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(matches: nintendo_otp_of_table, dev); |
79 | struct nvmem_device *nvmem; |
80 | struct nintendo_otp_priv *priv; |
81 | |
82 | struct nvmem_config config = { |
83 | .stride = WORD_SIZE, |
84 | .word_size = WORD_SIZE, |
85 | .reg_read = nintendo_otp_reg_read, |
86 | .read_only = true, |
87 | .root_only = true, |
88 | }; |
89 | |
90 | priv = devm_kzalloc(dev, size: sizeof(*priv), GFP_KERNEL); |
91 | if (!priv) |
92 | return -ENOMEM; |
93 | |
94 | priv->regs = devm_platform_ioremap_resource(pdev, index: 0); |
95 | if (IS_ERR(ptr: priv->regs)) |
96 | return PTR_ERR(ptr: priv->regs); |
97 | |
98 | if (of_id->data) { |
99 | const struct nintendo_otp_devtype_data *data = of_id->data; |
100 | config.name = data->name; |
101 | config.size = data->num_banks * BANK_SIZE; |
102 | } |
103 | |
104 | config.dev = dev; |
105 | config.priv = priv; |
106 | |
107 | nvmem = devm_nvmem_register(dev, cfg: &config); |
108 | |
109 | return PTR_ERR_OR_ZERO(ptr: nvmem); |
110 | } |
111 | |
112 | static struct platform_driver nintendo_otp_driver = { |
113 | .probe = nintendo_otp_probe, |
114 | .driver = { |
115 | .name = "nintendo-otp" , |
116 | .of_match_table = nintendo_otp_of_table, |
117 | }, |
118 | }; |
119 | module_platform_driver(nintendo_otp_driver); |
120 | MODULE_AUTHOR("Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>" ); |
121 | MODULE_DESCRIPTION("Nintendo Wii and Wii U OTP driver" ); |
122 | MODULE_LICENSE("GPL v2" ); |
123 | |