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
cpu_temp_label(struct device * dev,struct device_attribute * attr,char * buf)58 static ssize_t cpu_temp_label(struct device *dev,
59 struct device_attribute *attr, char *buf)
60 {
61 int id = (to_sensor_dev_attr(attr))->index - 1;
62
63 return sprintf(buf, "CPU %d Temperature\n", id);
64 }
65
get_cpu_temp(struct device * dev,struct device_attribute * attr,char * buf)66 static ssize_t get_cpu_temp(struct device *dev,
67 struct device_attribute *attr, char *buf)
68 {
69 int id = (to_sensor_dev_attr(attr))->index - 1;
70 int value = loongson3_cpu_temp(id);
71
72 return sprintf(buf, "%d\n", value);
73 }
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 struct attribute *cpu_hwmon_attributes[] = {
85 &sensor_dev_attr_temp1_input.dev_attr.attr,
86 &sensor_dev_attr_temp1_label.dev_attr.attr,
87 &sensor_dev_attr_temp2_input.dev_attr.attr,
88 &sensor_dev_attr_temp2_label.dev_attr.attr,
89 &sensor_dev_attr_temp3_input.dev_attr.attr,
90 &sensor_dev_attr_temp3_label.dev_attr.attr,
91 &sensor_dev_attr_temp4_input.dev_attr.attr,
92 &sensor_dev_attr_temp4_label.dev_attr.attr,
93 NULL
94 };
95
cpu_hwmon_is_visible(struct kobject * kobj,struct attribute * attr,int i)96 static umode_t cpu_hwmon_is_visible(struct kobject *kobj,
97 struct attribute *attr, int i)
98 {
99 int id = i / 2;
100
101 if (id < nr_packages)
102 return attr->mode;
103 return 0;
104 }
105
106 static struct attribute_group cpu_hwmon_group = {
107 .attrs = cpu_hwmon_attributes,
108 .is_visible = cpu_hwmon_is_visible,
109 };
110
111 static const struct attribute_group *cpu_hwmon_groups[] = {
112 &cpu_hwmon_group,
113 NULL
114 };
115
116 #define CPU_THERMAL_THRESHOLD 90000
117 static struct delayed_work thermal_work;
118
do_thermal_timer(struct work_struct * work)119 static void do_thermal_timer(struct work_struct *work)
120 {
121 int i, value;
122
123 for (i = 0; i < nr_packages; i++) {
124 value = loongson3_cpu_temp(i);
125 if (value > CPU_THERMAL_THRESHOLD) {
126 pr_emerg("Power off due to high temp: %d\n", value);
127 orderly_poweroff(true);
128 }
129 }
130
131 schedule_delayed_work(&thermal_work, msecs_to_jiffies(5000));
132 }
133
loongson_hwmon_init(void)134 static int __init loongson_hwmon_init(void)
135 {
136 pr_info("Loongson Hwmon Enter...\n");
137
138 if (cpu_has_csr())
139 csr_temp_enable = csr_readl(LOONGSON_CSR_FEATURES) &
140 LOONGSON_CSRF_TEMP;
141
142 nr_packages = loongson_sysconf.nr_cpus /
143 loongson_sysconf.cores_per_package;
144
145 cpu_hwmon_dev = hwmon_device_register_with_groups(NULL, "cpu_hwmon",
146 NULL, cpu_hwmon_groups);
147 if (IS_ERR(cpu_hwmon_dev)) {
148 pr_err("hwmon_device_register fail!\n");
149 return PTR_ERR(cpu_hwmon_dev);
150 }
151
152 INIT_DEFERRABLE_WORK(&thermal_work, do_thermal_timer);
153 schedule_delayed_work(&thermal_work, msecs_to_jiffies(20000));
154
155 return 0;
156 }
157
loongson_hwmon_exit(void)158 static void __exit loongson_hwmon_exit(void)
159 {
160 cancel_delayed_work_sync(&thermal_work);
161 hwmon_device_unregister(cpu_hwmon_dev);
162 }
163
164 module_init(loongson_hwmon_init);
165 module_exit(loongson_hwmon_exit);
166
167 MODULE_AUTHOR("Yu Xiang <xiangy@lemote.com>");
168 MODULE_AUTHOR("Huacai Chen <chenhc@lemote.com>");
169 MODULE_DESCRIPTION("Loongson CPU Hwmon driver");
170 MODULE_LICENSE("GPL");
171