dma_device.cc revision 9015 
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 "base/trace.hh"
46#include "debug/BusAddrRanges.hh"
47#include "debug/DMA.hh"
48#include "dev/io_device.hh"
49#include "sim/system.hh"
50
51PioPort::PioPort(PioDevice *dev)
52    : SimpleTimingPort(dev->name() + "-pioport", dev), device(dev)
53{
54}
55
56
57Tick
58PioPort::recvAtomic(PacketPtr pkt)
59{
60    return pkt->isRead() ? device->read(pkt) : device->write(pkt);
61}
62
63AddrRangeList
64PioPort::getAddrRanges()
65{
66    return device->getAddrRanges();
67}
68
69
70PioDevice::PioDevice(const Params *p)
71    : MemObject(p), sys(p->system), pioPort(this)
72{}
73
74PioDevice::~PioDevice()
75{
76}
77
78void
79PioDevice::init()
80{
81    if (!pioPort.isConnected())
82        panic("Pio port of %s not connected to anything!", name());
83    pioPort.sendRangeChange();
84}
85
86SlavePort &
87PioDevice::getSlavePort(const std::string &if_name, int idx)
88{
89    if (if_name == "pio") {
90        return pioPort;
91    }
92    return MemObject::getSlavePort(if_name, idx);
93}
94
95unsigned int
96PioDevice::drain(Event *de)
97{
98    unsigned int count;
99    count = pioPort.drain(de);
100    if (count)
101        changeState(Draining);
102    else
103        changeState(Drained);
104    return count;
105}
106
107BasicPioDevice::BasicPioDevice(const Params *p)
108    : PioDevice(p), pioAddr(p->pio_addr), pioSize(0),
109      pioDelay(p->pio_latency)
110{}
111
112AddrRangeList
113BasicPioDevice::getAddrRanges()
114{
115    assert(pioSize != 0);
116    AddrRangeList ranges;
117    DPRINTF(BusAddrRanges, "registering range: %#x-%#x\n", pioAddr, pioSize);
118    ranges.push_back(RangeSize(pioAddr, pioSize));
119    return ranges;
120}
121
122
123DmaPort::DmaPort(MemObject *dev, System *s, Tick min_backoff, Tick max_backoff)
124    : MasterPort(dev->name() + "-dma", dev), device(dev), sys(s),
125      masterId(s->getMasterId(dev->name())),
126      pendingCount(0), actionInProgress(0), drainEvent(NULL),
127      backoffTime(0), minBackoffDelay(min_backoff),
128      maxBackoffDelay(max_backoff), inRetry(false),
129      backoffEvent(this)
130{ }
131
132bool
133DmaPort::recvTimingResp(PacketPtr pkt)
134{
135    if (pkt->wasNacked()) {
136        DPRINTF(DMA, "Received nacked %s addr %#x\n",
137                pkt->cmdString(), pkt->getAddr());
138
139        if (backoffTime < minBackoffDelay)
140            backoffTime = minBackoffDelay;
141        else if (backoffTime < maxBackoffDelay)
142            backoffTime <<= 1;
143
144        device->reschedule(backoffEvent, curTick() + backoffTime, true);
145
146        DPRINTF(DMA, "Backoff time set to %d ticks\n", backoffTime);
147
148        pkt->reinitNacked();
149        queueDma(pkt, true);
150    } else if (pkt->senderState) {
151        DmaReqState *state;
152        backoffTime >>= 2;
153
154        DPRINTF(DMA, "Received response %s addr %#x size %#x\n",
155                pkt->cmdString(), pkt->getAddr(), pkt->req->getSize());
156        state = dynamic_cast<DmaReqState*>(pkt->senderState);
157        pendingCount--;
158
159        assert(pendingCount >= 0);
160        assert(state);
161
162        // We shouldn't ever get a block in ownership state
163        assert(!(pkt->memInhibitAsserted() && !pkt->sharedAsserted()));
164
165        state->numBytes += pkt->req->getSize();
166        assert(state->totBytes >= state->numBytes);
167        if (state->totBytes == state->numBytes) {
168            if (state->completionEvent) {
169                if (state->delay)
170                    device->schedule(state->completionEvent,
171                                     curTick() + state->delay);
172                else
173                    state->completionEvent->process();
174            }
175            delete state;
176        }
177        delete pkt->req;
178        delete pkt;
179
180        if (pendingCount == 0 && drainEvent) {
181            drainEvent->process();
182            drainEvent = NULL;
183        }
184    }  else {
185        panic("Got packet without sender state... huh?\n");
186    }
187
188    return true;
189}
190
191DmaDevice::DmaDevice(const Params *p)
192    : PioDevice(p), dmaPort(this, sys, params()->min_backoff_delay,
193                            params()->max_backoff_delay)
194{ }
195
196void
197DmaDevice::init()
198{
199    if (!dmaPort.isConnected())
200        panic("DMA port of %s not connected to anything!", name());
201    PioDevice::init();
202}
203
204unsigned int
205DmaDevice::drain(Event *de)
206{
207    unsigned int count;
208    count = pioPort.drain(de) + dmaPort.drain(de);
209    if (count)
210        changeState(Draining);
211    else
212        changeState(Drained);
213    return count;
214}
215
216unsigned int
217DmaPort::drain(Event *de)
218{
219    if (pendingCount == 0)
220        return 0;
221    drainEvent = de;
222    return 1;
223}
224
225
226void
227DmaPort::recvRetry()
228{
229    assert(transmitList.size());
230    bool result = true;
231    do {
232        PacketPtr pkt = transmitList.front();
233        DPRINTF(DMA, "Retry on %s addr %#x\n",
234                pkt->cmdString(), pkt->getAddr());
235        result = sendTimingReq(pkt);
236        if (result) {
237            DPRINTF(DMA, "-- Done\n");
238            transmitList.pop_front();
239            inRetry = false;
240        } else {
241            inRetry = true;
242            DPRINTF(DMA, "-- Failed, queued\n");
243        }
244    } while (!backoffTime &&  result && transmitList.size());
245
246    if (transmitList.size() && backoffTime && !inRetry) {
247        DPRINTF(DMA, "Scheduling backoff for %d\n", curTick()+backoffTime);
248        if (!backoffEvent.scheduled())
249            device->schedule(backoffEvent, backoffTime + curTick());
250    }
251    DPRINTF(DMA, "TransmitList: %d, backoffTime: %d inRetry: %d es: %d\n",
252            transmitList.size(), backoffTime, inRetry,
253            backoffEvent.scheduled());
254}
255
256
257void
258DmaPort::dmaAction(Packet::Command cmd, Addr addr, int size, Event *event,
259                   uint8_t *data, Tick delay, Request::Flags flag)
260{
261    assert(device->getState() == SimObject::Running);
262
263    DmaReqState *reqState = new DmaReqState(event, this, size, delay);
264
265
266    DPRINTF(DMA, "Starting DMA for addr: %#x size: %d sched: %d\n", addr, size,
267            event ? event->scheduled() : -1 );
268    for (ChunkGenerator gen(addr, size, peerBlockSize());
269         !gen.done(); gen.next()) {
270            Request *req = new Request(gen.addr(), gen.size(), flag, masterId);
271            PacketPtr pkt = new Packet(req, cmd);
272
273            // Increment the data pointer on a write
274            if (data)
275                pkt->dataStatic(data + gen.complete());
276
277            pkt->senderState = reqState;
278
279            assert(pendingCount >= 0);
280            pendingCount++;
281            DPRINTF(DMA, "--Queuing DMA for addr: %#x size: %d\n", gen.addr(),
282                    gen.size());
283            queueDma(pkt);
284    }
285
286}
287
288void
289DmaPort::queueDma(PacketPtr pkt, bool front)
290{
291
292    if (front)
293        transmitList.push_front(pkt);
294    else
295        transmitList.push_back(pkt);
296    sendDma();
297}
298
299
300void
301DmaPort::sendDma()
302{
303    // some kind of selction between access methods
304    // more work is going to have to be done to make
305    // switching actually work
306    assert(transmitList.size());
307    PacketPtr pkt = transmitList.front();
308
309    Enums::MemoryMode state = sys->getMemoryMode();
310    if (state == Enums::timing) {
311        if (backoffEvent.scheduled() || inRetry) {
312            DPRINTF(DMA, "Can't send immediately, waiting for retry or backoff timer\n");
313            return;
314        }
315
316        DPRINTF(DMA, "Attempting to send %s addr %#x\n",
317                pkt->cmdString(), pkt->getAddr());
318
319        bool result;
320        do {
321            result = sendTimingReq(pkt);
322            if (result) {
323                transmitList.pop_front();
324                DPRINTF(DMA, "-- Done\n");
325            } else {
326                inRetry = true;
327                DPRINTF(DMA, "-- Failed: queued\n");
328            }
329        } while (result && !backoffTime && transmitList.size());
330
331        if (transmitList.size() && backoffTime && !inRetry &&
332                !backoffEvent.scheduled()) {
333            DPRINTF(DMA, "-- Scheduling backoff timer for %d\n",
334                    backoffTime+curTick());
335            device->schedule(backoffEvent, backoffTime + curTick());
336        }
337    } else if (state == Enums::atomic) {
338        transmitList.pop_front();
339
340        Tick lat;
341        DPRINTF(DMA, "--Sending  DMA for addr: %#x size: %d\n",
342                pkt->req->getPaddr(), pkt->req->getSize());
343        lat = sendAtomic(pkt);
344        assert(pkt->senderState);
345        DmaReqState *state = dynamic_cast<DmaReqState*>(pkt->senderState);
346        assert(state);
347        state->numBytes += pkt->req->getSize();
348
349        DPRINTF(DMA, "--Received response for  DMA for addr: %#x size: %d nb: %d, tot: %d sched %d\n",
350                pkt->req->getPaddr(), pkt->req->getSize(), state->numBytes,
351                state->totBytes,
352                state->completionEvent ? state->completionEvent->scheduled() : 0 );
353
354        if (state->totBytes == state->numBytes) {
355            if (state->completionEvent) {
356                assert(!state->completionEvent->scheduled());
357                device->schedule(state->completionEvent,
358                                 curTick() + lat + state->delay);
359            }
360            delete state;
361            delete pkt->req;
362        }
363        pendingCount--;
364        assert(pendingCount >= 0);
365        delete pkt;
366
367        if (pendingCount == 0 && drainEvent) {
368            drainEvent->process();
369            drainEvent = NULL;
370        }
371
372   } else
373       panic("Unknown memory command state.");
374}
375
376DmaDevice::~DmaDevice()
377{
378}
379
380
381MasterPort &
382DmaDevice::getMasterPort(const std::string &if_name, int idx)
383{
384    if (if_name == "dma") {
385        return dmaPort;
386    }
387    return PioDevice::getMasterPort(if_name, idx);
388}
389
390