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path: root/drivers/platform/mips/cpu_hwmon.c
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Diffstat (limited to 'drivers/platform/mips/cpu_hwmon.c')
-rw-r--r--drivers/platform/mips/cpu_hwmon.c214
1 files changed, 214 insertions, 0 deletions
diff --git a/drivers/platform/mips/cpu_hwmon.c b/drivers/platform/mips/cpu_hwmon.c
new file mode 100644
index 000000000..98128374d
--- /dev/null
+++ b/drivers/platform/mips/cpu_hwmon.c
@@ -0,0 +1,214 @@
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/reboot.h>
+#include <linux/jiffies.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+#include <loongson.h>
+#include <boot_param.h>
+#include <loongson_hwmon.h>
+
+/*
+ * Loongson-3 series cpu has two sensors inside,
+ * each of them from 0 to 255,
+ * if more than 127, that is dangerous.
+ * here only provide sensor1 data, because it always hot than sensor0
+ */
+int loongson3_cpu_temp(int cpu)
+{
+ u32 reg, prid_rev;
+
+ reg = LOONGSON_CHIPTEMP(cpu);
+ prid_rev = read_c0_prid() & PRID_REV_MASK;
+ switch (prid_rev) {
+ case PRID_REV_LOONGSON3A_R1:
+ reg = (reg >> 8) & 0xff;
+ break;
+ case PRID_REV_LOONGSON3A_R2:
+ case PRID_REV_LOONGSON3B_R1:
+ case PRID_REV_LOONGSON3B_R2:
+ reg = ((reg >> 8) & 0xff) - 100;
+ break;
+ case PRID_REV_LOONGSON3A_R3_0:
+ case PRID_REV_LOONGSON3A_R3_1:
+ reg = (reg & 0xffff)*731/0x4000 - 273;
+ break;
+ }
+ return (int)reg * 1000;
+}
+
+static int nr_packages;
+static struct device *cpu_hwmon_dev;
+
+static ssize_t get_hwmon_name(struct device *dev,
+ struct device_attribute *attr, char *buf);
+static SENSOR_DEVICE_ATTR(name, S_IRUGO, get_hwmon_name, NULL, 0);
+
+static struct attribute *cpu_hwmon_attributes[] = {
+ &sensor_dev_attr_name.dev_attr.attr,
+ NULL
+};
+
+/* Hwmon device attribute group */
+static struct attribute_group cpu_hwmon_attribute_group = {
+ .attrs = cpu_hwmon_attributes,
+};
+
+/* Hwmon device get name */
+static ssize_t get_hwmon_name(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "cpu-hwmon\n");
+}
+
+static ssize_t get_cpu_temp(struct device *dev,
+ struct device_attribute *attr, char *buf);
+static ssize_t cpu_temp_label(struct device *dev,
+ struct device_attribute *attr, char *buf);
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, get_cpu_temp, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, cpu_temp_label, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, get_cpu_temp, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, cpu_temp_label, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, get_cpu_temp, NULL, 3);
+static SENSOR_DEVICE_ATTR(temp3_label, S_IRUGO, cpu_temp_label, NULL, 3);
+static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, get_cpu_temp, NULL, 4);
+static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, cpu_temp_label, NULL, 4);
+
+static const struct attribute *hwmon_cputemp[4][3] = {
+ {
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_temp1_label.dev_attr.attr,
+ NULL
+ },
+ {
+ &sensor_dev_attr_temp2_input.dev_attr.attr,
+ &sensor_dev_attr_temp2_label.dev_attr.attr,
+ NULL
+ },
+ {
+ &sensor_dev_attr_temp3_input.dev_attr.attr,
+ &sensor_dev_attr_temp3_label.dev_attr.attr,
+ NULL
+ },
+ {
+ &sensor_dev_attr_temp4_input.dev_attr.attr,
+ &sensor_dev_attr_temp4_label.dev_attr.attr,
+ NULL
+ }
+};
+
+static ssize_t cpu_temp_label(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int id = (to_sensor_dev_attr(attr))->index - 1;
+ return sprintf(buf, "CPU %d Temperature\n", id);
+}
+
+static ssize_t get_cpu_temp(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int id = (to_sensor_dev_attr(attr))->index - 1;
+ int value = loongson3_cpu_temp(id);
+ return sprintf(buf, "%d\n", value);
+}
+
+static int create_sysfs_cputemp_files(struct kobject *kobj)
+{
+ int i, ret = 0;
+
+ for (i=0; i<nr_packages; i++)
+ ret = sysfs_create_files(kobj, hwmon_cputemp[i]);
+
+ return ret;
+}
+
+static void remove_sysfs_cputemp_files(struct kobject *kobj)
+{
+ int i;
+
+ for (i=0; i<nr_packages; i++)
+ sysfs_remove_files(kobj, hwmon_cputemp[i]);
+}
+
+#define CPU_THERMAL_THRESHOLD 90000
+static struct delayed_work thermal_work;
+
+static void do_thermal_timer(struct work_struct *work)
+{
+ int i, value, temp_max = 0;
+
+ for (i=0; i<nr_packages; i++) {
+ value = loongson3_cpu_temp(i);
+ if (value > temp_max)
+ temp_max = value;
+ }
+
+ if (temp_max <= CPU_THERMAL_THRESHOLD)
+ schedule_delayed_work(&thermal_work, msecs_to_jiffies(5000));
+ else
+ orderly_poweroff(true);
+}
+
+static int __init loongson_hwmon_init(void)
+{
+ int ret;
+
+ pr_info("Loongson Hwmon Enter...\n");
+
+ cpu_hwmon_dev = hwmon_device_register(NULL);
+ if (IS_ERR(cpu_hwmon_dev)) {
+ ret = PTR_ERR(cpu_hwmon_dev);
+ pr_err("hwmon_device_register fail!\n");
+ goto fail_hwmon_device_register;
+ }
+
+ nr_packages = loongson_sysconf.nr_cpus /
+ loongson_sysconf.cores_per_package;
+
+ ret = sysfs_create_group(&cpu_hwmon_dev->kobj,
+ &cpu_hwmon_attribute_group);
+ if (ret) {
+ pr_err("fail to create loongson hwmon!\n");
+ goto fail_sysfs_create_group_hwmon;
+ }
+
+ ret = create_sysfs_cputemp_files(&cpu_hwmon_dev->kobj);
+ if (ret) {
+ pr_err("fail to create cpu temperature interface!\n");
+ goto fail_create_sysfs_cputemp_files;
+ }
+
+ INIT_DEFERRABLE_WORK(&thermal_work, do_thermal_timer);
+ schedule_delayed_work(&thermal_work, msecs_to_jiffies(20000));
+
+ return ret;
+
+fail_create_sysfs_cputemp_files:
+ sysfs_remove_group(&cpu_hwmon_dev->kobj,
+ &cpu_hwmon_attribute_group);
+
+fail_sysfs_create_group_hwmon:
+ hwmon_device_unregister(cpu_hwmon_dev);
+
+fail_hwmon_device_register:
+ return ret;
+}
+
+static void __exit loongson_hwmon_exit(void)
+{
+ cancel_delayed_work_sync(&thermal_work);
+ remove_sysfs_cputemp_files(&cpu_hwmon_dev->kobj);
+ sysfs_remove_group(&cpu_hwmon_dev->kobj,
+ &cpu_hwmon_attribute_group);
+ hwmon_device_unregister(cpu_hwmon_dev);
+}
+
+module_init(loongson_hwmon_init);
+module_exit(loongson_hwmon_exit);
+
+MODULE_AUTHOR("Yu Xiang <xiangy@lemote.com>");
+MODULE_AUTHOR("Huacai Chen <chenhc@lemote.com>");
+MODULE_DESCRIPTION("Loongson CPU Hwmon driver");
+MODULE_LICENSE("GPL");