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-rw-r--r--drivers/hwmon/coretemp.c479
1 files changed, 479 insertions, 0 deletions
diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
new file mode 100644
index 0000000..93c1722
--- /dev/null
+++ b/drivers/hwmon/coretemp.c
@@ -0,0 +1,479 @@
+/*
+ * coretemp.c - Linux kernel module for hardware monitoring
+ *
+ * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
+ *
+ * Inspired from many hwmon 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; 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.
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/hwmon.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>
+
+#define DRVNAME "coretemp"
+
+typedef enum { SHOW_TEMP, SHOW_TJMAX, SHOW_TTARGET, SHOW_LABEL,
+ SHOW_NAME } SHOW;
+
+/*
+ * Functions declaration
+ */
+
+static struct coretemp_data *coretemp_update_device(struct device *dev);
+
+struct coretemp_data {
+ struct device *hwmon_dev;
+ struct mutex update_lock;
+ const char *name;
+ u32 id;
+ char valid; /* zero until following fields are valid */
+ unsigned long last_updated; /* in jiffies */
+ int temp;
+ int tjmax;
+ int ttarget;
+ u8 alarm;
+};
+
+/*
+ * 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 coretemp_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_alarm(struct device *dev, struct device_attribute
+ *devattr, char *buf)
+{
+ struct coretemp_data *data = coretemp_update_device(dev);
+ /* read the Out-of-spec log, never clear */
+ return sprintf(buf, "%d\n", data->alarm);
+}
+
+static ssize_t show_temp(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ struct coretemp_data *data = coretemp_update_device(dev);
+ int err;
+
+ if (attr->index == SHOW_TEMP)
+ err = data->valid ? sprintf(buf, "%d\n", data->temp) : -EAGAIN;
+ else if (attr->index == SHOW_TJMAX)
+ err = sprintf(buf, "%d\n", data->tjmax);
+ else
+ err = sprintf(buf, "%d\n", data->ttarget);
+ return err;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL,
+ SHOW_TEMP);
+static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL,
+ SHOW_TJMAX);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL,
+ SHOW_TTARGET);
+static DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL);
+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 *coretemp_attributes[] = {
+ &sensor_dev_attr_name.dev_attr.attr,
+ &sensor_dev_attr_temp1_label.dev_attr.attr,
+ &dev_attr_temp1_crit_alarm.attr,
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_temp1_crit.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group coretemp_group = {
+ .attrs = coretemp_attributes,
+};
+
+static struct coretemp_data *coretemp_update_device(struct device *dev)
+{
+ struct coretemp_data *data = dev_get_drvdata(dev);
+
+ mutex_lock(&data->update_lock);
+
+ if (!data->valid || time_after(jiffies, data->last_updated + HZ)) {
+ u32 eax, edx;
+
+ data->valid = 0;
+ rdmsr_on_cpu(data->id, MSR_IA32_THERM_STATUS, &eax, &edx);
+ data->alarm = (eax >> 5) & 1;
+ /* update only if data has been valid */
+ if (eax & 0x80000000) {
+ data->temp = data->tjmax - (((eax >> 16)
+ & 0x7f) * 1000);
+ data->valid = 1;
+ } else {
+ dev_dbg(dev, "Temperature data invalid (0x%x)\n", eax);
+ }
+ data->last_updated = jiffies;
+ }
+
+ mutex_unlock(&data->update_lock);
+ return data;
+}
+
+static int __devinit adjust_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev)
+{
+ /* The 100C is default for both mobile and non mobile CPUs */
+
+ int tjmax = 100000;
+ int ismobile = 1;
+ int err;
+ u32 eax, edx;
+
+ /* Early chips have no MSR for TjMax */
+
+ if ((c->x86_model == 0xf) && (c->x86_mask < 4)) {
+ ismobile = 0;
+ }
+
+ if ((c->x86_model > 0xe) && (ismobile)) {
+
+ /* Now we can detect the mobile CPU using Intel provided table
+ http://softwarecommunity.intel.com/Wiki/Mobility/720.htm
+ For Core2 cores, check MSR 0x17, bit 28 1 = Mobile CPU
+ */
+
+ err = rdmsr_safe_on_cpu(id, 0x17, &eax, &edx);
+ if (err) {
+ dev_warn(dev,
+ "Unable to access MSR 0x17, assuming desktop"
+ " CPU\n");
+ ismobile = 0;
+ } else if (!(eax & 0x10000000)) {
+ ismobile = 0;
+ }
+ }
+
+ if (ismobile) {
+
+ err = rdmsr_safe_on_cpu(id, 0xee, &eax, &edx);
+ if (err) {
+ dev_warn(dev,
+ "Unable to access MSR 0xEE, for Tjmax, left"
+ " at default");
+ } else if (eax & 0x40000000) {
+ tjmax = 85000;
+ }
+ } else {
+ dev_warn(dev, "Using relative temperature scale!\n");
+ }
+
+ return tjmax;
+}
+
+static int __devinit coretemp_probe(struct platform_device *pdev)
+{
+ struct coretemp_data *data;
+ struct cpuinfo_x86 *c = &cpu_data(pdev->id);
+ int err;
+ u32 eax, edx;
+
+ if (!(data = kzalloc(sizeof(struct coretemp_data), GFP_KERNEL))) {
+ err = -ENOMEM;
+ dev_err(&pdev->dev, "Out of memory\n");
+ goto exit;
+ }
+
+ data->id = pdev->id;
+ data->name = "coretemp";
+ mutex_init(&data->update_lock);
+
+ /* test if we can access the THERM_STATUS MSR */
+ err = rdmsr_safe_on_cpu(data->id, MSR_IA32_THERM_STATUS, &eax, &edx);
+ if (err) {
+ dev_err(&pdev->dev,
+ "Unable to access THERM_STATUS MSR, giving up\n");
+ goto exit_free;
+ }
+
+ /* Check if we have problem with errata AE18 of Core processors:
+ Readings might stop update when processor visited too deep sleep,
+ fixed for stepping D0 (6EC).
+ */
+
+ if ((c->x86_model == 0xe) && (c->x86_mask < 0xc)) {
+ /* check for microcode update */
+ rdmsr_on_cpu(data->id, MSR_IA32_UCODE_REV, &eax, &edx);
+ if (edx < 0x39) {
+ err = -ENODEV;
+ dev_err(&pdev->dev,
+ "Errata AE18 not fixed, update BIOS or "
+ "microcode of the CPU!\n");
+ goto exit_free;
+ }
+ }
+
+ data->tjmax = adjust_tjmax(c, data->id, &pdev->dev);
+ platform_set_drvdata(pdev, data);
+
+ /* read the still undocumented IA32_TEMPERATURE_TARGET it exists
+ on older CPUs but not in this register */
+
+ if (c->x86_model > 0xe) {
+ err = rdmsr_safe_on_cpu(data->id, 0x1a2, &eax, &edx);
+ if (err) {
+ dev_warn(&pdev->dev, "Unable to read"
+ " IA32_TEMPERATURE_TARGET MSR\n");
+ } else {
+ data->ttarget = data->tjmax -
+ (((eax >> 8) & 0xff) * 1000);
+ err = device_create_file(&pdev->dev,
+ &sensor_dev_attr_temp1_max.dev_attr);
+ if (err)
+ goto exit_free;
+ }
+ }
+
+ if ((err = sysfs_create_group(&pdev->dev.kobj, &coretemp_group)))
+ goto exit_dev;
+
+ 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_class;
+ }
+
+ return 0;
+
+exit_class:
+ sysfs_remove_group(&pdev->dev.kobj, &coretemp_group);
+exit_dev:
+ device_remove_file(&pdev->dev, &sensor_dev_attr_temp1_max.dev_attr);
+exit_free:
+ kfree(data);
+exit:
+ return err;
+}
+
+static int __devexit coretemp_remove(struct platform_device *pdev)
+{
+ struct coretemp_data *data = platform_get_drvdata(pdev);
+
+ hwmon_device_unregister(data->hwmon_dev);
+ sysfs_remove_group(&pdev->dev.kobj, &coretemp_group);
+ device_remove_file(&pdev->dev, &sensor_dev_attr_temp1_max.dev_attr);
+ platform_set_drvdata(pdev, NULL);
+ kfree(data);
+ return 0;
+}
+
+static struct platform_driver coretemp_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = DRVNAME,
+ },
+ .probe = coretemp_probe,
+ .remove = __devexit_p(coretemp_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 __cpuinit coretemp_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;
+ printk(KERN_ERR DRVNAME ": 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) {
+ printk(KERN_ERR DRVNAME ": 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;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static void coretemp_device_remove(unsigned int cpu)
+{
+ struct pdev_entry *p, *n;
+ mutex_lock(&pdev_list_mutex);
+ list_for_each_entry_safe(p, n, &pdev_list, list) {
+ if (p->cpu == cpu) {
+ platform_device_unregister(p->pdev);
+ list_del(&p->list);
+ kfree(p);
+ }
+ }
+ mutex_unlock(&pdev_list_mutex);
+}
+
+static int __cpuinit coretemp_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:
+ coretemp_device_add(cpu);
+ break;
+ case CPU_DOWN_PREPARE:
+ coretemp_device_remove(cpu);
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block coretemp_cpu_notifier __refdata = {
+ .notifier_call = coretemp_cpu_callback,
+};
+#endif /* !CONFIG_HOTPLUG_CPU */
+
+static int __init coretemp_init(void)
+{
+ int i, err = -ENODEV;
+ struct pdev_entry *p, *n;
+
+ /* quick check if we run Intel */
+ if (cpu_data(0).x86_vendor != X86_VENDOR_INTEL)
+ goto exit;
+
+ err = platform_driver_register(&coretemp_driver);
+ if (err)
+ goto exit;
+
+ for_each_online_cpu(i) {
+ struct cpuinfo_x86 *c = &cpu_data(i);
+
+ /* check if family 6, models 0xe, 0xf, 0x16, 0x17, 0x1A */
+ if ((c->cpuid_level < 0) || (c->x86 != 0x6) ||
+ !((c->x86_model == 0xe) || (c->x86_model == 0xf) ||
+ (c->x86_model == 0x16) || (c->x86_model == 0x17) ||
+ (c->x86_model == 0x1A))) {
+
+ /* supported CPU not found, but report the unknown
+ family 6 CPU */
+ if ((c->x86 == 0x6) && (c->x86_model > 0xf))
+ printk(KERN_WARNING DRVNAME ": Unknown CPU "
+ "model %x\n", c->x86_model);
+ continue;
+ }
+
+ err = coretemp_device_add(i);
+ if (err)
+ goto exit_devices_unreg;
+ }
+ if (list_empty(&pdev_list)) {
+ err = -ENODEV;
+ goto exit_driver_unreg;
+ }
+
+#ifdef CONFIG_HOTPLUG_CPU
+ register_hotcpu_notifier(&coretemp_cpu_notifier);
+#endif
+ return 0;
+
+exit_devices_unreg:
+ 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);
+exit_driver_unreg:
+ platform_driver_unregister(&coretemp_driver);
+exit:
+ return err;
+}
+
+static void __exit coretemp_exit(void)
+{
+ struct pdev_entry *p, *n;
+#ifdef CONFIG_HOTPLUG_CPU
+ unregister_hotcpu_notifier(&coretemp_cpu_notifier);
+#endif
+ 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);
+ platform_driver_unregister(&coretemp_driver);
+}
+
+MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
+MODULE_DESCRIPTION("Intel Core temperature monitor");
+MODULE_LICENSE("GPL");
+
+module_init(coretemp_init)
+module_exit(coretemp_exit)
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