/* * Copyright (c) 2011-2013, 2016-2019 ARM Limited * Copyright (c) 2013 Advanced Micro Devices, Inc. * 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. * * Copyright (c) 2004-2005 The Regents of The University of Michigan * Copyright (c) 2011 Regents of the University of California * 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. * * Authors: Kevin Lim * Korey Sewell * Rick Strong */ #ifndef __CPU_O3_CPU_HH__ #define __CPU_O3_CPU_HH__ #include #include #include #include #include #include "arch/generic/types.hh" #include "arch/types.hh" #include "base/statistics.hh" #include "config/the_isa.hh" #include "cpu/o3/comm.hh" #include "cpu/o3/cpu_policy.hh" #include "cpu/o3/scoreboard.hh" #include "cpu/o3/thread_state.hh" #include "cpu/activity.hh" #include "cpu/base.hh" #include "cpu/simple_thread.hh" #include "cpu/timebuf.hh" //#include "cpu/o3/thread_context.hh" #include "params/DerivO3CPU.hh" #include "sim/process.hh" template class Checker; class ThreadContext; template class O3ThreadContext; class Checkpoint; class MemObject; class Process; struct BaseCPUParams; class BaseO3CPU : public BaseCPU { //Stuff that's pretty ISA independent will go here. public: BaseO3CPU(BaseCPUParams *params); void regStats(); }; /** * FullO3CPU class, has each of the stages (fetch through commit) * within it, as well as all of the time buffers between stages. The * tick() function for the CPU is defined here. */ template class FullO3CPU : public BaseO3CPU { public: // Typedefs from the Impl here. typedef typename Impl::CPUPol CPUPolicy; typedef typename Impl::DynInstPtr DynInstPtr; typedef typename Impl::O3CPU O3CPU; using VecElem = TheISA::VecElem; using VecRegContainer = TheISA::VecRegContainer; typedef O3ThreadState ImplState; typedef O3ThreadState Thread; typedef typename std::list::iterator ListIt; friend class O3ThreadContext; public: enum Status { Running, Idle, Halted, Blocked, SwitchedOut }; BaseTLB *itb; BaseTLB *dtb; using LSQRequest = typename LSQ::LSQRequest; /** Overall CPU status. */ Status _status; private: /** * IcachePort class for instruction fetch. */ class IcachePort : public MasterPort { protected: /** Pointer to fetch. */ DefaultFetch *fetch; public: /** Default constructor. */ IcachePort(DefaultFetch *_fetch, FullO3CPU* _cpu) : MasterPort(_cpu->name() + ".icache_port", _cpu), fetch(_fetch) { } protected: /** Timing version of receive. Handles setting fetch to the * proper status to start fetching. */ virtual bool recvTimingResp(PacketPtr pkt); /** Handles doing a retry of a failed fetch. */ virtual void recvReqRetry(); }; /** * DcachePort class for the load/store queue. */ class DcachePort : public MasterPort { protected: /** Pointer to LSQ. */ LSQ *lsq; FullO3CPU *cpu; public: /** Default constructor. */ DcachePort(LSQ *_lsq, FullO3CPU* _cpu) : MasterPort(_cpu->name() + ".dcache_port", _cpu), lsq(_lsq), cpu(_cpu) { } protected: /** Timing version of receive. Handles writing back and * completing the load or store that has returned from * memory. */ virtual bool recvTimingResp(PacketPtr pkt); virtual void recvTimingSnoopReq(PacketPtr pkt); virtual void recvFunctionalSnoop(PacketPtr pkt) { // @todo: Is there a need for potential invalidation here? } /** Handles doing a retry of the previous send. */ virtual void recvReqRetry(); /** * As this CPU requires snooping to maintain the load store queue * change the behaviour from the base CPU port. * * @return true since we have to snoop */ virtual bool isSnooping() const { return true; } }; /** The tick event used for scheduling CPU ticks. */ EventFunctionWrapper tickEvent; /** Schedule tick event, regardless of its current state. */ void scheduleTickEvent(Cycles delay) { if (tickEvent.squashed()) reschedule(tickEvent, clockEdge(delay)); else if (!tickEvent.scheduled()) schedule(tickEvent, clockEdge(delay)); } /** Unschedule tick event, regardless of its current state. */ void unscheduleTickEvent() { if (tickEvent.scheduled()) tickEvent.squash(); } /** * Check if the pipeline has drained and signal drain done. * * This method checks if a drain has been requested and if the CPU * has drained successfully (i.e., there are no instructions in * the pipeline). If the CPU has drained, it deschedules the tick * event and signals the drain manager. * * @return False if a drain hasn't been requested or the CPU * hasn't drained, true otherwise. */ bool tryDrain(); /** * Perform sanity checks after a drain. * * This method is called from drain() when it has determined that * the CPU is fully drained when gem5 is compiled with the NDEBUG * macro undefined. The intention of this method is to do more * extensive tests than the isDrained() method to weed out any * draining bugs. */ void drainSanityCheck() const; /** Check if a system is in a drained state. */ bool isDrained() const; public: /** Constructs a CPU with the given parameters. */ FullO3CPU(DerivO3CPUParams *params); /** Destructor. */ ~FullO3CPU(); /** Registers statistics. */ void regStats() override; ProbePointArg *ppInstAccessComplete; ProbePointArg > *ppDataAccessComplete; /** Register probe points. */ void regProbePoints() override; void demapPage(Addr vaddr, uint64_t asn) { this->itb->demapPage(vaddr, asn); this->dtb->demapPage(vaddr, asn); } void demapInstPage(Addr vaddr, uint64_t asn) { this->itb->demapPage(vaddr, asn); } void demapDataPage(Addr vaddr, uint64_t asn) { this->dtb->demapPage(vaddr, asn); } /** Ticks CPU, calling tick() on each stage, and checking the overall * activity to see if the CPU should deschedule itself. */ void tick(); /** Initialize the CPU */ void init() override; void startup() override; /** Returns the Number of Active Threads in the CPU */ int numActiveThreads() { return activeThreads.size(); } /** Add Thread to Active Threads List */ void activateThread(ThreadID tid); /** Remove Thread from Active Threads List */ void deactivateThread(ThreadID tid); /** Setup CPU to insert a thread's context */ void insertThread(ThreadID tid); /** Remove all of a thread's context from CPU */ void removeThread(ThreadID tid); /** Count the Total Instructions Committed in the CPU. */ Counter totalInsts() const override; /** Count the Total Ops (including micro ops) committed in the CPU. */ Counter totalOps() const override; /** Add Thread to Active Threads List. */ void activateContext(ThreadID tid) override; /** Remove Thread from Active Threads List */ void suspendContext(ThreadID tid) override; /** Remove Thread from Active Threads List && * Remove Thread Context from CPU. */ void haltContext(ThreadID tid) override; /** Update The Order In Which We Process Threads. */ void updateThreadPriority(); /** Is the CPU draining? */ bool isDraining() const { return drainState() == DrainState::Draining; } void serializeThread(CheckpointOut &cp, ThreadID tid) const override; void unserializeThread(CheckpointIn &cp, ThreadID tid) override; public: /** Executes a syscall. * @todo: Determine if this needs to be virtual. */ void syscall(int64_t callnum, ThreadID tid, Fault *fault); /** Starts draining the CPU's pipeline of all instructions in * order to stop all memory accesses. */ DrainState drain() override; /** Resumes execution after a drain. */ void drainResume() override; /** * Commit has reached a safe point to drain a thread. * * Commit calls this method to inform the pipeline that it has * reached a point where it is not executed microcode and is about * to squash uncommitted instructions to fully drain the pipeline. */ void commitDrained(ThreadID tid); /** Switches out this CPU. */ void switchOut() override; /** Takes over from another CPU. */ void takeOverFrom(BaseCPU *oldCPU) override; void verifyMemoryMode() const override; /** Get the current instruction sequence number, and increment it. */ InstSeqNum getAndIncrementInstSeq() { return globalSeqNum++; } /** Traps to handle given fault. */ void trap(const Fault &fault, ThreadID tid, const StaticInstPtr &inst); /** HW return from error interrupt. */ Fault hwrei(ThreadID tid); bool simPalCheck(int palFunc, ThreadID tid); /** Check if a change in renaming is needed for vector registers. * The vecMode variable is updated and propagated to rename maps. * * @param tid ThreadID * @param freelist list of free registers */ void switchRenameMode(ThreadID tid, UnifiedFreeList* freelist); /** Returns the Fault for any valid interrupt. */ Fault getInterrupts(); /** Processes any an interrupt fault. */ void processInterrupts(const Fault &interrupt); /** Halts the CPU. */ void halt() { panic("Halt not implemented!\n"); } /** Register accessors. Index refers to the physical register index. */ /** Reads a miscellaneous register. */ RegVal readMiscRegNoEffect(int misc_reg, ThreadID tid) const; /** Reads a misc. register, including any side effects the read * might have as defined by the architecture. */ RegVal readMiscReg(int misc_reg, ThreadID tid); /** Sets a miscellaneous register. */ void setMiscRegNoEffect(int misc_reg, RegVal val, ThreadID tid); /** Sets a misc. register, including any side effects the write * might have as defined by the architecture. */ void setMiscReg(int misc_reg, RegVal val, ThreadID tid); RegVal readIntReg(PhysRegIdPtr phys_reg); RegVal readFloatRegBits(PhysRegIdPtr phys_reg); const VecRegContainer& readVecReg(PhysRegIdPtr reg_idx) const; /** * Read physical vector register for modification. */ VecRegContainer& getWritableVecReg(PhysRegIdPtr reg_idx); /** Returns current vector renaming mode */ Enums::VecRegRenameMode vecRenameMode() const { return vecMode; } /** Sets the current vector renaming mode */ void vecRenameMode(Enums::VecRegRenameMode vec_mode) { vecMode = vec_mode; } /** * Read physical vector register lane */ template VecLaneT readVecLane(PhysRegIdPtr phys_reg) const { vecRegfileReads++; return regFile.readVecLane(phys_reg); } /** * Read physical vector register lane */ template VecLaneT readVecLane(PhysRegIdPtr phys_reg) const { vecRegfileReads++; return regFile.readVecLane(phys_reg); } /** Write a lane of the destination vector register. */ template void setVecLane(PhysRegIdPtr phys_reg, const LD& val) { vecRegfileWrites++; return regFile.setVecLane(phys_reg, val); } const VecElem& readVecElem(PhysRegIdPtr reg_idx) const; TheISA::CCReg readCCReg(PhysRegIdPtr phys_reg); void setIntReg(PhysRegIdPtr phys_reg, RegVal val); void setFloatRegBits(PhysRegIdPtr phys_reg, RegVal val); void setVecReg(PhysRegIdPtr reg_idx, const VecRegContainer& val); void setVecElem(PhysRegIdPtr reg_idx, const VecElem& val); void setCCReg(PhysRegIdPtr phys_reg, TheISA::CCReg val); RegVal readArchIntReg(int reg_idx, ThreadID tid); RegVal readArchFloatRegBits(int reg_idx, ThreadID tid); const VecRegContainer& readArchVecReg(int reg_idx, ThreadID tid) const; /** Read architectural vector register for modification. */ VecRegContainer& getWritableArchVecReg(int reg_idx, ThreadID tid); /** Read architectural vector register lane. */ template VecLaneT readArchVecLane(int reg_idx, int lId, ThreadID tid) const { PhysRegIdPtr phys_reg = commitRenameMap[tid].lookup( RegId(VecRegClass, reg_idx)); return readVecLane(phys_reg); } /** Write a lane of the destination vector register. */ template void setArchVecLane(int reg_idx, int lId, ThreadID tid, const LD& val) { PhysRegIdPtr phys_reg = commitRenameMap[tid].lookup( RegId(VecRegClass, reg_idx)); setVecLane(phys_reg, val); } const VecElem& readArchVecElem(const RegIndex& reg_idx, const ElemIndex& ldx, ThreadID tid) const; TheISA::CCReg readArchCCReg(int reg_idx, ThreadID tid); /** Architectural register accessors. Looks up in the commit * rename table to obtain the true physical index of the * architected register first, then accesses that physical * register. */ void setArchIntReg(int reg_idx, RegVal val, ThreadID tid); void setArchFloatRegBits(int reg_idx, RegVal val, ThreadID tid); void setArchVecReg(int reg_idx, const VecRegContainer& val, ThreadID tid); void setArchVecElem(const RegIndex& reg_idx, const ElemIndex& ldx, const VecElem& val, ThreadID tid); void setArchCCReg(int reg_idx, TheISA::CCReg val, ThreadID tid); /** Sets the commit PC state of a specific thread. */ void pcState(const TheISA::PCState &newPCState, ThreadID tid); /** Reads the commit PC state of a specific thread. */ TheISA::PCState pcState(ThreadID tid); /** Reads the commit PC of a specific thread. */ Addr instAddr(ThreadID tid); /** Reads the commit micro PC of a specific thread. */ MicroPC microPC(ThreadID tid); /** Reads the next PC of a specific thread. */ Addr nextInstAddr(ThreadID tid); /** Initiates a squash of all in-flight instructions for a given * thread. The source of the squash is an external update of * state through the TC. */ void squashFromTC(ThreadID tid); /** Function to add instruction onto the head of the list of the * instructions. Used when new instructions are fetched. */ ListIt addInst(const DynInstPtr &inst); /** Function to tell the CPU that an instruction has completed. */ void instDone(ThreadID tid, const DynInstPtr &inst); /** Remove an instruction from the front end of the list. There's * no restriction on location of the instruction. */ void removeFrontInst(const DynInstPtr &inst); /** Remove all instructions that are not currently in the ROB. * There's also an option to not squash delay slot instructions.*/ void removeInstsNotInROB(ThreadID tid); /** Remove all instructions younger than the given sequence number. */ void removeInstsUntil(const InstSeqNum &seq_num, ThreadID tid); /** Removes the instruction pointed to by the iterator. */ inline void squashInstIt(const ListIt &instIt, ThreadID tid); /** Cleans up all instructions on the remove list. */ void cleanUpRemovedInsts(); /** Debug function to print all instructions on the list. */ void dumpInsts(); public: #ifndef NDEBUG /** Count of total number of dynamic instructions in flight. */ int instcount; #endif /** List of all the instructions in flight. */ std::list instList; /** List of all the instructions that will be removed at the end of this * cycle. */ std::queue removeList; #ifdef DEBUG /** Debug structure to keep track of the sequence numbers still in * flight. */ std::set snList; #endif /** Records if instructions need to be removed this cycle due to * being retired or squashed. */ bool removeInstsThisCycle; protected: /** The fetch stage. */ typename CPUPolicy::Fetch fetch; /** The decode stage. */ typename CPUPolicy::Decode decode; /** The dispatch stage. */ typename CPUPolicy::Rename rename; /** The issue/execute/writeback stages. */ typename CPUPolicy::IEW iew; /** The commit stage. */ typename CPUPolicy::Commit commit; /** The rename mode of the vector registers */ Enums::VecRegRenameMode vecMode; /** The register file. */ PhysRegFile regFile; /** The free list. */ typename CPUPolicy::FreeList freeList; /** The rename map. */ typename CPUPolicy::RenameMap renameMap[Impl::MaxThreads]; /** The commit rename map. */ typename CPUPolicy::RenameMap commitRenameMap[Impl::MaxThreads]; /** The re-order buffer. */ typename CPUPolicy::ROB rob; /** Active Threads List */ std::list activeThreads; /** Integer Register Scoreboard */ Scoreboard scoreboard; std::vector isa; /** Instruction port. Note that it has to appear after the fetch stage. */ IcachePort icachePort; /** Data port. Note that it has to appear after the iew stages */ DcachePort dcachePort; public: /** Enum to give each stage a specific index, so when calling * activateStage() or deactivateStage(), they can specify which stage * is being activated/deactivated. */ enum StageIdx { FetchIdx, DecodeIdx, RenameIdx, IEWIdx, CommitIdx, NumStages }; /** Typedefs from the Impl to get the structs that each of the * time buffers should use. */ typedef typename CPUPolicy::TimeStruct TimeStruct; typedef typename CPUPolicy::FetchStruct FetchStruct; typedef typename CPUPolicy::DecodeStruct DecodeStruct; typedef typename CPUPolicy::RenameStruct RenameStruct; typedef typename CPUPolicy::IEWStruct IEWStruct; /** The main time buffer to do backwards communication. */ TimeBuffer timeBuffer; /** The fetch stage's instruction queue. */ TimeBuffer fetchQueue; /** The decode stage's instruction queue. */ TimeBuffer decodeQueue; /** The rename stage's instruction queue. */ TimeBuffer renameQueue; /** The IEW stage's instruction queue. */ TimeBuffer iewQueue; private: /** The activity recorder; used to tell if the CPU has any * activity remaining or if it can go to idle and deschedule * itself. */ ActivityRecorder activityRec; public: /** Records that there was time buffer activity this cycle. */ void activityThisCycle() { activityRec.activity(); } /** Changes a stage's status to active within the activity recorder. */ void activateStage(const StageIdx idx) { activityRec.activateStage(idx); } /** Changes a stage's status to inactive within the activity recorder. */ void deactivateStage(const StageIdx idx) { activityRec.deactivateStage(idx); } /** Wakes the CPU, rescheduling the CPU if it's not already active. */ void wakeCPU(); virtual void wakeup(ThreadID tid) override; /** Gets a free thread id. Use if thread ids change across system. */ ThreadID getFreeTid(); public: /** Returns a pointer to a thread context. */ ThreadContext * tcBase(ThreadID tid) { return thread[tid]->getTC(); } /** The global sequence number counter. */ InstSeqNum globalSeqNum;//[Impl::MaxThreads]; /** Pointer to the checker, which can dynamically verify * instruction results at run time. This can be set to NULL if it * is not being used. */ Checker *checker; /** Pointer to the system. */ System *system; /** Pointers to all of the threads in the CPU. */ std::vector thread; /** Threads Scheduled to Enter CPU */ std::list cpuWaitList; /** The cycle that the CPU was last running, used for statistics. */ Cycles lastRunningCycle; /** The cycle that the CPU was last activated by a new thread*/ Tick lastActivatedCycle; /** Mapping for system thread id to cpu id */ std::map threadMap; /** Available thread ids in the cpu*/ std::vector tids; /** CPU pushRequest function, forwards request to LSQ. */ Fault pushRequest(const DynInstPtr& inst, bool isLoad, uint8_t *data, unsigned int size, Addr addr, Request::Flags flags, uint64_t *res) { return iew.ldstQueue.pushRequest(inst, isLoad, data, size, addr, flags, res); } /** CPU read function, forwards read to LSQ. */ Fault read(LSQRequest* req, int load_idx) { return this->iew.ldstQueue.read(req, load_idx); } /** CPU write function, forwards write to LSQ. */ Fault write(LSQRequest* req, uint8_t *data, int store_idx) { return this->iew.ldstQueue.write(req, data, store_idx); } /** Used by the fetch unit to get a hold of the instruction port. */ MasterPort &getInstPort() override { return icachePort; } /** Get the dcache port (used to find block size for translations). */ MasterPort &getDataPort() override { return dcachePort; } /** Stat for total number of times the CPU is descheduled. */ Stats::Scalar timesIdled; /** Stat for total number of cycles the CPU spends descheduled. */ Stats::Scalar idleCycles; /** Stat for total number of cycles the CPU spends descheduled due to a * quiesce operation or waiting for an interrupt. */ Stats::Scalar quiesceCycles; /** Stat for the number of committed instructions per thread. */ Stats::Vector committedInsts; /** Stat for the number of committed ops (including micro ops) per thread. */ Stats::Vector committedOps; /** Stat for the CPI per thread. */ Stats::Formula cpi; /** Stat for the total CPI. */ Stats::Formula totalCpi; /** Stat for the IPC per thread. */ Stats::Formula ipc; /** Stat for the total IPC. */ Stats::Formula totalIpc; //number of integer register file accesses Stats::Scalar intRegfileReads; Stats::Scalar intRegfileWrites; //number of float register file accesses Stats::Scalar fpRegfileReads; Stats::Scalar fpRegfileWrites; //number of vector register file accesses mutable Stats::Scalar vecRegfileReads; Stats::Scalar vecRegfileWrites; //number of CC register file accesses Stats::Scalar ccRegfileReads; Stats::Scalar ccRegfileWrites; //number of misc Stats::Scalar miscRegfileReads; Stats::Scalar miscRegfileWrites; }; #endif // __CPU_O3_CPU_HH__