[PATCH 08/13] nvmem: add kvx otp non volatile regbank support

[Sascha Hauer]

On Fri, Jan 14, 2022 at 05:52:07PM +0100, Jules Maselbas wrote:
> From: Clement Leger <cleger at kalray.eu>
> 
> Backport Linux driver to barebox to access nvmem.
> 
> Signed-off-by: Clement Leger <cleger at kalray.eu>
> Signed-off-by: Jules Maselbas <jmaselbas at kalray.eu>
> ---
>  drivers/nvmem/Kconfig      |  7 +++
>  drivers/nvmem/Makefile     |  3 ++
>  drivers/nvmem/kvx-otp-nv.c | 99 ++++++++++++++++++++++++++++++++++++++
>  3 files changed, 109 insertions(+)
>  create mode 100644 drivers/nvmem/kvx-otp-nv.c
> 
> diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
> index 07320101b8..3624cc64b6 100644
> --- a/drivers/nvmem/Kconfig
> +++ b/drivers/nvmem/Kconfig
> @@ -66,6 +66,13 @@ config STM32_BSEC
>  	  This adds support for the STM32 OTP controller. Reads and writes
>  	  to will go to the shadow RAM, not the OTP fuses themselvers.
>  
> +config KVX_OTP_NV
> +	tristate "kalray KVX OTP Non volatile regs Support"
> +	depends on KVX
> +	help
> +	  This is a simple driver to dump specified values of KVX OTP non
> +	  volatile regs.
> +
>  config STARFIVE_OTP
>  	tristate "Starfive OTP Supprot"
>  	depends on SOC_STARFIVE
> diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
> index cd970aaea1..81629ddb27 100644
> --- a/drivers/nvmem/Makefile
> +++ b/drivers/nvmem/Makefile
> @@ -24,4 +24,7 @@ nvmem_eeprom_93xx46-y		:= eeprom_93xx46.o
>  obj-$(CONFIG_STM32_BSEC)	+= nvmem_bsec.o
>  nvmem_bsec-y			:= bsec.o
>  
> +obj-$(CONFIG_KVX_OTP_NV)	+= nvmem-kvx-otp-nv.o
> +nvmem-kvx-otp-nv-y		:= kvx-otp-nv.o
> +
>  obj-$(CONFIG_STARFIVE_OTP)	+= starfive-otp.o
> diff --git a/drivers/nvmem/kvx-otp-nv.c b/drivers/nvmem/kvx-otp-nv.c
> new file mode 100644
> index 0000000000..f997f8a63b
> --- /dev/null
> +++ b/drivers/nvmem/kvx-otp-nv.c
> @@ -0,0 +1,99 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) 2020 Kalray Inc., Clément Léger
> + */
> +
> +#include <common.h>
> +#include <driver.h>
> +#include <malloc.h>
> +#include <xfuncs.h>
> +#include <errno.h>
> +#include <init.h>
> +#include <net.h>
> +#include <io.h>
> +
> +#include <linux/nvmem-provider.h>
> +
> +#define OTP_NV_ALIGN		4
> +#define OTP_NV_ALIGN_MASK	(OTP_NV_ALIGN - 1)
> +
> +struct kvx_otp_nv_priv {
> +	void __iomem *base;
> +};
> +
> +static int kvx_otp_nv_read(void *context, unsigned int offset,
> +			  void *_val, size_t bytes)
> +{
> +	struct kvx_otp_nv_priv *priv = context;
> +	u8 *val = _val;
> +	u32 tmp, copy_size;
> +	u8 skip = offset & OTP_NV_ALIGN_MASK;
> +
> +	offset &= ~OTP_NV_ALIGN_MASK;
> +
> +	while (bytes) {
> +		tmp = readl(priv->base + offset);
> +		if (skip != 0)
> +			copy_size = min(OTP_NV_ALIGN - skip, (int) bytes);
> +		else
> +			copy_size = min(bytes, sizeof(tmp));
> +
> +		memcpy(val, ((u8 *) &tmp) + skip, copy_size);
> +		if (skip != 0)
> +			skip = 0;

The if() here is unnecessary.

Sascha

-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |