kernel-ark/drivers/hwmon/k8temp.c
Jean Delvare cd4de21f7e hwmon: (k8temp) Bypass core swapping on single-core processors
Commit a2e066bba2 introduced core
swapping for CPU models 64 and later. I recently had a report about
a Sempron 3200+, model 95, for which this patch broke temperature
reading. It happens that this is a single-core processor, so the
effect of the swapping was to read a temperature value for a core
that didn't exist, leading to an incorrect value (-49 degrees C.)

Disabling core swapping on singe-core processors should fix this.

Additional comment from Andreas:

The BKDG says

  Thermal Sensor Core Select (ThermSenseCoreSel)-Bit 2. This bit
  selects the CPU whose temperature is reported in the CurTemp
  field. This bit only applies to dual core processors. For
  single core processors CPU0 Thermal Sensor is always selected.

k8temp_probe() correctly detected that SEL_CORE can't be used on single
core CPU. Thus k8temp did never update the temperature values stored
in temp[1][x] and -49 degrees was reported. For single core CPUs we
must use the values read into temp[0][x].

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Rick Moritz <rhavin@gmx.net>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: stable@kernel.org
2010-06-20 09:22:32 +02:00

332 lines
8.9 KiB
C

/*
* k8temp.c - Linux kernel module for hardware monitoring
*
* Copyright (C) 2006 Rudolf Marek <r.marek@assembler.cz>
*
* Inspired from the w83785 and amd756 drivers.
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/pci.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <asm/processor.h>
#define TEMP_FROM_REG(val) (((((val) >> 16) & 0xff) - 49) * 1000)
#define REG_TEMP 0xe4
#define SEL_PLACE 0x40
#define SEL_CORE 0x04
struct k8temp_data {
struct device *hwmon_dev;
struct mutex update_lock;
const char *name;
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */
/* registers values */
u8 sensorsp; /* sensor presence bits - SEL_CORE & SEL_PLACE */
u32 temp[2][2]; /* core, place */
u8 swap_core_select; /* meaning of SEL_CORE is inverted */
u32 temp_offset;
};
static struct k8temp_data *k8temp_update_device(struct device *dev)
{
struct k8temp_data *data = dev_get_drvdata(dev);
struct pci_dev *pdev = to_pci_dev(dev);
u8 tmp;
mutex_lock(&data->update_lock);
if (!data->valid
|| time_after(jiffies, data->last_updated + HZ)) {
pci_read_config_byte(pdev, REG_TEMP, &tmp);
tmp &= ~(SEL_PLACE | SEL_CORE); /* Select sensor 0, core0 */
pci_write_config_byte(pdev, REG_TEMP, tmp);
pci_read_config_dword(pdev, REG_TEMP, &data->temp[0][0]);
if (data->sensorsp & SEL_PLACE) {
tmp |= SEL_PLACE; /* Select sensor 1, core0 */
pci_write_config_byte(pdev, REG_TEMP, tmp);
pci_read_config_dword(pdev, REG_TEMP,
&data->temp[0][1]);
}
if (data->sensorsp & SEL_CORE) {
tmp &= ~SEL_PLACE; /* Select sensor 0, core1 */
tmp |= SEL_CORE;
pci_write_config_byte(pdev, REG_TEMP, tmp);
pci_read_config_dword(pdev, REG_TEMP,
&data->temp[1][0]);
if (data->sensorsp & SEL_PLACE) {
tmp |= SEL_PLACE; /* Select sensor 1, core1 */
pci_write_config_byte(pdev, REG_TEMP, tmp);
pci_read_config_dword(pdev, REG_TEMP,
&data->temp[1][1]);
}
}
data->last_updated = jiffies;
data->valid = 1;
}
mutex_unlock(&data->update_lock);
return data;
}
/*
* Sysfs stuff
*/
static ssize_t show_name(struct device *dev, struct device_attribute
*devattr, char *buf)
{
struct k8temp_data *data = dev_get_drvdata(dev);
return sprintf(buf, "%s\n", data->name);
}
static ssize_t show_temp(struct device *dev,
struct device_attribute *devattr, char *buf)
{
struct sensor_device_attribute_2 *attr =
to_sensor_dev_attr_2(devattr);
int core = attr->nr;
int place = attr->index;
int temp;
struct k8temp_data *data = k8temp_update_device(dev);
if (data->swap_core_select && (data->sensorsp & SEL_CORE))
core = core ? 0 : 1;
temp = TEMP_FROM_REG(data->temp[core][place]) + data->temp_offset;
return sprintf(buf, "%d\n", temp);
}
/* core, place */
static SENSOR_DEVICE_ATTR_2(temp1_input, S_IRUGO, show_temp, NULL, 0, 0);
static SENSOR_DEVICE_ATTR_2(temp2_input, S_IRUGO, show_temp, NULL, 0, 1);
static SENSOR_DEVICE_ATTR_2(temp3_input, S_IRUGO, show_temp, NULL, 1, 0);
static SENSOR_DEVICE_ATTR_2(temp4_input, S_IRUGO, show_temp, NULL, 1, 1);
static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
static const struct pci_device_id k8temp_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
{ 0 },
};
MODULE_DEVICE_TABLE(pci, k8temp_ids);
static int __devinit k8temp_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
int err;
u8 scfg;
u32 temp;
u8 model, stepping;
struct k8temp_data *data;
if (!(data = kzalloc(sizeof(struct k8temp_data), GFP_KERNEL))) {
err = -ENOMEM;
goto exit;
}
model = boot_cpu_data.x86_model;
stepping = boot_cpu_data.x86_mask;
switch (boot_cpu_data.x86) {
case 0xf:
/* feature available since SH-C0, exclude older revisions */
if (((model == 4) && (stepping == 0)) ||
((model == 5) && (stepping <= 1))) {
err = -ENODEV;
goto exit_free;
}
/*
* AMD NPT family 0fh, i.e. RevF and RevG:
* meaning of SEL_CORE bit is inverted
*/
if (model >= 0x40) {
data->swap_core_select = 1;
dev_warn(&pdev->dev, "Temperature readouts might be "
"wrong - check erratum #141\n");
}
if ((model >= 0x69) &&
!(model == 0xc1 || model == 0x6c || model == 0x7c)) {
/*
* RevG desktop CPUs (i.e. no socket S1G1 parts)
* need additional offset, otherwise reported
* temperature is below ambient temperature
*/
data->temp_offset = 21000;
}
break;
}
pci_read_config_byte(pdev, REG_TEMP, &scfg);
scfg &= ~(SEL_PLACE | SEL_CORE); /* Select sensor 0, core0 */
pci_write_config_byte(pdev, REG_TEMP, scfg);
pci_read_config_byte(pdev, REG_TEMP, &scfg);
if (scfg & (SEL_PLACE | SEL_CORE)) {
dev_err(&pdev->dev, "Configuration bit(s) stuck at 1!\n");
err = -ENODEV;
goto exit_free;
}
scfg |= (SEL_PLACE | SEL_CORE);
pci_write_config_byte(pdev, REG_TEMP, scfg);
/* now we know if we can change core and/or sensor */
pci_read_config_byte(pdev, REG_TEMP, &data->sensorsp);
if (data->sensorsp & SEL_PLACE) {
scfg &= ~SEL_CORE; /* Select sensor 1, core0 */
pci_write_config_byte(pdev, REG_TEMP, scfg);
pci_read_config_dword(pdev, REG_TEMP, &temp);
scfg |= SEL_CORE; /* prepare for next selection */
if (!((temp >> 16) & 0xff)) /* if temp is 0 -49C is not likely */
data->sensorsp &= ~SEL_PLACE;
}
if (data->sensorsp & SEL_CORE) {
scfg &= ~SEL_PLACE; /* Select sensor 0, core1 */
pci_write_config_byte(pdev, REG_TEMP, scfg);
pci_read_config_dword(pdev, REG_TEMP, &temp);
if (!((temp >> 16) & 0xff)) /* if temp is 0 -49C is not likely */
data->sensorsp &= ~SEL_CORE;
}
data->name = "k8temp";
mutex_init(&data->update_lock);
dev_set_drvdata(&pdev->dev, data);
/* Register sysfs hooks */
err = device_create_file(&pdev->dev,
&sensor_dev_attr_temp1_input.dev_attr);
if (err)
goto exit_remove;
/* sensor can be changed and reports something */
if (data->sensorsp & SEL_PLACE) {
err = device_create_file(&pdev->dev,
&sensor_dev_attr_temp2_input.dev_attr);
if (err)
goto exit_remove;
}
/* core can be changed and reports something */
if (data->sensorsp & SEL_CORE) {
err = device_create_file(&pdev->dev,
&sensor_dev_attr_temp3_input.dev_attr);
if (err)
goto exit_remove;
if (data->sensorsp & SEL_PLACE)
err = device_create_file(&pdev->dev,
&sensor_dev_attr_temp4_input.
dev_attr);
if (err)
goto exit_remove;
}
err = device_create_file(&pdev->dev, &dev_attr_name);
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);
goto exit_remove;
}
return 0;
exit_remove:
device_remove_file(&pdev->dev,
&sensor_dev_attr_temp1_input.dev_attr);
device_remove_file(&pdev->dev,
&sensor_dev_attr_temp2_input.dev_attr);
device_remove_file(&pdev->dev,
&sensor_dev_attr_temp3_input.dev_attr);
device_remove_file(&pdev->dev,
&sensor_dev_attr_temp4_input.dev_attr);
device_remove_file(&pdev->dev, &dev_attr_name);
exit_free:
dev_set_drvdata(&pdev->dev, NULL);
kfree(data);
exit:
return err;
}
static void __devexit k8temp_remove(struct pci_dev *pdev)
{
struct k8temp_data *data = dev_get_drvdata(&pdev->dev);
hwmon_device_unregister(data->hwmon_dev);
device_remove_file(&pdev->dev,
&sensor_dev_attr_temp1_input.dev_attr);
device_remove_file(&pdev->dev,
&sensor_dev_attr_temp2_input.dev_attr);
device_remove_file(&pdev->dev,
&sensor_dev_attr_temp3_input.dev_attr);
device_remove_file(&pdev->dev,
&sensor_dev_attr_temp4_input.dev_attr);
device_remove_file(&pdev->dev, &dev_attr_name);
dev_set_drvdata(&pdev->dev, NULL);
kfree(data);
}
static struct pci_driver k8temp_driver = {
.name = "k8temp",
.id_table = k8temp_ids,
.probe = k8temp_probe,
.remove = __devexit_p(k8temp_remove),
};
static int __init k8temp_init(void)
{
return pci_register_driver(&k8temp_driver);
}
static void __exit k8temp_exit(void)
{
pci_unregister_driver(&k8temp_driver);
}
MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
MODULE_DESCRIPTION("AMD K8 core temperature monitor");
MODULE_LICENSE("GPL");
module_init(k8temp_init)
module_exit(k8temp_exit)