2006-04-28 21:37:48 +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.
2012-03-30 15:40:11 +02:00
|
|
|
* Copyright (c) 2011-2012 ARM Limited
|
2012-01-17 19:55:09 +01:00
|
|
|
* 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.
|
|
|
|
*
|
2006-04-28 21:37:48 +02:00
|
|
|
* Copyright (c) 2006 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.
|
2006-06-01 01:26:56 +02:00
|
|
|
*
|
|
|
|
* Authors: Ali Saidi
|
|
|
|
* Steve Reinhardt
|
2012-01-17 19:55:09 +01:00
|
|
|
* Andreas Hansson
|
2006-04-28 21:37:48 +02:00
|
|
|
*/
|
|
|
|
|
|
|
|
/**
|
2006-08-15 01:25:07 +02:00
|
|
|
* @file
|
2012-01-17 19:55:09 +01:00
|
|
|
* Declaration of a memory-mapped bus bridge that connects a master
|
|
|
|
* and a slave through a request and response queue.
|
2006-04-28 21:37:48 +02:00
|
|
|
*/
|
|
|
|
|
|
|
|
#ifndef __MEM_BRIDGE_HH__
|
|
|
|
#define __MEM_BRIDGE_HH__
|
|
|
|
|
|
|
|
#include <list>
|
|
|
|
#include <queue>
|
2011-04-15 19:44:06 +02:00
|
|
|
#include <string>
|
2006-04-28 21:37:48 +02:00
|
|
|
|
2008-03-24 06:08:02 +01:00
|
|
|
#include "base/fast_alloc.hh"
|
2009-05-17 23:34:51 +02:00
|
|
|
#include "base/types.hh"
|
2006-04-28 21:37:48 +02:00
|
|
|
#include "mem/mem_object.hh"
|
|
|
|
#include "mem/packet.hh"
|
|
|
|
#include "mem/port.hh"
|
2007-07-24 06:51:38 +02:00
|
|
|
#include "params/Bridge.hh"
|
2006-04-28 21:37:48 +02:00
|
|
|
#include "sim/eventq.hh"
|
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/**
|
|
|
|
* A bridge is used to interface two different busses (or in general a
|
|
|
|
* memory-mapped master and slave), with buffering for requests and
|
|
|
|
* responses. The bridge has a fixed delay for packets passing through
|
|
|
|
* it and responds to a fixed set of address ranges.
|
|
|
|
*
|
|
|
|
* The bridge comprises a slave port and a master port, that buffer
|
|
|
|
* outgoing responses and requests respectively. Buffer space is
|
|
|
|
* reserved when a request arrives, also reserving response space
|
|
|
|
* before forwarding the request. An incoming request is always
|
|
|
|
* accepted (recvTiming returns true), but is potentially NACKed if
|
|
|
|
* there is no request space or response space.
|
|
|
|
*/
|
2006-04-28 21:37:48 +02:00
|
|
|
class Bridge : public MemObject
|
|
|
|
{
|
2006-05-26 20:29:29 +02:00
|
|
|
protected:
|
2012-01-17 19:55:09 +01:00
|
|
|
|
|
|
|
/**
|
2012-05-30 11:28:06 +02:00
|
|
|
* A bridge request state stores packets along with their sender
|
|
|
|
* state and original source. It has enough information to also
|
|
|
|
* restore the response once it comes back to the bridge.
|
2012-01-17 19:55:09 +01:00
|
|
|
*/
|
2012-05-30 11:28:06 +02:00
|
|
|
class RequestState : public Packet::SenderState, public FastAlloc
|
|
|
|
{
|
2012-01-17 19:55:09 +01:00
|
|
|
|
|
|
|
public:
|
2012-05-30 11:28:06 +02:00
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
Packet::SenderState *origSenderState;
|
MEM: Remove the Broadcast destination from the packet
This patch simplifies the packet by removing the broadcast flag and
instead more firmly relying on (and enforcing) the semantics of
transactions in the classic memory system, i.e. request packets are
routed from a master to a slave based on the address, and when they
are created they have neither a valid source, nor destination. On
their way to the slave, the request packet is updated with a source
field for all modules that multiplex packets from multiple master
(e.g. a bus). When a request packet is turned into a response packet
(at the final slave), it moves the potentially populated source field
to the destination field, and the response packet is routed through
any multiplexing components back to the master based on the
destination field.
Modules that connect multiplexing components, such as caches and
bridges store any existing source and destination field in the sender
state as a stack (just as before).
The packet constructor is simplified in that there is no longer a need
to pass the Packet::Broadcast as the destination (this was always the
case for the classic memory system). In the case of Ruby, rather than
using the parameter to the constructor we now rely on setDest, as
there is already another three-argument constructor in the packet
class.
In many places where the packet information was printed as part of
DPRINTFs, request packets would be printed with a numeric "dest" that
would always be -1 (Broadcast) and that field is now removed from the
printing.
2012-04-14 11:45:55 +02:00
|
|
|
Packet::NodeID origSrc;
|
2012-01-17 19:55:09 +01:00
|
|
|
|
2012-05-30 11:28:06 +02:00
|
|
|
RequestState(PacketPtr _pkt)
|
|
|
|
: origSenderState(_pkt->senderState),
|
|
|
|
origSrc(_pkt->getSrc())
|
|
|
|
{ }
|
2012-01-17 19:55:09 +01:00
|
|
|
|
|
|
|
void fixResponse(PacketPtr pkt)
|
|
|
|
{
|
|
|
|
assert(pkt->senderState == this);
|
|
|
|
pkt->setDest(origSrc);
|
|
|
|
pkt->senderState = origSenderState;
|
|
|
|
}
|
|
|
|
};
|
|
|
|
|
2012-05-30 11:28:06 +02:00
|
|
|
/**
|
|
|
|
* A deferred request stores a packet along with its scheduled
|
|
|
|
* transmission time, and whether we can expect to see a response
|
|
|
|
* or not.
|
|
|
|
*/
|
|
|
|
class DeferredRequest
|
|
|
|
{
|
|
|
|
|
|
|
|
public:
|
|
|
|
|
|
|
|
Tick ready;
|
|
|
|
PacketPtr pkt;
|
|
|
|
bool expectResponse;
|
|
|
|
|
|
|
|
DeferredRequest(PacketPtr _pkt, Tick t)
|
|
|
|
: ready(t), pkt(_pkt), expectResponse(_pkt->needsResponse())
|
|
|
|
{ }
|
|
|
|
};
|
|
|
|
|
|
|
|
/**
|
|
|
|
* A deferred response stores a packet along with its scheduled
|
|
|
|
* transmission time. It also contains information of whether the
|
|
|
|
* bridge NACKed the packet to be able to correctly maintain
|
|
|
|
* counters of outstanding responses.
|
|
|
|
*/
|
|
|
|
class DeferredResponse {
|
|
|
|
|
|
|
|
public:
|
|
|
|
|
|
|
|
Tick ready;
|
|
|
|
PacketPtr pkt;
|
|
|
|
bool nackedHere;
|
|
|
|
|
|
|
|
DeferredResponse(PacketPtr _pkt, Tick t, bool nack = false)
|
|
|
|
: ready(t), pkt(_pkt), nackedHere(nack)
|
|
|
|
{ }
|
|
|
|
};
|
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
// Forward declaration to allow the slave port to have a pointer
|
|
|
|
class BridgeMasterPort;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* The port on the side that receives requests and sends
|
|
|
|
* responses. The slave port has a set of address ranges that it
|
|
|
|
* is responsible for. The slave port also has a buffer for the
|
|
|
|
* responses not yet sent.
|
|
|
|
*/
|
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
|
|
|
class BridgeSlavePort : public SlavePort
|
2006-04-28 21:37:48 +02:00
|
|
|
{
|
2012-01-17 19:55:09 +01:00
|
|
|
|
|
|
|
private:
|
|
|
|
|
2006-05-26 20:29:29 +02:00
|
|
|
/** A pointer to the bridge to which this port belongs. */
|
|
|
|
Bridge *bridge;
|
2006-04-28 21:37:48 +02:00
|
|
|
|
2006-05-26 20:29:29 +02:00
|
|
|
/**
|
2012-02-24 17:43:53 +01:00
|
|
|
* Master port on the other side of the bridge
|
2006-05-26 20:29:29 +02:00
|
|
|
* (connected to the other bus).
|
|
|
|
*/
|
2012-02-24 17:43:53 +01:00
|
|
|
BridgeMasterPort& masterPort;
|
2006-04-28 21:37:48 +02:00
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/** Minimum request delay though this bridge. */
|
2006-05-26 20:29:29 +02:00
|
|
|
Tick delay;
|
2006-04-28 21:37:48 +02:00
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/** Min delay to respond with a nack. */
|
2007-05-10 00:20:24 +02:00
|
|
|
Tick nackDelay;
|
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/** Address ranges to pass through the bridge */
|
|
|
|
AddrRangeList ranges;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Response packet queue. Response packets are held in this
|
|
|
|
* queue for a specified delay to model the processing delay
|
|
|
|
* of the bridge.
|
|
|
|
*/
|
2012-05-30 11:28:06 +02:00
|
|
|
std::list<DeferredResponse> responseQueue;
|
2007-05-07 20:42:03 +02:00
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/** Counter to track the outstanding responses. */
|
|
|
|
unsigned int outstandingResponses;
|
|
|
|
|
|
|
|
/** If we're waiting for a retry to happen. */
|
|
|
|
bool inRetry;
|
|
|
|
|
|
|
|
/** Max queue size for reserved responses. */
|
|
|
|
unsigned int respQueueLimit;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Is this side blocked from accepting new response packets.
|
|
|
|
*
|
|
|
|
* @return true if the reserved space has reached the set limit
|
|
|
|
*/
|
|
|
|
bool respQueueFull();
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Turn the request packet into a NACK response and put it in
|
|
|
|
* the response queue and schedule its transmission.
|
|
|
|
*
|
|
|
|
* @param pkt the request packet to NACK
|
|
|
|
*/
|
|
|
|
void nackRequest(PacketPtr pkt);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Handle send event, scheduled when the packet at the head of
|
|
|
|
* the response queue is ready to transmit (for timing
|
|
|
|
* accesses only).
|
|
|
|
*/
|
|
|
|
void trySend();
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Private class for scheduling sending of responses from the
|
|
|
|
* response queue.
|
|
|
|
*/
|
|
|
|
class SendEvent : public Event
|
|
|
|
{
|
2012-02-24 17:43:53 +01:00
|
|
|
BridgeSlavePort& port;
|
2006-04-28 21:37:48 +02:00
|
|
|
|
2006-05-26 20:29:29 +02:00
|
|
|
public:
|
2012-02-24 17:43:53 +01:00
|
|
|
SendEvent(BridgeSlavePort& p) : port(p) {}
|
|
|
|
virtual void process() { port.trySend(); }
|
2012-01-17 19:55:09 +01:00
|
|
|
virtual const char *description() const { return "bridge send"; }
|
2006-05-26 20:29:29 +02:00
|
|
|
};
|
2006-04-28 21:37:48 +02:00
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/** Send event for the response queue. */
|
|
|
|
SendEvent sendEvent;
|
|
|
|
|
|
|
|
public:
|
|
|
|
|
2006-05-26 20:29:29 +02:00
|
|
|
/**
|
2012-01-17 19:55:09 +01:00
|
|
|
* Constructor for the BridgeSlavePort.
|
|
|
|
*
|
|
|
|
* @param _name the port name including the owner
|
|
|
|
* @param _bridge the structural owner
|
|
|
|
* @param _masterPort the master port on the other side of the bridge
|
|
|
|
* @param _delay the delay from seeing a response to sending it
|
|
|
|
* @param _nack_delay the delay from a NACK to sending the response
|
|
|
|
* @param _resp_limit the size of the response queue
|
|
|
|
* @param _ranges a number of address ranges to forward
|
2006-05-26 20:29:29 +02:00
|
|
|
*/
|
2012-01-17 19:55:09 +01:00
|
|
|
BridgeSlavePort(const std::string &_name, Bridge *_bridge,
|
2012-02-24 17:43:53 +01:00
|
|
|
BridgeMasterPort& _masterPort, int _delay,
|
2012-01-17 19:55:09 +01:00
|
|
|
int _nack_delay, int _resp_limit,
|
|
|
|
std::vector<Range<Addr> > _ranges);
|
2006-04-28 21:37:48 +02:00
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/**
|
|
|
|
* Queue a response packet to be sent out later and also schedule
|
|
|
|
* a send if necessary.
|
|
|
|
*
|
|
|
|
* @param pkt a response to send out after a delay
|
|
|
|
*/
|
|
|
|
void queueForSendTiming(PacketPtr pkt);
|
2006-05-26 20:29:29 +02:00
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
protected:
|
2007-05-10 00:20:24 +02:00
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/** When receiving a timing request from the peer port,
|
|
|
|
pass it to the bridge. */
|
MEM: Separate requests and responses for timing accesses
This patch moves send/recvTiming and send/recvTimingSnoop from the
Port base class to the MasterPort and SlavePort, and also splits them
into separate member functions for requests and responses:
send/recvTimingReq, send/recvTimingResp, and send/recvTimingSnoopReq,
send/recvTimingSnoopResp. A master port sends requests and receives
responses, and also receives snoop requests and sends snoop
responses. A slave port has the reciprocal behaviour as it receives
requests and sends responses, and sends snoop requests and receives
snoop responses.
For all MemObjects that have only master ports or slave ports (but not
both), e.g. a CPU, or a PIO device, this patch merely adds more
clarity to what kind of access is taking place. For example, a CPU
port used to call sendTiming, and will now call
sendTimingReq. Similarly, a response previously came back through
recvTiming, which is now recvTimingResp. For the modules that have
both master and slave ports, e.g. the bus, the behaviour was
previously relying on branches based on pkt->isRequest(), and this is
now replaced with a direct call to the apprioriate member function
depending on the type of access. Please note that send/recvRetry is
still shared by all the timing accessors and remains in the Port base
class for now (to maintain the current bus functionality and avoid
changing the statistics of all regressions).
The packet queue is split into a MasterPort and SlavePort version to
facilitate the use of the new timing accessors. All uses of the
PacketQueue are updated accordingly.
With this patch, the type of packet (request or response) is now well
defined for each type of access, and asserts on pkt->isRequest() and
pkt->isResponse() are now moved to the appropriate send member
functions. It is also worth noting that sendTimingSnoopReq no longer
returns a boolean, as the semantics do not alow snoop requests to be
rejected or stalled. All these assumptions are now excplicitly part of
the port interface itself.
2012-05-01 19:40:42 +02:00
|
|
|
virtual bool recvTimingReq(PacketPtr pkt);
|
2007-05-10 00:20:24 +02:00
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/** When receiving a retry request from the peer port,
|
|
|
|
pass it to the bridge. */
|
|
|
|
virtual void recvRetry();
|
|
|
|
|
|
|
|
/** When receiving a Atomic requestfrom the peer port,
|
|
|
|
pass it to the bridge. */
|
|
|
|
virtual Tick recvAtomic(PacketPtr pkt);
|
|
|
|
|
|
|
|
/** When receiving a Functional request from the peer port,
|
|
|
|
pass it to the bridge. */
|
|
|
|
virtual void recvFunctional(PacketPtr pkt);
|
2006-05-26 20:29:29 +02:00
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/** When receiving a address range request the peer port,
|
|
|
|
pass it to the bridge. */
|
|
|
|
virtual AddrRangeList getAddrRanges();
|
|
|
|
};
|
2006-05-26 20:29:29 +02:00
|
|
|
|
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/**
|
|
|
|
* Port on the side that forwards requests and receives
|
|
|
|
* responses. The master port has a buffer for the requests not
|
|
|
|
* yet sent.
|
|
|
|
*/
|
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
|
|
|
class BridgeMasterPort : public MasterPort
|
2012-01-17 19:55:09 +01:00
|
|
|
{
|
|
|
|
|
|
|
|
private:
|
|
|
|
|
|
|
|
/** A pointer to the bridge to which this port belongs. */
|
|
|
|
Bridge* bridge;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Pointer to the slave port on the other side of the bridge
|
|
|
|
* (connected to the other bus).
|
|
|
|
*/
|
2012-02-24 17:43:53 +01:00
|
|
|
BridgeSlavePort& slavePort;
|
2012-01-17 19:55:09 +01:00
|
|
|
|
|
|
|
/** Minimum delay though this bridge. */
|
|
|
|
Tick delay;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Request packet queue. Request packets are held in this
|
|
|
|
* queue for a specified delay to model the processing delay
|
|
|
|
* of the bridge.
|
|
|
|
*/
|
2012-05-30 11:28:06 +02:00
|
|
|
std::list<DeferredRequest> requestQueue;
|
2012-01-17 19:55:09 +01:00
|
|
|
|
|
|
|
/** If we're waiting for a retry to happen. */
|
|
|
|
bool inRetry;
|
|
|
|
|
|
|
|
/** Max queue size for request packets */
|
|
|
|
unsigned int reqQueueLimit;
|
2007-05-08 00:58:38 +02:00
|
|
|
|
2006-05-26 20:29:29 +02:00
|
|
|
/**
|
|
|
|
* Handle send event, scheduled when the packet at the head of
|
|
|
|
* the outbound queue is ready to transmit (for timing
|
|
|
|
* accesses only).
|
|
|
|
*/
|
|
|
|
void trySend();
|
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/**
|
|
|
|
* Private class for scheduling sending of requests from the
|
|
|
|
* request queue.
|
|
|
|
*/
|
2006-05-26 20:29:29 +02:00
|
|
|
class SendEvent : public Event
|
|
|
|
{
|
2012-02-24 17:43:53 +01:00
|
|
|
BridgeMasterPort& port;
|
2006-05-26 20:29:29 +02:00
|
|
|
|
|
|
|
public:
|
2012-02-24 17:43:53 +01:00
|
|
|
SendEvent(BridgeMasterPort& p) : port(p) {}
|
|
|
|
virtual void process() { port.trySend(); }
|
2008-02-06 22:32:40 +01:00
|
|
|
virtual const char *description() const { return "bridge send"; }
|
2006-05-26 20:29:29 +02:00
|
|
|
};
|
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/** Send event for the request queue. */
|
2006-05-26 20:29:29 +02:00
|
|
|
SendEvent sendEvent;
|
2006-04-28 21:37:48 +02:00
|
|
|
|
|
|
|
public:
|
2012-01-17 19:55:09 +01:00
|
|
|
|
|
|
|
/**
|
|
|
|
* Constructor for the BridgeMasterPort.
|
|
|
|
*
|
|
|
|
* @param _name the port name including the owner
|
|
|
|
* @param _bridge the structural owner
|
|
|
|
* @param _slavePort the slave port on the other side of the bridge
|
|
|
|
* @param _delay the delay from seeing a request to sending it
|
|
|
|
* @param _req_limit the size of the request queue
|
|
|
|
*/
|
|
|
|
BridgeMasterPort(const std::string &_name, Bridge *_bridge,
|
2012-02-24 17:43:53 +01:00
|
|
|
BridgeSlavePort& _slavePort, int _delay,
|
2012-01-17 19:55:09 +01:00
|
|
|
int _req_limit);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Is this side blocked from accepting new request packets.
|
|
|
|
*
|
|
|
|
* @return true if the occupied space has reached the set limit
|
|
|
|
*/
|
|
|
|
bool reqQueueFull();
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Queue a request packet to be sent out later and also schedule
|
|
|
|
* a send if necessary.
|
|
|
|
*
|
|
|
|
* @param pkt a request to send out after a delay
|
|
|
|
*/
|
|
|
|
void queueForSendTiming(PacketPtr pkt);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Check a functional request against the packets in our
|
|
|
|
* request queue.
|
|
|
|
*
|
|
|
|
* @param pkt packet to check against
|
|
|
|
*
|
|
|
|
* @return true if we find a match
|
|
|
|
*/
|
|
|
|
bool checkFunctional(PacketPtr pkt);
|
2006-04-28 21:37:48 +02:00
|
|
|
|
|
|
|
protected:
|
|
|
|
|
2006-05-26 20:29:29 +02:00
|
|
|
/** When receiving a timing request from the peer port,
|
2006-04-28 21:37:48 +02:00
|
|
|
pass it to the bridge. */
|
MEM: Separate requests and responses for timing accesses
This patch moves send/recvTiming and send/recvTimingSnoop from the
Port base class to the MasterPort and SlavePort, and also splits them
into separate member functions for requests and responses:
send/recvTimingReq, send/recvTimingResp, and send/recvTimingSnoopReq,
send/recvTimingSnoopResp. A master port sends requests and receives
responses, and also receives snoop requests and sends snoop
responses. A slave port has the reciprocal behaviour as it receives
requests and sends responses, and sends snoop requests and receives
snoop responses.
For all MemObjects that have only master ports or slave ports (but not
both), e.g. a CPU, or a PIO device, this patch merely adds more
clarity to what kind of access is taking place. For example, a CPU
port used to call sendTiming, and will now call
sendTimingReq. Similarly, a response previously came back through
recvTiming, which is now recvTimingResp. For the modules that have
both master and slave ports, e.g. the bus, the behaviour was
previously relying on branches based on pkt->isRequest(), and this is
now replaced with a direct call to the apprioriate member function
depending on the type of access. Please note that send/recvRetry is
still shared by all the timing accessors and remains in the Port base
class for now (to maintain the current bus functionality and avoid
changing the statistics of all regressions).
The packet queue is split into a MasterPort and SlavePort version to
facilitate the use of the new timing accessors. All uses of the
PacketQueue are updated accordingly.
With this patch, the type of packet (request or response) is now well
defined for each type of access, and asserts on pkt->isRequest() and
pkt->isResponse() are now moved to the appropriate send member
functions. It is also worth noting that sendTimingSnoopReq no longer
returns a boolean, as the semantics do not alow snoop requests to be
rejected or stalled. All these assumptions are now excplicitly part of
the port interface itself.
2012-05-01 19:40:42 +02:00
|
|
|
virtual bool recvTimingResp(PacketPtr pkt);
|
2006-04-28 21:37:48 +02:00
|
|
|
|
2006-05-26 20:29:29 +02:00
|
|
|
/** When receiving a retry request from the peer port,
|
2006-04-28 21:37:48 +02:00
|
|
|
pass it to the bridge. */
|
2006-05-31 00:57:42 +02:00
|
|
|
virtual void recvRetry();
|
2006-04-28 21:37:48 +02:00
|
|
|
};
|
|
|
|
|
2012-01-17 19:55:09 +01:00
|
|
|
/** Slave port of the bridge. */
|
|
|
|
BridgeSlavePort slavePort;
|
|
|
|
|
|
|
|
/** Master port of the bridge. */
|
|
|
|
BridgeMasterPort masterPort;
|
2006-04-28 21:37:48 +02:00
|
|
|
|
|
|
|
/** If this bridge should acknowledge writes. */
|
|
|
|
bool ackWrites;
|
|
|
|
|
|
|
|
public:
|
2007-07-24 06:51:38 +02:00
|
|
|
typedef BridgeParams Params;
|
2007-05-10 00:20:24 +02:00
|
|
|
|
|
|
|
protected:
|
|
|
|
Params *_params;
|
|
|
|
|
|
|
|
public:
|
|
|
|
const Params *params() const { return _params; }
|
2006-04-28 21:37:48 +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.
2012-03-30 15:40:11 +02:00
|
|
|
virtual MasterPort& getMasterPort(const std::string& if_name,
|
|
|
|
int idx = -1);
|
|
|
|
virtual SlavePort& getSlavePort(const std::string& if_name, int idx = -1);
|
2006-04-28 21:37:48 +02:00
|
|
|
|
|
|
|
virtual void init();
|
|
|
|
|
2007-05-10 00:20:24 +02:00
|
|
|
Bridge(Params *p);
|
2006-04-28 21:37:48 +02:00
|
|
|
};
|
|
|
|
|
|
|
|
#endif //__MEM_BUS_HH__
|