Re: [PATCH v2 2/3] hwrng: starfive - Add TRNG driver for StarFive SoC

From: Herbert Xu
Date: Sun Jan 08 2023 - 23:00:56 EST


On Mon, Jan 09, 2023 at 03:41:14AM +0000, JiaJie Ho wrote:
>
> The average wait time is around 20 microseconds.
> I measured from writel cmd to wait_for_completion done.

Do you know of an upper bound? E.g., if we limit it to 40us how
many requests would fail on average?

Having a maximum delay of 40us would be OK with wait == 0. So
you could implement it in a way such that if the wait time exceeded
40us then you return if wait == 0, otherwise you can wait longer.

Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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