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Diffstat (limited to 'mem/port.hh')
| -rw-r--r-- | mem/port.hh | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/mem/port.hh b/mem/port.hh new file mode 100644 index 000000000..9d0bd7968 --- /dev/null +++ b/mem/port.hh @@ -0,0 +1,227 @@ +/* + * 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. + */ + +/** + * @file + * Port Object Decleration. Ports are used to interface memory objects to + * each other. They will always come in pairs, and we refer to the other + * port object as the peer. These are used to make the design more + * modular so that a specific interface between every type of objcet doesn't + * have to be created. + */ + +#ifndef __MEM_PORT_HH__ +#define __MEM_PORT_HH__ + +#include <string> +#include <list> +#include <inttypes.h> + +#include "base/range.hh" +#include "mem/packet.hh" +#include "mem/request.hh" + +/** This typedef is used to clean up the parameter list of + * getDeviceAddressRanges() and getPeerAddressRanges(). It's declared + * outside the Port object since it's also used by some mem objects. + * Eventually we should move this typedef to wherever Addr is + * defined. + */ + +typedef std::list<Range<Addr> > AddrRangeList; + +/** + * Ports are used to interface memory objects to + * each other. They will always come in pairs, and we refer to the other + * port object as the peer. These are used to make the design more + * modular so that a specific interface between every type of objcet doesn't + * have to be created. + * + * Recv accesor functions are being called from the peer interface. + * Send accessor functions are being called from the device the port is + * associated with, and it will call the peer recv. accessor function. + */ +class Port +{ + public: + + // mey be better to use subclasses & RTTI? + /** Holds the ports status. Keeps track if it is blocked, or has + calculated a range change. */ + enum Status { + Blocked, + Unblocked, + RangeChange + }; + + private: + + /** A pointer to the peer port. Ports always come in pairs, that way they + can use a standardized interface to communicate between different + memory objects. */ + Port *peer; + + public: + + /** Function to set the pointer for the peer port. + @todo should be called by the configuration stuff (python). + */ + void setPeer(Port *port) { peer = port; } + + /** Function to set the pointer for the peer port. + @todo should be called by the configuration stuff (python). + */ + Port *getPeer() { return peer; } + + protected: + + /** These functions are protected because they should only be + * called by a peer port, never directly by any outside object. */ + + /** Called to recive a timing call from the peer port. */ + virtual bool recvTiming(Packet &pkt) = 0; + + /** Called to recive a atomic call from the peer port. */ + virtual Tick recvAtomic(Packet &pkt) = 0; + + /** Called to recive a functional call from the peer port. */ + virtual void recvFunctional(Packet &pkt) = 0; + + /** Called to recieve a status change from the peer port. */ + virtual void recvStatusChange(Status status) = 0; + + /** Called by a peer port if the send was unsuccesful, and had to + wait. This shouldn't be valid for response paths (IO Devices). + so it is set to panic if it isn't already defined. + */ + virtual Packet *recvRetry() { panic("??"); } + + /** Called by a peer port in order to determine the block size of the + device connected to this port. It sometimes doesn't make sense for + this function to be called, a DMA interface doesn't really have a + block size, so it is defaulted to a panic. + */ + virtual int deviceBlockSize() { panic("??"); } + + /** The peer port is requesting us to reply with a list of the ranges we + are responsible for. + @param owner is an output param that, if set, indicates that the + port is the owner of the specified ranges (i.e., slave, default + responder, etc.). If 'owner' is false, the interface is + interested in the specified ranges for snooping purposes. If + an object wants to own some ranges and snoop on others, it will + need to use two different ports. + */ + virtual void getDeviceAddressRanges(AddrRangeList &range_list, + bool &owner) + { panic("??"); } + + public: + + /** Function called by associated memory device (cache, memory, iodevice) + in order to send a timing request to the port. Simply calls the peer + port receive function. + @return This function returns if the send was succesful in it's + recieve. If it was a failure, then the port will wait for a recvRetry + at which point it can issue a successful sendTiming. This is used in + case a cache has a higher priority request come in while waiting for + the bus to arbitrate. + */ + bool sendTiming(Packet &pkt) { return peer->recvTiming(pkt); } + + /** Function called by the associated device to send an atomic access, + an access in which the data is moved and the state is updated in one + cycle, without interleaving with other memory accesses. + */ + Tick sendAtomic(Packet &pkt) + { return peer->recvAtomic(pkt); } + + /** Function called by the associated device to send a functional access, + an access in which the data is instantly updated everywhere in the + memory system, without affecting the current state of any block + or moving the block. + */ + void sendFunctional(Packet &pkt) + { return peer->recvFunctional(pkt); } + + /** Called by the associated device to send a status change to the device + connected to the peer interface. + */ + void sendStatusChange(Status status) {peer->recvStatusChange(status); } + + /** When a timing access doesn't return a success, some time later the + Retry will be sent. + */ + Packet *sendRetry() { return peer->recvRetry(); } + + /** Called by the associated device if it wishes to find out the blocksize + of the device on attached to the peer port. + */ + int peerBlockSize() { return peer->deviceBlockSize(); } + + /** Called by the associated device if it wishes to find out the address + ranges connected to the peer ports devices. + */ + void getPeerAddressRanges(AddrRangeList &range_list, bool &owner) + { peer->getDeviceAddressRanges(range_list, owner); } + + // Do we need similar wrappers for sendAtomic()? If not, should + // we drop the "Functional" from the names? + + /** This function is a wrapper around sendFunctional() + that breaks a larger, arbitrarily aligned access into + appropriate chunks. The default implementation can use + getBlockSize() to determine the block size and go from there. + */ + void readBlobFunctional(Addr addr, uint8_t *p, int size); + + /** This function is a wrapper around sendFunctional() + that breaks a larger, arbitrarily aligned access into + appropriate chunks. The default implementation can use + getBlockSize() to determine the block size and go from there. + */ + void writeBlobFunctional(Addr addr, uint8_t *p, int size); + + /** Fill size bytes starting at addr with byte value val. This + should not need to be virtual, since it can be implemented in + terms of writeBlobFunctional(). However, it shouldn't be + performance-critical either, so it could be if we wanted to. + Not even sure if this is actually needed anywhere (there's a + prot_memset on the old functional memory that's never used), + but Nate claims it is. + */ + void memsetBlobFunctional(Addr addr, uint8_t val, int size); + + private: + + /** Internal helper function for read/writeBlob(). + */ + void blobHelper(Addr addr, uint8_t *p, int size, Command cmd); +}; + +#endif //__MEM_PORT_HH__ |