gem5  v22.0.0.2
Classes | Public Member Functions | Public Attributes | Private Member Functions | Private Attributes | List of all members
gem5::memory::NVMInterface Class Reference

Interface to NVM devices with media specific parameters, statistics, and functions. More...

#include <nvm_interface.hh>

Inheritance diagram for gem5::memory::NVMInterface:
gem5::memory::MemInterface gem5::memory::AbstractMemory gem5::ClockedObject gem5::SimObject gem5::Clocked gem5::EventManager gem5::Serializable gem5::Drainable gem5::statistics::Group gem5::Named

Classes

struct  NVMStats
 
class  Rank
 NVM rank class simply includes a vector of banks. More...
 

Public Member Functions

void init () override
 Initialize the NVM interface and verify parameters. More...
 
void setupRank (const uint8_t rank, const bool is_read) override
 Setup the rank based on packet received. More...
 
MemPacketdecodePacket (const PacketPtr pkt, Addr pkt_addr, unsigned int size, bool is_read, uint8_t pseudo_channel=0) override
 Address decoder to figure out physical mapping onto ranks, banks, and rows. More...
 
bool allRanksDrained () const override
 Check drain state of NVM interface. More...
 
Tick commandOffset () const override
 
bool burstReady (MemPacket *pkt) const override
 Check if a burst operation can be issued to the NVM. More...
 
bool isBusy (bool read_queue_empty, bool all_writes_nvm) override
 This function checks if ranks are busy. More...
 
std::pair< MemPacketQueue::iterator, TickchooseNextFRFCFS (MemPacketQueue &queue, Tick min_col_at) const override
 For FR-FCFS policy, find first NVM command that can issue default to first command to prepped region. More...
 
void addRankToRankDelay (Tick cmd_at) override
 Add rank to rank delay to bus timing to all NVM banks in alli ranks when access to an alternate interface is issued. More...
 
void respondEvent (uint8_t rank) override
 Following two functions are not required for nvm interface. More...
 
void checkRefreshState (uint8_t rank) override
 This function is DRAM specific. More...
 
void chooseRead (MemPacketQueue &queue) override
 Select read command to issue asynchronously. More...
 
Tick accessLatency () const override
 
bool writeRespQueueFull () const override
 Check if the write response queue has reached defined threshold. More...
 
bool readsWaitingToIssue () const override
 This function is NVM specific. More...
 
std::pair< Tick, TickdoBurstAccess (MemPacket *pkt, Tick next_burst_at, const std::vector< MemPacketQueue > &queue) override
 Actually do the burst and update stats. More...
 
void drainRanks () override
 The next three functions are DRAM-specific and will be ignored by NVM. More...
 
void suspend () override
 This function is DRAM specific. More...
 
void startup () override
 startup() is the final initialization call before simulation. More...
 
 NVMInterface (const NVMInterfaceParams &_p)
 
- Public Member Functions inherited from gem5::memory::MemInterface
void setCtrl (MemCtrl *_ctrl, unsigned int command_window, uint8_t pseudo_channel=0)
 Set a pointer to the controller and initialize interface based on controller parameters. More...
 
Addr getCtrlAddr (Addr addr)
 Get an address in a dense range which starts from 0. More...
 
uint32_t bytesPerBurst () const
 
Tick rankDelay () const
 Determine the required delay for an access to a different rank. More...
 
Tick minReadToWriteDataGap () const
 
Tick minWriteToReadDataGap () const
 
 MemInterface (const Params &_p)
 
- Public Member Functions inherited from gem5::memory::AbstractMemory
 PARAMS (AbstractMemory)
 
 AbstractMemory (const Params &p)
 
virtual ~AbstractMemory ()
 
void initState () override
 initState() is called on each SimObject when not restoring from a checkpoint. More...
 
bool isNull () const
 See if this is a null memory that should never store data and always return zero. More...
 
void setBackingStore (uint8_t *pmem_addr)
 Set the host memory backing store to be used by this memory controller. More...
 
void getBackdoor (MemBackdoorPtr &bd_ptr)
 
const std::list< LockedAddr > & getLockedAddrList () const
 Get the list of locked addresses to allow checkpointing. More...
 
void addLockedAddr (LockedAddr addr)
 Add a locked address to allow for checkpointing. More...
 
Systemsystem () const
 read the system pointer Implemented for completeness with the setter More...
 
void system (System *sys)
 Set the system pointer on this memory This can't be done via a python parameter because the system needs pointers to all the memories and the reverse would create a cycle in the object graph. More...
 
AddrRange getAddrRange () const
 Get the address range. More...
 
uint8_t * toHostAddr (Addr addr) const
 Transform a gem5 address space address into its physical counterpart in the host address space. More...
 
uint64_t size () const
 Get the memory size. More...
 
Addr start () const
 Get the start address. More...
 
bool isConfReported () const
 Should this memory be passed to the kernel and part of the OS physical memory layout. More...
 
bool isInAddrMap () const
 Some memories are used as shadow memories or should for other reasons not be part of the global address map. More...
 
bool isKvmMap () const
 When shadow memories are in use, KVM may want to make one or the other, but cannot map both into the guest address space. More...
 
void access (PacketPtr pkt)
 Perform an untimed memory access and update all the state (e.g. More...
 
void functionalAccess (PacketPtr pkt)
 Perform an untimed memory read or write without changing anything but the memory itself. 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 loadState (CheckpointIn &cp)
 loadState() is called on each SimObject when 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 PortgetPort (const std::string &if_name, PortID idx=InvalidPortID)
 Get a port with a given name and index. 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 regStats ()
 Callback to set stat parameters. More...
 
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
 

Public Attributes

uint16_t numReadsToIssue
 
- Public Attributes inherited from gem5::memory::MemInterface
const uint32_t readBufferSize
 Buffer sizes for read and write queues in the controller These are passed to the controller on instantiation Defining them here allows for buffers to be resized based on memory type / configuration. More...
 
const uint32_t writeBufferSize
 
uint32_t numWritesQueued
 NVM specific variable, but declaring it here allows treating different interfaces in a more genral way at the memory controller's end. More...
 
Tick nextBurstAt = 0
 Till when the controller must wait before issuing next RD/WR burst? More...
 
Tick nextReqTime = 0
 
uint8_t pseudoChannel
 pseudo channel number used for HBM modeling More...
 
- Public Attributes inherited from gem5::ClockedObject
PowerStatepowerState
 

Private Member Functions

void processWriteRespondEvent ()
 
void processReadReadyEvent ()
 
bool writeRespQueueEmpty () const
 Check if the write response queue is empty. More...
 

Private Attributes

const uint32_t maxPendingWrites
 NVM specific device and channel characteristics. More...
 
const uint32_t maxPendingReads
 
const bool twoCycleRdWr
 
const Tick tREAD
 NVM specific timing requirements. More...
 
const Tick tWRITE
 
const Tick tSEND
 
NVMStats stats
 
EventFunctionWrapper writeRespondEvent
 
EventFunctionWrapper readReadyEvent
 
std::vector< Rank * > ranks
 Vector of nvm ranks. More...
 
std::list< TickwriteRespQueue
 Holding queue for non-deterministic write commands, which maintains writes that have been issued but have not completed Stored seperately mostly to keep the code clean and help with events scheduling. More...
 
std::deque< TickreadReadyQueue
 
Tick nextReadAt
 Till when must we wait before issuing next read command? More...
 
uint16_t numPendingReads
 
uint16_t numReadDataReady
 

Additional Inherited Members

- Public Types inherited from gem5::memory::MemInterface
typedef MemInterfaceParams Params
 
- 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...
 
- Protected Member Functions inherited from gem5::memory::MemInterface
virtual Tick writeToReadDelay () const
 
Tick readToWriteDelay () const
 
Tick rankToRankDelay () const
 
- Protected Member Functions inherited from gem5::memory::AbstractMemory
bool checkLockedAddrList (PacketPtr pkt)
 
void trackLoadLocked (PacketPtr pkt)
 
bool writeOK (PacketPtr pkt)
 
- 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 inherited from gem5::memory::MemInterface
MemCtrlctrl
 A pointer to the parent memory controller instance. More...
 
unsigned int maxCommandsPerWindow
 Number of commands that can issue in the defined controller command window, used to verify command bandwidth. More...
 
enums::AddrMap addrMapping
 Memory controller configuration initialized based on parameter values. More...
 
const uint32_t burstSize
 General device and channel characteristics The rowsPerBank is determined based on the capacity, number of ranks and banks, the burst size, and the row buffer size. More...
 
const uint32_t deviceSize
 
const uint32_t deviceRowBufferSize
 
const uint32_t devicesPerRank
 
const uint32_t rowBufferSize
 
const uint32_t burstsPerRowBuffer
 
const uint32_t burstsPerStripe
 
const uint32_t ranksPerChannel
 
const uint32_t banksPerRank
 
uint32_t rowsPerBank
 
const GEM5_CLASS_VAR_USED Tick tCK
 General timing requirements. More...
 
const Tick tCS
 
const Tick tBURST
 
const Tick tRTW
 
const Tick tWTR
 
- Protected Attributes inherited from gem5::memory::AbstractMemory
AddrRange range
 
uint8_t * pmemAddr
 
MemBackdoor backdoor
 
const bool confTableReported
 
const bool inAddrMap
 
const bool kvmMap
 
std::list< LockedAddrlockedAddrList
 
System_system
 Pointer to the System object. More...
 
gem5::memory::AbstractMemory::MemStats stats
 
- 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...
 

Detailed Description

Interface to NVM devices with media specific parameters, statistics, and functions.

The NVMInterface includes a class for individual ranks and per rank functions.

Definition at line 64 of file nvm_interface.hh.

Constructor & Destructor Documentation

◆ NVMInterface()

gem5::memory::NVMInterface::NVMInterface ( const NVMInterfaceParams &  _p)

Definition at line 55 of file nvm_interface.cc.

References processWriteRespondEvent().

Member Function Documentation

◆ accessLatency()

Tick gem5::memory::NVMInterface::accessLatency ( ) const
inlineoverridevirtual

Implements gem5::memory::MemInterface.

Definition at line 278 of file nvm_interface.hh.

References tREAD, and tSEND.

◆ addRankToRankDelay()

void gem5::memory::NVMInterface::addRankToRankDelay ( Tick  cmd_at)
overridevirtual

Add rank to rank delay to bus timing to all NVM banks in alli ranks when access to an alternate interface is issued.

param cmd_at Time of current command used as starting point for addition of rank-to-rank delay

Implements gem5::memory::MemInterface.

Definition at line 588 of file nvm_interface.cc.

References gem5::memory::MemInterface::banksPerRank, gem5::ArmISA::i, gem5::ArmISA::n, ranks, and gem5::memory::MemInterface::rankToRankDelay().

Referenced by gem5::memory::HeteroMemCtrl::doBurstAccess().

◆ allRanksDrained()

bool gem5::memory::NVMInterface::allRanksDrained ( ) const
inlineoverridevirtual

Check drain state of NVM interface.

Returns
true if write response queue is empty

Implements gem5::memory::MemInterface.

Definition at line 213 of file nvm_interface.hh.

References writeRespQueueEmpty().

Referenced by gem5::memory::HeteroMemCtrl::allIntfDrained().

◆ burstReady()

bool gem5::memory::NVMInterface::burstReady ( MemPacket pkt) const
overridevirtual

Check if a burst operation can be issued to the NVM.

Parameters
Returntrue if RD/WR can issue for reads, also verfy that ready count has been updated to a non-zero value to account for race conditions between events

Implements gem5::memory::MemInterface.

Definition at line 404 of file nvm_interface.cc.

References gem5::memory::MemInterface::ctrl, gem5::curTick(), gem5::memory::MemCtrl::inReadBusState(), gem5::memory::MemPacket::isRead(), numReadDataReady, gem5::memory::MemPacket::readyTime, and writeRespQueueFull().

Referenced by chooseNextFRFCFS().

◆ checkRefreshState()

void gem5::memory::NVMInterface::checkRefreshState ( uint8_t  rank)
inlineoverridevirtual

This function is DRAM specific.

Reimplemented from gem5::memory::MemInterface.

Definition at line 268 of file nvm_interface.hh.

◆ chooseNextFRFCFS()

std::pair< MemPacketQueue::iterator, Tick > gem5::memory::NVMInterface::chooseNextFRFCFS ( MemPacketQueue queue,
Tick  min_col_at 
) const
overridevirtual

For FR-FCFS policy, find first NVM command that can issue default to first command to prepped region.

Parameters
queueQueued requests to consider
min_col_atMinimum tick for 'seamless' issue
Returns
an iterator to the selected packet, else queue.end()
the tick when the packet selected will issue

Implements gem5::memory::MemInterface.

Definition at line 208 of file nvm_interface.cc.

References gem5::memory::MemPacket::bank, burstReady(), DPRINTF, gem5::ArmISA::i, gem5::memory::MemPacket::isDram(), gem5::memory::MemPacket::isRead(), gem5::MaxTick, gem5::memory::MemPacket::rank, ranks, gem5::memory::MemInterface::Bank::rdAllowedAt, and gem5::memory::MemInterface::Bank::wrAllowedAt.

◆ chooseRead()

void gem5::memory::NVMInterface::chooseRead ( MemPacketQueue queue)
overridevirtual

◆ commandOffset()

Tick gem5::memory::NVMInterface::commandOffset ( ) const
inlineoverridevirtual

Implements gem5::memory::MemInterface.

Definition at line 218 of file nvm_interface.hh.

References gem5::memory::MemInterface::tBURST.

◆ decodePacket()

MemPacket * gem5::memory::NVMInterface::decodePacket ( const PacketPtr  pkt,
Addr  pkt_addr,
unsigned int  size,
bool  is_read,
uint8_t  pseudo_channel = 0 
)
overridevirtual

Address decoder to figure out physical mapping onto ranks, banks, and rows.

This function is called multiple times on the same system packet if the pakcet is larger than burst of the memory. The pkt_addr is used for the offset within the packet.

Parameters
pktThe packet from the outside world
pkt_addrThe starting address of the packet
sizeThe size of the packet in bytes
is_readIs the request for a read or a write to memory
pseudo_channelpseudo channel number of the packet
Returns
A MemPacket pointer with the decoded information

Reimplemented from gem5::memory::MemInterface.

Definition at line 122 of file nvm_interface.cc.

References gem5::X86ISA::addr, gem5::memory::MemInterface::addrMapping, gem5::memory::MemInterface::banksPerRank, gem5::memory::MemInterface::burstSize, gem5::memory::MemInterface::burstsPerRowBuffer, gem5::memory::MemInterface::burstsPerStripe, DPRINTF, gem5::memory::MemInterface::getCtrlAddr(), gem5::memory::MemInterface::Bank::NO_ROW, panic, gem5::memory::MemInterface::ranksPerChannel, gem5::memory::MemInterface::rowsPerBank, and gem5::memory::AbstractMemory::size().

◆ doBurstAccess()

std::pair< Tick, Tick > gem5::memory::NVMInterface::doBurstAccess ( MemPacket pkt,
Tick  next_burst_at,
const std::vector< MemPacketQueue > &  queue 
)
overridevirtual

Actually do the burst and update stats.

Parameters
pktThe packet created from the outside world pkt
next_burst_atMinimum bus timing requirement from controller
Returns
pair, tick when current burst is issued and tick when next burst can issue

Implements gem5::memory::MemInterface.

Definition at line 413 of file nvm_interface.cc.

References gem5::memory::MemInterface::Bank::actAllowedAt, gem5::memory::MemPacket::addr, gem5::memory::MemInterface::Bank::bank, gem5::memory::MemPacket::bank, gem5::memory::MemPacket::bankId, gem5::memory::MemInterface::banksPerRank, gem5::memory::MemInterface::burstSize, gem5::memory::MemInterface::Bank::bytesAccessed, gem5::memory::NVMInterface::NVMStats::bytesPerBank, gem5::memory::NVMInterface::NVMStats::bytesRead, gem5::memory::NVMInterface::NVMStats::bytesWritten, gem5::memory::MemInterface::ctrl, gem5::curTick(), DPRINTF, gem5::memory::MemPacket::entryTime, gem5::ArmISA::i, gem5::memory::MemPacket::isRead(), gem5::memory::MemInterface::maxCommandsPerWindow, gem5::ArmISA::n, numPendingReads, numReadDataReady, gem5::memory::MemInterface::numWritesQueued, gem5::memory::MemInterface::Bank::openRow, gem5::memory::NVMInterface::NVMStats::pendingReads, gem5::memory::NVMInterface::NVMStats::perBankRdBursts, gem5::memory::NVMInterface::NVMStats::perBankWrBursts, gem5::memory::MemPacket::rank, ranks, gem5::memory::MemInterface::rankToRankDelay(), gem5::memory::MemInterface::Bank::rdAllowedAt, gem5::memory::NVMInterface::NVMStats::readBursts, gem5::memory::MemInterface::readToWriteDelay(), gem5::memory::MemPacket::readyTime, gem5::EventManager::reschedule(), gem5::memory::MemPacket::row, gem5::statistics::DistBase< Derived, Stor >::sample(), gem5::EventManager::schedule(), gem5::Event::scheduled(), stats, gem5::memory::MemInterface::tBURST, gem5::memory::MemInterface::tCK, gem5::memory::NVMInterface::NVMStats::totBusLat, gem5::memory::NVMInterface::NVMStats::totMemAccLat, gem5::memory::NVMInterface::NVMStats::totQLat, tSEND, twoCycleRdWr, tWRITE, gem5::memory::MemCtrl::verifyMultiCmd(), gem5::memory::MemCtrl::verifySingleCmd(), gem5::Event::when(), gem5::memory::MemInterface::Bank::wrAllowedAt, gem5::memory::NVMInterface::NVMStats::writeBursts, writeRespondEvent, writeRespQueue, writeRespQueueEmpty(), writeRespQueueFull(), and gem5::memory::MemInterface::writeToReadDelay().

◆ drainRanks()

void gem5::memory::NVMInterface::drainRanks ( )
inlineoverridevirtual

The next three functions are DRAM-specific and will be ignored by NVM.

Reimplemented from gem5::memory::MemInterface.

Definition at line 313 of file nvm_interface.hh.

◆ init()

void gem5::memory::NVMInterface::init ( )
overridevirtual

Initialize the NVM interface and verify parameters.

Reimplemented from gem5::SimObject.

Definition at line 105 of file nvm_interface.cc.

References gem5::SimObject::init().

◆ isBusy()

bool gem5::memory::NVMInterface::isBusy ( bool  read_queue_empty,
bool  all_writes_nvm 
)
overridevirtual

This function checks if ranks are busy.

This state is true when either: 1) There is no command with read data ready to transmit or 2) The NVM inteface has reached the maximum number of outstanding writes commands.

Parameters
read_queue_emptyThere are no read queued
all_writes_nvmAll writes in queue are for NVM interface
Returns
true of NVM is busy

Implements gem5::memory::MemInterface.

Definition at line 605 of file nvm_interface.cc.

References gem5::memory::MemInterface::ctrl, DPRINTF, gem5::memory::MemCtrl::inReadBusState(), numReadDataReady, and writeRespQueueFull().

Referenced by gem5::memory::HeteroMemCtrl::memBusy().

◆ processReadReadyEvent()

void gem5::memory::NVMInterface::processReadReadyEvent ( )
private

◆ processWriteRespondEvent()

void gem5::memory::NVMInterface::processWriteRespondEvent ( )
private

◆ readsWaitingToIssue()

bool gem5::memory::NVMInterface::readsWaitingToIssue ( ) const
inlineoverridevirtual

This function is NVM specific.

Reimplemented from gem5::memory::MemInterface.

Definition at line 292 of file nvm_interface.hh.

References maxPendingReads, numPendingReads, and numReadsToIssue.

◆ respondEvent()

void gem5::memory::NVMInterface::respondEvent ( uint8_t  rank)
inlineoverridevirtual

Following two functions are not required for nvm interface.

Reimplemented from gem5::memory::MemInterface.

Definition at line 266 of file nvm_interface.hh.

◆ setupRank()

void gem5::memory::NVMInterface::setupRank ( const uint8_t  rank,
const bool  is_read 
)
overridevirtual

Setup the rank based on packet received.

Parameters
integervalue of rank to be setup. used to index ranks vector
arewe setting up rank for read or write packet?

Implements gem5::memory::MemInterface.

Definition at line 110 of file nvm_interface.cc.

References numReadsToIssue, and gem5::memory::MemInterface::numWritesQueued.

◆ startup()

void gem5::memory::NVMInterface::startup ( )
inlineoverridevirtual

startup() is the final initialization call before simulation.

All state is initialized (including unserialized state, if any, such as the curTick() value), so this is the appropriate place to schedule initial event(s) for objects that need them.

Reimplemented from gem5::SimObject.

Definition at line 315 of file nvm_interface.hh.

◆ suspend()

void gem5::memory::NVMInterface::suspend ( )
inlineoverridevirtual

This function is DRAM specific.

Reimplemented from gem5::memory::MemInterface.

Definition at line 314 of file nvm_interface.hh.

◆ writeRespQueueEmpty()

bool gem5::memory::NVMInterface::writeRespQueueEmpty ( ) const
inlineprivate

Check if the write response queue is empty.

Parameters
Returntrue if empty

Definition at line 174 of file nvm_interface.hh.

References writeRespQueue.

Referenced by allRanksDrained(), and doBurstAccess().

◆ writeRespQueueFull()

bool gem5::memory::NVMInterface::writeRespQueueFull ( ) const
inlineoverridevirtual

Check if the write response queue has reached defined threshold.

Parameters
Returntrue if full

Reimplemented from gem5::memory::MemInterface.

Definition at line 286 of file nvm_interface.hh.

References maxPendingWrites, and writeRespQueue.

Referenced by burstReady(), doBurstAccess(), and isBusy().

Member Data Documentation

◆ maxPendingReads

const uint32_t gem5::memory::NVMInterface::maxPendingReads
private

Definition at line 93 of file nvm_interface.hh.

Referenced by chooseRead(), and readsWaitingToIssue().

◆ maxPendingWrites

const uint32_t gem5::memory::NVMInterface::maxPendingWrites
private

NVM specific device and channel characteristics.

Definition at line 92 of file nvm_interface.hh.

Referenced by writeRespQueueFull().

◆ nextReadAt

Tick gem5::memory::NVMInterface::nextReadAt
private

Till when must we wait before issuing next read command?

Definition at line 179 of file nvm_interface.hh.

Referenced by chooseRead().

◆ numPendingReads

uint16_t gem5::memory::NVMInterface::numPendingReads
private

◆ numReadDataReady

uint16_t gem5::memory::NVMInterface::numReadDataReady
private

Definition at line 184 of file nvm_interface.hh.

Referenced by burstReady(), doBurstAccess(), isBusy(), and processReadReadyEvent().

◆ numReadsToIssue

uint16_t gem5::memory::NVMInterface::numReadsToIssue

Definition at line 188 of file nvm_interface.hh.

Referenced by chooseRead(), readsWaitingToIssue(), and setupRank().

◆ ranks

std::vector<Rank*> gem5::memory::NVMInterface::ranks
private

Vector of nvm ranks.

Definition at line 155 of file nvm_interface.hh.

Referenced by addRankToRankDelay(), chooseNextFRFCFS(), chooseRead(), and doBurstAccess().

◆ readReadyEvent

EventFunctionWrapper gem5::memory::NVMInterface::readReadyEvent
private

Definition at line 150 of file nvm_interface.hh.

Referenced by chooseRead(), and processReadReadyEvent().

◆ readReadyQueue

std::deque<Tick> gem5::memory::NVMInterface::readReadyQueue
private

Definition at line 167 of file nvm_interface.hh.

Referenced by chooseRead(), and processReadReadyEvent().

◆ stats

NVMStats gem5::memory::NVMInterface::stats
private

Definition at line 144 of file nvm_interface.hh.

Referenced by chooseRead(), doBurstAccess(), and processWriteRespondEvent().

◆ tREAD

const Tick gem5::memory::NVMInterface::tREAD
private

NVM specific timing requirements.

Definition at line 99 of file nvm_interface.hh.

Referenced by accessLatency(), and chooseRead().

◆ tSEND

const Tick gem5::memory::NVMInterface::tSEND
private

Definition at line 101 of file nvm_interface.hh.

Referenced by accessLatency(), and doBurstAccess().

◆ twoCycleRdWr

const bool gem5::memory::NVMInterface::twoCycleRdWr
private

Definition at line 94 of file nvm_interface.hh.

Referenced by chooseRead(), and doBurstAccess().

◆ tWRITE

const Tick gem5::memory::NVMInterface::tWRITE
private

Definition at line 100 of file nvm_interface.hh.

Referenced by doBurstAccess().

◆ writeRespondEvent

EventFunctionWrapper gem5::memory::NVMInterface::writeRespondEvent
private

Definition at line 147 of file nvm_interface.hh.

Referenced by doBurstAccess(), and processWriteRespondEvent().

◆ writeRespQueue

std::list<Tick> gem5::memory::NVMInterface::writeRespQueue
private

Holding queue for non-deterministic write commands, which maintains writes that have been issued but have not completed Stored seperately mostly to keep the code clean and help with events scheduling.

This mimics a buffer on the media controller and therefore is not added to the main write queue for sizing

Definition at line 165 of file nvm_interface.hh.

Referenced by doBurstAccess(), processWriteRespondEvent(), writeRespQueueEmpty(), and writeRespQueueFull().


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

Generated on Thu Jul 28 2022 13:34:08 for gem5 by doxygen 1.8.17