summaryrefslogtreecommitdiff
path: root/src/mem/external_slave.hh
blob: 2bb0be869ecf2b7c92dba7edbb2d3838e29c57e0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
/*
 * Copyright (c) 2012-2014 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.
 *
 * 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.
 *
 * Authors: Andrew Bardsley
 */

/**
 * @file
 *
 * ExternalSlave is a memory object representing a binding from
 * a gem5 master to a slave port in a system external to gem5.
 *
 * During initialisation, a `handler' for the port type specified in the
 * port's port_type parameter is found from the registered port handlers
 * provided with registerHandler.  Once a handler is found, it is passed the
 * port_data parameter of the port which can be used to identify the external
 * port which is to be bound to.  A port handler will usually construct a
 * bridge object in the external system to accomodate the port-to-port
 * mapping but this bridge is not exposed to gem5 other than be the
 * presentation of the SlavePort which can be bound.
 *
 * The external port must provide a gem5 SlavePort interface (with the
 * exception of getAddrRanges which is provided by the ExternalSlave
 * object).
 */

#ifndef __MEM_EXTERNAL_SLAVE_HH__
#define __MEM_EXTERNAL_SLAVE_HH__

#include "mem/mem_object.hh"
#include "params/ExternalSlave.hh"

class ExternalSlave : public MemObject
{
  public:
    /** Derive from this class to create an external port interface */
    class Port : public SlavePort
    {
      protected:
        ExternalSlave &owner;

      public:
        Port(const std::string &name_,
            ExternalSlave &owner_) :
            SlavePort(name_, &owner_), owner(owner_)
        { }

        ~Port() { }

        /** Any or all of recv... can be overloaded to provide the port's
         *  functionality */

        AddrRangeList getAddrRanges() const;
    };

    /* Handlers are specific to *types* of port not specific port
     * instantiations.  A handler will typically build a bridge to the
     * external port from gem5 and provide gem5 with a SlavePort that can be
     * bound to for each call to Handler::getExternalPort.*/
    class Handler
    {
      public:
        /** Create or find an external port which can be bound.  Returns
         *  NULL on failure */
        virtual Port *getExternalPort(
            const std::string &name, ExternalSlave &owner,
            const std::string &port_data) = 0;
    };

  protected:
    /** The peer port for the gem5 port "port" */
    Port *externalPort;

    /** Name of the bound port.  This will be name() + ".port" */
    std::string portName;

    /** Key to select a port handler */
    std::string portType;

    /** Handler-specific port configuration */
    std::string portData;

    /** The Range of addresses supported by the devices on the external
     *  side of this port */
    AddrRangeList addrRanges;

    /** Registered handlers.  Handlers are chosen using the port_type
     *  parameter on ExternalSlaves.  port_types form a global namespace
     *  across the simulation and so handlers are registered into a global
     *  structure */
    static std::map<std::string, Handler *> portHandlers;

  public:
    ExternalSlave(ExternalSlaveParams *params);

    /** SlavePort interface.  Responds only to port "port" */
    BaseSlavePort &getSlavePort(const std::string &if_name,
        PortID idx = InvalidPortID);

    /** Register a handler which can provide ports with port_type ==
     *  handler_name */
    static void registerHandler(const std::string &handler_name,
        Handler *handler);

    void init();
};


#endif //__MEM_EXTERNAL_SLAVE_HH__