[PATCH] i.MX6SX: crypto/fsl: fix entropy delay value

[PATCH] i.MX6SX: crypto/fsl: fix entropy delay value

[Gaurav Jain]

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 <gaurav.jain@nxp.com>
---
 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 1d951cf0a6..85a3dac796 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 7b6e3e2c20..d57c4ca820 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 */
-- 
2.25.1

Re: [PATCH] i.MX6SX: crypto/fsl: fix entropy delay value

[Fabio Estevam]

On Fri, Apr 15, 2022 at 8:11 AM Gaurav Jain <gaurav.jain@nxp.com> wrote:
>
> RNG Hardware error is reported due to incorrect entropy delay

Yes, I observe the RNG hardware error in the kernel too.

> 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 <gaurav.jain@nxp.com>
> ---
>  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 1d951cf0a6..85a3dac796 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.

s/volatge/voltage

Reviewed-by: Fabio Estevam <festevam@denx.de>

RE: [PATCH] i.MX6SX: crypto/fsl: fix entropy delay value

[Gaurav Jain]

Hello Stefano

This patch is already merged in kernel https://patchwork.kernel.org/project/linux-crypto/patch/20220420120601.1015362-1-festevam@gmail.com/
Can you help to check and merge this in Uboot as well.

Regards
Gaurav Jain

> -----Original Message-----
> From: Gaurav Jain
> Sent: Friday, April 15, 2022 4:41 PM
> To: Stefano Babic <sbabic@denx.de>; u-boot@lists.denx.de
> Cc: Fabio Estevam <festevam@gmail.com>; Peng Fan <peng.fan@nxp.com>;
> Priyanka Jain <priyanka.jain@nxp.com>; Ye Li <ye.li@nxp.com>; Horia Geanta
> <horia.geanta@nxp.com>; Silvano Di Ninno <silvano.dininno@nxp.com>; Varun
> Sethi <V.Sethi@nxp.com>; dl-uboot-imx <uboot-imx@nxp.com>; Gaurav Jain
> <gaurav.jain@nxp.com>
> 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 <gaurav.jain@nxp.com>
> ---
>  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
> 1d951cf0a6..85a3dac796 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 7b6e3e2c20..d57c4ca820 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 */
> --
> 2.25.1

[PATCH] i.MX6SX: crypto/fsl: fix entropy delay value

[sbabic]

> 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 <gaurav.jain@nxp.com>
> Reviewed-by: Fabio Estevam <festevam@denx.de>
Applied to u-boot-imx, master, thanks !

Best regards,
Stefano Babic

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