Add driver for efuse found on Rockchip RK3066,RK3188,RK3288 and RK3368 SoCs. eFuse is organized as 32bits by 8 one-time programmable electrical fuses with random access interface. Signed-off-by: Jianqun Xu <jay.xu@xxxxxxxxxxxxxx> Signed-off-by: Caesar Wang <wxt@xxxxxxxxxxxxxx> --- Changes in v2: - Move the efuse driver into driver/soc/vendor. - update the efuse driver. drivers/soc/Makefile | 1 + drivers/soc/rockchip/Makefile | 4 + drivers/soc/rockchip/efuse.c | 212 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 217 insertions(+) create mode 100644 drivers/soc/rockchip/Makefile create mode 100644 drivers/soc/rockchip/efuse.c diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile index 70042b2..91f7f18 100644 --- a/drivers/soc/Makefile +++ b/drivers/soc/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_ARCH_MEDIATEK) += mediatek/ obj-$(CONFIG_ARCH_QCOM) += qcom/ +obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/ obj-$(CONFIG_ARCH_TEGRA) += tegra/ obj-$(CONFIG_SOC_TI) += ti/ obj-$(CONFIG_PLAT_VERSATILE) += versatile/ diff --git a/drivers/soc/rockchip/Makefile b/drivers/soc/rockchip/Makefile new file mode 100644 index 0000000..4f5f9bd --- /dev/null +++ b/drivers/soc/rockchip/Makefile @@ -0,0 +1,4 @@ +# +# Rockchip Soc drivers +# +obj-$(CONFIG_ARCH_ROCKCHIP) += efuse.o diff --git a/drivers/soc/rockchip/efuse.c b/drivers/soc/rockchip/efuse.c new file mode 100644 index 0000000..1125320 --- /dev/null +++ b/drivers/soc/rockchip/efuse.c @@ -0,0 +1,212 @@ +/* + * Rockchip eFuse Driver + * + * Copyright (c) 2015 Rockchip Electronics Co. Ltd. + * Author: Jianqun Xu <jay.xu@xxxxxxxxxxxxxx> + * Author: Caesar Wang <wxt@xxxxxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of version 2 of the GNU General Public License 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/io.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> + +#define EFUSE_A_SHIFT 6 +#define EFUSE_A_MASK 0x3ff +#define EFUSE_PGENB BIT(3) +#define EFUSE_LOAD BIT(2) +#define EFUSE_STROBE BIT(1) +#define EFUSE_CSB BIT(0) + +#define REG_EFUSE_CTRL 0x0000 +#define REG_EFUSE_DOUT 0x0004 + +#define EFUSE_BUF_SIZE 32 +#define EFUSE_CHIP_VERSION_OFFSET 6 +#define EFUSE_CHIP_VERSION_MASK 0xf +#define EFUSE_BUF_LKG_CPU 23 + +struct rockchip_efuse_info { + struct device *dev; + void __iomem *regs; + u32 buf[EFUSE_BUF_SIZE]; +}; + +static void efuse_writel(struct rockchip_efuse_info *efuse, + unsigned int value, + unsigned int offset) +{ + writel_relaxed(value, efuse->regs + offset); +} + +static unsigned int efuse_readl(struct rockchip_efuse_info *efuse, + unsigned int offset) +{ + return readl_relaxed(efuse->regs + offset); +} + +int rockchip_efuse_get_cpuleakage(struct platform_device *pdev, + unsigned int *value) +{ + struct rockchip_efuse_info *efuse; + + efuse = platform_get_drvdata(pdev); + if (!efuse) + return -EAGAIN; + + *value = efuse->buf[EFUSE_BUF_LKG_CPU]; + + return 0; +} +EXPORT_SYMBOL_GPL(rockchip_efuse_get_cpuleakage); + +int rockchip_efuse_get_chip_version(struct platform_device *pdev, + unsigned int *value) +{ + struct rockchip_efuse_info *efuse; + + efuse = platform_get_drvdata(pdev); + if (!efuse) + return -EAGAIN; + + *value = efuse->buf[EFUSE_CHIP_VERSION_OFFSET] & + EFUSE_CHIP_VERSION_MASK; + + return 0; +} +EXPORT_SYMBOL_GPL(rockchip_efuse_get_chip_version); + +static ssize_t cpu_leakage_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int leakage; + int ret; + struct platform_device *pdev = to_platform_device(dev); + + ret = rockchip_efuse_get_cpuleakage(pdev, &leakage); + if (ret) + return ret; + + return sprintf(buf, "%d\n", leakage); +} + +static ssize_t cpu_version_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int version; + int ret; + struct platform_device *pdev = to_platform_device(dev); + + ret = rockchip_efuse_get_chip_version(pdev, &version); + if (ret) + return ret; + + return sprintf(buf, "%d\n", version); +} + +static void rockchip_efuse_init(struct rockchip_efuse_info *efuse) +{ + unsigned int start; + + efuse_writel(efuse, EFUSE_LOAD | EFUSE_PGENB, REG_EFUSE_CTRL); + udelay(1); + + for (start = 0; start <= EFUSE_BUF_SIZE; start++) { + efuse_writel(efuse, efuse_readl(efuse, REG_EFUSE_CTRL) & + (~(EFUSE_A_MASK << EFUSE_A_SHIFT)), + REG_EFUSE_CTRL); + efuse_writel(efuse, efuse_readl(efuse, REG_EFUSE_CTRL) | + ((start & EFUSE_A_MASK) << EFUSE_A_SHIFT), + REG_EFUSE_CTRL); + udelay(1); + efuse_writel(efuse, efuse_readl(efuse, REG_EFUSE_CTRL) | + EFUSE_STROBE, REG_EFUSE_CTRL); + udelay(1); + + efuse->buf[start] = efuse_readl(efuse, REG_EFUSE_DOUT); + + efuse_writel(efuse, efuse_readl(efuse, REG_EFUSE_CTRL) & + (~EFUSE_STROBE), REG_EFUSE_CTRL); + udelay(1); + } + + /* Switch to standby mode */ + efuse_writel(efuse, EFUSE_PGENB | EFUSE_CSB, REG_EFUSE_CTRL); +} + +static DEVICE_ATTR(cpu_leakage_show, 0444, cpu_leakage_show, NULL); +static DEVICE_ATTR(cpu_version_show, 0444, cpu_version_show, NULL); + +static struct attribute *efuse_attributes[] = { + &dev_attr_cpu_leakage_show.attr, + &dev_attr_cpu_version_show.attr, + NULL, +}; + +static const struct attribute_group efuse_attr_group = { + .attrs = efuse_attributes, +}; + +static int rockchip_efuse_probe(struct platform_device *pdev) +{ + struct rockchip_efuse_info *efuse; + struct resource *mem; + int ret; + + efuse = devm_kzalloc(&pdev->dev, sizeof(struct rockchip_efuse_info), + GFP_KERNEL); + if (!efuse) + return -ENOMEM; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + efuse->regs = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(efuse->regs)) + return PTR_ERR(efuse->regs); + + efuse->dev = &pdev->dev; + + rockchip_efuse_init(efuse); + + /* + * We set driver data only after fully initializing efuse + * to make sure rockchip_efuse_get_cpuleakage() and + * rockchip_efuse_get_cpu_version do not return garbage. + */ + platform_set_drvdata(pdev, efuse); + + ret = sysfs_create_group(&efuse->dev->kobj, &efuse_attr_group); + if (ret) { + dev_err(efuse->dev, + "failed to register sysfs. err: %d\n", ret); + return ret; + } + + return 0; +} + +static const struct of_device_id rockchip_efuse_match[] = { + { .compatible = "rockchip,rk3066-efuse", }, + { /* sentinel */}, +}; + +static struct platform_driver rockchip_efuse_driver = { + .probe = rockchip_efuse_probe, + .driver = { + .name = "rockchip-efuse", + .of_match_table = of_match_ptr(rockchip_efuse_match), + .suppress_bind_attrs = true, + }, +}; + +module_platform_driver(rockchip_efuse_driver); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html