io_device.cc revision 8975:7f36d4436074 
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::recvTimingResp(PacketPtr pkt)
135{
136    if (pkt->wasNacked()) {
137        DPRINTF(DMA, "Received nacked %s addr %#x\n",
138                pkt->cmdString(), pkt->getAddr());
139
140        if (backoffTime < minBackoffDelay)
141            backoffTime = minBackoffDelay;
142        else if (backoffTime < maxBackoffDelay)
143            backoffTime <<= 1;
144
145        device->reschedule(backoffEvent, curTick() + backoffTime, true);
146
147        DPRINTF(DMA, "Backoff time set to %d ticks\n", backoffTime);
148
149        pkt->reinitNacked();
150        queueDma(pkt, true);
151    } else if (pkt->senderState) {
152        DmaReqState *state;
153        backoffTime >>= 2;
154
155        DPRINTF(DMA, "Received response %s addr %#x size %#x\n",
156                pkt->cmdString(), pkt->getAddr(), pkt->req->getSize());
157        state = dynamic_cast<DmaReqState*>(pkt->senderState);
158        pendingCount--;
159
160        assert(pendingCount >= 0);
161        assert(state);
162
163        // We shouldn't ever get a block in ownership state
164        assert(!(pkt->memInhibitAsserted() && !pkt->sharedAsserted()));
165
166        state->numBytes += pkt->req->getSize();
167        assert(state->totBytes >= state->numBytes);
168        if (state->totBytes == state->numBytes) {
169            if (state->completionEvent) {
170                if (state->delay)
171                    device->schedule(state->completionEvent,
172                                     curTick() + state->delay);
173                else
174                    state->completionEvent->process();
175            }
176            delete state;
177        }
178        delete pkt->req;
179        delete pkt;
180
181        if (pendingCount == 0 && drainEvent) {
182            drainEvent->process();
183            drainEvent = NULL;
184        }
185    }  else {
186        panic("Got packet without sender state... huh?\n");
187    }
188
189    return true;
190}
191
192DmaDevice::DmaDevice(const Params *p)
193    : PioDevice(p), dmaPort(this, sys, params()->min_backoff_delay,
194                            params()->max_backoff_delay)
195{ }
196
197void
198DmaDevice::init()
199{
200    if (!dmaPort.isConnected())
201        panic("DMA port of %s not connected to anything!", name());
202    PioDevice::init();
203}
204
205unsigned int
206DmaDevice::drain(Event *de)
207{
208    unsigned int count;
209    count = pioPort.drain(de) + dmaPort.drain(de);
210    if (count)
211        changeState(Draining);
212    else
213        changeState(Drained);
214    return count;
215}
216
217unsigned int
218DmaPort::drain(Event *de)
219{
220    if (pendingCount == 0)
221        return 0;
222    drainEvent = de;
223    return 1;
224}
225
226
227void
228DmaPort::recvRetry()
229{
230    assert(transmitList.size());
231    bool result = true;
232    do {
233        PacketPtr pkt = transmitList.front();
234        DPRINTF(DMA, "Retry on %s addr %#x\n",
235                pkt->cmdString(), pkt->getAddr());
236        result = sendTimingReq(pkt);
237        if (result) {
238            DPRINTF(DMA, "-- Done\n");
239            transmitList.pop_front();
240            inRetry = false;
241        } else {
242            inRetry = true;
243            DPRINTF(DMA, "-- Failed, queued\n");
244        }
245    } while (!backoffTime &&  result && transmitList.size());
246
247    if (transmitList.size() && backoffTime && !inRetry) {
248        DPRINTF(DMA, "Scheduling backoff for %d\n", curTick()+backoffTime);
249        if (!backoffEvent.scheduled())
250            device->schedule(backoffEvent, backoffTime + curTick());
251    }
252    DPRINTF(DMA, "TransmitList: %d, backoffTime: %d inRetry: %d es: %d\n",
253            transmitList.size(), backoffTime, inRetry,
254            backoffEvent.scheduled());
255}
256
257
258void
259DmaPort::dmaAction(Packet::Command cmd, Addr addr, int size, Event *event,
260                   uint8_t *data, Tick delay, Request::Flags flag)
261{
262    assert(device->getState() == SimObject::Running);
263
264    DmaReqState *reqState = new DmaReqState(event, this, size, delay);
265
266
267    DPRINTF(DMA, "Starting DMA for addr: %#x size: %d sched: %d\n", addr, size,
268            event ? event->scheduled() : -1 );
269    for (ChunkGenerator gen(addr, size, peerBlockSize());
270         !gen.done(); gen.next()) {
271            Request *req = new Request(gen.addr(), gen.size(), flag, masterId);
272            PacketPtr pkt = new Packet(req, cmd);
273
274            // Increment the data pointer on a write
275            if (data)
276                pkt->dataStatic(data + gen.complete());
277
278            pkt->senderState = reqState;
279
280            assert(pendingCount >= 0);
281            pendingCount++;
282            DPRINTF(DMA, "--Queuing DMA for addr: %#x size: %d\n", gen.addr(),
283                    gen.size());
284            queueDma(pkt);
285    }
286
287}
288
289void
290DmaPort::queueDma(PacketPtr pkt, bool front)
291{
292
293    if (front)
294        transmitList.push_front(pkt);
295    else
296        transmitList.push_back(pkt);
297    sendDma();
298}
299
300
301void
302DmaPort::sendDma()
303{
304    // some kind of selction between access methods
305    // more work is going to have to be done to make
306    // switching actually work
307    assert(transmitList.size());
308    PacketPtr pkt = transmitList.front();
309
310    Enums::MemoryMode state = sys->getMemoryMode();
311    if (state == Enums::timing) {
312        if (backoffEvent.scheduled() || inRetry) {
313            DPRINTF(DMA, "Can't send immediately, waiting for retry or backoff timer\n");
314            return;
315        }
316
317        DPRINTF(DMA, "Attempting to send %s addr %#x\n",
318                pkt->cmdString(), pkt->getAddr());
319
320        bool result;
321        do {
322            result = sendTimingReq(pkt);
323            if (result) {
324                transmitList.pop_front();
325                DPRINTF(DMA, "-- Done\n");
326            } else {
327                inRetry = true;
328                DPRINTF(DMA, "-- Failed: queued\n");
329            }
330        } while (result && !backoffTime && transmitList.size());
331
332        if (transmitList.size() && backoffTime && !inRetry &&
333                !backoffEvent.scheduled()) {
334            DPRINTF(DMA, "-- Scheduling backoff timer for %d\n",
335                    backoffTime+curTick());
336            device->schedule(backoffEvent, backoffTime + curTick());
337        }
338    } else if (state == Enums::atomic) {
339        transmitList.pop_front();
340
341        Tick lat;
342        DPRINTF(DMA, "--Sending  DMA for addr: %#x size: %d\n",
343                pkt->req->getPaddr(), pkt->req->getSize());
344        lat = sendAtomic(pkt);
345        assert(pkt->senderState);
346        DmaReqState *state = dynamic_cast<DmaReqState*>(pkt->senderState);
347        assert(state);
348        state->numBytes += pkt->req->getSize();
349
350        DPRINTF(DMA, "--Received response for  DMA for addr: %#x size: %d nb: %d, tot: %d sched %d\n",
351                pkt->req->getPaddr(), pkt->req->getSize(), state->numBytes,
352                state->totBytes,
353                state->completionEvent ? state->completionEvent->scheduled() : 0 );
354
355        if (state->totBytes == state->numBytes) {
356            if (state->completionEvent) {
357                assert(!state->completionEvent->scheduled());
358                device->schedule(state->completionEvent,
359                                 curTick() + lat + state->delay);
360            }
361            delete state;
362            delete pkt->req;
363        }
364        pendingCount--;
365        assert(pendingCount >= 0);
366        delete pkt;
367
368        if (pendingCount == 0 && drainEvent) {
369            drainEvent->process();
370            drainEvent = NULL;
371        }
372
373   } else
374       panic("Unknown memory command state.");
375}
376
377DmaDevice::~DmaDevice()
378{
379}
380
381
382MasterPort &
383DmaDevice::getMasterPort(const std::string &if_name, int idx)
384{
385    if (if_name == "dma") {
386        return dmaPort;
387    }
388    return PioDevice::getMasterPort(if_name, idx);
389}
390
391