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From: Peter Maydell <peter.maydell@linaro.org>
Date: Tue, 4 Apr 2017 13:09:08 +0100
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Subject: Re: [Qemu-devel] [PATCH v2] hw/misc: Add Exynos4210 Pseudo Random
 Number Generator
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To: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Igor Mitsyanko <i.mitsyanko@gmail.com>, qemu-arm <qemu-arm@nongnu.org>, QEMU Developers <qemu-devel@nongnu.org>

On 18 March 2017 at 19:25, Krzysztof Kozlowski <krzk@kernel.org> wrote:
> Add emulation for Exynos4210 Pseudo Random Number Generator which could
> work on fixed seeds or with seeds provided by True Random Number
> Generator block inside the SoC.
>
> Implement only the fixed seeds part of it in polling mode (no
> interrupts).  Simple testing:
>     # echo "exynos" > /sys/class/misc/hw_random/rng_current
>     # dd if=/dev/hwrng of=/dev/null bs=1 count=16
>
> Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
>
> ---
>
> Changes since v1:
> 1. Use GRand-like functions to fix build on MingW32 (this adds also
>    finalize).
> 2. Add DPRINTF macro.
> 3. Use HWADDR_PRIx and family for printing values.

Is there a data sheet that describes this RNG? I had a quick google
but couldn't find anything in the 4210 manual you can get from Samsung.

In particular I'm not sure we want to use GRand here.

thanks
-- PMM