hwmon: New driver for AMD Family 10h/11h CPUs

This adds a driver for the internal temperature sensor of AMD Family 10h
and 11h CPUs.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 197 insertions, 0 deletions

diff --git a/drivers/hwmon/k10temp.c b/drivers/hwmon/k10temp.c
new file mode 100644
index 000000000000..d8a26d16d948
--- /dev/null
+++ b/drivers/hwmon/k10temp.c
@@ -0,0 +1,197 @@
+/*
+ * k10temp.c - AMD Family 10h/11h processor hardware monitoring
+ *
+ * Copyright (c) 2009 Clemens Ladisch <clemens@ladisch.de>
+ *
+ *
+ * This driver is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This driver 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 driver; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <asm/processor.h>
+
+MODULE_DESCRIPTION("AMD Family 10h/11h CPU core temperature monitor");
+MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
+MODULE_LICENSE("GPL");
+
+static bool force;
+module_param(force, bool, 0444);
+MODULE_PARM_DESC(force, "force loading on processors with erratum 319");
+
+#define REG_HARDWARE_THERMAL_CONTROL	0x64
+#define  HTC_ENABLE			0x00000001
+
+#define REG_REPORTED_TEMPERATURE	0xa4
+
+#define REG_NORTHBRIDGE_CAPABILITIES	0xe8
+#define  NB_CAP_HTC			0x00000400
+
+static ssize_t show_temp(struct device *dev,
+			 struct device_attribute *attr, char *buf)
+{
+	u32 regval;
+
+	pci_read_config_dword(to_pci_dev(dev),
+			      REG_REPORTED_TEMPERATURE, &regval);
+	return sprintf(buf, "%u\n", (regval >> 21) * 125);
+}
+
+static ssize_t show_temp_max(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%d\n", 70 * 1000);
+}
+
+static ssize_t show_temp_crit(struct device *dev,
+			      struct device_attribute *devattr, char *buf)
+{
+	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+	int show_hyst = attr->index;
+	u32 regval;
+	int value;
+
+	pci_read_config_dword(to_pci_dev(dev),
+			      REG_HARDWARE_THERMAL_CONTROL, &regval);
+	value = ((regval >> 16) & 0x7f) * 500 + 52000;
+	if (show_hyst)
+		value -= ((regval >> 24) & 0xf) * 500;
+	return sprintf(buf, "%d\n", value);
+}
+
+static ssize_t show_name(struct device *dev,
+			 struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "k10temp\n");
+}
+
+static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
+static DEVICE_ATTR(temp1_max, S_IRUGO, show_temp_max, NULL);
+static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp_crit, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO, show_temp_crit, NULL, 1);
+static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
+
+static bool __devinit has_erratum_319(void)
+{
+	/*
+	 * Erratum 319: The thermal sensor of older Family 10h processors
+	 *              (B steppings) may be unreliable.
+	 */
+	return boot_cpu_data.x86 == 0x10 && boot_cpu_data.x86_model <= 2;
+}
+
+static int __devinit k10temp_probe(struct pci_dev *pdev,
+				   const struct pci_device_id *id)
+{
+	struct device *hwmon_dev;
+	u32 reg_caps, reg_htc;
+	int err;
+
+	if (has_erratum_319() && !force) {
+		dev_err(&pdev->dev,
+			"unreliable CPU thermal sensor; monitoring disabled\n");
+		err = -ENODEV;
+		goto exit;
+	}
+
+	err = device_create_file(&pdev->dev, &dev_attr_temp1_input);
+	if (err)
+		goto exit;
+	err = device_create_file(&pdev->dev, &dev_attr_temp1_max);
+	if (err)
+		goto exit_remove;
+
+	pci_read_config_dword(pdev, REG_NORTHBRIDGE_CAPABILITIES, &reg_caps);
+	pci_read_config_dword(pdev, REG_HARDWARE_THERMAL_CONTROL, &reg_htc);
+	if ((reg_caps & NB_CAP_HTC) && (reg_htc & HTC_ENABLE)) {
+		err = device_create_file(&pdev->dev,
+				&sensor_dev_attr_temp1_crit.dev_attr);
+		if (err)
+			goto exit_remove;
+		err = device_create_file(&pdev->dev,
+				&sensor_dev_attr_temp1_crit_hyst.dev_attr);
+		if (err)
+			goto exit_remove;
+	}
+
+	err = device_create_file(&pdev->dev, &dev_attr_name);
+	if (err)
+		goto exit_remove;
+
+	hwmon_dev = hwmon_device_register(&pdev->dev);
+	if (IS_ERR(hwmon_dev)) {
+		err = PTR_ERR(hwmon_dev);
+		goto exit_remove;
+	}
+	dev_set_drvdata(&pdev->dev, hwmon_dev);
+
+	if (has_erratum_319() && force)
+		dev_warn(&pdev->dev,
+			 "unreliable CPU thermal sensor; check erratum 319\n");
+	return 0;
+
+exit_remove:
+	device_remove_file(&pdev->dev, &dev_attr_name);
+	device_remove_file(&pdev->dev, &dev_attr_temp1_input);
+	device_remove_file(&pdev->dev, &dev_attr_temp1_max);
+	device_remove_file(&pdev->dev,
+			   &sensor_dev_attr_temp1_crit.dev_attr);
+	device_remove_file(&pdev->dev,
+			   &sensor_dev_attr_temp1_crit_hyst.dev_attr);
+exit:
+	return err;
+}
+
+static void __devexit k10temp_remove(struct pci_dev *pdev)
+{
+	hwmon_device_unregister(dev_get_drvdata(&pdev->dev));
+	device_remove_file(&pdev->dev, &dev_attr_name);
+	device_remove_file(&pdev->dev, &dev_attr_temp1_input);
+	device_remove_file(&pdev->dev, &dev_attr_temp1_max);
+	device_remove_file(&pdev->dev,
+			   &sensor_dev_attr_temp1_crit.dev_attr);
+	device_remove_file(&pdev->dev,
+			   &sensor_dev_attr_temp1_crit_hyst.dev_attr);
+	dev_set_drvdata(&pdev->dev, NULL);
+}
+
+static struct pci_device_id k10temp_id_table[] = {
+	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
+	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_11H_NB_MISC) },
+	{}
+};
+MODULE_DEVICE_TABLE(pci, k10temp_id_table);
+
+static struct pci_driver k10temp_driver = {
+	.name = "k10temp",
+	.id_table = k10temp_id_table,
+	.probe = k10temp_probe,
+	.remove = __devexit_p(k10temp_remove),
+};
+
+static int __init k10temp_init(void)
+{
+	return pci_register_driver(&k10temp_driver);
+}
+
+static void __exit k10temp_exit(void)
+{
+	pci_unregister_driver(&k10temp_driver);
+}
+
+module_init(k10temp_init)
+module_exit(k10temp_exit)