The start/stop overhead that might by introduced by ztimer_acquire() and ztimer_release() called during ztimer_set() resp. ztimer_handler() should not be mesured here. It has its own adjustment field.
Furthermore, the overhead mesaurement uses ztimer_now(). It is allowed to called it only after the clock has been acquired.
This allows including C headers from C++. It sadly reduced the
diagnostics on C++ code as well, were there warning may make sense as
unintended side effect. We may be able to drop that later on, when more
C APIs are properly wrapped in native C++ APIs, so that C headers do no
longer need to be compatible with C++ compilers.
Nightlies are failing due to kconfig mismatch.
It would seem this is a result of bringing in the USB stuff.
I assume that this uses ztimer periph_timer as a backend as periph_timer is already selected.
However, kconfig only resolves one and not recursively making it hard to match.
For not a hack is added to override for these boards.
This adds a xtimer_no_ztimer_default that is currently always
selected in Makefile, but that can be switched off in Kconfig.
Removing its inclusion will allow switching the default xtimer
backend to ztimer, while allowing for an easy way back.
This is done to avoid circular dependency, it will currently allow for
ztimer64_xtimer_compat beeing selected as well as xtimer_on_ztimer.
This altough incorrect mimics make, and will be fixed when making
ztimer_xtimer_compat the default xtimer backend
Replace use of C11 atomics with atomic utils. This fixes
> error: address argument to atomic operation must be a pointer to a
> trivially-copyable type ('_Atomic(int) *' invalid)
error when compiling on AVR with LLVM.
The sam0 rtt busy loops for 180us every time an alarm is set or
the counter is read, this propagates and leads to timing errors
on ztimer_msec that are higher than > +-1msec.
The same goes for fe310.
The callback function of `ztimer_periodic` is only expected to have
two states.
So let it return `true` if the timer should keep repeating, `false`
otherwise.
