text: /*
   * Copyright (c) 2012-2013, 2015-2016 ARM Limited
   * Copyright (c) 2013 Cornell University
   * 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.
   *
   * 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: Andreas Hansson
   *          Christopher Torng
   *          Akash Bagdia
   *          David Guillen Fandos
   */
  
  /**
   * @file
   * ClockedObject declaration and implementation.
   */
  
  #ifndef __SIM_CLOCKED_OBJECT_HH__
  #define __SIM_CLOCKED_OBJECT_HH__
  
  #include "base/callback.hh"
  #include "base/intmath.hh"
  #include "enums/PwrState.hh"
  #include "params/ClockedObject.hh"
  #include "sim/core.hh"
  #include "sim/clock_domain.hh"
  #include "sim/sim_object.hh"
  
  /**
   * Helper class for objects that need to be clocked. Clocked objects
   * typically inherit from this class. Objects that need SimObject
   * functionality as well should inherit from ClockedObject.
   */
  class Clocked
  {
  
    private:
      // the tick value of the next clock edge (>= curTick()) at the
      // time of the last call to update()
      mutable Tick tick;
  
      // The cycle counter value corresponding to the current value of
      // 'tick'
      mutable Cycles cycle;
  
      /**
       *  Align cycle and tick to the next clock edge if not already done. When
       *  complete, tick must be at least curTick().
       */
      void
      update() const
      {
          // both tick and cycle are up-to-date and we are done, note
          // that the >= is important as it captures cases where tick
          // has already passed curTick()
          if (tick >= curTick())
              return;
  
          // optimise for the common case and see if the tick should be
          // advanced by a single clock period
          tick += clockPeriod();
          ++cycle;
  
          // see if we are done at this point
          if (tick >= curTick())
              return;
  
          // if not, we have to recalculate the cycle and tick, we
          // perform the calculations in terms of relative cycles to
          // allow changes to the clock period in the future
          Cycles elapsedCycles(divCeil(curTick() - tick, clockPeriod()));
          cycle += elapsedCycles;
          tick += elapsedCycles * clockPeriod();
      }
  
      /**
       * The clock domain this clocked object belongs to
       */
      ClockDomain &clockDomain;
  
    protected:
  
      /**
       * Create a clocked object and set the clock domain based on the
       * parameters.
       */
      Clocked(ClockDomain &clk_domain)
          : tick(0), cycle(0), clockDomain(clk_domain)
      {
          // Register with the clock domain, so that if the clock domain
          // frequency changes, we can update this object's tick.
          clockDomain.registerWithClockDomain(this);
      }
  
      Clocked(Clocked &) = delete;
      Clocked &operator=(Clocked &) = delete;
  
      /**
       * Virtual destructor due to inheritance.
       */
      virtual ~Clocked() { }
  
      /**
       * Reset the object's clock using the current global tick value. Likely
       * to be used only when the global clock is reset. Currently, this done
       * only when Ruby is done warming up the memory system.
       */
      void
      resetClock() const
      {
          Cycles elapsedCycles(divCeil(curTick(), clockPeriod()));
          cycle = elapsedCycles;
          tick = elapsedCycles * clockPeriod();
      }
  
      /**
       * A hook subclasses can implement so they can do any extra work that's
       * needed when the clock rate is changed.
       */
      virtual void clockPeriodUpdated() {}
  
    public:
  
      /**
       * Update the tick to the current tick.
       */
      void
      updateClockPeriod()
      {
          update();
          clockPeriodUpdated();
      }
  
      /**
       * Determine the tick when a cycle begins, by default the current one, but
       * the argument also enables the caller to determine a future cycle. When
       * curTick() is on a clock edge, the number of cycles in the parameter is
       * added to curTick() to be returned. When curTick() is not aligned to a
       * clock edge, the number of cycles in the parameter is added to the next
       * clock edge.
       *
       * @param cycles The number of cycles into the future
       *
       * @return The start tick when the requested clock edge occurs. Precisely,
       * this tick can be
       *     curTick() + [0, clockPeriod()) + clockPeriod() * cycles
       */
      Tick
      clockEdge(Cycles cycles=Cycles(0)) const
      {
          // align tick to the next clock edge
          update();
  
          // figure out when this future cycle is
          return tick + clockPeriod() * cycles;
      }
  
      /**
       * Determine the current cycle, corresponding to a tick aligned to
       * a clock edge.
       *
       * @return When curTick() is on a clock edge, return the Cycle corresponding
       * to that clock edge. When curTick() is not on a clock edge, return the
       * Cycle corresponding to the next clock edge.
       */
      Cycles
      curCycle() const
      {
          // align cycle to the next clock edge.
          update();
  
          return cycle;
      }
  
      /**
       * Based on the clock of the object, determine the start tick of the first
       * cycle that is at least one cycle in the future. When curTick() is at the
       * current cycle edge, this returns the next clock edge. When calling this
       * during the middle of a cycle, this returns 2 clock edges in the future.
       *
       * @return The start tick of the first cycle that is at least one cycle in
       * the future. Precisely, the returned tick can be in the range
       *     curTick() + [clockPeriod(), 2 * clockPeriod())
       */
      Tick nextCycle() const { return clockEdge(Cycles(1)); }
  
      uint64_t frequency() const { return SimClock::Frequency / clockPeriod(); }
  
      Tick clockPeriod() const { return clockDomain.clockPeriod(); }
  
      double voltage() const { return clockDomain.voltage(); }
  
      Cycles
      ticksToCycles(Tick t) const
      {
          return Cycles(divCeil(t, clockPeriod()));
      }
  
      Tick cyclesToTicks(Cycles c) const { return clockPeriod() * c; }
  };
  
  /**
   * The ClockedObject class extends the SimObject with a clock and
   * accessor functions to relate ticks to the cycles of the object.
   */
  class ClockedObject : public SimObject, public Clocked
  {
    private:
  
    public:
      ClockedObject(const ClockedObjectParams *p);
      static int clkpower;
      static bool l2_flushed_core0;
      static bool dcache_flushed_core0;
      static bool icache_flushed_core0;
      static bool l2_flushed_core1;
      static bool dcache_flushed_core1;
      static bool icache_flushed_core1;
      static bool l2_flushed_core2;
      static bool dcache_flushed_core2;
      static bool icache_flushed_core2;
      static bool l2_flushed_core3;
      static bool dcache_flushed_core3;
      static bool icache_flushed_core3;
  
      /** Parameters of ClockedObject */
      typedef ClockedObjectParams Params;
      const Params *
      params() const
      {
          return reinterpret_cast<const Params*>(_params);
      }
  
      void serialize(CheckpointOut &cp) const override;
      void unserialize(CheckpointIn &cp) override;
  
      Enums::PwrState pwrState() const { return _currPwrState; }
      std::string
      pwrStateName() const
      {
          return Enums::PwrStateStrings[_currPwrState];
      }
  
      /** Returns the percentage residency for each power state */
      std::vector<double> pwrStateWeights() const;
      int GetVal()
      {
          return clkpower;
      }
  /*
       void SetVal( int newVal )
      {
          clkpower = newVal;
      }
      */
      /**
       * Record stats values like state residency by computing the time
       * difference from previous update. Also, updates the previous evaluation
       * tick once all stats are recorded.
       * Usually called on power state change and stats dump callback.
       */
      void computeStats();
  
      void pwrState(Enums::PwrState);
      void regStats() override;
  
    protected:
  
      /** To keep track of the current power state */
      Enums::PwrState _currPwrState;
  
      Tick prvEvalTick;
  
      Stats::Scalar numPwrStateTransitions;
      Stats::Distribution pwrStateClkGateDist;
      Stats::Vector pwrStateResidencyTicks;
  
  };
  
  
  class ClockedObjectDumpCallback : public Callback
  {
      ClockedObject *co;
    public:
      ClockedObjectDumpCallback(ClockedObject *co_t) : co(co_t) {}
      virtual void process() { co->computeStats(); };
  };
  
  #endif //__SIM_CLOCKED_OBJECT_HH__
  