Re: [PATCH v1] crypto: caam - set hwrng quality level

From: Oleksij Rempel
Date: Wed Jul 19 2017 - 12:33:01 EST


On Wed, Jul 19, 2017 at 12:49:47PM +0000, Horia GeantÄ wrote:
> On 7/19/2017 10:45 AM, Oleksij Rempel wrote:
> > According documentation, it is NIST certified TRNG.
> > So, set high quality to let the HWRNG framework automatically use it.
> >
> > Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
> > ---
> > drivers/crypto/caam/caamrng.c | 6 ++++++
> > 1 file changed, 6 insertions(+)
> >
> > diff --git a/drivers/crypto/caam/caamrng.c b/drivers/crypto/caam/caamrng.c
> > index 41398da3edf4..684c0bc88dfd 100644
> > --- a/drivers/crypto/caam/caamrng.c
> > +++ b/drivers/crypto/caam/caamrng.c
> > @@ -292,10 +292,16 @@ static int caam_init_rng(struct caam_rng_ctx *ctx, struct device *jrdev)
> > return 0;
> > }
> >
> > +/*
> > + * hwrng register struct
> > + * The trng is suppost to have 100% entropy, and thus
> > + * we register with a very high quality value.
> > + */
> > static struct hwrng caam_rng = {
> > .name = "rng-caam",
> > .cleanup = caam_cleanup,
> > .read = caam_read,
> > + .quality = 999,
>
> Why not 1024, i.e. where is 999 coming from?

It comes from s390-trng.c driver.
Should I use 1024 instead?

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