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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/slab.h>
28 #include <linux/jiffies.h>
29 #include <linux/hwmon.h>
30 #include <linux/sysfs.h>
31 #include <linux/hwmon-sysfs.h>
32 #include <linux/err.h>
33 #include <linux/mutex.h>
34 #include <linux/list.h>
35 #include <linux/platform_device.h>
36 #include <linux/cpu.h>
37 #include <linux/pci.h>
38 #include <linux/smp.h>
40 #include <asm/processor.h>
42 #define DRVNAME "coretemp"
44 #define BASE_SYSFS_ATTR_NO 2 /* Sysfs Base attr no for coretemp */
45 #define NUM_REAL_CORES 16 /* Number of Real cores per cpu */
46 #define CORETEMP_NAME_LENGTH 17 /* String Length of attrs */
47 #define MAX_CORE_ATTRS 4 /* Maximum no of basic attrs */
48 #define MAX_THRESH_ATTRS 3 /* Maximum no of Threshold attrs */
49 #define TOTAL_ATTRS (MAX_CORE_ATTRS + MAX_THRESH_ATTRS)
50 #define MAX_CORE_DATA (NUM_REAL_CORES + BASE_SYSFS_ATTR_NO)
53 #define TO_PHYS_ID(cpu) cpu_data(cpu).phys_proc_id
54 #define TO_CORE_ID(cpu) cpu_data(cpu).cpu_core_id
55 #define TO_ATTR_NO(cpu) (TO_CORE_ID(cpu) + BASE_SYSFS_ATTR_NO)
56 #define for_each_sibling(i, cpu) for_each_cpu(i, cpu_sibling_mask(cpu))
58 #define TO_PHYS_ID(cpu) (cpu)
59 #define TO_CORE_ID(cpu) (cpu)
60 #define TO_ATTR_NO(cpu) (cpu)
61 #define for_each_sibling(i, cpu) for (i = 0; false; )
65 * Per-Core Temperature Data
66 * @last_updated: The time when the current temperature value was updated
67 * earlier (in jiffies).
68 * @cpu_core_id: The CPU Core from which temperature values should be read
69 * This value is passed as "id" field to rdmsr/wrmsr functions.
70 * @status_reg: One of IA32_THERM_STATUS or IA32_PACKAGE_THERM_STATUS,
71 * from where the temperature values should be read.
72 * @intrpt_reg: One of IA32_THERM_INTERRUPT or IA32_PACKAGE_THERM_INTERRUPT,
73 * from where the thresholds are read.
74 * @attr_size: Total number of pre-core attrs displayed in the sysfs.
75 * @is_pkg_data: If this is 1, the temp_data holds pkgtemp data.
76 * Otherwise, temp_data holds coretemp data.
77 * @valid: If this is 1, the current temperature is valid.
84 unsigned long last_updated;
92 struct sensor_device_attribute sd_attrs[TOTAL_ATTRS];
93 char attr_name[TOTAL_ATTRS][CORETEMP_NAME_LENGTH];
94 struct mutex update_lock;
97 /* Platform Data per Physical CPU */
98 struct platform_data {
99 struct device *hwmon_dev;
101 struct temp_data *core_data[MAX_CORE_DATA];
102 struct device_attribute name_attr;
106 struct list_head list;
107 struct platform_device *pdev;
111 static LIST_HEAD(pdev_list);
112 static DEFINE_MUTEX(pdev_list_mutex);
114 static ssize_t show_name(struct device *dev,
115 struct device_attribute *devattr, char *buf)
117 return sprintf(buf, "%s\n", DRVNAME);
120 static ssize_t show_label(struct device *dev,
121 struct device_attribute *devattr, char *buf)
123 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
124 struct platform_data *pdata = dev_get_drvdata(dev);
125 struct temp_data *tdata = pdata->core_data[attr->index];
127 if (tdata->is_pkg_data)
128 return sprintf(buf, "Physical id %u\n", pdata->phys_proc_id);
130 return sprintf(buf, "Core %u\n", tdata->cpu_core_id);
133 static ssize_t show_crit_alarm(struct device *dev,
134 struct device_attribute *devattr, char *buf)
137 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
138 struct platform_data *pdata = dev_get_drvdata(dev);
139 struct temp_data *tdata = pdata->core_data[attr->index];
141 rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
143 return sprintf(buf, "%d\n", (eax >> 5) & 1);
146 static ssize_t show_max_alarm(struct device *dev,
147 struct device_attribute *devattr, char *buf)
150 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
151 struct platform_data *pdata = dev_get_drvdata(dev);
152 struct temp_data *tdata = pdata->core_data[attr->index];
154 rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
156 return sprintf(buf, "%d\n", !!(eax & THERM_STATUS_THRESHOLD1));
159 static ssize_t show_tjmax(struct device *dev,
160 struct device_attribute *devattr, char *buf)
162 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
163 struct platform_data *pdata = dev_get_drvdata(dev);
165 return sprintf(buf, "%d\n", pdata->core_data[attr->index]->tjmax);
168 static ssize_t show_ttarget(struct device *dev,
169 struct device_attribute *devattr, char *buf)
171 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
172 struct platform_data *pdata = dev_get_drvdata(dev);
174 return sprintf(buf, "%d\n", pdata->core_data[attr->index]->ttarget);
177 static ssize_t store_ttarget(struct device *dev,
178 struct device_attribute *devattr,
179 const char *buf, size_t count)
181 struct platform_data *pdata = dev_get_drvdata(dev);
182 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
183 struct temp_data *tdata = pdata->core_data[attr->index];
188 if (strict_strtoul(buf, 10, &val))
192 * THERM_MASK_THRESHOLD1 is 7 bits wide. Values are entered in terms
193 * of milli degree celsius. Hence don't accept val > (127 * 1000)
195 if (val > tdata->tjmax || val > 127000)
198 diff = (tdata->tjmax - val) / 1000;
200 mutex_lock(&tdata->update_lock);
201 rdmsr_on_cpu(tdata->cpu, tdata->intrpt_reg, &eax, &edx);
202 eax = (eax & ~THERM_MASK_THRESHOLD1) |
203 (diff << THERM_SHIFT_THRESHOLD1);
204 wrmsr_on_cpu(tdata->cpu, tdata->intrpt_reg, eax, edx);
205 tdata->ttarget = val;
206 mutex_unlock(&tdata->update_lock);
211 static ssize_t show_tmin(struct device *dev,
212 struct device_attribute *devattr, char *buf)
214 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
215 struct platform_data *pdata = dev_get_drvdata(dev);
217 return sprintf(buf, "%d\n", pdata->core_data[attr->index]->tmin);
220 static ssize_t store_tmin(struct device *dev,
221 struct device_attribute *devattr,
222 const char *buf, size_t count)
224 struct platform_data *pdata = dev_get_drvdata(dev);
225 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
226 struct temp_data *tdata = pdata->core_data[attr->index];
231 if (strict_strtoul(buf, 10, &val))
235 * THERM_MASK_THRESHOLD0 is 7 bits wide. Values are entered in terms
236 * of milli degree celsius. Hence don't accept val > (127 * 1000)
238 if (val > tdata->tjmax || val > 127000)
241 diff = (tdata->tjmax - val) / 1000;
243 mutex_lock(&tdata->update_lock);
244 rdmsr_on_cpu(tdata->cpu, tdata->intrpt_reg, &eax, &edx);
245 eax = (eax & ~THERM_MASK_THRESHOLD0) |
246 (diff << THERM_SHIFT_THRESHOLD0);
247 wrmsr_on_cpu(tdata->cpu, tdata->intrpt_reg, eax, edx);
249 mutex_unlock(&tdata->update_lock);
254 static ssize_t show_temp(struct device *dev,
255 struct device_attribute *devattr, char *buf)
258 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
259 struct platform_data *pdata = dev_get_drvdata(dev);
260 struct temp_data *tdata = pdata->core_data[attr->index];
262 mutex_lock(&tdata->update_lock);
264 /* Check whether the time interval has elapsed */
265 if (!tdata->valid || time_after(jiffies, tdata->last_updated + HZ)) {
266 rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
268 /* Check whether the data is valid */
269 if (eax & 0x80000000) {
270 tdata->temp = tdata->tjmax -
271 ((eax >> 16) & 0x7f) * 1000;
274 tdata->last_updated = jiffies;
277 mutex_unlock(&tdata->update_lock);
278 return tdata->valid ? sprintf(buf, "%d\n", tdata->temp) : -EAGAIN;
281 static int adjust_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev)
283 /* The 100C is default for both mobile and non mobile CPUs */
286 int tjmax_ee = 85000;
290 struct pci_dev *host_bridge;
292 /* Early chips have no MSR for TjMax */
294 if (c->x86_model == 0xf && c->x86_mask < 4)
299 if (c->x86_model == 0x1c) {
302 host_bridge = pci_get_bus_and_slot(0, PCI_DEVFN(0, 0));
304 if (host_bridge && host_bridge->vendor == PCI_VENDOR_ID_INTEL
305 && (host_bridge->device == 0xa000 /* NM10 based nettop */
306 || host_bridge->device == 0xa010)) /* NM10 based netbook */
311 pci_dev_put(host_bridge);
314 if (c->x86_model > 0xe && usemsr_ee) {
318 * Now we can detect the mobile CPU using Intel provided table
319 * http://softwarecommunity.intel.com/Wiki/Mobility/720.htm
320 * For Core2 cores, check MSR 0x17, bit 28 1 = Mobile CPU
322 err = rdmsr_safe_on_cpu(id, 0x17, &eax, &edx);
325 "Unable to access MSR 0x17, assuming desktop"
328 } else if (c->x86_model < 0x17 && !(eax & 0x10000000)) {
330 * Trust bit 28 up to Penryn, I could not find any
331 * documentation on that; if you happen to know
332 * someone at Intel please ask
336 /* Platform ID bits 52:50 (EDX starts at bit 32) */
337 platform_id = (edx >> 18) & 0x7;
340 * Mobile Penryn CPU seems to be platform ID 7 or 5
343 if (c->x86_model == 0x17 &&
344 (platform_id == 5 || platform_id == 7)) {
346 * If MSR EE bit is set, set it to 90 degrees C,
347 * otherwise 105 degrees C
356 err = rdmsr_safe_on_cpu(id, 0xee, &eax, &edx);
359 "Unable to access MSR 0xEE, for Tjmax, left"
361 } else if (eax & 0x40000000) {
364 } else if (tjmax == 100000) {
366 * If we don't use msr EE it means we are desktop CPU
367 * (with exeception of Atom)
369 dev_warn(dev, "Using relative temperature scale!\n");
375 static int get_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev)
377 /* The 100C is default for both mobile and non mobile CPUs */
383 * A new feature of current Intel(R) processors, the
384 * IA32_TEMPERATURE_TARGET contains the TjMax value
386 err = rdmsr_safe_on_cpu(id, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
388 dev_warn(dev, "Unable to read TjMax from CPU.\n");
390 val = (eax >> 16) & 0xff;
392 * If the TjMax is not plausible, an assumption
396 dev_info(dev, "TjMax is %d C.\n", val);
402 * An assumption is made for early CPUs and unreadable MSR.
403 * NOTE: the calculated value may not be correct.
405 return adjust_tjmax(c, id, dev);
408 static void __devinit get_ucode_rev_on_cpu(void *edx)
412 wrmsr(MSR_IA32_UCODE_REV, 0, 0);
414 rdmsr(MSR_IA32_UCODE_REV, eax, *(u32 *)edx);
417 static int get_pkg_tjmax(unsigned int cpu, struct device *dev)
422 err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
424 val = (eax >> 16) & 0xff;
428 dev_warn(dev, "Unable to read Pkg-TjMax from CPU:%u\n", cpu);
429 return 100000; /* Default TjMax: 100 degree celsius */
432 static int create_name_attr(struct platform_data *pdata, struct device *dev)
434 sysfs_attr_init(&pdata->name_attr.attr);
435 pdata->name_attr.attr.name = "name";
436 pdata->name_attr.attr.mode = S_IRUGO;
437 pdata->name_attr.show = show_name;
438 return device_create_file(dev, &pdata->name_attr);
441 static int create_core_attrs(struct temp_data *tdata, struct device *dev,
445 static ssize_t (*rd_ptr[TOTAL_ATTRS]) (struct device *dev,
446 struct device_attribute *devattr, char *buf) = {
447 show_label, show_crit_alarm, show_temp, show_tjmax,
448 show_max_alarm, show_ttarget, show_tmin };
449 static ssize_t (*rw_ptr[TOTAL_ATTRS]) (struct device *dev,
450 struct device_attribute *devattr, const char *buf,
451 size_t count) = { NULL, NULL, NULL, NULL, NULL,
452 store_ttarget, store_tmin };
453 static const char *names[TOTAL_ATTRS] = {
454 "temp%d_label", "temp%d_crit_alarm",
455 "temp%d_input", "temp%d_crit",
456 "temp%d_max_alarm", "temp%d_max",
459 for (i = 0; i < tdata->attr_size; i++) {
460 snprintf(tdata->attr_name[i], CORETEMP_NAME_LENGTH, names[i],
462 sysfs_attr_init(&tdata->sd_attrs[i].dev_attr.attr);
463 tdata->sd_attrs[i].dev_attr.attr.name = tdata->attr_name[i];
464 tdata->sd_attrs[i].dev_attr.attr.mode = S_IRUGO;
466 tdata->sd_attrs[i].dev_attr.attr.mode |= S_IWUSR;
467 tdata->sd_attrs[i].dev_attr.store = rw_ptr[i];
469 tdata->sd_attrs[i].dev_attr.show = rd_ptr[i];
470 tdata->sd_attrs[i].index = attr_no;
471 err = device_create_file(dev, &tdata->sd_attrs[i].dev_attr);
479 device_remove_file(dev, &tdata->sd_attrs[i].dev_attr);
484 static int __devinit chk_ucode_version(struct platform_device *pdev)
486 struct cpuinfo_x86 *c = &cpu_data(pdev->id);
491 * Check if we have problem with errata AE18 of Core processors:
492 * Readings might stop update when processor visited too deep sleep,
493 * fixed for stepping D0 (6EC).
495 if (c->x86_model == 0xe && c->x86_mask < 0xc) {
496 /* check for microcode update */
497 err = smp_call_function_single(pdev->id, get_ucode_rev_on_cpu,
501 "Cannot determine microcode revision of "
502 "CPU#%u (%d)!\n", pdev->id, err);
504 } else if (edx < 0x39) {
506 "Errata AE18 not fixed, update BIOS or "
507 "microcode of the CPU!\n");
514 static struct platform_device *coretemp_get_pdev(unsigned int cpu)
516 u16 phys_proc_id = TO_PHYS_ID(cpu);
517 struct pdev_entry *p;
519 mutex_lock(&pdev_list_mutex);
521 list_for_each_entry(p, &pdev_list, list)
522 if (p->phys_proc_id == phys_proc_id) {
523 mutex_unlock(&pdev_list_mutex);
527 mutex_unlock(&pdev_list_mutex);
531 static struct temp_data *init_temp_data(unsigned int cpu, int pkg_flag)
533 struct temp_data *tdata;
535 tdata = kzalloc(sizeof(struct temp_data), GFP_KERNEL);
539 tdata->status_reg = pkg_flag ? MSR_IA32_PACKAGE_THERM_STATUS :
540 MSR_IA32_THERM_STATUS;
541 tdata->intrpt_reg = pkg_flag ? MSR_IA32_PACKAGE_THERM_INTERRUPT :
542 MSR_IA32_THERM_INTERRUPT;
543 tdata->is_pkg_data = pkg_flag;
545 tdata->cpu_core_id = TO_CORE_ID(cpu);
546 tdata->attr_size = MAX_CORE_ATTRS;
547 mutex_init(&tdata->update_lock);
551 static int create_core_data(struct platform_data *pdata,
552 struct platform_device *pdev,
553 unsigned int cpu, int pkg_flag)
555 struct temp_data *tdata;
556 struct cpuinfo_x86 *c = &cpu_data(cpu);
561 * Find attr number for sysfs:
562 * We map the attr number to core id of the CPU
563 * The attr number is always core id + 2
564 * The Pkgtemp will always show up as temp1_*, if available
566 attr_no = pkg_flag ? 1 : TO_ATTR_NO(cpu);
568 if (attr_no > MAX_CORE_DATA - 1)
572 * Provide a single set of attributes for all HT siblings of a core
573 * to avoid duplicate sensors (the processor ID and core ID of all
574 * HT siblings of a core are the same).
575 * Skip if a HT sibling of this core is already registered.
576 * This is not an error.
578 if (pdata->core_data[attr_no] != NULL)
581 tdata = init_temp_data(cpu, pkg_flag);
585 /* Test if we can access the status register */
586 err = rdmsr_safe_on_cpu(cpu, tdata->status_reg, &eax, &edx);
590 /* We can access status register. Get Critical Temperature */
592 tdata->tjmax = get_pkg_tjmax(pdev->id, &pdev->dev);
594 tdata->tjmax = get_tjmax(c, cpu, &pdev->dev);
597 * Test if we can access the intrpt register. If so, increase the
598 * 'size' enough to have ttarget/tmin/max_alarm interfaces.
599 * Initialize ttarget with bits 16:22 of MSR_IA32_THERM_INTERRUPT
601 err = rdmsr_safe_on_cpu(cpu, tdata->intrpt_reg, &eax, &edx);
603 tdata->attr_size += MAX_THRESH_ATTRS;
604 tdata->tmin = tdata->tjmax -
605 ((eax & THERM_MASK_THRESHOLD0) >>
606 THERM_SHIFT_THRESHOLD0) * 1000;
607 tdata->ttarget = tdata->tjmax -
608 ((eax & THERM_MASK_THRESHOLD1) >>
609 THERM_SHIFT_THRESHOLD1) * 1000;
612 pdata->core_data[attr_no] = tdata;
614 /* Create sysfs interfaces */
615 err = create_core_attrs(tdata, &pdev->dev, attr_no);
625 static void coretemp_add_core(unsigned int cpu, int pkg_flag)
627 struct platform_data *pdata;
628 struct platform_device *pdev = coretemp_get_pdev(cpu);
634 pdata = platform_get_drvdata(pdev);
636 err = create_core_data(pdata, pdev, cpu, pkg_flag);
638 dev_err(&pdev->dev, "Adding Core %u failed\n", cpu);
641 static void coretemp_remove_core(struct platform_data *pdata,
642 struct device *dev, int indx)
645 struct temp_data *tdata = pdata->core_data[indx];
647 /* Remove the sysfs attributes */
648 for (i = 0; i < tdata->attr_size; i++)
649 device_remove_file(dev, &tdata->sd_attrs[i].dev_attr);
651 kfree(pdata->core_data[indx]);
652 pdata->core_data[indx] = NULL;
655 static int __devinit coretemp_probe(struct platform_device *pdev)
657 struct platform_data *pdata;
660 /* Check the microcode version of the CPU */
661 err = chk_ucode_version(pdev);
665 /* Initialize the per-package data structures */
666 pdata = kzalloc(sizeof(struct platform_data), GFP_KERNEL);
670 err = create_name_attr(pdata, &pdev->dev);
674 pdata->phys_proc_id = TO_PHYS_ID(pdev->id);
675 platform_set_drvdata(pdev, pdata);
677 pdata->hwmon_dev = hwmon_device_register(&pdev->dev);
678 if (IS_ERR(pdata->hwmon_dev)) {
679 err = PTR_ERR(pdata->hwmon_dev);
680 dev_err(&pdev->dev, "Class registration failed (%d)\n", err);
686 device_remove_file(&pdev->dev, &pdata->name_attr);
687 platform_set_drvdata(pdev, NULL);
693 static int __devexit coretemp_remove(struct platform_device *pdev)
695 struct platform_data *pdata = platform_get_drvdata(pdev);
698 for (i = MAX_CORE_DATA - 1; i >= 0; --i)
699 if (pdata->core_data[i])
700 coretemp_remove_core(pdata, &pdev->dev, i);
702 device_remove_file(&pdev->dev, &pdata->name_attr);
703 hwmon_device_unregister(pdata->hwmon_dev);
704 platform_set_drvdata(pdev, NULL);
709 static struct platform_driver coretemp_driver = {
711 .owner = THIS_MODULE,
714 .probe = coretemp_probe,
715 .remove = __devexit_p(coretemp_remove),
718 static int __cpuinit coretemp_device_add(unsigned int cpu)
721 struct platform_device *pdev;
722 struct pdev_entry *pdev_entry;
724 mutex_lock(&pdev_list_mutex);
726 pdev = platform_device_alloc(DRVNAME, cpu);
729 pr_err("Device allocation failed\n");
733 pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL);
736 goto exit_device_put;
739 err = platform_device_add(pdev);
741 pr_err("Device addition failed (%d)\n", err);
742 goto exit_device_free;
745 pdev_entry->pdev = pdev;
746 pdev_entry->phys_proc_id = TO_PHYS_ID(cpu);
748 list_add_tail(&pdev_entry->list, &pdev_list);
749 mutex_unlock(&pdev_list_mutex);
756 platform_device_put(pdev);
758 mutex_unlock(&pdev_list_mutex);
762 static void coretemp_device_remove(unsigned int cpu)
764 struct pdev_entry *p, *n;
765 u16 phys_proc_id = TO_PHYS_ID(cpu);
767 mutex_lock(&pdev_list_mutex);
768 list_for_each_entry_safe(p, n, &pdev_list, list) {
769 if (p->phys_proc_id != phys_proc_id)
771 platform_device_unregister(p->pdev);
775 mutex_unlock(&pdev_list_mutex);
778 static bool is_any_core_online(struct platform_data *pdata)
782 /* Find online cores, except pkgtemp data */
783 for (i = MAX_CORE_DATA - 1; i >= 0; --i) {
784 if (pdata->core_data[i] &&
785 !pdata->core_data[i]->is_pkg_data) {
792 static void __cpuinit get_core_online(unsigned int cpu)
794 struct cpuinfo_x86 *c = &cpu_data(cpu);
795 struct platform_device *pdev = coretemp_get_pdev(cpu);
799 * CPUID.06H.EAX[0] indicates whether the CPU has thermal
800 * sensors. We check this bit only, all the early CPUs
801 * without thermal sensors will be filtered out.
803 if (!cpu_has(c, X86_FEATURE_DTS))
808 * Alright, we have DTS support.
809 * We are bringing the _first_ core in this pkg
810 * online. So, initialize per-pkg data structures and
811 * then bring this core online.
813 err = coretemp_device_add(cpu);
817 * Check whether pkgtemp support is available.
818 * If so, add interfaces for pkgtemp.
820 if (cpu_has(c, X86_FEATURE_PTS))
821 coretemp_add_core(cpu, 1);
824 * Physical CPU device already exists.
825 * So, just add interfaces for this core.
827 coretemp_add_core(cpu, 0);
830 static void __cpuinit put_core_offline(unsigned int cpu)
833 struct platform_data *pdata;
834 struct platform_device *pdev = coretemp_get_pdev(cpu);
836 /* If the physical CPU device does not exist, just return */
840 pdata = platform_get_drvdata(pdev);
842 indx = TO_ATTR_NO(cpu);
844 if (pdata->core_data[indx] && pdata->core_data[indx]->cpu == cpu)
845 coretemp_remove_core(pdata, &pdev->dev, indx);
848 * If a HT sibling of a core is taken offline, but another HT sibling
849 * of the same core is still online, register the alternate sibling.
850 * This ensures that exactly one set of attributes is provided as long
851 * as at least one HT sibling of a core is online.
853 for_each_sibling(i, cpu) {
857 * Display temperature sensor data for one HT sibling
858 * per core only, so abort the loop after one such
859 * sibling has been found.
865 * If all cores in this pkg are offline, remove the device.
866 * coretemp_device_remove calls unregister_platform_device,
867 * which in turn calls coretemp_remove. This removes the
868 * pkgtemp entry and does other clean ups.
870 if (!is_any_core_online(pdata))
871 coretemp_device_remove(cpu);
874 static int __cpuinit coretemp_cpu_callback(struct notifier_block *nfb,
875 unsigned long action, void *hcpu)
877 unsigned int cpu = (unsigned long) hcpu;
881 case CPU_DOWN_FAILED:
882 get_core_online(cpu);
884 case CPU_DOWN_PREPARE:
885 put_core_offline(cpu);
891 static struct notifier_block coretemp_cpu_notifier __refdata = {
892 .notifier_call = coretemp_cpu_callback,
895 static int __init coretemp_init(void)
897 int i, err = -ENODEV;
899 /* quick check if we run Intel */
900 if (cpu_data(0).x86_vendor != X86_VENDOR_INTEL)
903 err = platform_driver_register(&coretemp_driver);
907 for_each_online_cpu(i)
910 #ifndef CONFIG_HOTPLUG_CPU
911 if (list_empty(&pdev_list)) {
913 goto exit_driver_unreg;
917 register_hotcpu_notifier(&coretemp_cpu_notifier);
920 #ifndef CONFIG_HOTPLUG_CPU
922 platform_driver_unregister(&coretemp_driver);
928 static void __exit coretemp_exit(void)
930 struct pdev_entry *p, *n;
932 unregister_hotcpu_notifier(&coretemp_cpu_notifier);
933 mutex_lock(&pdev_list_mutex);
934 list_for_each_entry_safe(p, n, &pdev_list, list) {
935 platform_device_unregister(p->pdev);
939 mutex_unlock(&pdev_list_mutex);
940 platform_driver_unregister(&coretemp_driver);
943 MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
944 MODULE_DESCRIPTION("Intel Core temperature monitor");
945 MODULE_LICENSE("GPL");
947 module_init(coretemp_init)
948 module_exit(coretemp_exit)