diff options
author | Vincent Palatin <vpalatin@chromium.org> | 2011-12-07 18:58:43 +0000 |
---|---|---|
committer | Vincent Palatin <vpalatin@chromium.org> | 2011-12-07 19:10:02 +0000 |
commit | e24fa592d2a215d8ae67917c1d89e68cdf847a03 (patch) | |
tree | 47fbe4c55e7f4089cad7d619eded337da3bae999 /test/timer_calib.py | |
parent | 6396911897e4cd40f52636d710cee2865acf15e3 (diff) | |
download | chrome-ec-e24fa592d2a215d8ae67917c1d89e68cdf847a03.tar.gz |
Initial sources import 3/3
source files mainly done by Vincent.
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Change-Id: Ic2d1becd400c9b4b4a14d4a243af1bdf77d9c1e2
Diffstat (limited to 'test/timer_calib.py')
-rw-r--r-- | test/timer_calib.py | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/test/timer_calib.py b/test/timer_calib.py new file mode 100644 index 0000000000..d62e9f7634 --- /dev/null +++ b/test/timer_calib.py @@ -0,0 +1,54 @@ +# Copyright (c) 2011 The Chromium OS Authors. All rights reserved. +# Use of this source code is governed by a BSD-style license that can be +# found in the LICENSE file. +# +# Check timers behavior +# + +import time + +def one_pass(helper): + helper.wait_output("=== Timer calibration ===") + res = helper.wait_output("back-to-back get_time : (?P<lat>[0-9]+) us", + use_re=True)["lat"] + minlat = int(res) + helper.trace("get_time latency %d us\n" % minlat) + + helper.wait_output("sleep 1s") + t0 = time.time() + second = helper.wait_output("done. delay = (?P<second>[0-9]+) us", + use_re=True)["second"] + t1 = time.time() + secondreal = t1 - t0 + secondlat = int(second) - 1000000 + helper.trace("1s timer latency %d us / real time %f s\n" % (secondlat, + secondreal)) + + + us = {} + for pow2 in range(7): + delay = 1 << (7-pow2) + us[delay] = helper.wait_output("%d us => (?P<us>[0-9]+) us" % delay, + use_re=True)["us"] + helper.wait_output("Done.") + + return minlat, secondlat, secondreal + + +def test(helper): + one_pass(helper) + + helper.ec_command("reboot") + helper.wait_output("--- Chrome EC initialized! ---") + + # get the timing results on the second pass + # to avoid binary translation overhead + minlat, secondlat, secondreal = one_pass(helper) + + # check that the timings somewhat make sense + if minlat > 220 or secondlat > 500 or abs(secondreal-1.0) > 0.200: + helper.fail("imprecise timings " + + "(get_time %d us sleep %d us / real time %.3f s)" % + (minlat, secondlat, secondreal)) + + return True # PASS ! |