noncoherent_xbar.hh revision 10888:85a001f2193b
1/* 2 * Copyright (c) 2011-2015 ARM Limited 3 * All rights reserved 4 * 5 * The license below extends only to copyright in the software and shall 6 * not be construed as granting a license to any other intellectual 7 * property including but not limited to intellectual property relating 8 * to a hardware implementation of the functionality of the software 9 * licensed hereunder. You may use the software subject to the license 10 * terms below provided that you ensure that this notice is replicated 11 * unmodified and in its entirety in all distributions of the software, 12 * modified or unmodified, in source code or in binary form. 13 * 14 * Copyright (c) 2002-2005 The Regents of The University of Michigan 15 * All rights reserved. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions are 19 * met: redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer; 21 * redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution; 24 * neither the name of the copyright holders nor the names of its 25 * contributors may be used to endorse or promote products derived from 26 * this software without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 39 * 40 * Authors: Ron Dreslinski 41 * Ali Saidi 42 * Andreas Hansson 43 * William Wang 44 */ 45 46/** 47 * @file 48 * Declaration of a non-coherent crossbar. 49 */ 50 51#ifndef __MEM_NONCOHERENT_XBAR_HH__ 52#define __MEM_NONCOHERENT_XBAR_HH__ 53 54#include "mem/xbar.hh" 55#include "params/NoncoherentXBar.hh" 56 57/** 58 * A non-coherent crossbar connects a number of non-snooping masters 59 * and slaves, and routes the request and response packets based on 60 * the address. The request packets issued by the master connected to 61 * a non-coherent crossbar could still snoop in caches attached to a 62 * coherent crossbar, as is the case with the I/O bus and memory bus 63 * in most system configurations. No snoops will, however, reach any 64 * master on the non-coherent crossbar itself. 65 * 66 * The non-coherent crossbar can be used as a template for modelling 67 * PCIe, and non-coherent AMBA and OCP buses, and is typically used 68 * for the I/O buses. 69 */ 70class NoncoherentXBar : public BaseXBar 71{ 72 73 protected: 74 75 /** 76 * Declare the layers of this crossbar, one vector for requests 77 * and one for responses. 78 */ 79 std::vector<ReqLayer*> reqLayers; 80 std::vector<RespLayer*> respLayers; 81 82 /** 83 * Declaration of the non-coherent crossbar slave port type, one 84 * will be instantiated for each of the master ports connecting to 85 * the crossbar. 86 */ 87 class NoncoherentXBarSlavePort : public QueuedSlavePort 88 { 89 private: 90 91 /** A reference to the crossbar to which this port belongs. */ 92 NoncoherentXBar &xbar; 93 94 /** A normal packet queue used to store responses. */ 95 RespPacketQueue queue; 96 97 public: 98 99 NoncoherentXBarSlavePort(const std::string &_name, 100 NoncoherentXBar &_xbar, PortID _id) 101 : QueuedSlavePort(_name, &_xbar, queue, _id), xbar(_xbar), 102 queue(_xbar, *this) 103 { } 104 105 protected: 106 107 /** 108 * When receiving a timing request, pass it to the crossbar. 109 */ 110 virtual bool recvTimingReq(PacketPtr pkt) 111 { return xbar.recvTimingReq(pkt, id); } 112 113 /** 114 * When receiving an atomic request, pass it to the crossbar. 115 */ 116 virtual Tick recvAtomic(PacketPtr pkt) 117 { return xbar.recvAtomic(pkt, id); } 118 119 /** 120 * When receiving a functional request, pass it to the crossbar. 121 */ 122 virtual void recvFunctional(PacketPtr pkt) 123 { xbar.recvFunctional(pkt, id); } 124 125 /** 126 * Return the union of all adress ranges seen by this crossbar. 127 */ 128 virtual AddrRangeList getAddrRanges() const 129 { return xbar.getAddrRanges(); } 130 131 }; 132 133 /** 134 * Declaration of the crossbar master port type, one will be 135 * instantiated for each of the slave ports connecting to the 136 * crossbar. 137 */ 138 class NoncoherentXBarMasterPort : public MasterPort 139 { 140 private: 141 142 /** A reference to the crossbar to which this port belongs. */ 143 NoncoherentXBar &xbar; 144 145 public: 146 147 NoncoherentXBarMasterPort(const std::string &_name, 148 NoncoherentXBar &_xbar, PortID _id) 149 : MasterPort(_name, &_xbar, _id), xbar(_xbar) 150 { } 151 152 protected: 153 154 /** 155 * When receiving a timing response, pass it to the crossbar. 156 */ 157 virtual bool recvTimingResp(PacketPtr pkt) 158 { return xbar.recvTimingResp(pkt, id); } 159 160 /** When reciving a range change from the peer port (at id), 161 pass it to the crossbar. */ 162 virtual void recvRangeChange() 163 { xbar.recvRangeChange(id); } 164 165 /** When reciving a retry from the peer port (at id), 166 pass it to the crossbar. */ 167 virtual void recvReqRetry() 168 { xbar.recvReqRetry(id); } 169 170 }; 171 172 /** Function called by the port when the crossbar is recieving a Timing 173 request packet.*/ 174 virtual bool recvTimingReq(PacketPtr pkt, PortID slave_port_id); 175 176 /** Function called by the port when the crossbar is recieving a Timing 177 response packet.*/ 178 virtual bool recvTimingResp(PacketPtr pkt, PortID master_port_id); 179 180 /** Timing function called by port when it is once again able to process 181 * requests. */ 182 void recvReqRetry(PortID master_port_id); 183 184 /** Function called by the port when the crossbar is recieving a Atomic 185 transaction.*/ 186 Tick recvAtomic(PacketPtr pkt, PortID slave_port_id); 187 188 /** Function called by the port when the crossbar is recieving a Functional 189 transaction.*/ 190 void recvFunctional(PacketPtr pkt, PortID slave_port_id); 191 192 public: 193 194 NoncoherentXBar(const NoncoherentXBarParams *p); 195 196 virtual ~NoncoherentXBar(); 197 198 unsigned int drain(DrainManager *dm); 199 200 /** 201 * stats 202 */ 203 virtual void regStats(); 204 Stats::Scalar totPktSize; 205}; 206 207#endif //__MEM_NONCOHERENT_XBAR_HH__ 208