1 #include <linux/err.h>
2 #include <linux/module.h>
3 #include <linux/reboot.h>
4 #include <linux/jiffies.h>
5 #include <linux/hwmon.h>
6 #include <linux/hwmon-sysfs.h>
7
8 #include <loongson.h>
9 #include <boot_param.h>
10 #include <loongson_hwmon.h>
11
12 /*
13 * Loongson-3 series cpu has two sensors inside,
14 * each of them from 0 to 255,
15 * if more than 127, that is dangerous.
16 * here only provide sensor1 data, because it always hot than sensor0
17 */
loongson3_cpu_temp(int cpu)18 int loongson3_cpu_temp(int cpu)
19 {
20 u32 reg, prid_rev;
21
22 reg = LOONGSON_CHIPTEMP(cpu);
23 prid_rev = read_c0_prid() & PRID_REV_MASK;
24 switch (prid_rev) {
25 case PRID_REV_LOONGSON3A_R1:
26 reg = (reg >> 8) & 0xff;
27 break;
28 case PRID_REV_LOONGSON3A_R2:
29 case PRID_REV_LOONGSON3B_R1:
30 case PRID_REV_LOONGSON3B_R2:
31 reg = ((reg >> 8) & 0xff) - 100;
32 break;
33 case PRID_REV_LOONGSON3A_R3_0:
34 case PRID_REV_LOONGSON3A_R3_1:
35 reg = (reg & 0xffff)*731/0x4000 - 273;
36 break;
37 }
38 return (int)reg * 1000;
39 }
40
41 static int nr_packages;
42 static struct device *cpu_hwmon_dev;
43
44 static ssize_t get_hwmon_name(struct device *dev,
45 struct device_attribute *attr, char *buf);
46 static SENSOR_DEVICE_ATTR(name, S_IRUGO, get_hwmon_name, NULL, 0);
47
48 static struct attribute *cpu_hwmon_attributes[] = {
49 &sensor_dev_attr_name.dev_attr.attr,
50 NULL
51 };
52
53 /* Hwmon device attribute group */
54 static struct attribute_group cpu_hwmon_attribute_group = {
55 .attrs = cpu_hwmon_attributes,
56 };
57
58 /* Hwmon device get name */
get_hwmon_name(struct device * dev,struct device_attribute * attr,char * buf)59 static ssize_t get_hwmon_name(struct device *dev,
60 struct device_attribute *attr, char *buf)
61 {
62 return sprintf(buf, "cpu-hwmon\n");
63 }
64
65 static ssize_t get_cpu_temp(struct device *dev,
66 struct device_attribute *attr, char *buf);
67 static ssize_t cpu_temp_label(struct device *dev,
68 struct device_attribute *attr, char *buf);
69
70 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, get_cpu_temp, NULL, 1);
71 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, cpu_temp_label, NULL, 1);
72 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, get_cpu_temp, NULL, 2);
73 static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, cpu_temp_label, NULL, 2);
74 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, get_cpu_temp, NULL, 3);
75 static SENSOR_DEVICE_ATTR(temp3_label, S_IRUGO, cpu_temp_label, NULL, 3);
76 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, get_cpu_temp, NULL, 4);
77 static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, cpu_temp_label, NULL, 4);
78
79 static const struct attribute *hwmon_cputemp[4][3] = {
80 {
81 &sensor_dev_attr_temp1_input.dev_attr.attr,
82 &sensor_dev_attr_temp1_label.dev_attr.attr,
83 NULL
84 },
85 {
86 &sensor_dev_attr_temp2_input.dev_attr.attr,
87 &sensor_dev_attr_temp2_label.dev_attr.attr,
88 NULL
89 },
90 {
91 &sensor_dev_attr_temp3_input.dev_attr.attr,
92 &sensor_dev_attr_temp3_label.dev_attr.attr,
93 NULL
94 },
95 {
96 &sensor_dev_attr_temp4_input.dev_attr.attr,
97 &sensor_dev_attr_temp4_label.dev_attr.attr,
98 NULL
99 }
100 };
101
cpu_temp_label(struct device * dev,struct device_attribute * attr,char * buf)102 static ssize_t cpu_temp_label(struct device *dev,
103 struct device_attribute *attr, char *buf)
104 {
105 int id = (to_sensor_dev_attr(attr))->index - 1;
106 return sprintf(buf, "CPU %d Temperature\n", id);
107 }
108
get_cpu_temp(struct device * dev,struct device_attribute * attr,char * buf)109 static ssize_t get_cpu_temp(struct device *dev,
110 struct device_attribute *attr, char *buf)
111 {
112 int id = (to_sensor_dev_attr(attr))->index - 1;
113 int value = loongson3_cpu_temp(id);
114 return sprintf(buf, "%d\n", value);
115 }
116
create_sysfs_cputemp_files(struct kobject * kobj)117 static int create_sysfs_cputemp_files(struct kobject *kobj)
118 {
119 int i, ret = 0;
120
121 for (i=0; i<nr_packages; i++)
122 ret = sysfs_create_files(kobj, hwmon_cputemp[i]);
123
124 return ret;
125 }
126
remove_sysfs_cputemp_files(struct kobject * kobj)127 static void remove_sysfs_cputemp_files(struct kobject *kobj)
128 {
129 int i;
130
131 for (i=0; i<nr_packages; i++)
132 sysfs_remove_files(kobj, hwmon_cputemp[i]);
133 }
134
135 #define CPU_THERMAL_THRESHOLD 90000
136 static struct delayed_work thermal_work;
137
do_thermal_timer(struct work_struct * work)138 static void do_thermal_timer(struct work_struct *work)
139 {
140 int i, value, temp_max = 0;
141
142 for (i=0; i<nr_packages; i++) {
143 value = loongson3_cpu_temp(i);
144 if (value > temp_max)
145 temp_max = value;
146 }
147
148 if (temp_max <= CPU_THERMAL_THRESHOLD)
149 schedule_delayed_work(&thermal_work, msecs_to_jiffies(5000));
150 else
151 orderly_poweroff(true);
152 }
153
loongson_hwmon_init(void)154 static int __init loongson_hwmon_init(void)
155 {
156 int ret;
157
158 pr_info("Loongson Hwmon Enter...\n");
159
160 cpu_hwmon_dev = hwmon_device_register(NULL);
161 if (IS_ERR(cpu_hwmon_dev)) {
162 ret = -ENOMEM;
163 pr_err("hwmon_device_register fail!\n");
164 goto fail_hwmon_device_register;
165 }
166
167 nr_packages = loongson_sysconf.nr_cpus /
168 loongson_sysconf.cores_per_package;
169
170 ret = sysfs_create_group(&cpu_hwmon_dev->kobj,
171 &cpu_hwmon_attribute_group);
172 if (ret) {
173 pr_err("fail to create loongson hwmon!\n");
174 goto fail_sysfs_create_group_hwmon;
175 }
176
177 ret = create_sysfs_cputemp_files(&cpu_hwmon_dev->kobj);
178 if (ret) {
179 pr_err("fail to create cpu temperature interface!\n");
180 goto fail_create_sysfs_cputemp_files;
181 }
182
183 INIT_DEFERRABLE_WORK(&thermal_work, do_thermal_timer);
184 schedule_delayed_work(&thermal_work, msecs_to_jiffies(20000));
185
186 return ret;
187
188 fail_create_sysfs_cputemp_files:
189 sysfs_remove_group(&cpu_hwmon_dev->kobj,
190 &cpu_hwmon_attribute_group);
191
192 fail_sysfs_create_group_hwmon:
193 hwmon_device_unregister(cpu_hwmon_dev);
194
195 fail_hwmon_device_register:
196 return ret;
197 }
198
loongson_hwmon_exit(void)199 static void __exit loongson_hwmon_exit(void)
200 {
201 cancel_delayed_work_sync(&thermal_work);
202 remove_sysfs_cputemp_files(&cpu_hwmon_dev->kobj);
203 sysfs_remove_group(&cpu_hwmon_dev->kobj,
204 &cpu_hwmon_attribute_group);
205 hwmon_device_unregister(cpu_hwmon_dev);
206 }
207
208 module_init(loongson_hwmon_init);
209 module_exit(loongson_hwmon_exit);
210
211 MODULE_AUTHOR("Yu Xiang <xiangy@lemote.com>");
212 MODULE_AUTHOR("Huacai Chen <chenhc@lemote.com>");
213 MODULE_DESCRIPTION("Loongson CPU Hwmon driver");
214 MODULE_LICENSE("GPL");
215
