etherlink.hh revision 11168 
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 * 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: Nathan Binkert
41 */
42
43/* @file
44 * Device module for modelling a fixed bandwidth full duplex ethernet link
45 */
46
47#ifndef __DEV_ETHERLINK_HH__
48#define __DEV_ETHERLINK_HH__
49
50#include <queue>
51
52#include "base/types.hh"
53#include "dev/etherint.hh"
54#include "dev/etherobject.hh"
55#include "dev/etherpkt.hh"
56#include "params/EtherLink.hh"
57#include "sim/eventq.hh"
58#include "sim/sim_object.hh"
59
60class EtherDump;
61class Checkpoint;
62/*
63 * Model for a fixed bandwidth full duplex ethernet link
64 */
65class EtherLink : public EtherObject
66{
67  protected:
68    class Interface;
69
70    /*
71     * Model for a single uni-directional link
72     */
73    class Link
74    {
75      protected:
76        const std::string objName;
77
78        EtherLink *const parent;
79        const int number;
80
81        Interface *txint;
82        Interface *rxint;
83
84        const double ticksPerByte;
85        const Tick linkDelay;
86        const Tick delayVar;
87        EtherDump *const dump;
88
89      protected:
90        /*
91         * Transfer is complete
92         */
93        EthPacketPtr packet;
94        void txDone();
95        typedef EventWrapper<Link, &Link::txDone> DoneEvent;
96        friend void DoneEvent::process();
97        DoneEvent doneEvent;
98
99        /**
100         * Maintain a queue of in-flight packets. Assume that the
101         * delay is non-zero and constant (i.e., at most one packet
102         * per tick).
103         */
104        std::deque<std::pair<Tick, EthPacketPtr>> txQueue;
105
106        void processTxQueue();
107        typedef EventWrapper<Link, &Link::processTxQueue> TxQueueEvent;
108        friend void TxQueueEvent::process();
109        TxQueueEvent txQueueEvent;
110
111        void txComplete(EthPacketPtr packet);
112
113      public:
114        Link(const std::string &name, EtherLink *p, int num,
115             double rate, Tick delay, Tick delay_var, EtherDump *dump);
116        ~Link() {}
117
118        const std::string name() const { return objName; }
119
120        bool busy() const { return (bool)packet; }
121        bool transmit(EthPacketPtr packet);
122
123        void setTxInt(Interface *i) { assert(!txint); txint = i; }
124        void setRxInt(Interface *i) { assert(!rxint); rxint = i; }
125
126        void serialize(const std::string &base, CheckpointOut &cp) const;
127        void unserialize(const std::string &base, CheckpointIn &cp);
128    };
129
130    /*
131     * Interface at each end of the link
132     */
133    class Interface : public EtherInt
134    {
135      private:
136        Link *txlink;
137
138      public:
139        Interface(const std::string &name, Link *txlink, Link *rxlink);
140        bool recvPacket(EthPacketPtr packet) { return txlink->transmit(packet); }
141        void sendDone() { peer->sendDone(); }
142        bool isBusy() { return txlink->busy(); }
143    };
144
145    Link *link[2];
146    Interface *interface[2];
147
148  public:
149    typedef EtherLinkParams Params;
150    EtherLink(const Params *p);
151    virtual ~EtherLink();
152
153    const Params *
154    params() const
155    {
156        return dynamic_cast<const Params *>(_params);
157    }
158
159    virtual EtherInt *getEthPort(const std::string &if_name, int idx);
160
161    void serialize(CheckpointOut &cp) const override;
162    void unserialize(CheckpointIn &cp) override;
163
164};
165
166#endif // __ETHERLINK_HH__
167