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Diffstat (limited to 'drivers/nvmem/nintendo-otp.c')
-rw-r--r--drivers/nvmem/nintendo-otp.c122
1 files changed, 122 insertions, 0 deletions
diff --git a/drivers/nvmem/nintendo-otp.c b/drivers/nvmem/nintendo-otp.c
new file mode 100644
index 0000000000..355e7f1fc6
--- /dev/null
+++ b/drivers/nvmem/nintendo-otp.c
@@ -0,0 +1,122 @@
+// 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 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;
+
+ priv->regs = devm_platform_ioremap_resource(pdev, 0);
+ 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");