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

Herbert Xu herbert at gondor.apana.org.au
Sun Jan 8 20:00:20 PST 2023


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 at gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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