src/mem/protocol/MOESI_CMP_directory-msg.sm

/*
 * Copyright (c) 2019 ARM Limited
 * All rights reserved
 *
 * The license below extends only to copyright in the software and shall
 * not be construed as granting a license to any other intellectual
 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
 * unmodified and in its entirety in all distributions of the software,
 * modified or unmodified, in source code or in binary form.
 *
 * Copyright (c) 1999-2005 Mark D. Hill and David A. Wood
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met: redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer;
 * redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution;
 * neither the name of the copyright holders nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * $Id$
 *
 */

// CoherenceRequestType
enumeration(CoherenceRequestType, desc="...") {
  GETX,      desc="Get eXclusive";
  GETS,      desc="Get Shared";
  PUTX,      desc="Put eXclusive";
  PUTO,      desc="Put Owned";
  PUTO_SHARERS,      desc="Put Owned, but sharers exist so don't remove from sharers list";
  PUTS,      desc="Put Shared";
  INV,       desc="Invalidation";
  WRITEBACK_CLEAN_DATA,   desc="Clean writeback (contains data)";
  WRITEBACK_CLEAN_ACK,    desc="Clean writeback (contains no data)";
  WRITEBACK_DIRTY_DATA,   desc="Dirty writeback (contains data)";
  DMA_READ,  desc="DMA Read";
  DMA_WRITE, desc="DMA Write";
}

// CoherenceResponseType
enumeration(CoherenceResponseType, desc="...") {
  ACK,               desc="ACKnowledgment, responder doesn't have a copy";
  DATA,              desc="Data";
  DATA_EXCLUSIVE,    desc="Data, no processor has a copy";
  UNBLOCK,           desc="Unblock";
  UNBLOCK_EXCLUSIVE, desc="Unblock, we're in E/M";
  WB_ACK,            desc="Writeback ack";
  WB_ACK_DATA,       desc="Writeback ack";
  WB_NACK,           desc="Writeback neg. ack";
  DMA_ACK,           desc="Ack that a DMA write completed";
}

// TriggerType
enumeration(TriggerType, desc="...") {
  ALL_ACKS,            desc="See corresponding event";
}

// TriggerMsg
structure(TriggerMsg, desc="...", interface="Message") {
  Addr addr,             desc="Physical address for this request";
  TriggerType Type,            desc="Type of trigger";

  bool functionalRead(Packet *pkt) {
    // Trigger message does not hold data
    return false;
  }

  bool functionalWrite(Packet *pkt) {
    // Trigger message does not hold data
    return false;
  }
}

// RequestMsg (and also forwarded requests)
structure(RequestMsg, desc="...", interface="Message") {
  Addr addr,             desc="Physical address for this request";
  int Len,                     desc="Length of Request";
  CoherenceRequestType Type,   desc="Type of request (GetS, GetX, PutX, etc)";
  MachineID Requestor,            desc="Node who initiated the request";
  MachineType RequestorMachine,   desc="type of component";
  NetDest Destination,             desc="Multicast destination mask";
  DataBlock DataBlk,           desc="data for the cache line (DMA WRITE request)";
  int Acks,                    desc="How many acks to expect";
  MessageSizeType MessageSize, desc="size category of the message";
  RubyAccessMode AccessMode,    desc="user/supervisor access type";
  PrefetchBit Prefetch,         desc="Is this a prefetch request";

  bool functionalRead(Packet *pkt) {
    // Read only those messages that contain the data
    if (Type == CoherenceRequestType:DMA_READ ||
        Type == CoherenceRequestType:DMA_WRITE ||
        Type == CoherenceRequestType:WRITEBACK_CLEAN_DATA ||
        Type == CoherenceRequestType:WRITEBACK_DIRTY_DATA) {
        return testAndRead(addr, DataBlk, pkt);
    }
    return false;
  }

  bool functionalWrite(Packet *pkt) {
    // No check required since all messages are written
    return testAndWrite(addr, DataBlk, pkt);
  }
}

// ResponseMsg (and also unblock requests)
structure(ResponseMsg, desc="...", interface="Message") {
  Addr addr,             desc="Physical address for this request";
  CoherenceResponseType Type,  desc="Type of response (Ack, Data, etc)";
  MachineID Sender,               desc="Node who sent the data";
  MachineType SenderMachine,   desc="type of component sending msg";
  NetDest Destination,             desc="Node to whom the data is sent";
  DataBlock DataBlk,           desc="data for the cache line";
  bool Dirty,                  desc="Is the data dirty (different than memory)?";
  int Acks,                    desc="How many acks to expect";
  MessageSizeType MessageSize, desc="size category of the message";

  bool functionalRead(Packet *pkt) {
    // Read only those messages that contain the data
    if (Type == CoherenceResponseType:DATA ||
        Type == CoherenceResponseType:DATA_EXCLUSIVE) {
        return testAndRead(addr, DataBlk, pkt);
    }
    return false;
  }

  bool functionalWrite(Packet *pkt) {
    // No check required since all messages are written
    return testAndWrite(addr, DataBlk, pkt);
  }
}