| # Copyright 2015 ARM Limited |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); |
| # you may not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| # |
| from __future__ import division |
| import os |
| import csv |
| import signal |
| import tempfile |
| import struct |
| import subprocess |
| |
| from devlib.instrument import Instrument, CONTINUOUS, MeasurementsCsv |
| from devlib.exception import HostError |
| from devlib.utils.misc import which |
| |
| |
| class EnergyProbeInstrument(Instrument): |
| |
| mode = CONTINUOUS |
| |
| def __init__(self, target, resistor_values, |
| labels=None, |
| device_entry='/dev/ttyACM0', |
| ): |
| super(EnergyProbeInstrument, self).__init__(target) |
| self.resistor_values = resistor_values |
| if labels is not None: |
| self.labels = labels |
| else: |
| self.labels = ['PORT_{}'.format(i) |
| for i in xrange(len(resistor_values))] |
| self.device_entry = device_entry |
| self.caiman = which('caiman') |
| if self.caiman is None: |
| raise HostError('caiman must be installed on the host ' |
| '(see https://github.com/ARM-software/caiman)') |
| self.attributes_per_sample = 3 |
| self.bytes_per_sample = self.attributes_per_sample * 4 |
| self.attributes = ['power', 'voltage', 'current'] |
| self.command = None |
| self.raw_output_directory = None |
| self.process = None |
| self.sample_rate_hz = 10000 # Determined empirically |
| self.raw_data_file = None |
| |
| for label in self.labels: |
| for kind in self.attributes: |
| self.add_channel(label, kind) |
| |
| def reset(self, sites=None, kinds=None, channels=None): |
| super(EnergyProbeInstrument, self).reset(sites, kinds, channels) |
| self.raw_output_directory = tempfile.mkdtemp(prefix='eprobe-caiman-') |
| parts = ['-r {}:{} '.format(i, int(1000 * rval)) |
| for i, rval in enumerate(self.resistor_values)] |
| rstring = ''.join(parts) |
| self.command = '{} -d {} -l {} {}'.format(self.caiman, self.device_entry, rstring, self.raw_output_directory) |
| self.raw_data_file = None |
| |
| def start(self): |
| self.logger.debug(self.command) |
| self.process = subprocess.Popen(self.command, |
| stdout=subprocess.PIPE, |
| stderr=subprocess.PIPE, |
| stdin=subprocess.PIPE, |
| preexec_fn=os.setpgrp, |
| shell=True) |
| |
| def stop(self): |
| self.process.poll() |
| if self.process.returncode is not None: |
| stdout, stderr = self.process.communicate() |
| raise HostError( |
| 'Energy Probe: Caiman exited unexpectedly with exit code {}.\n' |
| 'stdout:\n{}\nstderr:\n{}'.format(self.process.returncode, |
| stdout, stderr)) |
| os.killpg(self.process.pid, signal.SIGINT) |
| |
| def get_data(self, outfile): # pylint: disable=R0914 |
| 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] |
| |
| num_of_ports = len(self.resistor_values) |
| struct_format = '{}I'.format(num_of_ports * self.attributes_per_sample) |
| not_a_full_row_seen = False |
| self.raw_data_file = os.path.join(self.raw_output_directory, '0000000000') |
| |
| self.logger.debug('Parsing raw data file: {}'.format(self.raw_data_file)) |
| with open(self.raw_data_file, 'rb') as bfile: |
| with open(outfile, 'wb') as wfh: |
| writer = csv.writer(wfh) |
| writer.writerow(active_channels) |
| while True: |
| data = bfile.read(num_of_ports * self.bytes_per_sample) |
| if data == '': |
| break |
| try: |
| unpacked_data = struct.unpack(struct_format, data) |
| row = [unpacked_data[i] / 1000 for i in active_indexes] |
| writer.writerow(row) |
| except struct.error: |
| if not_a_full_row_seen: |
| self.logger.warn('possibly missaligned caiman raw data, row contained {} bytes'.format(len(data))) |
| continue |
| else: |
| not_a_full_row_seen = True |
| return MeasurementsCsv(outfile, self.active_channels, self.sample_rate_hz) |
| |
| def get_raw(self): |
| return [self.raw_data_file] |