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gem5/src/mem/mport.hh

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Create a message port for sending messages as apposed to reading/writing a memory range.
2008-10-12 21:08:51 +02:00
/*
MEM: Introduce the master/slave port sub-classes in C++ This patch introduces the notion of a master and slave port in the C++ code, thus bringing the previous classification from the Python classes into the corresponding simulation objects and memory objects. The patch enables us to classify behaviours into the two bins and add assumptions and enfore compliance, also simplifying the two interfaces. As a starting point, isSnooping is confined to a master port, and getAddrRanges to slave ports. More of these specilisations are to come in later patches. The getPort function is not getMasterPort and getSlavePort, and returns a port reference rather than a pointer as NULL would never be a valid return value. The default implementation of these two functions is placed in MemObject, and calls fatal. The one drawback with this specific patch is that it requires some code duplication, e.g. QueuedPort becomes QueuedMasterPort and QueuedSlavePort, and BusPort becomes BusMasterPort and BusSlavePort (avoiding multiple inheritance). With the later introduction of the port interfaces, moving the functionality outside the port itself, a lot of the duplicated code will disappear again.
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* Copyright (c) 2012 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
Create a message port for sending messages as apposed to reading/writing a memory range.
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* Copyright (c) 2008 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: Gabe Black
*/
#ifndef __MEM_MPORT_HH__
#define __MEM_MPORT_HH__
MEM: Split SimpleTimingPort into PacketQueue and ports This patch decouples the queueing and the port interactions to simplify the introduction of the master and slave ports. By separating the queueing functionality from the port itself, it becomes much easier to distinguish between master and slave ports, and still retain the queueing ability for both (without code duplication). As part of the split into a PacketQueue and a port, there is now also a hierarchy of two port classes, QueuedPort and SimpleTimingPort. The QueuedPort is useful for ports that want to leave the packet transmission of outgoing packets to the queue and is used by both master and slave ports. The SimpleTimingPort inherits from the QueuedPort and adds the implemention of recvTiming and recvFunctional through recvAtomic. The PioPort and MessagePort are cleaned up as part of the changes. --HG-- rename : src/mem/tport.cc => src/mem/packet_queue.cc rename : src/mem/tport.hh => src/mem/packet_queue.hh
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#include "mem/mem_object.hh"
Create a message port for sending messages as apposed to reading/writing a memory range.
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#include "mem/tport.hh"
/*
* This file defines a port class which is used for sending and receiving
* messages. These messages are atomic units which don't interact and
* should be smaller than a cache block. This class is based on
* the underpinnings of SimpleTimingPort, but it tweaks some of the external
* functions.
*/
MEM: Introduce the master/slave port sub-classes in C++ This patch introduces the notion of a master and slave port in the C++ code, thus bringing the previous classification from the Python classes into the corresponding simulation objects and memory objects. The patch enables us to classify behaviours into the two bins and add assumptions and enfore compliance, also simplifying the two interfaces. As a starting point, isSnooping is confined to a master port, and getAddrRanges to slave ports. More of these specilisations are to come in later patches. The getPort function is not getMasterPort and getSlavePort, and returns a port reference rather than a pointer as NULL would never be a valid return value. The default implementation of these two functions is placed in MemObject, and calls fatal. The one drawback with this specific patch is that it requires some code duplication, e.g. QueuedPort becomes QueuedMasterPort and QueuedSlavePort, and BusPort becomes BusMasterPort and BusSlavePort (avoiding multiple inheritance). With the later introduction of the port interfaces, moving the functionality outside the port itself, a lot of the duplicated code will disappear again.
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class MessageSlavePort : public SimpleTimingPort
Create a message port for sending messages as apposed to reading/writing a memory range.
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{
MEM: Split SimpleTimingPort into PacketQueue and ports This patch decouples the queueing and the port interactions to simplify the introduction of the master and slave ports. By separating the queueing functionality from the port itself, it becomes much easier to distinguish between master and slave ports, and still retain the queueing ability for both (without code duplication). As part of the split into a PacketQueue and a port, there is now also a hierarchy of two port classes, QueuedPort and SimpleTimingPort. The QueuedPort is useful for ports that want to leave the packet transmission of outgoing packets to the queue and is used by both master and slave ports. The SimpleTimingPort inherits from the QueuedPort and adds the implemention of recvTiming and recvFunctional through recvAtomic. The PioPort and MessagePort are cleaned up as part of the changes. --HG-- rename : src/mem/tport.cc => src/mem/packet_queue.cc rename : src/mem/tport.hh => src/mem/packet_queue.hh
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Create a message port for sending messages as apposed to reading/writing a memory range.
2008-10-12 21:08:51 +02:00
public:
MEM: Introduce the master/slave port sub-classes in C++ This patch introduces the notion of a master and slave port in the C++ code, thus bringing the previous classification from the Python classes into the corresponding simulation objects and memory objects. The patch enables us to classify behaviours into the two bins and add assumptions and enfore compliance, also simplifying the two interfaces. As a starting point, isSnooping is confined to a master port, and getAddrRanges to slave ports. More of these specilisations are to come in later patches. The getPort function is not getMasterPort and getSlavePort, and returns a port reference rather than a pointer as NULL would never be a valid return value. The default implementation of these two functions is placed in MemObject, and calls fatal. The one drawback with this specific patch is that it requires some code duplication, e.g. QueuedPort becomes QueuedMasterPort and QueuedSlavePort, and BusPort becomes BusMasterPort and BusSlavePort (avoiding multiple inheritance). With the later introduction of the port interfaces, moving the functionality outside the port itself, a lot of the duplicated code will disappear again.
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MessageSlavePort(const std::string &name, MemObject *owner) :
MEM: Split SimpleTimingPort into PacketQueue and ports This patch decouples the queueing and the port interactions to simplify the introduction of the master and slave ports. By separating the queueing functionality from the port itself, it becomes much easier to distinguish between master and slave ports, and still retain the queueing ability for both (without code duplication). As part of the split into a PacketQueue and a port, there is now also a hierarchy of two port classes, QueuedPort and SimpleTimingPort. The QueuedPort is useful for ports that want to leave the packet transmission of outgoing packets to the queue and is used by both master and slave ports. The SimpleTimingPort inherits from the QueuedPort and adds the implemention of recvTiming and recvFunctional through recvAtomic. The PioPort and MessagePort are cleaned up as part of the changes. --HG-- rename : src/mem/tport.cc => src/mem/packet_queue.cc rename : src/mem/tport.hh => src/mem/packet_queue.hh
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SimpleTimingPort(name, owner)
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{}
MEM: Introduce the master/slave port sub-classes in C++ This patch introduces the notion of a master and slave port in the C++ code, thus bringing the previous classification from the Python classes into the corresponding simulation objects and memory objects. The patch enables us to classify behaviours into the two bins and add assumptions and enfore compliance, also simplifying the two interfaces. As a starting point, isSnooping is confined to a master port, and getAddrRanges to slave ports. More of these specilisations are to come in later patches. The getPort function is not getMasterPort and getSlavePort, and returns a port reference rather than a pointer as NULL would never be a valid return value. The default implementation of these two functions is placed in MemObject, and calls fatal. The one drawback with this specific patch is that it requires some code duplication, e.g. QueuedPort becomes QueuedMasterPort and QueuedSlavePort, and BusPort becomes BusMasterPort and BusSlavePort (avoiding multiple inheritance). With the later introduction of the port interfaces, moving the functionality outside the port itself, a lot of the duplicated code will disappear again.
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virtual ~MessageSlavePort()
Create a message port for sending messages as apposed to reading/writing a memory range.
2008-10-12 21:08:51 +02:00
{}
MEM: Split SimpleTimingPort into PacketQueue and ports This patch decouples the queueing and the port interactions to simplify the introduction of the master and slave ports. By separating the queueing functionality from the port itself, it becomes much easier to distinguish between master and slave ports, and still retain the queueing ability for both (without code duplication). As part of the split into a PacketQueue and a port, there is now also a hierarchy of two port classes, QueuedPort and SimpleTimingPort. The QueuedPort is useful for ports that want to leave the packet transmission of outgoing packets to the queue and is used by both master and slave ports. The SimpleTimingPort inherits from the QueuedPort and adds the implemention of recvTiming and recvFunctional through recvAtomic. The PioPort and MessagePort are cleaned up as part of the changes. --HG-- rename : src/mem/tport.cc => src/mem/packet_queue.cc rename : src/mem/tport.hh => src/mem/packet_queue.hh
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protected:
Create a message port for sending messages as apposed to reading/writing a memory range.
2008-10-12 21:08:51 +02:00
Tick recvAtomic(PacketPtr pkt);
virtual Tick recvMessage(PacketPtr pkt) = 0;
MEM: Introduce the master/slave port sub-classes in C++ This patch introduces the notion of a master and slave port in the C++ code, thus bringing the previous classification from the Python classes into the corresponding simulation objects and memory objects. The patch enables us to classify behaviours into the two bins and add assumptions and enfore compliance, also simplifying the two interfaces. As a starting point, isSnooping is confined to a master port, and getAddrRanges to slave ports. More of these specilisations are to come in later patches. The getPort function is not getMasterPort and getSlavePort, and returns a port reference rather than a pointer as NULL would never be a valid return value. The default implementation of these two functions is placed in MemObject, and calls fatal. The one drawback with this specific patch is that it requires some code duplication, e.g. QueuedPort becomes QueuedMasterPort and QueuedSlavePort, and BusPort becomes BusMasterPort and BusSlavePort (avoiding multiple inheritance). With the later introduction of the port interfaces, moving the functionality outside the port itself, a lot of the duplicated code will disappear again.
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};
class MessageMasterPort : public QueuedMasterPort
{
public:
MessageMasterPort(const std::string &name, MemObject *owner) :
QueuedMasterPort(name, owner, queue), queue(*owner, *this)
{}
virtual ~MessageMasterPort()
{}
MEM: Separate snoops and normal memory requests/responses This patch introduces port access methods that separates snoop request/responses from normal memory request/responses. The differentiation is made for functional, atomic and timing accesses and builds on the introduction of master and slave ports. Before the introduction of this patch, the packets belonging to the different phases of the protocol (request -> [forwarded snoop request -> snoop response]* -> response) all use the same port access functions, even though the snoop packets flow in the opposite direction to the normal packet. That is, a coherent master sends normal request and receives responses, but receives snoop requests and sends snoop responses (vice versa for the slave). These two distinct phases now use different access functions, as described below. Starting with the functional access, a master sends a request to a slave through sendFunctional, and the request packet is turned into a response before the call returns. In a system without cache coherence, this is all that is needed from the functional interface. For the cache-coherent scenario, a slave also sends snoop requests to coherent masters through sendFunctionalSnoop, with responses returned within the same packet pointer. This is currently used by the bus and caches, and the LSQ of the O3 CPU. The send/recvFunctional and send/recvFunctionalSnoop are moved from the Port super class to the appropriate subclass. Atomic accesses follow the same flow as functional accesses, with request being sent from master to slave through sendAtomic. In the case of cache-coherent ports, a slave can send snoop requests to a master through sendAtomicSnoop. Just as for the functional access methods, the atomic send and receive member functions are moved to the appropriate subclasses. The timing access methods are different from the functional and atomic in that requests and responses are separated in time and send/recvTiming are used for both directions. Hence, a master uses sendTiming to send a request to a slave, and a slave uses sendTiming to send a response back to a master, at a later point in time. Snoop requests and responses travel in the opposite direction, similar to what happens in functional and atomic accesses. With the introduction of this patch, it is possible to determine the direction of packets in the bus, and no longer necessary to look for both a master and a slave port with the requested port id. In contrast to the normal recvFunctional, recvAtomic and recvTiming that are pure virtual functions, the recvFunctionalSnoop, recvAtomicSnoop and recvTimingSnoop have a default implementation that calls panic. This is to allow non-coherent master and slave ports to not implement these functions.
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bool recvTiming(PacketPtr pkt) { recvResponse(pkt); return true; }
MEM: Introduce the master/slave port sub-classes in C++ This patch introduces the notion of a master and slave port in the C++ code, thus bringing the previous classification from the Python classes into the corresponding simulation objects and memory objects. The patch enables us to classify behaviours into the two bins and add assumptions and enfore compliance, also simplifying the two interfaces. As a starting point, isSnooping is confined to a master port, and getAddrRanges to slave ports. More of these specilisations are to come in later patches. The getPort function is not getMasterPort and getSlavePort, and returns a port reference rather than a pointer as NULL would never be a valid return value. The default implementation of these two functions is placed in MemObject, and calls fatal. The one drawback with this specific patch is that it requires some code duplication, e.g. QueuedPort becomes QueuedMasterPort and QueuedSlavePort, and BusPort becomes BusMasterPort and BusSlavePort (avoiding multiple inheritance). With the later introduction of the port interfaces, moving the functionality outside the port itself, a lot of the duplicated code will disappear again.
2012-03-30 15:40:11 +02:00
protected:
/** A packet queue for outgoing packets. */
PacketQueue queue;
Create a message port for sending messages as apposed to reading/writing a memory range.
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// Accept and ignore responses.
virtual Tick recvResponse(PacketPtr pkt)
{
return 0;
}
};
#endif
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