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)