port.hh revision 5489:94a7bb476fca
1/* 2 * Copyright (c) 2002-2005 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: Ron Dreslinski 29 */ 30 31/** 32 * @file 33 * Port Object Declaration. Ports are used to interface memory objects to 34 * each other. They will always come in pairs, and we refer to the other 35 * port object as the peer. These are used to make the design more 36 * modular so that a specific interface between every type of objcet doesn't 37 * have to be created. 38 */ 39 40#ifndef __MEM_PORT_HH__ 41#define __MEM_PORT_HH__ 42 43#include <list> 44#include <inttypes.h> 45 46#include "base/misc.hh" 47#include "base/range.hh" 48#include "mem/packet.hh" 49#include "mem/request.hh" 50 51/** This typedef is used to clean up the parameter list of 52 * getDeviceAddressRanges() and getPeerAddressRanges(). It's declared 53 * outside the Port object since it's also used by some mem objects. 54 * Eventually we should move this typedef to wherever Addr is 55 * defined. 56 */ 57 58typedef std::list<Range<Addr> > AddrRangeList; 59typedef std::list<Range<Addr> >::iterator AddrRangeIter; 60 61class MemObject; 62 63/** 64 * Ports are used to interface memory objects to 65 * each other. They will always come in pairs, and we refer to the other 66 * port object as the peer. These are used to make the design more 67 * modular so that a specific interface between every type of objcet doesn't 68 * have to be created. 69 * 70 * Recv accesor functions are being called from the peer interface. 71 * Send accessor functions are being called from the device the port is 72 * associated with, and it will call the peer recv. accessor function. 73 */ 74class Port 75{ 76 protected: 77 /** Descriptive name (for DPRINTF output) */ 78 mutable std::string portName; 79 80 /** A pointer to the peer port. Ports always come in pairs, that way they 81 can use a standardized interface to communicate between different 82 memory objects. */ 83 Port *peer; 84 85 /** A pointer to the MemObject that owns this port. This may not be set. */ 86 MemObject *owner; 87 88 public: 89 90 /** 91 * Constructor. 92 * 93 * @param _name Port name for DPRINTF output. Should include name 94 * of memory system object to which the port belongs. 95 * @param _owner Pointer to the MemObject that owns this port. 96 */ 97 Port(const std::string &_name, MemObject *_owner, Port *_peer = NULL); 98 99 /** Return port name (for DPRINTF). */ 100 const std::string &name() const { return portName; } 101 102 virtual ~Port(); 103 104 // mey be better to use subclasses & RTTI? 105 /** Holds the ports status. Currently just that a range recomputation needs 106 * to be done. */ 107 enum Status { 108 RangeChange 109 }; 110 111 /** Function to set the pointer for the peer port. */ 112 virtual void setPeer(Port *port); 113 114 /** Function to get the pointer to the peer port. */ 115 Port *getPeer() { return peer; } 116 117 /** Function to return the owner of this port. */ 118 MemObject *getOwner() { return owner; } 119 120 /** Notify my peer port that I'm disconnecting (by calling its 121 * disconnect() method) so it can clean up. */ 122 void disconnectFromPeer(); 123 124 virtual bool isDefaultPort() const { return false; } 125 126 bool isConnected() { return peer && !peer->isDefaultPort(); } 127 128 protected: 129 130 /** These functions are protected because they should only be 131 * called by a peer port, never directly by any outside object. */ 132 133 /** Called to recive a timing call from the peer port. */ 134 virtual bool recvTiming(PacketPtr pkt) = 0; 135 136 /** Called to recive a atomic call from the peer port. */ 137 virtual Tick recvAtomic(PacketPtr pkt) = 0; 138 139 /** Called to recive a functional call from the peer port. */ 140 virtual void recvFunctional(PacketPtr pkt) = 0; 141 142 /** Called to recieve a status change from the peer port. */ 143 virtual void recvStatusChange(Status status) = 0; 144 145 /** Called by a peer port if the send was unsuccesful, and had to 146 wait. This shouldn't be valid for response paths (IO Devices). 147 so it is set to panic if it isn't already defined. 148 */ 149 virtual void recvRetry() { panic("??"); } 150 151 /** Called by a peer port in order to determine the block size of the 152 device connected to this port. It sometimes doesn't make sense for 153 this function to be called, so it just returns 0. Anytthing that is 154 concerned with the size should just ignore that. 155 */ 156 virtual int deviceBlockSize() { return 0; } 157 158 /** The peer port is requesting us to reply with a list of the ranges we 159 are responsible for. 160 @param resp is a list of ranges responded to 161 @param snoop is a list of ranges snooped 162 */ 163 virtual void getDeviceAddressRanges(AddrRangeList &resp, 164 bool &snoop) 165 { panic("??"); } 166 167 public: 168 169 /** Function called by associated memory device (cache, memory, iodevice) 170 in order to send a timing request to the port. Simply calls the peer 171 port receive function. 172 @return This function returns if the send was succesful in it's 173 recieve. If it was a failure, then the port will wait for a recvRetry 174 at which point it can possibly issue a successful sendTiming. This is used in 175 case a cache has a higher priority request come in while waiting for 176 the bus to arbitrate. 177 */ 178 bool sendTiming(PacketPtr pkt) { return peer->recvTiming(pkt); } 179 180 /** Function called by the associated device to send an atomic 181 * access, an access in which the data is moved and the state is 182 * updated in one cycle, without interleaving with other memory 183 * accesses. Returns estimated latency of access. 184 */ 185 Tick sendAtomic(PacketPtr pkt) 186 { return peer->recvAtomic(pkt); } 187 188 /** Function called by the associated device to send a functional access, 189 an access in which the data is instantly updated everywhere in the 190 memory system, without affecting the current state of any block or 191 moving the block. 192 */ 193 void sendFunctional(PacketPtr pkt) 194 { return peer->recvFunctional(pkt); } 195 196 /** Called by the associated device to send a status change to the device 197 connected to the peer interface. 198 */ 199 void sendStatusChange(Status status) {peer->recvStatusChange(status); } 200 201 /** When a timing access doesn't return a success, some time later the 202 Retry will be sent. 203 */ 204 void sendRetry() { return peer->recvRetry(); } 205 206 /** Called by the associated device if it wishes to find out the blocksize 207 of the device on attached to the peer port. 208 */ 209 int peerBlockSize() { return peer->deviceBlockSize(); } 210 211 /** Called by the associated device if it wishes to find out the address 212 ranges connected to the peer ports devices. 213 */ 214 void getPeerAddressRanges(AddrRangeList &resp, bool &snoop) 215 { peer->getDeviceAddressRanges(resp, snoop); } 216 217 /** This function is a wrapper around sendFunctional() 218 that breaks a larger, arbitrarily aligned access into 219 appropriate chunks. The default implementation can use 220 getBlockSize() to determine the block size and go from there. 221 */ 222 virtual void readBlob(Addr addr, uint8_t *p, int size); 223 224 /** This function is a wrapper around sendFunctional() 225 that breaks a larger, arbitrarily aligned access into 226 appropriate chunks. The default implementation can use 227 getBlockSize() to determine the block size and go from there. 228 */ 229 virtual void writeBlob(Addr addr, uint8_t *p, int size); 230 231 /** Fill size bytes starting at addr with byte value val. This 232 should not need to be virtual, since it can be implemented in 233 terms of writeBlob(). However, it shouldn't be 234 performance-critical either, so it could be if we wanted to. 235 */ 236 virtual void memsetBlob(Addr addr, uint8_t val, int size); 237 238 /** Inject a PrintReq for the given address to print the state of 239 * that address throughout the memory system. For debugging. 240 */ 241 void printAddr(Addr a); 242 243 private: 244 245 /** Internal helper function for read/writeBlob(). 246 */ 247 void blobHelper(Addr addr, uint8_t *p, int size, MemCmd cmd); 248 249 /** Receive notification that my peer is disconnecting and clean 250 * up (potentially deleting myself in the process). Should be 251 * called only from peer's disconnectFromPeer(). */ 252 void disconnect(); 253}; 254 255/** A simple functional port that is only meant for one way communication to 256 * physical memory. It is only meant to be used to load data into memory before 257 * the simulation begins. 258 */ 259 260class FunctionalPort : public Port 261{ 262 public: 263 FunctionalPort(const std::string &_name, MemObject *_owner = NULL) 264 : Port(_name, _owner) 265 {} 266 267 protected: 268 virtual bool recvTiming(PacketPtr pkt) { panic("FuncPort is UniDir"); 269 M5_DUMMY_RETURN } 270 virtual Tick recvAtomic(PacketPtr pkt) { panic("FuncPort is UniDir"); 271 M5_DUMMY_RETURN } 272 virtual void recvFunctional(PacketPtr pkt) { panic("FuncPort is UniDir"); } 273 virtual void recvStatusChange(Status status) {} 274 275 public: 276 /** a write function that also does an endian conversion. */ 277 template <typename T> 278 inline void writeHtoG(Addr addr, T d); 279 280 /** a read function that also does an endian conversion. */ 281 template <typename T> 282 inline T readGtoH(Addr addr); 283 284 template <typename T> 285 inline void write(Addr addr, T d) 286 { 287 writeBlob(addr, (uint8_t*)&d, sizeof(T)); 288 } 289 290 template <typename T> 291 inline T read(Addr addr) 292 { 293 T d; 294 readBlob(addr, (uint8_t*)&d, sizeof(T)); 295 return d; 296 } 297}; 298 299#endif //__MEM_PORT_HH__ 300