edu#include "base/stl_helpers.hh" 3711666Stushar@ece.gatech.edu#include "debug/RubyNetwork.hh" 3811666Stushar@ece.gatech.edu#include "mem/ruby/network/garnet2.0/Credit.hh" 3911666Stushar@ece.gatech.edu#include "mem/ruby/network/garnet2.0/Router.hh" 4011666Stushar@ece.gatech.edu 4111666Stushar@ece.gatech.eduusing namespace std; 4211666Stushar@ece.gatech.eduusing m5::stl_helpers::deletePointers; 4311666Stushar@ece.gatech.edu 4411666Stushar@ece.gatech.eduInputUnit::InputUnit(int id, PortDirection direction, Router *router) 4511666Stushar@ece.gatech.edu : Consumer(router) 4611666Stushar@ece.gatech.edu{ 4711666Stushar@ece.gatech.edu m_id = id; 4811666Stushar@ece.gatech.edu m_direction = direction; 4911666Stushar@ece.gatech.edu m_router = router; 5011666Stushar@ece.gatech.edu m_num_vcs = m_router->get_num_vcs(); 5111666Stushar@ece.gatech.edu m_vc_per_vnet = m_router->get_vc_per_vnet(); 5211666Stushar@ece.gatech.edu 5311666Stushar@ece.gatech.edu m_num_buffer_reads.resize(m_num_vcs/m_vc_per_vnet); 5411666Stushar@ece.gatech.edu m_num_buffer_writes.resize(m_num_vcs/m_vc_per_vnet); 5511666Stushar@ece.gatech.edu for (int i = 0; i < m_num_buffer_reads.size(); i++) { 5611666Stushar@ece.gatech.edu m_num_buffer_reads[i] = 0; 5711666Stushar@ece.gatech.edu m_num_buffer_writes[i] = 0; 5811666Stushar@ece.gatech.edu } 5911666Stushar@ece.gatech.edu 6011666Stushar@ece.gatech.edu creditQueue = new flitBuffer(); 6111666Stushar@ece.gatech.edu // Instantiating the virtual channels 6211666Stushar@ece.gatech.edu m_vcs.resize(m_num_vcs); 6311666Stushar@ece.gatech.edu for (int i=0; i < m_num_vcs; i++) { 6411666Stushar@ece.gatech.edu m_vcs[i] = new VirtualChannel(i); 6511666Stushar@ece.gatech.edu } 6611666Stushar@ece.gatech.edu} 6711666Stushar@ece.gatech.edu 6811666Stushar@ece.gatech.eduInputUnit::~InputUnit() 6911666Stushar@ece.gatech.edu{ 7011666Stushar@ece.gatech.edu delete creditQueue; 7111666Stushar@ece.gatech.edu deletePointers(m_vcs); 7211666Stushar@ece.gatech.edu} 7311666Stushar@ece.gatech.edu 7411666Stushar@ece.gatech.edu/* 7511666Stushar@ece.gatech.edu * The InputUnit wakeup function reads the input flit from its input link. 7611666Stushar@ece.gatech.edu * Each flit arrives with an input VC. 7711666Stushar@ece.gatech.edu * For HEAD/HEAD_TAIL flits, performs route computation, 7811666Stushar@ece.gatech.edu * and updates route in the input VC. 7911666Stushar@ece.gatech.edu * The flit is buffered for (m_latency - 1) cycles in the input VC 8011666Stushar@ece.gatech.edu * and marked as valid for SwitchAllocation starting that cycle. 8111666Stushar@ece.gatech.edu * 8211666Stushar@ece.gatech.edu */ 8311666Stushar@ece.gatech.edu 8411666Stushar@ece.gatech.eduvoid 8511666Stushar@ece.gatech.eduInputUnit::wakeup() 8611666Stushar@ece.gatech.edu{ 8711666Stushar@ece.gatech.edu flit *t_flit; 8811666Stushar@ece.gatech.edu if (m_in_link->isReady(m_router->curCycle())) { 8911666Stushar@ece.gatech.edu 9011666Stushar@ece.gatech.edu t_flit = m_in_link->consumeLink(); 9111666Stushar@ece.gatech.edu int vc = t_flit->get_vc(); 9211666Stushar@ece.gatech.edu t_flit->increment_hops(); // for stats 9311666Stushar@ece.gatech.edu 9411666Stushar@ece.gatech.edu if ((t_flit->get_type() == HEAD_) || 9511666Stushar@ece.gatech.edu (t_flit->get_type() == HEAD_TAIL_)) { 9611666Stushar@ece.gatech.edu 9711666Stushar@ece.gatech.edu assert(m_vcs[vc]->get_state() == IDLE_); 9811666Stushar@ece.gatech.edu set_vc_active(vc, m_router->curCycle()); 9911666Stushar@ece.gatech.edu 10011666Stushar@ece.gatech.edu // Route computation for this vc 10111666Stushar@ece.gatech.edu int outport = m_router->route_compute(t_flit->get_route(), 10211666Stushar@ece.gatech.edu m_id, m_direction); 10311666Stushar@ece.gatech.edu 10411666Stushar@ece.gatech.edu // Update output port in VC 10511666Stushar@ece.gatech.edu // All flits in this packet will use this output port 10611666Stushar@ece.gatech.edu // The output port field in the flit is updated after it wins SA 10711666Stushar@ece.gatech.edu grant_outport(vc, outport); 10811666Stushar@ece.gatech.edu 10911666Stushar@ece.gatech.edu } else { 11011666Stushar@ece.gatech.edu assert(m_vcs[vc]->get_state() == ACTIVE_); 11111666Stushar@ece.gatech.edu } 11211666Stushar@ece.gatech.edu 11311666Stushar@ece.gatech.edu 11411666Stushar@ece.gatech.edu // Buffer the flit 11511666Stushar@ece.gatech.edu m_vcs[vc]->insertFlit(t_flit); 11611666Stushar@ece.gatech.edu 11711666Stushar@ece.gatech.edu int vnet = vc/m_vc_per_vnet; 11811666Stushar@ece.gatech.edu // number of writes same as reads 11911666Stushar@ece.gatech.edu // any flit that is written will be read only once 12011666Stushar@ece.gatech.edu m_num_buffer_writes[vnet]++; 12111666Stushar@ece.gatech.edu m_num_buffer_reads[vnet]++; 12211666Stushar@ece.gatech.edu 12311666Stushar@ece.gatech.edu Cycles pipe_stages = m_router->get_pipe_stages(); 12411666Stushar@ece.gatech.edu if (pipe_stages == 1) { 12511666Stushar@ece.gatech.edu // 1-cycle router 12611666Stushar@ece.gatech.edu // Flit goes for SA directly 12711666Stushar@ece.gatech.edu t_flit->advance_stage(SA_, m_router->curCycle()); 12811666Stushar@ece.gatech.edu } else { 12911666Stushar@ece.gatech.edu assert(pipe_stages > 1); 13011666Stushar@ece.gatech.edu // Router delay is modeled by making flit wait in buffer for 13111666Stushar@ece.gatech.edu // (pipe_stages cycles - 1) cycles before going for SA 13211666Stushar@ece.gatech.edu 13311666Stushar@ece.gatech.edu Cycles wait_time = pipe_stages - Cycles(1); 13411666Stushar@ece.gatech.edu t_flit->advance_stage(SA_, m_router->curCycle() + wait_time); 13511666Stushar@ece.gatech.edu 13611666Stushar@ece.gatech.edu // Wakeup the router in that cycle to perform SA 13711666Stushar@ece.gatech.edu m_router->schedule_wakeup(Cycles(wait_time)); 13811666Stushar@ece.gatech.edu } 13911666Stushar@ece.gatech.edu } 14011666Stushar@ece.gatech.edu} 14111666Stushar@ece.gatech.edu 14211666Stushar@ece.gatech.edu// Send a credit back to upstream router for this VC. 14311666Stushar@ece.gatech.edu// Called by SwitchAllocator when the flit in this VC wins the Switch. 14411666Stushar@ece.gatech.eduvoid 14511666Stushar@ece.gatech.eduInputUnit::increment_credit(int in_vc, bool free_signal, Cycles curTime) 14611666Stushar@ece.gatech.edu{ 14711666Stushar@ece.gatech.edu Credit *t_credit = new Credit(in_vc, free_signal, curTime); 14811666Stushar@ece.gatech.edu creditQueue->insert(t_credit); 14911666Stushar@ece.gatech.edu m_credit_link->scheduleEventAbsolute(m_router->clockEdge(Cycles(1))); 15011666Stushar@ece.gatech.edu} 15111666Stushar@ece.gatech.edu 15211666Stushar@ece.gatech.edu 15311666Stushar@ece.gatech.eduuint32_t 15411666Stushar@ece.gatech.eduInputUnit::functionalWrite(Packet *pkt) 15511666Stushar@ece.gatech.edu{ 15611666Stushar@ece.gatech.edu uint32_t num_functional_writes = 0; 15711666Stushar@ece.gatech.edu for (int i=0; i < m_num_vcs; i++) { 15811666Stushar@ece.gatech.edu num_functional_writes += m_vcs[i]->functionalWrite(pkt); 15911666Stushar@ece.gatech.edu } 16011666Stushar@ece.gatech.edu 16111666Stushar@ece.gatech.edu return num_functional_writes; 16211666Stushar@ece.gatech.edu} 16311666Stushar@ece.gatech.edu 16411666Stushar@ece.gatech.eduvoid 16511666Stushar@ece.gatech.eduInputUnit::resetStats() 16611666Stushar@ece.gatech.edu{ 16711666Stushar@ece.gatech.edu for (int j = 0; j < m_num_buffer_reads.size(); j++) { 16811666Stushar@ece.gatech.edu m_num_buffer_reads[j] = 0; 16911666Stushar@ece.gatech.edu m_num_buffer_writes[j] = 0; 17011666Stushar@ece.gatech.edu } 17111666Stushar@ece.gatech.edu} 172