/*
* via-cputemp.c - Driver for VIA CPU core temperature monitoring
* Copyright (C) 2009 VIA Technologies, Inc.
*
* based on existing coretemp.c, which is
*
* Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
*
* 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/hwmon.h>
#include <linux/hwmon-vid.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/cpu_device_id.h>
#define DRVNAME "via_cputemp"
enum { SHOW_TEMP, SHOW_LABEL, SHOW_NAME };
/*
* Functions declaration
*/
struct via_cputemp_data {
struct device *hwmon_dev;
const char *name;
u8 vrm;
u32 id;
u32 msr_temp;
u32 msr_vid;
};
/*
* 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 via_cputemp_data *data = dev_get_drvdata(dev);
if (attr->index == SHOW_NAME)
ret = sprintf(buf, "%s\n", data->name);
else /* show label */
ret = sprintf(buf, "Core %d\n", data->id);
return ret;
}
static ssize_t show_temp(struct device *dev,
struct device_attribute *devattr, char *buf)
{
struct via_cputemp_data *data = dev_get_drvdata(dev);
u32 eax, edx;
int err;
err = rdmsr_safe_on_cpu(data->id, data->msr_temp, &eax, &edx);
if (err)
return -EAGAIN;
return sprintf(buf, "%lu\n", ((unsigned long)eax & 0xffffff) * 1000);
}
static ssize_t show_cpu_vid(struct device *dev,
struct device_attribute *devattr, char *buf)
{
struct via_cputemp_data *data = dev_get_drvdata(dev);
u32 eax, edx;
int err;
err = rdmsr_safe_on_cpu(data->id, data->msr_vid, &eax, &edx);
if (err)
return -EAGAIN;
return sprintf(buf, "%d\n", vid_from_reg(~edx & 0x7f, data->vrm));
}
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL,
SHOW_TEMP);
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 *via_cputemp_attributes[] = {
&sensor_dev_attr_name.dev_attr.attr,
&sensor_dev_attr_temp1_label.dev_attr.attr,
&sensor_dev_attr_temp1_input.dev_attr.attr,
NULL
};
static const struct attribute_group via_cputemp_group = {
.attrs = via_cputemp_attributes,
};
/* Optional attributes */
static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_cpu_vid, NULL);
static int via_cputemp_probe(struct platform_device *pdev)
{
struct via_cputemp_data *data;
struct cpuinfo_x86 *c = &cpu_data(pdev->id);
int err;
u32 eax, edx;
data = devm_kzalloc(&pdev->dev, sizeof(struct via_cputemp_data),
GFP_KERNEL);
if (!data)
return -ENOMEM;
data->id = pdev->id;
data->name = "via_cputemp";
switch (c->x86_model) {
case 0xA:
/* C7 A */
case 0xD:
/* C7 D */
data->msr_temp = 0x1169;
data->msr_vid = 0x198;
break;
case 0xF:
/* Nano */
data->msr_temp = 0x1423;
break;
default:
return -ENODEV;
}
/* test if we can access the TEMPERATURE MSR */
err = rdmsr_safe_on_cpu(data->id, data->msr_temp, &eax, &edx);
if (err) {
dev_err(&pdev->dev,
"Unable to access TEMPERATURE MSR, giving up\n");
return err;
}
platform_set_drvdata(pdev, data);
err = sysfs_create_group(&pdev->dev.kobj, &via_cputemp_group);
if (err)
return err;
if (data->msr_vid)
data->vrm = vid_which_vrm();
if (data->vrm) {
err = device_create_file(&pdev->dev, &dev_attr_cpu0_vid);
if (err)
goto exit_remove;
}
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_remove;
}
return 0;
exit_remove:
if (data->vrm)
device_remove_file(&pdev->dev, &dev_attr_cpu0_vid);
sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group);
return err;
}
static int via_cputemp_remove(struct platform_device *pdev)
{
struct via_cputemp_data *data = platform_get_drvdata(pdev);
hwmon_device_unregister(data->hwmon_dev);
if (data->vrm)
device_remove_file(&pdev->dev, &dev_attr_cpu0_vid);
sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group);
return 0;
}
static struct platform_driver via_cputemp_driver = {
.driver = {
.owner = THIS_MODULE,
.name = DRVNAME,
},
.probe = via_cputemp_probe,
.remove = via_cputemp_remove,
};
struct pdev_entry {
struct list_head list;
struct platform_device *pdev;
unsigned int cpu;
};
static LIST_HEAD(pdev_list);
static DEFINE_MUTEX(pdev_list_mutex);
static int via_cputemp_device_add(unsigned int cpu)
{
int err;
struct platform_device *pdev;
struct pdev_entry *pdev_entry;
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;
}
pdev_entry->pdev = pdev;
pdev_entry->cpu = cpu;
mutex_lock(&pdev_list_mutex);
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:
return err;
}
static void via_cputemp_device_remove(unsigned int cpu)
{
struct pdev_entry *p;
mutex_lock(&pdev_list_mutex);
list_for_each_entry(p, &pdev_list, list) {
if (p->cpu == cpu) {
platform_device_unregister(p->pdev);
list_del(&p->list);
mutex_unlock(&pdev_list_mutex);
kfree(p);
return;
}
}
mutex_unlock(&pdev_list_mutex);
}
static int via_cputemp_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:
via_cputemp_device_add(cpu);
break;
case CPU_DOWN_PREPARE:
via_cputemp_device_remove(cpu);
break;
}
return NOTIFY_OK;
}
static struct notifier_block via_cputemp_cpu_notifier __refdata = {
.notifier_call = via_cputemp_cpu_callback,
};
static const struct x86_cpu_id __initconst cputemp_ids[] = {
{ X86_VENDOR_CENTAUR, 6, 0xa, }, /* C7 A */
{ X86_VENDOR_CENTAUR, 6, 0xd, }, /* C7 D */
{ X86_VENDOR_CENTAUR, 6, 0xf, }, /* Nano */
{}
};
MODULE_DEVICE_TABLE(x86cpu, cputemp_ids);
static int __init via_cputemp_init(void)
{
int i, err;
if (!x86_match_cpu(cputemp_ids))
return -ENODEV;
err = platform_driver_register(&via_cputemp_driver);
if (err)
goto exit;
get_online_cpus();
for_each_online_cpu(i) {
struct cpuinfo_x86 *c = &cpu_data(i);
if (c->x86 != 6)
continue;
if (c->x86_model < 0x0a)
continue;
if (c->x86_model > 0x0f) {
pr_warn("Unknown CPU model 0x%x\n", c->x86_model);
continue;
}
via_cputemp_device_add(i);
}
#ifndef CONFIG_HOTPLUG_CPU
if (list_empty(&pdev_list)) {
put_online_cpus();
err = -ENODEV;
goto exit_driver_unreg;
}
#endif
register_hotcpu_notifier(&via_cputemp_cpu_notifier);
put_online_cpus();
return 0;
#ifndef CONFIG_HOTPLUG_CPU
exit_driver_unreg:
platform_driver_unregister(&via_cputemp_driver);
#endif
exit:
return err;
}
static void __exit via_cputemp_exit(void)
{
struct pdev_entry *p, *n;
get_online_cpus();
unregister_hotcpu_notifier(&via_cputemp_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);
put_online_cpus();
platform_driver_unregister(&via_cputemp_driver);
}
MODULE_AUTHOR("Harald Welte <HaraldWelte@viatech.com>");
MODULE_DESCRIPTION("VIA CPU temperature monitor");
MODULE_LICENSE("GPL");
module_init(via_cputemp_init)
module_exit(via_cputemp_exit)
