[PATCH v8 3/4] drivers: nvmem: Add Vybrid OCOTP support
Srinivas Kandagatla
srinivas.kandagatla at linaro.org
Mon Aug 10 07:56:54 PDT 2015
Hi Sanchayan,
On 10/08/15 15:11, Sanchayan Maity wrote:
> The patch adds support for the On Chip One Time Programmable Peripheral
> (OCOTP) on the Vybrid platform.
>
> Signed-off-by: Sanchayan Maity <maitysanchayan at gmail.com>
> ---
> drivers/nvmem/Kconfig | 10 ++
> drivers/nvmem/Makefile | 2 +
> drivers/nvmem/vf610-ocotp.c | 301 ++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 313 insertions(+)
> create mode 100644 drivers/nvmem/vf610-ocotp.c
>
Patch looks good to me,
Acked-by: Srinivas Kandagatla <srinivas.kandagatla at linaro.org>
--srini
> diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
> index 0b33014..7af4c1d 100644
> --- a/drivers/nvmem/Kconfig
> +++ b/drivers/nvmem/Kconfig
> @@ -47,4 +47,14 @@ 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_VF610_OCOTP
> + tristate "VF610_SoCs OCOTP support"
> + depends on SOC_VF610 || COMPILE_TEST
> + help
> + This is a driver for the 'OCOTP' peripheral available on Vybrid
> + devices like VF5xx and VF6xx.
> +
> + This driver can also be built as a module. If so, the module will
> + be called nvmem-vf610-ocotp.
> +
> endif
> diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
> index b512d77..8a1eea8 100644
> --- a/drivers/nvmem/Makefile
> +++ b/drivers/nvmem/Makefile
> @@ -12,3 +12,5 @@ obj-$(CONFIG_NVMEM_SUNXI_SID) += nvmem_sunxi_sid.o
> nvmem_sunxi_sid-y := sunxi_sid.o
> obj-$(CONFIG_NVMEM_IMX_OCOTP) += nvmem-imx-ocotp.o
> nvmem-imx-ocotp-y := imx-ocotp.o
> +obj-$(CONFIG_NVMEM_VF610_OCOTP) += nvmem-vf610-ocotp.o
> +nvmem-vf610-ocotp-y := vf610-ocotp.o
> diff --git a/drivers/nvmem/vf610-ocotp.c b/drivers/nvmem/vf610-ocotp.c
> new file mode 100644
> index 0000000..9e18156
> --- /dev/null
> +++ b/drivers/nvmem/vf610-ocotp.c
> @@ -0,0 +1,301 @@
> +/*
> + * Copyright (C) 2015 Toradex AG.
> + *
> + * Author: Sanchayan Maity <sanchayan.maity at toradex.com>
> + *
> + * Based on the barebox ocotp driver,
> + * Copyright (c) 2010 Baruch Siach <baruch at tkos.co.il>
> + * Orex Computed Radiography
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-provider.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +
> +/* OCOTP Register Offsets */
> +#define OCOTP_CTRL_REG 0x00
> +#define OCOTP_CTRL_SET 0x04
> +#define OCOTP_CTRL_CLR 0x08
> +#define OCOTP_TIMING 0x10
> +#define OCOTP_DATA 0x20
> +#define OCOTP_READ_CTRL_REG 0x30
> +#define OCOTP_READ_FUSE_DATA 0x40
> +
> +/* OCOTP Register bits and masks */
> +#define OCOTP_CTRL_WR_UNLOCK 16
> +#define OCOTP_CTRL_WR_UNLOCK_KEY 0x3E77
> +#define OCOTP_CTRL_WR_UNLOCK_MASK GENMASK(31, 16)
> +#define OCOTP_CTRL_ADDR 0
> +#define OCOTP_CTRL_ADDR_MASK GENMASK(6, 0)
> +#define OCOTP_CTRL_RELOAD_SHADOWS BIT(10)
> +#define OCOTP_CTRL_ERROR BIT(9)
> +#define OCOTP_CTRL_BUSY BIT(8)
> +
> +#define OCOTP_TIMING_STROBE_READ 16
> +#define OCOTP_TIMING_STROBE_READ_MASK GENMASK(21, 16)
> +#define OCOTP_TIMING_RELAX 12
> +#define OCOTP_TIMING_RELAX_MASK GENMASK(15, 12)
> +#define OCOTP_TIMING_STROBE_PROG 0
> +#define OCOTP_TIMING_STROBE_PROG_MASK GENMASK(11, 0)
> +
> +#define OCOTP_READ_CTRL_READ_FUSE 0x1
> +
> +#define VF610_OCOTP_TIMEOUT 100000
> +
> +#define BF(value, field) (((value) << field) & field##_MASK)
> +
> +#define DEF_RELAX 20
> +
> +static const int base_to_fuse_addr_mappings[][2] = {
> + {0x400, 0x00},
> + {0x410, 0x01},
> + {0x420, 0x02},
> + {0x450, 0x05},
> + {0x4F0, 0x0F},
> + {0x600, 0x20},
> + {0x610, 0x21},
> + {0x620, 0x22},
> + {0x630, 0x23},
> + {0x640, 0x24},
> + {0x650, 0x25},
> + {0x660, 0x26},
> + {0x670, 0x27},
> + {0x6F0, 0x2F},
> + {0x880, 0x38},
> + {0x890, 0x39},
> + {0x8A0, 0x3A},
> + {0x8B0, 0x3B},
> + {0x8C0, 0x3C},
> + {0x8D0, 0x3D},
> + {0x8E0, 0x3E},
> + {0x8F0, 0x3F},
> + {0xC80, 0x78},
> + {0xC90, 0x79},
> + {0xCA0, 0x7A},
> + {0xCB0, 0x7B},
> + {0xCC0, 0x7C},
> + {0xCD0, 0x7D},
> + {0xCE0, 0x7E},
> + {0xCF0, 0x7F},
> +};
> +
> +struct vf610_ocotp {
> + void __iomem *base;
> + struct clk *clk;
> + struct device *dev;
> + struct nvmem_device *nvmem;
> + int timing;
> +};
> +
> +static int vf610_ocotp_wait_busy(void __iomem *base)
> +{
> + int timeout = VF610_OCOTP_TIMEOUT;
> +
> + while ((readl(base) & OCOTP_CTRL_BUSY) && --timeout)
> + udelay(10);
> +
> + if (!timeout) {
> + writel(OCOTP_CTRL_ERROR, base + OCOTP_CTRL_CLR);
> + return -ETIMEDOUT;
> + }
> +
> + udelay(10);
> +
> + return 0;
> +}
> +
> +static int vf610_ocotp_calculate_timing(struct vf610_ocotp *ocotp_dev)
> +{
> + u32 clk_rate;
> + u32 relax, strobe_read, strobe_prog;
> + u32 timing;
> +
> + clk_rate = clk_get_rate(ocotp_dev->clk);
> +
> + /* Refer section OTP read/write timing parameters in TRM */
> + relax = clk_rate / (1000000000 / DEF_RELAX) - 1;
> + strobe_prog = clk_rate / (1000000000 / 10000) + 2 * (DEF_RELAX + 1) - 1;
> + strobe_read = clk_rate / (1000000000 / 40) + 2 * (DEF_RELAX + 1) - 1;
> +
> + timing = BF(relax, OCOTP_TIMING_RELAX);
> + timing |= BF(strobe_read, OCOTP_TIMING_STROBE_READ);
> + timing |= BF(strobe_prog, OCOTP_TIMING_STROBE_PROG);
> +
> + return timing;
> +}
> +
> +static int vf610_get_fuse_address(int base_addr_offset)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(base_to_fuse_addr_mappings); i++) {
> + if (base_to_fuse_addr_mappings[i][0] == base_addr_offset)
> + return base_to_fuse_addr_mappings[i][1];
> + }
> +
> + return -EINVAL;
> +}
> +
> +static int vf610_ocotp_write(void *context, const void *data, size_t count)
> +{
> + return 0;
> +}
> +
> +static int vf610_ocotp_read(void *context,
> + const void *off, size_t reg_size,
> + void *val, size_t val_size)
> +{
> + struct vf610_ocotp *ocotp = context;
> + unsigned int offset = *(u32 *)off;
> + u32 reg, *buf = val;
> + int fuse_addr;
> + int ret;
> +
> + while (val_size > 0) {
> + fuse_addr = vf610_get_fuse_address(offset);
> + if (fuse_addr > 0) {
> + writel(ocotp->timing, ocotp->base + OCOTP_TIMING);
> + ret = vf610_ocotp_wait_busy(ocotp->base + OCOTP_CTRL_REG);
> + if (ret)
> + return ret;
> +
> + reg = readl(ocotp->base + OCOTP_CTRL_REG);
> + reg &= ~OCOTP_CTRL_ADDR_MASK;
> + reg &= ~OCOTP_CTRL_WR_UNLOCK_MASK;
> + reg |= BF(fuse_addr, OCOTP_CTRL_ADDR);
> + writel(reg, ocotp->base + OCOTP_CTRL_REG);
> +
> + writel(OCOTP_READ_CTRL_READ_FUSE,
> + ocotp->base + OCOTP_READ_CTRL_REG);
> + ret = vf610_ocotp_wait_busy(ocotp->base + OCOTP_CTRL_REG);
> + if (ret)
> + return ret;
> +
> + if (readl(ocotp->base) & OCOTP_CTRL_ERROR) {
> + dev_dbg(ocotp->dev, "Error reading from fuse address %x\n",
> + fuse_addr);
> + writel(OCOTP_CTRL_ERROR, ocotp->base + OCOTP_CTRL_CLR);
> + }
> +
> + /*
> + * In case of error, we do not abort and expect to read
> + * 0xBADABADA as mentioned by the TRM. We just read this
> + * value and return.
> + */
> + *buf = readl(ocotp->base + OCOTP_READ_FUSE_DATA);
> + } else {
> + *buf = 0;
> + }
> +
> + buf++;
> + val_size--;
> + offset += reg_size;
> + }
> +
> + return 0;
> +}
> +
> +static struct regmap_bus vf610_ocotp_bus = {
> + .read = vf610_ocotp_read,
> + .write = vf610_ocotp_write,
> + .reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
> + .val_format_endian_default = REGMAP_ENDIAN_NATIVE,
> +};
> +
> +static struct regmap_config ocotp_regmap_config = {
> + .reg_bits = 32,
> + .val_bits = 32,
> + .reg_stride = 4,
> +};
> +
> +static struct nvmem_config ocotp_config = {
> + .name = "ocotp",
> + .owner = THIS_MODULE,
> +};
> +
> +static const struct of_device_id ocotp_of_match[] = {
> + { .compatible = "fsl,vf610-ocotp", },
> + {/* sentinel */},
> +};
> +MODULE_DEVICE_TABLE(of, ocotp_of_match);
> +
> +static int vf610_ocotp_remove(struct platform_device *pdev)
> +{
> + struct vf610_ocotp *ocotp_dev = platform_get_drvdata(pdev);
> +
> + return nvmem_unregister(ocotp_dev->nvmem);
> +}
> +
> +static int vf610_ocotp_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct resource *res;
> + struct regmap *regmap;
> + struct vf610_ocotp *ocotp_dev;
> +
> + ocotp_dev = devm_kzalloc(&pdev->dev,
> + sizeof(struct vf610_ocotp), GFP_KERNEL);
> + if (!ocotp_dev)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + ocotp_dev->base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(ocotp_dev->base))
> + return PTR_ERR(ocotp_dev->base);
> +
> + ocotp_dev->clk = devm_clk_get(dev, "ocotp");
> + if (IS_ERR(ocotp_dev->clk)) {
> + dev_err(dev, "failed getting clock, err = %ld\n",
> + PTR_ERR(ocotp_dev->clk));
> + return PTR_ERR(ocotp_dev->clk);
> + }
> +
> + ocotp_regmap_config.max_register = resource_size(res);
> + regmap = devm_regmap_init(dev,
> + &vf610_ocotp_bus, ocotp_dev, &ocotp_regmap_config);
> + if (IS_ERR(regmap)) {
> + dev_err(dev, "regmap init failed\n");
> + return PTR_ERR(regmap);
> + }
> + ocotp_config.dev = dev;
> +
> + ocotp_dev->nvmem = nvmem_register(&ocotp_config);
> + if (IS_ERR(ocotp_dev->nvmem))
> + return PTR_ERR(ocotp_dev->nvmem);
> +
> + ocotp_dev->dev = dev;
> + platform_set_drvdata(pdev, ocotp_dev);
> +
> + ocotp_dev->timing = vf610_ocotp_calculate_timing(ocotp_dev);
> +
> + return 0;
> +}
> +
> +static struct platform_driver vf610_ocotp_driver = {
> + .probe = vf610_ocotp_probe,
> + .remove = vf610_ocotp_remove,
> + .driver = {
> + .name = "vf610-ocotp",
> + .of_match_table = ocotp_of_match,
> + },
> +};
> +module_platform_driver(vf610_ocotp_driver);
> +MODULE_AUTHOR("Sanchayan Maity <sanchayan.maity at toradex.com>");
> +MODULE_DESCRIPTION("Vybrid OCOTP driver");
> +MODULE_LICENSE("GPL v2");
>
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