From: Herbert Xu <herbert@gondor.apana.org.au>
Subject: Re: [PATCH 3/3] hwrng: msm - Add support for prng v2
Date: Thu, 21 Jun 2018 18:15:06 +0800
Message-ID: <20180621101506.rnklbtapvfdev4xb@gondor.apana.org.au>
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 <20180618141259.23141-4-vkoul@kernel.org>
 <20180619142853.wgi5easw4zv6ttrb@gondor.apana.org.au>
 <966e9cd4-70a3-8d54-df0f-16df3df45fb5@linaro.org>
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Cc: Vinod Koul <vinod.koul@linaro.org>, linux-crypto@vger.kernel.org,
        linux-kernel@vger.kernel.org, Matt Mackall <mpm@selenic.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-arm-msm@vger.kernel.org, Vinod Koul <vkoul@kernel.org>
To: Stanimir Varbanov <stanimir.varbanov@linaro.org>
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On Thu, Jun 21, 2018 at 12:56:34PM +0300, Stanimir Varbanov wrote:
>
> > Is this really a pseudo-RNG? If so it needs to be moved over to
> > the algif_rng interface.
> 
> Despite the register name (PRNG_ registers prefix) the IP is using FIPS
> approved algorithm and we can claim that this is true hardware entropy
> generator.

Whether your RNG is a PRNG or not has nothing to do with the
algorithm you use.  No algorithm can generate entropy out of thin
air.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt