The NXP QN908x CPU family is a Cortex-M4F CPU with integrated USB,
Bluetooth Low Energy and in some variants NFC. This patch implements the
first steps for having support for this CPU.
While the QN908x can be considered the successor of similar chips from
NXP like the KW41Z when looking at the feature set, the internal
architecture, boot image format and CPU peripherals don't match those
in the Kinetis line. Therefore, this patch creates a new directory for
just the QN908x chip under cpu/qn908x.
The minimal set of peripherals are implemented in this patch to allow
the device to boot and enable a GPIO: the gpio and wdt peripheral
modules only.
The wdt driver is required to boot and disable the wdt. On reset, the
wdt is disabled by the chip, however the QN908x bootloader stored in
the internal ROM enables the wdt and sets a timer to reboot after 10
seconds, therefore it is needed to disable the wdt in RIOT OS soon
after booting. This patch sets it up such that when no periph_wdt module
is used the Watchdog is disabled, but if the periph_wdt is used it must
be configured (initialized) within the first 10 seconds.
Tests performed:
Defined a custom board for this CPU and compiled a simple application
that blinks some LEDs. Manually tested with periph_wdt and with
periph_wdt_cb as well.
In preparation for adding support for the QN908x cpus, this patch adds
a pristine copy of the vendor SDK files needed for initial support.
The only modification to these files is to add '#ifdef __cplusplus'
guards to all the header files, even if not needed or already
present as '#if defined(__cplusplus)', to make sure
./dist/tools/externc/check.sh check passes.
These files are located under vendor/ directories (both
cpu/qn908x/include/vendor/ and cpu/qn908x/vendor/) and are part of NXP's
SDK for the QN908x family available for download from:
https://mcuxpresso.nxp.com/en/builder
The files included in these vendor/ directories are released by NXP
under an Open Source license as described in each file, but only the
files used by the next patch are included here.
