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Date:   Fri, 6 Jan 2023 09:18:24 +0100
From:   Corentin Labbe <clabbe.montjoie@gmail.com>
To:     Samuel Holland <samuel@sholland.org>
Cc:     Herbert Xu <herbert@gondor.apana.org.au>,
        "David S . Miller" <davem@davemloft.net>,
        Chen-Yu Tsai <wens@csie.org>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Conor Dooley <conor@kernel.org>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-riscv@lists.infradead.org, linux-sunxi@lists.linux.dev
Subject: Re: [PATCH v2 2/3] crypto: sun8i-ce - Add TRNG clock to the D1
 variant
Message-ID: <Y7fZUDSWaZhpL0hc@Red>
References: <20221231220146.646-1-samuel@sholland.org>
 <20221231220146.646-3-samuel@sholland.org>
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Le Sat, Dec 31, 2022 at 04:01:44PM -0600, Samuel Holland a ?crit :
> At least the D1 variant requires a separate clock for the TRNG.
> Without this clock enabled, reading from /dev/hwrng reports:
> 
>    sun8i-ce 3040000.crypto: DMA timeout for TRNG (tm=96) on flow 3
> 
> Experimentation shows that the necessary clock is the SoC's internal
> RC oscillator. This makes sense, as noise from the oscillator can be
> used as a source of entropy.
> 
> Signed-off-by: Samuel Holland <samuel@sholland.org>
> ---
> 

Acked-by: Corentin Labbe <clabbe.montjoie@gmail.com>

Thanks