[PATCH v2 3/3] thermal: loongson2: add thermal management support

From: Yinbo Zhu
Date: Tue Sep 20 2022 - 21:56:32 EST


This patch adds the support for loongson2 thermal sensor controller,
which can support maximum 4 sensors.

It's based on thermal of framework:
- Trip points defined in device tree.
- Cpufreq as cooling device registered in loongson2 cpufreq driver.
- Pwm fan as cooling device registered in hwmon pwm-fan driver.

Signed-off-by: zhanghongchen <zhanghongchen@xxxxxxxxxxx>
Signed-off-by: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
---
Change in v2:
1. Remove error msg printing when addr ioremap has error.
2. Make loongson2 thermal driver was built-in by default.
3. Replace ls2k with loongson2.
4. Remove CONFIG_PM_SLEEP and set pm function type was
__maybe_unused.

drivers/thermal/Kconfig | 10 ++
drivers/thermal/Makefile | 1 +
drivers/thermal/loongson2_thermal.c | 238 ++++++++++++++++++++++++++++
3 files changed, 249 insertions(+)
create mode 100644 drivers/thermal/loongson2_thermal.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index e052dae614eb..6b60397e96a1 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -504,4 +504,14 @@ config KHADAS_MCU_FAN_THERMAL
If you say yes here you get support for the FAN controlled
by the Microcontroller found on the Khadas VIM boards.

+config LOONGSON2_THERMAL
+ tristate "Loongson2 SOC series thermal driver"
+ depends on OF
+ default y
+ help
+ Support for Thermal driver found on Loongson2 SOC series platforms.
+ It supports one critical trip point and one passive trip point. The
+ cpufreq and the pwm fan is used as the cooling device to throttle
+ CPUs when the passive trip is crossed.
+
endif
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index def8e1a0399c..e99f839126fa 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -61,3 +61,4 @@ obj-$(CONFIG_UNIPHIER_THERMAL) += uniphier_thermal.o
obj-$(CONFIG_AMLOGIC_THERMAL) += amlogic_thermal.o
obj-$(CONFIG_SPRD_THERMAL) += sprd_thermal.o
obj-$(CONFIG_KHADAS_MCU_FAN_THERMAL) += khadas_mcu_fan.o
+obj-$(CONFIG_LOONGSON2_THERMAL) += loongson2_thermal.o
diff --git a/drivers/thermal/loongson2_thermal.c b/drivers/thermal/loongson2_thermal.c
new file mode 100644
index 000000000000..d685c2ab1c0a
--- /dev/null
+++ b/drivers/thermal/loongson2_thermal.c
@@ -0,0 +1,238 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Author: zhanghongchen <zhanghongchen@xxxxxxxxxxx>
+ * Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
+ * Copyright (C) 2022-2023 Loongson Technology Corporation Limited
+ */
+
+#include <linux/cpufreq.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/of_device.h>
+#include <linux/thermal.h>
+#include "thermal_hwmon.h"
+
+#define LOONGSON2_SOC_DEFAULT_SENSOR 0
+#define LOONGSON2_SOC_MAX_SENSOR_NUM 4
+
+#define LOONGSON2_TSENSOR_CTRL_HI 0x0
+#define LOONGSON2_TSENSOR_CTRL_LO 0x8
+#define LOONGSON2_TSENSOR_STATUS 0x10
+#define LOONGSON2_TSENSOR_OUT 0x14
+
+struct loongson2_thermal_data {
+ struct thermal_zone_device *tzd;
+ int irq;
+ int id;
+ void __iomem *regs;
+ struct platform_device *pdev;
+ u16 ctrl_low_val;
+ u16 ctrl_hi_val;
+};
+
+/**
+ * @low : temperature in degree
+ * @high: temperature in degree
+ */
+static int loongson2_thermal_set(struct loongson2_thermal_data *data,
+ int low, int high, bool enable)
+{
+ u64 reg_ctrl = 0;
+ int reg_off = data->id * 2;
+
+ if (low > high)
+ return -EINVAL;
+
+ low = low < -100 ? -100 : low;
+ high = high > 155 ? 155 : high;
+
+ low += 100;
+ high += 100;
+
+ reg_ctrl |= low;
+ reg_ctrl |= enable ? 0x100 : 0;
+ writew(reg_ctrl, data->regs + LOONGSON2_TSENSOR_CTRL_LO + reg_off);
+
+ reg_ctrl = 0;
+ reg_ctrl |= high;
+ reg_ctrl |= enable ? 0x100 : 0;
+ writew(reg_ctrl, data->regs + LOONGSON2_TSENSOR_CTRL_HI + reg_off);
+
+ return 0;
+}
+
+static int loongson2_thermal_get_temp(void *__data, int *temp)
+{
+ struct loongson2_thermal_data *data = __data;
+ u32 reg_val;
+
+ reg_val = readl(data->regs + LOONGSON2_TSENSOR_OUT);
+ *temp = ((reg_val & 0xff) - 100) * 1000;
+
+ return 0;
+}
+
+static irqreturn_t loongson2_thermal_alarm_irq(int irq, void *dev)
+{
+ struct loongson2_thermal_data *data = dev;
+
+ /* clear interrupt */
+ writeb(0x3, data->regs + LOONGSON2_TSENSOR_STATUS);
+
+ disable_irq_nosync(irq);
+
+ return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t loongson2_thermal_irq_thread(int irq, void *dev)
+{
+ struct loongson2_thermal_data *data = dev;
+
+ thermal_zone_device_update(data->tzd,
+ THERMAL_EVENT_UNSPECIFIED);
+ enable_irq(data->irq);
+
+ return IRQ_HANDLED;
+}
+
+static int loongson2_thermal_set_trips(void *data, int low, int high)
+{
+ return loongson2_thermal_set(data, low/1000, high/1000, true);
+}
+
+static const struct thermal_zone_of_device_ops loongson2_of_thermal_ops = {
+ .get_temp = loongson2_thermal_get_temp,
+ .set_trips = loongson2_thermal_set_trips,
+};
+
+static int loongson2_thermal_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ struct loongson2_thermal_data *data;
+ int ret;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->pdev = pdev;
+ platform_set_drvdata(pdev, data);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ data->regs = devm_ioremap(dev, res->start, resource_size(res));
+ if (IS_ERR(data->regs))
+ return PTR_ERR(data->regs);
+
+ /* get irq */
+ data->irq = platform_get_irq(pdev, 0);
+ if (data->irq < 0)
+ return data->irq;
+
+ /* get id */
+ if (of_property_read_u32(dev->of_node, "id", &data->id)) {
+ dev_err(dev, "not found id property!\n");
+ data->id = LOONGSON2_SOC_DEFAULT_SENSOR;
+ }
+
+ if (data->id > LOONGSON2_SOC_MAX_SENSOR_NUM - 1) {
+ dev_err(dev, "sensor id error,must be in <0 ~ %d>\n",
+ LOONGSON2_SOC_MAX_SENSOR_NUM - 1);
+ return -EINVAL;
+ }
+
+ writeb(0xff, data->regs + LOONGSON2_TSENSOR_STATUS);
+
+ loongson2_thermal_set(data, 0, 0, false);
+
+ data->tzd = devm_thermal_zone_of_sensor_register(&pdev->dev,
+ data->id, data,
+ &loongson2_of_thermal_ops);
+ if (IS_ERR(data->tzd)) {
+ ret = PTR_ERR(data->tzd);
+ data->tzd = NULL;
+ dev_err(&pdev->dev, "failed to register %d\n", ret);
+ return ret;
+ }
+
+ ret = devm_request_threaded_irq(dev, data->irq,
+ loongson2_thermal_alarm_irq, loongson2_thermal_irq_thread,
+ IRQF_ONESHOT, "loongson2_thermal", data);
+ if (ret < 0) {
+ dev_err(dev, "failed to request alarm irq: %d\n", ret);
+ return ret;
+ }
+
+ /*
+ * Thermal_zone doesn't enable hwmon as default,
+ * enable it here
+ */
+ data->tzd->tzp->no_hwmon = false;
+ ret = thermal_add_hwmon_sysfs(data->tzd);
+ if (ret) {
+ dev_err(dev, "failed to add hwmon sysfs interface %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+int loongson2_thermal_remove(struct platform_device *pdev)
+{
+ struct loongson2_thermal_data *data = platform_get_drvdata(pdev);
+ int reg_off = data->id * 2;
+
+ /* disable interrupt */
+ writew(0, data->regs + LOONGSON2_TSENSOR_CTRL_LO + reg_off);
+ writew(0, data->regs + LOONGSON2_TSENSOR_CTRL_HI + reg_off);
+
+ return 0;
+}
+
+static const struct of_device_id of_loongson2_thermal_match[] = {
+ { .compatible = "loongson,loongson2-thermal",},
+ { /* end */ }
+};
+MODULE_DEVICE_TABLE(of, of_loongson2_thermal_match);
+
+static int __maybe_unused loongson2_thermal_suspend(struct device *dev)
+{
+ struct loongson2_thermal_data *data = dev_get_drvdata(dev);
+ int reg_off = data->id * 2;
+
+ data->ctrl_low_val = readw(data->regs + LOONGSON2_TSENSOR_CTRL_LO + reg_off);
+ data->ctrl_hi_val = readw(data->regs + LOONGSON2_TSENSOR_CTRL_HI + reg_off);
+
+ writew(0, data->regs + LOONGSON2_TSENSOR_CTRL_LO + reg_off);
+ writew(0, data->regs + LOONGSON2_TSENSOR_CTRL_HI + reg_off);
+
+ return 0;
+}
+
+static int __maybe_unused loongson2_thermal_resume(struct device *dev)
+{
+ struct loongson2_thermal_data *data = dev_get_drvdata(dev);
+ int reg_off = data->id * 2;
+
+ writew(data->ctrl_low_val, data->regs + LOONGSON2_TSENSOR_CTRL_LO + reg_off);
+ writew(data->ctrl_hi_val, data->regs + LOONGSON2_TSENSOR_CTRL_HI + reg_off);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(loongson2_thermal_pm_ops,
+ loongson2_thermal_suspend, loongson2_thermal_resume);
+
+static struct platform_driver loongson2_thermal_driver = {
+ .driver = {
+ .name = "loongson2_thermal",
+ .pm = &loongson2_thermal_pm_ops,
+ .of_match_table = of_loongson2_thermal_match,
+ },
+ .probe = loongson2_thermal_probe,
+ .remove = loongson2_thermal_remove,
+};
+module_platform_driver(loongson2_thermal_driver);
--
2.31.1