RE: [PATCH V2 2/2] nvmem: imx: support i.MX93 OCOTP

[Peng Fan]

Hi Srinivas

> Subject: [PATCH V2 2/2] nvmem: imx: support i.MX93 OCOTP

The patch v2 1/2 has got R-b from DT maintainers. Are you fine with 
Patch v2 2/2?

Thanks,
Peng.
> 
> From: Peng Fan <peng.fan@xxxxxxx>
> 
> Add i.MX93 OCOTP support. i.MX93 OCOTP has two parts: Fuse shadow
> block(fsb) and fuse managed by ELE. The FSB part could be directly accessed
> with MMIO, the ELE could only be accessed with ELE API.
> 
> Currently the ELE API is not ready, so NULL function callback is used, but it
> was tested with downstream ELE API.
> 
> Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> ---
> 
> V2:
>  Merge ele & fsb compatible to use fsl,imx93-ocotp
> 
>  drivers/nvmem/Kconfig         |   9 ++
>  drivers/nvmem/Makefile        |   2 +
>  drivers/nvmem/imx-ocotp-ele.c | 175
> ++++++++++++++++++++++++++++++++++
>  3 files changed, 186 insertions(+)
>  create mode 100644 drivers/nvmem/imx-ocotp-ele.c
> 
> diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig index
> b291b27048c7..e7093726b28e 100644
> --- a/drivers/nvmem/Kconfig
> +++ b/drivers/nvmem/Kconfig
> @@ -82,6 +82,15 @@ config NVMEM_IMX_OCOTP
>  	  This driver can also be built as a module. If so, the module
>  	  will be called nvmem-imx-ocotp.
> 
> +config NVMEM_IMX_OCOTP_ELE
> +	tristate "i.MX On-Chip OTP Controller support"
> +	depends on ARCH_MXC || COMPILE_TEST
> +	depends on HAS_IOMEM
> +	depends on OF
> +	help
> +	  This is a driver for the On-Chip OTP Controller (OCOTP)
> +	  available on i.MX SoCs which has ELE.
> +
>  config NVMEM_IMX_OCOTP_SCU
>  	tristate "i.MX8 SCU On-Chip OTP Controller support"
>  	depends on IMX_SCU
> diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile index
> f82431ec8aef..cc23ce4ffb1f 100644
> --- a/drivers/nvmem/Makefile
> +++ b/drivers/nvmem/Makefile
> @@ -18,6 +18,8 @@ obj-$(CONFIG_NVMEM_IMX_IIM)		+=
> nvmem-imx-iim.o
>  nvmem-imx-iim-y				:= imx-iim.o
>  obj-$(CONFIG_NVMEM_IMX_OCOTP)		+= nvmem-imx-ocotp.o
>  nvmem-imx-ocotp-y			:= imx-ocotp.o
> +obj-$(CONFIG_NVMEM_IMX_OCOTP_ELE)	+= nvmem-imx-ocotp-ele.o
> +nvmem-imx-ocotp-ele-y			:= imx-ocotp-ele.o
>  obj-$(CONFIG_NVMEM_IMX_OCOTP_SCU)	+= nvmem-imx-ocotp-scu.o
>  nvmem-imx-ocotp-scu-y			:= imx-ocotp-scu.o
>  obj-$(CONFIG_NVMEM_JZ4780_EFUSE)	+= nvmem_jz4780_efuse.o
> diff --git a/drivers/nvmem/imx-ocotp-ele.c b/drivers/nvmem/imx-ocotp-
> ele.c new file mode 100644 index 000000000000..af9ce0ce4792
> --- /dev/null
> +++ b/drivers/nvmem/imx-ocotp-ele.c
> @@ -0,0 +1,175 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * i.MX9 OCOTP fusebox driver
> + *
> + * Copyright 2023 NXP
> + */
> +
> +#include <linux/device.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-provider.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +enum fuse_type {
> +	FUSE_FSB = 1,
> +	FUSE_ELE = 2,
> +	FUSE_INVALID = -1
> +};
> +
> +struct ocotp_map_entry {
> +	u32 start; /* start word */
> +	u32 num; /* num words */
> +	enum fuse_type type;
> +};
> +
> +struct ocotp_devtype_data {
> +	u32 reg_off;
> +	char *name;
> +	u32 size;
> +	u32 num_entry;
> +	u32 flag;
> +	nvmem_reg_read_t reg_read;
> +	struct ocotp_map_entry entry[];
> +};
> +
> +struct imx_ocotp_priv {
> +	struct device *dev;
> +	void __iomem *base;
> +	struct nvmem_config config;
> +	struct mutex lock;
> +	const struct ocotp_devtype_data *data; };
> +
> +static enum fuse_type imx_ocotp_fuse_type(void *context, u32 index) {
> +	struct imx_ocotp_priv *priv = context;
> +	const struct ocotp_devtype_data *data = priv->data;
> +	u32 start, end;
> +	int i;
> +
> +	for (i = 0; i < data->num_entry; i++) {
> +		start = data->entry[i].start;
> +		end = data->entry[i].start + data->entry[i].num;
> +
> +		if (index >= start && index < end)
> +			return data->entry[i].type;
> +	}
> +
> +	return FUSE_INVALID;
> +}
> +
> +static int imx_ocotp_reg_read(void *context, unsigned int offset, void
> +*val, size_t bytes) {
> +	struct imx_ocotp_priv *priv = context;
> +	void __iomem *reg = priv->base + priv->data->reg_off;
> +	u32 count, index, num_bytes;
> +	enum fuse_type type;
> +	u32 *buf;
> +	void *p;
> +	int i;
> +
> +	index = offset;
> +	num_bytes = round_up(bytes, 4);
> +	count = num_bytes >> 2;
> +
> +	if (count > ((priv->data->size >> 2) - index))
> +		count = (priv->data->size >> 2) - index;
> +
> +	p = kzalloc(num_bytes, GFP_KERNEL);
> +	if (!p)
> +		return -ENOMEM;
> +
> +	mutex_lock(&priv->lock);
> +
> +	buf = p;
> +
> +	for (i = index; i < (index + count); i++) {
> +		type = imx_ocotp_fuse_type(context, i);
> +		if (type == FUSE_INVALID || type == FUSE_ELE) {
> +			*buf++ = 0;
> +			continue;
> +		}
> +
> +		*buf++ = readl_relaxed(reg + (i << 2));
> +	}
> +
> +	memcpy(val, (u8 *)p, bytes);
> +
> +	mutex_unlock(&priv->lock);
> +
> +	kfree(p);
> +
> +	return 0;
> +};
> +
> +static int imx_ele_ocotp_probe(struct platform_device *pdev) {
> +	struct device *dev = &pdev->dev;
> +	struct imx_ocotp_priv *priv;
> +	struct nvmem_device *nvmem;
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->data = of_device_get_match_data(dev);
> +
> +	priv->base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(priv->base))
> +		return PTR_ERR(priv->base);
> +
> +	priv->config.dev = dev;
> +	priv->config.name = "ELE-OCOTP";
> +	priv->config.id = NVMEM_DEVID_AUTO;
> +	priv->config.owner = THIS_MODULE;
> +	priv->config.size = priv->data->size;
> +	priv->config.reg_read = priv->data->reg_read;
> +	priv->config.word_size = 4;
> +	priv->config.stride = 1;
> +	priv->config.priv = priv;
> +	priv->config.read_only = true;
> +	mutex_init(&priv->lock);
> +
> +	nvmem = devm_nvmem_register(dev, &priv->config);
> +	if (IS_ERR(nvmem))
> +		return PTR_ERR(nvmem);
> +
> +	return 0;
> +}
> +
> +static const struct ocotp_devtype_data imx93_ocotp_data = {
> +	.reg_off = 0x8000,
> +	.reg_read = imx_ocotp_reg_read,
> +	.size = 2048,
> +	.num_entry = 6,
> +	.entry = {
> +		{ 0, 52, FUSE_FSB },
> +		{ 63, 1, FUSE_ELE},
> +		{ 128, 16, FUSE_ELE },
> +		{ 182, 1, FUSE_ELE },
> +		{ 188, 1, FUSE_ELE },
> +		{ 312, 200, FUSE_FSB }
> +	},
> +};
> +
> +static const struct of_device_id imx_ele_ocotp_dt_ids[] = {
> +	{ .compatible = "fsl,imx93-ocotp", .data = &imx93_ocotp_data, },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, imx_ele_ocotp_dt_ids);
> +
> +static struct platform_driver imx_ele_ocotp_driver = {
> +	.driver = {
> +		.name = "imx_ele_ocotp",
> +		.of_match_table = imx_ele_ocotp_dt_ids,
> +	},
> +	.probe = imx_ele_ocotp_probe,
> +};
> +module_platform_driver(imx_ele_ocotp_driver);
> +
> +MODULE_DESCRIPTION("i.MX OCOTP/ELE driver");
> MODULE_AUTHOR("Peng Fan
> +<peng.fan@xxxxxxx>"); MODULE_LICENSE("GPL");
> --
> 2.37.1