io_device.hh revision 2846
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 void resendNacked(Packet *pkt); 86 87 /** 88 * This class is used to implemented sendTiming() with a delay. When a delay 89 * is requested a new event is created. When the event time expires it 90 * attempts to send the packet. If it cannot, the packet is pushed onto the 91 * transmit list to be sent when recvRetry() is called. */ 92 class SendEvent : public Event 93 { 94 PioPort *port; 95 Packet *packet; 96 97 SendEvent(PioPort *p, Packet *pkt, Tick t) 98 : Event(&mainEventQueue), port(p), packet(pkt) 99 { schedule(curTick + t); } 100 101 virtual void process(); 102 103 virtual const char *description() 104 { return "Future scheduled sendTiming event"; } 105 106 friend class PioPort; 107 }; 108 109 /** Schedule a sendTiming() event to be called in the future. */ 110 void sendTiming(Packet *pkt, Tick time) 111 { new PioPort::SendEvent(this, pkt, time); } 112 113 /** This function is notification that the device should attempt to send a 114 * packet again. */ 115 virtual void recvRetry(); 116 117 public: 118 PioPort(PioDevice *dev, Platform *p, std::string pname = "-pioport"); 119 120 friend class PioPort::SendEvent; 121}; 122 123 124class DmaPort : public Port 125{ 126 protected: 127 struct DmaReqState : public Packet::SenderState 128 { 129 /** Event to call on the device when this transaction (all packets) 130 * complete. */ 131 Event *completionEvent; 132 133 /** Where we came from for some sanity checking. */ 134 Port *outPort; 135 136 /** Total number of bytes that this transaction involves. */ 137 Addr totBytes; 138 139 /** Number of bytes that have been acked for this transaction. */ 140 Addr numBytes; 141 142 DmaReqState(Event *ce, Port *p, Addr tb) 143 : completionEvent(ce), outPort(p), totBytes(tb), numBytes(0) 144 {} 145 }; 146 147 DmaDevice *device; 148 std::list<Packet*> transmitList; 149 150 /** The platform that device/port are in. This is used to select which mode 151 * we are currently operating in. */ 152 Platform *platform; 153 154 /** Number of outstanding packets the dma port has. */ 155 int pendingCount; 156 157 virtual bool recvTiming(Packet *pkt); 158 virtual Tick recvAtomic(Packet *pkt) 159 { panic("dma port shouldn't be used for pio access."); } 160 virtual void recvFunctional(Packet *pkt) 161 { panic("dma port shouldn't be used for pio access."); } 162 163 virtual void recvStatusChange(Status status) 164 { ; } 165 166 virtual void recvRetry() ; 167 168 virtual void getDeviceAddressRanges(AddrRangeList &resp, AddrRangeList &snoop) 169 { resp.clear(); snoop.clear(); } 170 171 void sendDma(Packet *pkt, bool front = false); 172 173 public: 174 DmaPort(DmaDevice *dev, Platform *p); 175 176 void dmaAction(Packet::Command cmd, Addr addr, int size, Event *event, 177 uint8_t *data = NULL); 178 179 bool dmaPending() { return pendingCount > 0; } 180 181}; 182 183/** 184 * This device is the base class which all devices senstive to an address range 185 * inherit from. There are three pure virtual functions which all devices must 186 * implement addressRanges(), read(), and write(). The magic do choose which 187 * mode we are in, etc is handled by the PioPort so the device doesn't have to 188 * bother. 189 */ 190 191class PioDevice : public MemObject 192{ 193 protected: 194 195 /** The platform we are in. This is used to decide what type of memory 196 * transaction we should perform. */ 197 Platform *platform; 198 199 /** The pioPort that handles the requests for us and provides us requests 200 * that it sees. */ 201 PioPort *pioPort; 202 203 virtual void addressRanges(AddrRangeList &range_list) = 0; 204 205 /** As far as the devices are concerned they only accept atomic transactions 206 * which are converted to either a write or a read. */ 207 Tick recvAtomic(Packet *pkt) 208 { return pkt->isRead() ? this->read(pkt) : this->write(pkt); } 209 210 /** Pure virtual function that the device must implement. Called when a read 211 * command is recieved by the port. 212 * @param pkt Packet describing this request 213 * @return number of ticks it took to complete 214 */ 215 virtual Tick read(Packet *pkt) = 0; 216 217 /** Pure virtual function that the device must implement. Called when a 218 * write command is recieved by the port. 219 * @param pkt Packet describing this request 220 * @return number of ticks it took to complete 221 */ 222 virtual Tick write(Packet *pkt) = 0; 223 224 public: 225 /** Params struct which is extended through each device based on the 226 * parameters it needs. Since we are re-writing everything, we might as well 227 * start from the bottom this time. */ 228 229 struct Params 230 { 231 std::string name; 232 Platform *platform; 233 System *system; 234 }; 235 236 protected: 237 Params *_params; 238 239 public: 240 const Params *params() const { return _params; } 241 242 PioDevice(Params *p) 243 : MemObject(p->name), platform(p->platform), pioPort(NULL), 244 _params(p) 245 {} 246 247 virtual ~PioDevice(); 248 249 virtual void init(); 250 251 virtual Port *getPort(const std::string &if_name, int idx = -1) 252 { 253 if (if_name == "pio") { 254 if (pioPort != NULL) 255 panic("pio port already connected to."); 256 pioPort = new PioPort(this, params()->platform); 257 return pioPort; 258 } else 259 return NULL; 260 } 261 friend class PioPort; 262 263}; 264 265class BasicPioDevice : public PioDevice 266{ 267 public: 268 struct Params : public PioDevice::Params 269 { 270 Addr pio_addr; 271 Tick pio_delay; 272 }; 273 274 protected: 275 /** Address that the device listens to. */ 276 Addr pioAddr; 277 278 /** Size that the device's address range. */ 279 Addr pioSize; 280 281 /** Delay that the device experinces on an access. */ 282 Tick pioDelay; 283 284 public: 285 BasicPioDevice(Params *p) 286 : PioDevice(p), pioAddr(p->pio_addr), pioSize(0), pioDelay(p->pio_delay) 287 {} 288 289 /** return the address ranges that this device responds to. 290 * @params range_list range list to populate with ranges 291 */ 292 void addressRanges(AddrRangeList &range_list); 293 294}; 295 296class DmaDevice : public PioDevice 297{ 298 protected: 299 DmaPort *dmaPort; 300 301 public: 302 DmaDevice(Params *p); 303 virtual ~DmaDevice(); 304 305 void dmaWrite(Addr addr, int size, Event *event, uint8_t *data) 306 { dmaPort->dmaAction(Packet::WriteReq, addr, size, event, data) ; } 307 308 void dmaRead(Addr addr, int size, Event *event, uint8_t *data = NULL) 309 { dmaPort->dmaAction(Packet::ReadReq, addr, size, event, data); } 310 311 bool dmaPending() { return dmaPort->dmaPending(); } 312 313 virtual Port *getPort(const std::string &if_name, int idx = -1) 314 { 315 if (if_name == "pio") { 316 if (pioPort != NULL) 317 panic("pio port already connected to."); 318 pioPort = new PioPort(this, params()->platform); 319 return pioPort; 320 } else if (if_name == "dma") { 321 if (dmaPort != NULL) 322 panic("dma port already connected to."); 323 dmaPort = new DmaPort(this, params()->platform); 324 return dmaPort; 325 } else 326 return NULL; 327 } 328 329 friend class DmaPort; 330}; 331 332 333#endif // __DEV_IO_DEVICE_HH__ 334