zephyr/tests/kernel/timer/timer_behavior/pytest/test_timer.py
Dmitrii Golovanov 889950843f tests: timer: behavior_external: fix MAX_STD_DEV
Fix `MAX_STD_DEV` calculation at the timer behavior external test.

Signed-off-by: Dmitrii Golovanov <dmitrii.golovanov@intel.com>
2024-08-09 08:37:14 -04:00

108 lines
4.8 KiB
Python
Executable File

# Copyright (c) 2023-2024 Intel Corporation
#
# SPDX-License-Identifier: Apache-2.0
import logging
from math import ceil
from twister_harness import DeviceAdapter
logger = logging.getLogger(__name__)
def do_analysis(test, stats, stats_count, config, sys_clock_hw_cycles_per_sec):
logger.info('====================================================')
logger.info(f'periodic timer behaviour using {test} mechanism:')
test_period = int(config['TIMER_TEST_PERIOD'])
test_samples = int(config['TIMER_TEST_SAMPLES'])
seconds = (test_period * test_samples) / 1_000_000
periods_sec = test_period / 1_000_000
ticks_per_sec = int(config['SYS_CLOCK_TICKS_PER_SEC'])
periods_tick = ceil(ticks_per_sec * periods_sec)
expected_period = test_period * sys_clock_hw_cycles_per_sec / 1_000_000
cyc_per_tick = sys_clock_hw_cycles_per_sec / ticks_per_sec
expected_period_drift = ((periods_tick * cyc_per_tick - expected_period) /
sys_clock_hw_cycles_per_sec * 1_000_000)
expected_total_drift = expected_period_drift * test_samples / 1_000_000
period_max_drift = (int(config['TIMER_EXTERNAL_TEST_PERIOD_MAX_DRIFT_PPM'])
/ 1_000_000)
min_bound = (test_period - period_max_drift * test_period +
expected_period_drift) / 1_000_000
max_bound = (test_period + period_max_drift * test_period +
expected_period_drift) / 1_000_000
min_cyc = 1. / sys_clock_hw_cycles_per_sec
max_stddev = int(config['TIMER_TEST_MAX_STDDEV']) / 1_000_000
# Max STDDEV cannot be lower than clock single cycle
max_stddev = max(min_cyc, max_stddev)
max_drift_ppm = int(config['TIMER_EXTERNAL_TEST_MAX_DRIFT_PPM'])
time_diff = stats['total_time'] - seconds - expected_total_drift
logger.info(f'min: {stats["min"] * 1_000_000:.6f} us')
logger.info(f'max: {stats["max"] * 1_000_000:.6f} us')
logger.info(f'mean: {stats["mean"] * 1_000_000:.6f} us')
logger.info(f'variance: {stats["var"] * 1_000_000:.6f} us')
logger.info(f'stddev: {stats["stddev"] * 1_000_000:.6f} us')
logger.info(f'total time: {stats["total_time"] * 1_000_000:.6f} us')
logger.info(f'expected drift: {seconds * max_drift_ppm} us')
logger.info(f'real drift: {time_diff * 1_000_000:.6f} us')
logger.info('====================================================')
logger.info('RECORD: {'
f'"testcase":"jitter_drift_timer"'
f', "mechanism":"{test}_external", "stats_count": {stats_count}, ' +
', '.join(['"{}_us":{:.6f}'.format(k, v * 1_000_000) for k,v in stats.items()]) +
f', "expected_total_time_us":{seconds * 1_000_000:.6f}'
f', "expected_total_drift_us":{seconds * max_drift_ppm:.6f}'
f', "total_drift_us": {time_diff * 1_000_000:.6f}'
f', "min_bound_us":{min_bound * 1_000_000:.6f}'
f', "max_bound_us":{max_bound * 1_000_000:.6f}'
f', "expected_period_cycles":{expected_period:.0f}'
f', "MAX_STD_DEV":{max_stddev * 1_000_000:.0f}'
f', "sys_clock_hw_cycles_per_sec":{sys_clock_hw_cycles_per_sec}, ' +
', '.join(['"CONFIG_{}":{}'.format(k, str(config[k]).rstrip()) for k in [
'SYS_CLOCK_HW_CYCLES_PER_SEC',
'SYS_CLOCK_TICKS_PER_SEC',
'TIMER_TEST_PERIOD',
'TIMER_TEST_SAMPLES',
'TIMER_EXTERNAL_TEST_PERIOD_MAX_DRIFT_PPM',
'TIMER_EXTERNAL_TEST_MAX_DRIFT_PPM'
]
]) + '}'
)
assert stats['stddev'] < max_stddev
assert stats['min'] >= min_bound
assert stats['max'] <= max_bound
assert abs(time_diff) < seconds * max_drift_ppm / 1_000_000
def wait_sync_point(dut: DeviceAdapter, point):
dut.readlines_until(regex=f"===== {point} =====")
def test_flash(dut: DeviceAdapter, tool, tool_options, config,
sys_clock_hw_cycles_per_sec):
tool = __import__(tool)
test_period = int(config['TIMER_TEST_PERIOD'])
test_samples = int(config['TIMER_TEST_SAMPLES'])
seconds = (test_period * test_samples) / 1_000_000
tests = ["builtin", "startdelay"]
for test in tests:
wait_sync_point(dut, test)
stats, stats_count = tool.run(seconds, tool_options)
assert stats_count
do_analysis(test, stats, stats_count, config, sys_clock_hw_cycles_per_sec)
# Let the running test's image output to be fully captured from device.
dut.readlines()