1/*
2 * Copyright (c) 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 * 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 * Authors: Gabor Dozsa
38 */
39
40/* @file
41 * Header packet class for dist-gem5 runs.
42 *
43 * For a high level description about dist-gem5 see comments in
44 * header file dist_iface.hh.
45 *
46 * The DistHeaderPkt class defines the format of message headers
47 * sent among gem5 processes during a dist gem5 simulation. A header packet
48 * can either carry the description of data packet (i.e. a simulated Ethernet
49 * packet) or a synchronisation related control command. In case of
50 * data packet description, the corresponding data packet always follows
51 * the header packet back-to-back.
52 */
53#ifndef __DEV_DIST_PACKET_HH__
54#define __DEV_DIST_PACKET_HH__
55
56#include <cstring>
57
58#include "base/types.hh"
59
60class DistHeaderPkt
61{
62  private:
63    DistHeaderPkt() {}
64    ~DistHeaderPkt() {}
65
66  public:
67    enum class ReqType { immediate, collective, pending, none };
68    /**
69     *  The msg type defines what information a dist header packet carries.
70     */
71    enum class MsgType
72    {
73        dataDescriptor,
74        cmdSyncReq,
75        cmdSyncAck,
76        unknown
77    };
78
79    struct Header
80    {
81        /**
82         * The msg type field is valid for all header packets.
83         *
84         * @note senderRank is used with data packets while collFlags are used
85         * by sync ack messages to trigger collective ckpt or exit events.
86         */
87        MsgType msgType;
88        Tick sendTick;
89        /**
90         * Length used for modeling timing in the simulator.
91         * (from EthPacketData::simLength).
92         */
93        unsigned simLength;
94        union {
95            Tick sendDelay;
96            Tick syncRepeat;
97        };
98        union {
99            /**
100             * Actual length of the simulated Ethernet packet.
101             * (from EthPacketData::length).
102             */
103            unsigned dataPacketLength;
104            struct {
105                ReqType needCkpt;
106                ReqType needStopSync;
107                ReqType needExit;
108            };
109        };
110    };
111};
112
113#endif
114