From: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Subject: Re: [PATCH 3/3] hwrng: msm - Add support for prng v2
Date: Fri, 22 Jun 2018 11:27:59 +0300
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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>,
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To: Herbert Xu <herbert@gondor.apana.org.au>,
        Stanimir Varbanov <stanimir.varbanov@linaro.org>
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Hi Herbert,

On 06/21/2018 02:53 PM, Herbert Xu wrote:
> On Thu, Jun 21, 2018 at 02:27:10PM +0300, Stanimir Varbanov wrote:
>>
>> OK, I just wanted to say that it is _not_ PRNG and the register names
>> gives us wrong impression.
> 
> So does it generate one bit of output for each bit of hardware-
> generated entropy like /dev/random? Or does it use a hardware-
> generated seed to power a PRNG?

I believe it is the second one. Isn't the second one SP 800-90A?

-- 
regards,
Stan