coherent_xbar.cc revision 11188
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{ 14310883Sali.jafri@arm.com // @todo temporary hack to deal with memory corruption issue until 14410883Sali.jafri@arm.com // 4-phase transactions are complete 14510883Sali.jafri@arm.com for (int x = 0; x < pendingDelete.size(); x++) 14610883Sali.jafri@arm.com delete pendingDelete[x]; 14710883Sali.jafri@arm.com pendingDelete.clear(); 14810883Sali.jafri@arm.com 1498975SN/A // determine the source port based on the id 1509032SN/A SlavePort *src_port = slavePorts[slave_port_id]; 1513244SN/A 1529091SN/A // remember if the packet is an express snoop 1539091SN/A bool is_express_snoop = pkt->isExpressSnoop(); 15410656Sandreas.hansson@arm.com bool is_inhibited = pkt->memInhibitAsserted(); 15510656Sandreas.hansson@arm.com // for normal requests, going downstream, the express snoop flag 15610656Sandreas.hansson@arm.com // and the inhibited flag should always be the same 15710656Sandreas.hansson@arm.com assert(is_express_snoop == is_inhibited); 1589091SN/A 1599612SN/A // determine the destination based on the address 1609712SN/A PortID master_port_id = findPort(pkt->getAddr()); 1619612SN/A 16210405Sandreas.hansson@arm.com // test if the crossbar should be considered occupied for the current 1639033SN/A // port, and exclude express snoops from the check 1649715SN/A if (!is_express_snoop && !reqLayers[master_port_id]->tryTiming(src_port)) { 16510405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingReq: src %s %s 0x%x BUSY\n", 1668949SN/A src_port->name(), pkt->cmdString(), pkt->getAddr()); 1673244SN/A return false; 1683244SN/A } 1693244SN/A 17010405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingReq: src %s %s expr %d 0x%x\n", 1719091SN/A src_port->name(), pkt->cmdString(), is_express_snoop, 1729091SN/A pkt->getAddr()); 1735197SN/A 1749712SN/A // store size and command as they might be modified when 1759712SN/A // forwarding the packet 1769712SN/A unsigned int pkt_size = pkt->hasData() ? pkt->getSize() : 0; 1779712SN/A unsigned int pkt_cmd = pkt->cmdToIndex(); 1789712SN/A 17910719SMarco.Balboni@ARM.com // store the old header delay so we can restore it if needed 18010719SMarco.Balboni@ARM.com Tick old_header_delay = pkt->headerDelay; 18110719SMarco.Balboni@ARM.com 18210719SMarco.Balboni@ARM.com // a request sees the frontend and forward latency 18310719SMarco.Balboni@ARM.com Tick xbar_delay = (frontendLatency + forwardLatency) * clockPeriod(); 18410719SMarco.Balboni@ARM.com 18510719SMarco.Balboni@ARM.com // set the packet header and payload delay 18610719SMarco.Balboni@ARM.com calcPacketTiming(pkt, xbar_delay); 18710719SMarco.Balboni@ARM.com 18810719SMarco.Balboni@ARM.com // determine how long to be crossbar layer is busy 18910719SMarco.Balboni@ARM.com Tick packetFinishTime = clockEdge(Cycles(1)) + pkt->payloadDelay; 1904912SN/A 19110821Sandreas.hansson@arm.com if (!system->bypassCaches()) { 19211127Sandreas.hansson@arm.com assert(pkt->snoopDelay == 0); 19311127Sandreas.hansson@arm.com 1948979SN/A // the packet is a memory-mapped request and should be 1958979SN/A // broadcasted to our snoopers but the source 19610402SN/A if (snoopFilter) { 19710402SN/A // check with the snoop filter where to forward this packet 19810402SN/A auto sf_res = snoopFilter->lookupRequest(pkt, *src_port); 19911126Sandreas.hansson@arm.com // the time required by a packet to be delivered through 20011126Sandreas.hansson@arm.com // the xbar has to be charged also with to lookup latency 20111126Sandreas.hansson@arm.com // of the snoop filter 20210719SMarco.Balboni@ARM.com pkt->headerDelay += sf_res.second * clockPeriod(); 20310405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingReq: src %s %s 0x%x"\ 20410402SN/A " SF size: %i lat: %i\n", src_port->name(), 20510402SN/A pkt->cmdString(), pkt->getAddr(), sf_res.first.size(), 20610402SN/A sf_res.second); 20710402SN/A forwardTiming(pkt, slave_port_id, sf_res.first); 20810402SN/A } else { 20910402SN/A forwardTiming(pkt, slave_port_id); 21010402SN/A } 21111127Sandreas.hansson@arm.com 21211127Sandreas.hansson@arm.com // add the snoop delay to our header delay, and then reset it 21311127Sandreas.hansson@arm.com pkt->headerDelay += pkt->snoopDelay; 21411127Sandreas.hansson@arm.com pkt->snoopDelay = 0; 2158979SN/A } 2168948SN/A 21710883Sali.jafri@arm.com // forwardTiming snooped into peer caches of the sender, and if 21810883Sali.jafri@arm.com // this is a clean evict, but the packet is found in a cache, do 21910883Sali.jafri@arm.com // not forward it 22010883Sali.jafri@arm.com if (pkt->cmd == MemCmd::CleanEvict && pkt->isBlockCached()) { 22110883Sali.jafri@arm.com DPRINTF(CoherentXBar, "recvTimingReq: Clean evict 0x%x still cached, " 22210883Sali.jafri@arm.com "not forwarding\n", pkt->getAddr()); 22310883Sali.jafri@arm.com 22410883Sali.jafri@arm.com // update the layer state and schedule an idle event 22510883Sali.jafri@arm.com reqLayers[master_port_id]->succeededTiming(packetFinishTime); 22610883Sali.jafri@arm.com pendingDelete.push_back(pkt); 22710883Sali.jafri@arm.com return true; 22810883Sali.jafri@arm.com } 22910883Sali.jafri@arm.com 23010656Sandreas.hansson@arm.com // remember if the packet will generate a snoop response 23110656Sandreas.hansson@arm.com const bool expect_snoop_resp = !is_inhibited && pkt->memInhibitAsserted(); 23210656Sandreas.hansson@arm.com const bool expect_response = pkt->needsResponse() && 23310656Sandreas.hansson@arm.com !pkt->memInhibitAsserted(); 2348915SN/A 2359612SN/A // since it is a normal request, attempt to send the packet 2369712SN/A bool success = masterPorts[master_port_id]->sendTimingReq(pkt); 2378948SN/A 23810821Sandreas.hansson@arm.com if (snoopFilter && !system->bypassCaches()) { 23910402SN/A // Let the snoop filter know about the success of the send operation 24011131Sandreas.hansson@arm.com snoopFilter->finishRequest(!success, pkt); 24110402SN/A } 24210402SN/A 24310656Sandreas.hansson@arm.com // check if we were successful in sending the packet onwards 24410656Sandreas.hansson@arm.com if (!success) { 24510656Sandreas.hansson@arm.com // express snoops and inhibited packets should never be forced 24610656Sandreas.hansson@arm.com // to retry 24710656Sandreas.hansson@arm.com assert(!is_express_snoop); 24810656Sandreas.hansson@arm.com assert(!pkt->memInhibitAsserted()); 24910656Sandreas.hansson@arm.com 25010719SMarco.Balboni@ARM.com // restore the header delay 25110719SMarco.Balboni@ARM.com pkt->headerDelay = old_header_delay; 25210656Sandreas.hansson@arm.com 25310656Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingReq: src %s %s 0x%x RETRY\n", 25410656Sandreas.hansson@arm.com src_port->name(), pkt->cmdString(), pkt->getAddr()); 25510656Sandreas.hansson@arm.com 25610656Sandreas.hansson@arm.com // update the layer state and schedule an idle event 25710656Sandreas.hansson@arm.com reqLayers[master_port_id]->failedTiming(src_port, 25810719SMarco.Balboni@ARM.com clockEdge(Cycles(1))); 2599091SN/A } else { 26010656Sandreas.hansson@arm.com // express snoops currently bypass the crossbar state entirely 26110656Sandreas.hansson@arm.com if (!is_express_snoop) { 26210656Sandreas.hansson@arm.com // if this particular request will generate a snoop 26310656Sandreas.hansson@arm.com // response 26410656Sandreas.hansson@arm.com if (expect_snoop_resp) { 26510656Sandreas.hansson@arm.com // we should never have an exsiting request outstanding 26610656Sandreas.hansson@arm.com assert(outstandingSnoop.find(pkt->req) == 26710656Sandreas.hansson@arm.com outstandingSnoop.end()); 26810656Sandreas.hansson@arm.com outstandingSnoop.insert(pkt->req); 2698948SN/A 27010656Sandreas.hansson@arm.com // basic sanity check on the outstanding snoops 27110656Sandreas.hansson@arm.com panic_if(outstandingSnoop.size() > 512, 27210656Sandreas.hansson@arm.com "Outstanding snoop requests exceeded 512\n"); 27310656Sandreas.hansson@arm.com } 2748948SN/A 27510656Sandreas.hansson@arm.com // remember where to route the normal response to 27610656Sandreas.hansson@arm.com if (expect_response || expect_snoop_resp) { 27710656Sandreas.hansson@arm.com assert(routeTo.find(pkt->req) == routeTo.end()); 27810656Sandreas.hansson@arm.com routeTo[pkt->req] = slave_port_id; 2799549SN/A 28010656Sandreas.hansson@arm.com panic_if(routeTo.size() > 512, 28110656Sandreas.hansson@arm.com "Routing table exceeds 512 packets\n"); 28210656Sandreas.hansson@arm.com } 2838948SN/A 28410405Sandreas.hansson@arm.com // update the layer state and schedule an idle event 2859715SN/A reqLayers[master_port_id]->succeededTiming(packetFinishTime); 2869091SN/A } 2878975SN/A 28810656Sandreas.hansson@arm.com // stats updates only consider packets that were successfully sent 2899712SN/A pktCount[slave_port_id][master_port_id]++; 29010405Sandreas.hansson@arm.com pktSize[slave_port_id][master_port_id] += pkt_size; 2919712SN/A transDist[pkt_cmd]++; 29210656Sandreas.hansson@arm.com 29310656Sandreas.hansson@arm.com if (is_express_snoop) 29410656Sandreas.hansson@arm.com snoops++; 2959712SN/A } 2969712SN/A 2979091SN/A return success; 2988975SN/A} 2998975SN/A 3008975SN/Abool 30110405Sandreas.hansson@arm.comCoherentXBar::recvTimingResp(PacketPtr pkt, PortID master_port_id) 3028975SN/A{ 3038975SN/A // determine the source port based on the id 3049032SN/A MasterPort *src_port = masterPorts[master_port_id]; 3058975SN/A 30610656Sandreas.hansson@arm.com // determine the destination 30710656Sandreas.hansson@arm.com const auto route_lookup = routeTo.find(pkt->req); 30810656Sandreas.hansson@arm.com assert(route_lookup != routeTo.end()); 30910656Sandreas.hansson@arm.com const PortID slave_port_id = route_lookup->second; 31010572Sandreas.hansson@arm.com assert(slave_port_id != InvalidPortID); 31110572Sandreas.hansson@arm.com assert(slave_port_id < respLayers.size()); 3129713SN/A 31310405Sandreas.hansson@arm.com // test if the crossbar should be considered occupied for the 31410405Sandreas.hansson@arm.com // current port 3159715SN/A if (!respLayers[slave_port_id]->tryTiming(src_port)) { 31610405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingResp: src %s %s 0x%x BUSY\n", 3178975SN/A src_port->name(), pkt->cmdString(), pkt->getAddr()); 3188975SN/A return false; 3198975SN/A } 3208975SN/A 32110405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingResp: src %s %s 0x%x\n", 3228975SN/A src_port->name(), pkt->cmdString(), pkt->getAddr()); 3238975SN/A 3249712SN/A // store size and command as they might be modified when 3259712SN/A // forwarding the packet 3269712SN/A unsigned int pkt_size = pkt->hasData() ? pkt->getSize() : 0; 3279712SN/A unsigned int pkt_cmd = pkt->cmdToIndex(); 3289712SN/A 32910719SMarco.Balboni@ARM.com // a response sees the response latency 33010719SMarco.Balboni@ARM.com Tick xbar_delay = responseLatency * clockPeriod(); 33110719SMarco.Balboni@ARM.com 33210719SMarco.Balboni@ARM.com // set the packet header and payload delay 33310719SMarco.Balboni@ARM.com calcPacketTiming(pkt, xbar_delay); 33410719SMarco.Balboni@ARM.com 33510719SMarco.Balboni@ARM.com // determine how long to be crossbar layer is busy 33610719SMarco.Balboni@ARM.com Tick packetFinishTime = clockEdge(Cycles(1)) + pkt->payloadDelay; 3378975SN/A 33810821Sandreas.hansson@arm.com if (snoopFilter && !system->bypassCaches()) { 33910402SN/A // let the snoop filter inspect the response and update its state 34010402SN/A snoopFilter->updateResponse(pkt, *slavePorts[slave_port_id]); 34110402SN/A } 34210402SN/A 34310888Sandreas.hansson@arm.com // send the packet through the destination slave port and pay for 34410888Sandreas.hansson@arm.com // any outstanding header delay 34510888Sandreas.hansson@arm.com Tick latency = pkt->headerDelay; 34610888Sandreas.hansson@arm.com pkt->headerDelay = 0; 34710888Sandreas.hansson@arm.com slavePorts[slave_port_id]->schedTimingResp(pkt, curTick() + latency); 3488975SN/A 34910656Sandreas.hansson@arm.com // remove the request from the routing table 35010656Sandreas.hansson@arm.com routeTo.erase(route_lookup); 35110656Sandreas.hansson@arm.com 3529715SN/A respLayers[slave_port_id]->succeededTiming(packetFinishTime); 3538975SN/A 3549712SN/A // stats updates 3559712SN/A pktCount[slave_port_id][master_port_id]++; 35610405Sandreas.hansson@arm.com pktSize[slave_port_id][master_port_id] += pkt_size; 3579712SN/A transDist[pkt_cmd]++; 3589712SN/A 3598975SN/A return true; 3608975SN/A} 3618975SN/A 3628975SN/Avoid 36310405Sandreas.hansson@arm.comCoherentXBar::recvTimingSnoopReq(PacketPtr pkt, PortID master_port_id) 3648975SN/A{ 36510405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopReq: src %s %s 0x%x\n", 3669032SN/A masterPorts[master_port_id]->name(), pkt->cmdString(), 3678975SN/A pkt->getAddr()); 3688975SN/A 3699712SN/A // update stats here as we know the forwarding will succeed 3709712SN/A transDist[pkt->cmdToIndex()]++; 37110405Sandreas.hansson@arm.com snoops++; 3729712SN/A 3738975SN/A // we should only see express snoops from caches 3748975SN/A assert(pkt->isExpressSnoop()); 3758975SN/A 37611127Sandreas.hansson@arm.com // set the packet header and payload delay, for now use forward latency 37711127Sandreas.hansson@arm.com // @todo Assess the choice of latency further 37811127Sandreas.hansson@arm.com calcPacketTiming(pkt, forwardLatency * clockPeriod()); 37911127Sandreas.hansson@arm.com 38010656Sandreas.hansson@arm.com // remeber if the packet is inhibited so we can see if it changes 38110656Sandreas.hansson@arm.com const bool is_inhibited = pkt->memInhibitAsserted(); 3829032SN/A 38311127Sandreas.hansson@arm.com assert(pkt->snoopDelay == 0); 38411127Sandreas.hansson@arm.com 38510402SN/A if (snoopFilter) { 38610402SN/A // let the Snoop Filter work its magic and guide probing 38710402SN/A auto sf_res = snoopFilter->lookupSnoop(pkt); 38811126Sandreas.hansson@arm.com // the time required by a packet to be delivered through 38911126Sandreas.hansson@arm.com // the xbar has to be charged also with to lookup latency 39011126Sandreas.hansson@arm.com // of the snoop filter 39111126Sandreas.hansson@arm.com pkt->headerDelay += sf_res.second * clockPeriod(); 39210405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopReq: src %s %s 0x%x"\ 39310402SN/A " SF size: %i lat: %i\n", masterPorts[master_port_id]->name(), 39410402SN/A pkt->cmdString(), pkt->getAddr(), sf_res.first.size(), 39510402SN/A sf_res.second); 39610402SN/A 39710402SN/A // forward to all snoopers 39810402SN/A forwardTiming(pkt, InvalidPortID, sf_res.first); 39910402SN/A } else { 40010402SN/A forwardTiming(pkt, InvalidPortID); 40110402SN/A } 4028975SN/A 40311127Sandreas.hansson@arm.com // add the snoop delay to our header delay, and then reset it 40411127Sandreas.hansson@arm.com pkt->headerDelay += pkt->snoopDelay; 40511127Sandreas.hansson@arm.com pkt->snoopDelay = 0; 40611127Sandreas.hansson@arm.com 40710656Sandreas.hansson@arm.com // if we can expect a response, remember how to route it 40810656Sandreas.hansson@arm.com if (!is_inhibited && pkt->memInhibitAsserted()) { 40910656Sandreas.hansson@arm.com assert(routeTo.find(pkt->req) == routeTo.end()); 41010656Sandreas.hansson@arm.com routeTo[pkt->req] = master_port_id; 41110656Sandreas.hansson@arm.com } 41210656Sandreas.hansson@arm.com 4138975SN/A // a snoop request came from a connected slave device (one of 4148975SN/A // our master ports), and if it is not coming from the slave 4158975SN/A // device responsible for the address range something is 4168975SN/A // wrong, hence there is nothing further to do as the packet 4178975SN/A // would be going back to where it came from 4189032SN/A assert(master_port_id == findPort(pkt->getAddr())); 4198975SN/A} 4208975SN/A 4218975SN/Abool 42210405Sandreas.hansson@arm.comCoherentXBar::recvTimingSnoopResp(PacketPtr pkt, PortID slave_port_id) 4238975SN/A{ 4248975SN/A // determine the source port based on the id 4259032SN/A SlavePort* src_port = slavePorts[slave_port_id]; 4268975SN/A 42710656Sandreas.hansson@arm.com // get the destination 42810656Sandreas.hansson@arm.com const auto route_lookup = routeTo.find(pkt->req); 42910656Sandreas.hansson@arm.com assert(route_lookup != routeTo.end()); 43010656Sandreas.hansson@arm.com const PortID dest_port_id = route_lookup->second; 43110572Sandreas.hansson@arm.com assert(dest_port_id != InvalidPortID); 4329714SN/A 4339714SN/A // determine if the response is from a snoop request we 4349714SN/A // created as the result of a normal request (in which case it 43510656Sandreas.hansson@arm.com // should be in the outstandingSnoop), or if we merely forwarded 4369714SN/A // someone else's snoop request 43710656Sandreas.hansson@arm.com const bool forwardAsSnoop = outstandingSnoop.find(pkt->req) == 43810656Sandreas.hansson@arm.com outstandingSnoop.end(); 4399714SN/A 44010405Sandreas.hansson@arm.com // test if the crossbar should be considered occupied for the 44110405Sandreas.hansson@arm.com // current port, note that the check is bypassed if the response 44210405Sandreas.hansson@arm.com // is being passed on as a normal response since this is occupying 44310405Sandreas.hansson@arm.com // the response layer rather than the snoop response layer 4449715SN/A if (forwardAsSnoop) { 44510572Sandreas.hansson@arm.com assert(dest_port_id < snoopLayers.size()); 4469715SN/A if (!snoopLayers[dest_port_id]->tryTiming(src_port)) { 44710405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopResp: src %s %s 0x%x BUSY\n", 4489715SN/A src_port->name(), pkt->cmdString(), pkt->getAddr()); 4499715SN/A return false; 4509715SN/A } 4519716SN/A } else { 4529716SN/A // get the master port that mirrors this slave port internally 4539716SN/A MasterPort* snoop_port = snoopRespPorts[slave_port_id]; 45410572Sandreas.hansson@arm.com assert(dest_port_id < respLayers.size()); 4559716SN/A if (!respLayers[dest_port_id]->tryTiming(snoop_port)) { 45610405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopResp: src %s %s 0x%x BUSY\n", 4579716SN/A snoop_port->name(), pkt->cmdString(), pkt->getAddr()); 4589716SN/A return false; 4599716SN/A } 4608975SN/A } 4618975SN/A 46210405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopResp: src %s %s 0x%x\n", 4638975SN/A src_port->name(), pkt->cmdString(), pkt->getAddr()); 4648975SN/A 4659712SN/A // store size and command as they might be modified when 4669712SN/A // forwarding the packet 4679712SN/A unsigned int pkt_size = pkt->hasData() ? pkt->getSize() : 0; 4689712SN/A unsigned int pkt_cmd = pkt->cmdToIndex(); 4699712SN/A 4708975SN/A // responses are never express snoops 4718975SN/A assert(!pkt->isExpressSnoop()); 4728975SN/A 47310719SMarco.Balboni@ARM.com // a snoop response sees the snoop response latency, and if it is 47410719SMarco.Balboni@ARM.com // forwarded as a normal response, the response latency 47510719SMarco.Balboni@ARM.com Tick xbar_delay = 47610719SMarco.Balboni@ARM.com (forwardAsSnoop ? snoopResponseLatency : responseLatency) * 47710719SMarco.Balboni@ARM.com clockPeriod(); 47810719SMarco.Balboni@ARM.com 47910719SMarco.Balboni@ARM.com // set the packet header and payload delay 48010719SMarco.Balboni@ARM.com calcPacketTiming(pkt, xbar_delay); 48110719SMarco.Balboni@ARM.com 48210719SMarco.Balboni@ARM.com // determine how long to be crossbar layer is busy 48310719SMarco.Balboni@ARM.com Tick packetFinishTime = clockEdge(Cycles(1)) + pkt->payloadDelay; 4848975SN/A 4859714SN/A // forward it either as a snoop response or a normal response 4869714SN/A if (forwardAsSnoop) { 4879714SN/A // this is a snoop response to a snoop request we forwarded, 4889714SN/A // e.g. coming from the L1 and going to the L2, and it should 4899714SN/A // be forwarded as a snoop response 49010402SN/A 49110402SN/A if (snoopFilter) { 49210402SN/A // update the probe filter so that it can properly track the line 49310402SN/A snoopFilter->updateSnoopForward(pkt, *slavePorts[slave_port_id], 49410402SN/A *masterPorts[dest_port_id]); 49510402SN/A } 49610402SN/A 4979712SN/A bool success M5_VAR_USED = 4989712SN/A masterPorts[dest_port_id]->sendTimingSnoopResp(pkt); 4999712SN/A pktCount[slave_port_id][dest_port_id]++; 50010405Sandreas.hansson@arm.com pktSize[slave_port_id][dest_port_id] += pkt_size; 5018975SN/A assert(success); 5029714SN/A 5039715SN/A snoopLayers[dest_port_id]->succeededTiming(packetFinishTime); 5043244SN/A } else { 5058975SN/A // we got a snoop response on one of our slave ports, 50610405Sandreas.hansson@arm.com // i.e. from a coherent master connected to the crossbar, and 50710405Sandreas.hansson@arm.com // since we created the snoop request as part of recvTiming, 50810405Sandreas.hansson@arm.com // this should now be a normal response again 50910656Sandreas.hansson@arm.com outstandingSnoop.erase(pkt->req); 5108948SN/A 51110656Sandreas.hansson@arm.com // this is a snoop response from a coherent master, hence it 51210656Sandreas.hansson@arm.com // should never go back to where the snoop response came from, 51310656Sandreas.hansson@arm.com // but instead to where the original request came from 5149712SN/A assert(slave_port_id != dest_port_id); 5158948SN/A 51610402SN/A if (snoopFilter) { 51710402SN/A // update the probe filter so that it can properly track the line 51810402SN/A snoopFilter->updateSnoopResponse(pkt, *slavePorts[slave_port_id], 51910402SN/A *slavePorts[dest_port_id]); 52010402SN/A } 52110402SN/A 52210405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvTimingSnoopResp: src %s %s 0x%x"\ 52310402SN/A " FWD RESP\n", src_port->name(), pkt->cmdString(), 52410402SN/A pkt->getAddr()); 52510402SN/A 5269714SN/A // as a normal response, it should go back to a master through 52710888Sandreas.hansson@arm.com // one of our slave ports, we also pay for any outstanding 52810888Sandreas.hansson@arm.com // header latency 52910888Sandreas.hansson@arm.com Tick latency = pkt->headerDelay; 53010888Sandreas.hansson@arm.com pkt->headerDelay = 0; 53110888Sandreas.hansson@arm.com slavePorts[dest_port_id]->schedTimingResp(pkt, curTick() + latency); 5329716SN/A 5339716SN/A respLayers[dest_port_id]->succeededTiming(packetFinishTime); 5343244SN/A } 5353244SN/A 53610656Sandreas.hansson@arm.com // remove the request from the routing table 53710656Sandreas.hansson@arm.com routeTo.erase(route_lookup); 53810656Sandreas.hansson@arm.com 5399712SN/A // stats updates 5409712SN/A transDist[pkt_cmd]++; 54110405Sandreas.hansson@arm.com snoops++; 5429712SN/A 5438948SN/A return true; 5448948SN/A} 5458948SN/A 5463210SN/A 5478948SN/Avoid 54810405Sandreas.hansson@arm.comCoherentXBar::forwardTiming(PacketPtr pkt, PortID exclude_slave_port_id, 54910888Sandreas.hansson@arm.com const std::vector<QueuedSlavePort*>& dests) 5508948SN/A{ 55110405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "%s for %s address %x size %d\n", __func__, 5529663SN/A pkt->cmdString(), pkt->getAddr(), pkt->getSize()); 5539663SN/A 5549524SN/A // snoops should only happen if the system isn't bypassing caches 5559524SN/A assert(!system->bypassCaches()); 5569524SN/A 55710401SN/A unsigned fanout = 0; 55810401SN/A 55910405Sandreas.hansson@arm.com for (const auto& p: dests) { 5608948SN/A // we could have gotten this request from a snooping master 5618948SN/A // (corresponding to our own slave port that is also in 5628948SN/A // snoopPorts) and should not send it back to where it came 5638948SN/A // from 5649031SN/A if (exclude_slave_port_id == InvalidPortID || 5658948SN/A p->getId() != exclude_slave_port_id) { 5668948SN/A // cache is not allowed to refuse snoop 5678975SN/A p->sendTimingSnoopReq(pkt); 56810401SN/A fanout++; 5698948SN/A } 5708948SN/A } 57110401SN/A 57210401SN/A // Stats for fanout of this forward operation 57310401SN/A snoopFanout.sample(fanout); 5742497SN/A} 5752497SN/A 5769092SN/Avoid 57710713Sandreas.hansson@arm.comCoherentXBar::recvReqRetry(PortID master_port_id) 5789092SN/A{ 5799093SN/A // responses and snoop responses never block on forwarding them, 5809093SN/A // so the retry will always be coming from a port to which we 5819093SN/A // tried to forward a request 5829715SN/A reqLayers[master_port_id]->recvRetry(); 5839092SN/A} 5849092SN/A 5859036SN/ATick 58610405Sandreas.hansson@arm.comCoherentXBar::recvAtomic(PacketPtr pkt, PortID slave_port_id) 5872657SN/A{ 58810405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvAtomic: packet src %s addr 0x%x cmd %s\n", 5899032SN/A slavePorts[slave_port_id]->name(), pkt->getAddr(), 5908949SN/A pkt->cmdString()); 5918915SN/A 59210405Sandreas.hansson@arm.com unsigned int pkt_size = pkt->hasData() ? pkt->getSize() : 0; 59310405Sandreas.hansson@arm.com unsigned int pkt_cmd = pkt->cmdToIndex(); 5949712SN/A 5958979SN/A MemCmd snoop_response_cmd = MemCmd::InvalidCmd; 5968979SN/A Tick snoop_response_latency = 0; 5978979SN/A 59810821Sandreas.hansson@arm.com if (!system->bypassCaches()) { 5998979SN/A // forward to all snoopers but the source 60010402SN/A std::pair<MemCmd, Tick> snoop_result; 60110402SN/A if (snoopFilter) { 60210402SN/A // check with the snoop filter where to forward this packet 60310402SN/A auto sf_res = 60410402SN/A snoopFilter->lookupRequest(pkt, *slavePorts[slave_port_id]); 60510402SN/A snoop_response_latency += sf_res.second * clockPeriod(); 60610405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "%s: src %s %s 0x%x"\ 60710402SN/A " SF size: %i lat: %i\n", __func__, 60810402SN/A slavePorts[slave_port_id]->name(), pkt->cmdString(), 60910402SN/A pkt->getAddr(), sf_res.first.size(), sf_res.second); 61011130Sali.jafri@arm.com 61111130Sali.jafri@arm.com // let the snoop filter know about the success of the send 61211130Sali.jafri@arm.com // operation, and do it even before sending it onwards to 61311130Sali.jafri@arm.com // avoid situations where atomic upward snoops sneak in 61411130Sali.jafri@arm.com // between and change the filter state 61511131Sandreas.hansson@arm.com snoopFilter->finishRequest(false, pkt); 61611130Sali.jafri@arm.com 61710402SN/A snoop_result = forwardAtomic(pkt, slave_port_id, InvalidPortID, 61810402SN/A sf_res.first); 61910402SN/A } else { 62010402SN/A snoop_result = forwardAtomic(pkt, slave_port_id); 62110402SN/A } 6228979SN/A snoop_response_cmd = snoop_result.first; 62310402SN/A snoop_response_latency += snoop_result.second; 6248979SN/A } 6258915SN/A 62611130Sali.jafri@arm.com // forwardAtomic snooped into peer caches of the sender, and if 62711130Sali.jafri@arm.com // this is a clean evict, but the packet is found in a cache, do 62811130Sali.jafri@arm.com // not forward it 62911130Sali.jafri@arm.com if (pkt->cmd == MemCmd::CleanEvict && pkt->isBlockCached()) { 63011130Sali.jafri@arm.com DPRINTF(CoherentXBar, "recvAtomic: Clean evict 0x%x still cached, " 63111130Sali.jafri@arm.com "not forwarding\n", pkt->getAddr()); 63211130Sali.jafri@arm.com return 0; 63311130Sali.jafri@arm.com } 63411130Sali.jafri@arm.com 6358948SN/A // even if we had a snoop response, we must continue and also 6368948SN/A // perform the actual request at the destination 63710405Sandreas.hansson@arm.com PortID master_port_id = findPort(pkt->getAddr()); 63810405Sandreas.hansson@arm.com 63910405Sandreas.hansson@arm.com // stats updates for the request 64010405Sandreas.hansson@arm.com pktCount[slave_port_id][master_port_id]++; 64110405Sandreas.hansson@arm.com pktSize[slave_port_id][master_port_id] += pkt_size; 64210405Sandreas.hansson@arm.com transDist[pkt_cmd]++; 6438948SN/A 6448948SN/A // forward the request to the appropriate destination 64510405Sandreas.hansson@arm.com Tick response_latency = masterPorts[master_port_id]->sendAtomic(pkt); 6468948SN/A 64711130Sali.jafri@arm.com // if lower levels have replied, tell the snoop filter 64811130Sali.jafri@arm.com if (!system->bypassCaches() && snoopFilter && pkt->isResponse()) { 64910402SN/A snoopFilter->updateResponse(pkt, *slavePorts[slave_port_id]); 65010402SN/A } 65110402SN/A 6528948SN/A // if we got a response from a snooper, restore it here 6538948SN/A if (snoop_response_cmd != MemCmd::InvalidCmd) { 6548948SN/A // no one else should have responded 6558948SN/A assert(!pkt->isResponse()); 6568948SN/A pkt->cmd = snoop_response_cmd; 6578948SN/A response_latency = snoop_response_latency; 6588948SN/A } 6598948SN/A 6609712SN/A // add the response data 66110405Sandreas.hansson@arm.com if (pkt->isResponse()) { 66210405Sandreas.hansson@arm.com pkt_size = pkt->hasData() ? pkt->getSize() : 0; 66310405Sandreas.hansson@arm.com pkt_cmd = pkt->cmdToIndex(); 66410405Sandreas.hansson@arm.com 66510405Sandreas.hansson@arm.com // stats updates 66610405Sandreas.hansson@arm.com pktCount[slave_port_id][master_port_id]++; 66710405Sandreas.hansson@arm.com pktSize[slave_port_id][master_port_id] += pkt_size; 66810405Sandreas.hansson@arm.com transDist[pkt_cmd]++; 66910405Sandreas.hansson@arm.com } 6709712SN/A 67110694SMarco.Balboni@ARM.com // @todo: Not setting header time 67210694SMarco.Balboni@ARM.com pkt->payloadDelay = response_latency; 6738948SN/A return response_latency; 6748948SN/A} 6758948SN/A 6768948SN/ATick 67710405Sandreas.hansson@arm.comCoherentXBar::recvAtomicSnoop(PacketPtr pkt, PortID master_port_id) 6788948SN/A{ 67910405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "recvAtomicSnoop: packet src %s addr 0x%x cmd %s\n", 6809032SN/A masterPorts[master_port_id]->name(), pkt->getAddr(), 6818949SN/A pkt->cmdString()); 6828948SN/A 6839712SN/A // add the request snoop data 68410405Sandreas.hansson@arm.com snoops++; 6859712SN/A 6868948SN/A // forward to all snoopers 68710402SN/A std::pair<MemCmd, Tick> snoop_result; 68810402SN/A Tick snoop_response_latency = 0; 68910402SN/A if (snoopFilter) { 69010402SN/A auto sf_res = snoopFilter->lookupSnoop(pkt); 69110402SN/A snoop_response_latency += sf_res.second * clockPeriod(); 69210405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, "%s: src %s %s 0x%x SF size: %i lat: %i\n", 69310402SN/A __func__, masterPorts[master_port_id]->name(), pkt->cmdString(), 69410402SN/A pkt->getAddr(), sf_res.first.size(), sf_res.second); 69510402SN/A snoop_result = forwardAtomic(pkt, InvalidPortID, master_port_id, 69610402SN/A sf_res.first); 69710402SN/A } else { 69810402SN/A snoop_result = forwardAtomic(pkt, InvalidPortID); 69910402SN/A } 7008948SN/A MemCmd snoop_response_cmd = snoop_result.first; 70110402SN/A snoop_response_latency += snoop_result.second; 7028948SN/A 7038948SN/A if (snoop_response_cmd != MemCmd::InvalidCmd) 7048948SN/A pkt->cmd = snoop_response_cmd; 7058948SN/A 7069712SN/A // add the response snoop data 70710401SN/A if (pkt->isResponse()) { 70810405Sandreas.hansson@arm.com snoops++; 70910401SN/A } 7109712SN/A 71110694SMarco.Balboni@ARM.com // @todo: Not setting header time 71210694SMarco.Balboni@ARM.com pkt->payloadDelay = snoop_response_latency; 7138948SN/A return snoop_response_latency; 7148948SN/A} 7158948SN/A 7168948SN/Astd::pair<MemCmd, Tick> 71710405Sandreas.hansson@arm.comCoherentXBar::forwardAtomic(PacketPtr pkt, PortID exclude_slave_port_id, 71810402SN/A PortID source_master_port_id, 71910888Sandreas.hansson@arm.com const std::vector<QueuedSlavePort*>& dests) 7208948SN/A{ 7219032SN/A // the packet may be changed on snoops, record the original 7229032SN/A // command to enable us to restore it between snoops so that 7238948SN/A // additional snoops can take place properly 7244626SN/A MemCmd orig_cmd = pkt->cmd; 7254879SN/A MemCmd snoop_response_cmd = MemCmd::InvalidCmd; 7264879SN/A Tick snoop_response_latency = 0; 7273662SN/A 7289524SN/A // snoops should only happen if the system isn't bypassing caches 7299524SN/A assert(!system->bypassCaches()); 7309524SN/A 73110401SN/A unsigned fanout = 0; 73210401SN/A 73310405Sandreas.hansson@arm.com for (const auto& p: dests) { 7348915SN/A // we could have gotten this request from a snooping master 7358915SN/A // (corresponding to our own slave port that is also in 7368915SN/A // snoopPorts) and should not send it back to where it came 7378915SN/A // from 73810402SN/A if (exclude_slave_port_id != InvalidPortID && 73910402SN/A p->getId() == exclude_slave_port_id) 74010402SN/A continue; 74110401SN/A 74210402SN/A Tick latency = p->sendAtomicSnoop(pkt); 74310402SN/A fanout++; 74410402SN/A 74510402SN/A // in contrast to a functional access, we have to keep on 74610402SN/A // going as all snoopers must be updated even if we get a 74710402SN/A // response 74810402SN/A if (!pkt->isResponse()) 74910402SN/A continue; 75010402SN/A 75110402SN/A // response from snoop agent 75210402SN/A assert(pkt->cmd != orig_cmd); 75310402SN/A assert(pkt->memInhibitAsserted()); 75410402SN/A // should only happen once 75510402SN/A assert(snoop_response_cmd == MemCmd::InvalidCmd); 75610402SN/A // save response state 75710402SN/A snoop_response_cmd = pkt->cmd; 75810402SN/A snoop_response_latency = latency; 75910402SN/A 76010402SN/A if (snoopFilter) { 76110402SN/A // Handle responses by the snoopers and differentiate between 76210402SN/A // responses to requests from above and snoops from below 76310402SN/A if (source_master_port_id != InvalidPortID) { 76410402SN/A // Getting a response for a snoop from below 76510402SN/A assert(exclude_slave_port_id == InvalidPortID); 76610402SN/A snoopFilter->updateSnoopForward(pkt, *p, 76710402SN/A *masterPorts[source_master_port_id]); 76810402SN/A } else { 76910402SN/A // Getting a response for a request from above 77010402SN/A assert(source_master_port_id == InvalidPortID); 77110402SN/A snoopFilter->updateSnoopResponse(pkt, *p, 77210402SN/A *slavePorts[exclude_slave_port_id]); 7734626SN/A } 7744626SN/A } 77510402SN/A // restore original packet state for remaining snoopers 77610402SN/A pkt->cmd = orig_cmd; 7774626SN/A } 7784626SN/A 77910401SN/A // Stats for fanout 78010401SN/A snoopFanout.sample(fanout); 78110401SN/A 7828948SN/A // the packet is restored as part of the loop and any potential 7838948SN/A // snoop response is part of the returned pair 7848948SN/A return std::make_pair(snoop_response_cmd, snoop_response_latency); 7852497SN/A} 7862497SN/A 7872497SN/Avoid 78810405Sandreas.hansson@arm.comCoherentXBar::recvFunctional(PacketPtr pkt, PortID slave_port_id) 7892497SN/A{ 7908663SN/A if (!pkt->isPrint()) { 7918663SN/A // don't do DPRINTFs on PrintReq as it clutters up the output 79210405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, 7938949SN/A "recvFunctional: packet src %s addr 0x%x cmd %s\n", 7949032SN/A slavePorts[slave_port_id]->name(), pkt->getAddr(), 7958663SN/A pkt->cmdString()); 7968663SN/A } 7978663SN/A 79810821Sandreas.hansson@arm.com if (!system->bypassCaches()) { 7998979SN/A // forward to all snoopers but the source 8009032SN/A forwardFunctional(pkt, slave_port_id); 8018979SN/A } 8024912SN/A 8038948SN/A // there is no need to continue if the snooping has found what we 8048948SN/A // were looking for and the packet is already a response 8058948SN/A if (!pkt->isResponse()) { 80610888Sandreas.hansson@arm.com // since our slave ports are queued ports we need to check them as well 80710888Sandreas.hansson@arm.com for (const auto& p : slavePorts) { 80810888Sandreas.hansson@arm.com // if we find a response that has the data, then the 80910888Sandreas.hansson@arm.com // downstream caches/memories may be out of date, so simply stop 81010888Sandreas.hansson@arm.com // here 81110888Sandreas.hansson@arm.com if (p->checkFunctional(pkt)) { 81210888Sandreas.hansson@arm.com if (pkt->needsResponse()) 81310888Sandreas.hansson@arm.com pkt->makeResponse(); 81410888Sandreas.hansson@arm.com return; 81510888Sandreas.hansson@arm.com } 81610888Sandreas.hansson@arm.com } 81710888Sandreas.hansson@arm.com 8189031SN/A PortID dest_id = findPort(pkt->getAddr()); 8198948SN/A 8208948SN/A masterPorts[dest_id]->sendFunctional(pkt); 8218948SN/A } 8228948SN/A} 8238948SN/A 8248948SN/Avoid 82510405Sandreas.hansson@arm.comCoherentXBar::recvFunctionalSnoop(PacketPtr pkt, PortID master_port_id) 8268948SN/A{ 8278948SN/A if (!pkt->isPrint()) { 8288948SN/A // don't do DPRINTFs on PrintReq as it clutters up the output 82910405Sandreas.hansson@arm.com DPRINTF(CoherentXBar, 8308949SN/A "recvFunctionalSnoop: packet src %s addr 0x%x cmd %s\n", 8319032SN/A masterPorts[master_port_id]->name(), pkt->getAddr(), 8328948SN/A pkt->cmdString()); 8338948SN/A } 8348948SN/A 83511188Sandreas.sandberg@arm.com for (const auto& p : slavePorts) { 83611188Sandreas.sandberg@arm.com if (p->checkFunctional(pkt)) { 83711188Sandreas.sandberg@arm.com if (pkt->needsResponse()) 83811188Sandreas.sandberg@arm.com pkt->makeResponse(); 83911188Sandreas.sandberg@arm.com return; 84011188Sandreas.sandberg@arm.com } 84111188Sandreas.sandberg@arm.com } 84211188Sandreas.sandberg@arm.com 8438948SN/A // forward to all snoopers 8449031SN/A forwardFunctional(pkt, InvalidPortID); 8458948SN/A} 8468948SN/A 8478948SN/Avoid 84810405Sandreas.hansson@arm.comCoherentXBar::forwardFunctional(PacketPtr pkt, PortID exclude_slave_port_id) 8498948SN/A{ 8509524SN/A // snoops should only happen if the system isn't bypassing caches 8519524SN/A assert(!system->bypassCaches()); 8529524SN/A 85310405Sandreas.hansson@arm.com for (const auto& p: snoopPorts) { 8548915SN/A // we could have gotten this request from a snooping master 8558915SN/A // (corresponding to our own slave port that is also in 8568915SN/A // snoopPorts) and should not send it back to where it came 8578915SN/A // from 8589031SN/A if (exclude_slave_port_id == InvalidPortID || 8598948SN/A p->getId() != exclude_slave_port_id) 8608948SN/A p->sendFunctionalSnoop(pkt); 8618915SN/A 8628948SN/A // if we get a response we are done 8638948SN/A if (pkt->isResponse()) { 8648948SN/A break; 8658915SN/A } 8663650SN/A } 8672497SN/A} 8682497SN/A 8699712SN/Avoid 87010405Sandreas.hansson@arm.comCoherentXBar::regStats() 8719712SN/A{ 87210405Sandreas.hansson@arm.com // register the stats of the base class and our layers 87310405Sandreas.hansson@arm.com BaseXBar::regStats(); 87410405Sandreas.hansson@arm.com for (auto l: reqLayers) 87510405Sandreas.hansson@arm.com l->regStats(); 87610405Sandreas.hansson@arm.com for (auto l: respLayers) 87710405Sandreas.hansson@arm.com l->regStats(); 87810405Sandreas.hansson@arm.com for (auto l: snoopLayers) 87910405Sandreas.hansson@arm.com l->regStats(); 8809712SN/A 88110405Sandreas.hansson@arm.com snoops 88210405Sandreas.hansson@arm.com .name(name() + ".snoops") 88310401SN/A .desc("Total snoops (count)") 88410401SN/A ; 88510401SN/A 88610401SN/A snoopFanout 88710401SN/A .init(0, snoopPorts.size(), 1) 88810401SN/A .name(name() + ".snoop_fanout") 88910401SN/A .desc("Request fanout histogram") 89010401SN/A ; 8919712SN/A} 8929712SN/A 89310405Sandreas.hansson@arm.comCoherentXBar * 89410405Sandreas.hansson@arm.comCoherentXBarParams::create() 8952497SN/A{ 89610405Sandreas.hansson@arm.com return new CoherentXBar(this); 8972497SN/A} 898