| // SPDX-License-Identifier: GPL-2.0-only | 
 | /* | 
 |  * Rockchip OTP Driver | 
 |  * | 
 |  * Copyright (c) 2018 Rockchip Electronics Co. Ltd. | 
 |  * Author: Finley Xiao <finley.xiao@rock-chips.com> | 
 |  */ | 
 |  | 
 | #include <linux/clk.h> | 
 | #include <linux/delay.h> | 
 | #include <linux/device.h> | 
 | #include <linux/io.h> | 
 | #include <linux/iopoll.h> | 
 | #include <linux/module.h> | 
 | #include <linux/nvmem-provider.h> | 
 | #include <linux/reset.h> | 
 | #include <linux/slab.h> | 
 | #include <linux/of.h> | 
 | #include <linux/of_platform.h> | 
 | #include <linux/platform_device.h> | 
 |  | 
 | /* OTP Register Offsets */ | 
 | #define OTPC_SBPI_CTRL			0x0020 | 
 | #define OTPC_SBPI_CMD_VALID_PRE		0x0024 | 
 | #define OTPC_SBPI_CS_VALID_PRE		0x0028 | 
 | #define OTPC_SBPI_STATUS		0x002C | 
 | #define OTPC_USER_CTRL			0x0100 | 
 | #define OTPC_USER_ADDR			0x0104 | 
 | #define OTPC_USER_ENABLE		0x0108 | 
 | #define OTPC_USER_Q			0x0124 | 
 | #define OTPC_INT_STATUS			0x0304 | 
 | #define OTPC_SBPI_CMD0_OFFSET		0x1000 | 
 | #define OTPC_SBPI_CMD1_OFFSET		0x1004 | 
 |  | 
 | /* OTP Register bits and masks */ | 
 | #define OTPC_USER_ADDR_MASK		GENMASK(31, 16) | 
 | #define OTPC_USE_USER			BIT(0) | 
 | #define OTPC_USE_USER_MASK		GENMASK(16, 16) | 
 | #define OTPC_USER_FSM_ENABLE		BIT(0) | 
 | #define OTPC_USER_FSM_ENABLE_MASK	GENMASK(16, 16) | 
 | #define OTPC_SBPI_DONE			BIT(1) | 
 | #define OTPC_USER_DONE			BIT(2) | 
 |  | 
 | #define SBPI_DAP_ADDR			0x02 | 
 | #define SBPI_DAP_ADDR_SHIFT		8 | 
 | #define SBPI_DAP_ADDR_MASK		GENMASK(31, 24) | 
 | #define SBPI_CMD_VALID_MASK		GENMASK(31, 16) | 
 | #define SBPI_DAP_CMD_WRF		0xC0 | 
 | #define SBPI_DAP_REG_ECC		0x3A | 
 | #define SBPI_ECC_ENABLE			0x00 | 
 | #define SBPI_ECC_DISABLE		0x09 | 
 | #define SBPI_ENABLE			BIT(0) | 
 | #define SBPI_ENABLE_MASK		GENMASK(16, 16) | 
 |  | 
 | #define OTPC_TIMEOUT			10000 | 
 |  | 
 | /* RK3588 Register */ | 
 | #define RK3588_OTPC_AUTO_CTRL		0x04 | 
 | #define RK3588_OTPC_AUTO_EN		0x08 | 
 | #define RK3588_OTPC_INT_ST		0x84 | 
 | #define RK3588_OTPC_DOUT0		0x20 | 
 | #define RK3588_NO_SECURE_OFFSET		0x300 | 
 | #define RK3588_NBYTES			4 | 
 | #define RK3588_BURST_NUM		1 | 
 | #define RK3588_BURST_SHIFT		8 | 
 | #define RK3588_ADDR_SHIFT		16 | 
 | #define RK3588_AUTO_EN			BIT(0) | 
 | #define RK3588_RD_DONE			BIT(1) | 
 |  | 
 | struct rockchip_data { | 
 | 	int size; | 
 | 	const char * const *clks; | 
 | 	int num_clks; | 
 | 	nvmem_reg_read_t reg_read; | 
 | }; | 
 |  | 
 | struct rockchip_otp { | 
 | 	struct device *dev; | 
 | 	void __iomem *base; | 
 | 	struct clk_bulk_data *clks; | 
 | 	struct reset_control *rst; | 
 | 	const struct rockchip_data *data; | 
 | }; | 
 |  | 
 | static int rockchip_otp_reset(struct rockchip_otp *otp) | 
 | { | 
 | 	int ret; | 
 |  | 
 | 	ret = reset_control_assert(otp->rst); | 
 | 	if (ret) { | 
 | 		dev_err(otp->dev, "failed to assert otp phy %d\n", ret); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	udelay(2); | 
 |  | 
 | 	ret = reset_control_deassert(otp->rst); | 
 | 	if (ret) { | 
 | 		dev_err(otp->dev, "failed to deassert otp phy %d\n", ret); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int rockchip_otp_wait_status(struct rockchip_otp *otp, | 
 | 				    unsigned int reg, u32 flag) | 
 | { | 
 | 	u32 status = 0; | 
 | 	int ret; | 
 |  | 
 | 	ret = readl_poll_timeout_atomic(otp->base + reg, status, | 
 | 					(status & flag), 1, OTPC_TIMEOUT); | 
 | 	if (ret) | 
 | 		return ret; | 
 |  | 
 | 	/* clean int status */ | 
 | 	writel(flag, otp->base + reg); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int rockchip_otp_ecc_enable(struct rockchip_otp *otp, bool enable) | 
 | { | 
 | 	int ret = 0; | 
 |  | 
 | 	writel(SBPI_DAP_ADDR_MASK | (SBPI_DAP_ADDR << SBPI_DAP_ADDR_SHIFT), | 
 | 	       otp->base + OTPC_SBPI_CTRL); | 
 |  | 
 | 	writel(SBPI_CMD_VALID_MASK | 0x1, otp->base + OTPC_SBPI_CMD_VALID_PRE); | 
 | 	writel(SBPI_DAP_CMD_WRF | SBPI_DAP_REG_ECC, | 
 | 	       otp->base + OTPC_SBPI_CMD0_OFFSET); | 
 | 	if (enable) | 
 | 		writel(SBPI_ECC_ENABLE, otp->base + OTPC_SBPI_CMD1_OFFSET); | 
 | 	else | 
 | 		writel(SBPI_ECC_DISABLE, otp->base + OTPC_SBPI_CMD1_OFFSET); | 
 |  | 
 | 	writel(SBPI_ENABLE_MASK | SBPI_ENABLE, otp->base + OTPC_SBPI_CTRL); | 
 |  | 
 | 	ret = rockchip_otp_wait_status(otp, OTPC_INT_STATUS, OTPC_SBPI_DONE); | 
 | 	if (ret < 0) | 
 | 		dev_err(otp->dev, "timeout during ecc_enable\n"); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int px30_otp_read(void *context, unsigned int offset, | 
 | 			 void *val, size_t bytes) | 
 | { | 
 | 	struct rockchip_otp *otp = context; | 
 | 	u8 *buf = val; | 
 | 	int ret; | 
 |  | 
 | 	ret = rockchip_otp_reset(otp); | 
 | 	if (ret) { | 
 | 		dev_err(otp->dev, "failed to reset otp phy\n"); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	ret = rockchip_otp_ecc_enable(otp, false); | 
 | 	if (ret < 0) { | 
 | 		dev_err(otp->dev, "rockchip_otp_ecc_enable err\n"); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	writel(OTPC_USE_USER | OTPC_USE_USER_MASK, otp->base + OTPC_USER_CTRL); | 
 | 	udelay(5); | 
 | 	while (bytes--) { | 
 | 		writel(offset++ | OTPC_USER_ADDR_MASK, | 
 | 		       otp->base + OTPC_USER_ADDR); | 
 | 		writel(OTPC_USER_FSM_ENABLE | OTPC_USER_FSM_ENABLE_MASK, | 
 | 		       otp->base + OTPC_USER_ENABLE); | 
 | 		ret = rockchip_otp_wait_status(otp, OTPC_INT_STATUS, OTPC_USER_DONE); | 
 | 		if (ret < 0) { | 
 | 			dev_err(otp->dev, "timeout during read setup\n"); | 
 | 			goto read_end; | 
 | 		} | 
 | 		*buf++ = readb(otp->base + OTPC_USER_Q); | 
 | 	} | 
 |  | 
 | read_end: | 
 | 	writel(0x0 | OTPC_USE_USER_MASK, otp->base + OTPC_USER_CTRL); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int rk3588_otp_read(void *context, unsigned int offset, | 
 | 			   void *val, size_t bytes) | 
 | { | 
 | 	struct rockchip_otp *otp = context; | 
 | 	unsigned int addr_start, addr_end, addr_len; | 
 | 	int ret, i = 0; | 
 | 	u32 data; | 
 | 	u8 *buf; | 
 |  | 
 | 	addr_start = round_down(offset, RK3588_NBYTES) / RK3588_NBYTES; | 
 | 	addr_end = round_up(offset + bytes, RK3588_NBYTES) / RK3588_NBYTES; | 
 | 	addr_len = addr_end - addr_start; | 
 | 	addr_start += RK3588_NO_SECURE_OFFSET; | 
 |  | 
 | 	buf = kzalloc(array_size(addr_len, RK3588_NBYTES), GFP_KERNEL); | 
 | 	if (!buf) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	while (addr_len--) { | 
 | 		writel((addr_start << RK3588_ADDR_SHIFT) | | 
 | 		       (RK3588_BURST_NUM << RK3588_BURST_SHIFT), | 
 | 		       otp->base + RK3588_OTPC_AUTO_CTRL); | 
 | 		writel(RK3588_AUTO_EN, otp->base + RK3588_OTPC_AUTO_EN); | 
 |  | 
 | 		ret = rockchip_otp_wait_status(otp, RK3588_OTPC_INT_ST, | 
 | 					       RK3588_RD_DONE); | 
 | 		if (ret < 0) { | 
 | 			dev_err(otp->dev, "timeout during read setup\n"); | 
 | 			goto read_end; | 
 | 		} | 
 |  | 
 | 		data = readl(otp->base + RK3588_OTPC_DOUT0); | 
 | 		memcpy(&buf[i], &data, RK3588_NBYTES); | 
 |  | 
 | 		i += RK3588_NBYTES; | 
 | 		addr_start++; | 
 | 	} | 
 |  | 
 | 	memcpy(val, buf + offset % RK3588_NBYTES, bytes); | 
 |  | 
 | read_end: | 
 | 	kfree(buf); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int rockchip_otp_read(void *context, unsigned int offset, | 
 | 			     void *val, size_t bytes) | 
 | { | 
 | 	struct rockchip_otp *otp = context; | 
 | 	int ret; | 
 |  | 
 | 	if (!otp->data || !otp->data->reg_read) | 
 | 		return -EINVAL; | 
 |  | 
 | 	ret = clk_bulk_prepare_enable(otp->data->num_clks, otp->clks); | 
 | 	if (ret < 0) { | 
 | 		dev_err(otp->dev, "failed to prepare/enable clks\n"); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	ret = otp->data->reg_read(context, offset, val, bytes); | 
 |  | 
 | 	clk_bulk_disable_unprepare(otp->data->num_clks, otp->clks); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static struct nvmem_config otp_config = { | 
 | 	.name = "rockchip-otp", | 
 | 	.owner = THIS_MODULE, | 
 | 	.add_legacy_fixed_of_cells = true, | 
 | 	.type = NVMEM_TYPE_OTP, | 
 | 	.read_only = true, | 
 | 	.stride = 1, | 
 | 	.word_size = 1, | 
 | 	.reg_read = rockchip_otp_read, | 
 | }; | 
 |  | 
 | static const char * const px30_otp_clocks[] = { | 
 | 	"otp", "apb_pclk", "phy", | 
 | }; | 
 |  | 
 | static const struct rockchip_data px30_data = { | 
 | 	.size = 0x40, | 
 | 	.clks = px30_otp_clocks, | 
 | 	.num_clks = ARRAY_SIZE(px30_otp_clocks), | 
 | 	.reg_read = px30_otp_read, | 
 | }; | 
 |  | 
 | static const char * const rk3588_otp_clocks[] = { | 
 | 	"otp", "apb_pclk", "phy", "arb", | 
 | }; | 
 |  | 
 | static const struct rockchip_data rk3588_data = { | 
 | 	.size = 0x400, | 
 | 	.clks = rk3588_otp_clocks, | 
 | 	.num_clks = ARRAY_SIZE(rk3588_otp_clocks), | 
 | 	.reg_read = rk3588_otp_read, | 
 | }; | 
 |  | 
 | static const struct of_device_id rockchip_otp_match[] = { | 
 | 	{ | 
 | 		.compatible = "rockchip,px30-otp", | 
 | 		.data = &px30_data, | 
 | 	}, | 
 | 	{ | 
 | 		.compatible = "rockchip,rk3308-otp", | 
 | 		.data = &px30_data, | 
 | 	}, | 
 | 	{ | 
 | 		.compatible = "rockchip,rk3588-otp", | 
 | 		.data = &rk3588_data, | 
 | 	}, | 
 | 	{ /* sentinel */ }, | 
 | }; | 
 | MODULE_DEVICE_TABLE(of, rockchip_otp_match); | 
 |  | 
 | static int rockchip_otp_probe(struct platform_device *pdev) | 
 | { | 
 | 	struct device *dev = &pdev->dev; | 
 | 	struct rockchip_otp *otp; | 
 | 	const struct rockchip_data *data; | 
 | 	struct nvmem_device *nvmem; | 
 | 	int ret, i; | 
 |  | 
 | 	data = of_device_get_match_data(dev); | 
 | 	if (!data) | 
 | 		return dev_err_probe(dev, -EINVAL, "failed to get match data\n"); | 
 |  | 
 | 	otp = devm_kzalloc(&pdev->dev, sizeof(struct rockchip_otp), | 
 | 			   GFP_KERNEL); | 
 | 	if (!otp) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	otp->data = data; | 
 | 	otp->dev = dev; | 
 | 	otp->base = devm_platform_ioremap_resource(pdev, 0); | 
 | 	if (IS_ERR(otp->base)) | 
 | 		return dev_err_probe(dev, PTR_ERR(otp->base), | 
 | 				     "failed to ioremap resource\n"); | 
 |  | 
 | 	otp->clks = devm_kcalloc(dev, data->num_clks, sizeof(*otp->clks), | 
 | 				 GFP_KERNEL); | 
 | 	if (!otp->clks) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	for (i = 0; i < data->num_clks; ++i) | 
 | 		otp->clks[i].id = data->clks[i]; | 
 |  | 
 | 	ret = devm_clk_bulk_get(dev, data->num_clks, otp->clks); | 
 | 	if (ret) | 
 | 		return dev_err_probe(dev, ret, "failed to get clocks\n"); | 
 |  | 
 | 	otp->rst = devm_reset_control_array_get_exclusive(dev); | 
 | 	if (IS_ERR(otp->rst)) | 
 | 		return dev_err_probe(dev, PTR_ERR(otp->rst), | 
 | 				     "failed to get resets\n"); | 
 |  | 
 | 	otp_config.size = data->size; | 
 | 	otp_config.priv = otp; | 
 | 	otp_config.dev = dev; | 
 |  | 
 | 	nvmem = devm_nvmem_register(dev, &otp_config); | 
 | 	if (IS_ERR(nvmem)) | 
 | 		return dev_err_probe(dev, PTR_ERR(nvmem), | 
 | 				     "failed to register nvmem device\n"); | 
 | 	return 0; | 
 | } | 
 |  | 
 | static struct platform_driver rockchip_otp_driver = { | 
 | 	.probe = rockchip_otp_probe, | 
 | 	.driver = { | 
 | 		.name = "rockchip-otp", | 
 | 		.of_match_table = rockchip_otp_match, | 
 | 	}, | 
 | }; | 
 |  | 
 | module_platform_driver(rockchip_otp_driver); | 
 | MODULE_DESCRIPTION("Rockchip OTP driver"); | 
 | MODULE_LICENSE("GPL v2"); |