diff options
Diffstat (limited to 'drivers/nvmem/nintendo-otp.c')
| -rw-r--r-- | drivers/nvmem/nintendo-otp.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/drivers/nvmem/nintendo-otp.c b/drivers/nvmem/nintendo-otp.c new file mode 100644 index 000000000000..33961b17f9f1 --- /dev/null +++ b/drivers/nvmem/nintendo-otp.c @@ -0,0 +1,124 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Nintendo Wii and Wii U OTP driver + * + * This is a driver exposing the OTP of a Nintendo Wii or Wii U console. + * + * This memory contains common and per-console keys, signatures and + * related data required to access peripherals. + * + * Based on reversed documentation from https://wiiubrew.org/wiki/Hardware/OTP + * + * Copyright (C) 2021 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr> + */ + +#include <linux/device.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/nvmem-provider.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> + +#define HW_OTPCMD 0 +#define HW_OTPDATA 4 +#define OTP_READ 0x80000000 +#define BANK_SIZE 128 +#define WORD_SIZE 4 + +struct nintendo_otp_priv { + void __iomem *regs; +}; + +struct nintendo_otp_devtype_data { + const char *name; + unsigned int num_banks; +}; + +static const struct nintendo_otp_devtype_data hollywood_otp_data = { + .name = "wii-otp", + .num_banks = 1, +}; + +static const struct nintendo_otp_devtype_data latte_otp_data = { + .name = "wiiu-otp", + .num_banks = 8, +}; + +static int nintendo_otp_reg_read(void *context, + unsigned int reg, void *_val, size_t bytes) +{ + struct nintendo_otp_priv *priv = context; + u32 *val = _val; + int words = bytes / WORD_SIZE; + u32 bank, addr; + + while (words--) { + bank = (reg / BANK_SIZE) << 8; + addr = (reg / WORD_SIZE) % (BANK_SIZE / WORD_SIZE); + iowrite32be(OTP_READ | bank | addr, priv->regs + HW_OTPCMD); + *val++ = ioread32be(priv->regs + HW_OTPDATA); + reg += WORD_SIZE; + } + + return 0; +} + +static const struct of_device_id nintendo_otp_of_table[] = { + { .compatible = "nintendo,hollywood-otp", .data = &hollywood_otp_data }, + { .compatible = "nintendo,latte-otp", .data = &latte_otp_data }, + {/* sentinel */}, +}; +MODULE_DEVICE_TABLE(of, nintendo_otp_of_table); + +static int nintendo_otp_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const struct of_device_id *of_id = + of_match_device(nintendo_otp_of_table, dev); + struct resource *res; + struct nvmem_device *nvmem; + struct nintendo_otp_priv *priv; + + struct nvmem_config config = { + .stride = WORD_SIZE, + .word_size = WORD_SIZE, + .reg_read = nintendo_otp_reg_read, + .read_only = true, + .root_only = true, + }; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->regs = devm_ioremap_resource(dev, res); + if (IS_ERR(priv->regs)) + return PTR_ERR(priv->regs); + + if (of_id->data) { + const struct nintendo_otp_devtype_data *data = of_id->data; + config.name = data->name; + config.size = data->num_banks * BANK_SIZE; + } + + config.dev = dev; + config.priv = priv; + + nvmem = devm_nvmem_register(dev, &config); + + return PTR_ERR_OR_ZERO(nvmem); +} + +static struct platform_driver nintendo_otp_driver = { + .probe = nintendo_otp_probe, + .driver = { + .name = "nintendo-otp", + .of_match_table = nintendo_otp_of_table, + }, +}; +module_platform_driver(nintendo_otp_driver); +MODULE_AUTHOR("Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>"); +MODULE_DESCRIPTION("Nintendo Wii and Wii U OTP driver"); +MODULE_LICENSE("GPL v2"); |