From: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
To: Martin Kaiser <martin@kaiser.cx>
Cc: Herbert Xu <herbert@gondor.apana.org.au>,
NXP Linux Team <linux-imx@nxp.com>,
"open list:HARDWARE RANDOM NUMBER GENERATOR CORE"
<linux-crypto@vger.kernel.org>,
linux-arm-kernel@lists.infradead.org,
open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 5/6] hwrng: imx-rngc - check the rng type
Date: Wed, 12 Feb 2020 21:53:09 +0530 [thread overview]
Message-ID: <CANc+2y6oasMLCzDJAebFca4yoWWTL4r3Esyws-K5EuMLwbuAqA@mail.gmail.com> (raw)
In-Reply-To: <20200128110102.11522-6-martin@kaiser.cx>
On Tue, 28 Jan 2020 at 16:31, Martin Kaiser <martin@kaiser.cx> wrote:
>
> Read the rng type and hardware revision during probe. Fail the probe
> operation if the type is not one of rngc or rngb.
> (There's also an rnga type, which needs a different driver.)
>
> Display the type and revision in a debug print if probe was successful.
>
> Signed-off-by: Martin Kaiser <martin@kaiser.cx>
> ---
> drivers/char/hw_random/imx-rngc.c | 28 +++++++++++++++++++++++++++-
> 1 file changed, 27 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
> index 8222055b9e9b..27d85fced30b 100644
> --- a/drivers/char/hw_random/imx-rngc.c
> +++ b/drivers/char/hw_random/imx-rngc.c
> @@ -18,12 +18,22 @@
> #include <linux/completion.h>
> #include <linux/io.h>
>
> +#define RNGC_VER_ID 0x0000
> #define RNGC_COMMAND 0x0004
> #define RNGC_CONTROL 0x0008
> #define RNGC_STATUS 0x000C
> #define RNGC_ERROR 0x0010
> #define RNGC_FIFO 0x0014
>
> +/* the fields in the ver id register */
> +#define RNGC_TYPE_SHIFT 28
> +#define RNGC_VER_MAJ_SHIFT 8
> +
> +/* the rng_type field */
> +#define RNGC_TYPE_RNGB 0x1
> +#define RNGC_TYPE_RNGC 0x2
> +
> +
> #define RNGC_CMD_CLR_ERR 0x00000020
> #define RNGC_CMD_CLR_INT 0x00000010
> #define RNGC_CMD_SEED 0x00000002
> @@ -212,6 +222,8 @@ static int imx_rngc_probe(struct platform_device *pdev)
> struct imx_rngc *rngc;
> int ret;
> int irq;
> + u32 ver_id;
> + u8 rng_type;
>
> rngc = devm_kzalloc(&pdev->dev, sizeof(*rngc), GFP_KERNEL);
> if (!rngc)
> @@ -237,6 +249,17 @@ static int imx_rngc_probe(struct platform_device *pdev)
> if (ret)
> return ret;
>
> + ver_id = readl(rngc->base + RNGC_VER_ID);
> + rng_type = ver_id >> RNGC_TYPE_SHIFT;
> + /*
> + * This driver supports only RNGC and RNGB. (There's a different
> + * driver for RNGA.)
> + */
> + if (rng_type != RNGC_TYPE_RNGC && rng_type != RNGC_TYPE_RNGB) {
> + ret = -ENODEV;
> + goto err;
> + }
> +
> ret = devm_request_irq(&pdev->dev,
> irq, imx_rngc_irq, 0, pdev->name, (void *)rngc);
> if (ret) {
> @@ -269,7 +292,10 @@ static int imx_rngc_probe(struct platform_device *pdev)
> goto err;
> }
>
> - dev_info(&pdev->dev, "Freescale RNGC registered.\n");
> + dev_info(&pdev->dev,
> + "Freescale RNG%c registered (HW revision %d.%02d)\n",
> + rng_type == RNGC_TYPE_RNGB ? 'B' : 'C',
> + (ver_id >> RNGC_VER_MAJ_SHIFT) & 0xff, ver_id & 0xff);
> return 0;
>
> err:
> --
> 2.20.1
>
Reviewed-by: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
next prev parent reply other threads:[~2020-02-12 16:23 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-28 11:00 [PATCH 0/6] imx-rngc - several small fixes Martin Kaiser
2020-01-28 11:00 ` [PATCH 1/6] hwrng: imx-rngc - fix an error path Martin Kaiser
2020-02-12 16:22 ` PrasannaKumar Muralidharan
2020-01-28 11:00 ` [PATCH 2/6] hwrng: imx-rngc - use automatic seeding Martin Kaiser
2020-02-12 16:24 ` PrasannaKumar Muralidharan
2020-01-28 11:00 ` [PATCH 3/6] hwrng: imx-rngc - use devres for registration Martin Kaiser
2020-02-12 16:13 ` PrasannaKumar Muralidharan
2020-02-17 9:35 ` Martin Kaiser
2020-01-28 11:01 ` [PATCH 4/6] hwrng: imx-rngc - (trivial) simplify error prints Martin Kaiser
2020-02-12 16:24 ` PrasannaKumar Muralidharan
2020-01-28 11:01 ` [PATCH 5/6] hwrng: imx-rngc - check the rng type Martin Kaiser
2020-02-12 16:23 ` PrasannaKumar Muralidharan [this message]
2020-01-28 11:01 ` [PATCH 6/6] hwrng: imx-rngc - simplify interrupt mask/unmask Martin Kaiser
2020-03-05 20:58 ` [PATCH v2 0/5] imx-rngc - several small fixes Martin Kaiser
2020-03-05 20:58 ` [PATCH v2 1/5] hwrng: imx-rngc - fix an error path Martin Kaiser
2020-03-05 20:58 ` [PATCH v2 2/5] hwrng: imx-rngc - use automatic seeding Martin Kaiser
2020-03-05 20:58 ` [PATCH v2 3/5] hwrng: imx-rngc - (trivial) simplify error prints Martin Kaiser
2020-03-05 20:58 ` [PATCH v2 4/5] hwrng: imx-rngc - check the rng type Martin Kaiser
2020-03-05 20:58 ` [PATCH v2 5/5] hwrng: imx-rngc - simplify interrupt mask/unmask Martin Kaiser
2020-03-12 12:39 ` [PATCH v2 0/5] imx-rngc - several small fixes Herbert Xu
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