packet.cc revision 4489:381fcb5b6c31 
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 <cstring>
40#include "base/misc.hh"
41#include "base/trace.hh"
42#include "mem/packet.hh"
43
44// The one downside to bitsets is that static initializers can get ugly.
45#define SET1(a1)                     (1 << (a1))
46#define SET2(a1, a2)                 (SET1(a1) | SET1(a2))
47#define SET3(a1, a2, a3)             (SET2(a1, a2) | SET1(a3))
48#define SET4(a1, a2, a3, a4)         (SET3(a1, a2, a3) | SET1(a4))
49#define SET5(a1, a2, a3, a4, a5)     (SET4(a1, a2, a3, a4) | SET1(a5))
50#define SET6(a1, a2, a3, a4, a5, a6) (SET5(a1, a2, a3, a4, a5) | SET1(a6))
51
52const MemCmd::CommandInfo
53MemCmd::commandInfo[] =
54{
55    /* InvalidCmd */
56    { 0, InvalidCmd, "InvalidCmd" },
57    /* ReadReq */
58    { SET3(IsRead, IsRequest, NeedsResponse), ReadResp, "ReadReq" },
59    /* WriteReq */
60    { SET4(IsWrite, IsRequest, NeedsResponse, HasData),
61            WriteResp, "WriteReq" },
62    /* WriteReqNoAck */
63    { SET3(IsWrite, IsRequest, HasData), InvalidCmd, "WriteReqNoAck" },
64    /* ReadResp */
65    { SET3(IsRead, IsResponse, HasData), InvalidCmd, "ReadResp" },
66    /* WriteResp */
67    { SET2(IsWrite, IsResponse), InvalidCmd, "WriteResp" },
68    /* Writeback */
69    { SET3(IsWrite, IsRequest, HasData), InvalidCmd, "Writeback" },
70    /* SoftPFReq */
71    { SET4(IsRead, IsRequest, IsSWPrefetch, NeedsResponse),
72            SoftPFResp, "SoftPFReq" },
73    /* HardPFReq */
74    { SET4(IsRead, IsRequest, IsHWPrefetch, NeedsResponse),
75            HardPFResp, "HardPFReq" },
76    /* SoftPFResp */
77    { SET4(IsRead, IsResponse, IsSWPrefetch, HasData),
78            InvalidCmd, "SoftPFResp" },
79    /* HardPFResp */
80    { SET4(IsRead, IsResponse, IsHWPrefetch, HasData),
81            InvalidCmd, "HardPFResp" },
82    /* InvalidateReq */
83    { SET2(IsInvalidate, IsRequest), InvalidCmd, "InvalidateReq" },
84    /* WriteInvalidateReq */
85    { SET5(IsWrite, IsInvalidate, IsRequest, HasData, NeedsResponse),
86            WriteInvalidateResp, "WriteInvalidateReq" },
87    /* WriteInvalidateResp */
88    { SET3(IsWrite, IsInvalidate, IsResponse),
89            InvalidCmd, "WriteInvalidateResp" },
90    /* UpgradeReq */
91    { SET3(IsInvalidate, IsRequest, IsUpgrade), InvalidCmd, "UpgradeReq" },
92    /* ReadExReq */
93    { SET4(IsRead, IsInvalidate, IsRequest, NeedsResponse),
94            ReadExResp, "ReadExReq" },
95    /* ReadExResp */
96    { SET4(IsRead, IsInvalidate, IsResponse, HasData),
97            InvalidCmd, "ReadExResp" },
98    /* SwapReq -- for Swap ldstub type operations */
99    { SET4(IsReadWrite, IsRequest, HasData, NeedsResponse),
100        SwapResp, "SwapReq" },
101    /* SwapResp -- for Swap ldstub type operations */
102    { SET3(IsReadWrite, IsResponse, HasData),
103        InvalidCmd, "SwapResp" }
104};
105
106
107/** delete the data pointed to in the data pointer. Ok to call to matter how
108 * data was allocted. */
109void
110Packet::deleteData()
111{
112    assert(staticData || dynamicData);
113    if (staticData)
114        return;
115
116    if (arrayData)
117        delete [] data;
118    else
119        delete data;
120}
121
122/** If there isn't data in the packet, allocate some. */
123void
124Packet::allocate()
125{
126    if (data)
127        return;
128    assert(!staticData);
129    dynamicData = true;
130    arrayData = true;
131    data = new uint8_t[getSize()];
132}
133
134/** Do the packet modify the same addresses. */
135bool
136Packet::intersect(PacketPtr p)
137{
138    Addr s1 = getAddr();
139    Addr e1 = getAddr() + getSize() - 1;
140    Addr s2 = p->getAddr();
141    Addr e2 = p->getAddr() + p->getSize() - 1;
142
143    return !(s1 > e2 || e1 < s2);
144}
145
146bool
147fixDelayedResponsePacket(PacketPtr func, PacketPtr timing)
148{
149    bool result;
150
151    if (timing->isRead() || timing->isWrite()) {
152        // Ugly hack to deal with the fact that we queue the requests
153        // and don't convert them to responses until we issue them on
154        // the bus.  I tried to avoid this by converting packets to
155        // responses right away, but this breaks during snoops where a
156        // responder may do the conversion before other caches have
157        // done the snoop.  Would work if we copied the packet instead
158        // of just hanging on to a pointer.
159        MemCmd oldCmd = timing->cmd;
160        timing->cmd = timing->cmd.responseCommand();
161        result = fixPacket(func, timing);
162        timing->cmd = oldCmd;
163    }
164    else {
165        //Don't toggle if it isn't a read/write response
166        result = fixPacket(func, timing);
167    }
168
169    return result;
170}
171
172bool
173fixPacket(PacketPtr func, PacketPtr timing)
174{
175    Addr funcStart      = func->getAddr();
176    Addr funcEnd        = func->getAddr() + func->getSize() - 1;
177    Addr timingStart    = timing->getAddr();
178    Addr timingEnd      = timing->getAddr() + timing->getSize() - 1;
179
180    assert(!(funcStart > timingEnd || timingStart > funcEnd));
181
182    // this packet can't solve our problem, continue on
183    if (!timing->hasData())
184        return true;
185
186    if (func->isRead()) {
187        if (funcStart >= timingStart && funcEnd <= timingEnd) {
188            func->allocate();
189            std::memcpy(func->getPtr<uint8_t>(), timing->getPtr<uint8_t>() +
190                    funcStart - timingStart, func->getSize());
191            func->result = Packet::Success;
192            func->flags |= SATISFIED;
193            return false;
194        } else {
195            // In this case the timing packet only partially satisfies
196            // the request, so we would need more information to make
197            // this work.  Like bytes valid in the packet or
198            // something, so the request could continue and get this
199            // bit of possibly newer data along with the older data
200            // not written to yet.
201            panic("Timing packet only partially satisfies the functional"
202                    "request. Now what?");
203        }
204    } else if (func->isWrite()) {
205        if (funcStart >= timingStart) {
206            std::memcpy(timing->getPtr<uint8_t>() + (funcStart - timingStart),
207                   func->getPtr<uint8_t>(),
208                   (std::min(funcEnd, timingEnd) - funcStart) + 1);
209        } else { // timingStart > funcStart
210            std::memcpy(timing->getPtr<uint8_t>(),
211                   func->getPtr<uint8_t>() + (timingStart - funcStart),
212                   (std::min(funcEnd, timingEnd) - timingStart) + 1);
213        }
214        // we always want to keep going with a write
215        return true;
216    } else
217        panic("Don't know how to handle command type %#x\n",
218                func->cmdToIndex());
219
220}
221
222
223std::ostream &
224operator<<(std::ostream &o, const Packet &p)
225{
226
227    o << "[0x";
228    o.setf(std::ios_base::hex, std::ios_base::showbase);
229    o <<  p.getAddr();
230    o.unsetf(std::ios_base::hex| std::ios_base::showbase);
231    o <<  ":";
232    o.setf(std::ios_base::hex, std::ios_base::showbase);
233    o <<  p.getAddr() + p.getSize() - 1 << "] ";
234    o.unsetf(std::ios_base::hex| std::ios_base::showbase);
235
236    if (p.result == Packet::Success)
237        o << "Successful ";
238    if (p.result == Packet::BadAddress)
239        o << "BadAddress ";
240    if (p.result == Packet::Nacked)
241        o << "Nacked ";
242    if (p.result == Packet::Unknown)
243        o << "Inflight ";
244
245    if (p.isRead())
246        o << "Read ";
247    if (p.isWrite())
248        o << "Write ";
249    if (p.isReadWrite())
250        o << "Read/Write ";
251    if (p.isInvalidate())
252        o << "Invalidate ";
253    if (p.isRequest())
254        o << "Request ";
255    if (p.isResponse())
256        o << "Response ";
257    if (p.hasData())
258        o << "w/Data ";
259
260    o << std::endl;
261    return o;
262}
263
264