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Date:   Thu, 11 May 2023 09:43:00 +0200
From:   Martin Kaiser <martin@kaiser.cx>
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     linux-crypto@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/3] hwrng: imx-rngc - use bitfield macros to read fifo
 level
Message-ID: <20230511074300.ocfrmynne7e6wdkj@viti.kaiser.cx>
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 <20230427185357.923412-2-martin@kaiser.cx>
 <ZFx6PXL9LzyDRoER@gondor.apana.org.au>
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Sender: Martin Kaiser <martin@viti.kaiser.cx>
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Thus wrote Herbert Xu (herbert@gondor.apana.org.au):

> On Thu, Apr 27, 2023 at 08:53:55PM +0200, Martin Kaiser wrote:

> > @@ -133,9 +133,7 @@ static int imx_rngc_read(struct hwrng *rng, void *data, size_t max, bool wait)
> >  			break;

> >  		/* how many random numbers are in FIFO? [0-16] */
> > -		level = (status & RNGC_STATUS_FIFO_LEVEL_MASK) >>
> > -			RNGC_STATUS_FIFO_LEVEL_SHIFT;
> > -
> > +		level = FIELD_GET(RNGC_STATUS_FIFO_LEVEL, status);

> Wouldn't it be simpler to just get rid of the shift?

Yes, we're only checking that level > 0, there's no need for the shift.
I'll submit a new version of the patch.

Thanks,
Martin