2 * coretemp.c - Linux kernel module for hardware monitoring
4 * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
6 * Inspired from many hwmon drivers
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; version 2 of the License.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
23 #include <linux/module.h>
24 #include <linux/delay.h>
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <linux/jiffies.h>
28 #include <linux/hwmon.h>
29 #include <linux/sysfs.h>
30 #include <linux/hwmon-sysfs.h>
31 #include <linux/err.h>
32 #include <linux/mutex.h>
33 #include <linux/list.h>
34 #include <linux/platform_device.h>
35 #include <linux/cpu.h>
36 #include <linux/pci.h>
38 #include <asm/processor.h>
40 #define DRVNAME "coretemp"
42 typedef enum { SHOW_TEMP
, SHOW_TJMAX
, SHOW_TTARGET
, SHOW_LABEL
,
46 * Functions declaration
49 static struct coretemp_data
*coretemp_update_device(struct device
*dev
);
51 struct coretemp_data
{
52 struct device
*hwmon_dev
;
53 struct mutex update_lock
;
56 char valid
; /* zero until following fields are valid */
57 unsigned long last_updated
; /* in jiffies */
68 static ssize_t
show_name(struct device
*dev
, struct device_attribute
72 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(devattr
);
73 struct coretemp_data
*data
= dev_get_drvdata(dev
);
75 if (attr
->index
== SHOW_NAME
)
76 ret
= sprintf(buf
, "%s\n", data
->name
);
78 ret
= sprintf(buf
, "Core %d\n", data
->id
);
82 static ssize_t
show_alarm(struct device
*dev
, struct device_attribute
85 struct coretemp_data
*data
= coretemp_update_device(dev
);
86 /* read the Out-of-spec log, never clear */
87 return sprintf(buf
, "%d\n", data
->alarm
);
90 static ssize_t
show_temp(struct device
*dev
,
91 struct device_attribute
*devattr
, char *buf
)
93 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(devattr
);
94 struct coretemp_data
*data
= coretemp_update_device(dev
);
97 if (attr
->index
== SHOW_TEMP
)
98 err
= data
->valid
? sprintf(buf
, "%d\n", data
->temp
) : -EAGAIN
;
99 else if (attr
->index
== SHOW_TJMAX
)
100 err
= sprintf(buf
, "%d\n", data
->tjmax
);
102 err
= sprintf(buf
, "%d\n", data
->ttarget
);
106 static SENSOR_DEVICE_ATTR(temp1_input
, S_IRUGO
, show_temp
, NULL
,
108 static SENSOR_DEVICE_ATTR(temp1_crit
, S_IRUGO
, show_temp
, NULL
,
110 static SENSOR_DEVICE_ATTR(temp1_max
, S_IRUGO
, show_temp
, NULL
,
112 static DEVICE_ATTR(temp1_crit_alarm
, S_IRUGO
, show_alarm
, NULL
);
113 static SENSOR_DEVICE_ATTR(temp1_label
, S_IRUGO
, show_name
, NULL
, SHOW_LABEL
);
114 static SENSOR_DEVICE_ATTR(name
, S_IRUGO
, show_name
, NULL
, SHOW_NAME
);
116 static struct attribute
*coretemp_attributes
[] = {
117 &sensor_dev_attr_name
.dev_attr
.attr
,
118 &sensor_dev_attr_temp1_label
.dev_attr
.attr
,
119 &dev_attr_temp1_crit_alarm
.attr
,
120 &sensor_dev_attr_temp1_input
.dev_attr
.attr
,
121 &sensor_dev_attr_temp1_crit
.dev_attr
.attr
,
125 static const struct attribute_group coretemp_group
= {
126 .attrs
= coretemp_attributes
,
129 static struct coretemp_data
*coretemp_update_device(struct device
*dev
)
131 struct coretemp_data
*data
= dev_get_drvdata(dev
);
133 mutex_lock(&data
->update_lock
);
135 if (!data
->valid
|| time_after(jiffies
, data
->last_updated
+ HZ
)) {
139 rdmsr_on_cpu(data
->id
, MSR_IA32_THERM_STATUS
, &eax
, &edx
);
140 data
->alarm
= (eax
>> 5) & 1;
141 /* update only if data has been valid */
142 if (eax
& 0x80000000) {
143 data
->temp
= data
->tjmax
- (((eax
>> 16)
147 dev_dbg(dev
, "Temperature data invalid (0x%x)\n", eax
);
149 data
->last_updated
= jiffies
;
152 mutex_unlock(&data
->update_lock
);
156 static int __devinit
adjust_tjmax(struct cpuinfo_x86
*c
, u32 id
, struct device
*dev
)
158 /* The 100C is default for both mobile and non mobile CPUs */
161 int tjmax_ee
= 85000;
165 struct pci_dev
*host_bridge
;
167 /* Early chips have no MSR for TjMax */
169 if ((c
->x86_model
== 0xf) && (c
->x86_mask
< 4)) {
175 if (c
->x86_model
== 0x1c) {
178 host_bridge
= pci_get_bus_and_slot(0, PCI_DEVFN(0, 0));
180 if (host_bridge
&& host_bridge
->vendor
== PCI_VENDOR_ID_INTEL
181 && (host_bridge
->device
== 0xa000 /* NM10 based nettop */
182 || host_bridge
->device
== 0xa010)) /* NM10 based netbook */
187 pci_dev_put(host_bridge
);
190 if ((c
->x86_model
> 0xe) && (usemsr_ee
)) {
193 /* Now we can detect the mobile CPU using Intel provided table
194 http://softwarecommunity.intel.com/Wiki/Mobility/720.htm
195 For Core2 cores, check MSR 0x17, bit 28 1 = Mobile CPU
198 err
= rdmsr_safe_on_cpu(id
, 0x17, &eax
, &edx
);
201 "Unable to access MSR 0x17, assuming desktop"
204 } else if (c
->x86_model
< 0x17 && !(eax
& 0x10000000)) {
205 /* Trust bit 28 up to Penryn, I could not find any
206 documentation on that; if you happen to know
207 someone at Intel please ask */
210 /* Platform ID bits 52:50 (EDX starts at bit 32) */
211 platform_id
= (edx
>> 18) & 0x7;
213 /* Mobile Penryn CPU seems to be platform ID 7 or 5
215 if ((c
->x86_model
== 0x17) &&
216 ((platform_id
== 5) || (platform_id
== 7))) {
217 /* If MSR EE bit is set, set it to 90 degrees C,
218 otherwise 105 degrees C */
227 err
= rdmsr_safe_on_cpu(id
, 0xee, &eax
, &edx
);
230 "Unable to access MSR 0xEE, for Tjmax, left"
232 } else if (eax
& 0x40000000) {
235 /* if we dont use msr EE it means we are desktop CPU (with exeception
237 } else if (tjmax
== 100000) {
238 dev_warn(dev
, "Using relative temperature scale!\n");
244 static int __devinit
coretemp_probe(struct platform_device
*pdev
)
246 struct coretemp_data
*data
;
247 struct cpuinfo_x86
*c
= &cpu_data(pdev
->id
);
251 if (!(data
= kzalloc(sizeof(struct coretemp_data
), GFP_KERNEL
))) {
253 dev_err(&pdev
->dev
, "Out of memory\n");
258 data
->name
= "coretemp";
259 mutex_init(&data
->update_lock
);
261 /* test if we can access the THERM_STATUS MSR */
262 err
= rdmsr_safe_on_cpu(data
->id
, MSR_IA32_THERM_STATUS
, &eax
, &edx
);
265 "Unable to access THERM_STATUS MSR, giving up\n");
269 /* Check if we have problem with errata AE18 of Core processors:
270 Readings might stop update when processor visited too deep sleep,
271 fixed for stepping D0 (6EC).
274 if ((c
->x86_model
== 0xe) && (c
->x86_mask
< 0xc)) {
275 /* check for microcode update */
276 rdmsr_on_cpu(data
->id
, MSR_IA32_UCODE_REV
, &eax
, &edx
);
280 "Errata AE18 not fixed, update BIOS or "
281 "microcode of the CPU!\n");
286 data
->tjmax
= adjust_tjmax(c
, data
->id
, &pdev
->dev
);
287 platform_set_drvdata(pdev
, data
);
289 /* read the still undocumented IA32_TEMPERATURE_TARGET it exists
290 on older CPUs but not in this register, Atoms don't have it either */
292 if ((c
->x86_model
> 0xe) && (c
->x86_model
!= 0x1c)) {
293 err
= rdmsr_safe_on_cpu(data
->id
, 0x1a2, &eax
, &edx
);
295 dev_warn(&pdev
->dev
, "Unable to read"
296 " IA32_TEMPERATURE_TARGET MSR\n");
298 data
->ttarget
= data
->tjmax
-
299 (((eax
>> 8) & 0xff) * 1000);
300 err
= device_create_file(&pdev
->dev
,
301 &sensor_dev_attr_temp1_max
.dev_attr
);
307 if ((err
= sysfs_create_group(&pdev
->dev
.kobj
, &coretemp_group
)))
310 data
->hwmon_dev
= hwmon_device_register(&pdev
->dev
);
311 if (IS_ERR(data
->hwmon_dev
)) {
312 err
= PTR_ERR(data
->hwmon_dev
);
313 dev_err(&pdev
->dev
, "Class registration failed (%d)\n",
321 sysfs_remove_group(&pdev
->dev
.kobj
, &coretemp_group
);
323 device_remove_file(&pdev
->dev
, &sensor_dev_attr_temp1_max
.dev_attr
);
330 static int __devexit
coretemp_remove(struct platform_device
*pdev
)
332 struct coretemp_data
*data
= platform_get_drvdata(pdev
);
334 hwmon_device_unregister(data
->hwmon_dev
);
335 sysfs_remove_group(&pdev
->dev
.kobj
, &coretemp_group
);
336 device_remove_file(&pdev
->dev
, &sensor_dev_attr_temp1_max
.dev_attr
);
337 platform_set_drvdata(pdev
, NULL
);
342 static struct platform_driver coretemp_driver
= {
344 .owner
= THIS_MODULE
,
347 .probe
= coretemp_probe
,
348 .remove
= __devexit_p(coretemp_remove
),
352 struct list_head list
;
353 struct platform_device
*pdev
;
357 static LIST_HEAD(pdev_list
);
358 static DEFINE_MUTEX(pdev_list_mutex
);
360 static int __cpuinit
coretemp_device_add(unsigned int cpu
)
363 struct platform_device
*pdev
;
364 struct pdev_entry
*pdev_entry
;
366 pdev
= platform_device_alloc(DRVNAME
, cpu
);
369 printk(KERN_ERR DRVNAME
": Device allocation failed\n");
373 pdev_entry
= kzalloc(sizeof(struct pdev_entry
), GFP_KERNEL
);
376 goto exit_device_put
;
379 err
= platform_device_add(pdev
);
381 printk(KERN_ERR DRVNAME
": Device addition failed (%d)\n",
383 goto exit_device_free
;
386 pdev_entry
->pdev
= pdev
;
387 pdev_entry
->cpu
= cpu
;
388 mutex_lock(&pdev_list_mutex
);
389 list_add_tail(&pdev_entry
->list
, &pdev_list
);
390 mutex_unlock(&pdev_list_mutex
);
397 platform_device_put(pdev
);
402 #ifdef CONFIG_HOTPLUG_CPU
403 static void coretemp_device_remove(unsigned int cpu
)
405 struct pdev_entry
*p
, *n
;
406 mutex_lock(&pdev_list_mutex
);
407 list_for_each_entry_safe(p
, n
, &pdev_list
, list
) {
409 platform_device_unregister(p
->pdev
);
414 mutex_unlock(&pdev_list_mutex
);
417 static int __cpuinit
coretemp_cpu_callback(struct notifier_block
*nfb
,
418 unsigned long action
, void *hcpu
)
420 unsigned int cpu
= (unsigned long) hcpu
;
424 case CPU_DOWN_FAILED
:
425 coretemp_device_add(cpu
);
427 case CPU_DOWN_PREPARE
:
428 coretemp_device_remove(cpu
);
434 static struct notifier_block coretemp_cpu_notifier __refdata
= {
435 .notifier_call
= coretemp_cpu_callback
,
437 #endif /* !CONFIG_HOTPLUG_CPU */
439 static int __init
coretemp_init(void)
441 int i
, err
= -ENODEV
;
442 struct pdev_entry
*p
, *n
;
444 /* quick check if we run Intel */
445 if (cpu_data(0).x86_vendor
!= X86_VENDOR_INTEL
)
448 err
= platform_driver_register(&coretemp_driver
);
452 for_each_online_cpu(i
) {
453 struct cpuinfo_x86
*c
= &cpu_data(i
);
455 /* check if family 6, models 0xe (Pentium M DC),
456 0xf (Core 2 DC 65nm), 0x16 (Core 2 SC 65nm),
457 0x17 (Penryn 45nm), 0x1a (Nehalem), 0x1c (Atom),
459 if ((c
->cpuid_level
< 0) || (c
->x86
!= 0x6) ||
460 !((c
->x86_model
== 0xe) || (c
->x86_model
== 0xf) ||
461 (c
->x86_model
== 0x16) || (c
->x86_model
== 0x17) ||
462 (c
->x86_model
== 0x1a) || (c
->x86_model
== 0x1c) ||
463 (c
->x86_model
== 0x1e))) {
465 /* supported CPU not found, but report the unknown
467 if ((c
->x86
== 0x6) && (c
->x86_model
> 0xf))
468 printk(KERN_WARNING DRVNAME
": Unknown CPU "
469 "model 0x%x\n", c
->x86_model
);
473 err
= coretemp_device_add(i
);
475 goto exit_devices_unreg
;
477 if (list_empty(&pdev_list
)) {
479 goto exit_driver_unreg
;
482 #ifdef CONFIG_HOTPLUG_CPU
483 register_hotcpu_notifier(&coretemp_cpu_notifier
);
488 mutex_lock(&pdev_list_mutex
);
489 list_for_each_entry_safe(p
, n
, &pdev_list
, list
) {
490 platform_device_unregister(p
->pdev
);
494 mutex_unlock(&pdev_list_mutex
);
496 platform_driver_unregister(&coretemp_driver
);
501 static void __exit
coretemp_exit(void)
503 struct pdev_entry
*p
, *n
;
504 #ifdef CONFIG_HOTPLUG_CPU
505 unregister_hotcpu_notifier(&coretemp_cpu_notifier
);
507 mutex_lock(&pdev_list_mutex
);
508 list_for_each_entry_safe(p
, n
, &pdev_list
, list
) {
509 platform_device_unregister(p
->pdev
);
513 mutex_unlock(&pdev_list_mutex
);
514 platform_driver_unregister(&coretemp_driver
);
517 MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
518 MODULE_DESCRIPTION("Intel Core temperature monitor");
519 MODULE_LICENSE("GPL");
521 module_init(coretemp_init
)
522 module_exit(coretemp_exit
)