From: Michal Schmidt <mschmidt@redhat.com>
Date: Fri, 13 Aug 2010 10:35:15 -0400
Subject: [hwmon] add k10temp sensor driver
Message-id: <20100813103515.4326.2513.stgit@localhost.localdomain>
Patchwork-id: 27555
O-Subject: [RHEL5.6 PATCH 2/3] hwmon: add k10temp sensor driver
Bugzilla: 443745
RH-Acked-by: Ivan Vecera <ivecera@redhat.com>
RH-Acked-by: Dean Nelson <dnelson@redhat.com>
RH-Acked-by: Prarit Bhargava <prarit@redhat.com>
RH-Acked-by: John Feeney <jfeeney@redhat.com>

BZ: https://bugzilla.redhat.com/show_bug.cgi?id=443745

Add support for the temperature sensor in AMD family 10h and 11h CPUs.
By default the driver refuses to work on models affected by AMD erratum #319
("Inaccurate Temperature Measurement").

The module was taken from upstream (v2.6.35).

Brew build:
https://brewweb.devel.redhat.com/taskinfo?taskID=2679164

Testing:
I tested with AMD Phenom(tm) II X6 1090T. The driver provided correct values in
/sys/class/hwmon/hwmon0/device/temp1_*.
Userspace lm_sensors needs a small patch (tracked in bug 623971).

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index c032a8e..2622230 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -165,6 +165,18 @@ config SENSORS_K8TEMP
 	  This driver can also be built as a module.  If so, the module
 	  will be called k8temp.
 
+config SENSORS_K10TEMP
+	tristate "AMD Phenom/Sempron/Turion/Opteron temperature sensor"
+	depends on X86 && PCI
+	help
+	  If you say yes here you get support for the temperature
+	  sensor(s) inside your CPU. Supported are later revisions of
+	  the AMD Family 10h and all revisions of the AMD Family 11h
+	  microarchitectures.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called k10temp.
+
 config SENSORS_AMS
 	tristate "Apple Motion Sensor driver"
 	depends on PPC_PMAC && !PPC64 && INPUT && ((ADB_PMU && I2C = y) || (ADB_PMU && !I2C) || I2C) && EXPERIMENTAL
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 3bdb05a..6b3a5b1 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_SENSORS_I5K_AMB)	+= i5k_amb.o
 obj-$(CONFIG_SENSORS_IBMPEX)	+= ibmpex.o
 obj-$(CONFIG_SENSORS_IT87)	+= it87.o
 obj-$(CONFIG_SENSORS_K8TEMP)	+= k8temp.o
+obj-$(CONFIG_SENSORS_K10TEMP)	+= k10temp.o
 obj-$(CONFIG_SENSORS_LM63)	+= lm63.o
 obj-$(CONFIG_SENSORS_LM70)	+= lm70.o
 obj-$(CONFIG_SENSORS_LM75)	+= lm75.o
diff --git a/drivers/hwmon/k10temp.c b/drivers/hwmon/k10temp.c
new file mode 100644
index 0000000..9a31e58
--- /dev/null
+++ b/drivers/hwmon/k10temp.c
@@ -0,0 +1,233 @@
+/*
+ * 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 int force;
+module_param(force, bool, 0444);
+MODULE_PARM_DESC(force, "force loading on processors with erratum 319");
+
+/* CPUID function 0x80000001, ebx */
+#define CPUID_PKGTYPE_MASK	0xf0000000
+#define CPUID_PKGTYPE_F		0x00000000
+#define CPUID_PKGTYPE_AM2R2_AM3	0x10000000
+
+/* DRAM controller (PCI function 2) */
+#define REG_DCT0_CONFIG_HIGH		0x094
+#define  DDR3_MODE			0x00000100
+
+/* miscellaneous (PCI function 3) */
+#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(struct pci_dev *pdev)
+{
+	u32 pkg_type, reg_dram_cfg;
+
+	if (boot_cpu_data.x86 != 0x10)
+		return false;
+
+	/*
+	 * Erratum 319: The thermal sensor of Socket F/AM2+ processors
+	 *              may be unreliable.
+	 */
+	pkg_type = cpuid_ebx(0x80000001) & CPUID_PKGTYPE_MASK;
+	if (pkg_type == CPUID_PKGTYPE_F)
+		return true;
+	if (pkg_type != CPUID_PKGTYPE_AM2R2_AM3)
+		return false;
+
+	/* DDR3 memory implies socket AM3, which is good */
+	pci_bus_read_config_dword(pdev->bus,
+				  PCI_DEVFN(PCI_SLOT(pdev->devfn), 2),
+				  REG_DCT0_CONFIG_HIGH, &reg_dram_cfg);
+	if (reg_dram_cfg & DDR3_MODE)
+		return false;
+
+	/*
+	 * Unfortunately it is possible to run a socket AM3 CPU with DDR2
+	 * memory. We blacklist all the cores which do exist in socket AM2+
+	 * format. It still isn't perfect, as RB-C2 cores exist in both AM2+
+	 * and AM3 formats, but that's the best we can do.
+	 */
+	return boot_cpu_data.x86_model < 4 ||
+	       (boot_cpu_data.x86_model == 4 && boot_cpu_data.x86_mask <= 2);
+}
+
+static int __devinit k10temp_probe(struct pci_dev *pdev,
+				   const struct pci_device_id *id)
+{
+	struct class_device *hwmon_dev;
+	u32 reg_caps, reg_htc;
+	int unreliable = has_erratum_319(pdev);
+	int err;
+
+	if (unreliable && !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 (unreliable && 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 const 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)