port.hh revision 5476:758c2413765a
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 Port(); 91 92 /** 93 * Constructor. 94 * 95 * @param _name Port name for DPRINTF output. Should include name 96 * of memory system object to which the port belongs. 97 * @param _owner Pointer to the MemObject that owns this port. 98 * Will not necessarily be set. 99 */ 100 Port(const std::string &_name, MemObject *_owner = NULL); 101 102 /** Return port name (for DPRINTF). */ 103 const std::string &name() const { return portName; } 104 105 virtual ~Port(); 106 107 // mey be better to use subclasses & RTTI? 108 /** Holds the ports status. Currently just that a range recomputation needs 109 * to be done. */ 110 enum Status { 111 RangeChange 112 }; 113 114 void setName(const std::string &name) 115 { portName = name; } 116 117 /** Function to set the pointer for the peer port. */ 118 virtual void setPeer(Port *port); 119 120 /** Function to get the pointer to the peer port. */ 121 Port *getPeer() { return peer; } 122 123 /** Function to set the owner of this port. */ 124 void setOwner(MemObject *_owner) { owner = _owner; } 125 126 /** Function to return the owner of this port. */ 127 MemObject *getOwner() { return owner; } 128 129 /** Inform the peer port to delete itself and notify it's owner about it's 130 * demise. */ 131 void removeConn(); 132 133 virtual bool isDefaultPort() const { return false; } 134 135 bool isConnected() { return peer && !peer->isDefaultPort(); } 136 137 protected: 138 139 /** These functions are protected because they should only be 140 * called by a peer port, never directly by any outside object. */ 141 142 /** Called to recive a timing call from the peer port. */ 143 virtual bool recvTiming(PacketPtr pkt) = 0; 144 145 /** Called to recive a atomic call from the peer port. */ 146 virtual Tick recvAtomic(PacketPtr pkt) = 0; 147 148 /** Called to recive a functional call from the peer port. */ 149 virtual void recvFunctional(PacketPtr pkt) = 0; 150 151 /** Called to recieve a status change from the peer port. */ 152 virtual void recvStatusChange(Status status) = 0; 153 154 /** Called by a peer port if the send was unsuccesful, and had to 155 wait. This shouldn't be valid for response paths (IO Devices). 156 so it is set to panic if it isn't already defined. 157 */ 158 virtual void recvRetry() { panic("??"); } 159 160 /** Called by a peer port in order to determine the block size of the 161 device connected to this port. It sometimes doesn't make sense for 162 this function to be called, so it just returns 0. Anytthing that is 163 concerned with the size should just ignore that. 164 */ 165 virtual int deviceBlockSize() { return 0; } 166 167 /** The peer port is requesting us to reply with a list of the ranges we 168 are responsible for. 169 @param resp is a list of ranges responded to 170 @param snoop is a list of ranges snooped 171 */ 172 virtual void getDeviceAddressRanges(AddrRangeList &resp, 173 bool &snoop) 174 { panic("??"); } 175 176 public: 177 178 /** Function called by associated memory device (cache, memory, iodevice) 179 in order to send a timing request to the port. Simply calls the peer 180 port receive function. 181 @return This function returns if the send was succesful in it's 182 recieve. If it was a failure, then the port will wait for a recvRetry 183 at which point it can possibly issue a successful sendTiming. This is used in 184 case a cache has a higher priority request come in while waiting for 185 the bus to arbitrate. 186 */ 187 bool sendTiming(PacketPtr pkt) { return peer->recvTiming(pkt); } 188 189 /** Function called by the associated device to send an atomic 190 * access, an access in which the data is moved and the state is 191 * updated in one cycle, without interleaving with other memory 192 * accesses. Returns estimated latency of access. 193 */ 194 Tick sendAtomic(PacketPtr pkt) 195 { return peer->recvAtomic(pkt); } 196 197 /** Function called by the associated device to send a functional access, 198 an access in which the data is instantly updated everywhere in the 199 memory system, without affecting the current state of any block or 200 moving the block. 201 */ 202 void sendFunctional(PacketPtr pkt) 203 { return peer->recvFunctional(pkt); } 204 205 /** Called by the associated device to send a status change to the device 206 connected to the peer interface. 207 */ 208 void sendStatusChange(Status status) {peer->recvStatusChange(status); } 209 210 /** When a timing access doesn't return a success, some time later the 211 Retry will be sent. 212 */ 213 void sendRetry() { return peer->recvRetry(); } 214 215 /** Called by the associated device if it wishes to find out the blocksize 216 of the device on attached to the peer port. 217 */ 218 int peerBlockSize() { return peer->deviceBlockSize(); } 219 220 /** Called by the associated device if it wishes to find out the address 221 ranges connected to the peer ports devices. 222 */ 223 void getPeerAddressRanges(AddrRangeList &resp, bool &snoop) 224 { peer->getDeviceAddressRanges(resp, snoop); } 225 226 /** This function is a wrapper around sendFunctional() 227 that breaks a larger, arbitrarily aligned access into 228 appropriate chunks. The default implementation can use 229 getBlockSize() to determine the block size and go from there. 230 */ 231 virtual void readBlob(Addr addr, uint8_t *p, int size); 232 233 /** This function is a wrapper around sendFunctional() 234 that breaks a larger, arbitrarily aligned access into 235 appropriate chunks. The default implementation can use 236 getBlockSize() to determine the block size and go from there. 237 */ 238 virtual void writeBlob(Addr addr, uint8_t *p, int size); 239 240 /** Fill size bytes starting at addr with byte value val. This 241 should not need to be virtual, since it can be implemented in 242 terms of writeBlob(). However, it shouldn't be 243 performance-critical either, so it could be if we wanted to. 244 */ 245 virtual void memsetBlob(Addr addr, uint8_t val, int size); 246 247 /** Inject a PrintReq for the given address to print the state of 248 * that address throughout the memory system. For debugging. 249 */ 250 void printAddr(Addr a); 251 252 private: 253 254 /** Internal helper function for read/writeBlob(). 255 */ 256 void blobHelper(Addr addr, uint8_t *p, int size, MemCmd cmd); 257}; 258 259/** A simple functional port that is only meant for one way communication to 260 * physical memory. It is only meant to be used to load data into memory before 261 * the simulation begins. 262 */ 263 264class FunctionalPort : public Port 265{ 266 public: 267 FunctionalPort(const std::string &_name, MemObject *_owner = NULL) 268 : Port(_name, _owner) 269 {} 270 271 protected: 272 virtual bool recvTiming(PacketPtr pkt) { panic("FuncPort is UniDir"); 273 M5_DUMMY_RETURN } 274 virtual Tick recvAtomic(PacketPtr pkt) { panic("FuncPort is UniDir"); 275 M5_DUMMY_RETURN } 276 virtual void recvFunctional(PacketPtr pkt) { panic("FuncPort is UniDir"); } 277 virtual void recvStatusChange(Status status) {} 278 279 public: 280 /** a write function that also does an endian conversion. */ 281 template <typename T> 282 inline void writeHtoG(Addr addr, T d); 283 284 /** a read function that also does an endian conversion. */ 285 template <typename T> 286 inline T readGtoH(Addr addr); 287 288 template <typename T> 289 inline void write(Addr addr, T d) 290 { 291 writeBlob(addr, (uint8_t*)&d, sizeof(T)); 292 } 293 294 template <typename T> 295 inline T read(Addr addr) 296 { 297 T d; 298 readBlob(addr, (uint8_t*)&d, sizeof(T)); 299 return d; 300 } 301}; 302 303#endif //__MEM_PORT_HH__ 304