Reimplement atomic code in inline assembly. This can improve
optimisation, and avoids potential architectural problems with using
LDREX/STREX intrinsics.
API further extended:
* Bitwise operations (fetch_and/fetch_or/fetch_xor)
* fetch_add and fetch_sub (like incr/decr, but returning old value -
aligning with C++11)
* compare_exchange_weak
* Explicit memory order specification
* Basic freestanding template overloads for C++
This gives our existing C implementation essentially all the functionality
needed by C++11.
An actual Atomic<T> template based upon these C functions could follow.
The DEVICE_FOO macros are always defined (either 0 or 1).
This patch replaces any instances of a define check on a DEVICE_FOO
macro with value test instead.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
HAL_RNG_GetRandomNumber is a deprecated API and replaced here with
a call to HAL_RNG_GenerateRandomNumber.
Doing so, we also rework the driver to use the 4 bytes returned by a call
to HAL_RNG_GenerateRandomNumber instead of 1 byte out of 4.
HAL_RNG_GenerateRandomNumber was not returning any error code, so now
we can also check the return code.
Martin Kojtal
jeromecoutant
Kevin Bracey
Laurent Meunier
bcostm
Alastair D'Silva
adustm