[PATCH 2/3] thermal: K1: Add driver for K1 SoC thermal sensor
Shuwei Wu
shuweiwoo at 163.com
Wed Nov 26 10:44:08 PST 2025
The thermal sensor unit (TSU) on K1 supports monitoring five temperature
zones. The driver registers these sensors with the thermal framework
and supports standard operations:
- Reading temperature (millidegree Celsius)
- Setting high/low thresholds for interrupts
Signed-off-by: Shuwei Wu <shuweiwoo at 163.com>
---
drivers/thermal/Kconfig | 14 ++
drivers/thermal/Makefile | 1 +
drivers/thermal/k1_thermal.c | 307 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 322 insertions(+)
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index a09c188b9ad11377afe232d89c60504eb7000417..76095d2888980718b39470c09731092a21f7159b 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -495,6 +495,20 @@ config SPRD_THERMAL
Support for the Spreadtrum thermal sensor driver in the Linux thermal
framework.
+config K1_THERMAL
+ tristate "SpacemiT K1 thermal sensor driver"
+ depends on ARCH_SPACEMIT || COMPILE_TEST
+ help
+ This driver provides support for the thermal sensor unit (TSU)
+ integrated in the SpacemiT K1 SoC.
+
+ The TSU monitors temperatures for five thermal zones: soc, package,
+ gpu, cluster0, and cluster1. It supports reporting temperature
+ values and handling high/low threshold interrupts.
+
+ Say Y here if you want to enable thermal monitoring on SpacemiT K1.
+ If compiled as a module, it will be called k1_thermal.
+
config KHADAS_MCU_FAN_THERMAL
tristate "Khadas MCU controller FAN cooling support"
depends on OF
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index d7718978db245faffba98ff95a07c7bcbc776fd2..bf28ffe7a39f916acd608ea6d592c82049b0be17 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -65,6 +65,7 @@ obj-$(CONFIG_GENERIC_ADC_THERMAL) += thermal-generic-adc.o
obj-$(CONFIG_UNIPHIER_THERMAL) += uniphier_thermal.o
obj-$(CONFIG_AMLOGIC_THERMAL) += amlogic_thermal.o
obj-$(CONFIG_SPRD_THERMAL) += sprd_thermal.o
+obj-$(CONFIG_K1_THERMAL) += k1_thermal.o
obj-$(CONFIG_KHADAS_MCU_FAN_THERMAL) += khadas_mcu_fan.o
obj-$(CONFIG_LOONGSON2_THERMAL) += loongson2_thermal.o
obj-$(CONFIG_THERMAL_CORE_TESTING) += testing/
diff --git a/drivers/thermal/k1_thermal.c b/drivers/thermal/k1_thermal.c
new file mode 100644
index 0000000000000000000000000000000000000000..a0e9585cbc5a4e0f7c3a47debb3cfa8e82082d88
--- /dev/null
+++ b/drivers/thermal/k1_thermal.c
@@ -0,0 +1,307 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Thermal sensor driver for SpacemiT K1 SoC
+ *
+ * Copyright (C) 2025 Shuwei Wu <shuweiwoo at 163.com>
+ */
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/thermal.h>
+
+#include "thermal_hwmon.h"
+
+#define MAX_SENSOR_NUMBER 5
+#define TEMPERATURE_OFFSET 278
+
+#define K1_TSU_INT_EN 0x14
+#define K1_TSU_INT_CLR 0x10
+#define K1_TSU_INT_STA 0x18
+
+#define K1_TSU_INT_EN_MASK BIT(0)
+#define K1_TSU_INT_MASK(x) (GENMASK(2, 1) << ((x) * 2))
+
+#define K1_TSU_EN 0x8
+#define K1_TSU_EN_MASK(x) BIT(x)
+
+#define K1_TSU_DATA_BASE 0x20
+#define K1_TSU_DATA(x) (K1_TSU_DATA_BASE + ((x) / 2) * 4)
+#define K1_TSU_DATA_MASK(x) (((x) % 2) ? GENMASK(31, 16) : GENMASK(15, 0))
+#define K1_TSU_DATA_SHIFT(x) (((x) % 2) ? 16 : 0)
+
+#define K1_TSU_THRSH_BASE 0x40
+#define K1_TSU_THRSH(x) (K1_TSU_THRSH_BASE + ((x) * 4))
+#define K1_TSU_THRSH_HIGH_MASK GENMASK(31, 16)
+#define K1_TSU_THRSH_LOW_MASK GENMASK(15, 0)
+#define K1_TSU_THRSH_HIGH_SHIFT 16
+#define K1_TSU_THRSH_LOW_SHIFT 0
+
+#define K1_TSU_TIME 0x0C
+#define K1_TSU_TIME_MASK GENMASK(23, 0)
+#define K1_TSU_TIME_FILTER_PERIOD GENMASK(21, 20)
+#define K1_TSU_TIME_ADC_CNT_RST GENMASK(7, 4)
+#define K1_TSU_TIME_WAIT_REF_CNT GENMASK(3, 0)
+
+#define K1_TSU_PCTRL 0x00
+#define K1_TSU_PCTRL_RAW_SEL BIT(7)
+#define K1_TSU_PCTRL_TEMP_MODE BIT(3)
+#define K1_TSU_PCTRL_ENABLE BIT(0)
+
+#define K1_TSU_PCTRL_SW_CTRL GENMASK(21, 18)
+#define K1_TSU_PCTRL_CTUNE GENMASK(11, 8)
+#define K1_TSU_PCTRL_HW_AUTO_MODE BIT(23)
+
+#define K1_TSU_PCTRL2 0x04
+#define K1_TSU_PCTRL2_CLK_SEL_MASK GENMASK(15, 14)
+#define K1_TSU_PCTRL2_CLK_SEL_24M (0 << 14)
+
+struct k1_thermal_sensor {
+ struct k1_thermal_priv *priv;
+ struct thermal_zone_device *tzd;
+ int id;
+};
+
+struct k1_thermal_priv {
+ void __iomem *base;
+ struct device *dev;
+ struct clk *clk;
+ struct clk *bus_clk;
+ struct reset_control *reset;
+ struct k1_thermal_sensor sensors[MAX_SENSOR_NUMBER];
+};
+
+static int k1_init_sensors(struct platform_device *pdev)
+{
+ struct k1_thermal_priv *priv = platform_get_drvdata(pdev);
+ unsigned int temp;
+ int i;
+
+ /* Disable all the interrupts */
+ writel(0xffffffff, priv->base + K1_TSU_INT_EN);
+
+ /* Configure ADC sampling time and filter period */
+ temp = readl(priv->base + K1_TSU_TIME);
+ temp &= ~K1_TSU_TIME_MASK;
+ temp |= K1_TSU_TIME_FILTER_PERIOD |
+ K1_TSU_TIME_ADC_CNT_RST |
+ K1_TSU_TIME_WAIT_REF_CNT;
+ writel(temp, priv->base + K1_TSU_TIME);
+
+ /*
+ * Enable all sensors' auto mode, enable dither control,
+ * consecutive mode, and power up sensor.
+ */
+ temp = readl(priv->base + K1_TSU_PCTRL);
+ temp |= K1_TSU_PCTRL_RAW_SEL |
+ K1_TSU_PCTRL_TEMP_MODE |
+ K1_TSU_PCTRL_HW_AUTO_MODE |
+ K1_TSU_PCTRL_ENABLE;
+ temp &= ~K1_TSU_PCTRL_SW_CTRL;
+ temp &= ~K1_TSU_PCTRL_CTUNE;
+ writel(temp, priv->base + K1_TSU_PCTRL);
+
+ /* Select 24M clk for high speed mode */
+ temp = readl(priv->base + K1_TSU_PCTRL2);
+ temp &= ~K1_TSU_PCTRL2_CLK_SEL_MASK;
+ temp |= K1_TSU_PCTRL2_CLK_SEL_24M;
+ writel(temp, priv->base + K1_TSU_PCTRL2);
+
+ /* Enable thermal interrupt */
+ temp = readl(priv->base + K1_TSU_INT_EN);
+ temp |= K1_TSU_INT_EN_MASK;
+ writel(temp, priv->base + K1_TSU_INT_EN);
+
+ /* Enable each sensor */
+ for (i = 0; i < MAX_SENSOR_NUMBER; ++i) {
+ temp = readl(priv->base + K1_TSU_EN);
+ temp &= ~K1_TSU_EN_MASK(i);
+ temp |= K1_TSU_EN_MASK(i);
+ writel(temp, priv->base + K1_TSU_EN);
+ }
+
+ return 0;
+}
+
+static void k1_enable_sensor_irq(struct k1_thermal_sensor *sensor)
+{
+ struct k1_thermal_priv *priv = sensor->priv;
+ unsigned int temp;
+
+ temp = readl(priv->base + K1_TSU_INT_CLR);
+ temp |= K1_TSU_INT_MASK(sensor->id);
+ writel(temp, priv->base + K1_TSU_INT_CLR);
+
+ temp = readl(priv->base + K1_TSU_INT_EN);
+ temp &= ~K1_TSU_INT_MASK(sensor->id);
+ writel(temp, priv->base + K1_TSU_INT_EN);
+}
+
+/*
+ * The conversion formula used is:
+ * T(m°C) = (((raw_value & mask) >> shift) - TEMPERATURE_OFFSET) * 1000
+ */
+static int k1_thermal_get_temp(struct thermal_zone_device *tz, int *temp)
+{
+ struct k1_thermal_sensor *sensor = thermal_zone_device_priv(tz);
+ struct k1_thermal_priv *priv = sensor->priv;
+
+ *temp = readl(priv->base + K1_TSU_DATA(sensor->id));
+ *temp &= K1_TSU_DATA_MASK(sensor->id);
+ *temp >>= K1_TSU_DATA_SHIFT(sensor->id);
+
+ *temp -= TEMPERATURE_OFFSET;
+
+ *temp *= 1000;
+
+ return 0;
+}
+
+/*
+ * For each sensor, the hardware threshold register is 32 bits:
+ * - Lower 16 bits [15:0] configure the low threshold temperature.
+ * - Upper 16 bits [31:16] configure the high threshold temperature.
+ */
+static int k1_thermal_set_trips(struct thermal_zone_device *tz, int low, int high)
+{
+ struct k1_thermal_sensor *sensor = thermal_zone_device_priv(tz);
+ struct k1_thermal_priv *priv = sensor->priv;
+ int high_code = high;
+ int low_code = low;
+ unsigned int temp;
+
+ if (low >= high)
+ return -EINVAL;
+
+ if (low < 0)
+ low_code = 0;
+
+ high_code = high_code / 1000 + TEMPERATURE_OFFSET;
+ temp = readl(priv->base + K1_TSU_THRSH(sensor->id));
+ temp &= ~K1_TSU_THRSH_HIGH_MASK;
+ temp |= (high_code << K1_TSU_THRSH_HIGH_SHIFT);
+ writel(temp, priv->base + K1_TSU_THRSH(sensor->id));
+
+ low_code = low_code / 1000 + TEMPERATURE_OFFSET;
+ temp = readl(priv->base + K1_TSU_THRSH(sensor->id));
+ temp &= ~K1_TSU_THRSH_LOW_MASK;
+ temp |= (low_code << K1_TSU_THRSH_LOW_SHIFT);
+ writel(temp, priv->base + K1_TSU_THRSH(sensor->id));
+
+ return 0;
+}
+
+static const struct thermal_zone_device_ops k1_thermal_ops = {
+ .get_temp = k1_thermal_get_temp,
+ .set_trips = k1_thermal_set_trips,
+};
+
+static irqreturn_t k1_thermal_irq_thread(int irq, void *data)
+{
+ struct k1_thermal_priv *priv = (struct k1_thermal_priv *)data;
+ int msk, status, i;
+
+ status = readl(priv->base + K1_TSU_INT_STA);
+
+ for (i = 0; i < MAX_SENSOR_NUMBER; i++) {
+ if (status & K1_TSU_INT_MASK(i)) {
+ msk = readl(priv->base + K1_TSU_INT_CLR);
+ msk |= K1_TSU_INT_MASK(i);
+ writel(msk, priv->base + K1_TSU_INT_CLR);
+ /* Notify thermal framework to update trips */
+ thermal_zone_device_update(priv->sensors[i].tzd, THERMAL_EVENT_UNSPECIFIED);
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int k1_thermal_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct k1_thermal_priv *priv;
+ int i, irq, ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = dev;
+ platform_set_drvdata(pdev, priv);
+
+ priv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ priv->reset = devm_reset_control_get_exclusive_deasserted(dev, NULL);
+ if (IS_ERR(priv->reset))
+ return dev_err_probe(dev, PTR_ERR(priv->reset),
+ "Failed to get/deassert reset control\n");
+
+ priv->clk = devm_clk_get_enabled(dev, "core");
+ if (IS_ERR(priv->clk))
+ return dev_err_probe(dev, PTR_ERR(priv->clk),
+ "Failed to get core clock\n");
+
+ priv->bus_clk = devm_clk_get_enabled(dev, "bus");
+ if (IS_ERR(priv->bus_clk))
+ return dev_err_probe(dev, PTR_ERR(priv->bus_clk),
+ "Failed to get bus clock\n");
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ ret = k1_init_sensors(pdev);
+
+ for (i = 0; i < MAX_SENSOR_NUMBER; ++i) {
+ priv->sensors[i].id = i;
+ priv->sensors[i].priv = priv;
+ priv->sensors[i].tzd = devm_thermal_of_zone_register(dev,
+ i, priv->sensors + i,
+ &k1_thermal_ops);
+ if (IS_ERR(priv->sensors[i].tzd))
+ return dev_err_probe(dev, PTR_ERR(priv->sensors[i].tzd),
+ "Failed to register thermal zone: %d\n", i);
+
+ /* Attach sysfs hwmon attributes for userspace monitoring */
+ ret = devm_thermal_add_hwmon_sysfs(dev, priv->sensors[i].tzd);
+ if (ret)
+ dev_warn(dev, "Failed to add hwmon sysfs attributes\n");
+
+ k1_enable_sensor_irq(priv->sensors + i);
+ }
+
+ ret = devm_request_threaded_irq(dev, irq, NULL,
+ k1_thermal_irq_thread,
+ IRQF_ONESHOT, "k1_thermal", priv);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Failed to request IRQ\n");
+
+ return 0;
+}
+
+static const struct of_device_id k1_thermal_dt_ids[] = {
+ { .compatible = "spacemit,k1-thermal" },
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, k1_thermal_dt_ids);
+
+static struct platform_driver k1_thermal_driver = {
+ .driver = {
+ .name = "k1_thermal",
+ .of_match_table = k1_thermal_dt_ids,
+ },
+ .probe = k1_thermal_probe,
+};
+module_platform_driver(k1_thermal_driver);
+
+MODULE_DESCRIPTION("SpacemiT K1 Thermal Sensor Driver");
+MODULE_AUTHOR("Shuwei Wu <shuweiwoo at 163.com>");
+MODULE_LICENSE("GPL");
--
2.51.0
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