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-ga...
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.