src/mem/external_slave.cc

   1 /*
   2  * Copyright (c) 2012-2014 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  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions are
  16  * met: redistributions of source code must retain the above copyright
  17  * notice, this list of conditions and the following disclaimer;
  18  * redistributions in binary form must reproduce the above copyright
  19  * notice, this list of conditions and the following disclaimer in the
  20  * documentation and/or other materials provided with the distribution;
  21  * neither the name of the copyright holders nor the names of its
  22  * contributors may be used to endorse or promote products derived from
  23  * this software without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  27  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  28  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  29  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  31  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  35  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 #include "mem/external_slave.hh"
  39
  40 #include <cctype>
  41 #include <iomanip>
  42
  43 #include "base/trace.hh"
  44 #include "debug/ExternalPort.hh"
  45
  46 /** Implement a `stub' port which just responds to requests by printing
  47  *  a message.  The stub port can be used to configure and test a system
  48  *  where the external port is used for a peripheral before connecting
  49  *  the external port */
  50 class StubSlavePort : public ExternalSlave::ExternalPort
  51 {
  52   public:
  53     void processResponseEvent();
  54
  55     EventFunctionWrapper responseEvent;
  56
  57     /** Stub can handle a single request at a time.  This will be
  58      *  NULL when no packet is in flight */
  59     PacketPtr responsePacket;
  60
  61     /** Received a new request while processing a first.  Need to ask for
  62      *  a retry after completing this packet */
  63     bool mustRetry;
  64
  65     StubSlavePort(const std::string &name_,
  66         ExternalSlave &owner_) :
  67         ExternalSlave::ExternalPort(name_, owner_),
  68         responseEvent([this]{ processResponseEvent(); }, name()),
  69         responsePacket(NULL), mustRetry(false)
  70     { }
  71
  72     Tick recvAtomic(PacketPtr packet);
  73     void recvFunctional(PacketPtr packet);
  74     bool recvTimingReq(PacketPtr packet);
  75     bool recvTimingSnoopResp(PacketPtr packet);
  76     void recvRespRetry();
  77     void recvFunctionalSnoop(PacketPtr packet);
  78 };
  79
  80 class StubSlavePortHandler : public
  81     ExternalSlave::Handler
  82 {
  83   public:
  84     ExternalSlave::ExternalPort *getExternalPort(
  85         const std::string &name_,
  86         ExternalSlave &owner,
  87         const std::string &port_data)
  88     {
  89         StringWrap name(name_);
  90
  91         DPRINTF(ExternalPort, "finding stub port '%s'\n", port_data);
  92         return new StubSlavePort(name_, owner);
  93     }
  94 };
  95
  96 Tick
  97 StubSlavePort::recvAtomic(PacketPtr packet)
  98 {
  99     if (DTRACE(ExternalPort)) {
 100         M5_VAR_USED unsigned int size = packet->getSize();
 101
 102         DPRINTF(ExternalPort, "StubSlavePort: recvAtomic a: 0x%x size: %d"
 103             " data: ...\n", packet->getAddr(), size);
 104         DDUMP(ExternalPort, packet->getConstPtr<uint8_t>(), size);
 105     }
 106
 107     return 0;
 108 }
 109
 110 void
 111 StubSlavePort::recvFunctional(PacketPtr packet)
 112 {
 113     recvAtomic(packet);
 114 }
 115
 116 void
 117 StubSlavePort::processResponseEvent()
 118 {
 119     responsePacket->makeResponse();
 120     responsePacket->headerDelay = 0;
 121     responsePacket->payloadDelay = 0;
 122
 123     if (sendTimingResp(responsePacket)) {
 124         responsePacket = NULL;
 125
 126         if (mustRetry)
 127             sendRetryReq();
 128         mustRetry = false;
 129     }
 130 }
 131
 132 bool
 133 StubSlavePort::recvTimingReq(PacketPtr packet)
 134 {
 135     if (responsePacket) {
 136         mustRetry = true;
 137
 138         return false;
 139     } else {
 140         recvAtomic(packet);
 141
 142         responsePacket = packet;
 143         owner.schedule(responseEvent, curTick());
 144
 145         return true;
 146     }
 147 }
 148
 149 bool
 150 StubSlavePort::recvTimingSnoopResp(PacketPtr packet)
 151 {
 152     fatal("StubSlavePort: function: %s\n", __func__);
 153     return false;
 154 }
 155
 156 void
 157 StubSlavePort::recvRespRetry()
 158 {
 159     assert(responsePacket);
 160     /* Stub handles only one response at a time so responseEvent should never
 161      *  be scheduled at this point.  Retrys shouldn't need to schedule, we
 162      *  can safely send the response here */
 163     responseEvent.process();
 164 }
 165
 166 void
 167 StubSlavePort::recvFunctionalSnoop(PacketPtr packet)
 168 {
 169     fatal("StubSlavePort: unimplemented function: %s\n", __func__);
 170 }
 171
 172 std::map<std::string, ExternalSlave::Handler *>
 173     ExternalSlave::portHandlers;
 174
 175 AddrRangeList
 176 ExternalSlave::ExternalPort::getAddrRanges() const
 177 {
 178     return owner.addrRanges;
 179 }
 180
 181 ExternalSlave::ExternalSlave(const ExternalSlaveParams &params) :
 182     SimObject(params),
 183     externalPort(NULL),
 184     portName(params.name + ".port"),
 185     portType(params.port_type),
 186     portData(params.port_data),
 187     addrRanges(params.addr_ranges.begin(), params.addr_ranges.end())
 188 {
 189     /* Register the stub handler if it hasn't already been registered */
 190     if (portHandlers.find("stub") == portHandlers.end())
 191         registerHandler("stub", new StubSlavePortHandler);
 192 }
 193
 194 Port &
 195 ExternalSlave::getPort(const std::string &if_name, PortID idx)
 196 {
 197     if (if_name == "port") {
 198         DPRINTF(ExternalPort, "Trying to bind external port: %s %s\n",
 199             portType, portName);
 200
 201         if (!externalPort) {
 202             auto handlerIter = portHandlers.find(portType);
 203
 204             if (handlerIter == portHandlers.end())
 205                 fatal("Can't find port handler type '%s'\n", portType);
 206
 207             externalPort = portHandlers[portType]->getExternalPort(portName,
 208                 *this, portData);
 209
 210             if (!externalPort) {
 211                 fatal("%s: Can't find external port type: %s"
 212                     " port_data: '%s'\n", portName, portType, portData);
 213             }
 214         }
 215         return *externalPort;
 216     } else {
 217         return SimObject::getPort(if_name, idx);
 218     }
 219 }
 220
 221 void
 222 ExternalSlave::init()
 223 {
 224     if (!externalPort) {
 225         fatal("ExternalSlave %s: externalPort not set!\n", name());
 226     } else if (!externalPort->isConnected()) {
 227         fatal("ExternalSlave %s is unconnected!\n", name());
 228     } else {
 229         externalPort->sendRangeChange();
 230     }
 231 }
 232
 233 void
 234 ExternalSlave::registerHandler(const std::string &handler_name,
 235     Handler *handler)
 236 {
 237     portHandlers[handler_name] = handler;
 238 }