gem5  v21.1.0.2
voltage_domain.cc
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37 
38 #include "sim/voltage_domain.hh"
39 
40 #include <algorithm>
41 
42 #include "base/logging.hh"
43 #include "base/trace.hh"
44 #include "debug/VoltageDomain.hh"
45 #include "params/VoltageDomain.hh"
46 #include "sim/serialize.hh"
47 
48 namespace gem5
49 {
50 
52  : SimObject(p), voltageOpPoints(p.voltage), _perfLevel(0), stats(*this)
53 {
54  fatal_if(voltageOpPoints.empty(), "DVFS: Empty set of voltages for "\
55  "voltage domain %s\n", name());
56 
57  // Voltages must be sorted in descending order.
58  fatal_if(!std::is_sorted(voltageOpPoints.begin(), voltageOpPoints.end(),
59  std::greater<Voltages::value_type>()), "DVFS: Voltage operation "\
60  "points not in descending order for voltage domain %s\n",
61  name());
62 }
63 
64 void
66 {
67  chatty_assert(perf_level < voltageOpPoints.size(),
68  "DVFS: Requested voltage ID %d is outside the known "\
69  "range for domain %s.\n", perf_level, name());
70 
71  if (perf_level == _perfLevel) {
72  // Silently ignore identical overwrites
73  return;
74  }
75 
76  _perfLevel = perf_level;
77 
78  DPRINTF(VoltageDomain, "Setting voltage to %.3fV idx: %d for domain %s\n",
79  voltage(), perf_level, name());
80 }
81 
82 bool
84 {
85  if (numVoltages() == 1)
86  return false;
87 
88  // Find the highest requested performance level and update the voltage
89  // domain with it
90  PerfLevel perf_max = (PerfLevel)-1;
91  for (auto dit = srcClockChildren.begin(); dit != srcClockChildren.end(); ++dit) {
92  SrcClockDomain* d = *dit;
93  chatty_assert(d->voltageDomain() == this, "DVFS: Clock domain %s "\
94  "(id: %d) should not be registered with voltage domain "\
95  "%s\n", d->name(), d->domainID(), name());
96 
97  PerfLevel perf = d->perfLevel();
98 
99  DPRINTF(VoltageDomain, "DVFS: Clock domain %s (id: %d) requests perf "\
100  "level %d\n", d->name(), d->domainID(), perf);
101 
102  // NOTE: Descending sort of performance levels: 0 - fast, 5 - slow
103  if (perf < perf_max) {
104  DPRINTF(VoltageDomain, "DVFS: Updating max perf level %d -> %d\n",
105  perf_max, perf);
106  perf_max = perf;
107  }
108  }
109  DPRINTF(VoltageDomain, "DVFS: Setting perf level of voltage domain %s "\
110  "from %d to %d.\n", name(), perfLevel(), perf_max);
111 
112  // Set the performance level
113  if (perf_max != perfLevel()) {
114  perfLevel(perf_max);
115  return true;
116  } else {
117  return false;
118  }
119 }
120 
121 void
123  bool changed = sanitiseVoltages();
124  if (changed) {
125  warn("DVFS: Perf level for voltage domain %s adapted to "\
126  "requested perf levels from source clock domains.\n", name());
127  }
128 }
129 
130 void
132 {
134 }
135 
136 void
138 {
141 }
142 
144  : statistics::Group(&vd),
145  ADD_STAT(voltage, statistics::units::Volt::get(), "Voltage in Volts")
146 {
148 }
149 
150 } // namespace gem5
gem5::ArmISA::dit
Bitfield< 51, 48 > dit
Definition: misc_types.hh:168
gem5::VoltageDomain::PerfLevel
SrcClockDomain::PerfLevel PerfLevel
Definition: voltage_domain.hh:63
warn
#define warn(...)
Definition: logging.hh:245
voltage_domain.hh
serialize.hh
UNSERIALIZE_SCALAR
#define UNSERIALIZE_SCALAR(scalar)
Definition: serialize.hh:575
gem5::VoltageDomain::VoltageDomain
VoltageDomain(const Params &p)
Definition: voltage_domain.cc:51
gem5::CheckpointIn
Definition: serialize.hh:68
gem5::statistics::ValueBase::method
Derived & method(T *obj, V(T::*method)() const)
Extended functor that calls the specified method of the provided object.
Definition: statistics.hh:763
gem5::VoltageDomain::VoltageDomainStats::VoltageDomainStats
VoltageDomainStats(VoltageDomain &vd)
Definition: voltage_domain.cc:143
gem5::VoltageDomain::startup
void startup() override
Startup has all SrcClockDomains registered with this voltage domain, so try to make sure that all per...
Definition: voltage_domain.cc:122
gem5::VoltageDomain::srcClockChildren
SrcClockChildren srcClockChildren
Definition: voltage_domain.hh:159
gem5::VoltageDomain::serialize
void serialize(CheckpointOut &cp) const override
Serialize an object.
Definition: voltage_domain.cc:131
gem5::SimObject::Params
SimObjectParams Params
Definition: sim_object.hh:170
gem5::VoltageDomain::voltageOpPoints
const Voltages voltageOpPoints
List of possible minimum voltage at each of the frequency operational points, should be in descending...
Definition: voltage_domain.hh:141
gem5::Named::name
virtual std::string name() const
Definition: named.hh:47
DPRINTF
#define DPRINTF(x,...)
Definition: trace.hh:186
ADD_STAT
#define ADD_STAT(n,...)
Convenience macro to add a stat to a statistics group.
Definition: group.hh:75
gem5::ArmISA::d
Bitfield< 9 > d
Definition: misc_types.hh:63
gem5::MipsISA::p
Bitfield< 0 > p
Definition: pra_constants.hh:326
gem5::VoltageDomain::sanitiseVoltages
bool sanitiseVoltages()
Recomputes the highest (fastest, i.e., numerically lowest) requested performance level of all associa...
Definition: voltage_domain.cc:83
chatty_assert
#define chatty_assert(cond,...)
The chatty assert macro will function like a normal assert, but will allow the specification of addit...
Definition: logging.hh:301
gem5::SrcClockDomain
The source clock domains provides the notion of a clock domain that is connected to a tunable clock s...
Definition: clock_domain.hh:166
gem5::VoltageDomain::_perfLevel
PerfLevel _perfLevel
Definition: voltage_domain.hh:142
gem5::SimObject
Abstract superclass for simulation objects.
Definition: sim_object.hh:146
SERIALIZE_SCALAR
#define SERIALIZE_SCALAR(scalar)
Definition: serialize.hh:568
gem5::VoltageDomain::unserialize
void unserialize(CheckpointIn &cp) override
Unserialize an object.
Definition: voltage_domain.cc:137
gem5::VoltageDomain::perfLevel
PerfLevel perfLevel() const
Get the voltage point of the domain.
Definition: voltage_domain.hh:99
gem5::VoltageDomain::voltage
double voltage() const
Get the current voltage.
Definition: voltage_domain.hh:70
gem5::VoltageDomain::VoltageDomainStats::voltage
statistics::Value voltage
Stat for reporting voltage of the domain.
Definition: voltage_domain.hh:151
logging.hh
gem5::statistics::Group
Statistics container.
Definition: group.hh:93
gem5::CheckpointOut
std::ostream CheckpointOut
Definition: serialize.hh:66
trace.hh
gem5::VoltageDomain
A VoltageDomain is used to group clock domains that operate under the same voltage.
Definition: voltage_domain.hh:56
fatal_if
#define fatal_if(cond,...)
Conditional fatal macro that checks the supplied condition and only causes a fatal error if the condi...
Definition: logging.hh:225
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: decoder.cc:40
gem5::VoltageDomain::numVoltages
uint32_t numVoltages() const
Definition: voltage_domain.hh:87

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