packet.cc revision 4626 
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    /* ReadResp */
60    { SET3(IsRead, IsResponse, HasData), InvalidCmd, "ReadResp" },
61    /* WriteReq */
62    { SET5(IsWrite, NeedsExclusive, IsRequest, NeedsResponse, HasData),
63            WriteResp, "WriteReq" },
64    /* WriteResp */
65    { SET3(IsWrite, NeedsExclusive, IsResponse), InvalidCmd, "WriteResp" },
66    /* Writeback */
67    { SET5(IsWrite, NeedsExclusive, IsRequest, HasData, NeedsResponse),
68            WritebackAck, "Writeback" },
69    /* WritebackAck */
70    { SET3(IsWrite, NeedsExclusive, IsResponse), InvalidCmd, "WritebackAck" },
71    /* SoftPFReq */
72    { SET4(IsRead, IsRequest, IsSWPrefetch, NeedsResponse),
73            SoftPFResp, "SoftPFReq" },
74    /* HardPFReq */
75    { SET4(IsRead, IsRequest, IsHWPrefetch, NeedsResponse),
76            HardPFResp, "HardPFReq" },
77    /* SoftPFResp */
78    { SET4(IsRead, IsResponse, IsSWPrefetch, HasData),
79            InvalidCmd, "SoftPFResp" },
80    /* HardPFResp */
81    { SET4(IsRead, IsResponse, IsHWPrefetch, HasData),
82            InvalidCmd, "HardPFResp" },
83    /* WriteInvalidateReq */
84    { SET6(IsWrite, NeedsExclusive, IsInvalidate,
85           IsRequest, HasData, NeedsResponse),
86            WriteInvalidateResp, "WriteInvalidateReq" },
87    /* WriteInvalidateResp */
88    { SET4(IsWrite, NeedsExclusive, IsInvalidate, IsResponse),
89            InvalidCmd, "WriteInvalidateResp" },
90    /* UpgradeReq */
91    { SET3(IsInvalidate, IsRequest, IsUpgrade), InvalidCmd, "UpgradeReq" },
92    /* ReadExReq */
93    { SET5(IsRead, NeedsExclusive, IsInvalidate, IsRequest, NeedsResponse),
94            ReadExResp, "ReadExReq" },
95    /* ReadExResp */
96    { SET5(IsRead, NeedsExclusive, IsInvalidate, IsResponse, HasData),
97            InvalidCmd, "ReadExResp" },
98    /* LoadLockedReq */
99    { SET4(IsRead, IsLocked, IsRequest, NeedsResponse),
100            ReadResp, "LoadLockedReq" },
101    /* LoadLockedResp */
102    { SET4(IsRead, IsLocked, IsResponse, HasData),
103            InvalidCmd, "LoadLockedResp" },
104    /* StoreCondReq */
105    { SET6(IsWrite, NeedsExclusive, IsLocked,
106           IsRequest, NeedsResponse, HasData),
107            StoreCondResp, "StoreCondReq" },
108    /* StoreCondResp */
109    { SET4(IsWrite, NeedsExclusive, IsLocked, IsResponse),
110            InvalidCmd, "StoreCondResp" },
111    /* SwapReq -- for Swap ldstub type operations */
112    { SET6(IsRead, IsWrite, NeedsExclusive, IsRequest, HasData, NeedsResponse),
113        SwapResp, "SwapReq" },
114    /* SwapResp -- for Swap ldstub type operations */
115    { SET5(IsRead, IsWrite, NeedsExclusive, IsResponse, HasData),
116        InvalidCmd, "SwapResp" }
117};
118
119
120/** delete the data pointed to in the data pointer. Ok to call to matter how
121 * data was allocted. */
122void
123Packet::deleteData()
124{
125    assert(staticData || dynamicData);
126    if (staticData)
127        return;
128
129    if (arrayData)
130        delete [] data;
131    else
132        delete data;
133}
134
135/** If there isn't data in the packet, allocate some. */
136void
137Packet::allocate()
138{
139    if (data)
140        return;
141    assert(!staticData);
142    dynamicData = true;
143    arrayData = true;
144    data = new uint8_t[getSize()];
145}
146
147/** Do the packet modify the same addresses. */
148bool
149Packet::intersect(PacketPtr p)
150{
151    Addr s1 = getAddr();
152    Addr e1 = getAddr() + getSize() - 1;
153    Addr s2 = p->getAddr();
154    Addr e2 = p->getAddr() + p->getSize() - 1;
155
156    return !(s1 > e2 || e1 < s2);
157}
158
159bool
160fixDelayedResponsePacket(PacketPtr func, PacketPtr timing)
161{
162    bool result;
163
164    if (timing->isRead() || timing->isWrite()) {
165        // Ugly hack to deal with the fact that we queue the requests
166        // and don't convert them to responses until we issue them on
167        // the bus.  I tried to avoid this by converting packets to
168        // responses right away, but this breaks during snoops where a
169        // responder may do the conversion before other caches have
170        // done the snoop.  Would work if we copied the packet instead
171        // of just hanging on to a pointer.
172        MemCmd oldCmd = timing->cmd;
173        timing->cmd = timing->cmd.responseCommand();
174        result = fixPacket(func, timing);
175        timing->cmd = oldCmd;
176    }
177    else {
178        //Don't toggle if it isn't a read/write response
179        result = fixPacket(func, timing);
180    }
181
182    return result;
183}
184
185bool
186Packet::checkFunctional(Addr addr, int size, uint8_t *data)
187{
188    Addr func_start = getAddr();
189    Addr func_end   = getAddr() + getSize() - 1;
190    Addr val_start  = addr;
191    Addr val_end    = val_start + size - 1;
192
193    if (func_start > val_end || val_start > func_end) {
194        // no intersection
195        return false;
196    }
197
198    // offset of functional request into supplied value (could be
199    // negative if partial overlap)
200    int offset = func_start - val_start;
201
202    if (isRead()) {
203        if (func_start >= val_start && func_end <= val_end) {
204            allocate();
205            std::memcpy(getPtr<uint8_t>(), data + offset, getSize());
206            result = Packet::Success;
207            return true;
208        } else {
209            // In this case the timing packet only partially satisfies
210            // the request, so we would need more information to make
211            // this work.  Like bytes valid in the packet or
212            // something, so the request could continue and get this
213            // bit of possibly newer data along with the older data
214            // not written to yet.
215            panic("Memory value only partially satisfies the functional "
216                  "request. Now what?");
217        }
218    } else if (isWrite()) {
219        if (offset >= 0) {
220            std::memcpy(data + offset, getPtr<uint8_t>(),
221                        (std::min(func_end, val_end) - func_start) + 1);
222        } else { // val_start > func_start
223            std::memcpy(data, getPtr<uint8_t>() - offset,
224                        (std::min(func_end, val_end) - val_start) + 1);
225        }
226        // we always want to keep going with a write
227        return false;
228    } else
229        panic("Don't know how to handle command %s\n", cmdString());
230}
231
232
233std::ostream &
234operator<<(std::ostream &o, const Packet &p)
235{
236
237    o << "[0x";
238    o.setf(std::ios_base::hex, std::ios_base::showbase);
239    o <<  p.getAddr();
240    o.unsetf(std::ios_base::hex| std::ios_base::showbase);
241    o <<  ":";
242    o.setf(std::ios_base::hex, std::ios_base::showbase);
243    o <<  p.getAddr() + p.getSize() - 1 << "] ";
244    o.unsetf(std::ios_base::hex| std::ios_base::showbase);
245
246    if (p.result == Packet::Success)
247        o << "Successful ";
248    if (p.result == Packet::BadAddress)
249        o << "BadAddress ";
250    if (p.result == Packet::Nacked)
251        o << "Nacked ";
252    if (p.result == Packet::Unknown)
253        o << "Inflight ";
254
255    if (p.isRead())
256        o << "Read ";
257    if (p.isWrite())
258        o << "Write ";
259    if (p.isInvalidate())
260        o << "Invalidate ";
261    if (p.isRequest())
262        o << "Request ";
263    if (p.isResponse())
264        o << "Response ";
265    if (p.hasData())
266        o << "w/Data ";
267
268    o << std::endl;
269    return o;
270}
271
272