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#include "sim/power/power_model.hh"

#include "base/statistics.hh"
#include "params/PowerModel.hh"
#include "params/PowerModelState.hh"
#include "sim/clocked_object.hh"
#include "sim/sub_system.hh"

namespace gem5
{

PowerModelState::PowerModelState(const Params &p)
    : SimObject(p), _temp(0), clocked_object(NULL),
      ADD_STAT(dynamicPower, statistics::units::Watt::get(),
               "Dynamic power for this object (Watts)"),
      ADD_STAT(staticPower, statistics::units::Watt::get(),
               "Static power for this object (Watts)")
{
    dynamicPower
      .method(this, &PowerModelState::getDynamicPower);
    staticPower
      .method(this, &PowerModelState::getStaticPower);
}

PowerModel::PowerModel(const Params &p)
    : SimObject(p), states_pm(p.pm), subsystem(p.subsystem),
      clocked_object(NULL), power_model_type(p.pm_type),
      ADD_STAT(dynamicPower, statistics::units::Watt::get(),
                         "Dynamic power for this power state"),
      ADD_STAT(staticPower, statistics::units::Watt::get(),
                         "Static power for this power state")
{
    panic_if(subsystem == NULL,
             "Subsystem is NULL! This is not acceptable for a PowerModel!\n");
    subsystem->registerPowerProducer(this);
    // The temperature passed here will be overwritten, if there is
    // a thermal model present
    for (auto & pms: states_pm){
        pms->setTemperature(p.ambient_temp);
    }

    dynamicPower
      .method(this, &PowerModel::getDynamicPower);
    staticPower
      .method(this, &PowerModel::getStaticPower);

}

void
PowerModel::setClockedObject(ClockedObject * clkobj)
{
    this->clocked_object = clkobj;

    for (auto & pms: states_pm)
        pms->setClockedObject(clkobj);
}

void
PowerModel::thermalUpdateCallback(const Temperature &temp)
{
    for (auto & pms: states_pm)
        pms->setTemperature(temp);
}

void
PowerModel::regProbePoints()
{
    thermalListener.reset(new ThermalProbeListener (
        *this, this->subsystem->getProbeManager(), "thermalUpdate"
    ));
}

double
PowerModel::getDynamicPower() const
{
    assert(clocked_object);

    if (power_model_type == enums::PMType::Static) {
        // This power model only collects static data
        return 0;
    }
    std::vector<double> w = clocked_object->powerState->getWeights();

    // Same number of states (excluding UNDEFINED)
    assert(w.size() - 1 == states_pm.size());

    // Make sure we have no UNDEFINED state
    warn_if(w[enums::PwrState::UNDEFINED] > 0,
        "SimObject in UNDEFINED power state! Power figures might be wrong!\n");

    double power = 0;
    for (unsigned i = 0; i < states_pm.size(); i++)
        if (w[i + 1] > 0.0f)
            power += states_pm[i]->getDynamicPower() * w[i + 1];

    return power;
}

double
PowerModel::getStaticPower() const
{
    assert(clocked_object);

    std::vector<double> w = clocked_object->powerState->getWeights();

    if (power_model_type == enums::PMType::Dynamic) {
        // This power model only collects dynamic data
        return 0;
    }

    // Same number of states (excluding UNDEFINED)
    assert(w.size() - 1 == states_pm.size());

    // Make sure we have no UNDEFINED state
    if (w[0] > 0)
        warn("SimObject in UNDEFINED power state! "
             "Power figures might be wrong!\n");

    // We have N+1 states, being state #0 the default 'UNDEFINED' state
    double power = 0;
    for (unsigned i = 0; i < states_pm.size(); i++)
        // Don't evaluate power if the object hasn't been in that state
        // This fixes issues with NaNs and similar.
        if (w[i + 1] > 0.0f)
            power += states_pm[i]->getStaticPower() * w[i + 1];

    return power;
}

} // namespace gem5