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 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
  66 static 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
  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 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
  96 static 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
 106 static struct attribute_group cpu_hwmon_group = {
 107         .attrs = cpu_hwmon_attributes,
 108         .is_visible = cpu_hwmon_is_visible,
 109 };
 110
 111 static const struct attribute_group *cpu_hwmon_groups[] = {
 112         &cpu_hwmon_group,
 113         NULL
 114 };
 115
 116 #define CPU_THERMAL_THRESHOLD 90000
 117 static struct delayed_work thermal_work;
 118
 119 static 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
 134 static 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
 158 static void __exit loongson_hwmon_exit(void)
 159 {
 160         cancel_delayed_work_sync(&thermal_work);
 161         hwmon_device_unregister(cpu_hwmon_dev);
 162 }
 163
 164 module_init(loongson_hwmon_init);
 165 module_exit(loongson_hwmon_exit);
 166
 167 MODULE_AUTHOR("Yu Xiang <xiangy@lemote.com>");
 168 MODULE_AUTHOR("Huacai Chen <chenhc@lemote.com>");
 169 MODULE_DESCRIPTION("Loongson CPU Hwmon driver");
 170 MODULE_LICENSE("GPL");