/*
 * Copyright (c) 2004-2006 The Regents of The University of Michigan
 * 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
 */

#ifndef __CPU_O3_ALPHA_FULL_CPU_HH__
#define __CPU_O3_ALPHA_FULL_CPU_HH__

#include "arch/isa_traits.hh"
#include "cpu/exec_context.hh"
#include "cpu/o3/cpu.hh"
#include "sim/byteswap.hh"

class EndQuiesceEvent;
namespace Kernel {
    class Statistics;
};

class TranslatingPort;

template <class Impl>
class AlphaFullCPU : public FullO3CPU<Impl>
{
  protected:
    typedef TheISA::IntReg IntReg;
    typedef TheISA::FloatReg FloatReg;
    typedef TheISA::FloatRegBits FloatRegBits;
    typedef TheISA::MiscReg MiscReg;
    typedef TheISA::RegFile RegFile;
    typedef TheISA::MiscRegFile MiscRegFile;

  public:
    typedef O3ThreadState<Impl> ImplState;
    typedef O3ThreadState<Impl> Thread;
    typedef typename Impl::Params Params;

    /** Constructs an AlphaFullCPU with the given parameters. */
    AlphaFullCPU(Params *params);

    class AlphaXC : public ExecContext
    {
      public:
        AlphaFullCPU<Impl> *cpu;

        O3ThreadState<Impl> *thread;

        virtual BaseCPU *getCpuPtr() { return cpu; }

        virtual void setCpuId(int id) { cpu->cpu_id = id; }

        virtual int readCpuId() { return cpu->cpu_id; }

        virtual TranslatingPort *getMemPort() { return /*thread->port*/ NULL; }

#if FULL_SYSTEM
        virtual System *getSystemPtr() { return cpu->system; }

        virtual PhysicalMemory *getPhysMemPtr() { return cpu->physmem; }

        virtual AlphaITB *getITBPtr() { return cpu->itb; }

        virtual AlphaDTB * getDTBPtr() { return cpu->dtb; }

        virtual Kernel::Statistics *getKernelStats()
        { return thread->kernelStats; }
#else
        virtual Process *getProcessPtr() { return thread->process; }
#endif

        virtual Status status() const { return thread->status(); }

        virtual void setStatus(Status new_status)
        { thread->setStatus(new_status); }

        /// Set the status to Active.  Optional delay indicates number of
        /// cycles to wait before beginning execution.
        virtual void activate(int delay = 1);

        /// Set the status to Suspended.
        virtual void suspend();

        /// Set the status to Unallocated.
        virtual void deallocate();

        /// Set the status to Halted.
        virtual void halt();

#if FULL_SYSTEM
        virtual void dumpFuncProfile();
#endif

        virtual void takeOverFrom(ExecContext *old_context);

        virtual void regStats(const std::string &name);

        virtual void serialize(std::ostream &os);
        virtual void unserialize(Checkpoint *cp, const std::string &section);

#if FULL_SYSTEM
        virtual EndQuiesceEvent *getQuiesceEvent();

        virtual Tick readLastActivate();
        virtual Tick readLastSuspend();

        virtual void profileClear();
        virtual void profileSample();
#endif

        virtual int getThreadNum() { return thread->tid; }

        virtual TheISA::MachInst getInst();

        virtual void copyArchRegs(ExecContext *xc);

        virtual void clearArchRegs();

        virtual uint64_t readIntReg(int reg_idx);

        virtual FloatReg readFloatReg(int reg_idx, int width);

        virtual FloatReg readFloatReg(int reg_idx);

        virtual FloatRegBits readFloatRegBits(int reg_idx, int width);

        virtual FloatRegBits readFloatRegBits(int reg_idx);

        virtual void setIntReg(int reg_idx, uint64_t val);

        virtual void setFloatReg(int reg_idx, FloatReg val, int width);

        virtual void setFloatReg(int reg_idx, FloatReg val);

        virtual void setFloatRegBits(int reg_idx, FloatRegBits val, int width);

        virtual void setFloatRegBits(int reg_idx, FloatRegBits val);

        virtual uint64_t readPC()
        { return cpu->readPC(thread->tid); }

        virtual void setPC(uint64_t val);

        virtual uint64_t readNextPC()
        { return cpu->readNextPC(thread->tid); }

        virtual void setNextPC(uint64_t val);

        virtual uint64_t readNextNPC()
        {
            panic("Alpha has no NextNPC!");
            return 0;
        }

        virtual void setNextNPC(uint64_t val)
        { panic("Alpha has no NextNPC!"); }

        virtual MiscReg readMiscReg(int misc_reg)
        { return cpu->readMiscReg(misc_reg, thread->tid); }

        virtual MiscReg readMiscRegWithEffect(int misc_reg, Fault &fault)
        { return cpu->readMiscRegWithEffect(misc_reg, fault, thread->tid); }

        virtual Fault setMiscReg(int misc_reg, const MiscReg &val);

        virtual Fault setMiscRegWithEffect(int misc_reg, const MiscReg &val);

        // @todo: Figure out where these store cond failures should go.
        virtual unsigned readStCondFailures()
        { return thread->storeCondFailures; }

        virtual void setStCondFailures(unsigned sc_failures)
        { thread->storeCondFailures = sc_failures; }

#if FULL_SYSTEM
        virtual bool inPalMode()
        { return TheISA::PcPAL(cpu->readPC(thread->tid)); }
#endif

        // Only really makes sense for old CPU model.  Lots of code
        // outside the CPU still checks this function, so it will
        // always return false to keep everything working.
        virtual bool misspeculating() { return false; }

#if !FULL_SYSTEM
        virtual IntReg getSyscallArg(int i);

        virtual void setSyscallArg(int i, IntReg val);

        virtual void setSyscallReturn(SyscallReturn return_value);

        virtual void syscall(int64_t callnum)
        { return cpu->syscall(callnum, thread->tid); }

        virtual Counter readFuncExeInst() { return thread->funcExeInst; }
#endif
        virtual void changeRegFileContext(TheISA::RegFile::ContextParam param,
                                          TheISA::RegFile::ContextVal val)
        { panic("Not supported on Alpha!"); }
    };

#if FULL_SYSTEM
    /** ITB pointer. */
    AlphaITB *itb;
    /** DTB pointer. */
    AlphaDTB *dtb;
#endif

    /** Registers statistics. */
    void regStats();

#if FULL_SYSTEM
    /** Translates instruction requestion. */
    Fault translateInstReq(RequestPtr &req)
    {
        return itb->translate(req);
    }

    /** Translates data read request. */
    Fault translateDataReadReq(RequestPtr &req)
    {
        return dtb->translate(req, false);
    }

    /** Translates data write request. */
    Fault translateDataWriteReq(RequestPtr &req)
    {
        return dtb->translate(req, true);
    }

#else
    /** Translates instruction requestion in syscall emulation mode. */
    Fault translateInstReq(RequestPtr &req)
    {
        int tid = req->getThreadNum();
        return this->thread[tid]->process->pTable->translate(req);
    }

    /** Translates data read request in syscall emulation mode. */
    Fault translateDataReadReq(RequestPtr &req)
    {
        int tid = req->getThreadNum();
        return this->thread[tid]->process->pTable->translate(req);
    }

    /** Translates data write request in syscall emulation mode. */
    Fault translateDataWriteReq(RequestPtr &req)
    {
        int tid = req->getThreadNum();
        return this->thread[tid]->process->pTable->translate(req);
    }

#endif
    MiscReg readMiscReg(int misc_reg, unsigned tid);

    MiscReg readMiscRegWithEffect(int misc_reg, Fault &fault, unsigned tid);

    Fault setMiscReg(int misc_reg, const MiscReg &val, unsigned tid);

    Fault setMiscRegWithEffect(int misc_reg, const MiscReg &val, unsigned tid);

    void squashFromXC(unsigned tid);

#if FULL_SYSTEM
    void post_interrupt(int int_num, int index);

    int readIntrFlag();
    /** Sets the interrupt flags. */
    void setIntrFlag(int val);
    /** HW return from error interrupt. */
    Fault hwrei(unsigned tid);
    /** Returns if a specific PC is a PAL mode PC. */
    bool inPalMode(uint64_t PC)
    { return AlphaISA::PcPAL(PC); }

    /** Traps to handle given fault. */
    void trap(Fault fault, unsigned tid);
    bool simPalCheck(int palFunc, unsigned tid);

    /** Processes any interrupts. */
    void processInterrupts();

    /** Halts the CPU. */
    void halt() { panic("Halt not implemented!\n"); }
#endif


#if !FULL_SYSTEM
    /** Executes a syscall.
     * @todo: Determine if this needs to be virtual.
     */
    void syscall(int64_t callnum, int thread_num);
    /** Gets a syscall argument. */
    IntReg getSyscallArg(int i, int tid);

    /** Used to shift args for indirect syscall. */
    void setSyscallArg(int i, IntReg val, int tid);

    /** Sets the return value of a syscall. */
    void setSyscallReturn(SyscallReturn return_value, int tid);
#endif

    /** Read from memory function. */
    template <class T>
    Fault read(RequestPtr &req, T &data)
    {
#if 0
#if FULL_SYSTEM && THE_ISA == ALPHA_ISA
        if (req->flags & LOCKED) {
            req->xc->setMiscReg(TheISA::Lock_Addr_DepTag, req->paddr);
            req->xc->setMiscReg(TheISA::Lock_Flag_DepTag, true);
        }
#endif
#endif
        Fault error;

#if FULL_SYSTEM
        // @todo: Fix this LL/SC hack.
        if (req->flags & LOCKED) {
            lockAddr = req->paddr;
            lockFlag = true;
        }
#endif

        error = this->mem->read(req, data);
        data = gtoh(data);
        return error;
    }

    /** CPU read function, forwards read to LSQ. */
    template <class T>
    Fault read(RequestPtr &req, T &data, int load_idx)
    {
        return this->iew.ldstQueue.read(req, data, load_idx);
    }

    /** Write to memory function. */
    template <class T>
    Fault write(RequestPtr &req, T &data)
    {
#if 0
#if FULL_SYSTEM && THE_ISA == ALPHA_ISA
        ExecContext *xc;

        // If this is a store conditional, act appropriately
        if (req->flags & LOCKED) {
            xc = req->xc;

            if (req->flags & UNCACHEABLE) {
                // Don't update result register (see stq_c in isa_desc)
                req->result = 2;
                xc->setStCondFailures(0);//Needed? [RGD]
            } else {
                bool lock_flag = xc->readMiscReg(TheISA::Lock_Flag_DepTag);
                Addr lock_addr = xc->readMiscReg(TheISA::Lock_Addr_DepTag);
                req->result = lock_flag;
                if (!lock_flag ||
                    ((lock_addr & ~0xf) != (req->paddr & ~0xf))) {
                    xc->setMiscReg(TheISA::Lock_Flag_DepTag, false);
                    xc->setStCondFailures(xc->readStCondFailures() + 1);
                    if (((xc->readStCondFailures()) % 100000) == 0) {
                        std::cerr << "Warning: "
                                  << xc->readStCondFailures()
                                  << " consecutive store conditional failures "
                                  << "on cpu " << req->xc->readCpuId()
                                  << std::endl;
                    }
                    return NoFault;
                }
                else xc->setStCondFailures(0);
            }
        }

        // Need to clear any locked flags on other proccessors for
        // this address.  Only do this for succsful Store Conditionals
        // and all other stores (WH64?).  Unsuccessful Store
        // Conditionals would have returned above, and wouldn't fall
        // through.
        for (int i = 0; i < this->system->execContexts.size(); i++){
            xc = this->system->execContexts[i];
            if ((xc->readMiscReg(TheISA::Lock_Addr_DepTag) & ~0xf) ==
                (req->paddr & ~0xf)) {
                xc->setMiscReg(TheISA::Lock_Flag_DepTag, false);
            }
        }

#endif
#endif

#if FULL_SYSTEM
        // @todo: Fix this LL/SC hack.
        if (req->flags & LOCKED) {
            if (req->flags & UNCACHEABLE) {
                req->result = 2;
            } else {
                if (this->lockFlag) {
                    req->result = 1;
                } else {
                    req->result = 0;
                    return NoFault;
                }
            }
        }
#endif

        return this->mem->write(req, (T)htog(data));
    }

    /** CPU write function, forwards write to LSQ. */
    template <class T>
    Fault write(RequestPtr &req, T &data, int store_idx)
    {
        return this->iew.ldstQueue.write(req, data, store_idx);
    }

    Addr lockAddr;

    bool lockFlag;
};

#endif // __CPU_O3_ALPHA_FULL_CPU_HH__