From 0c45c77b8aeac0c3c5a0b5ea13a44ee478b51fdb Mon Sep 17 00:00:00 2001 From: Gaurav Jain Date: Fri, 15 Apr 2022 16:40:49 +0530 Subject: [PATCH] i.MX6SX: crypto/fsl: fix entropy delay value RNG Hardware error is reported due to incorrect entropy delay rng self test are run to determine the correct ent_dly. test is executed with different voltage and temperature to identify the worst case value for ent_dly. after adding a margin value(1000), ent_dly should be at least 12000. Signed-off-by: Gaurav Jain Reviewed-by: Fabio Estevam --- drivers/crypto/fsl/jr.c | 11 ++++++++++- include/fsl_sec.h | 6 +++++- 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/crypto/fsl/jr.c b/drivers/crypto/fsl/jr.c index 1d951cf..85a3dac 100644 --- a/drivers/crypto/fsl/jr.c +++ b/drivers/crypto/fsl/jr.c @@ -623,7 +623,7 @@ static void kick_trng(int ent_delay, ccsr_sec_t *sec) static int rng_init(uint8_t sec_idx, ccsr_sec_t *sec) { - int ret, gen_sk, ent_delay = RTSDCTL_ENT_DLY_MIN; + int ret, gen_sk, ent_delay = RTSDCTL_ENT_DLY; struct rng4tst __iomem *rng = (struct rng4tst __iomem *)&sec->rng; u32 inst_handles; @@ -652,6 +652,15 @@ static int rng_init(uint8_t sec_idx, ccsr_sec_t *sec) * the RNG. */ ret = instantiate_rng(sec_idx, sec, gen_sk); + /* + * entropy delay is calculated via self-test method. + * self-test are run across different volatge, temp. + * if worst case value for ent_dly is identified, + * loop can be skipped for that platform. + */ + if (IS_ENABLED(CONFIG_MX6SX)) + break; + } while ((ret == -1) && (ent_delay < RTSDCTL_ENT_DLY_MAX)); if (ret) { printf("SEC%u: Failed to instantiate RNG\n", sec_idx); diff --git a/include/fsl_sec.h b/include/fsl_sec.h index 7b6e3e2..d57c4ca 100644 --- a/include/fsl_sec.h +++ b/include/fsl_sec.h @@ -48,7 +48,11 @@ struct rng4tst { u32 rtmctl; /* misc. control register */ u32 rtscmisc; /* statistical check misc. register */ u32 rtpkrrng; /* poker range register */ -#define RTSDCTL_ENT_DLY_MIN 3200 +#ifdef CONFIG_MX6SX +#define RTSDCTL_ENT_DLY 12000 +#else +#define RTSDCTL_ENT_DLY 3200 +#endif #define RTSDCTL_ENT_DLY_MAX 12800 union { u32 rtpkrmax; /* PRGM=1: poker max. limit register */ -- 2.7.4