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 #include <loongson_regs.h>
13
14 static int csr_temp_enable;
15
16 /*
17 * Loongson-3 series cpu has two sensors inside,
18 * each of them from 0 to 255,
19 * if more than 127, that is dangerous.
20 * here only provide sensor1 data, because it always hot than sensor0
21 */
loongson3_cpu_temp(int cpu)22 int loongson3_cpu_temp(int cpu)
23 {
24 u32 reg, prid_rev;
25
26 if (csr_temp_enable) {
27 reg = (csr_readl(LOONGSON_CSR_CPUTEMP) & 0xff);
28 goto out;
29 }
30
31 reg = LOONGSON_CHIPTEMP(cpu);
32 prid_rev = read_c0_prid() & PRID_REV_MASK;
33
34 switch (prid_rev) {
35 case PRID_REV_LOONGSON3A_R1:
36 reg = (reg >> 8) & 0xff;
37 break;
38 case PRID_REV_LOONGSON3B_R1:
39 case PRID_REV_LOONGSON3B_R2:
40 case PRID_REV_LOONGSON3A_R2_0:
41 case PRID_REV_LOONGSON3A_R2_1:
42 reg = ((reg >> 8) & 0xff) - 100;
43 break;
44 case PRID_REV_LOONGSON3A_R3_0:
45 case PRID_REV_LOONGSON3A_R3_1:
46 default:
47 reg = (reg & 0xffff) * 731 / 0x4000 - 273;
48 break;
49 }
50
51 out:
52 return (int)reg * 1000;
53 }
54
55 static int nr_packages;
56 static struct device *cpu_hwmon_dev;
57
58 static SENSOR_DEVICE_ATTR(name, 0444, NULL, NULL, 0);
59
60 static struct attribute *cpu_hwmon_attributes[] = {
61 &sensor_dev_attr_name.dev_attr.attr,
62 NULL
63 };
64
65 /* Hwmon device attribute group */
66 static struct attribute_group cpu_hwmon_attribute_group = {
67 .attrs = cpu_hwmon_attributes,
68 };
69
70 static ssize_t get_cpu_temp(struct device *dev,
71 struct device_attribute *attr, char *buf);
72 static ssize_t cpu_temp_label(struct device *dev,
73 struct device_attribute *attr, char *buf);
74
75 static SENSOR_DEVICE_ATTR(temp1_input, 0444, get_cpu_temp, NULL, 1);
76 static SENSOR_DEVICE_ATTR(temp1_label, 0444, cpu_temp_label, NULL, 1);
77 static SENSOR_DEVICE_ATTR(temp2_input, 0444, get_cpu_temp, NULL, 2);
78 static SENSOR_DEVICE_ATTR(temp2_label, 0444, cpu_temp_label, NULL, 2);
79 static SENSOR_DEVICE_ATTR(temp3_input, 0444, get_cpu_temp, NULL, 3);
80 static SENSOR_DEVICE_ATTR(temp3_label, 0444, cpu_temp_label, NULL, 3);
81 static SENSOR_DEVICE_ATTR(temp4_input, 0444, get_cpu_temp, NULL, 4);
82 static SENSOR_DEVICE_ATTR(temp4_label, 0444, cpu_temp_label, NULL, 4);
83
84 static const struct attribute *hwmon_cputemp[4][3] = {
85 {
86 &sensor_dev_attr_temp1_input.dev_attr.attr,
87 &sensor_dev_attr_temp1_label.dev_attr.attr,
88 NULL
89 },
90 {
91 &sensor_dev_attr_temp2_input.dev_attr.attr,
92 &sensor_dev_attr_temp2_label.dev_attr.attr,
93 NULL
94 },
95 {
96 &sensor_dev_attr_temp3_input.dev_attr.attr,
97 &sensor_dev_attr_temp3_label.dev_attr.attr,
98 NULL
99 },
100 {
101 &sensor_dev_attr_temp4_input.dev_attr.attr,
102 &sensor_dev_attr_temp4_label.dev_attr.attr,
103 NULL
104 }
105 };
106
cpu_temp_label(struct device * dev,struct device_attribute * attr,char * buf)107 static ssize_t cpu_temp_label(struct device *dev,
108 struct device_attribute *attr, char *buf)
109 {
110 int id = (to_sensor_dev_attr(attr))->index - 1;
111
112 return sprintf(buf, "CPU %d Temperature\n", id);
113 }
114
get_cpu_temp(struct device * dev,struct device_attribute * attr,char * buf)115 static ssize_t get_cpu_temp(struct device *dev,
116 struct device_attribute *attr, char *buf)
117 {
118 int id = (to_sensor_dev_attr(attr))->index - 1;
119 int value = loongson3_cpu_temp(id);
120
121 return sprintf(buf, "%d\n", value);
122 }
123
create_sysfs_cputemp_files(struct kobject * kobj)124 static int create_sysfs_cputemp_files(struct kobject *kobj)
125 {
126 int i, ret = 0;
127
128 for (i = 0; i < nr_packages; i++)
129 ret = sysfs_create_files(kobj, hwmon_cputemp[i]);
130
131 return ret;
132 }
133
remove_sysfs_cputemp_files(struct kobject * kobj)134 static void remove_sysfs_cputemp_files(struct kobject *kobj)
135 {
136 int i;
137
138 for (i = 0; i < nr_packages; i++)
139 sysfs_remove_files(kobj, hwmon_cputemp[i]);
140 }
141
142 #define CPU_THERMAL_THRESHOLD 90000
143 static struct delayed_work thermal_work;
144
do_thermal_timer(struct work_struct * work)145 static void do_thermal_timer(struct work_struct *work)
146 {
147 int i, value;
148
149 for (i = 0; i < nr_packages; i++) {
150 value = loongson3_cpu_temp(i);
151 if (value > CPU_THERMAL_THRESHOLD) {
152 pr_emerg("Power off due to high temp: %d\n", value);
153 orderly_poweroff(true);
154 }
155 }
156
157 schedule_delayed_work(&thermal_work, msecs_to_jiffies(5000));
158 }
159
loongson_hwmon_init(void)160 static int __init loongson_hwmon_init(void)
161 {
162 int ret;
163
164 pr_info("Loongson Hwmon Enter...\n");
165
166 if (cpu_has_csr())
167 csr_temp_enable = csr_readl(LOONGSON_CSR_FEATURES) &
168 LOONGSON_CSRF_TEMP;
169
170 cpu_hwmon_dev = hwmon_device_register_with_info(NULL, "cpu_hwmon", NULL, NULL, NULL);
171 if (IS_ERR(cpu_hwmon_dev)) {
172 ret = PTR_ERR(cpu_hwmon_dev);
173 pr_err("hwmon_device_register fail!\n");
174 goto fail_hwmon_device_register;
175 }
176
177 nr_packages = loongson_sysconf.nr_cpus /
178 loongson_sysconf.cores_per_package;
179
180 ret = create_sysfs_cputemp_files(&cpu_hwmon_dev->kobj);
181 if (ret) {
182 pr_err("fail to create cpu temperature interface!\n");
183 goto fail_create_sysfs_cputemp_files;
184 }
185
186 INIT_DEFERRABLE_WORK(&thermal_work, do_thermal_timer);
187 schedule_delayed_work(&thermal_work, msecs_to_jiffies(20000));
188
189 return ret;
190
191 fail_create_sysfs_cputemp_files:
192 sysfs_remove_group(&cpu_hwmon_dev->kobj,
193 &cpu_hwmon_attribute_group);
194 hwmon_device_unregister(cpu_hwmon_dev);
195
196 fail_hwmon_device_register:
197 return ret;
198 }
199
loongson_hwmon_exit(void)200 static void __exit loongson_hwmon_exit(void)
201 {
202 cancel_delayed_work_sync(&thermal_work);
203 remove_sysfs_cputemp_files(&cpu_hwmon_dev->kobj);
204 sysfs_remove_group(&cpu_hwmon_dev->kobj,
205 &cpu_hwmon_attribute_group);
206 hwmon_device_unregister(cpu_hwmon_dev);
207 }
208
209 module_init(loongson_hwmon_init);
210 module_exit(loongson_hwmon_exit);
211
212 MODULE_AUTHOR("Yu Xiang <xiangy@lemote.com>");
213 MODULE_AUTHOR("Huacai Chen <chenhc@lemote.com>");
214 MODULE_DESCRIPTION("Loongson CPU Hwmon driver");
215 MODULE_LICENSE("GPL");
216
