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-rw-r--r--src/arch/alpha/tlb.cc2
-rw-r--r--src/arch/mips/tlb.cc2
-rw-r--r--src/arch/power/tlb.cc2
-rw-r--r--src/cpu/testers/memtest/memtest.cc2
-rw-r--r--src/dev/arm/flash_device.cc2
-rw-r--r--src/dev/arm/hdlcd.cc2
-rw-r--r--src/dev/arm/ufs_device.cc2
-rw-r--r--src/mem/probes/stack_dist.cc2
-rw-r--r--src/mem/ruby/network/garnet/BaseGarnetNetwork.cc2
-rw-r--r--src/mem/ruby/network/garnet/fixed-pipeline/Router_d.cc2
-rw-r--r--src/mem/ruby/network/simple/SimpleNetwork.cc2
-rw-r--r--src/mem/ruby/network/simple/Switch.cc2
-rw-r--r--src/mem/ruby/slicc_interface/AbstractController.cc2
-rw-r--r--src/mem/ruby/structures/CacheMemory.cc2
-rw-r--r--src/mem/ruby/structures/Prefetcher.cc2
-rw-r--r--src/mem/ruby/system/RubySystem.hh5
-rw-r--r--src/mem/ruby/system/Sequencer.cc2
-rwxr-xr-xsrc/mem/snoop_filter.cc2
-rw-r--r--src/sim/ClockedObject.py29
-rw-r--r--src/sim/SConscript1
-rw-r--r--src/sim/clock_domain.cc2
-rw-r--r--src/sim/clocked_object.cc177
-rw-r--r--src/sim/clocked_object.hh59
-rw-r--r--src/sim/voltage_domain.cc2
24 files changed, 305 insertions, 4 deletions
diff --git a/src/arch/alpha/tlb.cc b/src/arch/alpha/tlb.cc
index 3360b34c5..fcd2b518b 100644
--- a/src/arch/alpha/tlb.cc
+++ b/src/arch/alpha/tlb.cc
@@ -76,6 +76,8 @@ TLB::~TLB()
void
TLB::regStats()
{
+ BaseTLB::regStats();
+
fetch_hits
.name(name() + ".fetch_hits")
.desc("ITB hits");
diff --git a/src/arch/mips/tlb.cc b/src/arch/mips/tlb.cc
index d2aa5ad70..340c83021 100644
--- a/src/arch/mips/tlb.cc
+++ b/src/arch/mips/tlb.cc
@@ -226,6 +226,8 @@ TLB::unserialize(CheckpointIn &cp)
void
TLB::regStats()
{
+ BaseTLB::regStats();
+
read_hits
.name(name() + ".read_hits")
.desc("DTB read hits")
diff --git a/src/arch/power/tlb.cc b/src/arch/power/tlb.cc
index edfb4f453..90a341d85 100644
--- a/src/arch/power/tlb.cc
+++ b/src/arch/power/tlb.cc
@@ -223,6 +223,8 @@ TLB::unserialize(CheckpointIn &cp)
void
TLB::regStats()
{
+ BaseTLB::regStats();
+
read_hits
.name(name() + ".read_hits")
.desc("DTB read hits")
diff --git a/src/cpu/testers/memtest/memtest.cc b/src/cpu/testers/memtest/memtest.cc
index b0dde6d27..223532088 100644
--- a/src/cpu/testers/memtest/memtest.cc
+++ b/src/cpu/testers/memtest/memtest.cc
@@ -197,6 +197,8 @@ MemTest::completeRequest(PacketPtr pkt, bool functional)
void
MemTest::regStats()
{
+ MemObject::regStats();
+
using namespace Stats;
numReadsStat
diff --git a/src/dev/arm/flash_device.cc b/src/dev/arm/flash_device.cc
index 60c910626..297354b65 100644
--- a/src/dev/arm/flash_device.cc
+++ b/src/dev/arm/flash_device.cc
@@ -472,6 +472,8 @@ FlashDevice::getUnknownPages(uint32_t index)
void
FlashDevice::regStats()
{
+ AbstractNVM::regStats();
+
using namespace Stats;
std::string fd_name = name() + ".FlashDevice";
diff --git a/src/dev/arm/hdlcd.cc b/src/dev/arm/hdlcd.cc
index b04de21bf..0f63f23fc 100644
--- a/src/dev/arm/hdlcd.cc
+++ b/src/dev/arm/hdlcd.cc
@@ -97,6 +97,8 @@ HDLcd::~HDLcd()
void
HDLcd::regStats()
{
+ AmbaDmaDevice::regStats();
+
using namespace Stats;
stats.underruns
diff --git a/src/dev/arm/ufs_device.cc b/src/dev/arm/ufs_device.cc
index 07d50903b..fe05b3279 100644
--- a/src/dev/arm/ufs_device.cc
+++ b/src/dev/arm/ufs_device.cc
@@ -774,6 +774,8 @@ UFSHostDeviceParams::create()
void
UFSHostDevice::regStats()
{
+ DmaDevice::regStats();
+
using namespace Stats;
std::string UFSHost_name = name() + ".UFSDiskHost";
diff --git a/src/mem/probes/stack_dist.cc b/src/mem/probes/stack_dist.cc
index a447f49e5..b12c81e2c 100644
--- a/src/mem/probes/stack_dist.cc
+++ b/src/mem/probes/stack_dist.cc
@@ -57,6 +57,8 @@ StackDistProbe::StackDistProbe(StackDistProbeParams *p)
void
StackDistProbe::regStats()
{
+ BaseMemProbe::regStats();
+
const StackDistProbeParams *p(
dynamic_cast<const StackDistProbeParams *>(params()));
assert(p);
diff --git a/src/mem/ruby/network/garnet/BaseGarnetNetwork.cc b/src/mem/ruby/network/garnet/BaseGarnetNetwork.cc
index 1213073e9..2bd2acb9f 100644
--- a/src/mem/ruby/network/garnet/BaseGarnetNetwork.cc
+++ b/src/mem/ruby/network/garnet/BaseGarnetNetwork.cc
@@ -69,6 +69,8 @@ BaseGarnetNetwork::init()
void
BaseGarnetNetwork::regStats()
{
+ Network::regStats();
+
m_flits_received
.init(m_virtual_networks)
.name(name() + ".flits_received")
diff --git a/src/mem/ruby/network/garnet/fixed-pipeline/Router_d.cc b/src/mem/ruby/network/garnet/fixed-pipeline/Router_d.cc
index 97bc1abdd..dab9b7dda 100644
--- a/src/mem/ruby/network/garnet/fixed-pipeline/Router_d.cc
+++ b/src/mem/ruby/network/garnet/fixed-pipeline/Router_d.cc
@@ -158,6 +158,8 @@ Router_d::update_sw_winner(int inport, flit_d *t_flit)
void
Router_d::regStats()
{
+ BasicRouter::regStats();
+
m_buffer_reads
.name(name() + ".buffer_reads")
.flags(Stats::nozero)
diff --git a/src/mem/ruby/network/simple/SimpleNetwork.cc b/src/mem/ruby/network/simple/SimpleNetwork.cc
index 25d0b6f4b..2fc7b6440 100644
--- a/src/mem/ruby/network/simple/SimpleNetwork.cc
+++ b/src/mem/ruby/network/simple/SimpleNetwork.cc
@@ -132,6 +132,8 @@ SimpleNetwork::makeInternalLink(SwitchID src, SwitchID dest, BasicLink* link,
void
SimpleNetwork::regStats()
{
+ Network::regStats();
+
for (MessageSizeType type = MessageSizeType_FIRST;
type < MessageSizeType_NUM; ++type) {
m_msg_counts[(unsigned int) type]
diff --git a/src/mem/ruby/network/simple/Switch.cc b/src/mem/ruby/network/simple/Switch.cc
index 747884f16..78f5b609c 100644
--- a/src/mem/ruby/network/simple/Switch.cc
+++ b/src/mem/ruby/network/simple/Switch.cc
@@ -112,6 +112,8 @@ Switch::getThrottle(LinkID link_number) const
void
Switch::regStats()
{
+ BasicRouter::regStats();
+
for (int link = 0; link < m_throttles.size(); link++) {
m_throttles[link]->regStats(name());
}
diff --git a/src/mem/ruby/slicc_interface/AbstractController.cc b/src/mem/ruby/slicc_interface/AbstractController.cc
index 2a53e53be..be48628e9 100644
--- a/src/mem/ruby/slicc_interface/AbstractController.cc
+++ b/src/mem/ruby/slicc_interface/AbstractController.cc
@@ -76,6 +76,8 @@ AbstractController::resetStats()
void
AbstractController::regStats()
{
+ MemObject::regStats();
+
m_fully_busy_cycles
.name(name() + ".fully_busy_cycles")
.desc("cycles for which number of transistions == max transitions")
diff --git a/src/mem/ruby/structures/CacheMemory.cc b/src/mem/ruby/structures/CacheMemory.cc
index f7c196119..36d109769 100644
--- a/src/mem/ruby/structures/CacheMemory.cc
+++ b/src/mem/ruby/structures/CacheMemory.cc
@@ -488,6 +488,8 @@ CacheMemory::isLocked(Addr address, int context)
void
CacheMemory::regStats()
{
+ SimObject::regStats();
+
m_demand_hits
.name(name() + ".demand_hits")
.desc("Number of cache demand hits")
diff --git a/src/mem/ruby/structures/Prefetcher.cc b/src/mem/ruby/structures/Prefetcher.cc
index ce6d36c04..eef51dcf7 100644
--- a/src/mem/ruby/structures/Prefetcher.cc
+++ b/src/mem/ruby/structures/Prefetcher.cc
@@ -86,6 +86,8 @@ Prefetcher::~Prefetcher()
void
Prefetcher::regStats()
{
+ SimObject::regStats();
+
numMissObserved
.name(name() + ".miss_observed")
.desc("number of misses observed")
diff --git a/src/mem/ruby/system/RubySystem.hh b/src/mem/ruby/system/RubySystem.hh
index 62330e19d..8ebd3494a 100644
--- a/src/mem/ruby/system/RubySystem.hh
+++ b/src/mem/ruby/system/RubySystem.hh
@@ -89,7 +89,10 @@ class RubySystem : public ClockedObject
return m_profiler;
}
- void regStats() override { m_profiler->regStats(name()); }
+ void regStats() override {
+ ClockedObject::regStats();
+ m_profiler->regStats(name());
+ }
void collateStats() { m_profiler->collateStats(); }
void resetStats() override;
diff --git a/src/mem/ruby/system/Sequencer.cc b/src/mem/ruby/system/Sequencer.cc
index dedade3cf..fbaad8407 100644
--- a/src/mem/ruby/system/Sequencer.cc
+++ b/src/mem/ruby/system/Sequencer.cc
@@ -688,6 +688,8 @@ Sequencer::evictionCallback(Addr address)
void
Sequencer::regStats()
{
+ RubyPort::regStats();
+
m_store_waiting_on_load
.name(name() + ".store_waiting_on_load")
.desc("Number of times a store aliased with a pending load")
diff --git a/src/mem/snoop_filter.cc b/src/mem/snoop_filter.cc
index 9d02ed249..9e8f8afb8 100755
--- a/src/mem/snoop_filter.cc
+++ b/src/mem/snoop_filter.cc
@@ -351,6 +351,8 @@ SnoopFilter::updateResponse(const Packet* cpkt, const SlavePort& slave_port)
void
SnoopFilter::regStats()
{
+ SimObject::regStats();
+
totRequests
.name(name() + ".tot_requests")
.desc("Total number of requests made to the snoop filter.");
diff --git a/src/sim/ClockedObject.py b/src/sim/ClockedObject.py
index 2562f1f01..b933ea07a 100644
--- a/src/sim/ClockedObject.py
+++ b/src/sim/ClockedObject.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2012 ARM Limited
+# Copyright (c) 2012, 2015 ARM Limited
# All rights reserved.
#
# The license below extends only to copyright in the software and shall
@@ -39,6 +39,24 @@ from m5.SimObject import SimObject
from m5.params import *
from m5.proxy import *
+# Enumerate set of allowed power states that can be used by a clocked object.
+# The list is kept generic to express a base minimal set.
+# State definition :-
+# Undefined: Invalid state, no power state derived information is available.
+# On: The logic block is actively running and consuming dynamic and leakage
+# energy depending on the amount of processing required.
+# Clk_gated: The clock circuity within the block is gated to save dynamic
+# energy, the power supply to the block is still on and leakage
+# energy is being consumed by the block.
+# Sram_retention: The SRAMs within the logic blocks are pulled into retention
+# state to reduce leakage energy further.
+# Off: The logic block is power gated and is not consuming any energy.
+class PwrState(Enum): vals = ['UNDEFINED',
+ 'ON',
+ 'CLK_GATED',
+ 'SRAM_RETENTION',
+ 'OFF']
+
class ClockedObject(SimObject):
type = 'ClockedObject'
abstract = True
@@ -47,3 +65,12 @@ class ClockedObject(SimObject):
# The clock domain this clocked object belongs to, inheriting the
# parent's clock domain by default
clk_domain = Param.ClockDomain(Parent.clk_domain, "Clock domain")
+
+ # Provide initial power state, should ideally get redefined in startup
+ # routine
+ default_p_state = Param.PwrState("UNDEFINED", "Default Power State")
+
+ p_state_clk_gate_min = Param.Latency('1ns', "Min value of the distribution")
+ p_state_clk_gate_max = Param.Latency('1s', "Max value of the distribution")
+ p_state_clk_gate_bins = Param.Unsigned('20',
+ "# bins in clk gated distribution")
diff --git a/src/sim/SConscript b/src/sim/SConscript
index 3238301ed..e40c43f0c 100644
--- a/src/sim/SConscript
+++ b/src/sim/SConscript
@@ -69,6 +69,7 @@ Source('voltage_domain.cc')
Source('linear_solver.cc')
Source('system.cc')
Source('dvfs_handler.cc')
+Source('clocked_object.cc')
if env['TARGET_ISA'] != 'null':
SimObject('InstTracer.py')
diff --git a/src/sim/clock_domain.cc b/src/sim/clock_domain.cc
index 1ccee7f1d..9865c4d11 100644
--- a/src/sim/clock_domain.cc
+++ b/src/sim/clock_domain.cc
@@ -56,6 +56,8 @@
void
ClockDomain::regStats()
{
+ SimObject::regStats();
+
using namespace Stats;
// Expose the current clock period as a stat for observability in
diff --git a/src/sim/clocked_object.cc b/src/sim/clocked_object.cc
new file mode 100644
index 000000000..9a682a4ce
--- /dev/null
+++ b/src/sim/clocked_object.cc
@@ -0,0 +1,177 @@
+/*
+ * Copyright (c) 2015 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder. You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Akash Bagdia
+ * David Guillen Fandos
+ */
+
+#include "sim/clocked_object.hh"
+
+#include "base/misc.hh"
+
+void
+ClockedObject::serialize(CheckpointOut &cp) const
+{
+ unsigned int currPwrState = (unsigned int)_currPwrState;
+
+ SERIALIZE_SCALAR(currPwrState);
+ SERIALIZE_SCALAR(prvEvalTick);
+}
+
+void
+ClockedObject::unserialize(CheckpointIn &cp)
+{
+ unsigned int currPwrState;
+
+ UNSERIALIZE_SCALAR(currPwrState);
+ UNSERIALIZE_SCALAR(prvEvalTick);
+
+ _currPwrState = Enums::PwrState(currPwrState);
+}
+
+void
+ClockedObject::pwrState(Enums::PwrState p)
+{
+ // Function should ideally be called only when there is a state change
+ if (_currPwrState == p) {
+ warn("ClockedObject: Already in the requested power state, request "\
+ "ignored");
+ return;
+ }
+
+ // No need to compute stats if in the same tick, update state
+ // though. This can happen in cases like a) during start of the
+ // simulation multiple state changes happens in init/startup phase,
+ // b) one takes a decision to migrate state but decides to reverts
+ // back to the original state in the same tick if other conditions
+ // are not met elsewhere. Any state change related stats would have
+ // been recorded on previous call to the pwrState() function.
+ if (prvEvalTick == curTick()) {
+ warn("ClockedObject: More than one power state change request "\
+ "encountered within the same simulation tick");
+ _currPwrState = p;
+ return;
+ }
+
+ // Record stats for previous state.
+ computeStats();
+
+ _currPwrState = p;
+
+ numPwrStateTransitions++;
+}
+
+void
+ClockedObject::computeStats()
+{
+ // Calculate time elapsed from last (valid) state change
+ Tick elapsed_time = curTick() - prvEvalTick;
+
+ pwrStateResidencyTicks[_currPwrState] += elapsed_time;
+
+ // Time spent in CLK_GATED state, this might change depending on
+ // transition to other low power states in respective simulation
+ // objects.
+ if (_currPwrState == Enums::PwrState::CLK_GATED) {
+ pwrStateClkGateDist.sample(elapsed_time);
+ }
+
+ prvEvalTick = curTick();
+}
+
+std::vector<double>
+ClockedObject::pwrStateWeights() const
+{
+ // Get residency stats
+ std::vector<double> ret;
+ Stats::VCounter residencies;
+ pwrStateResidencyTicks.value(residencies);
+
+ // Account for current state too!
+ Tick elapsed_time = curTick() - prvEvalTick;
+ residencies[_currPwrState] += elapsed_time;
+
+ ret.resize(Enums::PwrState::Num_PwrState);
+ for (unsigned i = 0; i < Enums::PwrState::Num_PwrState; i++)
+ ret[i] = residencies[i] /
+ (pwrStateResidencyTicks.total() + elapsed_time);
+
+ return ret;
+}
+
+void
+ClockedObject::regStats()
+{
+ SimObject::regStats();
+
+ using namespace Stats;
+
+ numPwrStateTransitions
+ .name(params()->name + ".numPwrStateTransitions")
+ .desc("Number of power state transitions")
+ ;
+
+ // Each sample is time in ticks
+ unsigned num_bins = std::max(params()->p_state_clk_gate_bins, 10U);
+ pwrStateClkGateDist
+ .init(params()->p_state_clk_gate_min, params()->p_state_clk_gate_max,
+ (params()->p_state_clk_gate_max / num_bins))
+ .name(params()->name + ".pwrStateClkGateDist")
+ .desc("Distribution of time spent in the clock gated state")
+ .flags(pdf)
+ ;
+
+ pwrStateResidencyTicks
+ .init(Enums::PwrState::Num_PwrState)
+ .name(params()->name + ".pwrStateResidencyTicks")
+ .desc("Cumulative time (in ticks) in various power states")
+ ;
+ for (int i = 0; i < Enums::PwrState::Num_PwrState; i++) {
+ pwrStateResidencyTicks.subname(i, Enums::PwrStateStrings[i]);
+ }
+
+ numPwrStateTransitions = 0;
+
+ /**
+ * For every stats dump, the power state residency and other distribution
+ * stats should be computed just before the dump to ensure correct stats
+ * value being reported for current dump window. It avoids things like
+ * having any unreported time spent in a power state to be forwarded to the
+ * next dump window which might have rather unpleasant effects (like
+ * perturbing the distribution stats).
+ */
+ registerDumpCallback(new ClockedObjectDumpCallback(this));
+}
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__
diff --git a/src/sim/voltage_domain.cc b/src/sim/voltage_domain.cc
index b82efda33..61715dfbc 100644
--- a/src/sim/voltage_domain.cc
+++ b/src/sim/voltage_domain.cc
@@ -128,6 +128,8 @@ VoltageDomain::startup() {
void
VoltageDomain::regStats()
{
+ SimObject::regStats();
+
currentVoltage
.method(this, &VoltageDomain::voltage)
.name(params()->name + ".voltage")