def __init__(self, target, config_file='./config-aep', keep_raw=False):
super(ArmEnergyProbeInstrument, self).__init__(target)
self.arm_probe = which('arm-probe')
if self.arm_probe is None:
raise HostError('arm-probe must be installed on the host')
#todo detect is config file exist
self.attributes = ['power', 'voltage', 'current']
self.sample_rate_hz = 10000
self.config_file = config_file
self.keep_raw = keep_raw
self.parser = AepParser()
#TODO make it generic
topo = self.parser.topology_from_config(self.config_file)
for item in topo:
if item == 'time':
self.add_channel('timestamp', 'time')
else:
self.add_channel(item, 'power')
class ArmEnergyProbeInstrument(Instrument):
"""
Collects power traces using the ARM Energy Probe.
This instrument requires ``arm-probe`` utility to be installed on the host and be in the PATH.
arm-probe is available here:
``https://git.linaro.org/tools/arm-probe.git``.
Details about how to build and use it is available here:
``https://git.linaro.org/tools/arm-probe.git/tree/README``
ARM energy probe (AEP) device can simultaneously collect power from up to 3 power rails and
arm-probe utility can record data from several AEP devices simultaneously.
To connect the energy probe on a rail, connect the white wire to the pin that is closer to the
Voltage source and the black wire to the pin that is closer to the load (the SoC or the device
you are probing). Between the pins there should be a shunt resistor of known resistance in the
range of 5 to 500 mOhm but the voltage on the shunt resistor must stay smaller than 165mV.
The resistance of the shunt resistors is a mandatory parameter to be set in the ``config`` file.
"""
mode = CONTINUOUS
MAX_CHANNELS = 12 # 4 Arm Energy Probes
def __init__(self, target, config_file='./config-aep', keep_raw=False):
super(ArmEnergyProbeInstrument, self).__init__(target)
self.arm_probe = which('arm-probe')
if self.arm_probe is None:
raise HostError('arm-probe must be installed on the host')
#todo detect is config file exist
self.attributes = ['power', 'voltage', 'current']
self.sample_rate_hz = 10000
self.config_file = config_file
self.keep_raw = keep_raw
self.parser = AepParser()
#TODO make it generic
topo = self.parser.topology_from_config(self.config_file)
for item in topo:
if item == 'time':
self.add_channel('timestamp', 'time')
else:
self.add_channel(item, 'power')
def reset(self, sites=None, kinds=None, channels=None):
super(ArmEnergyProbeInstrument, self).reset(sites, kinds, channels)
self.output_directory = tempfile.mkdtemp(prefix='energy_probe')
self.output_file_raw = os.path.join(self.output_directory, 'data_raw')
self.output_file = os.path.join(self.output_directory, 'data')
self.output_file_figure = os.path.join(self.output_directory,
'summary.txt')
self.output_file_error = os.path.join(self.output_directory,
'error.log')
self.output_fd_error = open(self.output_file_error, 'w')
self.command = 'arm-probe --config {} > {}'.format(
quote(self.config_file), quote(self.output_file_raw))
def start(self):
self.logger.debug(self.command)
self.armprobe = subprocess.Popen(self.command,
stderr=self.output_fd_error,
preexec_fn=os.setpgrp,
shell=True)
def stop(self):
self.logger.debug("kill running arm-probe")
os.killpg(self.armprobe.pid, signal.SIGTERM)
def get_data(self, outfile): # pylint: disable=R0914
self.logger.debug("Parse data and compute consumed energy")
self.parser.prepare(self.output_file_raw, self.output_file,
self.output_file_figure)
self.parser.parse_aep()
self.parser.unprepare()
skip_header = 1
all_channels = [c.label for c in self.list_channels()]
active_channels = [c.label for c in self.active_channels]
active_indexes = [all_channels.index(ac) for ac in active_channels]
with csvreader(self.output_file, delimiter=' ') as reader:
with csvwriter(outfile) as writer:
for row in reader:
if skip_header == 1:
writer.writerow(active_channels)
skip_header = 0
continue
if len(row) < len(active_channels):
continue
# all data are in micro (seconds/watt)
new = [float(row[i]) / 1000000 for i in active_indexes]
writer.writerow(new)
self.output_fd_error.close()
shutil.rmtree(self.output_directory)
return MeasurementsCsv(outfile, self.active_channels,
self.sample_rate_hz)
def get_raw(self):
return [self.output_file_raw]
def teardown(self):
if not self.keep_raw:
if os.path.isfile(self.output_file_raw):
os.remove(self.output_file_raw)