io_device.hh revision 2685:a0821abe7132
1/* 2 * Copyright (c) 2004-2005 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#ifndef __DEV_IO_DEVICE_HH__ 33#define __DEV_IO_DEVICE_HH__ 34 35#include "base/chunk_generator.hh" 36#include "mem/mem_object.hh" 37#include "mem/packet_impl.hh" 38#include "sim/eventq.hh" 39#include "sim/sim_object.hh" 40 41class Platform; 42class PioDevice; 43class DmaDevice; 44class System; 45 46/** 47 * The PioPort class is a programmed i/o port that all devices that are 48 * sensitive to an address range use. The port takes all the memory 49 * access types and roles them into one read() and write() call that the device 50 * must respond to. The device must also provide the addressRanges() function 51 * with which it returns the address ranges it is interested in. An extra 52 * sendTiming() function is implemented which takes an delay. In this way the 53 * device can immediatly call sendTiming(pkt, time) after processing a request 54 * and the request will be handled by the port even if the port bus the device 55 * connects to is blocked. 56 */ 57class PioPort : public Port 58{ 59 protected: 60 /** The device that this port serves. */ 61 PioDevice *device; 62 63 /** The platform that device/port are in. This is used to select which mode 64 * we are currently operating in. */ 65 Platform *platform; 66 67 /** A list of outgoing timing response packets that haven't been serviced 68 * yet. */ 69 std::list<Packet*> transmitList; 70 71 /** The current status of the peer(bus) that we are connected to. */ 72 Status peerStatus; 73 74 virtual bool recvTiming(Packet *pkt); 75 76 virtual Tick recvAtomic(Packet *pkt); 77 78 virtual void recvFunctional(Packet *pkt) ; 79 80 virtual void recvStatusChange(Status status) 81 { peerStatus = status; } 82 83 virtual void getDeviceAddressRanges(AddrRangeList &resp, AddrRangeList &snoop); 84 85 /** 86 * This class is used to implemented sendTiming() with a delay. When a delay 87 * is requested a new event is created. When the event time expires it 88 * attempts to send the packet. If it cannot, the packet is pushed onto the 89 * transmit list to be sent when recvRetry() is called. */ 90 class SendEvent : public Event 91 { 92 PioPort *port; 93 Packet *packet; 94 95 SendEvent(PioPort *p, Packet *pkt, Tick t) 96 : Event(&mainEventQueue), port(p), packet(pkt) 97 { schedule(curTick + t); } 98 99 virtual void process(); 100 101 virtual const char *description() 102 { return "Future scheduled sendTiming event"; } 103 104 friend class PioPort; 105 }; 106 107 /** Schedule a sendTiming() event to be called in the future. */ 108 void sendTiming(Packet *pkt, Tick time) 109 { new PioPort::SendEvent(this, pkt, time); } 110 111 /** This function is notification that the device should attempt to send a 112 * packet again. */ 113 virtual void recvRetry(); 114 115 public: 116 PioPort(PioDevice *dev, Platform *p); 117 118 friend class PioPort::SendEvent; 119}; 120 121 122struct DmaReqState : public Packet::SenderState 123{ 124 /** Event to call on the device when this transaction (all packets) 125 * complete. */ 126 Event *completionEvent; 127 128 /** Where we came from for some sanity checking. */ 129 Port *outPort; 130 131 /** Total number of bytes that this transaction involves. */ 132 Addr totBytes; 133 134 /** Number of bytes that have been acked for this transaction. */ 135 Addr numBytes; 136 137 bool final; 138 DmaReqState(Event *ce, Port *p, Addr tb) 139 : completionEvent(ce), outPort(p), totBytes(tb), numBytes(0) 140 {} 141}; 142 143class DmaPort : public Port 144{ 145 protected: 146 DmaDevice *device; 147 std::list<Packet*> transmitList; 148 149 /** The platform that device/port are in. This is used to select which mode 150 * we are currently operating in. */ 151 Platform *platform; 152 153 /** Number of outstanding packets the dma port has. */ 154 int pendingCount; 155 156 virtual bool recvTiming(Packet *pkt); 157 virtual Tick recvAtomic(Packet *pkt) 158 { panic("dma port shouldn't be used for pio access."); } 159 virtual void recvFunctional(Packet *pkt) 160 { panic("dma port shouldn't be used for pio access."); } 161 162 virtual void recvStatusChange(Status status) 163 { ; } 164 165 virtual void recvRetry() ; 166 167 virtual void getDeviceAddressRanges(AddrRangeList &resp, AddrRangeList &snoop) 168 { resp.clear(); snoop.clear(); } 169 170 void sendDma(Packet *pkt, bool front = false); 171 172 public: 173 DmaPort(DmaDevice *dev, Platform *p); 174 175 void dmaAction(Packet::Command cmd, Addr addr, int size, Event *event, 176 uint8_t *data = NULL); 177 178 bool dmaPending() { return pendingCount > 0; } 179 180}; 181 182/** 183 * This device is the base class which all devices senstive to an address range 184 * inherit from. There are three pure virtual functions which all devices must 185 * implement addressRanges(), read(), and write(). The magic do choose which 186 * mode we are in, etc is handled by the PioPort so the device doesn't have to 187 * bother. 188 */ 189 190class PioDevice : public MemObject 191{ 192 protected: 193 194 /** The platform we are in. This is used to decide what type of memory 195 * transaction we should perform. */ 196 Platform *platform; 197 198 /** The pioPort that handles the requests for us and provides us requests 199 * that it sees. */ 200 PioPort *pioPort; 201 202 virtual void addressRanges(AddrRangeList &range_list) = 0; 203 204 /** As far as the devices are concerned they only accept atomic transactions 205 * which are converted to either a write or a read. */ 206 Tick recvAtomic(Packet *pkt) 207 { return pkt->isRead() ? this->read(pkt) : this->write(pkt); } 208 209 /** Pure virtual function that the device must implement. Called when a read 210 * command is recieved by the port. 211 * @param pkt Packet describing this request 212 * @return number of ticks it took to complete 213 */ 214 virtual Tick read(Packet *pkt) = 0; 215 216 /** Pure virtual function that the device must implement. Called when a 217 * write command is recieved by the port. 218 * @param pkt Packet describing this request 219 * @return number of ticks it took to complete 220 */ 221 virtual Tick write(Packet *pkt) = 0; 222 223 public: 224 /** Params struct which is extended through each device based on the 225 * parameters it needs. Since we are re-writing everything, we might as well 226 * start from the bottom this time. */ 227 228 struct Params 229 { 230 std::string name; 231 Platform *platform; 232 System *system; 233 }; 234 235 protected: 236 Params *_params; 237 238 public: 239 const Params *params() const { return _params; } 240 241 PioDevice(Params *p) 242 : MemObject(p->name), platform(p->platform), pioPort(NULL), 243 _params(p) 244 {} 245 246 virtual ~PioDevice(); 247 248 virtual void init(); 249 250 virtual Port *getPort(const std::string &if_name) 251 { 252 if (if_name == "pio") { 253 if (pioPort != NULL) 254 panic("pio port already connected to."); 255 pioPort = new PioPort(this, params()->platform); 256 return pioPort; 257 } else 258 return NULL; 259 } 260 friend class PioPort; 261 262}; 263 264class BasicPioDevice : public PioDevice 265{ 266 public: 267 struct Params : public PioDevice::Params 268 { 269 Addr pio_addr; 270 Tick pio_delay; 271 }; 272 273 protected: 274 /** Address that the device listens to. */ 275 Addr pioAddr; 276 277 /** Size that the device's address range. */ 278 Addr pioSize; 279 280 /** Delay that the device experinces on an access. */ 281 Tick pioDelay; 282 283 public: 284 BasicPioDevice(Params *p) 285 : PioDevice(p), pioAddr(p->pio_addr), pioSize(0), pioDelay(p->pio_delay) 286 {} 287 288 /** return the address ranges that this device responds to. 289 * @params range_list range list to populate with ranges 290 */ 291 void addressRanges(AddrRangeList &range_list); 292 293}; 294 295class DmaDevice : public PioDevice 296{ 297 protected: 298 DmaPort *dmaPort; 299 300 public: 301 DmaDevice(Params *p); 302 virtual ~DmaDevice(); 303 304 void dmaWrite(Addr addr, int size, Event *event, uint8_t *data) 305 { dmaPort->dmaAction(Packet::WriteReq, addr, size, event, data) ; } 306 307 void dmaRead(Addr addr, int size, Event *event, uint8_t *data = NULL) 308 { dmaPort->dmaAction(Packet::ReadReq, addr, size, event, data); } 309 310 bool dmaPending() { return dmaPort->dmaPending(); } 311 312 virtual Port *getPort(const std::string &if_name) 313 { 314 if (if_name == "pio") { 315 if (pioPort != NULL) 316 panic("pio port already connected to."); 317 pioPort = new PioPort(this, params()->platform); 318 return pioPort; 319 } else if (if_name == "dma") { 320 if (dmaPort != NULL) 321 panic("dma port already connected to."); 322 dmaPort = new DmaPort(this, params()->platform); 323 return dmaPort; 324 } else 325 return NULL; 326 } 327 328 friend class DmaPort; 329}; 330 331 332#endif // __DEV_IO_DEVICE_HH__ 333