Use a busy loop with non-blocking Semaphore::wait(0) calls instead of a
single Semaphore::wait(osWaitForever) to improve time measurement
accuracy. Looping in Semaphore::wait(0) prevents the board from entering
sleep or deepsleep modes while waiting for the semaphore. By skipping
the overhead wakeup time, we get more accurate timings.
When the define LPTICKER_DELAY_TICKS is set deep sleep can be randomly
disallowed when using the low power ticker. This is because a Timer
object, which locks deep sleep, is used to protect from back-to-back
writes to lp tickers which can't support that. This causes tests which
assert that deep sleep is allowed to intermittently fail.
To fix this intermittent failure this patch adds the function
sleep_manager_can_deep_sleep_test_check() which checks if deep sleep
is allowed over a duration. It updates all the tests to use
sleep_manager_can_deep_sleep_test_check() rather
than sleep_manager_can_deep_sleep() so the tests work even if deep
sleep is spuriously blocked.
Update the SysTimer test to match the updated API. Changes are:
- increment_tick() renamed to _increment_tick() and explicitly
synchronized
-update_tick() replaced with resume() and a call to suspend() was added
before this
Filip Jagodzinski
Russ Butler
Martin Kojtal
Przemyslaw Stekiel
jeromecoutant
Bartek Szatkowski
Filip Jagodzinski