Current implementation of the xoroshiro depends on the ISR being
triggered when the interrupts is locked. This patch proposes
implementing the init with entropy_get_isr. This implementation
can be called at PRE_KERNEL_2 stage, even when the interrupts
are locked.
Fixes: GH-8199
Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
Not only removes a branch during normal operation, but also ensures
that, by initializing at the PRE_KERNEL_2 stage, and granting
privileges to all threads to the semaphore, this code will work in
early boot situations and in user mode.
This assumes that entropy drivers will all initialize during
PRE_KERNEL_1 stage. All in-tree drivers do that.
Signed-off-by: Leandro Pereira <leandro.pereira@intel.com>
Semaphore state_sem initial count is set to 0 but k_sem_give()
is invoked first in sys_rand32_get() which will block the caller
forever.
Fix the issue by setting the initail count to count_limit.
Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
This adds an implementation of Xoroshiro128+ PRNG, based on the
original implementation at [1]. This pseudorandom number generator
will use the entropy driver to obtain the seed.
While it uses only 128 bits of state, it's pretty robust for non-crypto
safe applications.
[1] http://vigna.di.unimi.it/xorshift/xoroshiro128plus.c
Signed-off-by: Leandro Pereira <leandro.pereira@intel.com>
Adithya Baglody