@@ -298,6 +298,19 @@ config NVMEM_SNVS_LPGPR
This driver can also be built as a module. If so, the module
will be called nvmem-snvs-lpgpr.
+config NVMEM_SOPHGO_EFUSE
+ tristate "Sophgo eFuse support"
+ depends on ARCH_SOPHGO || COMPILE_TEST
+ default ARCH_SOPHGO
+ help
+ Say y here to enable support for reading eFuses on Sophgo SoCs
+ such as the CV1800B. These are e.g. used to store factory programmed
+ calibration data required for the builtin ethernet PHY.
+
+ This driver can also be built as a module. If so, the module will
+ be called nvmem-sophgo-efuse.
+
+
config NVMEM_SPMI_SDAM
tristate "SPMI SDAM Support"
depends on SPMI
@@ -60,6 +60,8 @@ obj-$(CONFIG_NVMEM_SC27XX_EFUSE) += nvmem-sc27xx-efuse.o
nvmem-sc27xx-efuse-y := sc27xx-efuse.o
obj-$(CONFIG_NVMEM_SNVS_LPGPR) += nvmem_snvs_lpgpr.o
nvmem_snvs_lpgpr-y := snvs_lpgpr.o
+obj-$(CONFIG_NVMEM_SOPHGO_EFUSE) += nvmem-sophgo-efuse.o
+nvmem-sophgo-efuse-y := sophgo-efuse.o
obj-$(CONFIG_NVMEM_SPMI_SDAM) += nvmem_qcom-spmi-sdam.o
nvmem_qcom-spmi-sdam-y += qcom-spmi-sdam.o
obj-$(CONFIG_NVMEM_SPRD_EFUSE) += nvmem_sprd_efuse.o
new file mode 100644
@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Sophgo SoC eFuse driver
+ *
+ * Copyright (C) 2023 Jisheng Zhang <jszhang@kernel.org>
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/nvmem-provider.h>
+#include <linux/platform_device.h>
+
+#define CV1800B_EFUSE_CONTENT_BASE 0x100
+#define CV1800B_EFUSE_CONTENT_SIZE 0x100
+
+struct sophgo_efuses_priv {
+ void __iomem *base;
+ struct clk *clk;
+};
+
+static int sophgo_efuses_read(void *context, unsigned int offset, void *val,
+ size_t bytes)
+{
+ struct sophgo_efuses_priv *priv = context;
+ u32 *dst = val;
+ int ret;
+
+ ret = clk_prepare_enable(priv->clk);
+ if (ret < 0)
+ return ret;
+
+ while (bytes >= sizeof(u32)) {
+ *dst++ = readl_relaxed(priv->base + CV1800B_EFUSE_CONTENT_BASE + offset);
+ bytes -= sizeof(u32);
+ offset += sizeof(u32);
+ }
+
+ clk_disable_unprepare(priv->clk);
+
+ return 0;
+}
+
+static int sophgo_efuses_probe(struct platform_device *pdev)
+{
+ struct sophgo_efuses_priv *priv;
+ struct resource *res;
+ struct nvmem_config config = {
+ .dev = &pdev->dev,
+ .add_legacy_fixed_of_cells = true,
+ .read_only = true,
+ .reg_read = sophgo_efuses_read,
+ .stride = sizeof(u32),
+ .word_size = sizeof(u32),
+ .name = "sophgo_efuse_nvmem",
+ .id = NVMEM_DEVID_AUTO,
+ .root_only = true,
+ };
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ priv->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(priv->clk))
+ return PTR_ERR(priv->clk);
+
+ config.priv = priv;
+ config.size = CV1800B_EFUSE_CONTENT_SIZE;
+
+ return PTR_ERR_OR_ZERO(devm_nvmem_register(config.dev, &config));
+}
+
+static const struct of_device_id sophgo_efuses_of_match[] = {
+ { .compatible = "sophgo,cv1800b-efuse", },
+ {}
+};
+
+MODULE_DEVICE_TABLE(of, sophgo_efuses_of_match);
+
+static struct platform_driver sophgo_efuses_driver = {
+ .driver = {
+ .name = "sophgo_efuse",
+ .of_match_table = sophgo_efuses_of_match,
+ },
+ .probe = sophgo_efuses_probe,
+};
+
+module_platform_driver(sophgo_efuses_driver);
+
+MODULE_AUTHOR("Jisheng Zhang <jszhang@kernel.org>");
+MODULE_LICENSE("GPL");
Sophgo SoCs such as CV1800B contain eFuses used to store factory-programmed data such as calibration values for the built-in ethernet PHY. As for CV1800B, HW automatically loads the eFuse content into CONTENT base registers which are organized as 32bit values exposed as MMIO. Currently, add read support for the eFuse. This is a preparation step for supporting the built-in ethernet phy. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> --- drivers/nvmem/Kconfig | 13 +++++ drivers/nvmem/Makefile | 2 + drivers/nvmem/sophgo-efuse.c | 97 ++++++++++++++++++++++++++++++++++++ 3 files changed, 112 insertions(+) create mode 100644 drivers/nvmem/sophgo-efuse.c