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 = 0; 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 */ 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 ssize_t get_hwmon_name(struct device *dev, 59 struct device_attribute *attr, char *buf); 60 static SENSOR_DEVICE_ATTR(name, S_IRUGO, get_hwmon_name, NULL, 0); 61 62 static struct attribute *cpu_hwmon_attributes[] = { 63 &sensor_dev_attr_name.dev_attr.attr, 64 NULL 65 }; 66 67 /* Hwmon device attribute group */ 68 static struct attribute_group cpu_hwmon_attribute_group = { 69 .attrs = cpu_hwmon_attributes, 70 }; 71 72 /* Hwmon device get name */ 73 static ssize_t get_hwmon_name(struct device *dev, 74 struct device_attribute *attr, char *buf) 75 { 76 return sprintf(buf, "cpu-hwmon\n"); 77 } 78 79 static ssize_t get_cpu_temp(struct device *dev, 80 struct device_attribute *attr, char *buf); 81 static ssize_t cpu_temp_label(struct device *dev, 82 struct device_attribute *attr, char *buf); 83 84 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, get_cpu_temp, NULL, 1); 85 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, cpu_temp_label, NULL, 1); 86 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, get_cpu_temp, NULL, 2); 87 static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, cpu_temp_label, NULL, 2); 88 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, get_cpu_temp, NULL, 3); 89 static SENSOR_DEVICE_ATTR(temp3_label, S_IRUGO, cpu_temp_label, NULL, 3); 90 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, get_cpu_temp, NULL, 4); 91 static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, cpu_temp_label, NULL, 4); 92 93 static const struct attribute *hwmon_cputemp[4][3] = { 94 { 95 &sensor_dev_attr_temp1_input.dev_attr.attr, 96 &sensor_dev_attr_temp1_label.dev_attr.attr, 97 NULL 98 }, 99 { 100 &sensor_dev_attr_temp2_input.dev_attr.attr, 101 &sensor_dev_attr_temp2_label.dev_attr.attr, 102 NULL 103 }, 104 { 105 &sensor_dev_attr_temp3_input.dev_attr.attr, 106 &sensor_dev_attr_temp3_label.dev_attr.attr, 107 NULL 108 }, 109 { 110 &sensor_dev_attr_temp4_input.dev_attr.attr, 111 &sensor_dev_attr_temp4_label.dev_attr.attr, 112 NULL 113 } 114 }; 115 116 static ssize_t cpu_temp_label(struct device *dev, 117 struct device_attribute *attr, char *buf) 118 { 119 int id = (to_sensor_dev_attr(attr))->index - 1; 120 return sprintf(buf, "CPU %d Temperature\n", id); 121 } 122 123 static ssize_t get_cpu_temp(struct device *dev, 124 struct device_attribute *attr, char *buf) 125 { 126 int id = (to_sensor_dev_attr(attr))->index - 1; 127 int value = loongson3_cpu_temp(id); 128 return sprintf(buf, "%d\n", value); 129 } 130 131 static int create_sysfs_cputemp_files(struct kobject *kobj) 132 { 133 int i, ret = 0; 134 135 for (i=0; i<nr_packages; i++) 136 ret = sysfs_create_files(kobj, hwmon_cputemp[i]); 137 138 return ret; 139 } 140 141 static void remove_sysfs_cputemp_files(struct kobject *kobj) 142 { 143 int i; 144 145 for (i=0; i<nr_packages; i++) 146 sysfs_remove_files(kobj, hwmon_cputemp[i]); 147 } 148 149 #define CPU_THERMAL_THRESHOLD 90000 150 static struct delayed_work thermal_work; 151 152 static void do_thermal_timer(struct work_struct *work) 153 { 154 int i, value, temp_max = 0; 155 156 for (i=0; i<nr_packages; i++) { 157 value = loongson3_cpu_temp(i); 158 if (value > temp_max) 159 temp_max = value; 160 } 161 162 if (temp_max <= CPU_THERMAL_THRESHOLD) 163 schedule_delayed_work(&thermal_work, msecs_to_jiffies(5000)); 164 else 165 orderly_poweroff(true); 166 } 167 168 static int __init loongson_hwmon_init(void) 169 { 170 int ret; 171 172 pr_info("Loongson Hwmon Enter...\n"); 173 174 if (cpu_has_csr()) 175 csr_temp_enable = csr_readl(LOONGSON_CSR_FEATURES) & LOONGSON_CSRF_TEMP; 176 177 cpu_hwmon_dev = hwmon_device_register(NULL); 178 if (IS_ERR(cpu_hwmon_dev)) { 179 ret = PTR_ERR(cpu_hwmon_dev); 180 pr_err("hwmon_device_register fail!\n"); 181 goto fail_hwmon_device_register; 182 } 183 184 nr_packages = loongson_sysconf.nr_cpus / 185 loongson_sysconf.cores_per_package; 186 187 ret = sysfs_create_group(&cpu_hwmon_dev->kobj, 188 &cpu_hwmon_attribute_group); 189 if (ret) { 190 pr_err("fail to create loongson hwmon!\n"); 191 goto fail_sysfs_create_group_hwmon; 192 } 193 194 ret = create_sysfs_cputemp_files(&cpu_hwmon_dev->kobj); 195 if (ret) { 196 pr_err("fail to create cpu temperature interface!\n"); 197 goto fail_create_sysfs_cputemp_files; 198 } 199 200 INIT_DEFERRABLE_WORK(&thermal_work, do_thermal_timer); 201 schedule_delayed_work(&thermal_work, msecs_to_jiffies(20000)); 202 203 return ret; 204 205 fail_create_sysfs_cputemp_files: 206 sysfs_remove_group(&cpu_hwmon_dev->kobj, 207 &cpu_hwmon_attribute_group); 208 209 fail_sysfs_create_group_hwmon: 210 hwmon_device_unregister(cpu_hwmon_dev); 211 212 fail_hwmon_device_register: 213 return ret; 214 } 215 216 static void __exit loongson_hwmon_exit(void) 217 { 218 cancel_delayed_work_sync(&thermal_work); 219 remove_sysfs_cputemp_files(&cpu_hwmon_dev->kobj); 220 sysfs_remove_group(&cpu_hwmon_dev->kobj, 221 &cpu_hwmon_attribute_group); 222 hwmon_device_unregister(cpu_hwmon_dev); 223 } 224 225 module_init(loongson_hwmon_init); 226 module_exit(loongson_hwmon_exit); 227 228 MODULE_AUTHOR("Yu Xiang <xiangy@lemote.com>"); 229 MODULE_AUTHOR("Huacai Chen <chenhc@lemote.com>"); 230 MODULE_DESCRIPTION("Loongson CPU Hwmon driver"); 231 MODULE_LICENSE("GPL"); 232