noncoherent_xbar.hh revision 2665 
1/*
2 * Copyright (c) 2002-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Ron Dreslinski
29 */
30
31/**
32 * @file Decleration of a bus object.
33 */
34
35#ifndef __MEM_BUS_HH__
36#define __MEM_BUS_HH__
37
38#include <string>
39#include <list>
40#include <inttypes.h>
41
42#include "base/range.hh"
43#include "mem/mem_object.hh"
44#include "mem/packet.hh"
45#include "mem/port.hh"
46#include "mem/request.hh"
47
48class Bus : public MemObject
49{
50    /** a globally unique id for this bus. */
51    int busId;
52
53    struct DevMap {
54        int portId;
55        Range<Addr> range;
56    };
57    std::vector<DevMap> portList;
58
59
60    /** Function called by the port when the bus is recieving a Timing
61        transaction.*/
62    bool recvTiming(Packet *pkt);
63
64    /** Function called by the port when the bus is recieving a Atomic
65        transaction.*/
66    Tick recvAtomic(Packet *pkt);
67
68    /** Function called by the port when the bus is recieving a Functional
69        transaction.*/
70    void recvFunctional(Packet *pkt);
71
72    /** Timing function called by port when it is once again able to process
73     * requests. */
74    void recvRetry(int id);
75
76    /** Function called by the port when the bus is recieving a status change.*/
77    void recvStatusChange(Port::Status status, int id);
78
79    /** Find which port connected to this bus (if any) should be given a packet
80     * with this address.
81     * @param addr Address to find port for.
82     * @param id Id of the port this packet was received from (to prevent
83     *             loops)
84     * @return pointer to port that the packet should be sent out of.
85     */
86    Port *findPort(Addr addr, int id);
87
88    /** Process address range request.
89     * @param resp addresses that we can respond to
90     * @param snoop addresses that we would like to snoop
91     * @param id ide of the busport that made the request.
92     */
93    void addressRanges(AddrRangeList &resp, AddrRangeList &snoop, int id);
94
95
96    /** Decleration of the buses port type, one will be instantiated for each
97        of the interfaces connecting to the bus. */
98    class BusPort : public Port
99    {
100        /** A pointer to the bus to which this port belongs. */
101        Bus *bus;
102
103        /** A id to keep track of the intercafe ID this port is connected to. */
104        int id;
105
106      public:
107
108        /** Constructor for the BusPort.*/
109        BusPort(const std::string &_name, Bus *_bus, int _id)
110            : Port(_name), bus(_bus), id(_id)
111        { }
112
113      protected:
114
115        /** When reciving a timing request from the peer port (at id),
116            pass it to the bus. */
117        virtual bool recvTiming(Packet *pkt)
118        { pkt->setSrc(id); return bus->recvTiming(pkt); }
119
120        /** When reciving a Atomic requestfrom the peer port (at id),
121            pass it to the bus. */
122        virtual Tick recvAtomic(Packet *pkt)
123        { pkt->setSrc(id); return bus->recvAtomic(pkt); }
124
125        /** When reciving a Functional requestfrom the peer port (at id),
126            pass it to the bus. */
127        virtual void recvFunctional(Packet *pkt)
128        { pkt->setSrc(id); bus->recvFunctional(pkt); }
129
130        /** When reciving a status changefrom the peer port (at id),
131            pass it to the bus. */
132        virtual void recvStatusChange(Status status)
133        { bus->recvStatusChange(status, id); }
134
135        /** When reciving a retry from the peer port (at id),
136            pass it to the bus. */
137        virtual void recvRetry()
138        { bus->recvRetry(id); }
139
140        // This should return all the 'owned' addresses that are
141        // downstream from this bus, yes?  That is, the union of all
142        // the 'owned' address ranges of all the other interfaces on
143        // this bus...
144        virtual void getDeviceAddressRanges(AddrRangeList &resp,
145                                            AddrRangeList &snoop)
146        { bus->addressRanges(resp, snoop, id); }
147
148        // Hack to make translating port work without changes
149        virtual int deviceBlockSize() { return 32; }
150
151    };
152
153    /** An array of pointers to the peer port interfaces
154        connected to this bus.*/
155    std::vector<Port*> interfaces;
156
157    /** An array of pointers to ports that retry should be called on because the
158     * original send failed for whatever reason.*/
159    std::list<Port*> retryList;
160
161  public:
162
163    /** A function used to return the port associated with this bus object. */
164    virtual Port *getPort(const std::string &if_name);
165
166    virtual void init();
167
168    Bus(const std::string &n, int bus_id)
169        : MemObject(n), busId(bus_id)  {}
170
171};
172
173#endif //__MEM_BUS_HH__
174