From c4065517362ae9132ceaaec4103ed5ad6c9cfe92 Mon Sep 17 00:00:00 2001 From: Alex Porosanu Date: Tue, 5 May 2015 16:48:35 +0300 Subject: drivers/crypto/fsl: enable raw data instead of von Neumann data The sampling of the oscillator can be done in multiple modes for generating the entropy value. By default, this is set to von Neumann. This patch changes the sampling to raw data, since it has been discovered that the generated entropy has a better 'quality'. Signed-off-by: Alex Porosanu Acked-by: Ruchika Gupta Reviewed-by: York Sun --- drivers/crypto/fsl/jr.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'drivers/crypto/fsl') diff --git a/drivers/crypto/fsl/jr.c b/drivers/crypto/fsl/jr.c index aa527ec..3560668 100644 --- a/drivers/crypto/fsl/jr.c +++ b/drivers/crypto/fsl/jr.c @@ -408,8 +408,17 @@ static void kick_trng(int ent_delay) sec_out32(&rng->rtfreqmin, ent_delay >> 2); /* disable maximum frequency count */ sec_out32(&rng->rtfreqmax, RTFRQMAX_DISABLE); + /* read the control register */ + val = sec_in32(&rng->rtmctl); + /* + * select raw sampling in both entropy shifter + * and statistical checker + */ + sec_setbits32(&val, RTMCTL_SAMP_MODE_RAW_ES_SC); /* put RNG4 into run mode */ - sec_clrbits32(&rng->rtmctl, RTMCTL_PRGM); + sec_clrbits32(&val, RTMCTL_PRGM); + /* write back the control register */ + sec_out32(&rng->rtmctl, val); } static int rng_init(void) -- cgit v1.1