1/*
2 * Copyright (c) 2012 ARM Limited
3 * All rights reserved.
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder. You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Copyright (c) 2006 The Regents of The University of Michigan
15 * All rights reserved.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions are
19 * met: redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer;
21 * redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution;
24 * neither the name of the copyright holders nor the names of its
25 * contributors may be used to endorse or promote products derived from
26 * this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 *
40 * Authors: Ali Saidi
41 * Nathan Binkert
42 */
43
44#include "base/chunk_generator.hh"
45#include "debug/DMA.hh"
46#include "debug/Drain.hh"
47#include "dev/dma_device.hh"
48#include "sim/system.hh"
49
50DmaPort::DmaPort(MemObject *dev, System *s, Tick min_backoff, Tick max_backoff)
50DmaPort::DmaPort(MemObject *dev, System *s)
51 : MasterPort(dev->name() + ".dma", dev), device(dev), sys(s),
52 masterId(s->getMasterId(dev->name())),
53 pendingCount(0), drainEvent(NULL),
54 backoffTime(0), minBackoffDelay(min_backoff),
55 maxBackoffDelay(max_backoff), inRetry(false),
56 backoffEvent(this)
54 inRetry(false)
55{ }
56
57bool
58DmaPort::recvTimingResp(PacketPtr pkt)
59{
62 if (pkt->wasNacked()) {
63 DPRINTF(DMA, "Received nacked %s addr %#x\n",
64 pkt->cmdString(), pkt->getAddr());
65
66 if (backoffTime < minBackoffDelay)
67 backoffTime = minBackoffDelay;
68 else if (backoffTime < maxBackoffDelay)
69 backoffTime <<= 1;
70
71 device->reschedule(backoffEvent, curTick() + backoffTime, true);
72
73 DPRINTF(DMA, "Backoff time set to %d ticks\n", backoffTime);
74
75 pkt->reinitNacked();
76 queueDma(pkt, true);
77 } else if (pkt->senderState) {
60 if (pkt->senderState) {
61 DmaReqState *state;
79 backoffTime >>= 2;
62
63 DPRINTF(DMA, "Received response %s addr %#x size %#x\n",
64 pkt->cmdString(), pkt->getAddr(), pkt->req->getSize());
65 state = dynamic_cast<DmaReqState*>(pkt->senderState);
66 pendingCount--;
67
68 assert(pendingCount >= 0);
69 assert(state);
70
71 // We shouldn't ever get a block in ownership state
72 assert(!(pkt->memInhibitAsserted() && !pkt->sharedAsserted()));
73
74 state->numBytes += pkt->req->getSize();
75 assert(state->totBytes >= state->numBytes);
76 if (state->totBytes == state->numBytes) {
77 if (state->completionEvent) {
78 if (state->delay)
79 device->schedule(state->completionEvent,
80 curTick() + state->delay);
81 else
82 state->completionEvent->process();
83 }
84 delete state;
85 }
86 delete pkt->req;
87 delete pkt;
88
89 if (pendingCount == 0 && transmitList.empty() && drainEvent) {
90 drainEvent->process();
91 drainEvent = NULL;
92 }
93 } else {
94 panic("Got packet without sender state... huh?\n");
95 }
96
97 return true;
98}
99
100DmaDevice::DmaDevice(const Params *p)
119 : PioDevice(p), dmaPort(this, sys, params()->min_backoff_delay,
120 params()->max_backoff_delay)
101 : PioDevice(p), dmaPort(this, sys)
102{ }
103
104void
105DmaDevice::init()
106{
107 if (!dmaPort.isConnected())
108 panic("DMA port of %s not connected to anything!", name());
109 PioDevice::init();
110}
111
112unsigned int
113DmaDevice::drain(Event *de)
114{
115 unsigned int count;
116 count = pioPort.drain(de) + dmaPort.drain(de);
117 if (count)
118 changeState(Draining);
119 else
120 changeState(Drained);
121 return count;
122}
123
124unsigned int
125DmaPort::drain(Event *de)
126{
127 if (transmitList.empty() && pendingCount == 0)
128 return 0;
129 drainEvent = de;
130 DPRINTF(Drain, "DmaPort not drained\n");
131 return 1;
132}
133
134void
135DmaPort::recvRetry()
136{
137 assert(transmitList.size());
138 bool result = true;
139 do {
140 PacketPtr pkt = transmitList.front();
141 DPRINTF(DMA, "Retry on %s addr %#x\n",
142 pkt->cmdString(), pkt->getAddr());
143 result = sendTimingReq(pkt);
144 if (result) {
145 DPRINTF(DMA, "-- Done\n");
146 transmitList.pop_front();
147 inRetry = false;
148 } else {
149 inRetry = true;
150 DPRINTF(DMA, "-- Failed, queued\n");
151 }
171 } while (!backoffTime && result && transmitList.size());
152 } while (result && transmitList.size());
153
173 if (transmitList.size() && backoffTime && !inRetry) {
174 DPRINTF(DMA, "Scheduling backoff for %d\n", curTick()+backoffTime);
175 if (!backoffEvent.scheduled())
176 device->schedule(backoffEvent, backoffTime + curTick());
177 }
178 DPRINTF(DMA, "TransmitList: %d, backoffTime: %d inRetry: %d es: %d\n",
179 transmitList.size(), backoffTime, inRetry,
180 backoffEvent.scheduled());
154 DPRINTF(DMA, "TransmitList: %d, inRetry: %d\n",
155 transmitList.size(), inRetry);
156}
157
158void
159DmaPort::dmaAction(Packet::Command cmd, Addr addr, int size, Event *event,
160 uint8_t *data, Tick delay, Request::Flags flag)
161{
162 DmaReqState *reqState = new DmaReqState(event, size, delay);
163
164
165 DPRINTF(DMA, "Starting DMA for addr: %#x size: %d sched: %d\n", addr, size,
166 event ? event->scheduled() : -1 );
167 for (ChunkGenerator gen(addr, size, peerBlockSize());
168 !gen.done(); gen.next()) {
169 Request *req = new Request(gen.addr(), gen.size(), flag, masterId);
170 PacketPtr pkt = new Packet(req, cmd);
171
172 // Increment the data pointer on a write
173 if (data)
174 pkt->dataStatic(data + gen.complete());
175
176 pkt->senderState = reqState;
177
178 assert(pendingCount >= 0);
179 pendingCount++;
180 DPRINTF(DMA, "--Queuing DMA for addr: %#x size: %d\n", gen.addr(),
181 gen.size());
182 queueDma(pkt);
183 }
184
185}
186
187void
188DmaPort::queueDma(PacketPtr pkt, bool front)
189{
190
191 if (front)
192 transmitList.push_front(pkt);
193 else
194 transmitList.push_back(pkt);
195 sendDma();
196}
197
198void
199DmaPort::sendDma()
200{
201 // some kind of selction between access methods
202 // more work is going to have to be done to make
203 // switching actually work
204 assert(transmitList.size());
205 PacketPtr pkt = transmitList.front();
206
207 Enums::MemoryMode state = sys->getMemoryMode();
208 if (state == Enums::timing) {
234 if (backoffEvent.scheduled() || inRetry) {
235 DPRINTF(DMA, "Can't send immediately, waiting for retry or backoff timer\n");
209 if (inRetry) {
210 DPRINTF(DMA, "Can't send immediately, waiting for retry\n");
211 return;
212 }
213
214 DPRINTF(DMA, "Attempting to send %s addr %#x\n",
215 pkt->cmdString(), pkt->getAddr());
216
217 bool result;
218 do {
219 result = sendTimingReq(pkt);
220 if (result) {
221 transmitList.pop_front();
222 DPRINTF(DMA, "-- Done\n");
223 } else {
224 inRetry = true;
225 DPRINTF(DMA, "-- Failed: queued\n");
226 }
252 } while (result && !backoffTime && transmitList.size());
253
254 if (transmitList.size() && backoffTime && !inRetry &&
255 !backoffEvent.scheduled()) {
256 DPRINTF(DMA, "-- Scheduling backoff timer for %d\n",
257 backoffTime+curTick());
258 device->schedule(backoffEvent, backoffTime + curTick());
259 }
227 } while (result && transmitList.size());
228 } else if (state == Enums::atomic) {
229 transmitList.pop_front();
230
231 Tick lat;
232 DPRINTF(DMA, "--Sending DMA for addr: %#x size: %d\n",
233 pkt->req->getPaddr(), pkt->req->getSize());
234 lat = sendAtomic(pkt);
235 assert(pkt->senderState);
236 DmaReqState *state = dynamic_cast<DmaReqState*>(pkt->senderState);
237 assert(state);
238 state->numBytes += pkt->req->getSize();
239
240 DPRINTF(DMA, "--Received response for DMA for addr: %#x size: %d nb: %d, tot: %d sched %d\n",
241 pkt->req->getPaddr(), pkt->req->getSize(), state->numBytes,
242 state->totBytes,
243 state->completionEvent ? state->completionEvent->scheduled() : 0 );
244
245 if (state->totBytes == state->numBytes) {
246 if (state->completionEvent) {
247 assert(!state->completionEvent->scheduled());
248 device->schedule(state->completionEvent,
249 curTick() + lat + state->delay);
250 }
251 delete state;
252 delete pkt->req;
253 }
254 pendingCount--;
255 assert(pendingCount >= 0);
256 delete pkt;
257
258 if (pendingCount == 0 && transmitList.empty() && drainEvent) {
259 DPRINTF(Drain, "DmaPort done draining, processing drain event\n");
260 drainEvent->process();
261 drainEvent = NULL;
262 }
263
264 } else
265 panic("Unknown memory command state.");
266}
267
268DmaDevice::~DmaDevice()
269{
270}
271
272MasterPort &
273DmaDevice::getMasterPort(const std::string &if_name, int idx)
274{
275 if (if_name == "dma") {
276 return dmaPort;
277 }
278 return PioDevice::getMasterPort(if_name, idx);
279}