packet.cc revision 3260:d9ef6d4cbe2a 
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 * Authors: Ali Saidi
29 *          Steve Reinhardt
30 */
31
32/**
33 * @file
34 * Definition of the Packet Class, a packet is a transaction occuring
35 * between a single level of the memory heirarchy (ie L1->L2).
36 */
37
38#include <iostream>
39#include "base/misc.hh"
40#include "mem/packet.hh"
41#include "base/trace.hh"
42
43static const std::string ReadReqString("ReadReq");
44static const std::string WriteReqString("WriteReq");
45static const std::string WriteReqNoAckString("WriteReqNoAck");
46static const std::string ReadRespString("ReadResp");
47static const std::string WriteRespString("WriteResp");
48static const std::string OtherCmdString("<other>");
49
50const std::string &
51Packet::cmdString() const
52{
53    switch (cmd) {
54      case ReadReq:         return ReadReqString;
55      case WriteReq:        return WriteReqString;
56      case WriteReqNoAck:   return WriteReqNoAckString;
57      case ReadResp:        return ReadRespString;
58      case WriteResp:       return WriteRespString;
59      default:              return OtherCmdString;
60    }
61}
62
63const std::string &
64Packet::cmdIdxToString(Packet::Command idx)
65{
66    switch (idx) {
67      case ReadReq:         return ReadReqString;
68      case WriteReq:        return WriteReqString;
69      case WriteReqNoAck:   return WriteReqNoAckString;
70      case ReadResp:        return ReadRespString;
71      case WriteResp:       return WriteRespString;
72      default:              return OtherCmdString;
73    }
74}
75
76/** delete the data pointed to in the data pointer. Ok to call to matter how
77 * data was allocted. */
78void
79Packet::deleteData()
80{
81    assert(staticData || dynamicData);
82    if (staticData)
83        return;
84
85    if (arrayData)
86        delete [] data;
87    else
88        delete data;
89}
90
91/** If there isn't data in the packet, allocate some. */
92void
93Packet::allocate()
94{
95    if (data)
96        return;
97    assert(!staticData);
98    dynamicData = true;
99    arrayData = true;
100    data = new uint8_t[getSize()];
101}
102
103/** Do the packet modify the same addresses. */
104bool
105Packet::intersect(Packet *p)
106{
107    Addr s1 = getAddr();
108    Addr e1 = getAddr() + getSize() - 1;
109    Addr s2 = p->getAddr();
110    Addr e2 = p->getAddr() + p->getSize() - 1;
111
112    return !(s1 > e2 || e1 < s2);
113}
114
115bool
116fixPacket(Packet *func, Packet *timing)
117{
118    Addr funcStart      = func->getAddr();
119    Addr funcEnd        = func->getAddr() + func->getSize() - 1;
120    Addr timingStart    = timing->getAddr();
121    Addr timingEnd      = timing->getAddr() + timing->getSize() - 1;
122
123    assert(!(funcStart > timingEnd || timingStart < funcEnd));
124
125    if (DTRACE(FunctionalAccess)) {
126       DebugOut() << func;
127       DebugOut() << timing;
128    }
129
130    // this packet can't solve our problem, continue on
131    if (!timing->hasData())
132        return true;
133
134    if (func->isRead()) {
135        if (funcStart >= timingStart && funcEnd <= timingEnd) {
136            func->allocate();
137            memcpy(func->getPtr<uint8_t>(), timing->getPtr<uint8_t>() +
138                    funcStart - timingStart, func->getSize());
139            func->result = Packet::Success;
140            return false;
141        } else {
142            // In this case the timing packet only partially satisfies the
143            // requset, so we would need more information to make this work.
144            // Like bytes valid in the packet or something, so the request could
145            // continue and get this bit of possibly newer data along with the
146            // older data not written to yet.
147            panic("Timing packet only partially satisfies the functional"
148                    "request. Now what?");
149        }
150    } else if (func->isWrite()) {
151        if (funcStart >= timingStart) {
152            memcpy(timing->getPtr<uint8_t>() + (funcStart - timingStart),
153                   func->getPtr<uint8_t>(),
154                   funcStart - std::min(funcEnd, timingEnd));
155        } else { // timingStart > funcStart
156            memcpy(timing->getPtr<uint8_t>(),
157                   func->getPtr<uint8_t>() + (timingStart - funcStart),
158                   timingStart - std::min(funcEnd, timingEnd));
159        }
160        // we always want to keep going with a write
161        return true;
162    } else
163        panic("Don't know how to handle command type %#x\n",
164                func->cmdToIndex());
165
166}
167
168
169std::ostream &
170operator<<(std::ostream &o, const Packet &p)
171{
172
173    o << "[0x";
174    o.setf(std::ios_base::hex, std::ios_base::showbase);
175    o <<  p.getAddr();
176    o.unsetf(std::ios_base::hex| std::ios_base::showbase);
177    o <<  ":";
178    o.setf(std::ios_base::hex, std::ios_base::showbase);
179    o <<  p.getAddr() + p.getSize() - 1 << "] ";
180    o.unsetf(std::ios_base::hex| std::ios_base::showbase);
181
182    if (p.result == Packet::Success)
183        o << "Successful ";
184    if (p.result == Packet::BadAddress)
185        o << "BadAddress ";
186    if (p.result == Packet::Nacked)
187        o << "Nacked ";
188    if (p.result == Packet::Unknown)
189        o << "Inflight ";
190
191    if (p.isRead())
192        o << "Read ";
193    if (p.isWrite())
194        o << "Read ";
195    if (p.isInvalidate())
196        o << "Read ";
197    if (p.isRequest())
198        o << "Request ";
199    if (p.isResponse())
200        o << "Response ";
201    if (p.hasData())
202        o << "w/Data ";
203
204    o << std::endl;
205    return o;
206}
207
208