io_device.cc revision 8948:e95ee70f876c 
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                 bool recv_snoops)
125    : MasterPort(dev->name() + "-dmaport", dev), device(dev), sys(s),
126      masterId(s->getMasterId(dev->name())),
127      pendingCount(0), actionInProgress(0), drainEvent(NULL),
128      backoffTime(0), minBackoffDelay(min_backoff),
129      maxBackoffDelay(max_backoff), inRetry(false), recvSnoops(recv_snoops),
130      backoffEvent(this)
131{ }
132
133bool
134DmaPort::recvTiming(PacketPtr pkt)
135{
136    assert(pkt->isResponse());
137    if (pkt->wasNacked()) {
138        DPRINTF(DMA, "Received nacked %s addr %#x\n",
139                pkt->cmdString(), pkt->getAddr());
140
141        if (backoffTime < minBackoffDelay)
142            backoffTime = minBackoffDelay;
143        else if (backoffTime < maxBackoffDelay)
144            backoffTime <<= 1;
145
146        device->reschedule(backoffEvent, curTick() + backoffTime, true);
147
148        DPRINTF(DMA, "Backoff time set to %d ticks\n", backoffTime);
149
150        pkt->reinitNacked();
151        queueDma(pkt, true);
152    } else if (pkt->senderState) {
153        DmaReqState *state;
154        backoffTime >>= 2;
155
156        DPRINTF(DMA, "Received response %s addr %#x size %#x\n",
157                pkt->cmdString(), pkt->getAddr(), pkt->req->getSize());
158        state = dynamic_cast<DmaReqState*>(pkt->senderState);
159        pendingCount--;
160
161        assert(pendingCount >= 0);
162        assert(state);
163
164        // We shouldn't ever get a block in ownership state
165        assert(!(pkt->memInhibitAsserted() && !pkt->sharedAsserted()));
166
167        state->numBytes += pkt->req->getSize();
168        assert(state->totBytes >= state->numBytes);
169        if (state->totBytes == state->numBytes) {
170            if (state->completionEvent) {
171                if (state->delay)
172                    device->schedule(state->completionEvent,
173                                     curTick() + state->delay);
174                else
175                    state->completionEvent->process();
176            }
177            delete state;
178        }
179        delete pkt->req;
180        delete pkt;
181
182        if (pendingCount == 0 && drainEvent) {
183            drainEvent->process();
184            drainEvent = NULL;
185        }
186    }  else {
187        panic("Got packet without sender state... huh?\n");
188    }
189
190    return true;
191}
192
193DmaDevice::DmaDevice(const Params *p)
194    : PioDevice(p), dmaPort(this, sys, params()->min_backoff_delay,
195                            params()->max_backoff_delay)
196{ }
197
198void
199DmaDevice::init()
200{
201    if (!dmaPort.isConnected())
202        panic("DMA port of %s not connected to anything!", name());
203    PioDevice::init();
204}
205
206unsigned int
207DmaDevice::drain(Event *de)
208{
209    unsigned int count;
210    count = pioPort.drain(de) + dmaPort.drain(de);
211    if (count)
212        changeState(Draining);
213    else
214        changeState(Drained);
215    return count;
216}
217
218unsigned int
219DmaPort::drain(Event *de)
220{
221    if (pendingCount == 0)
222        return 0;
223    drainEvent = de;
224    return 1;
225}
226
227
228void
229DmaPort::recvRetry()
230{
231    assert(transmitList.size());
232    bool result = true;
233    do {
234        PacketPtr pkt = transmitList.front();
235        DPRINTF(DMA, "Retry on %s addr %#x\n",
236                pkt->cmdString(), pkt->getAddr());
237        result = sendTiming(pkt);
238        if (result) {
239            DPRINTF(DMA, "-- Done\n");
240            transmitList.pop_front();
241            inRetry = false;
242        } else {
243            inRetry = true;
244            DPRINTF(DMA, "-- Failed, queued\n");
245        }
246    } while (!backoffTime &&  result && transmitList.size());
247
248    if (transmitList.size() && backoffTime && !inRetry) {
249        DPRINTF(DMA, "Scheduling backoff for %d\n", curTick()+backoffTime);
250        if (!backoffEvent.scheduled())
251            device->schedule(backoffEvent, backoffTime + curTick());
252    }
253    DPRINTF(DMA, "TransmitList: %d, backoffTime: %d inRetry: %d es: %d\n",
254            transmitList.size(), backoffTime, inRetry,
255            backoffEvent.scheduled());
256}
257
258
259void
260DmaPort::dmaAction(Packet::Command cmd, Addr addr, int size, Event *event,
261                   uint8_t *data, Tick delay, Request::Flags flag)
262{
263    assert(device->getState() == SimObject::Running);
264
265    DmaReqState *reqState = new DmaReqState(event, this, size, delay);
266
267
268    DPRINTF(DMA, "Starting DMA for addr: %#x size: %d sched: %d\n", addr, size,
269            event ? event->scheduled() : -1 );
270    for (ChunkGenerator gen(addr, size, peerBlockSize());
271         !gen.done(); gen.next()) {
272            Request *req = new Request(gen.addr(), gen.size(), flag, masterId);
273            PacketPtr pkt = new Packet(req, cmd, Packet::Broadcast);
274
275            // Increment the data pointer on a write
276            if (data)
277                pkt->dataStatic(data + gen.complete());
278
279            pkt->senderState = reqState;
280
281            assert(pendingCount >= 0);
282            pendingCount++;
283            DPRINTF(DMA, "--Queuing DMA for addr: %#x size: %d\n", gen.addr(),
284                    gen.size());
285            queueDma(pkt);
286    }
287
288}
289
290void
291DmaPort::queueDma(PacketPtr pkt, bool front)
292{
293
294    if (front)
295        transmitList.push_front(pkt);
296    else
297        transmitList.push_back(pkt);
298    sendDma();
299}
300
301
302void
303DmaPort::sendDma()
304{
305    // some kind of selction between access methods
306    // more work is going to have to be done to make
307    // switching actually work
308    assert(transmitList.size());
309    PacketPtr pkt = transmitList.front();
310
311    Enums::MemoryMode state = sys->getMemoryMode();
312    if (state == Enums::timing) {
313        if (backoffEvent.scheduled() || inRetry) {
314            DPRINTF(DMA, "Can't send immediately, waiting for retry or backoff timer\n");
315            return;
316        }
317
318        DPRINTF(DMA, "Attempting to send %s addr %#x\n",
319                pkt->cmdString(), pkt->getAddr());
320
321        bool result;
322        do {
323            result = sendTiming(pkt);
324            if (result) {
325                transmitList.pop_front();
326                DPRINTF(DMA, "-- Done\n");
327            } else {
328                inRetry = true;
329                DPRINTF(DMA, "-- Failed: queued\n");
330            }
331        } while (result && !backoffTime && transmitList.size());
332
333        if (transmitList.size() && backoffTime && !inRetry &&
334                !backoffEvent.scheduled()) {
335            DPRINTF(DMA, "-- Scheduling backoff timer for %d\n",
336                    backoffTime+curTick());
337            device->schedule(backoffEvent, backoffTime + curTick());
338        }
339    } else if (state == Enums::atomic) {
340        transmitList.pop_front();
341
342        Tick lat;
343        DPRINTF(DMA, "--Sending  DMA for addr: %#x size: %d\n",
344                pkt->req->getPaddr(), pkt->req->getSize());
345        lat = sendAtomic(pkt);
346        assert(pkt->senderState);
347        DmaReqState *state = dynamic_cast<DmaReqState*>(pkt->senderState);
348        assert(state);
349        state->numBytes += pkt->req->getSize();
350
351        DPRINTF(DMA, "--Received response for  DMA for addr: %#x size: %d nb: %d, tot: %d sched %d\n",
352                pkt->req->getPaddr(), pkt->req->getSize(), state->numBytes,
353                state->totBytes,
354                state->completionEvent ? state->completionEvent->scheduled() : 0 );
355
356        if (state->totBytes == state->numBytes) {
357            if (state->completionEvent) {
358                assert(!state->completionEvent->scheduled());
359                device->schedule(state->completionEvent,
360                                 curTick() + lat + state->delay);
361            }
362            delete state;
363            delete pkt->req;
364        }
365        pendingCount--;
366        assert(pendingCount >= 0);
367        delete pkt;
368
369        if (pendingCount == 0 && drainEvent) {
370            drainEvent->process();
371            drainEvent = NULL;
372        }
373
374   } else
375       panic("Unknown memory command state.");
376}
377
378DmaDevice::~DmaDevice()
379{
380}
381
382
383MasterPort &
384DmaDevice::getMasterPort(const std::string &if_name, int idx)
385{
386    if (if_name == "dma") {
387        return dmaPort;
388    }
389    return PioDevice::getMasterPort(if_name, idx);
390}
391
392