2 * Copyright (c) 2012 ARM Limited
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37 * Authors: Vasileios Spiliopoulos
41 #ifndef __SIM_VOLTAGE_DOMAIN_HH__
42 #define __SIM_VOLTAGE_DOMAIN_HH__
46 #include "base/statistics.hh"
47 #include "params/VoltageDomain.hh"
48 #include "sim/clock_domain.hh"
49 #include "sim/sim_object.hh"
52 * A VoltageDomain is used to group clock domains that operate under
53 * the same voltage. The class provides methods for setting and
54 * getting the voltage.
56 class VoltageDomain : public SimObject
60 typedef VoltageDomainParams Params;
61 VoltageDomain(const Params *p);
63 typedef SrcClockDomain::PerfLevel PerfLevel;
66 * Get the current voltage.
68 * @return Voltage of the domain
70 double voltage() const { return voltageOpPoints[_perfLevel]; }
73 * Get the voltage at specified performance level.
75 * @param perf_level Performance level for which the voltage is requested
76 * @return Voltage of the domain at specified performance level
78 double voltage(PerfLevel perf_level) const
80 chatty_assert(perf_level < numVoltages(), "VoltageDomain %s "\
81 "request for voltage perf level %u is outside "\
82 "of numVoltages %u", name(), perf_level,
84 return voltageOpPoints[perf_level];
87 uint32_t numVoltages() const { return (uint32_t)voltageOpPoints.size(); }
90 * Set the voltage point of the domain.
91 * @param Voltage value to be set
93 void perfLevel(PerfLevel perf_level);
96 * Get the voltage point of the domain.
97 * @param Voltage value to be set
99 PerfLevel perfLevel() const { return _perfLevel; }
102 * Register a SrcClockDomain with this voltage domain.
103 * @param src_clock_domain The SrcClockDomain to register.
105 void registerSrcClockDom(SrcClockDomain *src_clock_dom) {
106 assert(src_clock_dom->voltageDomain() == this);
107 srcClockChildren.push_back(src_clock_dom);
111 * Startup has all SrcClockDomains registered with this voltage domain, so
112 * try to make sure that all perf level requests from them are met.
117 * Recomputes the highest (fastest, i.e., numerically lowest) requested
118 * performance level of all associated clock domains, and updates the
119 * performance level of this voltage domain to match. This means that for
120 * two connected clock domains, one fast and one slow, the voltage domain
121 * will provide the voltage associated with the fast DVFS operation point.
122 * Must be called whenever a clock domain decides to swtich its performance
125 * @return True, if the voltage was actually changed.
127 bool sanitiseVoltages();
131 void serialize(std::ostream &os);
132 void unserialize(Checkpoint *cp, const std::string §ion);
134 typedef std::vector<double> Voltages;
136 * List of possible minimum voltage at each of the frequency operational
137 * points, should be in descending order and same size as freqOpPoints.
138 * An empty list corresponds to default voltage specified for the voltage
139 * domain its clock domain belongs. The same voltage is applied for each
140 * freqOpPoints, overall implying NO DVS
142 const Voltages voltageOpPoints;
143 PerfLevel _perfLevel;
146 * Stat for reporting voltage of the domain
148 Stats::Value currentVoltage;
151 * List of associated SrcClockDomains that are connected to this voltage
154 typedef std::vector<SrcClockDomain *> SrcClockChildren;
155 SrcClockChildren srcClockChildren;