power: Add power states to ClockedObject

Add 4 power states to the ClockedObject, provides necessary access functions
to check and update the power state. Default power state is UNDEFINED, it is
responsibility of the respective simulation model to provide the startup state
and any other logic for state change.

Add number of transition stat.
Add distribution of time spent in clock gated state.
Add power state residency stat.

Add dump call back function to allow stats update of distribution and residency
stats.

1 files changed, 57 insertions, 2 deletions

diff --git a/src/sim/clocked_object.hh b/src/sim/clocked_object.hh
index b9a2481ec..1ba5ca617 100644
--- a/src/sim/clocked_object.hh
+++ b/src/sim/clocked_object.hh
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012-2013 ARM Limited
+ * Copyright (c) 2012-2013, 2015 ARM Limited
  * Copyright (c) 2013 Cornell University
  * All rights reserved
  *
@@ -37,6 +37,8 @@
  *
  * Authors: Andreas Hansson
  *          Christopher Torng
+ *          Akash Bagdia
+ *          David Guillen Fandos
  */
 
 /**
@@ -47,8 +49,10 @@
 #ifndef __SIM_CLOCKED_OBJECT_HH__
 #define __SIM_CLOCKED_OBJECT_HH__
 
+#include "base/callback.hh"
 #include "base/intmath.hh"
 #include "base/misc.hh"
+#include "enums/PwrState.hh"
 #include "params/ClockedObject.hh"
 #include "sim/core.hh"
 #include "sim/clock_domain.hh"
@@ -233,7 +237,58 @@ class ClockedObject
 {
   public:
     ClockedObject(const ClockedObjectParams *p)
-        : SimObject(p), Clocked(*p->clk_domain) { }
+        : SimObject(p), Clocked(*p->clk_domain),
+        _currPwrState(p->default_p_state),
+        prvEvalTick(0)
+    { }
+
+    /** 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;
+
+    inline Enums::PwrState pwrState() const
+    { return _currPwrState; }
+
+    inline std::string pwrStateName() const
+    { return Enums::PwrStateStrings[_currPwrState]; }
+
+    /** Returns the percentage residency for each power state */
+    std::vector<double> pwrStateWeights() const;
+
+    /**
+     * 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();
+
+  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__