1// SPDX-License-Identifier: GPL-2.0-only
  2#include <linux/err.h>
  3#include <linux/module.h>
  4#include <linux/reboot.h>
  5#include <linux/jiffies.h>
  6#include <linux/hwmon.h>
  7#include <linux/hwmon-sysfs.h>
  8
  9#include <loongson.h>
 10#include <boot_param.h>
 11#include <loongson_hwmon.h>
 12
 13/*
 14 * Loongson-3 series cpu has two sensors inside,
 15 * each of them from 0 to 255,
 16 * if more than 127, that is dangerous.
 17 * here only provide sensor1 data, because it always hot than sensor0
 18 */
 19int loongson3_cpu_temp(int cpu)
 20{
 21	u32 reg, prid_rev;
 22
 23	reg = LOONGSON_CHIPTEMP(cpu);
 24	prid_rev = read_c0_prid() & PRID_REV_MASK;
 25	switch (prid_rev) {
 26	case PRID_REV_LOONGSON3A_R1:
 27		reg = (reg >> 8) & 0xff;
 28		break;
 29	case PRID_REV_LOONGSON3B_R1:
 30	case PRID_REV_LOONGSON3B_R2:
 31	case PRID_REV_LOONGSON3A_R2_0:
 32	case PRID_REV_LOONGSON3A_R2_1:
 33		reg = ((reg >> 8) & 0xff) - 100;
 34		break;
 35	case PRID_REV_LOONGSON3A_R3_0:
 36	case PRID_REV_LOONGSON3A_R3_1:
 37		reg = (reg & 0xffff)*731/0x4000 - 273;
 38		break;
 39	}
 40	return (int)reg * 1000;
 41}
 42
 43static int nr_packages;
 44static struct device *cpu_hwmon_dev;
 45
 46static ssize_t get_hwmon_name(struct device *dev,
 47			struct device_attribute *attr, char *buf);
 48static SENSOR_DEVICE_ATTR(name, S_IRUGO, get_hwmon_name, NULL, 0);
 49
 50static struct attribute *cpu_hwmon_attributes[] = {
 51	&sensor_dev_attr_name.dev_attr.attr,
 52	NULL
 53};
 54
 55/* Hwmon device attribute group */
 56static struct attribute_group cpu_hwmon_attribute_group = {
 57	.attrs = cpu_hwmon_attributes,
 58};
 59
 60/* Hwmon device get name */
 61static ssize_t get_hwmon_name(struct device *dev,
 62			struct device_attribute *attr, char *buf)
 63{
 64	return sprintf(buf, "cpu-hwmon\n");
 65}
 66
 67static ssize_t get_cpu_temp(struct device *dev,
 68			struct device_attribute *attr, char *buf);
 69static ssize_t cpu_temp_label(struct device *dev,
 70			struct device_attribute *attr, char *buf);
 71
 72static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, get_cpu_temp, NULL, 1);
 73static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, cpu_temp_label, NULL, 1);
 74static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, get_cpu_temp, NULL, 2);
 75static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, cpu_temp_label, NULL, 2);
 76static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, get_cpu_temp, NULL, 3);
 77static SENSOR_DEVICE_ATTR(temp3_label, S_IRUGO, cpu_temp_label, NULL, 3);
 78static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, get_cpu_temp, NULL, 4);
 79static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, cpu_temp_label, NULL, 4);
 80
 81static const struct attribute *hwmon_cputemp[4][3] = {
 82	{
 83		&sensor_dev_attr_temp1_input.dev_attr.attr,
 84		&sensor_dev_attr_temp1_label.dev_attr.attr,
 85		NULL
 86	},
 87	{
 88		&sensor_dev_attr_temp2_input.dev_attr.attr,
 89		&sensor_dev_attr_temp2_label.dev_attr.attr,
 90		NULL
 91	},
 92	{
 93		&sensor_dev_attr_temp3_input.dev_attr.attr,
 94		&sensor_dev_attr_temp3_label.dev_attr.attr,
 95		NULL
 96	},
 97	{
 98		&sensor_dev_attr_temp4_input.dev_attr.attr,
 99		&sensor_dev_attr_temp4_label.dev_attr.attr,
100		NULL
101	}
102};
103
104static ssize_t cpu_temp_label(struct device *dev,
105			struct device_attribute *attr, char *buf)
106{
107	int id = (to_sensor_dev_attr(attr))->index - 1;
108	return sprintf(buf, "CPU %d Temperature\n", id);
109}
110
111static ssize_t get_cpu_temp(struct device *dev,
112			struct device_attribute *attr, char *buf)
113{
114	int id = (to_sensor_dev_attr(attr))->index - 1;
115	int value = loongson3_cpu_temp(id);
116	return sprintf(buf, "%d\n", value);
117}
118
119static int create_sysfs_cputemp_files(struct kobject *kobj)
120{
121	int i, ret = 0;
122
123	for (i=0; i<nr_packages; i++)
124		ret = sysfs_create_files(kobj, hwmon_cputemp[i]);
125
126	return ret;
127}
128
129static void remove_sysfs_cputemp_files(struct kobject *kobj)
130{
131	int i;
132
133	for (i=0; i<nr_packages; i++)
134		sysfs_remove_files(kobj, hwmon_cputemp[i]);
135}
136
137#define CPU_THERMAL_THRESHOLD 90000
138static struct delayed_work thermal_work;
139
140static void do_thermal_timer(struct work_struct *work)
141{
142	int i, value, temp_max = 0;
143
144	for (i=0; i<nr_packages; i++) {
145		value = loongson3_cpu_temp(i);
146		if (value > temp_max)
147			temp_max = value;
148	}
149
150	if (temp_max <= CPU_THERMAL_THRESHOLD)
151		schedule_delayed_work(&thermal_work, msecs_to_jiffies(5000));
152	else
153		orderly_poweroff(true);
154}
155
156static int __init loongson_hwmon_init(void)
157{
158	int ret;
159
160	pr_info("Loongson Hwmon Enter...\n");
161
162	cpu_hwmon_dev = hwmon_device_register(NULL);
163	if (IS_ERR(cpu_hwmon_dev)) {
164		ret = -ENOMEM;
165		pr_err("hwmon_device_register fail!\n");
166		goto fail_hwmon_device_register;
167	}
168
169	nr_packages = loongson_sysconf.nr_cpus /
170		loongson_sysconf.cores_per_package;
171
172	ret = sysfs_create_group(&cpu_hwmon_dev->kobj,
173				&cpu_hwmon_attribute_group);
174	if (ret) {
175		pr_err("fail to create loongson hwmon!\n");
176		goto fail_sysfs_create_group_hwmon;
177	}
178
179	ret = create_sysfs_cputemp_files(&cpu_hwmon_dev->kobj);
180	if (ret) {
181		pr_err("fail to create cpu temperature interface!\n");
182		goto fail_create_sysfs_cputemp_files;
183	}
184
185	INIT_DEFERRABLE_WORK(&thermal_work, do_thermal_timer);
186	schedule_delayed_work(&thermal_work, msecs_to_jiffies(20000));
187
188	return ret;
189
190fail_create_sysfs_cputemp_files:
191	sysfs_remove_group(&cpu_hwmon_dev->kobj,
192				&cpu_hwmon_attribute_group);
193
194fail_sysfs_create_group_hwmon:
195	hwmon_device_unregister(cpu_hwmon_dev);
196
197fail_hwmon_device_register:
198	return ret;
199}
200
201static void __exit loongson_hwmon_exit(void)
202{
203	cancel_delayed_work_sync(&thermal_work);
204	remove_sysfs_cputemp_files(&cpu_hwmon_dev->kobj);
205	sysfs_remove_group(&cpu_hwmon_dev->kobj,
206				&cpu_hwmon_attribute_group);
207	hwmon_device_unregister(cpu_hwmon_dev);
208}
209
210module_init(loongson_hwmon_init);
211module_exit(loongson_hwmon_exit);
212
213MODULE_AUTHOR("Yu Xiang <xiangy@lemote.com>");
214MODULE_AUTHOR("Huacai Chen <chenhc@lemote.com>");
215MODULE_DESCRIPTION("Loongson CPU Hwmon driver");
216MODULE_LICENSE("GPL");