1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Nintendo Wii and Wii U OTP driver 4 * 5 * This is a driver exposing the OTP of a Nintendo Wii or Wii U console. 6 * 7 * This memory contains common and per-console keys, signatures and 8 * related data required to access peripherals. 9 * 10 * Based on reversed documentation from https://wiiubrew.org/wiki/Hardware/OTP 11 * 12 * Copyright (C) 2021 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr> 13 */ 14 15 #include <linux/device.h> 16 #include <linux/io.h> 17 #include <linux/module.h> 18 #include <linux/mod_devicetable.h> 19 #include <linux/nvmem-provider.h> 20 #include <linux/of_device.h> 21 #include <linux/platform_device.h> 22 23 #define HW_OTPCMD 0 24 #define HW_OTPDATA 4 25 #define OTP_READ 0x80000000 26 #define BANK_SIZE 128 27 #define WORD_SIZE 4 28 29 struct nintendo_otp_priv { 30 void __iomem *regs; 31 }; 32 33 struct nintendo_otp_devtype_data { 34 const char *name; 35 unsigned int num_banks; 36 }; 37 38 static const struct nintendo_otp_devtype_data hollywood_otp_data = { 39 .name = "wii-otp", 40 .num_banks = 1, 41 }; 42 43 static const struct nintendo_otp_devtype_data latte_otp_data = { 44 .name = "wiiu-otp", 45 .num_banks = 8, 46 }; 47 48 static int nintendo_otp_reg_read(void *context, 49 unsigned int reg, void *_val, size_t bytes) 50 { 51 struct nintendo_otp_priv *priv = context; 52 u32 *val = _val; 53 int words = bytes / WORD_SIZE; 54 u32 bank, addr; 55 56 while (words--) { 57 bank = (reg / BANK_SIZE) << 8; 58 addr = (reg / WORD_SIZE) % (BANK_SIZE / WORD_SIZE); 59 iowrite32be(OTP_READ | bank | addr, priv->regs + HW_OTPCMD); 60 *val++ = ioread32be(priv->regs + HW_OTPDATA); 61 reg += WORD_SIZE; 62 } 63 64 return 0; 65 } 66 67 static const struct of_device_id nintendo_otp_of_table[] = { 68 { .compatible = "nintendo,hollywood-otp", .data = &hollywood_otp_data }, 69 { .compatible = "nintendo,latte-otp", .data = &latte_otp_data }, 70 {/* sentinel */}, 71 }; 72 MODULE_DEVICE_TABLE(of, nintendo_otp_of_table); 73 74 static int nintendo_otp_probe(struct platform_device *pdev) 75 { 76 struct device *dev = &pdev->dev; 77 const struct of_device_id *of_id = 78 of_match_device(nintendo_otp_of_table, dev); 79 struct resource *res; 80 struct nvmem_device *nvmem; 81 struct nintendo_otp_priv *priv; 82 83 struct nvmem_config config = { 84 .stride = WORD_SIZE, 85 .word_size = WORD_SIZE, 86 .reg_read = nintendo_otp_reg_read, 87 .read_only = true, 88 .root_only = true, 89 }; 90 91 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 92 if (!priv) 93 return -ENOMEM; 94 95 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 96 priv->regs = devm_ioremap_resource(dev, res); 97 if (IS_ERR(priv->regs)) 98 return PTR_ERR(priv->regs); 99 100 if (of_id->data) { 101 const struct nintendo_otp_devtype_data *data = of_id->data; 102 config.name = data->name; 103 config.size = data->num_banks * BANK_SIZE; 104 } 105 106 config.dev = dev; 107 config.priv = priv; 108 109 nvmem = devm_nvmem_register(dev, &config); 110 111 return PTR_ERR_OR_ZERO(nvmem); 112 } 113 114 static struct platform_driver nintendo_otp_driver = { 115 .probe = nintendo_otp_probe, 116 .driver = { 117 .name = "nintendo-otp", 118 .of_match_table = nintendo_otp_of_table, 119 }, 120 }; 121 module_platform_driver(nintendo_otp_driver); 122 MODULE_AUTHOR("Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>"); 123 MODULE_DESCRIPTION("Nintendo Wii and Wii U OTP driver"); 124 MODULE_LICENSE("GPL v2"); 125