- 根目录:
- drivers
- hwmon
- pkgtemp.c
/*
* pkgtemp.c - Linux kernel module for processor package hardware monitoring
*
* Copyright (C) 2010 Fenghua Yu <fenghua.yu@intel.com>
*
* Inspired from many hwmon drivers especially coretemp.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/hwmon.h>
#include <linux/sysfs.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/platform_device.h>
#include <linux/cpu.h>
#include <asm/msr.h>
#include <asm/processor.h>
#include <asm/smp.h>
#define DRVNAME "pkgtemp"
enum { SHOW_TEMP, SHOW_TJMAX, SHOW_TTARGET, SHOW_LABEL, SHOW_NAME };
/*
* Functions declaration
*/
static struct pkgtemp_data *pkgtemp_update_device(struct device *dev);
struct pkgtemp_data {
struct device *hwmon_dev;
struct mutex update_lock;
const char *name;
u32 id;
u16 phys_proc_id;
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */
int temp;
int tjmax;
int ttarget;
u8 alarm;
};
/*
* Sysfs stuff
*/
static ssize_t show_name(struct device *dev, struct device_attribute
*devattr, char *buf)
{
int ret;
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct pkgtemp_data *data = dev_get_drvdata(dev);
if (attr->index == SHOW_NAME)
ret = sprintf(buf, "%s\n", data->name);
else /* show label */
ret = sprintf(buf, "physical id %d\n",
data->phys_proc_id);
return ret;
}
static ssize_t show_alarm(struct device *dev, struct device_attribute
*devattr, char *buf)
{
struct pkgtemp_data *data = pkgtemp_update_device(dev);
/* read the Out-of-spec log, never clear */
return sprintf(buf, "%d\n", data->alarm);
}
static ssize_t show_temp(struct device *dev,
struct device_attribute *devattr, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct pkgtemp_data *data = pkgtemp_update_device(dev);
int err = 0;
if (attr->index == SHOW_TEMP)
err = data->valid ? sprintf(buf, "%d\n", data->temp) : -EAGAIN;
else if (attr->index == SHOW_TJMAX)
err = sprintf(buf, "%d\n", data->tjmax);
else
err = sprintf(buf, "%d\n", data->ttarget);
return err;
}
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, SHOW_TEMP);
static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, SHOW_TJMAX);
static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL, SHOW_TTARGET);
static DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL);
static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_name, NULL, SHOW_LABEL);
static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, SHOW_NAME);
static struct attribute *pkgtemp_attributes[] = {
&sensor_dev_attr_name.dev_attr.attr,
&sensor_dev_attr_temp1_label.dev_attr.attr,
&dev_attr_temp1_crit_alarm.attr,
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp1_crit.dev_attr.attr,
NULL
};
static const struct attribute_group pkgtemp_group = {
.attrs = pkgtemp_attributes,
};
static struct pkgtemp_data *pkgtemp_update_device(struct device *dev)
{
struct pkgtemp_data *data = dev_get_drvdata(dev);
unsigned int cpu;
int err;
mutex_lock(&data->update_lock);
if (!data->valid || time_after(jiffies, data->last_updated + HZ)) {
u32 eax, edx;
data->valid = 0;
cpu = data->id;
err = rdmsr_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_STATUS,
&eax, &edx);
if (!err) {
data->alarm = (eax >> 5) & 1;
data->temp = data->tjmax - (((eax >> 16)
& 0x7f) * 1000);
data->valid = 1;
} else
dev_dbg(dev, "Temperature data invalid (0x%x)\n", eax);
data->last_updated = jiffies;
}
mutex_unlock(&data->update_lock);
return data;
}
static int get_tjmax(int cpu, struct device *dev)
{
int default_tjmax = 100000;
int err;
u32 eax, edx;
u32 val;
/* IA32_TEMPERATURE_TARGET contains the TjMax value */
err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
if (!err) {
val = (eax >> 16) & 0xff;
if ((val > 80) && (val < 120)) {
dev_info(dev, "TjMax is %d C.\n", val);
return val * 1000;
}
}
dev_warn(dev, "Unable to read TjMax from CPU.\n");
return default_tjmax;
}
static int __devinit pkgtemp_probe(struct platform_device *pdev)
{
struct pkgtemp_data *data;
int err;
u32 eax, edx;
#ifdef CONFIG_SMP
struct cpuinfo_x86 *c = &cpu_data(pdev->id);
#endif
data = kzalloc(sizeof(struct pkgtemp_data), GFP_KERNEL);
if (!data) {
err = -ENOMEM;
dev_err(&pdev->dev, "Out of memory\n");
goto exit;
}
data->id = pdev->id;
#ifdef CONFIG_SMP
data->phys_proc_id = c->phys_proc_id;
#endif
data->name = "pkgtemp";
mutex_init(&data->update_lock);
/* test if we can access the THERM_STATUS MSR */
err = rdmsr_safe_on_cpu(data->id, MSR_IA32_PACKAGE_THERM_STATUS,
&eax, &edx);
if (err) {
dev_err(&pdev->dev,
"Unable to access THERM_STATUS MSR, giving up\n");
goto exit_free;
}
data->tjmax = get_tjmax(data->id, &pdev->dev);
platform_set_drvdata(pdev, data);
err = rdmsr_safe_on_cpu(data->id, MSR_IA32_TEMPERATURE_TARGET,
&eax, &edx);
if (err) {
dev_warn(&pdev->dev, "Unable to read"
" IA32_TEMPERATURE_TARGET MSR\n");
} else {
data->ttarget = data->tjmax - (((eax >> 8) & 0xff) * 1000);
err = device_create_file(&pdev->dev,
&sensor_dev_attr_temp1_max.dev_attr);
if (err)
goto exit_free;
}
err = sysfs_create_group(&pdev->dev.kobj, &pkgtemp_group);
if (err)
goto exit_dev;
data->hwmon_dev = hwmon_device_register(&pdev->dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
dev_err(&pdev->dev, "Class registration failed (%d)\n",
err);
goto exit_class;
}
return 0;
exit_class:
sysfs_remove_group(&pdev->dev.kobj, &pkgtemp_group);
exit_dev:
device_remove_file(&pdev->dev, &sensor_dev_attr_temp1_max.dev_attr);
exit_free:
kfree(data);
exit:
return err;
}
static int __devexit pkgtemp_remove(struct platform_device *pdev)
{
struct pkgtemp_data *data = platform_get_drvdata(pdev);
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&pdev->dev.kobj, &pkgtemp_group);
device_remove_file(&pdev->dev, &sensor_dev_attr_temp1_max.dev_attr);
platform_set_drvdata(pdev, NULL);
kfree(data);
return 0;
}
static struct platform_driver pkgtemp_driver = {
.driver = {
.owner = THIS_MODULE,
.name = DRVNAME,
},
.probe = pkgtemp_probe,
.remove = __devexit_p(pkgtemp_remove),
};
struct pdev_entry {
struct list_head list;
struct platform_device *pdev;
unsigned int cpu;
#ifdef CONFIG_SMP
u16 phys_proc_id;
#endif
};
static LIST_HEAD(pdev_list);
static DEFINE_MUTEX(pdev_list_mutex);
static int __cpuinit pkgtemp_device_add(unsigned int cpu)
{
int err;
struct platform_device *pdev;
struct pdev_entry *pdev_entry;
struct cpuinfo_x86 *c = &cpu_data(cpu);
if (!cpu_has(c, X86_FEATURE_PTS))
return 0;
mutex_lock(&pdev_list_mutex);
#ifdef CONFIG_SMP
/* Only keep the first entry in each package */
list_for_each_entry(pdev_entry, &pdev_list, list) {
if (c->phys_proc_id == pdev_entry->phys_proc_id) {
err = 0; /* Not an error */
goto exit;
}
}
#endif
pdev = platform_device_alloc(DRVNAME, cpu);
if (!pdev) {
err = -ENOMEM;
pr_err("Device allocation failed\n");
goto exit;
}
pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL);
if (!pdev_entry) {
err = -ENOMEM;
goto exit_device_put;
}
err = platform_device_add(pdev);
if (err) {
pr_err("Device addition failed (%d)\n", err);
goto exit_device_free;
}
#ifdef CONFIG_SMP
pdev_entry->phys_proc_id = c->phys_proc_id;
#endif
pdev_entry->pdev = pdev;
pdev_entry->cpu = cpu;
list_add_tail(&pdev_entry->list, &pdev_list);
mutex_unlock(&pdev_list_mutex);
return 0;
exit_device_free:
kfree(pdev_entry);
exit_device_put:
platform_device_put(pdev);
exit:
mutex_unlock(&pdev_list_mutex);
return err;
}
static void __cpuinit pkgtemp_device_remove(unsigned int cpu)
{
struct pdev_entry *p;
unsigned int i;
int err;
mutex_lock(&pdev_list_mutex);
list_for_each_entry(p, &pdev_list, list) {
if (p->cpu != cpu)
continue;
platform_device_unregister(p->pdev);
list_del(&p->list);
mutex_unlock(&pdev_list_mutex);
kfree(p);
for_each_cpu(i, cpu_core_mask(cpu)) {
if (i != cpu) {
err = pkgtemp_device_add(i);
if (!err)
break;
}
}
return;
}
mutex_unlock(&pdev_list_mutex);
}
static int __cpuinit pkgtemp_cpu_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long) hcpu;
switch (action) {
case CPU_ONLINE:
case CPU_DOWN_FAILED:
pkgtemp_device_add(cpu);
break;
case CPU_DOWN_PREPARE:
pkgtemp_device_remove(cpu);
break;
}
return NOTIFY_OK;
}
static struct notifier_block pkgtemp_cpu_notifier __refdata = {
.notifier_call = pkgtemp_cpu_callback,
};
static int __init pkgtemp_init(void)
{
int i, err = -ENODEV;
/* quick check if we run Intel */
if (cpu_data(0).x86_vendor != X86_VENDOR_INTEL)
goto exit;
err = platform_driver_register(&pkgtemp_driver);
if (err)
goto exit;
for_each_online_cpu(i)
pkgtemp_device_add(i);
#ifndef CONFIG_HOTPLUG_CPU
if (list_empty(&pdev_list)) {
err = -ENODEV;
goto exit_driver_unreg;
}
#endif
register_hotcpu_notifier(&pkgtemp_cpu_notifier);
return 0;
#ifndef CONFIG_HOTPLUG_CPU
exit_driver_unreg:
platform_driver_unregister(&pkgtemp_driver);
#endif
exit:
return err;
}
static void __exit pkgtemp_exit(void)
{
struct pdev_entry *p, *n;
unregister_hotcpu_notifier(&pkgtemp_cpu_notifier);
mutex_lock(&pdev_list_mutex);
list_for_each_entry_safe(p, n, &pdev_list, list) {
platform_device_unregister(p->pdev);
list_del(&p->list);
kfree(p);
}
mutex_unlock(&pdev_list_mutex);
platform_driver_unregister(&pkgtemp_driver);
}
MODULE_AUTHOR("Fenghua Yu <fenghua.yu@intel.com>");
MODULE_DESCRIPTION("Intel processor package temperature monitor");
MODULE_LICENSE("GPL");
module_init(pkgtemp_init)
module_exit(pkgtemp_exit)