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Date:   Fri, 29 Apr 2022 13:50:02 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Fabio Estevam <festevam@gmail.com>
Cc:     horia.geanta@nxp.com, gaurav.jain@nxp.com, V.Sethi@nxp.com,
        linux-crypto@vger.kernel.org, Fabio Estevam <festevam@denx.de>,
        stable@vger.kernel.org
Subject: Re: [PATCH v5] crypto: caam - fix i.MX6SX entropy delay value
Message-ID: <Ymt8ioIe0UU1NskR@gondor.apana.org.au>
References: <20220420120601.1015362-1-festevam@gmail.com>
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On Wed, Apr 20, 2022 at 09:06:01AM -0300, Fabio Estevam wrote:
> From: Fabio Estevam <festevam@denx.de>
> 
> Since commit 358ba762d9f1 ("crypto: caam - enable prediction resistance
> in HRWNG") the following CAAM errors can be seen on i.MX6SX:
> 
> caam_jr 2101000.jr: 20003c5b: CCB: desc idx 60: RNG: Hardware error
> hwrng: no data available
> 
> This error is due to an incorrect entropy delay for i.MX6SX.
> 
> Fix it by increasing the minimum entropy delay for i.MX6SX
> as done in U-Boot:
> https://patchwork.ozlabs.org/project/uboot/patch/20220415111049.2565744-1-gaurav.jain@nxp.com/
> 
> As explained in the U-Boot patch:
> 
> "RNG self tests are run to determine the correct entropy delay.
> Such tests are executed with different voltages and temperatures to identify
> the worst case value for the entropy delay. For i.MX6SX, it was determined
> that after adding a margin value of 1000 the minimum entropy delay should be
> at least 12000."
> 
> Cc: <stable@vger.kernel.org>
> Fixes: 358ba762d9f1 ("crypto: caam - enable prediction resistance in HRWNG") 
> Signed-off-by: Fabio Estevam <festevam@denx.de>
> Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
> ---
> Changes since v4:
> - Change the function name to needs_entropy_delay_adjustment() - Vabhav
> - Improve the commit log by adding the explanation from the U-Boot
> patch - Vabhav
> 
>  drivers/crypto/caam/ctrl.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)

Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt