dma_device.cc revision 4762
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 * Nathan Binkert 30 */ 31 32#include "base/chunk_generator.hh" 33#include "base/trace.hh" 34#include "dev/io_device.hh" 35#include "sim/system.hh" 36 37 38PioPort::PioPort(PioDevice *dev, System *s, std::string pname) 39 : SimpleTimingPort(dev->name() + pname, dev), device(dev) 40{ } 41 42 43Tick 44PioPort::recvAtomic(PacketPtr pkt) 45{ 46 return pkt->isRead() ? device->read(pkt) : device->write(pkt); 47} 48 49void 50PioPort::getDeviceAddressRanges(AddrRangeList &resp, bool &snoop) 51{ 52 snoop = false; 53 device->addressRanges(resp); 54} 55 56 57PioDevice::PioDevice(const Params *p) 58 : MemObject(p), platform(p->platform), sys(p->system), pioPort(NULL) 59{} 60 61PioDevice::~PioDevice() 62{ 63 if (pioPort) 64 delete pioPort; 65} 66 67void 68PioDevice::init() 69{ 70 if (!pioPort) 71 panic("Pio port not connected to anything!"); 72 pioPort->sendStatusChange(Port::RangeChange); 73} 74 75 76unsigned int 77PioDevice::drain(Event *de) 78{ 79 unsigned int count; 80 count = pioPort->drain(de); 81 if (count) 82 changeState(Draining); 83 else 84 changeState(Drained); 85 return count; 86} 87 88BasicPioDevice::BasicPioDevice(const Params *p) 89 : PioDevice(p), pioAddr(p->pio_addr), pioSize(0), 90 pioDelay(p->pio_latency) 91{} 92 93void 94BasicPioDevice::addressRanges(AddrRangeList &range_list) 95{ 96 assert(pioSize != 0); 97 range_list.clear(); 98 range_list.push_back(RangeSize(pioAddr, pioSize)); 99} 100 101 102DmaPort::DmaPort(DmaDevice *dev, System *s) 103 : Port(dev->name() + "-dmaport", dev), device(dev), sys(s), 104 pendingCount(0), actionInProgress(0), drainEvent(NULL), 105 backoffTime(0), inRetry(false), backoffEvent(this) 106{ } 107 108bool 109DmaPort::recvTiming(PacketPtr pkt) 110{ 111 112 113 if (pkt->result == Packet::Nacked) { 114 DPRINTF(DMA, "Received nacked %s addr %#x\n", 115 pkt->cmdString(), pkt->getAddr()); 116 117 if (backoffTime < device->minBackoffDelay) 118 backoffTime = device->minBackoffDelay; 119 else if (backoffTime < device->maxBackoffDelay) 120 backoffTime <<= 1; 121 122 backoffEvent.reschedule(curTick + backoffTime, true); 123 124 DPRINTF(DMA, "Backoff time set to %d ticks\n", backoffTime); 125 126 pkt->reinitNacked(); 127 queueDma(pkt, true); 128 } else if (pkt->senderState) { 129 DmaReqState *state; 130 backoffTime >>= 2; 131 132 DPRINTF(DMA, "Received response %s addr %#x size %#x\n", 133 pkt->cmdString(), pkt->getAddr(), pkt->req->getSize()); 134 state = dynamic_cast<DmaReqState*>(pkt->senderState); 135 pendingCount--; 136 137 assert(pendingCount >= 0); 138 assert(state); 139 140 state->numBytes += pkt->req->getSize(); 141 assert(state->totBytes >= state->numBytes); 142 if (state->totBytes == state->numBytes) { 143 state->completionEvent->process(); 144 delete state; 145 } 146 delete pkt->req; 147 delete pkt; 148 149 if (pendingCount == 0 && drainEvent) { 150 drainEvent->process(); 151 drainEvent = NULL; 152 } 153 } else { 154 panic("Got packet without sender state... huh?\n"); 155 } 156 157 return true; 158} 159 160DmaDevice::DmaDevice(const Params *p) 161 : PioDevice(p), dmaPort(NULL), minBackoffDelay(p->min_backoff_delay), 162 maxBackoffDelay(p->max_backoff_delay) 163{ } 164 165 166unsigned int 167DmaDevice::drain(Event *de) 168{ 169 unsigned int count; 170 count = pioPort->drain(de) + dmaPort->drain(de); 171 if (count) 172 changeState(Draining); 173 else 174 changeState(Drained); 175 return count; 176} 177 178unsigned int 179DmaPort::drain(Event *de) 180{ 181 if (pendingCount == 0) 182 return 0; 183 drainEvent = de; 184 return 1; 185} 186 187 188void 189DmaPort::recvRetry() 190{ 191 assert(transmitList.size()); 192 PacketPtr pkt = transmitList.front(); 193 bool result = true; 194 do { 195 DPRINTF(DMA, "Retry on %s addr %#x\n", 196 pkt->cmdString(), pkt->getAddr()); 197 result = sendTiming(pkt); 198 if (result) { 199 DPRINTF(DMA, "-- Done\n"); 200 transmitList.pop_front(); 201 inRetry = false; 202 } else { 203 inRetry = true; 204 DPRINTF(DMA, "-- Failed, queued\n"); 205 } 206 } while (!backoffTime && result && transmitList.size()); 207 208 if (transmitList.size() && backoffTime && !inRetry) { 209 DPRINTF(DMA, "Scheduling backoff for %d\n", curTick+backoffTime); 210 if (!backoffEvent.scheduled()) 211 backoffEvent.schedule(backoffTime+curTick); 212 } 213 DPRINTF(DMA, "TransmitList: %d, backoffTime: %d inRetry: %d es: %d\n", 214 transmitList.size(), backoffTime, inRetry, 215 backoffEvent.scheduled()); 216} 217 218 219void 220DmaPort::dmaAction(Packet::Command cmd, Addr addr, int size, Event *event, 221 uint8_t *data) 222{ 223 assert(event); 224 225 assert(device->getState() == SimObject::Running); 226 227 DmaReqState *reqState = new DmaReqState(event, this, size); 228 229 230 DPRINTF(DMA, "Starting DMA for addr: %#x size: %d sched: %d\n", addr, size, 231 event->scheduled()); 232 for (ChunkGenerator gen(addr, size, peerBlockSize()); 233 !gen.done(); gen.next()) { 234 Request *req = new Request(gen.addr(), gen.size(), 0); 235 PacketPtr pkt = new Packet(req, cmd, Packet::Broadcast); 236 237 // Increment the data pointer on a write 238 if (data) 239 pkt->dataStatic(data + gen.complete()); 240 241 pkt->senderState = reqState; 242 243 assert(pendingCount >= 0); 244 pendingCount++; 245 DPRINTF(DMA, "--Queuing DMA for addr: %#x size: %d\n", gen.addr(), 246 gen.size()); 247 queueDma(pkt); 248 } 249 250} 251 252void 253DmaPort::queueDma(PacketPtr pkt, bool front) 254{ 255 256 if (front) 257 transmitList.push_front(pkt); 258 else 259 transmitList.push_back(pkt); 260 sendDma(); 261} 262 263 264void 265DmaPort::sendDma() 266{ 267 // some kind of selction between access methods 268 // more work is going to have to be done to make 269 // switching actually work 270 assert(transmitList.size()); 271 PacketPtr pkt = transmitList.front(); 272 273 Enums::MemoryMode state = sys->getMemoryMode(); 274 if (state == Enums::timing) { 275 if (backoffEvent.scheduled() || inRetry) { 276 DPRINTF(DMA, "Can't send immediately, waiting for retry or backoff timer\n"); 277 return; 278 } 279 280 DPRINTF(DMA, "Attempting to send %s addr %#x\n", 281 pkt->cmdString(), pkt->getAddr()); 282 283 bool result; 284 do { 285 result = sendTiming(pkt); 286 if (result) { 287 transmitList.pop_front(); 288 DPRINTF(DMA, "-- Done\n"); 289 } else { 290 inRetry = true; 291 DPRINTF(DMA, "-- Failed: queued\n"); 292 } 293 } while (result && !backoffTime && transmitList.size()); 294 295 if (transmitList.size() && backoffTime && !inRetry && 296 !backoffEvent.scheduled()) { 297 DPRINTF(DMA, "-- Scheduling backoff timer for %d\n", 298 backoffTime+curTick); 299 backoffEvent.schedule(backoffTime+curTick); 300 } 301 } else if (state == Enums::atomic) { 302 transmitList.pop_front(); 303 304 Tick lat; 305 DPRINTF(DMA, "--Sending DMA for addr: %#x size: %d\n", 306 pkt->req->getPaddr(), pkt->req->getSize()); 307 lat = sendAtomic(pkt); 308 assert(pkt->senderState); 309 DmaReqState *state = dynamic_cast<DmaReqState*>(pkt->senderState); 310 assert(state); 311 state->numBytes += pkt->req->getSize(); 312 313 DPRINTF(DMA, "--Received response for DMA for addr: %#x size: %d nb: %d, tot: %d sched %d\n", 314 pkt->req->getPaddr(), pkt->req->getSize(), state->numBytes, 315 state->totBytes, state->completionEvent->scheduled()); 316 317 if (state->totBytes == state->numBytes) { 318 assert(!state->completionEvent->scheduled()); 319 state->completionEvent->schedule(curTick + lat); 320 delete state; 321 delete pkt->req; 322 } 323 pendingCount--; 324 assert(pendingCount >= 0); 325 delete pkt; 326 327 if (pendingCount == 0 && drainEvent) { 328 drainEvent->process(); 329 drainEvent = NULL; 330 } 331 332 } else 333 panic("Unknown memory command state."); 334} 335 336DmaDevice::~DmaDevice() 337{ 338 if (dmaPort) 339 delete dmaPort; 340} 341