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Diffstat (limited to 'src/mem/bus.hh')
| -rw-r--r-- | src/mem/bus.hh | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/src/mem/bus.hh b/src/mem/bus.hh new file mode 100644 index 000000000..941389296 --- /dev/null +++ b/src/mem/bus.hh @@ -0,0 +1,207 @@ +/* + * Copyright (c) 2002-2005 The Regents of The University of Michigan + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Ron Dreslinski + * Ali Saidi + */ + +/** + * @file + * Declaration of a bus object. + */ + +#ifndef __MEM_BUS_HH__ +#define __MEM_BUS_HH__ + +#include <string> +#include <list> +#include <inttypes.h> + +#include "base/range.hh" +#include "mem/mem_object.hh" +#include "mem/packet.hh" +#include "mem/port.hh" +#include "mem/request.hh" + +class Bus : public MemObject +{ + /** a globally unique id for this bus. */ + int busId; + + static const int defaultId = -1; + + struct DevMap { + int portId; + Range<Addr> range; + }; + std::vector<DevMap> portList; + AddrRangeList defaultRange; + std::vector<DevMap> portSnoopList; + + std::vector<int> snoopCallbacks; + + + /** Function called by the port when the bus is recieving a Timing + transaction.*/ + bool recvTiming(Packet *pkt); + + /** Function called by the port when the bus is recieving a Atomic + transaction.*/ + Tick recvAtomic(Packet *pkt); + + /** Function called by the port when the bus is recieving a Functional + transaction.*/ + void recvFunctional(Packet *pkt); + + /** Timing function called by port when it is once again able to process + * requests. */ + void recvRetry(int id); + + /** Function called by the port when the bus is recieving a status change.*/ + void recvStatusChange(Port::Status status, int id); + + /** Find which port connected to this bus (if any) should be given a packet + * with this address. + * @param addr Address to find port for. + * @param id Id of the port this packet was received from (to prevent + * loops) + * @return pointer to port that the packet should be sent out of. + */ + Port *findPort(Addr addr, int id); + + /** Find all ports with a matching snoop range, except src port. Keep in mind + * that the ranges shouldn't overlap or you will get a double snoop to the same + * interface.and the cache will assert out. + * @param addr Address to find snoop prts for. + * @param id Id of the src port of the request to avoid calling snoop on src + * @return vector of IDs to snoop on + */ + std::vector<int> findSnoopPorts(Addr addr, int id); + + /** Snoop all relevant ports atomicly. */ + void atomicSnoop(Packet *pkt); + + /** Snoop for NACK and Blocked in phase 1 + * @return True if succeds. + */ + bool timingSnoopPhase1(Packet *pkt); + + /** @todo Don't need to commit all snoops just those that need it + *(register somehow). */ + /** Commit all snoops now that we know if any of them would have blocked. + */ + void timingSnoopPhase2(Packet *pkt); + + /** Process address range request. + * @param resp addresses that we can respond to + * @param snoop addresses that we would like to snoop + * @param id ide of the busport that made the request. + */ + void addressRanges(AddrRangeList &resp, AddrRangeList &snoop, int id); + + + /** Declaration of the buses port type, one will be instantiated for each + of the interfaces connecting to the bus. */ + class BusPort : public Port + { + /** A pointer to the bus to which this port belongs. */ + Bus *bus; + + /** A id to keep track of the intercafe ID this port is connected to. */ + int id; + + public: + + /** Constructor for the BusPort.*/ + BusPort(const std::string &_name, Bus *_bus, int _id) + : Port(_name), bus(_bus), id(_id) + { } + + protected: + + /** When reciving a timing request from the peer port (at id), + pass it to the bus. */ + virtual bool recvTiming(Packet *pkt) + { pkt->setSrc(id); return bus->recvTiming(pkt); } + + /** When reciving a Atomic requestfrom the peer port (at id), + pass it to the bus. */ + virtual Tick recvAtomic(Packet *pkt) + { pkt->setSrc(id); return bus->recvAtomic(pkt); } + + /** When reciving a Functional requestfrom the peer port (at id), + pass it to the bus. */ + virtual void recvFunctional(Packet *pkt) + { pkt->setSrc(id); bus->recvFunctional(pkt); } + + /** When reciving a status changefrom the peer port (at id), + pass it to the bus. */ + virtual void recvStatusChange(Status status) + { bus->recvStatusChange(status, id); } + + /** When reciving a retry from the peer port (at id), + pass it to the bus. */ + virtual void recvRetry() + { bus->recvRetry(id); } + + // This should return all the 'owned' addresses that are + // downstream from this bus, yes? That is, the union of all + // the 'owned' address ranges of all the other interfaces on + // this bus... + virtual void getDeviceAddressRanges(AddrRangeList &resp, + AddrRangeList &snoop) + { bus->addressRanges(resp, snoop, id); } + + // Hack to make translating port work without changes + virtual int deviceBlockSize() { return 32; } + + }; + + /** An array of pointers to the peer port interfaces + connected to this bus.*/ + std::vector<Port*> interfaces; + + /** An array of pointers to ports that retry should be called on because the + * original send failed for whatever reason.*/ + std::list<Port*> retryList; + + /** Port that handles requests that don't match any of the interfaces.*/ + Port *defaultPort; + + public: + + /** A function used to return the port associated with this bus object. */ + virtual Port *getPort(const std::string &if_name, int idx = -1); + + virtual void init(); + + Bus(const std::string &n, int bus_id) + : MemObject(n), busId(bus_id), defaultPort(NULL) {} + +}; + +#endif //__MEM_BUS_HH__ |