cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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cpu_hwmon.c (4429B)

      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");