coherent_xbar.cc revision 11190
12497SN/A/* 210719SMarco.Balboni@ARM.com * Copyright (c) 2011-2015 ARM Limited 38711SN/A * All rights reserved 48711SN/A * 58711SN/A * The license below extends only to copyright in the software and shall 68711SN/A * not be construed as granting a license to any other intellectual 78711SN/A * property including but not limited to intellectual property relating 88711SN/A * to a hardware implementation of the functionality of the software 98711SN/A * licensed hereunder. You may use the software subject to the license 108711SN/A * terms below provided that you ensure that this notice is replicated 118711SN/A * unmodified and in its entirety in all distributions of the software, 128711SN/A * modified or unmodified, in source code or in binary form. 138711SN/A * 142497SN/A * Copyright (c) 2006 The Regents of The University of Michigan 152497SN/A * All rights reserved. 162497SN/A * 172497SN/A * Redistribution and use in source and binary forms, with or without 182497SN/A * modification, are permitted provided that the following conditions are 192497SN/A * met: redistributions of source code must retain the above copyright 202497SN/A * notice, this list of conditions and the following disclaimer; 212497SN/A * redistributions in binary form must reproduce the above copyright 222497SN/A * notice, this list of conditions and the following disclaimer in the 232497SN/A * documentation and/or other materials provided with the distribution; 242497SN/A * neither the name of the copyright holders nor the names of its 252497SN/A * contributors may be used to endorse or promote products derived from 262497SN/A * this software without specific prior written permission. 272497SN/A * 282497SN/A * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 292497SN/A * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 302497SN/A * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 312497SN/A * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 322497SN/A * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 332497SN/A * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 342497SN/A * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 352497SN/A * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 362497SN/A * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 372497SN/A * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 382497SN/A * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 392665SN/A * 402665SN/A * Authors: Ali Saidi 418715SN/A * Andreas Hansson 428922SN/A * William Wang 432497SN/A */ 442497SN/A 452497SN/A/** 462982SN/A * @file 4710405Sandreas.hansson@arm.com * Definition of a crossbar object. 482497SN/A */ 492497SN/A 502846SN/A#include "base/misc.hh" 512548SN/A#include "base/trace.hh" 5210405Sandreas.hansson@arm.com#include "debug/AddrRanges.hh" 5310405Sandreas.hansson@arm.com#include "debug/CoherentXBar.hh" 5410405Sandreas.hansson@arm.com#include "mem/coherent_xbar.hh" 559524SN/A#include "sim/system.hh" 562497SN/A 5710405Sandreas.hansson@arm.comCoherentXBar::CoherentXBar(const CoherentXBarParams *p) 5810719SMarco.Balboni@ARM.com : BaseXBar(p), system(p->system), snoopFilter(p->snoop_filter), 5910719SMarco.Balboni@ARM.com snoopResponseLatency(p->snoop_response_latency) 607523SN/A{ 618851SN/A // create the ports based on the size of the master and slave 628948SN/A // vector ports, and the presence of the default port, the ports 638948SN/A // are enumerated starting from zero 648851SN/A for (int i = 0; i < p->port_master_connection_count; ++i) { 659095SN/A std::string portName = csprintf("%s.master[%d]", name(), i); 6610405Sandreas.hansson@arm.com MasterPort* bp = new CoherentXBarMasterPort(portName, *this, i); 678922SN/A masterPorts.push_back(bp); 689715SN/A reqLayers.push_back(new ReqLayer(*bp, *this, 699715SN/A csprintf(".reqLayer%d", i))); 7010713Sandreas.hansson@arm.com snoopLayers.push_back(new SnoopRespLayer(*bp, *this, 7110713Sandreas.hansson@arm.com csprintf(".snoopLayer%d", i))); 728851SN/A } 738851SN/A 748948SN/A // see if we have a default slave device connected and if so add 758948SN/A // our corresponding master port 768915SN/A if (p->port_default_connection_count) { 779031SN/A defaultPortID = masterPorts.size(); 789095SN/A std::string portName = name() + ".default"; 7910405Sandreas.hansson@arm.com MasterPort* bp = new CoherentXBarMasterPort(portName, *this, 809036SN/A defaultPortID); 818922SN/A masterPorts.push_back(bp); 829715SN/A reqLayers.push_back(new ReqLayer(*bp, *this, csprintf(".reqLayer%d", 839715SN/A defaultPortID))); 8410713Sandreas.hansson@arm.com snoopLayers.push_back(new SnoopRespLayer(*bp, *this, 8510713Sandreas.hansson@arm.com csprintf(".snoopLayer%d", 8610713Sandreas.hansson@arm.com defaultPortID))); 878915SN/A } 888915SN/A 898948SN/A // create the slave ports, once again starting at zero 908851SN/A for (int i = 0; i < p->port_slave_connection_count; ++i) { 919095SN/A std::string portName = csprintf("%s.slave[%d]", name(), i); 9210888Sandreas.hansson@arm.com QueuedSlavePort* bp = new CoherentXBarSlavePort(portName, *this, i); 938922SN/A slavePorts.push_back(bp); 949715SN/A respLayers.push_back(new RespLayer(*bp, *this, 959715SN/A csprintf(".respLayer%d", i))); 969716SN/A snoopRespPorts.push_back(new SnoopRespPort(*bp, *this)); 978851SN/A } 988851SN/A 997523SN/A clearPortCache(); 1007523SN/A} 1017523SN/A 10210405Sandreas.hansson@arm.comCoherentXBar::~CoherentXBar() 1039715SN/A{ 10410405Sandreas.hansson@arm.com for (auto l: reqLayers) 10510405Sandreas.hansson@arm.com delete l; 10610405Sandreas.hansson@arm.com for (auto l: respLayers) 10710405Sandreas.hansson@arm.com delete l; 10810405Sandreas.hansson@arm.com for (auto l: snoopLayers) 10910405Sandreas.hansson@arm.com delete l; 11010405Sandreas.hansson@arm.com for (auto p: snoopRespPorts) 11110405Sandreas.hansson@arm.com delete p; 1129715SN/A} 1139715SN/A 1142568SN/Avoid 11510405Sandreas.hansson@arm.comCoherentXBar::init() 1162568SN/A{ 1179278SN/A // the base class is responsible for determining the block size 11810405Sandreas.hansson@arm.com BaseXBar::init(); 1199278SN/A 1208948SN/A // iterate over our slave ports and determine which of our 1218948SN/A // neighbouring master ports are snooping and add them as snoopers 12210405Sandreas.hansson@arm.com for (const auto& p: slavePorts) { 1239088SN/A // check if the connected master port is snooping 12410405Sandreas.hansson@arm.com if (p->isSnooping()) { 12510405Sandreas.hansson@arm.com DPRINTF(AddrRanges, "Adding snooping master %s\n", 12610405Sandreas.hansson@arm.com p->getMasterPort().name()); 12710405Sandreas.hansson@arm.com snoopPorts.push_back(p); 1288711SN/A } 1298711SN/A } 1302568SN/A 1319036SN/A if (snoopPorts.empty()) 13210405Sandreas.hansson@arm.com warn("CoherentXBar %s has no snooping ports attached!\n", name()); 13311133Sandreas.hansson@arm.com 13411133Sandreas.hansson@arm.com // inform the snoop filter about the slave ports so it can create 13511133Sandreas.hansson@arm.com // its own internal representation 13611133Sandreas.hansson@arm.com if (snoopFilter) 13711133Sandreas.hansson@arm.com snoopFilter->setSlavePorts(slavePorts); 1383244SN/A} 1393244SN/A 1408948SN/Abool 14110405Sandreas.hansson@arm.comCoherentXBar::recvTimingReq(PacketPtr pkt, PortID slave_port_id) 1423244SN/A{ 1438975SN/A // determine the source port based on the id 1449032SN/A SlavePort *src_port = slavePorts[slave_port_id]; 1453244SN/A 1469091SN/A // remember if the packet is an express snoop 1479091SN/A bool is_express_snoop = pkt->isExpressSnoop(); 14810656Sandreas.hansson@arm.com bool is_inhibited = pkt->memInhibitAsserted(); 14910656Sandreas.hansson@arm.com // for normal requests, going downstream, the express snoop flag 15010656Sandreas.hansson@arm.com // and the inhibited flag should always be the same 15110656Sandreas.hansson@arm.com assert(is_express_snoop == is_inhibited); 1529091SN/A 1539612SN/A // determine the destination based on the address 1549712SN/A PortID master_port_id = findPort(pkt->getAddr()); 1559612SN/A 15610405Sandreas.hansson@arm.com // test if the crossbar should be considered occupied for the current 1579033SN/A // port, and exclude express snoops from the check 1589715SN/A if (!is_express_snoop && !reqLayers[master_port_id]->tryTiming(src_port)) { 15910405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingReq: src %s %s 0x%x BUSY\n", 1608949SN/A src_port->name(), pkt->cmdString(), pkt->getAddr()); 1613244SN/A return false; 1623244SN/A } 1633244SN/A 16410405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingReq: src %s %s expr %d 0x%x\n", 1659091SN/A src_port->name(), pkt->cmdString(), is_express_snoop, 1669091SN/A pkt->getAddr()); 1675197SN/A 1689712SN/A // store size and command as they might be modified when 1699712SN/A // forwarding the packet 1709712SN/A unsigned int pkt_size = pkt->hasData() ? pkt->getSize() : 0; 1719712SN/A unsigned int pkt_cmd = pkt->cmdToIndex(); 1729712SN/A 17310719SMarco.Balboni@ARM.com // store the old header delay so we can restore it if needed 17410719SMarco.Balboni@ARM.com Tick old_header_delay = pkt->headerDelay; 17510719SMarco.Balboni@ARM.com 17610719SMarco.Balboni@ARM.com // a request sees the frontend and forward latency 17710719SMarco.Balboni@ARM.com Tick xbar_delay = (frontendLatency + forwardLatency) * clockPeriod(); 17810719SMarco.Balboni@ARM.com 17910719SMarco.Balboni@ARM.com // set the packet header and payload delay 18010719SMarco.Balboni@ARM.com calcPacketTiming(pkt, xbar_delay); 18110719SMarco.Balboni@ARM.com 18210719SMarco.Balboni@ARM.com // determine how long to be crossbar layer is busy 18310719SMarco.Balboni@ARM.com Tick packetFinishTime = clockEdge(Cycles(1)) + pkt->payloadDelay; 1844912SN/A 18510821Sandreas.hansson@arm.com if (!system->bypassCaches()) { 18611127Sandreas.hansson@arm.com assert(pkt->snoopDelay == 0); 18711127Sandreas.hansson@arm.com 1888979SN/A // the packet is a memory-mapped request and should be 1898979SN/A // broadcasted to our snoopers but the source 19010402SN/A if (snoopFilter) { 19110402SN/A // check with the snoop filter where to forward this packet 19210402SN/A auto sf_res = snoopFilter->lookupRequest(pkt, *src_port); 19311126Sandreas.hansson@arm.com // the time required by a packet to be delivered through 19411126Sandreas.hansson@arm.com // the xbar has to be charged also with to lookup latency 19511126Sandreas.hansson@arm.com // of the snoop filter 19610719SMarco.Balboni@ARM.com pkt->headerDelay += sf_res.second * clockPeriod(); 19710405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingReq: src %s %s 0x%x"\ 19810402SN/A " SF size: %i lat: %i\n", src_port->name(), 19910402SN/A pkt->cmdString(), pkt->getAddr(), sf_res.first.size(), 20010402SN/A sf_res.second); 20110402SN/A forwardTiming(pkt, slave_port_id, sf_res.first); 20210402SN/A } else { 20310402SN/A forwardTiming(pkt, slave_port_id); 20410402SN/A } 20511127Sandreas.hansson@arm.com 20611127Sandreas.hansson@arm.com // add the snoop delay to our header delay, and then reset it 20711127Sandreas.hansson@arm.com pkt->headerDelay += pkt->snoopDelay; 20811127Sandreas.hansson@arm.com pkt->snoopDelay = 0; 2098979SN/A } 2108948SN/A 21110883Sali.jafri@arm.com // forwardTiming snooped into peer caches of the sender, and if 21210883Sali.jafri@arm.com // this is a clean evict, but the packet is found in a cache, do 21310883Sali.jafri@arm.com // not forward it 21410883Sali.jafri@arm.com if (pkt->cmd == MemCmd::CleanEvict && pkt->isBlockCached()) { 21510883Sali.jafri@arm.com DPRINTF(CoherentXBar, "recvTimingReq: Clean evict 0x%x still cached, " 21610883Sali.jafri@arm.com "not forwarding\n", pkt->getAddr()); 21710883Sali.jafri@arm.com 21810883Sali.jafri@arm.com // update the layer state and schedule an idle event 21910883Sali.jafri@arm.com reqLayers[master_port_id]->succeededTiming(packetFinishTime); 22011190Sandreas.hansson@arm.com 22111190Sandreas.hansson@arm.com // queue the packet for deletion 22211190Sandreas.hansson@arm.com pendingDelete.reset(pkt); 22311190Sandreas.hansson@arm.com 22410883Sali.jafri@arm.com return true; 22510883Sali.jafri@arm.com } 22610883Sali.jafri@arm.com 22710656Sandreas.hansson@arm.com // remember if the packet will generate a snoop response 22810656Sandreas.hansson@arm.com const bool expect_snoop_resp = !is_inhibited && pkt->memInhibitAsserted(); 22910656Sandreas.hansson@arm.com const bool expect_response = pkt->needsResponse() && 23010656Sandreas.hansson@arm.com !pkt->memInhibitAsserted(); 2318915SN/A 2329612SN/A // since it is a normal request, attempt to send the packet 2339712SN/A bool success = masterPorts[master_port_id]->sendTimingReq(pkt); 2348948SN/A 23510821Sandreas.hansson@arm.com if (snoopFilter && !system->bypassCaches()) { 23610402SN/A // Let the snoop filter know about the success of the send operation 23711131Sandreas.hansson@arm.com snoopFilter->finishRequest(!success, pkt); 23810402SN/A } 23910402SN/A 24010656Sandreas.hansson@arm.com // check if we were successful in sending the packet onwards 24110656Sandreas.hansson@arm.com if (!success) { 24210656Sandreas.hansson@arm.com // express snoops and inhibited packets should never be forced 24310656Sandreas.hansson@arm.com // to retry 24410656Sandreas.hansson@arm.com assert(!is_express_snoop); 24510656Sandreas.hansson@arm.com assert(!pkt->memInhibitAsserted()); 24610656Sandreas.hansson@arm.com 24710719SMarco.Balboni@ARM.com // restore the header delay 24810719SMarco.Balboni@ARM.com pkt->headerDelay = old_header_delay; 24910656Sandreas.hansson@arm.com 25010656Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingReq: src %s %s 0x%x RETRY\n", 25110656Sandreas.hansson@arm.com src_port->name(), pkt->cmdString(), pkt->getAddr()); 25210656Sandreas.hansson@arm.com 25310656Sandreas.hansson@arm.com // update the layer state and schedule an idle event 25410656Sandreas.hansson@arm.com reqLayers[master_port_id]->failedTiming(src_port, 25510719SMarco.Balboni@ARM.com clockEdge(Cycles(1))); 2569091SN/A } else { 25710656Sandreas.hansson@arm.com // express snoops currently bypass the crossbar state entirely 25810656Sandreas.hansson@arm.com if (!is_express_snoop) { 25910656Sandreas.hansson@arm.com // if this particular request will generate a snoop 26010656Sandreas.hansson@arm.com // response 26110656Sandreas.hansson@arm.com if (expect_snoop_resp) { 26210656Sandreas.hansson@arm.com // we should never have an exsiting request outstanding 26310656Sandreas.hansson@arm.com assert(outstandingSnoop.find(pkt->req) == 26410656Sandreas.hansson@arm.com outstandingSnoop.end()); 26510656Sandreas.hansson@arm.com outstandingSnoop.insert(pkt->req); 2668948SN/A 26710656Sandreas.hansson@arm.com // basic sanity check on the outstanding snoops 26810656Sandreas.hansson@arm.com panic_if(outstandingSnoop.size() > 512, 26910656Sandreas.hansson@arm.com "Outstanding snoop requests exceeded 512\n"); 27010656Sandreas.hansson@arm.com } 2718948SN/A 27210656Sandreas.hansson@arm.com // remember where to route the normal response to 27310656Sandreas.hansson@arm.com if (expect_response || expect_snoop_resp) { 27410656Sandreas.hansson@arm.com assert(routeTo.find(pkt->req) == routeTo.end()); 27510656Sandreas.hansson@arm.com routeTo[pkt->req] = slave_port_id; 2769549SN/A 27710656Sandreas.hansson@arm.com panic_if(routeTo.size() > 512, 27810656Sandreas.hansson@arm.com "Routing table exceeds 512 packets\n"); 27910656Sandreas.hansson@arm.com } 2808948SN/A 28110405Sandreas.hansson@arm.com // update the layer state and schedule an idle event 2829715SN/A reqLayers[master_port_id]->succeededTiming(packetFinishTime); 2839091SN/A } 2848975SN/A 28510656Sandreas.hansson@arm.com // stats updates only consider packets that were successfully sent 2869712SN/A pktCount[slave_port_id][master_port_id]++; 28710405Sandreas.hansson@arm.com pktSize[slave_port_id][master_port_id] += pkt_size; 2889712SN/A transDist[pkt_cmd]++; 28910656Sandreas.hansson@arm.com 29010656Sandreas.hansson@arm.com if (is_express_snoop) 29110656Sandreas.hansson@arm.com snoops++; 2929712SN/A } 2939712SN/A 2949091SN/A return success; 2958975SN/A} 2968975SN/A 2978975SN/Abool 29810405Sandreas.hansson@arm.comCoherentXBar::recvTimingResp(PacketPtr pkt, PortID master_port_id) 2998975SN/A{ 3008975SN/A // determine the source port based on the id 3019032SN/A MasterPort *src_port = masterPorts[master_port_id]; 3028975SN/A 30310656Sandreas.hansson@arm.com // determine the destination 30410656Sandreas.hansson@arm.com const auto route_lookup = routeTo.find(pkt->req); 30510656Sandreas.hansson@arm.com assert(route_lookup != routeTo.end()); 30610656Sandreas.hansson@arm.com const PortID slave_port_id = route_lookup->second; 30710572Sandreas.hansson@arm.com assert(slave_port_id != InvalidPortID); 30810572Sandreas.hansson@arm.com assert(slave_port_id < respLayers.size()); 3099713SN/A 31010405Sandreas.hansson@arm.com // test if the crossbar should be considered occupied for the 31110405Sandreas.hansson@arm.com // current port 3129715SN/A if (!respLayers[slave_port_id]->tryTiming(src_port)) { 31310405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingResp: src %s %s 0x%x BUSY\n", 3148975SN/A src_port->name(), pkt->cmdString(), pkt->getAddr()); 3158975SN/A return false; 3168975SN/A } 3178975SN/A 31810405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingResp: src %s %s 0x%x\n", 3198975SN/A src_port->name(), pkt->cmdString(), pkt->getAddr()); 3208975SN/A 3219712SN/A // store size and command as they might be modified when 3229712SN/A // forwarding the packet 3239712SN/A unsigned int pkt_size = pkt->hasData() ? pkt->getSize() : 0; 3249712SN/A unsigned int pkt_cmd = pkt->cmdToIndex(); 3259712SN/A 32610719SMarco.Balboni@ARM.com // a response sees the response latency 32710719SMarco.Balboni@ARM.com Tick xbar_delay = responseLatency * clockPeriod(); 32810719SMarco.Balboni@ARM.com 32910719SMarco.Balboni@ARM.com // set the packet header and payload delay 33010719SMarco.Balboni@ARM.com calcPacketTiming(pkt, xbar_delay); 33110719SMarco.Balboni@ARM.com 33210719SMarco.Balboni@ARM.com // determine how long to be crossbar layer is busy 33310719SMarco.Balboni@ARM.com Tick packetFinishTime = clockEdge(Cycles(1)) + pkt->payloadDelay; 3348975SN/A 33510821Sandreas.hansson@arm.com if (snoopFilter && !system->bypassCaches()) { 33610402SN/A // let the snoop filter inspect the response and update its state 33710402SN/A snoopFilter->updateResponse(pkt, *slavePorts[slave_port_id]); 33810402SN/A } 33910402SN/A 34010888Sandreas.hansson@arm.com // send the packet through the destination slave port and pay for 34110888Sandreas.hansson@arm.com // any outstanding header delay 34210888Sandreas.hansson@arm.com Tick latency = pkt->headerDelay; 34310888Sandreas.hansson@arm.com pkt->headerDelay = 0; 34410888Sandreas.hansson@arm.com slavePorts[slave_port_id]->schedTimingResp(pkt, curTick() + latency); 3458975SN/A 34610656Sandreas.hansson@arm.com // remove the request from the routing table 34710656Sandreas.hansson@arm.com routeTo.erase(route_lookup); 34810656Sandreas.hansson@arm.com 3499715SN/A respLayers[slave_port_id]->succeededTiming(packetFinishTime); 3508975SN/A 3519712SN/A // stats updates 3529712SN/A pktCount[slave_port_id][master_port_id]++; 35310405Sandreas.hansson@arm.com pktSize[slave_port_id][master_port_id] += pkt_size; 3549712SN/A transDist[pkt_cmd]++; 3559712SN/A 3568975SN/A return true; 3578975SN/A} 3588975SN/A 3598975SN/Avoid 36010405Sandreas.hansson@arm.comCoherentXBar::recvTimingSnoopReq(PacketPtr pkt, PortID master_port_id) 3618975SN/A{ 36210405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopReq: src %s %s 0x%x\n", 3639032SN/A masterPorts[master_port_id]->name(), pkt->cmdString(), 3648975SN/A pkt->getAddr()); 3658975SN/A 3669712SN/A // update stats here as we know the forwarding will succeed 3679712SN/A transDist[pkt->cmdToIndex()]++; 36810405Sandreas.hansson@arm.com snoops++; 3699712SN/A 3708975SN/A // we should only see express snoops from caches 3718975SN/A assert(pkt->isExpressSnoop()); 3728975SN/A 37311127Sandreas.hansson@arm.com // set the packet header and payload delay, for now use forward latency 37411127Sandreas.hansson@arm.com // @todo Assess the choice of latency further 37511127Sandreas.hansson@arm.com calcPacketTiming(pkt, forwardLatency * clockPeriod()); 37611127Sandreas.hansson@arm.com 37710656Sandreas.hansson@arm.com // remeber if the packet is inhibited so we can see if it changes 37810656Sandreas.hansson@arm.com const bool is_inhibited = pkt->memInhibitAsserted(); 3799032SN/A 38011127Sandreas.hansson@arm.com assert(pkt->snoopDelay == 0); 38111127Sandreas.hansson@arm.com 38210402SN/A if (snoopFilter) { 38310402SN/A // let the Snoop Filter work its magic and guide probing 38410402SN/A auto sf_res = snoopFilter->lookupSnoop(pkt); 38511126Sandreas.hansson@arm.com // the time required by a packet to be delivered through 38611126Sandreas.hansson@arm.com // the xbar has to be charged also with to lookup latency 38711126Sandreas.hansson@arm.com // of the snoop filter 38811126Sandreas.hansson@arm.com pkt->headerDelay += sf_res.second * clockPeriod(); 38910405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopReq: src %s %s 0x%x"\ 39010402SN/A " SF size: %i lat: %i\n", masterPorts[master_port_id]->name(), 39110402SN/A pkt->cmdString(), pkt->getAddr(), sf_res.first.size(), 39210402SN/A sf_res.second); 39310402SN/A 39410402SN/A // forward to all snoopers 39510402SN/A forwardTiming(pkt, InvalidPortID, sf_res.first); 39610402SN/A } else { 39710402SN/A forwardTiming(pkt, InvalidPortID); 39810402SN/A } 3998975SN/A 40011127Sandreas.hansson@arm.com // add the snoop delay to our header delay, and then reset it 40111127Sandreas.hansson@arm.com pkt->headerDelay += pkt->snoopDelay; 40211127Sandreas.hansson@arm.com pkt->snoopDelay = 0; 40311127Sandreas.hansson@arm.com 40410656Sandreas.hansson@arm.com // if we can expect a response, remember how to route it 40510656Sandreas.hansson@arm.com if (!is_inhibited && pkt->memInhibitAsserted()) { 40610656Sandreas.hansson@arm.com assert(routeTo.find(pkt->req) == routeTo.end()); 40710656Sandreas.hansson@arm.com routeTo[pkt->req] = master_port_id; 40810656Sandreas.hansson@arm.com } 40910656Sandreas.hansson@arm.com 4108975SN/A // a snoop request came from a connected slave device (one of 4118975SN/A // our master ports), and if it is not coming from the slave 4128975SN/A // device responsible for the address range something is 4138975SN/A // wrong, hence there is nothing further to do as the packet 4148975SN/A // would be going back to where it came from 4159032SN/A assert(master_port_id == findPort(pkt->getAddr())); 4168975SN/A} 4178975SN/A 4188975SN/Abool 41910405Sandreas.hansson@arm.comCoherentXBar::recvTimingSnoopResp(PacketPtr pkt, PortID slave_port_id) 4208975SN/A{ 4218975SN/A // determine the source port based on the id 4229032SN/A SlavePort* src_port = slavePorts[slave_port_id]; 4238975SN/A 42410656Sandreas.hansson@arm.com // get the destination 42510656Sandreas.hansson@arm.com const auto route_lookup = routeTo.find(pkt->req); 42610656Sandreas.hansson@arm.com assert(route_lookup != routeTo.end()); 42710656Sandreas.hansson@arm.com const PortID dest_port_id = route_lookup->second; 42810572Sandreas.hansson@arm.com assert(dest_port_id != InvalidPortID); 4299714SN/A 4309714SN/A // determine if the response is from a snoop request we 4319714SN/A // created as the result of a normal request (in which case it 43210656Sandreas.hansson@arm.com // should be in the outstandingSnoop), or if we merely forwarded 4339714SN/A // someone else's snoop request 43410656Sandreas.hansson@arm.com const bool forwardAsSnoop = outstandingSnoop.find(pkt->req) == 43510656Sandreas.hansson@arm.com outstandingSnoop.end(); 4369714SN/A 43710405Sandreas.hansson@arm.com // test if the crossbar should be considered occupied for the 43810405Sandreas.hansson@arm.com // current port, note that the check is bypassed if the response 43910405Sandreas.hansson@arm.com // is being passed on as a normal response since this is occupying 44010405Sandreas.hansson@arm.com // the response layer rather than the snoop response layer 4419715SN/A if (forwardAsSnoop) { 44210572Sandreas.hansson@arm.com assert(dest_port_id < snoopLayers.size()); 4439715SN/A if (!snoopLayers[dest_port_id]->tryTiming(src_port)) { 44410405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopResp: src %s %s 0x%x BUSY\n", 4459715SN/A src_port->name(), pkt->cmdString(), pkt->getAddr()); 4469715SN/A return false; 4479715SN/A } 4489716SN/A } else { 4499716SN/A // get the master port that mirrors this slave port internally 4509716SN/A MasterPort* snoop_port = snoopRespPorts[slave_port_id]; 45110572Sandreas.hansson@arm.com assert(dest_port_id < respLayers.size()); 4529716SN/A if (!respLayers[dest_port_id]->tryTiming(snoop_port)) { 45310405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopResp: src %s %s 0x%x BUSY\n", 4549716SN/A snoop_port->name(), pkt->cmdString(), pkt->getAddr()); 4559716SN/A return false; 4569716SN/A } 4578975SN/A } 4588975SN/A 45910405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopResp: src %s %s 0x%x\n", 4608975SN/A src_port->name(), pkt->cmdString(), pkt->getAddr()); 4618975SN/A 4629712SN/A // store size and command as they might be modified when 4639712SN/A // forwarding the packet 4649712SN/A unsigned int pkt_size = pkt->hasData() ? pkt->getSize() : 0; 4659712SN/A unsigned int pkt_cmd = pkt->cmdToIndex(); 4669712SN/A 4678975SN/A // responses are never express snoops 4688975SN/A assert(!pkt->isExpressSnoop()); 4698975SN/A 47010719SMarco.Balboni@ARM.com // a snoop response sees the snoop response latency, and if it is 47110719SMarco.Balboni@ARM.com // forwarded as a normal response, the response latency 47210719SMarco.Balboni@ARM.com Tick xbar_delay = 47310719SMarco.Balboni@ARM.com (forwardAsSnoop ? snoopResponseLatency : responseLatency) * 47410719SMarco.Balboni@ARM.com clockPeriod(); 47510719SMarco.Balboni@ARM.com 47610719SMarco.Balboni@ARM.com // set the packet header and payload delay 47710719SMarco.Balboni@ARM.com calcPacketTiming(pkt, xbar_delay); 47810719SMarco.Balboni@ARM.com 47910719SMarco.Balboni@ARM.com // determine how long to be crossbar layer is busy 48010719SMarco.Balboni@ARM.com Tick packetFinishTime = clockEdge(Cycles(1)) + pkt->payloadDelay; 4818975SN/A 4829714SN/A // forward it either as a snoop response or a normal response 4839714SN/A if (forwardAsSnoop) { 4849714SN/A // this is a snoop response to a snoop request we forwarded, 4859714SN/A // e.g. coming from the L1 and going to the L2, and it should 4869714SN/A // be forwarded as a snoop response 48710402SN/A 48810402SN/A if (snoopFilter) { 48910402SN/A // update the probe filter so that it can properly track the line 49010402SN/A snoopFilter->updateSnoopForward(pkt, *slavePorts[slave_port_id], 49110402SN/A *masterPorts[dest_port_id]); 49210402SN/A } 49310402SN/A 4949712SN/A bool success M5_VAR_USED = 4959712SN/A masterPorts[dest_port_id]->sendTimingSnoopResp(pkt); 4969712SN/A pktCount[slave_port_id][dest_port_id]++; 49710405Sandreas.hansson@arm.com pktSize[slave_port_id][dest_port_id] += pkt_size; 4988975SN/A assert(success); 4999714SN/A 5009715SN/A snoopLayers[dest_port_id]->succeededTiming(packetFinishTime); 5013244SN/A } else { 5028975SN/A // we got a snoop response on one of our slave ports, 50310405Sandreas.hansson@arm.com // i.e. from a coherent master connected to the crossbar, and 50410405Sandreas.hansson@arm.com // since we created the snoop request as part of recvTiming, 50510405Sandreas.hansson@arm.com // this should now be a normal response again 50610656Sandreas.hansson@arm.com outstandingSnoop.erase(pkt->req); 5078948SN/A 50810656Sandreas.hansson@arm.com // this is a snoop response from a coherent master, hence it 50910656Sandreas.hansson@arm.com // should never go back to where the snoop response came from, 51010656Sandreas.hansson@arm.com // but instead to where the original request came from 5119712SN/A assert(slave_port_id != dest_port_id); 5128948SN/A 51310402SN/A if (snoopFilter) { 51410402SN/A // update the probe filter so that it can properly track the line 51510402SN/A snoopFilter->updateSnoopResponse(pkt, *slavePorts[slave_port_id], 51610402SN/A *slavePorts[dest_port_id]); 51710402SN/A } 51810402SN/A 51910405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopResp: src %s %s 0x%x"\ 52010402SN/A " FWD RESP\n", src_port->name(), pkt->cmdString(), 52110402SN/A pkt->getAddr()); 52210402SN/A 5239714SN/A // as a normal response, it should go back to a master through 52410888Sandreas.hansson@arm.com // one of our slave ports, we also pay for any outstanding 52510888Sandreas.hansson@arm.com // header latency 52610888Sandreas.hansson@arm.com Tick latency = pkt->headerDelay; 52710888Sandreas.hansson@arm.com pkt->headerDelay = 0; 52810888Sandreas.hansson@arm.com slavePorts[dest_port_id]->schedTimingResp(pkt, curTick() + latency); 5299716SN/A 5309716SN/A respLayers[dest_port_id]->succeededTiming(packetFinishTime); 5313244SN/A } 5323244SN/A 53310656Sandreas.hansson@arm.com // remove the request from the routing table 53410656Sandreas.hansson@arm.com routeTo.erase(route_lookup); 53510656Sandreas.hansson@arm.com 5369712SN/A // stats updates 5379712SN/A transDist[pkt_cmd]++; 53810405Sandreas.hansson@arm.com snoops++; 5399712SN/A 5408948SN/A return true; 5418948SN/A} 5428948SN/A 5433210SN/A 5448948SN/Avoid 54510405Sandreas.hansson@arm.comCoherentXBar::forwardTiming(PacketPtr pkt, PortID exclude_slave_port_id, 54610888Sandreas.hansson@arm.com const std::vector<QueuedSlavePort*>& dests) 5478948SN/A{ 54810405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "%s for %s address %x size %d\n", __func__, 5499663SN/A pkt->cmdString(), pkt->getAddr(), pkt->getSize()); 5509663SN/A 5519524SN/A // snoops should only happen if the system isn't bypassing caches 5529524SN/A assert(!system->bypassCaches()); 5539524SN/A 55410401SN/A unsigned fanout = 0; 55510401SN/A 55610405Sandreas.hansson@arm.com for (const auto& p: dests) { 5578948SN/A // we could have gotten this request from a snooping master 5588948SN/A // (corresponding to our own slave port that is also in 5598948SN/A // snoopPorts) and should not send it back to where it came 5608948SN/A // from 5619031SN/A if (exclude_slave_port_id == InvalidPortID || 5628948SN/A p->getId() != exclude_slave_port_id) { 5638948SN/A // cache is not allowed to refuse snoop 5648975SN/A p->sendTimingSnoopReq(pkt); 56510401SN/A fanout++; 5668948SN/A } 5678948SN/A } 56810401SN/A 56910401SN/A // Stats for fanout of this forward operation 57010401SN/A snoopFanout.sample(fanout); 5712497SN/A} 5722497SN/A 5739092SN/Avoid 57410713Sandreas.hansson@arm.comCoherentXBar::recvReqRetry(PortID master_port_id) 5759092SN/A{ 5769093SN/A // responses and snoop responses never block on forwarding them, 5779093SN/A // so the retry will always be coming from a port to which we 5789093SN/A // tried to forward a request 5799715SN/A reqLayers[master_port_id]->recvRetry(); 5809092SN/A} 5819092SN/A 5829036SN/ATick 58310405Sandreas.hansson@arm.comCoherentXBar::recvAtomic(PacketPtr pkt, PortID slave_port_id) 5842657SN/A{ 58510405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvAtomic: packet src %s addr 0x%x cmd %s\n", 5869032SN/A slavePorts[slave_port_id]->name(), pkt->getAddr(), 5878949SN/A pkt->cmdString()); 5888915SN/A 58910405Sandreas.hansson@arm.com unsigned int pkt_size = pkt->hasData() ? pkt->getSize() : 0; 59010405Sandreas.hansson@arm.com unsigned int pkt_cmd = pkt->cmdToIndex(); 5919712SN/A 5928979SN/A MemCmd snoop_response_cmd = MemCmd::InvalidCmd; 5938979SN/A Tick snoop_response_latency = 0; 5948979SN/A 59510821Sandreas.hansson@arm.com if (!system->bypassCaches()) { 5968979SN/A // forward to all snoopers but the source 59710402SN/A std::pair<MemCmd, Tick> snoop_result; 59810402SN/A if (snoopFilter) { 59910402SN/A // check with the snoop filter where to forward this packet 60010402SN/A auto sf_res = 60110402SN/A snoopFilter->lookupRequest(pkt, *slavePorts[slave_port_id]); 60210402SN/A snoop_response_latency += sf_res.second * clockPeriod(); 60310405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "%s: src %s %s 0x%x"\ 60410402SN/A " SF size: %i lat: %i\n", __func__, 60510402SN/A slavePorts[slave_port_id]->name(), pkt->cmdString(), 60610402SN/A pkt->getAddr(), sf_res.first.size(), sf_res.second); 60711130Sali.jafri@arm.com 60811130Sali.jafri@arm.com // let the snoop filter know about the success of the send 60911130Sali.jafri@arm.com // operation, and do it even before sending it onwards to 61011130Sali.jafri@arm.com // avoid situations where atomic upward snoops sneak in 61111130Sali.jafri@arm.com // between and change the filter state 61211131Sandreas.hansson@arm.com snoopFilter->finishRequest(false, pkt); 61311130Sali.jafri@arm.com 61410402SN/A snoop_result = forwardAtomic(pkt, slave_port_id, InvalidPortID, 61510402SN/A sf_res.first); 61610402SN/A } else { 61710402SN/A snoop_result = forwardAtomic(pkt, slave_port_id); 61810402SN/A } 6198979SN/A snoop_response_cmd = snoop_result.first; 62010402SN/A snoop_response_latency += snoop_result.second; 6218979SN/A } 6228915SN/A 62311130Sali.jafri@arm.com // forwardAtomic snooped into peer caches of the sender, and if 62411130Sali.jafri@arm.com // this is a clean evict, but the packet is found in a cache, do 62511130Sali.jafri@arm.com // not forward it 62611130Sali.jafri@arm.com if (pkt->cmd == MemCmd::CleanEvict && pkt->isBlockCached()) { 62711130Sali.jafri@arm.com DPRINTF(CoherentXBar, "recvAtomic: Clean evict 0x%x still cached, " 62811130Sali.jafri@arm.com "not forwarding\n", pkt->getAddr()); 62911130Sali.jafri@arm.com return 0; 63011130Sali.jafri@arm.com } 63111130Sali.jafri@arm.com 6328948SN/A // even if we had a snoop response, we must continue and also 6338948SN/A // perform the actual request at the destination 63410405Sandreas.hansson@arm.com PortID master_port_id = findPort(pkt->getAddr()); 63510405Sandreas.hansson@arm.com 63610405Sandreas.hansson@arm.com // stats updates for the request 63710405Sandreas.hansson@arm.com pktCount[slave_port_id][master_port_id]++; 63810405Sandreas.hansson@arm.com pktSize[slave_port_id][master_port_id] += pkt_size; 63910405Sandreas.hansson@arm.com transDist[pkt_cmd]++; 6408948SN/A 6418948SN/A // forward the request to the appropriate destination 64210405Sandreas.hansson@arm.com Tick response_latency = masterPorts[master_port_id]->sendAtomic(pkt); 6438948SN/A 64411130Sali.jafri@arm.com // if lower levels have replied, tell the snoop filter 64511130Sali.jafri@arm.com if (!system->bypassCaches() && snoopFilter && pkt->isResponse()) { 64610402SN/A snoopFilter->updateResponse(pkt, *slavePorts[slave_port_id]); 64710402SN/A } 64810402SN/A 6498948SN/A // if we got a response from a snooper, restore it here 6508948SN/A if (snoop_response_cmd != MemCmd::InvalidCmd) { 6518948SN/A // no one else should have responded 6528948SN/A assert(!pkt->isResponse()); 6538948SN/A pkt->cmd = snoop_response_cmd; 6548948SN/A response_latency = snoop_response_latency; 6558948SN/A } 6568948SN/A 6579712SN/A // add the response data 65810405Sandreas.hansson@arm.com if (pkt->isResponse()) { 65910405Sandreas.hansson@arm.com pkt_size = pkt->hasData() ? pkt->getSize() : 0; 66010405Sandreas.hansson@arm.com pkt_cmd = pkt->cmdToIndex(); 66110405Sandreas.hansson@arm.com 66210405Sandreas.hansson@arm.com // stats updates 66310405Sandreas.hansson@arm.com pktCount[slave_port_id][master_port_id]++; 66410405Sandreas.hansson@arm.com pktSize[slave_port_id][master_port_id] += pkt_size; 66510405Sandreas.hansson@arm.com transDist[pkt_cmd]++; 66610405Sandreas.hansson@arm.com } 6679712SN/A 66810694SMarco.Balboni@ARM.com // @todo: Not setting header time 66910694SMarco.Balboni@ARM.com pkt->payloadDelay = response_latency; 6708948SN/A return response_latency; 6718948SN/A} 6728948SN/A 6738948SN/ATick 67410405Sandreas.hansson@arm.comCoherentXBar::recvAtomicSnoop(PacketPtr pkt, PortID master_port_id) 6758948SN/A{ 67610405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvAtomicSnoop: packet src %s addr 0x%x cmd %s\n", 6779032SN/A masterPorts[master_port_id]->name(), pkt->getAddr(), 6788949SN/A pkt->cmdString()); 6798948SN/A 6809712SN/A // add the request snoop data 68110405Sandreas.hansson@arm.com snoops++; 6829712SN/A 6838948SN/A // forward to all snoopers 68410402SN/A std::pair<MemCmd, Tick> snoop_result; 68510402SN/A Tick snoop_response_latency = 0; 68610402SN/A if (snoopFilter) { 68710402SN/A auto sf_res = snoopFilter->lookupSnoop(pkt); 68810402SN/A snoop_response_latency += sf_res.second * clockPeriod(); 68910405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "%s: src %s %s 0x%x SF size: %i lat: %i\n", 69010402SN/A __func__, masterPorts[master_port_id]->name(), pkt->cmdString(), 69110402SN/A pkt->getAddr(), sf_res.first.size(), sf_res.second); 69210402SN/A snoop_result = forwardAtomic(pkt, InvalidPortID, master_port_id, 69310402SN/A sf_res.first); 69410402SN/A } else { 69510402SN/A snoop_result = forwardAtomic(pkt, InvalidPortID); 69610402SN/A } 6978948SN/A MemCmd snoop_response_cmd = snoop_result.first; 69810402SN/A snoop_response_latency += snoop_result.second; 6998948SN/A 7008948SN/A if (snoop_response_cmd != MemCmd::InvalidCmd) 7018948SN/A pkt->cmd = snoop_response_cmd; 7028948SN/A 7039712SN/A // add the response snoop data 70410401SN/A if (pkt->isResponse()) { 70510405Sandreas.hansson@arm.com snoops++; 70610401SN/A } 7079712SN/A 70810694SMarco.Balboni@ARM.com // @todo: Not setting header time 70910694SMarco.Balboni@ARM.com pkt->payloadDelay = snoop_response_latency; 7108948SN/A return snoop_response_latency; 7118948SN/A} 7128948SN/A 7138948SN/Astd::pair<MemCmd, Tick> 71410405Sandreas.hansson@arm.comCoherentXBar::forwardAtomic(PacketPtr pkt, PortID exclude_slave_port_id, 71510402SN/A PortID source_master_port_id, 71610888Sandreas.hansson@arm.com const std::vector<QueuedSlavePort*>& dests) 7178948SN/A{ 7189032SN/A // the packet may be changed on snoops, record the original 7199032SN/A // command to enable us to restore it between snoops so that 7208948SN/A // additional snoops can take place properly 7214626SN/A MemCmd orig_cmd = pkt->cmd; 7224879SN/A MemCmd snoop_response_cmd = MemCmd::InvalidCmd; 7234879SN/A Tick snoop_response_latency = 0; 7243662SN/A 7259524SN/A // snoops should only happen if the system isn't bypassing caches 7269524SN/A assert(!system->bypassCaches()); 7279524SN/A 72810401SN/A unsigned fanout = 0; 72910401SN/A 73010405Sandreas.hansson@arm.com for (const auto& p: dests) { 7318915SN/A // we could have gotten this request from a snooping master 7328915SN/A // (corresponding to our own slave port that is also in 7338915SN/A // snoopPorts) and should not send it back to where it came 7348915SN/A // from 73510402SN/A if (exclude_slave_port_id != InvalidPortID && 73610402SN/A p->getId() == exclude_slave_port_id) 73710402SN/A continue; 73810401SN/A 73910402SN/A Tick latency = p->sendAtomicSnoop(pkt); 74010402SN/A fanout++; 74110402SN/A 74210402SN/A // in contrast to a functional access, we have to keep on 74310402SN/A // going as all snoopers must be updated even if we get a 74410402SN/A // response 74510402SN/A if (!pkt->isResponse()) 74610402SN/A continue; 74710402SN/A 74810402SN/A // response from snoop agent 74910402SN/A assert(pkt->cmd != orig_cmd); 75010402SN/A assert(pkt->memInhibitAsserted()); 75110402SN/A // should only happen once 75210402SN/A assert(snoop_response_cmd == MemCmd::InvalidCmd); 75310402SN/A // save response state 75410402SN/A snoop_response_cmd = pkt->cmd; 75510402SN/A snoop_response_latency = latency; 75610402SN/A 75710402SN/A if (snoopFilter) { 75810402SN/A // Handle responses by the snoopers and differentiate between 75910402SN/A // responses to requests from above and snoops from below 76010402SN/A if (source_master_port_id != InvalidPortID) { 76110402SN/A // Getting a response for a snoop from below 76210402SN/A assert(exclude_slave_port_id == InvalidPortID); 76310402SN/A snoopFilter->updateSnoopForward(pkt, *p, 76410402SN/A *masterPorts[source_master_port_id]); 76510402SN/A } else { 76610402SN/A // Getting a response for a request from above 76710402SN/A assert(source_master_port_id == InvalidPortID); 76810402SN/A snoopFilter->updateSnoopResponse(pkt, *p, 76910402SN/A *slavePorts[exclude_slave_port_id]); 7704626SN/A } 7714626SN/A } 77210402SN/A // restore original packet state for remaining snoopers 77310402SN/A pkt->cmd = orig_cmd; 7744626SN/A } 7754626SN/A 77610401SN/A // Stats for fanout 77710401SN/A snoopFanout.sample(fanout); 77810401SN/A 7798948SN/A // the packet is restored as part of the loop and any potential 7808948SN/A // snoop response is part of the returned pair 7818948SN/A return std::make_pair(snoop_response_cmd, snoop_response_latency); 7822497SN/A} 7832497SN/A 7842497SN/Avoid 78510405Sandreas.hansson@arm.comCoherentXBar::recvFunctional(PacketPtr pkt, PortID slave_port_id) 7862497SN/A{ 7878663SN/A if (!pkt->isPrint()) { 7888663SN/A // don't do DPRINTFs on PrintReq as it clutters up the output 78910405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, 7908949SN/A "recvFunctional: packet src %s addr 0x%x cmd %s\n", 7919032SN/A slavePorts[slave_port_id]->name(), pkt->getAddr(), 7928663SN/A pkt->cmdString()); 7938663SN/A } 7948663SN/A 79510821Sandreas.hansson@arm.com if (!system->bypassCaches()) { 7968979SN/A // forward to all snoopers but the source 7979032SN/A forwardFunctional(pkt, slave_port_id); 7988979SN/A } 7994912SN/A 8008948SN/A // there is no need to continue if the snooping has found what we 8018948SN/A // were looking for and the packet is already a response 8028948SN/A if (!pkt->isResponse()) { 80310888Sandreas.hansson@arm.com // since our slave ports are queued ports we need to check them as well 80410888Sandreas.hansson@arm.com for (const auto& p : slavePorts) { 80510888Sandreas.hansson@arm.com // if we find a response that has the data, then the 80610888Sandreas.hansson@arm.com // downstream caches/memories may be out of date, so simply stop 80710888Sandreas.hansson@arm.com // here 80810888Sandreas.hansson@arm.com if (p->checkFunctional(pkt)) { 80910888Sandreas.hansson@arm.com if (pkt->needsResponse()) 81010888Sandreas.hansson@arm.com pkt->makeResponse(); 81110888Sandreas.hansson@arm.com return; 81210888Sandreas.hansson@arm.com } 81310888Sandreas.hansson@arm.com } 81410888Sandreas.hansson@arm.com 8159031SN/A PortID dest_id = findPort(pkt->getAddr()); 8168948SN/A 8178948SN/A masterPorts[dest_id]->sendFunctional(pkt); 8188948SN/A } 8198948SN/A} 8208948SN/A 8218948SN/Avoid 82210405Sandreas.hansson@arm.comCoherentXBar::recvFunctionalSnoop(PacketPtr pkt, PortID master_port_id) 8238948SN/A{ 8248948SN/A if (!pkt->isPrint()) { 8258948SN/A // don't do DPRINTFs on PrintReq as it clutters up the output 82610405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, 8278949SN/A "recvFunctionalSnoop: packet src %s addr 0x%x cmd %s\n", 8289032SN/A masterPorts[master_port_id]->name(), pkt->getAddr(), 8298948SN/A pkt->cmdString()); 8308948SN/A } 8318948SN/A 83211188Sandreas.sandberg@arm.com for (const auto& p : slavePorts) { 83311188Sandreas.sandberg@arm.com if (p->checkFunctional(pkt)) { 83411188Sandreas.sandberg@arm.com if (pkt->needsResponse()) 83511188Sandreas.sandberg@arm.com pkt->makeResponse(); 83611188Sandreas.sandberg@arm.com return; 83711188Sandreas.sandberg@arm.com } 83811188Sandreas.sandberg@arm.com } 83911188Sandreas.sandberg@arm.com 8408948SN/A // forward to all snoopers 8419031SN/A forwardFunctional(pkt, InvalidPortID); 8428948SN/A} 8438948SN/A 8448948SN/Avoid 84510405Sandreas.hansson@arm.comCoherentXBar::forwardFunctional(PacketPtr pkt, PortID exclude_slave_port_id) 8468948SN/A{ 8479524SN/A // snoops should only happen if the system isn't bypassing caches 8489524SN/A assert(!system->bypassCaches()); 8499524SN/A 85010405Sandreas.hansson@arm.com for (const auto& p: snoopPorts) { 8518915SN/A // we could have gotten this request from a snooping master 8528915SN/A // (corresponding to our own slave port that is also in 8538915SN/A // snoopPorts) and should not send it back to where it came 8548915SN/A // from 8559031SN/A if (exclude_slave_port_id == InvalidPortID || 8568948SN/A p->getId() != exclude_slave_port_id) 8578948SN/A p->sendFunctionalSnoop(pkt); 8588915SN/A 8598948SN/A // if we get a response we are done 8608948SN/A if (pkt->isResponse()) { 8618948SN/A break; 8628915SN/A } 8633650SN/A } 8642497SN/A} 8652497SN/A 8669712SN/Avoid 86710405Sandreas.hansson@arm.comCoherentXBar::regStats() 8689712SN/A{ 86910405Sandreas.hansson@arm.com // register the stats of the base class and our layers 87010405Sandreas.hansson@arm.com BaseXBar::regStats(); 87110405Sandreas.hansson@arm.com for (auto l: reqLayers) 87210405Sandreas.hansson@arm.com l->regStats(); 87310405Sandreas.hansson@arm.com for (auto l: respLayers) 87410405Sandreas.hansson@arm.com l->regStats(); 87510405Sandreas.hansson@arm.com for (auto l: snoopLayers) 87610405Sandreas.hansson@arm.com l->regStats(); 8779712SN/A 87810405Sandreas.hansson@arm.com snoops 87910405Sandreas.hansson@arm.com .name(name() + ".snoops") 88010401SN/A .desc("Total snoops (count)") 88110401SN/A ; 88210401SN/A 88310401SN/A snoopFanout 88410401SN/A .init(0, snoopPorts.size(), 1) 88510401SN/A .name(name() + ".snoop_fanout") 88610401SN/A .desc("Request fanout histogram") 88710401SN/A ; 8889712SN/A} 8899712SN/A 89010405Sandreas.hansson@arm.comCoherentXBar * 89110405Sandreas.hansson@arm.comCoherentXBarParams::create() 8922497SN/A{ 89310405Sandreas.hansson@arm.com return new CoherentXBar(this); 8942497SN/A} 895