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
14static 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 */
22int 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
51out:
52	return (int)reg * 1000;
53}
54
55static int nr_packages;
56static struct device *cpu_hwmon_dev;
57
58static 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
66static 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
75static SENSOR_DEVICE_ATTR(temp1_input, 0444, get_cpu_temp, NULL, 1);
76static SENSOR_DEVICE_ATTR(temp1_label, 0444, cpu_temp_label, NULL, 1);
77static SENSOR_DEVICE_ATTR(temp2_input, 0444, get_cpu_temp, NULL, 2);
78static SENSOR_DEVICE_ATTR(temp2_label, 0444, cpu_temp_label, NULL, 2);
79static SENSOR_DEVICE_ATTR(temp3_input, 0444, get_cpu_temp, NULL, 3);
80static SENSOR_DEVICE_ATTR(temp3_label, 0444, cpu_temp_label, NULL, 3);
81static SENSOR_DEVICE_ATTR(temp4_input, 0444, get_cpu_temp, NULL, 4);
82static SENSOR_DEVICE_ATTR(temp4_label, 0444, cpu_temp_label, NULL, 4);
83
84static 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
96static 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
106static struct attribute_group cpu_hwmon_group = {
107	.attrs = cpu_hwmon_attributes,
108	.is_visible = cpu_hwmon_is_visible,
109};
110
111static const struct attribute_group *cpu_hwmon_groups[] = {
112	&cpu_hwmon_group,
113	NULL
114};
115
116#define CPU_THERMAL_THRESHOLD 90000
117static struct delayed_work thermal_work;
118
119static 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
134static 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
158static void __exit loongson_hwmon_exit(void)
159{
160	cancel_delayed_work_sync(&thermal_work);
161	hwmon_device_unregister(cpu_hwmon_dev);
162}
163
164module_init(loongson_hwmon_init);
165module_exit(loongson_hwmon_exit);
166
167MODULE_AUTHOR("Yu Xiang <xiangy@lemote.com>");
168MODULE_AUTHOR("Huacai Chen <chenhc@lemote.com>");
169MODULE_DESCRIPTION("Loongson CPU Hwmon driver");
170MODULE_LICENSE("GPL");
171