A non-coherent crossbar connects a number of non-snooping masters and slaves, and routes the request and response packets based on the address. More...

#include <noncoherent_xbar.hh>

Inheritance diagram for NoncoherentXBar:

Classes
class	NoncoherentXBarMasterPort
	Declaration of the crossbar master port type, one will be instantiated for each of the slave ports connecting to the crossbar. More...

class	NoncoherentXBarSlavePort
	Declaration of the non-coherent crossbar slave port type, one will be instantiated for each of the master ports connecting to the crossbar. More...

Public Member Functions
	NoncoherentXBar (const NoncoherentXBarParams *p)

virtual	~NoncoherentXBar ()

virtual void	regStats ()
	stats More...

Public Member Functions inherited from BaseXBar
virtual	~BaseXBar ()

virtual void	init ()
	init() is called after all C++ SimObjects have been created and all ports are connected. More...

BaseMasterPort &	getMasterPort (const std::string &if_name, PortID idx=InvalidPortID)
	A function used to return the port associated with this object. More...

BaseSlavePort &	getSlavePort (const std::string &if_name, PortID idx=InvalidPortID)
	Get a slave port with a given name and index. More...

Public Member Functions inherited from MemObject
const Params *	params () const

	MemObject (const Params *params)

Public Member Functions inherited from ClockedObject
	ClockedObject (const ClockedObjectParams *p)

const Params *	params () const

void	serialize (CheckpointOut &cp) const override
	Serialize an object. More...

void	unserialize (CheckpointIn &cp) override
	Unserialize an object. More...

Enums::PwrState	pwrState () const

std::string	pwrStateName () const

std::vector< double >	pwrStateWeights () const
	Returns the percentage residency for each power state. More...

void	computeStats ()
	Record stats values like state residency by computing the time difference from previous update. More...

void	pwrState (Enums::PwrState)

void	regStats () override
	Register statistics for this object. More...

Public Member Functions inherited from SimObject
const Params *	params () const

	SimObject (const Params *_params)

virtual	~SimObject ()

virtual const std::string	name () const

virtual void	loadState (CheckpointIn &cp)
	loadState() is called on each SimObject when restoring from a checkpoint. More...

virtual void	initState ()
	initState() is called on each SimObject when not restoring from a checkpoint. More...

virtual void	resetStats ()
	Reset statistics associated with this object. More...

virtual void	regProbePoints ()
	Register probe points for this object. More...

virtual void	regProbeListeners ()
	Register probe listeners for this object. More...

ProbeManager *	getProbeManager ()
	Get the probe manager for this object. More...

virtual void	startup ()
	startup() is the final initialization call before simulation. More...

DrainState	drain () override
	Provide a default implementation of the drain interface for objects that don't need draining. More...

virtual void	memWriteback ()
	Write back dirty buffers to memory using functional writes. More...

virtual void	memInvalidate ()
	Invalidate the contents of memory buffers. More...

void	serialize (CheckpointOut &cp) const override
	Serialize an object. More...

void	unserialize (CheckpointIn &cp) override
	Unserialize an object. More...

Public Member Functions inherited from EventManager
	EventManager (EventManager &em)

	EventManager (EventManager *em)

	EventManager (EventQueue *eq)

EventQueue *	eventQueue () const

void	schedule (Event &event, Tick when)

void	deschedule (Event &event)

void	reschedule (Event &event, Tick when, bool always=false)

void	schedule (Event *event, Tick when)

void	deschedule (Event *event)

void	reschedule (Event *event, Tick when, bool always=false)

void	wakeupEventQueue (Tick when=(Tick)-1)

void	setCurTick (Tick newVal)

Public Member Functions inherited from Serializable
	Serializable ()

virtual	~Serializable ()

void	serializeSection (CheckpointOut &cp, const char *name) const
	Serialize an object into a new section. More...

void	serializeSection (CheckpointOut &cp, const std::string &name) const

void	unserializeSection (CheckpointIn &cp, const char *name)
	Unserialize an a child object. More...

void	unserializeSection (CheckpointIn &cp, const std::string &name)

Public Member Functions inherited from Drainable
DrainState	drainState () const
	Return the current drain state of an object. More...

virtual void	notifyFork ()
	Notify a child process of a fork. More...

Public Member Functions inherited from Clocked
void	updateClockPeriod () const
	Update the tick to the current tick. More...

Tick	clockEdge (Cycles cycles=Cycles(0)) const
	Determine the tick when a cycle begins, by default the current one, but the argument also enables the caller to determine a future cycle. More...

Cycles	curCycle () const
	Determine the current cycle, corresponding to a tick aligned to a clock edge. More...

Tick	nextCycle () const
	Based on the clock of the object, determine the start tick of the first cycle that is at least one cycle in the future. More...

uint64_t	frequency () const

Tick	clockPeriod () const

double	voltage () const

Cycles	ticksToCycles (Tick t) const

Tick	cyclesToTicks (Cycles c) const

Public Attributes
Stats::Scalar	totPktSize

Protected Member Functions
virtual bool	recvTimingReq (PacketPtr pkt, PortID slave_port_id)
	Function called by the port when the crossbar is recieving a Timing request packet. More...

virtual bool	recvTimingResp (PacketPtr pkt, PortID master_port_id)
	Function called by the port when the crossbar is recieving a Timing response packet. More...

void	recvReqRetry (PortID master_port_id)
	Timing function called by port when it is once again able to process requests. More...

Tick	recvAtomic (PacketPtr pkt, PortID slave_port_id)
	Function called by the port when the crossbar is recieving a Atomic transaction. More...

void	recvFunctional (PacketPtr pkt, PortID slave_port_id)
	Function called by the port when the crossbar is recieving a Functional transaction. More...

Protected Member Functions inherited from BaseXBar
virtual void	recvRangeChange (PortID master_port_id)
	Function called by the port when the crossbar is recieving a range change. More...

PortID	findPort (Addr addr)
	Find which port connected to this crossbar (if any) should be given a packet with this address. More...

PortID	checkPortCache (Addr addr) const

void	updatePortCache (short id, const AddrRange &range)

void	clearPortCache ()

AddrRangeList	getAddrRanges () const
	Return the address ranges the crossbar is responsible for. More...

void	calcPacketTiming (PacketPtr pkt, Tick header_delay)
	Calculate the timing parameters for the packet. More...

	BaseXBar (const BaseXBarParams *p)

Protected Member Functions inherited from Drainable
	Drainable ()

virtual	~Drainable ()

virtual void	drainResume ()
	Resume execution after a successful drain. More...

void	signalDrainDone () const
	Signal that an object is drained. More...

Protected Member Functions inherited from Clocked
	Clocked (ClockDomain &clk_domain)
	Create a clocked object and set the clock domain based on the parameters. More...

	Clocked (Clocked &)=delete

Clocked &	operator= (Clocked &)=delete

virtual	~Clocked ()
	Virtual destructor due to inheritance. More...

void	resetClock () const
	Reset the object's clock using the current global tick value. More...

Protected Attributes
std::vector< ReqLayer * >	reqLayers
	Declare the layers of this crossbar, one vector for requests and one for responses. More...

std::vector< RespLayer * >	respLayers

Protected Attributes inherited from BaseXBar
const Cycles	frontendLatency
	Cycles of front-end pipeline including the delay to accept the request and to decode the address. More...

const Cycles	forwardLatency
	Cycles of forward latency. More...

const Cycles	responseLatency
	Cycles of response latency. More...

const uint32_t	width
	the width of the xbar in bytes More...

AddrRangeMap< PortID >	portMap

std::unordered_map< RequestPtr, PortID >	routeTo
	Remember where request packets came from so that we can route responses to the appropriate port. More...

AddrRangeList	xbarRanges
	all contigous ranges seen by this crossbar More...

AddrRange	defaultRange

PortCache	portCache [3]

std::vector< bool >	gotAddrRanges
	Remember for each of the master ports of the crossbar if we got an address range from the connected slave. More...

bool	gotAllAddrRanges

std::vector< QueuedSlavePort * >	slavePorts
	The master and slave ports of the crossbar. More...

std::vector< MasterPort * >	masterPorts

PortID	defaultPortID
	Port that handles requests that don't match any of the interfaces. More...

const bool	useDefaultRange
	If true, use address range provided by default device. More...

Stats::Vector	transDist
	Stats for transaction distribution and data passing through the crossbar. More...

Stats::Vector2d	pktCount

Stats::Vector2d	pktSize

Protected Attributes inherited from ClockedObject
Enums::PwrState	_currPwrState
	To keep track of the current power state. More...

Tick	prvEvalTick

Stats::Scalar	numPwrStateTransitions

Stats::Distribution	pwrStateClkGateDist

Stats::Vector	pwrStateResidencyTicks

Protected Attributes inherited from SimObject
const SimObjectParams *	_params
	Cached copy of the object parameters. More...

Protected Attributes inherited from EventManager
EventQueue *	eventq
	A pointer to this object's event queue. More...

Additional Inherited Members
Public Types inherited from MemObject
typedef MemObjectParams	Params

Public Types inherited from ClockedObject
typedef ClockedObjectParams	Params
	Parameters of ClockedObject. More...

Public Types inherited from SimObject
typedef SimObjectParams	Params

Static Public Member Functions inherited from SimObject
static void	serializeAll (CheckpointOut &cp)
	Serialize all SimObjects in the system. More...

static SimObject *	find (const char *name)
	Find the SimObject with the given name and return a pointer to it. More...

Static Public Member Functions inherited from Serializable
static const std::string &	currentSection ()
	Get the fully-qualified name of the active section. More...

static void	serializeAll (const std::string &cpt_dir)

static void	unserializeGlobals (CheckpointIn &cp)

Static Public Attributes inherited from Serializable
static int	ckptCount = 0

static int	ckptMaxCount = 0

static int	ckptPrevCount = -1

Detailed Description

A non-coherent crossbar connects a number of non-snooping masters and slaves, and routes the request and response packets based on the address.

The request packets issued by the master connected to a non-coherent crossbar could still snoop in caches attached to a coherent crossbar, as is the case with the I/O bus and memory bus in most system configurations. No snoops will, however, reach any master on the non-coherent crossbar itself.

The non-coherent crossbar can be used as a template for modelling PCIe, and non-coherent AMBA and OCP buses, and is typically used for the I/O buses.

Definition at line 70 of file noncoherent_xbar.hh.