diff options
Diffstat (limited to 'drivers/nvmem/sunplus-ocotp.c')
| -rw-r--r-- | drivers/nvmem/sunplus-ocotp.c | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/drivers/nvmem/sunplus-ocotp.c b/drivers/nvmem/sunplus-ocotp.c new file mode 100644 index 000000000..f85350b17 --- /dev/null +++ b/drivers/nvmem/sunplus-ocotp.c @@ -0,0 +1,231 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * The OCOTP driver for Sunplus SP7021 + * + * Copyright (C) 2019 Sunplus Technology Inc., All rights reserved. + */ + +#include <linux/bitfield.h> +#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/of_device.h> +#include <linux/platform_device.h> + +/* + * OTP memory + * Each bank contains 4 words (32 bits). + * Bank 0 starts at offset 0 from the base. + */ + +#define OTP_WORDS_PER_BANK 4 +#define OTP_WORD_SIZE sizeof(u32) +#define OTP_BIT_ADDR_OF_BANK (8 * OTP_WORD_SIZE * OTP_WORDS_PER_BANK) +#define QAC628_OTP_NUM_BANKS 8 +#define QAC628_OTP_SIZE (QAC628_OTP_NUM_BANKS * OTP_WORDS_PER_BANK * OTP_WORD_SIZE) +#define OTP_READ_TIMEOUT_US 200000 + +/* HB_GPIO */ +#define ADDRESS_8_DATA 0x20 + +/* OTP_RX */ +#define OTP_CONTROL_2 0x48 +#define OTP_RD_PERIOD GENMASK(15, 8) +#define OTP_RD_PERIOD_MASK ~GENMASK(15, 8) +#define CPU_CLOCK FIELD_PREP(OTP_RD_PERIOD, 30) +#define SEL_BAK_KEY2 BIT(5) +#define SEL_BAK_KEY2_MASK ~BIT(5) +#define SW_TRIM_EN BIT(4) +#define SW_TRIM_EN_MASK ~BIT(4) +#define SEL_BAK_KEY BIT(3) +#define SEL_BAK_KEY_MASK ~BIT(3) +#define OTP_READ BIT(2) +#define OTP_LOAD_SECURE_DATA BIT(1) +#define OTP_LOAD_SECURE_DATA_MASK ~BIT(1) +#define OTP_DO_CRC BIT(0) +#define OTP_DO_CRC_MASK ~BIT(0) +#define OTP_STATUS 0x4c +#define OTP_READ_DONE BIT(4) +#define OTP_READ_DONE_MASK ~BIT(4) +#define OTP_LOAD_SECURE_DONE_MASK ~BIT(2) +#define OTP_READ_ADDRESS 0x50 + +enum base_type { + HB_GPIO, + OTPRX, + BASEMAX, +}; + +struct sp_ocotp_priv { + struct device *dev; + void __iomem *base[BASEMAX]; + struct clk *clk; +}; + +struct sp_ocotp_data { + int size; +}; + +static const struct sp_ocotp_data sp_otp_v0 = { + .size = QAC628_OTP_SIZE, +}; + +static int sp_otp_read_real(struct sp_ocotp_priv *otp, int addr, char *value) +{ + unsigned int addr_data; + unsigned int byte_shift; + unsigned int status; + int ret; + + addr_data = addr % (OTP_WORD_SIZE * OTP_WORDS_PER_BANK); + addr_data = addr_data / OTP_WORD_SIZE; + + byte_shift = addr % (OTP_WORD_SIZE * OTP_WORDS_PER_BANK); + byte_shift = byte_shift % OTP_WORD_SIZE; + + addr = addr / (OTP_WORD_SIZE * OTP_WORDS_PER_BANK); + addr = addr * OTP_BIT_ADDR_OF_BANK; + + writel(readl(otp->base[OTPRX] + OTP_STATUS) & OTP_READ_DONE_MASK & + OTP_LOAD_SECURE_DONE_MASK, otp->base[OTPRX] + OTP_STATUS); + writel(addr, otp->base[OTPRX] + OTP_READ_ADDRESS); + writel(readl(otp->base[OTPRX] + OTP_CONTROL_2) | OTP_READ, + otp->base[OTPRX] + OTP_CONTROL_2); + writel(readl(otp->base[OTPRX] + OTP_CONTROL_2) & SEL_BAK_KEY2_MASK & SW_TRIM_EN_MASK + & SEL_BAK_KEY_MASK & OTP_LOAD_SECURE_DATA_MASK & OTP_DO_CRC_MASK, + otp->base[OTPRX] + OTP_CONTROL_2); + writel((readl(otp->base[OTPRX] + OTP_CONTROL_2) & OTP_RD_PERIOD_MASK) | CPU_CLOCK, + otp->base[OTPRX] + OTP_CONTROL_2); + + ret = readl_poll_timeout(otp->base[OTPRX] + OTP_STATUS, status, + status & OTP_READ_DONE, 10, OTP_READ_TIMEOUT_US); + + if (ret < 0) + return ret; + + *value = (readl(otp->base[HB_GPIO] + ADDRESS_8_DATA + addr_data * OTP_WORD_SIZE) + >> (8 * byte_shift)) & 0xff; + + return ret; +} + +static int sp_ocotp_read(void *priv, unsigned int offset, void *value, size_t bytes) +{ + struct sp_ocotp_priv *otp = priv; + unsigned int addr; + char *buf = value; + char val[4]; + int ret; + + ret = clk_enable(otp->clk); + if (ret) + return ret; + + *buf = 0; + for (addr = offset; addr < (offset + bytes); addr++) { + ret = sp_otp_read_real(otp, addr, val); + if (ret < 0) { + dev_err(otp->dev, "OTP read fail:%d at %d", ret, addr); + goto disable_clk; + } + + *buf++ = *val; + } + +disable_clk: + clk_disable(otp->clk); + + return ret; +} + +static struct nvmem_config sp_ocotp_nvmem_config = { + .name = "sp-ocotp", + .read_only = true, + .word_size = 1, + .size = QAC628_OTP_SIZE, + .stride = 1, + .reg_read = sp_ocotp_read, + .owner = THIS_MODULE, +}; + +static int sp_ocotp_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct nvmem_device *nvmem; + struct sp_ocotp_priv *otp; + struct resource *res; + int ret; + + otp = devm_kzalloc(dev, sizeof(*otp), GFP_KERNEL); + if (!otp) + return -ENOMEM; + + otp->dev = dev; + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "hb_gpio"); + otp->base[HB_GPIO] = devm_ioremap_resource(dev, res); + if (IS_ERR(otp->base[HB_GPIO])) + return PTR_ERR(otp->base[HB_GPIO]); + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "otprx"); + otp->base[OTPRX] = devm_ioremap_resource(dev, res); + if (IS_ERR(otp->base[OTPRX])) + return PTR_ERR(otp->base[OTPRX]); + + otp->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(otp->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(otp->clk), + "devm_clk_get fail\n"); + + ret = clk_prepare(otp->clk); + if (ret < 0) { + dev_err(dev, "failed to prepare clk: %d\n", ret); + return ret; + } + + sp_ocotp_nvmem_config.priv = otp; + sp_ocotp_nvmem_config.dev = dev; + + nvmem = devm_nvmem_register(dev, &sp_ocotp_nvmem_config); + if (IS_ERR(nvmem)) { + ret = dev_err_probe(&pdev->dev, PTR_ERR(nvmem), + "register nvmem device fail\n"); + goto err; + } + + platform_set_drvdata(pdev, nvmem); + + dev_dbg(dev, "banks:%d x wpb:%d x wsize:%d = %d", + (int)QAC628_OTP_NUM_BANKS, (int)OTP_WORDS_PER_BANK, + (int)OTP_WORD_SIZE, (int)QAC628_OTP_SIZE); + + return 0; +err: + clk_unprepare(otp->clk); + return ret; +} + +static const struct of_device_id sp_ocotp_dt_ids[] = { + { .compatible = "sunplus,sp7021-ocotp", .data = &sp_otp_v0 }, + { } +}; +MODULE_DEVICE_TABLE(of, sp_ocotp_dt_ids); + +static struct platform_driver sp_otp_driver = { + .probe = sp_ocotp_probe, + .driver = { + .name = "sunplus,sp7021-ocotp", + .of_match_table = sp_ocotp_dt_ids, + } +}; +module_platform_driver(sp_otp_driver); + +MODULE_AUTHOR("Vincent Shih <vincent.sunplus@gmail.com>"); +MODULE_DESCRIPTION("Sunplus On-Chip OTP driver"); +MODULE_LICENSE("GPL"); + |