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/*
* Copyright (c) 2012-2014, 2019 ARM Limited
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#include "sim/voltage_domain.hh"
#include <algorithm>
#include "base/logging.hh"
#include "base/trace.hh"
#include "debug/VoltageDomain.hh"
#include "params/VoltageDomain.hh"
#include "sim/serialize.hh"
namespace gem5
{
VoltageDomain::VoltageDomain(const Params &p)
: SimObject(p), voltageOpPoints(p.voltage), _perfLevel(0), stats(*this)
{
fatal_if(voltageOpPoints.empty(), "DVFS: Empty set of voltages for "\
"voltage domain %s\n", name());
// Voltages must be sorted in descending order.
fatal_if(!std::is_sorted(voltageOpPoints.begin(), voltageOpPoints.end(),
std::greater<Voltages::value_type>()), "DVFS: Voltage operation "\
"points not in descending order for voltage domain %s\n",
name());
}
void
VoltageDomain::perfLevel(PerfLevel perf_level)
{
gem5_assert(perf_level < voltageOpPoints.size(),
"DVFS: Requested voltage ID %d is outside the known "\
"range for domain %s.\n", perf_level, name());
if (perf_level == _perfLevel) {
// Silently ignore identical overwrites
return;
}
_perfLevel = perf_level;
DPRINTF(VoltageDomain, "Setting voltage to %.3fV idx: %d for domain %s\n",
voltage(), perf_level, name());
}
bool
VoltageDomain::sanitiseVoltages()
{
if (numVoltages() == 1)
return false;
// Find the highest requested performance level and update the voltage
// domain with it
PerfLevel perf_max = (PerfLevel)-1;
for (auto dit = srcClockChildren.begin(); dit != srcClockChildren.end();
++dit) {
SrcClockDomain* d = *dit;
gem5_assert(d->voltageDomain() == this, "DVFS: Clock domain %s "\
"(id: %d) should not be registered with voltage domain "\
"%s\n", d->name(), d->domainID(), name());
PerfLevel perf = d->perfLevel();
DPRINTF(VoltageDomain, "DVFS: Clock domain %s (id: %d) requests perf "\
"level %d\n", d->name(), d->domainID(), perf);
// NOTE: Descending sort of performance levels: 0 - fast, 5 - slow
if (perf < perf_max) {
DPRINTF(VoltageDomain, "DVFS: Updating max perf level %d -> %d\n",
perf_max, perf);
perf_max = perf;
}
}
DPRINTF(VoltageDomain, "DVFS: Setting perf level of voltage domain %s "\
"from %d to %d.\n", name(), perfLevel(), perf_max);
// Set the performance level
if (perf_max != perfLevel()) {
perfLevel(perf_max);
return true;
} else {
return false;
}
}
void
VoltageDomain::startup() {
bool changed = sanitiseVoltages();
if (changed) {
warn("DVFS: Perf level for voltage domain %s adapted to "\
"requested perf levels from source clock domains.\n", name());
}
}
void
VoltageDomain::serialize(CheckpointOut &cp) const
{
SERIALIZE_SCALAR(_perfLevel);
}
void
VoltageDomain::unserialize(CheckpointIn &cp)
{
UNSERIALIZE_SCALAR(_perfLevel);
perfLevel(_perfLevel);
}
VoltageDomain::VoltageDomainStats::VoltageDomainStats(VoltageDomain &vd)
: statistics::Group(&vd),
ADD_STAT(voltage, statistics::units::Volt::get(), "Voltage in Volts")
{
voltage.method(&vd, &VoltageDomain::voltage);
}
} // namespace gem5