diff options
| author | Andrey Smirnov <andrew.smirnov@gmail.com> | 2020-03-19 09:12:30 -0700 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2020-03-30 11:50:49 +1100 |
| commit | 551ce72a78e2c5493fa987410437e54b5f3fdd34 (patch) | |
| tree | 765448391f437ff004f71d84fe27d6c2d78a9a3e /drivers/crypto | |
| parent | 32107e43b505de44ebe1917da2c8c6229acbd509 (diff) | |
crypto: caam - invalidate entropy register during RNG initialization
In order to make sure that we always use non-stale entropy data, change
the code to invalidate entropy register during RNG initialization.
Signed-off-by: Aymen Sghaier <aymen.sghaier@nxp.com>
Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
[andrew.smirnov@gmail.com ported to upstream kernel, rewrote commit msg]
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Horia Geantă <horia.geanta@nxp.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Iuliana Prodan <iuliana.prodan@nxp.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-imx@nxp.com
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/crypto')
| -rw-r--r-- | drivers/crypto/caam/ctrl.c | 11 | ||||
| -rw-r--r-- | drivers/crypto/caam/regs.h | 3 |
2 files changed, 10 insertions, 4 deletions
diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c index 7f7f2960b0cc..b278471f4013 100644 --- a/drivers/crypto/caam/ctrl.c +++ b/drivers/crypto/caam/ctrl.c @@ -341,8 +341,12 @@ static void kick_trng(struct platform_device *pdev, int ent_delay) ctrl = (struct caam_ctrl __iomem *)ctrlpriv->ctrl; r4tst = &ctrl->r4tst[0]; - /* put RNG4 into program mode */ - clrsetbits_32(&r4tst->rtmctl, 0, RTMCTL_PRGM); + /* + * Setting both RTMCTL:PRGM and RTMCTL:TRNG_ACC causes TRNG to + * properly invalidate the entropy in the entropy register and + * force re-generation. + */ + clrsetbits_32(&r4tst->rtmctl, 0, RTMCTL_PRGM | RTMCTL_ACC); /* * Performance-wise, it does not make sense to @@ -372,7 +376,8 @@ start_rng: * select raw sampling in both entropy shifter * and statistical checker; ; put RNG4 into run mode */ - clrsetbits_32(&r4tst->rtmctl, RTMCTL_PRGM, RTMCTL_SAMP_MODE_RAW_ES_SC); + clrsetbits_32(&r4tst->rtmctl, RTMCTL_PRGM | RTMCTL_ACC, + RTMCTL_SAMP_MODE_RAW_ES_SC); } static int caam_get_era_from_hw(struct caam_ctrl __iomem *ctrl) diff --git a/drivers/crypto/caam/regs.h b/drivers/crypto/caam/regs.h index 05127b70527d..c191e8fd0fa7 100644 --- a/drivers/crypto/caam/regs.h +++ b/drivers/crypto/caam/regs.h @@ -487,7 +487,8 @@ struct rngtst { /* RNG4 TRNG test registers */ struct rng4tst { -#define RTMCTL_PRGM 0x00010000 /* 1 -> program mode, 0 -> run mode */ +#define RTMCTL_ACC BIT(5) /* TRNG access mode */ +#define RTMCTL_PRGM BIT(16) /* 1 -> program mode, 0 -> run mode */ #define RTMCTL_SAMP_MODE_VON_NEUMANN_ES_SC 0 /* use von Neumann data in both entropy shifter and statistical checker */ |