The port on the side that receives requests and sends responses. More...

#include <bridge.hh>

Inheritance diagram for gem5::Bridge::BridgeResponsePort:

Public Member Functions
	BridgeResponsePort (const std::string &_name, Bridge &_bridge, BridgeRequestPort &_memSidePort, Cycles _delay, int _resp_limit, std::vector< AddrRange > _ranges)
	Constructor for the BridgeResponsePort.

void	schedTimingResp (PacketPtr pkt, Tick when)
	Queue a response packet to be sent out later and also schedule a send if necessary.

void	retryStalledReq ()
	Retry any stalled request that we have failed to accept at an earlier point in time.

Public Member Functions inherited from gem5::ResponsePort
	ResponsePort (const std::string &name, SimObject *_owner, PortID id=InvalidPortID)
	Response port.

	ResponsePort (const std::string &name, PortID id=InvalidPortID)

virtual	~ResponsePort ()

bool	isSnooping () const
	Find out if the peer request port is snooping or not.

void	sendRangeChange () const
	Called by the owner to send a range change.

void	unbind () override
	We let the request port do the work, so these don't do anything.

void	bind (Port &peer) override
	Attach to a peer port.

Tick	sendAtomicSnoop (PacketPtr pkt)
	Send an atomic snoop request packet, where the data is moved and the state is updated in zero time, without interleaving with other memory accesses.

void	sendFunctionalSnoop (PacketPtr pkt) const
	Send a functional snoop request packet, where the data is instantly updated everywhere in the memory system, without affecting the current state of any block or moving the block.

bool	sendTimingResp (PacketPtr pkt)
	Attempt to send a timing response to the request port by calling its corresponding receive function.

void	sendTimingSnoopReq (PacketPtr pkt)
	Attempt to send a timing snoop request packet to the request port by calling its corresponding receive function.

void	sendRetryReq ()
	Send a retry to the request port that previously attempted a sendTimingReq to this response port and failed.

void	sendRetrySnoopResp ()
	Send a retry to the request port that previously attempted a sendTimingSnoopResp to this response port and failed.

Public Member Functions inherited from gem5::Port
virtual	~Port ()
	Virtual destructor due to inheritance.

Port &	getPeer ()
	Return a reference to this port's peer.

const std::string	name () const
	Return port name (for DPRINTF).

PortID	getId () const
	Get the port id.

bool	isConnected () const
	Is this port currently connected to a peer?

void	takeOverFrom (Port *old)
	A utility function to make it easier to swap out ports.

Protected Member Functions
bool	recvTimingReq (PacketPtr pkt) override
	When receiving a timing request from the peer port, pass it to the bridge.

void	recvRespRetry () override
	When receiving a retry request from the peer port, pass it to the bridge.

Tick	recvAtomic (PacketPtr pkt) override
	When receiving an Atomic request from the peer port, pass it to the bridge.

Tick	recvAtomicBackdoor (PacketPtr pkt, MemBackdoorPtr &backdoor) override
	When receiving an Atomic backdoor request from the peer port, pass it to the bridge.

void	recvFunctional (PacketPtr pkt) override
	When receiving a Functional request from the peer port, pass it to the bridge.

void	recvMemBackdoorReq (const MemBackdoorReq &req, MemBackdoorPtr &backdoor) override
	When receiving a Functional backdoor request from the peer port, pass it to the bridge.

AddrRangeList	getAddrRanges () const override
	When receiving a address range request the peer port, pass it to the bridge.

Protected Member Functions inherited from gem5::ResponsePort
void	responderUnbind ()
	Called by the request port to unbind.

void	responderBind (RequestPort &request_port)
	Called by the request port to bind.

Tick	recvAtomicBackdoor (PacketPtr pkt, MemBackdoorPtr &backdoor) override
	Default implementations.

void	recvMemBackdoorReq (const MemBackdoorReq &req, MemBackdoorPtr &backdoor) override
	Receive a request for a back door to a range of memory.

bool	tryTiming (PacketPtr pkt) override
	Availability request from the peer.

bool	recvTimingSnoopResp (PacketPtr pkt) override
	Receive a timing snoop response from the peer.

Protected Member Functions inherited from gem5::Port
void	reportUnbound () const

	Port (const std::string &_name, PortID _id)
	Abstract base class for ports.

Protected Member Functions inherited from gem5::AtomicResponseProtocol
Tick	sendSnoop (AtomicRequestProtocol *peer, PacketPtr pkt)
	Send an atomic snoop request packet, where the data is moved and the state is updated in zero time, without interleaving with other memory accesses.

Protected Member Functions inherited from gem5::TimingResponseProtocol
bool	sendResp (TimingRequestProtocol *peer, PacketPtr pkt)
	Attempt to send a timing response to the peer by calling its corresponding receive function.

void	sendSnoopReq (TimingRequestProtocol *peer, PacketPtr pkt)
	Attempt to send a timing snoop request packet to the peer by calling its corresponding receive function.

void	sendRetryReq (TimingRequestProtocol *peer)
	Send a retry to the peer that previously attempted a sendTimingReq to this protocol and failed.

void	sendRetrySnoopResp (TimingRequestProtocol *peer)
	Send a retry to the peer that previously attempted a sendTimingSnoopResp to this peer and failed.

Protected Member Functions inherited from gem5::FunctionalResponseProtocol
void	sendSnoop (FunctionalRequestProtocol *peer, PacketPtr pkt) const
	Send a functional snoop request packet, where the data is instantly updated everywhere in the memory system, without affecting the current state of any block or moving the block.

Private Member Functions
bool	respQueueFull () const
	Is this side blocked from accepting new response packets.

void	trySendTiming ()
	Handle send event, scheduled when the packet at the head of the response queue is ready to transmit (for timing accesses only).

Private Attributes
Bridge &	bridge
	The bridge to which this port belongs.

BridgeRequestPort &	memSidePort
	Request port on the other side of the bridge.

const Cycles	delay
	Minimum request delay though this bridge.

const AddrRangeList	ranges
	Address ranges to pass through the bridge.

std::deque< DeferredPacket >	transmitList
	Response packet queue.

unsigned int	outstandingResponses
	Counter to track the outstanding responses.

bool	retryReq
	If we should send a retry when space becomes available.

unsigned int	respQueueLimit
	Max queue size for reserved responses.

std::unique_ptr< Packet >	pendingDelete
	Upstream caches need this packet until true is returned, so hold it for deletion until a subsequent call.

EventFunctionWrapper	sendEvent
	Send event for the response queue.

Additional Inherited Members
Protected Attributes inherited from gem5::ResponsePort
SimObject &	owner

Protected Attributes inherited from gem5::Port
const PortID	id
	A numeric identifier to distinguish ports in a vector, and set to InvalidPortID in case this port is not part of a vector.

Port *	_peer
	A pointer to this port's peer.

bool	_connected
	Whether this port is currently connected to a peer port.

Detailed Description

The port on the side that receives requests and sends responses.

The response port has a set of address ranges that it is responsible for. The response port also has a buffer for the responses not yet sent.

Definition at line 102 of file bridge.hh.

Constructor & Destructor Documentation

◆ BridgeResponsePort()

gem5::Bridge::BridgeResponsePort::BridgeResponsePort	(	const std::string &	_name,
		Bridge &	_bridge,
		BridgeRequestPort &	_memSidePort,
		Cycles	_delay,
		int	_resp_limit,
		std::vector< AddrRange >	_ranges )

Constructor for the BridgeResponsePort.

Parameters

_name	the port name including the owner
_bridge	the structural owner
_memSidePort	the request port on the other side of the bridge
_delay	the delay in cycles from receiving to sending
_resp_limit	the size of the response queue
_ranges	a number of address ranges to forward

Definition at line 56 of file bridge.cc.

References trySendTiming().

Member Function Documentation

◆ getAddrRanges()

AddrRangeList gem5::Bridge::BridgeResponsePort::getAddrRanges ( ) const

overrideprotectedvirtual

When receiving a address range request the peer port, pass it to the bridge.

Implements gem5::ResponsePort.

Definition at line 407 of file bridge.cc.

◆ recvAtomic()

Tick gem5::Bridge::BridgeResponsePort::recvAtomic ( PacketPtr pkt )

overrideprotectedvirtual

When receiving an Atomic request from the peer port, pass it to the bridge.

Implements gem5::AtomicResponseProtocol.

Definition at line 342 of file bridge.cc.

References gem5::Packet::cacheResponding(), gem5::Bridge::memSidePort, panic_if, and gem5::RequestPort::sendAtomic().

◆ recvAtomicBackdoor()

Tick gem5::Bridge::BridgeResponsePort::recvAtomicBackdoor	(	PacketPtr	pkt,
		MemBackdoorPtr &	backdoor )

overrideprotectedvirtual

When receiving an Atomic backdoor request from the peer port, pass it to the bridge.

Implements gem5::AtomicResponseProtocol.

Definition at line 351 of file bridge.cc.

References gem5::Bridge::memSidePort, and gem5::RequestPort::sendAtomicBackdoor().

◆ recvFunctional()

void gem5::Bridge::BridgeResponsePort::recvFunctional ( PacketPtr pkt )

overrideprotectedvirtual

When receiving a Functional request from the peer port, pass it to the bridge.

Implements gem5::FunctionalResponseProtocol.

Definition at line 359 of file bridge.cc.

References gem5::ArmISA::i, gem5::Packet::makeResponse(), gem5::Bridge::memSidePort, gem5::Named::name(), gem5::Packet::popLabel(), gem5::Packet::pushLabel(), gem5::RequestPort::sendFunctional(), gem5::Bridge::BridgeRequestPort::trySatisfyFunctional(), and gem5::Packet::trySatisfyFunctional().

◆ recvMemBackdoorReq()

void gem5::Bridge::BridgeResponsePort::recvMemBackdoorReq	(	const MemBackdoorReq &	req,
		MemBackdoorPtr &	backdoor )

overrideprotectedvirtual

When receiving a Functional backdoor request from the peer port, pass it to the bridge.

Implements gem5::FunctionalResponseProtocol.

Definition at line 383 of file bridge.cc.

References gem5::Bridge::memSidePort, and gem5::RequestPort::sendMemBackdoorReq().

◆ recvRespRetry()

void gem5::Bridge::BridgeResponsePort::recvRespRetry ( )

overrideprotectedvirtual

When receiving a retry request from the peer port, pass it to the bridge.

Implements gem5::TimingResponseProtocol.

Definition at line 336 of file bridge.cc.

◆ recvTimingReq()

bool gem5::Bridge::BridgeResponsePort::recvTimingReq ( PacketPtr pkt )

overrideprotectedvirtual

When receiving a timing request from the peer port, pass it to the bridge.

Implements gem5::TimingResponseProtocol.

Definition at line 147 of file bridge.cc.

References gem5::Packet::cacheResponding(), gem5::Packet::cmdString(), DPRINTF, gem5::Packet::getAddr(), gem5::Packet::headerDelay, gem5::Bridge::memSidePort, gem5::Packet::needsResponse(), panic_if, gem5::Packet::payloadDelay, gem5::Bridge::BridgeRequestPort::reqQueueFull(), and gem5::Bridge::BridgeRequestPort::schedTimingReq().

◆ respQueueFull()

bool gem5::Bridge::BridgeResponsePort::respQueueFull ( ) const

private

Is this side blocked from accepting new response packets.

Returns: true if the reserved space has reached the set limit

Definition at line 113 of file bridge.cc.

References outstandingResponses, and respQueueLimit.

◆ retryStalledReq()

void gem5::Bridge::BridgeResponsePort::retryStalledReq ( )

Retry any stalled request that we have failed to accept at an earlier point in time.

This call will do nothing if no request is waiting.

Definition at line 207 of file bridge.cc.

References DPRINTF.

Referenced by gem5::Bridge::BridgeRequestPort::trySendTiming().

◆ schedTimingResp()

void gem5::Bridge::BridgeResponsePort::schedTimingResp	(	PacketPtr	pkt,
		Tick	when )

Queue a response packet to be sent out later and also schedule a send if necessary.

Parameters

pkt	a response to send out after a delay
when	tick when response packet should be sent

Definition at line 234 of file bridge.cc.

References gem5::ArmISA::sendEvent().

Referenced by gem5::Bridge::BridgeRequestPort::recvTimingResp().

◆ trySendTiming()

void gem5::Bridge::BridgeResponsePort::trySendTiming ( )

private

Handle send event, scheduled when the packet at the head of the response queue is ready to transmit (for timing accesses only).

Definition at line 286 of file bridge.cc.

References gem5::curTick(), DPRINTF, gem5::Packet::getAddr(), gem5::Bridge::memSidePort, gem5::Bridge::DeferredPacket::pkt, gem5::Bridge::BridgeRequestPort::reqQueueFull(), gem5::ArmISA::sendEvent(), and gem5::Bridge::DeferredPacket::tick.

Referenced by BridgeResponsePort().

Member Data Documentation

◆ bridge

Bridge& gem5::Bridge::BridgeResponsePort::bridge

private

The bridge to which this port belongs.

Definition at line 108 of file bridge.hh.

◆ delay

const Cycles gem5::Bridge::BridgeResponsePort::delay

private

Minimum request delay though this bridge.

Definition at line 116 of file bridge.hh.

◆ memSidePort

BridgeRequestPort& gem5::Bridge::BridgeResponsePort::memSidePort

private

Request port on the other side of the bridge.

Definition at line 113 of file bridge.hh.

◆ outstandingResponses

unsigned int gem5::Bridge::BridgeResponsePort::outstandingResponses

private

Counter to track the outstanding responses.

Definition at line 130 of file bridge.hh.

Referenced by respQueueFull().

◆ pendingDelete

std::unique_ptr<Packet> gem5::Bridge::BridgeResponsePort::pendingDelete

private

Upstream caches need this packet until true is returned, so hold it for deletion until a subsequent call.

Definition at line 142 of file bridge.hh.

◆ ranges

const AddrRangeList gem5::Bridge::BridgeResponsePort::ranges

private

Address ranges to pass through the bridge.

Definition at line 119 of file bridge.hh.

◆ respQueueLimit

unsigned int gem5::Bridge::BridgeResponsePort::respQueueLimit

private

Max queue size for reserved responses.

Definition at line 136 of file bridge.hh.

Referenced by respQueueFull().

◆ retryReq

bool gem5::Bridge::BridgeResponsePort::retryReq

private

If we should send a retry when space becomes available.

Definition at line 133 of file bridge.hh.

◆ sendEvent

EventFunctionWrapper gem5::Bridge::BridgeResponsePort::sendEvent

private

Send event for the response queue.

Definition at line 159 of file bridge.hh.

◆ transmitList

std::deque<DeferredPacket> gem5::Bridge::BridgeResponsePort::transmitList

private

Response packet queue.

Response packets are held in this queue for a specified delay to model the processing delay of the bridge. We use a deque as we need to iterate over the items for functional accesses.

Definition at line 127 of file bridge.hh.

The documentation for this class was generated from the following files:

mem/bridge.hh
mem/bridge.cc

Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ BridgeResponsePort()

Member Function Documentation

◆ getAddrRanges()

◆ recvAtomic()

◆ recvAtomicBackdoor()

◆ recvFunctional()

◆ recvMemBackdoorReq()

◆ recvRespRetry()

◆ recvTimingReq()

◆ respQueueFull()

◆ retryStalledReq()

◆ schedTimingResp()

◆ trySendTiming()

Member Data Documentation

◆ bridge

◆ delay

◆ memSidePort

◆ outstandingResponses

◆ pendingDelete

◆ ranges

◆ respQueueLimit

◆ retryReq

◆ sendEvent

◆ transmitList