/*
 * Copyright (c) 2009 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: Gabe Black
 */

#ifndef __ARCH_MIPS_ISA_HH__
#define __ARCH_MIPS_ISA_HH__

#include <queue>
#include <string>
#include <vector>

#include "arch/mips/registers.hh"
#include "arch/mips/types.hh"
#include "sim/eventq.hh"
#include "sim/fault_fwd.hh"

class BaseCPU;
class Checkpoint;
class EventManager;
class ThreadContext;

namespace MipsISA
{
    class ISA
    {
      public:
        // The MIPS name for this file is CP0 or Coprocessor 0
        typedef ISA CP0;

      protected:
        // Number of threads and vpes an individual ISA state can handle
        uint8_t numThreads;
        uint8_t numVpes;

        enum BankType {
            perProcessor,
            perThreadContext,
            perVirtProcessor
        };

        std::vector<std::vector<MiscReg> > miscRegFile;
        std::vector<std::vector<MiscReg> > miscRegFile_WriteMask;
        std::vector<BankType> bankType;

      public:
        ISA(uint8_t num_threads = 1, uint8_t num_vpes = 1);

        void clear();

        void configCP();

        unsigned getVPENum(ThreadID tid);

        //////////////////////////////////////////////////////////
        //
        // READ/WRITE CP0 STATE
        //
        //
        //////////////////////////////////////////////////////////
        //@TODO: MIPS MT's register view automatically connects
        //       Status to TCStatus depending on current thread
        void updateCP0ReadView(int misc_reg, ThreadID tid) { }
        MiscReg readMiscRegNoEffect(int misc_reg, ThreadID tid = 0);

        //template <class TC>
        MiscReg readMiscReg(int misc_reg,
                            ThreadContext *tc, ThreadID tid = 0);

        MiscReg filterCP0Write(int misc_reg, int reg_sel, const MiscReg &val);
        void setRegMask(int misc_reg, const MiscReg &val, ThreadID tid = 0);
        void setMiscRegNoEffect(int misc_reg, const MiscReg &val,
                                ThreadID tid = 0);

        //template <class TC>
        void setMiscReg(int misc_reg, const MiscReg &val,
                        ThreadContext *tc, ThreadID tid = 0);

        //////////////////////////////////////////////////////////
        //
        // DECLARE INTERFACE THAT WILL ALLOW A MiscRegFile (Cop0)
        // TO SCHEDULE EVENTS
        //
        //////////////////////////////////////////////////////////

        // Flag that is set when CP0 state has been written to.
        bool cp0Updated;

        // Enumerated List of CP0 Event Types
        enum CP0EventType {
            UpdateCP0
        };

        // Declare A CP0Event Class for scheduling
        class CP0Event : public Event
        {
          protected:
            ISA::CP0 *cp0;
            BaseCPU *cpu;
            CP0EventType cp0EventType;
            Fault fault;

          public:
            /** Constructs a CP0 event. */
            CP0Event(CP0 *_cp0, BaseCPU *_cpu, CP0EventType e_type);

            /** Process this event. */
            virtual void process();

            /** Returns the description of this event. */
            const char *description() const;

            /** Schedule This Event */
            void scheduleEvent(int delay);

            /** Unschedule This Event */
            void unscheduleEvent();
        };

        // Schedule a CP0 Update Event
        void scheduleCP0Update(BaseCPU *cpu, int delay = 0);

        // If any changes have been made, then check the state for changes
        // and if necessary alert the CPU
        void updateCPU(BaseCPU *cpu);

        // Keep a List of CPU Events that need to be deallocated
        std::queue<CP0Event*> cp0EventRemoveList;

        static std::string miscRegNames[NumMiscRegs];

      public:

        int
        flattenIntIndex(int reg)
        {
            return reg;
        }

        int
        flattenFloatIndex(int reg)
        {
            return reg;
        }

        void serialize(EventManager *em, std::ostream &os)
        {}
        void unserialize(EventManager *em, Checkpoint *cp,
                const std::string &section)
        {}
    };
}

#endif
