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Commit dd36037d authored by Fabio Estevam's avatar Fabio Estevam Committed by Greg Kroah-Hartman
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crypto: caam - fix i.MX6SX entropy delay value

commit 4ee4cdad upstream.

Since commit 358ba762 ("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: 358ba762

 ("crypto: caam - enable prediction resistance in HRWNG")
Signed-off-by: default avatarFabio Estevam <festevam@denx.de>
Reviewed-by: default avatarHoria Geantă <horia.geanta@nxp.com>
Reviewed-by: default avatarVabhav Sharma <vabhav.sharma@nxp.com>
Reviewed-by: default avatarGaurav Jain <gaurav.jain@nxp.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d8fdb4b2
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