[PATCH] Added Getentropy() support to beagle BSP

[Sebastian Huber]

On 15/03/18 08:13, Udit agarwal wrote:
> Oh yes, i think i misinterpreted your previous suggestion of 
> surrounding the while loop by mutex, it should be the outer while 
> loop. some thing like this?:
> while (n > 0) {
>         uint32_t random;
>         size_t copy;
>
>         rtems_mutex_lock(&atsam_trng_mutex);

Now you correctly use the mutex to produce 32-bits of random data. 
Currently the likely user of getrandom() is

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;a=blob;f=newlib/libc/stdlib/arc4random.c;h=3cccc3ed46a5e9e756d4e216cb7686589eb60993;hb=HEAD#l89

So, you need 12 mutex lock/unlock operations for this. I would protect 
the while (n > 0) loop with a single mutex lock/unlock.

-- 
Sebastian Huber, embedded brains GmbH

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