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 13 /* 14 * Loongson-3 series cpu has two sensors inside, 15 * each of them from 0 to 255, 16 * if more than 127, that is dangerous. 17 * here only provide sensor1 data, because it always hot than sensor0 18 */ 19 int loongson3_cpu_temp(int cpu) 20 { 21 u32 reg, prid_rev; 22 23 reg = LOONGSON_CHIPTEMP(cpu); 24 prid_rev = read_c0_prid() & PRID_REV_MASK; 25 switch (prid_rev) { 26 case PRID_REV_LOONGSON3A_R1: 27 reg = (reg >> 8) & 0xff; 28 break; 29 case PRID_REV_LOONGSON3B_R1: 30 case PRID_REV_LOONGSON3B_R2: 31 case PRID_REV_LOONGSON3A_R2_0: 32 case PRID_REV_LOONGSON3A_R2_1: 33 reg = ((reg >> 8) & 0xff) - 100; 34 break; 35 case PRID_REV_LOONGSON3A_R3_0: 36 case PRID_REV_LOONGSON3A_R3_1: 37 reg = (reg & 0xffff)*731/0x4000 - 273; 38 break; 39 } 40 return (int)reg * 1000; 41 } 42 43 static int nr_packages; 44 static struct device *cpu_hwmon_dev; 45 46 static ssize_t get_hwmon_name(struct device *dev, 47 struct device_attribute *attr, char *buf); 48 static SENSOR_DEVICE_ATTR(name, S_IRUGO, get_hwmon_name, NULL, 0); 49 50 static struct attribute *cpu_hwmon_attributes[] = { 51 &sensor_dev_attr_name.dev_attr.attr, 52 NULL 53 }; 54 55 /* Hwmon device attribute group */ 56 static struct attribute_group cpu_hwmon_attribute_group = { 57 .attrs = cpu_hwmon_attributes, 58 }; 59 60 /* Hwmon device get name */ 61 static ssize_t get_hwmon_name(struct device *dev, 62 struct device_attribute *attr, char *buf) 63 { 64 return sprintf(buf, "cpu-hwmon\n"); 65 } 66 67 static ssize_t get_cpu_temp(struct device *dev, 68 struct device_attribute *attr, char *buf); 69 static ssize_t cpu_temp_label(struct device *dev, 70 struct device_attribute *attr, char *buf); 71 72 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, get_cpu_temp, NULL, 1); 73 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, cpu_temp_label, NULL, 1); 74 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, get_cpu_temp, NULL, 2); 75 static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, cpu_temp_label, NULL, 2); 76 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, get_cpu_temp, NULL, 3); 77 static SENSOR_DEVICE_ATTR(temp3_label, S_IRUGO, cpu_temp_label, NULL, 3); 78 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, get_cpu_temp, NULL, 4); 79 static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, cpu_temp_label, NULL, 4); 80 81 static const struct attribute *hwmon_cputemp[4][3] = { 82 { 83 &sensor_dev_attr_temp1_input.dev_attr.attr, 84 &sensor_dev_attr_temp1_label.dev_attr.attr, 85 NULL 86 }, 87 { 88 &sensor_dev_attr_temp2_input.dev_attr.attr, 89 &sensor_dev_attr_temp2_label.dev_attr.attr, 90 NULL 91 }, 92 { 93 &sensor_dev_attr_temp3_input.dev_attr.attr, 94 &sensor_dev_attr_temp3_label.dev_attr.attr, 95 NULL 96 }, 97 { 98 &sensor_dev_attr_temp4_input.dev_attr.attr, 99 &sensor_dev_attr_temp4_label.dev_attr.attr, 100 NULL 101 } 102 }; 103 104 static ssize_t cpu_temp_label(struct device *dev, 105 struct device_attribute *attr, char *buf) 106 { 107 int id = (to_sensor_dev_attr(attr))->index - 1; 108 return sprintf(buf, "CPU %d Temperature\n", id); 109 } 110 111 static ssize_t get_cpu_temp(struct device *dev, 112 struct device_attribute *attr, char *buf) 113 { 114 int id = (to_sensor_dev_attr(attr))->index - 1; 115 int value = loongson3_cpu_temp(id); 116 return sprintf(buf, "%d\n", value); 117 } 118 119 static int create_sysfs_cputemp_files(struct kobject *kobj) 120 { 121 int i, ret = 0; 122 123 for (i=0; i<nr_packages; i++) 124 ret = sysfs_create_files(kobj, hwmon_cputemp[i]); 125 126 return ret; 127 } 128 129 static void remove_sysfs_cputemp_files(struct kobject *kobj) 130 { 131 int i; 132 133 for (i=0; i<nr_packages; i++) 134 sysfs_remove_files(kobj, hwmon_cputemp[i]); 135 } 136 137 #define CPU_THERMAL_THRESHOLD 90000 138 static struct delayed_work thermal_work; 139 140 static void do_thermal_timer(struct work_struct *work) 141 { 142 int i, value, temp_max = 0; 143 144 for (i=0; i<nr_packages; i++) { 145 value = loongson3_cpu_temp(i); 146 if (value > temp_max) 147 temp_max = value; 148 } 149 150 if (temp_max <= CPU_THERMAL_THRESHOLD) 151 schedule_delayed_work(&thermal_work, msecs_to_jiffies(5000)); 152 else 153 orderly_poweroff(true); 154 } 155 156 static int __init loongson_hwmon_init(void) 157 { 158 int ret; 159 160 pr_info("Loongson Hwmon Enter...\n"); 161 162 cpu_hwmon_dev = hwmon_device_register(NULL); 163 if (IS_ERR(cpu_hwmon_dev)) { 164 ret = -ENOMEM; 165 pr_err("hwmon_device_register fail!\n"); 166 goto fail_hwmon_device_register; 167 } 168 169 nr_packages = loongson_sysconf.nr_cpus / 170 loongson_sysconf.cores_per_package; 171 172 ret = sysfs_create_group(&cpu_hwmon_dev->kobj, 173 &cpu_hwmon_attribute_group); 174 if (ret) { 175 pr_err("fail to create loongson hwmon!\n"); 176 goto fail_sysfs_create_group_hwmon; 177 } 178 179 ret = create_sysfs_cputemp_files(&cpu_hwmon_dev->kobj); 180 if (ret) { 181 pr_err("fail to create cpu temperature interface!\n"); 182 goto fail_create_sysfs_cputemp_files; 183 } 184 185 INIT_DEFERRABLE_WORK(&thermal_work, do_thermal_timer); 186 schedule_delayed_work(&thermal_work, msecs_to_jiffies(20000)); 187 188 return ret; 189 190 fail_create_sysfs_cputemp_files: 191 sysfs_remove_group(&cpu_hwmon_dev->kobj, 192 &cpu_hwmon_attribute_group); 193 194 fail_sysfs_create_group_hwmon: 195 hwmon_device_unregister(cpu_hwmon_dev); 196 197 fail_hwmon_device_register: 198 return ret; 199 } 200 201 static void __exit loongson_hwmon_exit(void) 202 { 203 cancel_delayed_work_sync(&thermal_work); 204 remove_sysfs_cputemp_files(&cpu_hwmon_dev->kobj); 205 sysfs_remove_group(&cpu_hwmon_dev->kobj, 206 &cpu_hwmon_attribute_group); 207 hwmon_device_unregister(cpu_hwmon_dev); 208 } 209 210 module_init(loongson_hwmon_init); 211 module_exit(loongson_hwmon_exit); 212 213 MODULE_AUTHOR("Yu Xiang <xiangy@lemote.com>"); 214 MODULE_AUTHOR("Huacai Chen <chenhc@lemote.com>"); 215 MODULE_DESCRIPTION("Loongson CPU Hwmon driver"); 216 MODULE_LICENSE("GPL"); 217