Using find_package to locate Zephyr.
Old behavior was to use $ENV{ZEPHYR_BASE} for inclusion of boiler plate
code.
Whenever an automatic run of CMake happend by the build system / IDE
then it was required that ZEPHYR_BASE was defined.
Using ZEPHYR_BASE only to locate the Zephyr package allows CMake to
cache the base variable and thus allowing subsequent invocation even
if ZEPHYR_BASE is not set in the environment.
It also removes the risk of strange build results if a user switchs
between different Zephyr based project folders and forgetting to reset
ZEPHYR_BASE before running ninja / make.
Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>
MetaIRQs are described in docs and exercised in tests, but there's no
sample explaining how they are intended to be used to perform
interrupt bottom half processing.
This simple tool spawns a set of worker threads at different
priorities (some cooperative) which process "messages" (which require
CPU time to handle) received from a fake "device" implemented with
timer interrupts. The device hands off the events directly to a
MetaIRQ thread which is expected to parse and dispatch them to the
worker threads.
The test demonstrates that no matter the state of the system, the
MetaIRQ thread always runs synchronously when woken by the ISR and is
able to preempt all worker threads to do its job.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
