linux-kernel - Re: [PATCH 2/2] hwrng: iproc-rng200: Move enable/disable in separate function

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Message-ID: <9f87ad0f-b281-33f4-b81d-e62a37d536fc@broadcom.com>
Date:   Mon, 14 Dec 2020 09:50:24 -0800
From:   Scott Branden <scott.branden@...adcom.com>
To:     matthias.bgg@...nel.org, mpm@...enic.com,
        herbert@...dor.apana.org.au, rjui@...adcom.com,
        sbranden@...adcom.com, f.fainelli@...il.com
Cc:     linux-kernel@...r.kernel.org, Julia.Lawall@...ia.fr,
        bcm-kernel-feedback-list@...adcom.com,
        linux-arm-kernel@...ts.infradead.org, nsaenzjulienne@...e.de,
        linux-crypto@...r.kernel.org, Matthias Brugger <mbrugger@...e.com>
Subject: Re: [PATCH 2/2] hwrng: iproc-rng200: Move enable/disable in separate
 function



On 2020-12-14 8:04 a.m., matthias.bgg@...nel.org wrote:
> From: Matthias Brugger <mbrugger@...e.com>
>
> We are calling the same code for enable and disable the block in various
> parts of the driver. Put that code into a new function to reduce code
> duplication.
Patch needs to be regenerated after most of PATCH 1 dropped.
>
> Signed-off-by: Matthias Brugger <mbrugger@...e.com>
>
> ---
>
>  drivers/char/hw_random/iproc-rng200.c | 37 ++++++++++++---------------
>  1 file changed, 17 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/char/hw_random/iproc-rng200.c b/drivers/char/hw_random/iproc-rng200.c
> index e106ce3c0146..3367b26085e8 100644
> --- a/drivers/char/hw_random/iproc-rng200.c
> +++ b/drivers/char/hw_random/iproc-rng200.c
> @@ -53,15 +53,26 @@ struct iproc_rng200_dev {
>  
>  #define to_rng_priv(rng)	container_of(rng, struct iproc_rng200_dev, rng)
>  
> -static void iproc_rng200_restart(void __iomem *rng_base)
> +static void iproc_rng200_enable(void __iomem *rng_base, bool enable)
>  {
>  	uint32_t val;
>  
> -	/* Disable RBG */
>  	val = ioread32(rng_base + RNG_CTRL_OFFSET);
>  	val &= ~RNG_CTRL_RNG_RBGEN_MASK;
> -	val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
> +
> +	if (enable)
> +		val |= RNG_CTRL_RNG_RBGEN_ENABLE;
> +	else
> +		val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
> +
>  	iowrite32(val, rng_base + RNG_CTRL_OFFSET);
> +}
> +
> +static void iproc_rng200_restart(void __iomem *rng_base)
> +{
> +	uint32_t val;
> +
> +	iproc_rng200_enable(rng_base, false);
>  
>  	/* Clear all interrupt status */
>  	iowrite32(0xFFFFFFFFUL, rng_base + RNG_INT_STATUS_OFFSET);
> @@ -83,11 +94,7 @@ static void iproc_rng200_restart(void __iomem *rng_base)
>  	val &= ~RBG_SOFT_RESET;
>  	iowrite32(val, rng_base + RBG_SOFT_RESET_OFFSET);
>  
> -	/* Enable RBG */
> -	val = ioread32(rng_base + RNG_CTRL_OFFSET);
> -	val &= ~RNG_CTRL_RNG_RBGEN_MASK;
> -	val |= RNG_CTRL_RNG_RBGEN_ENABLE;
> -	iowrite32(val, rng_base + RNG_CTRL_OFFSET);
> +	iproc_rng200_enable(rng_base, true);
>  }
>  
>  static int iproc_rng200_read(struct hwrng *rng, void *buf, size_t max,
> @@ -154,13 +161,8 @@ static int iproc_rng200_read(struct hwrng *rng, void *buf, size_t max,
>  static int iproc_rng200_init(struct hwrng *rng)
>  {
>  	struct iproc_rng200_dev *priv = to_rng_priv(rng);
> -	uint32_t val;
>  
> -	/* Setup RNG. */
> -	val = ioread32(priv->base + RNG_CTRL_OFFSET);
> -	val &= ~RNG_CTRL_RNG_RBGEN_MASK;
> -	val |= RNG_CTRL_RNG_RBGEN_ENABLE;
> -	iowrite32(val, priv->base + RNG_CTRL_OFFSET);
> +	iproc_rng200_enable(priv->base, true);
>  
>  	return 0;
>  }
> @@ -168,13 +170,8 @@ static int iproc_rng200_init(struct hwrng *rng)
>  static void iproc_rng200_cleanup(struct hwrng *rng)
>  {
>  	struct iproc_rng200_dev *priv = to_rng_priv(rng);
> -	uint32_t val;
>  
> -	/* Disable RNG hardware */
> -	val = ioread32(priv->base + RNG_CTRL_OFFSET);
> -	val &= ~RNG_CTRL_RNG_RBGEN_MASK;
> -	val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;
> -	iowrite32(val, priv->base + RNG_CTRL_OFFSET);
> +	iproc_rng200_enable(priv->base, false);
>  }
>  
>  static int iproc_rng200_probe(struct platform_device *pdev)