gem5  v21.1.0.2
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gem5::NoncoherentXBar Class Reference

A non-coherent crossbar connects a number of non-snooping memory-side ports and cpu_sides, and routes the request and response packets based on the address. More...

#include <noncoherent_xbar.hh>

Inheritance diagram for gem5::NoncoherentXBar:
gem5::BaseXBar gem5::ClockedObject gem5::SimObject gem5::Clocked gem5::EventManager gem5::Serializable gem5::Drainable gem5::statistics::Group gem5::Named gem5::HMCController

Classes

class  NoncoherentXBarRequestPort
 Declaration of the crossbar memory-side port type, one will be instantiated for each of the CPU-side ports connecting to the crossbar. More...
 
class  NoncoherentXBarResponsePort
 Declaration of the non-coherent crossbar CPU-side port type, one will be instantiated for each of the memory-side ports connecting to the crossbar. More...
 

Public Member Functions

 NoncoherentXBar (const NoncoherentXBarParams &p)
 
virtual ~NoncoherentXBar ()
 
- Public Member Functions inherited from gem5::BaseXBar
virtual ~BaseXBar ()
 
PortgetPort (const std::string &if_name, PortID idx=InvalidPortID) override
 A function used to return the port associated with this object. More...
 
void regStats () override
 Callback to set stat parameters. More...
 
- Public Member Functions inherited from gem5::ClockedObject
 ClockedObject (const ClockedObjectParams &p)
 
void serialize (CheckpointOut &cp) const override
 Serialize an object. More...
 
void unserialize (CheckpointIn &cp) override
 Unserialize an object. More...
 
- Public Member Functions inherited from gem5::SimObject
const Paramsparams () const
 
 SimObject (const Params &p)
 
virtual ~SimObject ()
 
virtual void init ()
 init() is called after all C++ SimObjects have been created and all ports are connected. More...
 
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 regProbePoints ()
 Register probe points for this object. More...
 
virtual void regProbeListeners ()
 Register probe listeners for this object. More...
 
ProbeManagergetProbeManager ()
 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 gem5::EventManager
EventQueueeventQueue () 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)
 This function is not needed by the usual gem5 event loop but may be necessary in derived EventQueues which host gem5 on other schedulers. More...
 
void setCurTick (Tick newVal)
 
 EventManager (EventManager &em)
 Event manger manages events in the event queue. More...
 
 EventManager (EventManager *em)
 
 EventManager (EventQueue *eq)
 
- Public Member Functions inherited from gem5::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 gem5::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 gem5::statistics::Group
 Group (Group *parent, const char *name=nullptr)
 Construct a new statistics group. More...
 
virtual ~Group ()
 
virtual void resetStats ()
 Callback to reset stats. More...
 
virtual void preDumpStats ()
 Callback before stats are dumped. More...
 
void addStat (statistics::Info *info)
 Register a stat with this group. More...
 
const std::map< std::string, Group * > & getStatGroups () const
 Get all child groups associated with this object. More...
 
const std::vector< Info * > & getStats () const
 Get all stats associated with this object. More...
 
void addStatGroup (const char *name, Group *block)
 Add a stat block as a child of this block. More...
 
const InforesolveStat (std::string name) const
 Resolve a stat by its name within this group. More...
 
void mergeStatGroup (Group *block)
 Merge the contents (stats & children) of a block to this block. More...
 
 Group ()=delete
 
 Group (const Group &)=delete
 
Groupoperator= (const Group &)=delete
 
- Public Member Functions inherited from gem5::Named
 Named (const std::string &name_)
 
virtual ~Named ()=default
 
virtual std::string name () const
 
- Public Member Functions inherited from gem5::Clocked
void updateClockPeriod ()
 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
 

Protected Member Functions

virtual bool recvTimingReq (PacketPtr pkt, PortID cpu_side_port_id)
 
virtual bool recvTimingResp (PacketPtr pkt, PortID mem_side_port_id)
 
void recvReqRetry (PortID mem_side_port_id)
 
Tick recvAtomicBackdoor (PacketPtr pkt, PortID cpu_side_port_id, MemBackdoorPtr *backdoor=nullptr)
 
void recvFunctional (PacketPtr pkt, PortID cpu_side_port_id)
 
- Protected Member Functions inherited from gem5::BaseXBar
virtual void recvRangeChange (PortID mem_side_port_id)
 Function called by the port when the crossbar is recieving a range change. More...
 
PortID findPort (AddrRange addr_range)
 Find which port connected to this crossbar (if any) should be given a packet with this address range. More...
 
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 gem5::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 gem5::Clocked
 Clocked (ClockDomain &clk_domain)
 Create a clocked object and set the clock domain based on the parameters. More...
 
 Clocked (Clocked &)=delete
 
Clockedoperator= (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...
 
virtual void clockPeriodUpdated ()
 A hook subclasses can implement so they can do any extra work that's needed when the clock rate is changed. 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 gem5::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
 
const Cycles responseLatency
 
const Cycles headerLatency
 Cycles the layer is occupied processing the packet header. More...
 
const uint32_t width
 the width of the xbar in bytes More...
 
AddrRangeMap< PortID, 3 > portMap
 
std::unordered_map< RequestPtr, PortIDrouteTo
 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
 
std::vector< bool > gotAddrRanges
 Remember for each of the memory-side ports of the crossbar if we got an address range from the connected CPU-side ports. More...
 
bool gotAllAddrRanges
 
std::vector< QueuedResponsePort * > cpuSidePorts
 The memory-side ports and CPU-side ports of the crossbar. More...
 
std::vector< RequestPort * > memSidePorts
 
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...
 
statistics::Vector transDist
 Stats for transaction distribution and data passing through the crossbar. More...
 
statistics::Vector2d pktCount
 
statistics::Vector2d pktSize
 
- Protected Attributes inherited from gem5::SimObject
const SimObjectParams & _params
 Cached copy of the object parameters. More...
 
- Protected Attributes inherited from gem5::EventManager
EventQueueeventq
 A pointer to this object's event queue. More...
 

Additional Inherited Members

- Public Types inherited from gem5::ClockedObject
using Params = ClockedObjectParams
 Parameters of ClockedObject. More...
 
- Public Types inherited from gem5::SimObject
typedef SimObjectParams Params
 
- Static Public Member Functions inherited from gem5::SimObject
static void serializeAll (const std::string &cpt_dir)
 Create a checkpoint by serializing all SimObjects in the system. More...
 
static SimObjectfind (const char *name)
 Find the SimObject with the given name and return a pointer to it. More...
 
static void setSimObjectResolver (SimObjectResolver *resolver)
 There is a single object name resolver, and it is only set when simulation is restoring from checkpoints. More...
 
static SimObjectResolvergetSimObjectResolver ()
 There is a single object name resolver, and it is only set when simulation is restoring from checkpoints. More...
 
- Static Public Member Functions inherited from gem5::Serializable
static const std::string & currentSection ()
 Gets the fully-qualified name of the active section. More...
 
static void generateCheckpointOut (const std::string &cpt_dir, std::ofstream &outstream)
 Generate a checkpoint file so that the serialization can be routed to it. More...
 
- Public Attributes inherited from gem5::ClockedObject
PowerStatepowerState
 

Detailed Description

A non-coherent crossbar connects a number of non-snooping memory-side ports and cpu_sides, and routes the request and response packets based on the address.

The request packets issued by the memory-side port 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 memory-side port 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 68 of file noncoherent_xbar.hh.

Constructor & Destructor Documentation

◆ NoncoherentXBar()

gem5::NoncoherentXBar::NoncoherentXBar ( const NoncoherentXBarParams &  p)

◆ ~NoncoherentXBar()

gem5::NoncoherentXBar::~NoncoherentXBar ( )
virtual

Definition at line 93 of file noncoherent_xbar.cc.

References gem5::MipsISA::l, reqLayers, and respLayers.

Member Function Documentation

◆ recvAtomicBackdoor()

Tick gem5::NoncoherentXBar::recvAtomicBackdoor ( PacketPtr  pkt,
PortID  cpu_side_port_id,
MemBackdoorPtr backdoor = nullptr 
)
protected

◆ recvFunctional()

void gem5::NoncoherentXBar::recvFunctional ( PacketPtr  pkt,
PortID  cpu_side_port_id 
)
protected

◆ recvReqRetry()

void gem5::NoncoherentXBar::recvReqRetry ( PortID  mem_side_port_id)
protected

◆ recvTimingReq()

bool gem5::NoncoherentXBar::recvTimingReq ( PacketPtr  pkt,
PortID  cpu_side_port_id 
)
protectedvirtual

◆ recvTimingResp()

bool gem5::NoncoherentXBar::recvTimingResp ( PacketPtr  pkt,
PortID  mem_side_port_id 
)
protectedvirtual

Member Data Documentation

◆ reqLayers

std::vector<ReqLayer*> gem5::NoncoherentXBar::reqLayers
protected

Declare the layers of this crossbar, one vector for requests and one for responses.

Definition at line 77 of file noncoherent_xbar.hh.

Referenced by NoncoherentXBar(), recvReqRetry(), gem5::HMCController::recvTimingReq(), recvTimingReq(), and ~NoncoherentXBar().

◆ respLayers

std::vector<RespLayer*> gem5::NoncoherentXBar::respLayers
protected

Definition at line 78 of file noncoherent_xbar.hh.

Referenced by NoncoherentXBar(), recvTimingResp(), and ~NoncoherentXBar().


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

Generated on Tue Sep 21 2021 12:27:48 for gem5 by doxygen 1.8.17