2 * via-cputemp.c - Driver for VIA CPU core temperature monitoring
3 * Copyright (C) 2009 VIA Technologies, Inc.
5 * based on existing coretemp.c, which is
7 * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; version 2 of the License.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
24 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/hwmon.h>
30 #include <linux/hwmon-vid.h>
31 #include <linux/sysfs.h>
32 #include <linux/hwmon-sysfs.h>
33 #include <linux/err.h>
34 #include <linux/mutex.h>
35 #include <linux/list.h>
36 #include <linux/platform_device.h>
37 #include <linux/cpu.h>
39 #include <asm/cpu_device_id.h>
41 #include "../xen/core/domctl.h"
43 #define DRVNAME "via_cputemp"
45 enum { SHOW_TEMP, SHOW_LABEL, SHOW_NAME };
48 * Functions declaration
52 struct list_head list;
53 struct platform_device *pdev;
54 struct device *hwmon_dev;
61 #define via_cputemp_data pdev_entry
67 static ssize_t show_name(struct device *dev, struct device_attribute
71 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
72 struct via_cputemp_data *data = dev_get_drvdata(dev);
74 if (attr->index == SHOW_NAME)
75 ret = sprintf(buf, "%s\n", data->name);
77 ret = sprintf(buf, "Core %d\n", data->pdev->id);
81 static ssize_t show_temp(struct device *dev,
82 struct device_attribute *devattr, char *buf)
84 struct via_cputemp_data *data = dev_get_drvdata(dev);
88 err = rdmsr_safe_on_pcpu(data->pdev->id, data->msr_temp, &eax, &edx);
92 return sprintf(buf, "%lu\n", ((unsigned long)eax & 0xffffff) * 1000);
95 static ssize_t show_cpu_vid(struct device *dev,
96 struct device_attribute *devattr, char *buf)
98 struct via_cputemp_data *data = dev_get_drvdata(dev);
102 err = rdmsr_safe_on_pcpu(data->pdev->id, data->msr_vid, &eax, &edx);
106 return sprintf(buf, "%d\n", vid_from_reg(~edx & 0x7f, data->vrm));
109 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL,
111 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_name, NULL, SHOW_LABEL);
112 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, SHOW_NAME);
114 static struct attribute *via_cputemp_attributes[] = {
115 &sensor_dev_attr_name.dev_attr.attr,
116 &sensor_dev_attr_temp1_label.dev_attr.attr,
117 &sensor_dev_attr_temp1_input.dev_attr.attr,
121 static const struct attribute_group via_cputemp_group = {
122 .attrs = via_cputemp_attributes,
125 /* Optional attributes */
126 static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_cpu_vid, NULL);
128 static int via_cputemp_probe(struct platform_device *pdev)
130 struct via_cputemp_data *data = platform_get_drvdata(pdev);
134 data->name = "via_cputemp";
136 switch (data->x86_model) {
141 data->msr_temp = 0x1169;
142 data->msr_vid = 0x198;
146 data->msr_temp = 0x1423;
152 /* test if we can access the TEMPERATURE MSR */
153 err = rdmsr_safe_on_pcpu(pdev->id, data->msr_temp, &eax, &edx);
156 "Unable to access TEMPERATURE MSR, giving up\n");
160 err = sysfs_create_group(&pdev->dev.kobj, &via_cputemp_group);
165 data->vrm = vid_which_vrm();
168 err = device_create_file(&pdev->dev, &dev_attr_cpu0_vid);
173 data->hwmon_dev = hwmon_device_register(&pdev->dev);
174 if (IS_ERR(data->hwmon_dev)) {
175 err = PTR_ERR(data->hwmon_dev);
176 dev_err(&pdev->dev, "Class registration failed (%d)\n",
185 device_remove_file(&pdev->dev, &dev_attr_cpu0_vid);
186 sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group);
190 static int via_cputemp_remove(struct platform_device *pdev)
192 struct via_cputemp_data *data = platform_get_drvdata(pdev);
194 hwmon_device_unregister(data->hwmon_dev);
196 device_remove_file(&pdev->dev, &dev_attr_cpu0_vid);
197 sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group);
201 static struct platform_driver via_cputemp_driver = {
203 .owner = THIS_MODULE,
206 .probe = via_cputemp_probe,
207 .remove = via_cputemp_remove,
210 static LIST_HEAD(pdev_list);
211 static DEFINE_MUTEX(pdev_list_mutex);
214 struct pdev_entry *pdev_entry;
218 static void get_cpuid_info(void *arg)
220 struct cpu_info *info = arg;
221 struct pdev_entry *pdev_entry = info->pdev_entry;
222 u32 val = cpuid_eax(1);
224 info->x86 = ((val >> 8) & 0xf) + ((val >> 20) & 0xff);
225 pdev_entry->x86_model = ((val >> 4) & 0xf) | ((val >> 12) & 0xf0);
228 static int via_cputemp_device_add(unsigned int cpu)
231 struct cpu_info info;
232 struct platform_device *pdev;
233 struct pdev_entry *pdev_entry;
235 pdev_entry = kzalloc(sizeof(*pdev_entry), GFP_KERNEL);
239 info.pdev_entry = pdev_entry;
240 err = xen_set_physical_cpu_affinity(cpu);
242 get_cpuid_info(&info);
243 WARN_ON_ONCE(xen_set_physical_cpu_affinity(-1));
244 } else if (err > 0) {
249 printk(KERN_WARNING DRVNAME
250 "Cannot set physical CPU affinity"
251 " (assuming use of dom0_vcpus_pin)\n");
253 err = smp_call_function_single(cpu, get_cpuid_info, &info, 1);
256 goto exit_entry_free;
259 goto exit_entry_free;
261 if (pdev_entry->x86_model < 0x0a)
262 goto exit_entry_free;
264 if (pdev_entry->x86_model > 0x0f) {
265 pr_warn("Unknown CPU model 0x%x\n", pdev_entry->x86_model);
266 goto exit_entry_free;
269 pdev = platform_device_alloc(DRVNAME, cpu);
272 pr_err("Device allocation failed\n");
273 goto exit_entry_free;
276 platform_set_drvdata(pdev, pdev_entry);
277 pdev_entry->pdev = pdev;
279 err = platform_device_add(pdev);
281 pr_err("Device addition failed (%d)\n", err);
282 goto exit_device_put;
285 mutex_lock(&pdev_list_mutex);
286 list_add_tail(&pdev_entry->list, &pdev_list);
287 mutex_unlock(&pdev_list_mutex);
292 platform_device_put(pdev);
298 static void via_cputemp_device_remove(unsigned int cpu)
300 struct pdev_entry *p;
302 mutex_lock(&pdev_list_mutex);
303 list_for_each_entry(p, &pdev_list, list) {
304 if (p->pdev->id == cpu) {
305 platform_device_unregister(p->pdev);
307 mutex_unlock(&pdev_list_mutex);
312 mutex_unlock(&pdev_list_mutex);
315 static int via_cputemp_cpu_callback(struct notifier_block *nfb,
316 unsigned long action, void *hcpu)
318 unsigned int cpu = (unsigned long) hcpu;
322 via_cputemp_device_add(cpu);
325 via_cputemp_device_remove(cpu);
331 static struct notifier_block via_cputemp_cpu_notifier = {
332 .notifier_call = via_cputemp_cpu_callback,
335 static const struct x86_cpu_id cputemp_ids[] = {
336 { X86_VENDOR_CENTAUR, 6, 0xa, }, /* C7 A */
337 { X86_VENDOR_CENTAUR, 6, 0xd, }, /* C7 D */
338 { X86_VENDOR_CENTAUR, 6, 0xf, }, /* Nano */
341 MODULE_DEVICE_TABLE(x86cpu, cputemp_ids);
343 static int __init via_cputemp_init(void)
347 if (!is_initial_xendomain())
350 if (!x86_match_cpu(cputemp_ids))
353 err = platform_driver_register(&via_cputemp_driver);
357 err = register_pcpu_notifier(&via_cputemp_cpu_notifier);
359 goto exit_driver_unreg;
361 #ifndef CONFIG_ACPI_HOTPLUG_CPU
362 if (list_empty(&pdev_list)) {
363 unregister_pcpu_notifier(&via_cputemp_cpu_notifier);
365 goto exit_driver_unreg;
372 platform_driver_unregister(&via_cputemp_driver);
377 static void __exit via_cputemp_exit(void)
379 struct pdev_entry *p, *n;
381 unregister_pcpu_notifier(&via_cputemp_cpu_notifier);
382 mutex_lock(&pdev_list_mutex);
383 list_for_each_entry_safe(p, n, &pdev_list, list) {
384 platform_device_unregister(p->pdev);
388 mutex_unlock(&pdev_list_mutex);
389 platform_driver_unregister(&via_cputemp_driver);
392 MODULE_AUTHOR("Harald Welte <HaraldWelte@viatech.com>");
393 MODULE_DESCRIPTION("VIA CPU temperature monitor");
394 MODULE_LICENSE("GPL");
396 module_init(via_cputemp_init)
397 module_exit(via_cputemp_exit)