drivers/platform/mips/cpu_hwmon.c

   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  */
  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
 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
 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
 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
 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
 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
 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
 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");