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