[PATCH v13 1/2] thermal: loongson-2: add thermal management support

From: Yinbo Zhu
Date: Tue Feb 21 2023 - 04:55:29 EST


This patch adds the support for Loongson-2 thermal sensor controller,
which can support maximum 4 sensors, each sensor contains a sampling
register and a control register. The sampling register is used to obtain
the temperature in real time, the control register GATE field is used to
set the threshold of high or low temperature, when the input temperature
is higher than the high temperature threshold or lower than the low
temperature threshold, an interrupt will occur.

Signed-off-by: zhanghongchen <zhanghongchen@xxxxxxxxxxx>
Signed-off-by: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
---
Change in v13:
1. Add a description about that how works the sensor.
2. Drop the COMPILE_TEST.
3. Rework the help prograph in LOONGSON2_THERMAL Kconfig.
4. Drop the 'tzd' 'irq' and 'pdev' element in loongson2_thermal_data.
5. Drop the reset of variable in loongson2_thermal_set.
6. Drop the function loongson2_thermal_get_sensor_id.
7. Drop the function loongson2_thermal_alarm_irq.
8. Rework the devm_thermal_of_zone_register.
9. Pass 'tzd' instead of 'data' in devm_request_threaded_irq.
10. Drop the "data->tzd->tzp->no_hwmon = false".
11. Drop the loongson2_thermal_remove.
12. Add the sensor id in the of_device_id data field.
13. Drop the save and restore function.
Change in v12:
1. Fixup it about min and max.
2. Use dev_err_probe replace dev_err in devm_request_threaded_irq context.
Change in v11:
1. Add min() and max() to replace related code in function
loongson2_thermal_set.
2. Add dev_err_probe to to replace related code for function
return value use devm_thermal_of_zone_register.
3. Replace thermal_add_hwmon_sysfs with devm_thermal_add_hwmon_sysfs
and use dev_warn replace dev_err in this context.
Change in v10:
1. Add all history change log information.
Change in v9:
1. Switch new API that use devm_thermal_of_zone_register
to replace previous interfaces.
2. Add depend on LOONGARCH || COMPILE_TEST.
Change in v8:
1. Replace string loongson2/Loongson2/LOONGSON2 with loongson-2/
Loongson-2/LOONGSON-2 in Kconfig and commit log and MAINTAINERS
files.
Change in v7:
1. Split the modification of patch 3 and merge it into this patch.
2. Remove the unless code annotation to fix the compile warning
when compile C code with W=1.
Change in v6:
1. NO change, but other patch in this series of patches set has
changes.
Change in v5:
1. NO change, but other patch in this series of patches set has
changes.
Change in v4:
1. Fixup the compatible.
Change in v3:
1. Add a function to gain sensor id an remove dts id.
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.

MAINTAINERS | 7 ++
drivers/thermal/Kconfig | 11 ++
drivers/thermal/Makefile | 1 +
drivers/thermal/loongson2_thermal.c | 167 ++++++++++++++++++++++++++++
4 files changed, 186 insertions(+)
create mode 100644 drivers/thermal/loongson2_thermal.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 57d1d6ecb33d..54e63f51ae6d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12086,6 +12086,13 @@ S: Maintained
F: Documentation/devicetree/bindings/pinctrl/loongson,ls2k-pinctrl.yaml
F: drivers/pinctrl/pinctrl-loongson2.c

+LOONGSON-2 SOC SERIES THERMAL DRIVER
+M: zhanghongchen <zhanghongchen@xxxxxxxxxxx>
+M: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
+L: linux-pm@xxxxxxxxxxxxxxx
+S: Maintained
+F: drivers/thermal/loongson2_thermal.c
+
LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
M: Sathya Prakash <sathya.prakash@xxxxxxxxxxxx>
M: Sreekanth Reddy <sreekanth.reddy@xxxxxxxxxxxx>
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index eaeb2b2ee6e9..d4b5ecead80e 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -508,4 +508,15 @@ 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 "Loongson-2 SoC series thermal driver"
+ depends on LOONGARCH && OF
+ help
+ Support for Thermal driver found on Loongson-2 SoC series platforms.
+ The thermal driver realizes get_temp and set_trips function, which
+ are used to obtain the temperature of the current node and set the
+ temperature range to trigger the interrupt. When the input temperature
+ is higher than the high temperature threshold or lower than the low
+ temperature threshold, the interrupt will occur.
+
endif
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index b9b5dc86f5fd..bfc928f70f6d 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -62,3 +62,4 @@ 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..7d5f32f50c0c
--- /dev/null
+++ b/drivers/thermal/loongson2_thermal.c
@@ -0,0 +1,167 @@
+// 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_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 {
+ int id;
+ void __iomem *regs;
+};
+
+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 = max(low, -40);
+ high = min(high, 125);
+
+ 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 = 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(struct thermal_zone_device *tz, int *temp)
+{
+ u32 reg_val;
+ struct loongson2_thermal_data *data = tz->devdata;
+
+ reg_val = readl(data->regs + LOONGSON2_TSENSOR_OUT);
+ *temp = ((reg_val & 0xff) - 100) * 1000;
+
+ return 0;
+}
+
+static irqreturn_t loongson2_thermal_irq_thread(int irq, void *dev)
+{
+ struct thermal_zone_device *tzd = dev;
+ struct loongson2_thermal_data *data = tzd->devdata;
+
+ /* clear interrupt */
+ writeb(0x3, data->regs + LOONGSON2_TSENSOR_STATUS);
+
+ thermal_zone_device_update(tzd, THERMAL_EVENT_UNSPECIFIED);
+
+ return IRQ_HANDLED;
+}
+
+static int loongson2_thermal_set_trips(struct thermal_zone_device *tz, int low, int high)
+{
+ struct loongson2_thermal_data *data = tz->devdata;
+
+ return loongson2_thermal_set(data, low/1000, high/1000, true);
+}
+
+static const struct thermal_zone_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;
+ struct thermal_zone_device *tzd;
+ int ret, irq, i;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->id = (uintptr_t)device_get_match_data(dev);
+
+ 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 */
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ if (data->id > LOONGSON2_SOC_MAX_SENSOR_NUM - 1 || data->id < 0) {
+ 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);
+
+ for (i = 0; i < LOONGSON2_SOC_MAX_SENSOR_NUM; i++) {
+ tzd = devm_thermal_of_zone_register(&pdev->dev, i,
+ data, &loongson2_of_thermal_ops);
+
+ if (!IS_ERR(tzd))
+ break;
+
+ if (PTR_ERR(tzd) != ENODEV)
+ continue;
+
+ return dev_err_probe(&pdev->dev, PTR_ERR(tzd),
+ "failed to register");
+ }
+
+ ret = devm_request_threaded_irq(dev, irq, NULL, loongson2_thermal_irq_thread,
+ IRQF_ONESHOT, "loongson2_thermal", tzd);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "failed to request alarm irq\n");
+
+ if (devm_thermal_add_hwmon_sysfs(tzd))
+ dev_warn(&pdev->dev, "Failed to add hwmon sysfs attributes\n");
+
+ return 0;
+}
+
+static const struct of_device_id of_loongson2_thermal_match[] = {
+ { .compatible = "loongson,ls2k-thermal", .data = (const void *)0},
+ { /* end */ }
+};
+MODULE_DEVICE_TABLE(of, of_loongson2_thermal_match);
+
+static struct platform_driver loongson2_thermal_driver = {
+ .driver = {
+ .name = "loongson2_thermal",
+ .of_match_table = of_loongson2_thermal_match,
+ },
+ .probe = loongson2_thermal_probe,
+};
+module_platform_driver(loongson2_thermal_driver);
+
+MODULE_DESCRIPTION("Loongson2 thermal driver");
+MODULE_LICENSE("GPL");
--
2.31.1