xbar.cc revision 2568 
1/*
2 * Copyright (c) 2006 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
29/**
30 * @file Definition of a bus object.
31 */
32
33
34#include "base/trace.hh"
35#include "mem/bus.hh"
36#include "sim/builder.hh"
37
38/** Get the ranges of anyone that we are connected to. */
39void
40Bus::init()
41{
42    std::vector<Port*>::iterator intIter;
43    for (intIter = interfaces.begin(); intIter != interfaces.end(); intIter++)
44        (*intIter)->sendStatusChange(Port::RangeChange);
45}
46
47
48/** Function called by the port when the bus is recieving a Timing
49 * transaction.*/
50bool
51Bus::recvTiming(Packet &pkt, int id)
52{
53    return findPort(pkt.addr, id)->sendTiming(pkt);
54}
55
56Port *
57Bus::findPort(Addr addr, int id)
58{
59    /* An interval tree would be a better way to do this. --ali. */
60    int dest_id = -1;
61    int i = 0;
62    bool found = false;
63
64    while (i < portList.size() && !found)
65    {
66        if (portList[i].range == addr) {
67            dest_id = portList[i].portId;
68            found = true;
69            DPRINTF(Bus, "Found Addr: %llx on device %d\n", addr, dest_id);
70        }
71        i++;
72    }
73    if (dest_id == -1)
74        panic("Unable to find destination for addr: %llx", addr);
75
76    // we shouldn't be sending this back to where it came from
77    assert(dest_id != id);
78
79    return interfaces[dest_id];
80}
81
82/** Function called by the port when the bus is recieving a Atomic
83 * transaction.*/
84Tick
85Bus::recvAtomic(Packet &pkt, int id)
86{
87    return findPort(pkt.addr, id)->sendAtomic(pkt);
88}
89
90/** Function called by the port when the bus is recieving a Functional
91 * transaction.*/
92void
93Bus::recvFunctional(Packet &pkt, int id)
94{
95    findPort(pkt.addr, id)->sendFunctional(pkt);
96}
97
98/** Function called by the port when the bus is recieving a status change.*/
99void
100Bus::recvStatusChange(Port::Status status, int id)
101{
102    DPRINTF(Bus, "Bus %d recieved status change from device id %d\n",
103            busId, id);
104    assert(status == Port::RangeChange &&
105           "The other statuses need to be implemented.");
106
107    assert(id < interfaces.size() && id >= 0);
108    int x;
109    Port *port = interfaces[id];
110    AddrRangeList ranges;
111    AddrRangeList snoops;
112    AddrRangeIter iter;
113    std::vector<DevMap>::iterator portIter;
114
115    // Clean out any previously existent ids
116    for (portIter = portList.begin(); portIter != portList.end(); ) {
117        if (portIter->portId == id)
118            portIter = portList.erase(portIter);
119        else
120            portIter++;
121    }
122
123    port->getPeerAddressRanges(ranges, snoops);
124
125    // not dealing with snooping yet either
126    assert(snoops.size() == 0);
127    for(iter = ranges.begin(); iter != ranges.end(); iter++) {
128        DevMap dm;
129        dm.portId = id;
130        dm.range = *iter;
131
132        DPRINTF(MMU, "Adding range %llx - %llx for id %d\n", dm.range.start,
133                dm.range.end, id);
134        portList.push_back(dm);
135    }
136    DPRINTF(MMU, "port list has %d entries\n", portList.size());
137
138    // tell all our peers that our address range has changed.
139    // Don't tell the device that caused this change, it already knows
140    for (x = 0; x < interfaces.size(); x++)
141        if (x != id)
142            interfaces[x]->sendStatusChange(Port::RangeChange);
143}
144
145void
146Bus::addressRanges(AddrRangeList &resp, AddrRangeList &snoop, int id)
147{
148    std::vector<DevMap>::iterator portIter;
149
150    resp.clear();
151    snoop.clear();
152
153    DPRINTF(Bus, "Bus id %d recieved address range request returning\n",
154            busId);
155    for (portIter = portList.begin(); portIter != portList.end(); portIter++) {
156        if (portIter->portId != id) {
157            resp.push_back(portIter->range);
158            DPRINTF(Bus, "-- %#llX : %#llX\n", portIter->range.start,
159                    portIter->range.end);
160        }
161    }
162}
163
164BEGIN_DECLARE_SIM_OBJECT_PARAMS(Bus)
165
166    Param<int> bus_id;
167
168END_DECLARE_SIM_OBJECT_PARAMS(Bus)
169
170BEGIN_INIT_SIM_OBJECT_PARAMS(Bus)
171    INIT_PARAM(bus_id, "a globally unique bus id")
172END_INIT_SIM_OBJECT_PARAMS(Bus)
173
174CREATE_SIM_OBJECT(Bus)
175{
176    return new Bus(getInstanceName(), bus_id);
177}
178
179REGISTER_SIM_OBJECT("Bus", Bus)
180