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v3.1
  1/*
  2 * coretemp.c - Linux kernel module for hardware monitoring
  3 *
  4 * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
  5 *
  6 * Inspired from many hwmon drivers
  7 *
  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.
 11 *
 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.
 16 *
 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
 20 * 02110-1301 USA.
 21 */
 22
 23#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 24
 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>
 39#include <linux/moduleparam.h>
 
 40#include <asm/msr.h>
 41#include <asm/processor.h>
 
 42
 43#define DRVNAME	"coretemp"
 44
 45/*
 46 * force_tjmax only matters when TjMax can't be read from the CPU itself.
 47 * When set, it replaces the driver's suboptimal heuristic.
 48 */
 49static int force_tjmax;
 50module_param_named(tjmax, force_tjmax, int, 0444);
 51MODULE_PARM_DESC(tjmax, "TjMax value in degrees Celsius");
 52
 53#define BASE_SYSFS_ATTR_NO	2	/* Sysfs Base attr no for coretemp */
 54#define NUM_REAL_CORES		16	/* Number of Real cores per cpu */
 55#define CORETEMP_NAME_LENGTH	17	/* String Length of attrs */
 56#define MAX_CORE_ATTRS		4	/* Maximum no of basic attrs */
 57#define TOTAL_ATTRS		(MAX_CORE_ATTRS + 1)
 58#define MAX_CORE_DATA		(NUM_REAL_CORES + BASE_SYSFS_ATTR_NO)
 59
 60#ifdef CONFIG_SMP
 61#define TO_PHYS_ID(cpu)		cpu_data(cpu).phys_proc_id
 62#define TO_CORE_ID(cpu)		cpu_data(cpu).cpu_core_id
 63#define TO_ATTR_NO(cpu)		(TO_CORE_ID(cpu) + BASE_SYSFS_ATTR_NO)
 
 
 64#define for_each_sibling(i, cpu)	for_each_cpu(i, cpu_sibling_mask(cpu))
 65#else
 66#define TO_PHYS_ID(cpu)		(cpu)
 67#define TO_CORE_ID(cpu)		(cpu)
 68#define TO_ATTR_NO(cpu)		(cpu)
 69#define for_each_sibling(i, cpu)	for (i = 0; false; )
 70#endif
 71
 72/*
 73 * Per-Core Temperature Data
 74 * @last_updated: The time when the current temperature value was updated
 75 *		earlier (in jiffies).
 76 * @cpu_core_id: The CPU Core from which temperature values should be read
 77 *		This value is passed as "id" field to rdmsr/wrmsr functions.
 78 * @status_reg: One of IA32_THERM_STATUS or IA32_PACKAGE_THERM_STATUS,
 79 *		from where the temperature values should be read.
 80 * @attr_size:  Total number of pre-core attrs displayed in the sysfs.
 81 * @is_pkg_data: If this is 1, the temp_data holds pkgtemp data.
 82 *		Otherwise, temp_data holds coretemp data.
 83 * @valid: If this is 1, the current temperature is valid.
 84 */
 85struct temp_data {
 86	int temp;
 87	int ttarget;
 88	int tjmax;
 89	unsigned long last_updated;
 90	unsigned int cpu;
 91	u32 cpu_core_id;
 92	u32 status_reg;
 93	int attr_size;
 94	bool is_pkg_data;
 95	bool valid;
 96	struct sensor_device_attribute sd_attrs[TOTAL_ATTRS];
 97	char attr_name[TOTAL_ATTRS][CORETEMP_NAME_LENGTH];
 
 
 98	struct mutex update_lock;
 99};
100
101/* Platform Data per Physical CPU */
102struct platform_data {
103	struct device *hwmon_dev;
104	u16 phys_proc_id;
105	struct temp_data *core_data[MAX_CORE_DATA];
106	struct device_attribute name_attr;
107};
108
109struct pdev_entry {
110	struct list_head list;
111	struct platform_device *pdev;
112	u16 phys_proc_id;
113};
114
115static LIST_HEAD(pdev_list);
116static DEFINE_MUTEX(pdev_list_mutex);
117
118static ssize_t show_name(struct device *dev,
119			struct device_attribute *devattr, char *buf)
120{
121	return sprintf(buf, "%s\n", DRVNAME);
122}
123
124static ssize_t show_label(struct device *dev,
125				struct device_attribute *devattr, char *buf)
126{
127	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
128	struct platform_data *pdata = dev_get_drvdata(dev);
129	struct temp_data *tdata = pdata->core_data[attr->index];
130
131	if (tdata->is_pkg_data)
132		return sprintf(buf, "Physical id %u\n", pdata->phys_proc_id);
133
134	return sprintf(buf, "Core %u\n", tdata->cpu_core_id);
135}
136
137static ssize_t show_crit_alarm(struct device *dev,
138				struct device_attribute *devattr, char *buf)
139{
140	u32 eax, edx;
141	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
142	struct platform_data *pdata = dev_get_drvdata(dev);
143	struct temp_data *tdata = pdata->core_data[attr->index];
144
145	rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
146
147	return sprintf(buf, "%d\n", (eax >> 5) & 1);
148}
149
150static ssize_t show_tjmax(struct device *dev,
151			struct device_attribute *devattr, char *buf)
152{
153	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
154	struct platform_data *pdata = dev_get_drvdata(dev);
155
156	return sprintf(buf, "%d\n", pdata->core_data[attr->index]->tjmax);
157}
158
159static ssize_t show_ttarget(struct device *dev,
160				struct device_attribute *devattr, char *buf)
161{
162	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
163	struct platform_data *pdata = dev_get_drvdata(dev);
164
165	return sprintf(buf, "%d\n", pdata->core_data[attr->index]->ttarget);
166}
167
168static ssize_t show_temp(struct device *dev,
169			struct device_attribute *devattr, char *buf)
170{
171	u32 eax, edx;
172	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
173	struct platform_data *pdata = dev_get_drvdata(dev);
174	struct temp_data *tdata = pdata->core_data[attr->index];
175
176	mutex_lock(&tdata->update_lock);
177
178	/* Check whether the time interval has elapsed */
179	if (!tdata->valid || time_after(jiffies, tdata->last_updated + HZ)) {
180		rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
181		tdata->valid = 0;
182		/* Check whether the data is valid */
183		if (eax & 0x80000000) {
184			tdata->temp = tdata->tjmax -
185					((eax >> 16) & 0x7f) * 1000;
186			tdata->valid = 1;
187		}
 
188		tdata->last_updated = jiffies;
189	}
190
191	mutex_unlock(&tdata->update_lock);
192	return tdata->valid ? sprintf(buf, "%d\n", tdata->temp) : -EAGAIN;
193}
194
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
195static int adjust_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev)
196{
197	/* The 100C is default for both mobile and non mobile CPUs */
198
199	int tjmax = 100000;
200	int tjmax_ee = 85000;
201	int usemsr_ee = 1;
202	int err;
203	u32 eax, edx;
204	struct pci_dev *host_bridge;
205
206	/* Early chips have no MSR for TjMax */
207
208	if (c->x86_model == 0xf && c->x86_mask < 4)
209		usemsr_ee = 0;
210
211	/* Atom CPUs */
 
 
 
 
 
 
 
 
 
 
212
213	if (c->x86_model == 0x1c) {
214		usemsr_ee = 0;
 
 
215
216		host_bridge = pci_get_bus_and_slot(0, PCI_DEVFN(0, 0));
 
 
 
 
 
217
218		if (host_bridge && host_bridge->vendor == PCI_VENDOR_ID_INTEL
219		    && (host_bridge->device == 0xa000	/* NM10 based nettop */
220		    || host_bridge->device == 0xa010))	/* NM10 based netbook */
221			tjmax = 100000;
222		else
223			tjmax = 90000;
224
225		pci_dev_put(host_bridge);
226	}
227
228	if (c->x86_model > 0xe && usemsr_ee) {
229		u8 platform_id;
230
231		/*
232		 * Now we can detect the mobile CPU using Intel provided table
233		 * http://softwarecommunity.intel.com/Wiki/Mobility/720.htm
234		 * For Core2 cores, check MSR 0x17, bit 28 1 = Mobile CPU
235		 */
236		err = rdmsr_safe_on_cpu(id, 0x17, &eax, &edx);
237		if (err) {
238			dev_warn(dev,
239				 "Unable to access MSR 0x17, assuming desktop"
240				 " CPU\n");
241			usemsr_ee = 0;
242		} else if (c->x86_model < 0x17 && !(eax & 0x10000000)) {
243			/*
244			 * Trust bit 28 up to Penryn, I could not find any
245			 * documentation on that; if you happen to know
246			 * someone at Intel please ask
247			 */
248			usemsr_ee = 0;
249		} else {
250			/* Platform ID bits 52:50 (EDX starts at bit 32) */
251			platform_id = (edx >> 18) & 0x7;
252
253			/*
254			 * Mobile Penryn CPU seems to be platform ID 7 or 5
255			 * (guesswork)
256			 */
257			if (c->x86_model == 0x17 &&
258			    (platform_id == 5 || platform_id == 7)) {
259				/*
260				 * If MSR EE bit is set, set it to 90 degrees C,
261				 * otherwise 105 degrees C
262				 */
263				tjmax_ee = 90000;
264				tjmax = 105000;
265			}
266		}
267	}
268
269	if (usemsr_ee) {
270		err = rdmsr_safe_on_cpu(id, 0xee, &eax, &edx);
271		if (err) {
272			dev_warn(dev,
273				 "Unable to access MSR 0xEE, for Tjmax, left"
274				 " at default\n");
275		} else if (eax & 0x40000000) {
276			tjmax = tjmax_ee;
277		}
278	} else if (tjmax == 100000) {
279		/*
280		 * If we don't use msr EE it means we are desktop CPU
281		 * (with exeception of Atom)
282		 */
283		dev_warn(dev, "Using relative temperature scale!\n");
284	}
285
286	return tjmax;
287}
288
 
 
 
 
 
 
 
 
 
 
 
 
289static int get_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev)
290{
291	int err;
292	u32 eax, edx;
293	u32 val;
294
295	/*
296	 * A new feature of current Intel(R) processors, the
297	 * IA32_TEMPERATURE_TARGET contains the TjMax value
298	 */
299	err = rdmsr_safe_on_cpu(id, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
300	if (err) {
301		if (c->x86_model > 0xe && c->x86_model != 0x1c)
302			dev_warn(dev, "Unable to read TjMax from CPU %u\n", id);
303	} else {
304		val = (eax >> 16) & 0xff;
305		/*
306		 * If the TjMax is not plausible, an assumption
307		 * will be used
308		 */
309		if (val) {
310			dev_dbg(dev, "TjMax is %d degrees C\n", val);
311			return val * 1000;
312		}
313	}
314
315	if (force_tjmax) {
316		dev_notice(dev, "TjMax forced to %d degrees C by user\n",
317			   force_tjmax);
318		return force_tjmax * 1000;
319	}
320
321	/*
322	 * An assumption is made for early CPUs and unreadable MSR.
323	 * NOTE: the calculated value may not be correct.
324	 */
325	return adjust_tjmax(c, id, dev);
326}
327
328static void __devinit get_ucode_rev_on_cpu(void *edx)
329{
330	u32 eax;
331
332	wrmsr(MSR_IA32_UCODE_REV, 0, 0);
333	sync_core();
334	rdmsr(MSR_IA32_UCODE_REV, eax, *(u32 *)edx);
335}
336
337static int create_name_attr(struct platform_data *pdata, struct device *dev)
338{
339	sysfs_attr_init(&pdata->name_attr.attr);
340	pdata->name_attr.attr.name = "name";
341	pdata->name_attr.attr.mode = S_IRUGO;
342	pdata->name_attr.show = show_name;
343	return device_create_file(dev, &pdata->name_attr);
344}
345
346static int create_core_attrs(struct temp_data *tdata, struct device *dev,
347				int attr_no)
348{
349	int err, i;
350	static ssize_t (*const rd_ptr[TOTAL_ATTRS]) (struct device *dev,
351			struct device_attribute *devattr, char *buf) = {
352			show_label, show_crit_alarm, show_temp, show_tjmax,
353			show_ttarget };
354	static const char *const names[TOTAL_ATTRS] = {
355					"temp%d_label", "temp%d_crit_alarm",
356					"temp%d_input", "temp%d_crit",
357					"temp%d_max" };
358
359	for (i = 0; i < tdata->attr_size; i++) {
360		snprintf(tdata->attr_name[i], CORETEMP_NAME_LENGTH, names[i],
361			attr_no);
362		sysfs_attr_init(&tdata->sd_attrs[i].dev_attr.attr);
363		tdata->sd_attrs[i].dev_attr.attr.name = tdata->attr_name[i];
364		tdata->sd_attrs[i].dev_attr.attr.mode = S_IRUGO;
365		tdata->sd_attrs[i].dev_attr.show = rd_ptr[i];
366		tdata->sd_attrs[i].index = attr_no;
367		err = device_create_file(dev, &tdata->sd_attrs[i].dev_attr);
368		if (err)
369			goto exit_free;
370	}
371	return 0;
372
373exit_free:
374	while (--i >= 0)
375		device_remove_file(dev, &tdata->sd_attrs[i].dev_attr);
376	return err;
377}
378
379
380static int __cpuinit chk_ucode_version(unsigned int cpu)
381{
382	struct cpuinfo_x86 *c = &cpu_data(cpu);
383	int err;
384	u32 edx;
385
386	/*
387	 * Check if we have problem with errata AE18 of Core processors:
388	 * Readings might stop update when processor visited too deep sleep,
389	 * fixed for stepping D0 (6EC).
390	 */
391	if (c->x86_model == 0xe && c->x86_mask < 0xc) {
392		/* check for microcode update */
393		err = smp_call_function_single(cpu, get_ucode_rev_on_cpu,
394					       &edx, 1);
395		if (err) {
396			pr_err("Cannot determine microcode revision of "
397			       "CPU#%u (%d)!\n", cpu, err);
398			return -ENODEV;
399		} else if (edx < 0x39) {
400			pr_err("Errata AE18 not fixed, update BIOS or "
401			       "microcode of the CPU!\n");
402			return -ENODEV;
403		}
404	}
405	return 0;
406}
407
408static struct platform_device *coretemp_get_pdev(unsigned int cpu)
409{
410	u16 phys_proc_id = TO_PHYS_ID(cpu);
411	struct pdev_entry *p;
412
413	mutex_lock(&pdev_list_mutex);
414
415	list_for_each_entry(p, &pdev_list, list)
416		if (p->phys_proc_id == phys_proc_id) {
417			mutex_unlock(&pdev_list_mutex);
418			return p->pdev;
419		}
420
421	mutex_unlock(&pdev_list_mutex);
422	return NULL;
423}
424
425static struct temp_data *init_temp_data(unsigned int cpu, int pkg_flag)
426{
427	struct temp_data *tdata;
428
429	tdata = kzalloc(sizeof(struct temp_data), GFP_KERNEL);
430	if (!tdata)
431		return NULL;
432
433	tdata->status_reg = pkg_flag ? MSR_IA32_PACKAGE_THERM_STATUS :
434							MSR_IA32_THERM_STATUS;
435	tdata->is_pkg_data = pkg_flag;
436	tdata->cpu = cpu;
437	tdata->cpu_core_id = TO_CORE_ID(cpu);
438	tdata->attr_size = MAX_CORE_ATTRS;
439	mutex_init(&tdata->update_lock);
440	return tdata;
441}
442
443static int create_core_data(struct platform_device *pdev,
444				unsigned int cpu, int pkg_flag)
445{
446	struct temp_data *tdata;
447	struct platform_data *pdata = platform_get_drvdata(pdev);
448	struct cpuinfo_x86 *c = &cpu_data(cpu);
449	u32 eax, edx;
450	int err, attr_no;
451
452	/*
453	 * Find attr number for sysfs:
454	 * We map the attr number to core id of the CPU
455	 * The attr number is always core id + 2
456	 * The Pkgtemp will always show up as temp1_*, if available
457	 */
458	attr_no = pkg_flag ? 1 : TO_ATTR_NO(cpu);
459
460	if (attr_no > MAX_CORE_DATA - 1)
461		return -ERANGE;
462
463	/*
464	 * Provide a single set of attributes for all HT siblings of a core
465	 * to avoid duplicate sensors (the processor ID and core ID of all
466	 * HT siblings of a core are the same).
467	 * Skip if a HT sibling of this core is already registered.
468	 * This is not an error.
469	 */
470	if (pdata->core_data[attr_no] != NULL)
471		return 0;
472
473	tdata = init_temp_data(cpu, pkg_flag);
474	if (!tdata)
475		return -ENOMEM;
476
477	/* Test if we can access the status register */
478	err = rdmsr_safe_on_cpu(cpu, tdata->status_reg, &eax, &edx);
479	if (err)
480		goto exit_free;
481
482	/* We can access status register. Get Critical Temperature */
483	tdata->tjmax = get_tjmax(c, cpu, &pdev->dev);
484
485	/*
486	 * Read the still undocumented bits 8:15 of IA32_TEMPERATURE_TARGET.
487	 * The target temperature is available on older CPUs but not in this
488	 * register. Atoms don't have the register at all.
489	 */
490	if (c->x86_model > 0xe && c->x86_model != 0x1c) {
491		err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET,
492					&eax, &edx);
493		if (!err) {
494			tdata->ttarget
495			  = tdata->tjmax - ((eax >> 8) & 0xff) * 1000;
496			tdata->attr_size++;
497		}
498	}
499
500	pdata->core_data[attr_no] = tdata;
501
502	/* Create sysfs interfaces */
503	err = create_core_attrs(tdata, &pdev->dev, attr_no);
504	if (err)
505		goto exit_free;
506
507	return 0;
508exit_free:
509	pdata->core_data[attr_no] = NULL;
510	kfree(tdata);
511	return err;
512}
513
514static void coretemp_add_core(unsigned int cpu, int pkg_flag)
515{
516	struct platform_device *pdev = coretemp_get_pdev(cpu);
517	int err;
518
519	if (!pdev)
520		return;
521
522	err = create_core_data(pdev, cpu, pkg_flag);
523	if (err)
524		dev_err(&pdev->dev, "Adding Core %u failed\n", cpu);
525}
526
527static void coretemp_remove_core(struct platform_data *pdata,
528				struct device *dev, int indx)
529{
530	int i;
531	struct temp_data *tdata = pdata->core_data[indx];
532
533	/* Remove the sysfs attributes */
534	for (i = 0; i < tdata->attr_size; i++)
535		device_remove_file(dev, &tdata->sd_attrs[i].dev_attr);
536
537	kfree(pdata->core_data[indx]);
538	pdata->core_data[indx] = NULL;
539}
540
541static int __devinit coretemp_probe(struct platform_device *pdev)
542{
 
543	struct platform_data *pdata;
544	int err;
545
546	/* Initialize the per-package data structures */
547	pdata = kzalloc(sizeof(struct platform_data), GFP_KERNEL);
548	if (!pdata)
549		return -ENOMEM;
550
551	err = create_name_attr(pdata, &pdev->dev);
552	if (err)
553		goto exit_free;
554
555	pdata->phys_proc_id = pdev->id;
556	platform_set_drvdata(pdev, pdata);
557
558	pdata->hwmon_dev = hwmon_device_register(&pdev->dev);
559	if (IS_ERR(pdata->hwmon_dev)) {
560		err = PTR_ERR(pdata->hwmon_dev);
561		dev_err(&pdev->dev, "Class registration failed (%d)\n", err);
562		goto exit_name;
563	}
564	return 0;
565
566exit_name:
567	device_remove_file(&pdev->dev, &pdata->name_attr);
568	platform_set_drvdata(pdev, NULL);
569exit_free:
570	kfree(pdata);
571	return err;
572}
573
574static int __devexit coretemp_remove(struct platform_device *pdev)
575{
576	struct platform_data *pdata = platform_get_drvdata(pdev);
577	int i;
578
579	for (i = MAX_CORE_DATA - 1; i >= 0; --i)
580		if (pdata->core_data[i])
581			coretemp_remove_core(pdata, &pdev->dev, i);
582
583	device_remove_file(&pdev->dev, &pdata->name_attr);
584	hwmon_device_unregister(pdata->hwmon_dev);
585	platform_set_drvdata(pdev, NULL);
586	kfree(pdata);
587	return 0;
588}
589
590static struct platform_driver coretemp_driver = {
591	.driver = {
592		.owner = THIS_MODULE,
593		.name = DRVNAME,
594	},
595	.probe = coretemp_probe,
596	.remove = __devexit_p(coretemp_remove),
597};
598
599static int __cpuinit coretemp_device_add(unsigned int cpu)
600{
601	int err;
602	struct platform_device *pdev;
603	struct pdev_entry *pdev_entry;
604
605	mutex_lock(&pdev_list_mutex);
606
607	pdev = platform_device_alloc(DRVNAME, TO_PHYS_ID(cpu));
608	if (!pdev) {
609		err = -ENOMEM;
610		pr_err("Device allocation failed\n");
611		goto exit;
612	}
613
614	pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL);
615	if (!pdev_entry) {
616		err = -ENOMEM;
617		goto exit_device_put;
618	}
619
620	err = platform_device_add(pdev);
621	if (err) {
622		pr_err("Device addition failed (%d)\n", err);
623		goto exit_device_free;
624	}
625
626	pdev_entry->pdev = pdev;
627	pdev_entry->phys_proc_id = pdev->id;
628
629	list_add_tail(&pdev_entry->list, &pdev_list);
630	mutex_unlock(&pdev_list_mutex);
631
632	return 0;
633
634exit_device_free:
635	kfree(pdev_entry);
636exit_device_put:
637	platform_device_put(pdev);
638exit:
639	mutex_unlock(&pdev_list_mutex);
640	return err;
641}
642
643static void coretemp_device_remove(unsigned int cpu)
644{
645	struct pdev_entry *p, *n;
646	u16 phys_proc_id = TO_PHYS_ID(cpu);
647
648	mutex_lock(&pdev_list_mutex);
649	list_for_each_entry_safe(p, n, &pdev_list, list) {
650		if (p->phys_proc_id != phys_proc_id)
651			continue;
652		platform_device_unregister(p->pdev);
653		list_del(&p->list);
654		kfree(p);
655	}
656	mutex_unlock(&pdev_list_mutex);
657}
658
659static bool is_any_core_online(struct platform_data *pdata)
660{
661	int i;
662
663	/* Find online cores, except pkgtemp data */
664	for (i = MAX_CORE_DATA - 1; i >= 0; --i) {
665		if (pdata->core_data[i] &&
666			!pdata->core_data[i]->is_pkg_data) {
667			return true;
668		}
669	}
670	return false;
671}
672
673static void __cpuinit get_core_online(unsigned int cpu)
674{
675	struct cpuinfo_x86 *c = &cpu_data(cpu);
676	struct platform_device *pdev = coretemp_get_pdev(cpu);
677	int err;
678
679	/*
680	 * CPUID.06H.EAX[0] indicates whether the CPU has thermal
681	 * sensors. We check this bit only, all the early CPUs
682	 * without thermal sensors will be filtered out.
683	 */
684	if (!cpu_has(c, X86_FEATURE_DTS))
685		return;
686
687	if (!pdev) {
688		/* Check the microcode version of the CPU */
689		if (chk_ucode_version(cpu))
690			return;
691
692		/*
693		 * Alright, we have DTS support.
694		 * We are bringing the _first_ core in this pkg
695		 * online. So, initialize per-pkg data structures and
696		 * then bring this core online.
697		 */
698		err = coretemp_device_add(cpu);
699		if (err)
700			return;
701		/*
702		 * Check whether pkgtemp support is available.
703		 * If so, add interfaces for pkgtemp.
704		 */
705		if (cpu_has(c, X86_FEATURE_PTS))
706			coretemp_add_core(cpu, 1);
707	}
708	/*
709	 * Physical CPU device already exists.
710	 * So, just add interfaces for this core.
711	 */
712	coretemp_add_core(cpu, 0);
713}
714
715static void __cpuinit put_core_offline(unsigned int cpu)
716{
717	int i, indx;
718	struct platform_data *pdata;
719	struct platform_device *pdev = coretemp_get_pdev(cpu);
720
721	/* If the physical CPU device does not exist, just return */
722	if (!pdev)
723		return;
724
725	pdata = platform_get_drvdata(pdev);
726
727	indx = TO_ATTR_NO(cpu);
728
 
 
 
 
729	if (pdata->core_data[indx] && pdata->core_data[indx]->cpu == cpu)
730		coretemp_remove_core(pdata, &pdev->dev, indx);
731
732	/*
733	 * If a HT sibling of a core is taken offline, but another HT sibling
734	 * of the same core is still online, register the alternate sibling.
735	 * This ensures that exactly one set of attributes is provided as long
736	 * as at least one HT sibling of a core is online.
737	 */
738	for_each_sibling(i, cpu) {
739		if (i != cpu) {
740			get_core_online(i);
741			/*
742			 * Display temperature sensor data for one HT sibling
743			 * per core only, so abort the loop after one such
744			 * sibling has been found.
745			 */
746			break;
747		}
748	}
749	/*
750	 * If all cores in this pkg are offline, remove the device.
751	 * coretemp_device_remove calls unregister_platform_device,
752	 * which in turn calls coretemp_remove. This removes the
753	 * pkgtemp entry and does other clean ups.
754	 */
755	if (!is_any_core_online(pdata))
756		coretemp_device_remove(cpu);
757}
758
759static int __cpuinit coretemp_cpu_callback(struct notifier_block *nfb,
760				 unsigned long action, void *hcpu)
761{
762	unsigned int cpu = (unsigned long) hcpu;
763
764	switch (action) {
765	case CPU_ONLINE:
766	case CPU_DOWN_FAILED:
767		get_core_online(cpu);
768		break;
769	case CPU_DOWN_PREPARE:
770		put_core_offline(cpu);
771		break;
772	}
773	return NOTIFY_OK;
774}
775
776static struct notifier_block coretemp_cpu_notifier __refdata = {
777	.notifier_call = coretemp_cpu_callback,
778};
779
 
 
 
 
 
 
780static int __init coretemp_init(void)
781{
782	int i, err = -ENODEV;
783
784	/* quick check if we run Intel */
785	if (cpu_data(0).x86_vendor != X86_VENDOR_INTEL)
786		goto exit;
 
 
 
 
787
788	err = platform_driver_register(&coretemp_driver);
789	if (err)
790		goto exit;
791
 
792	for_each_online_cpu(i)
793		get_core_online(i);
794
795#ifndef CONFIG_HOTPLUG_CPU
796	if (list_empty(&pdev_list)) {
 
797		err = -ENODEV;
798		goto exit_driver_unreg;
799	}
800#endif
801
802	register_hotcpu_notifier(&coretemp_cpu_notifier);
 
803	return 0;
804
805#ifndef CONFIG_HOTPLUG_CPU
806exit_driver_unreg:
807	platform_driver_unregister(&coretemp_driver);
808#endif
809exit:
810	return err;
811}
812
813static void __exit coretemp_exit(void)
814{
815	struct pdev_entry *p, *n;
816
817	unregister_hotcpu_notifier(&coretemp_cpu_notifier);
 
818	mutex_lock(&pdev_list_mutex);
819	list_for_each_entry_safe(p, n, &pdev_list, list) {
820		platform_device_unregister(p->pdev);
821		list_del(&p->list);
822		kfree(p);
823	}
824	mutex_unlock(&pdev_list_mutex);
 
825	platform_driver_unregister(&coretemp_driver);
826}
827
828MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
829MODULE_DESCRIPTION("Intel Core temperature monitor");
830MODULE_LICENSE("GPL");
831
832module_init(coretemp_init)
833module_exit(coretemp_exit)
v3.15
  1/*
  2 * coretemp.c - Linux kernel module for hardware monitoring
  3 *
  4 * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
  5 *
  6 * Inspired from many hwmon drivers
  7 *
  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.
 11 *
 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.
 16 *
 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
 20 * 02110-1301 USA.
 21 */
 22
 23#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 24
 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/smp.h>
 38#include <linux/moduleparam.h>
 39#include <linux/pci.h>
 40#include <asm/msr.h>
 41#include <asm/processor.h>
 42#include <asm/cpu_device_id.h>
 43
 44#define DRVNAME	"coretemp"
 45
 46/*
 47 * force_tjmax only matters when TjMax can't be read from the CPU itself.
 48 * When set, it replaces the driver's suboptimal heuristic.
 49 */
 50static int force_tjmax;
 51module_param_named(tjmax, force_tjmax, int, 0444);
 52MODULE_PARM_DESC(tjmax, "TjMax value in degrees Celsius");
 53
 54#define BASE_SYSFS_ATTR_NO	2	/* Sysfs Base attr no for coretemp */
 55#define NUM_REAL_CORES		32	/* Number of Real cores per cpu */
 56#define CORETEMP_NAME_LENGTH	19	/* String Length of attrs */
 57#define MAX_CORE_ATTRS		4	/* Maximum no of basic attrs */
 58#define TOTAL_ATTRS		(MAX_CORE_ATTRS + 1)
 59#define MAX_CORE_DATA		(NUM_REAL_CORES + BASE_SYSFS_ATTR_NO)
 60
 61#define TO_PHYS_ID(cpu)		(cpu_data(cpu).phys_proc_id)
 62#define TO_CORE_ID(cpu)		(cpu_data(cpu).cpu_core_id)
 
 63#define TO_ATTR_NO(cpu)		(TO_CORE_ID(cpu) + BASE_SYSFS_ATTR_NO)
 64
 65#ifdef CONFIG_SMP
 66#define for_each_sibling(i, cpu)	for_each_cpu(i, cpu_sibling_mask(cpu))
 67#else
 
 
 
 68#define for_each_sibling(i, cpu)	for (i = 0; false; )
 69#endif
 70
 71/*
 72 * Per-Core Temperature Data
 73 * @last_updated: The time when the current temperature value was updated
 74 *		earlier (in jiffies).
 75 * @cpu_core_id: The CPU Core from which temperature values should be read
 76 *		This value is passed as "id" field to rdmsr/wrmsr functions.
 77 * @status_reg: One of IA32_THERM_STATUS or IA32_PACKAGE_THERM_STATUS,
 78 *		from where the temperature values should be read.
 79 * @attr_size:  Total number of pre-core attrs displayed in the sysfs.
 80 * @is_pkg_data: If this is 1, the temp_data holds pkgtemp data.
 81 *		Otherwise, temp_data holds coretemp data.
 82 * @valid: If this is 1, the current temperature is valid.
 83 */
 84struct temp_data {
 85	int temp;
 86	int ttarget;
 87	int tjmax;
 88	unsigned long last_updated;
 89	unsigned int cpu;
 90	u32 cpu_core_id;
 91	u32 status_reg;
 92	int attr_size;
 93	bool is_pkg_data;
 94	bool valid;
 95	struct sensor_device_attribute sd_attrs[TOTAL_ATTRS];
 96	char attr_name[TOTAL_ATTRS][CORETEMP_NAME_LENGTH];
 97	struct attribute *attrs[TOTAL_ATTRS + 1];
 98	struct attribute_group attr_group;
 99	struct mutex update_lock;
100};
101
102/* Platform Data per Physical CPU */
103struct platform_data {
104	struct device *hwmon_dev;
105	u16 phys_proc_id;
106	struct temp_data *core_data[MAX_CORE_DATA];
107	struct device_attribute name_attr;
108};
109
110struct pdev_entry {
111	struct list_head list;
112	struct platform_device *pdev;
113	u16 phys_proc_id;
114};
115
116static LIST_HEAD(pdev_list);
117static DEFINE_MUTEX(pdev_list_mutex);
118
 
 
 
 
 
 
119static ssize_t show_label(struct device *dev,
120				struct device_attribute *devattr, char *buf)
121{
122	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
123	struct platform_data *pdata = dev_get_drvdata(dev);
124	struct temp_data *tdata = pdata->core_data[attr->index];
125
126	if (tdata->is_pkg_data)
127		return sprintf(buf, "Physical id %u\n", pdata->phys_proc_id);
128
129	return sprintf(buf, "Core %u\n", tdata->cpu_core_id);
130}
131
132static ssize_t show_crit_alarm(struct device *dev,
133				struct device_attribute *devattr, char *buf)
134{
135	u32 eax, edx;
136	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
137	struct platform_data *pdata = dev_get_drvdata(dev);
138	struct temp_data *tdata = pdata->core_data[attr->index];
139
140	rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
141
142	return sprintf(buf, "%d\n", (eax >> 5) & 1);
143}
144
145static ssize_t show_tjmax(struct device *dev,
146			struct device_attribute *devattr, char *buf)
147{
148	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
149	struct platform_data *pdata = dev_get_drvdata(dev);
150
151	return sprintf(buf, "%d\n", pdata->core_data[attr->index]->tjmax);
152}
153
154static ssize_t show_ttarget(struct device *dev,
155				struct device_attribute *devattr, char *buf)
156{
157	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
158	struct platform_data *pdata = dev_get_drvdata(dev);
159
160	return sprintf(buf, "%d\n", pdata->core_data[attr->index]->ttarget);
161}
162
163static ssize_t show_temp(struct device *dev,
164			struct device_attribute *devattr, char *buf)
165{
166	u32 eax, edx;
167	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
168	struct platform_data *pdata = dev_get_drvdata(dev);
169	struct temp_data *tdata = pdata->core_data[attr->index];
170
171	mutex_lock(&tdata->update_lock);
172
173	/* Check whether the time interval has elapsed */
174	if (!tdata->valid || time_after(jiffies, tdata->last_updated + HZ)) {
175		rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
176		/*
177		 * Ignore the valid bit. In all observed cases the register
178		 * value is either low or zero if the valid bit is 0.
179		 * Return it instead of reporting an error which doesn't
180		 * really help at all.
181		 */
182		tdata->temp = tdata->tjmax - ((eax >> 16) & 0x7f) * 1000;
183		tdata->valid = 1;
184		tdata->last_updated = jiffies;
185	}
186
187	mutex_unlock(&tdata->update_lock);
188	return sprintf(buf, "%d\n", tdata->temp);
189}
190
191struct tjmax_pci {
192	unsigned int device;
193	int tjmax;
194};
195
196static const struct tjmax_pci tjmax_pci_table[] = {
197	{ 0x0708, 110000 },	/* CE41x0 (Sodaville ) */
198	{ 0x0c72, 102000 },	/* Atom S1240 (Centerton) */
199	{ 0x0c73, 95000 },	/* Atom S1220 (Centerton) */
200	{ 0x0c75, 95000 },	/* Atom S1260 (Centerton) */
201};
202
203struct tjmax {
204	char const *id;
205	int tjmax;
206};
207
208static const struct tjmax tjmax_table[] = {
209	{ "CPU  230", 100000 },		/* Model 0x1c, stepping 2	*/
210	{ "CPU  330", 125000 },		/* Model 0x1c, stepping 2	*/
211};
212
213struct tjmax_model {
214	u8 model;
215	u8 mask;
216	int tjmax;
217};
218
219#define ANY 0xff
220
221static const struct tjmax_model tjmax_model_table[] = {
222	{ 0x1c, 10, 100000 },	/* D4xx, K4xx, N4xx, D5xx, K5xx, N5xx */
223	{ 0x1c, ANY, 90000 },	/* Z5xx, N2xx, possibly others
224				 * Note: Also matches 230 and 330,
225				 * which are covered by tjmax_table
226				 */
227	{ 0x26, ANY, 90000 },	/* Atom Tunnel Creek (Exx), Lincroft (Z6xx)
228				 * Note: TjMax for E6xxT is 110C, but CPU type
229				 * is undetectable by software
230				 */
231	{ 0x27, ANY, 90000 },	/* Atom Medfield (Z2460) */
232	{ 0x35, ANY, 90000 },	/* Atom Clover Trail/Cloverview (Z27x0) */
233	{ 0x36, ANY, 100000 },	/* Atom Cedar Trail/Cedarview (N2xxx, D2xxx)
234				 * Also matches S12x0 (stepping 9), covered by
235				 * PCI table
236				 */
237};
238
239static int adjust_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev)
240{
241	/* The 100C is default for both mobile and non mobile CPUs */
242
243	int tjmax = 100000;
244	int tjmax_ee = 85000;
245	int usemsr_ee = 1;
246	int err;
247	u32 eax, edx;
248	int i;
249	struct pci_dev *host_bridge = pci_get_bus_and_slot(0, PCI_DEVFN(0, 0));
 
 
 
 
250
251	/*
252	 * Explicit tjmax table entries override heuristics.
253	 * First try PCI host bridge IDs, followed by model ID strings
254	 * and model/stepping information.
255	 */
256	if (host_bridge && host_bridge->vendor == PCI_VENDOR_ID_INTEL) {
257		for (i = 0; i < ARRAY_SIZE(tjmax_pci_table); i++) {
258			if (host_bridge->device == tjmax_pci_table[i].device)
259				return tjmax_pci_table[i].tjmax;
260		}
261	}
262
263	for (i = 0; i < ARRAY_SIZE(tjmax_table); i++) {
264		if (strstr(c->x86_model_id, tjmax_table[i].id))
265			return tjmax_table[i].tjmax;
266	}
267
268	for (i = 0; i < ARRAY_SIZE(tjmax_model_table); i++) {
269		const struct tjmax_model *tm = &tjmax_model_table[i];
270		if (c->x86_model == tm->model &&
271		    (tm->mask == ANY || c->x86_mask == tm->mask))
272			return tm->tjmax;
273	}
274
275	/* Early chips have no MSR for TjMax */
 
 
 
 
 
276
277	if (c->x86_model == 0xf && c->x86_mask < 4)
278		usemsr_ee = 0;
279
280	if (c->x86_model > 0xe && usemsr_ee) {
281		u8 platform_id;
282
283		/*
284		 * Now we can detect the mobile CPU using Intel provided table
285		 * http://softwarecommunity.intel.com/Wiki/Mobility/720.htm
286		 * For Core2 cores, check MSR 0x17, bit 28 1 = Mobile CPU
287		 */
288		err = rdmsr_safe_on_cpu(id, 0x17, &eax, &edx);
289		if (err) {
290			dev_warn(dev,
291				 "Unable to access MSR 0x17, assuming desktop"
292				 " CPU\n");
293			usemsr_ee = 0;
294		} else if (c->x86_model < 0x17 && !(eax & 0x10000000)) {
295			/*
296			 * Trust bit 28 up to Penryn, I could not find any
297			 * documentation on that; if you happen to know
298			 * someone at Intel please ask
299			 */
300			usemsr_ee = 0;
301		} else {
302			/* Platform ID bits 52:50 (EDX starts at bit 32) */
303			platform_id = (edx >> 18) & 0x7;
304
305			/*
306			 * Mobile Penryn CPU seems to be platform ID 7 or 5
307			 * (guesswork)
308			 */
309			if (c->x86_model == 0x17 &&
310			    (platform_id == 5 || platform_id == 7)) {
311				/*
312				 * If MSR EE bit is set, set it to 90 degrees C,
313				 * otherwise 105 degrees C
314				 */
315				tjmax_ee = 90000;
316				tjmax = 105000;
317			}
318		}
319	}
320
321	if (usemsr_ee) {
322		err = rdmsr_safe_on_cpu(id, 0xee, &eax, &edx);
323		if (err) {
324			dev_warn(dev,
325				 "Unable to access MSR 0xEE, for Tjmax, left"
326				 " at default\n");
327		} else if (eax & 0x40000000) {
328			tjmax = tjmax_ee;
329		}
330	} else if (tjmax == 100000) {
331		/*
332		 * If we don't use msr EE it means we are desktop CPU
333		 * (with exeception of Atom)
334		 */
335		dev_warn(dev, "Using relative temperature scale!\n");
336	}
337
338	return tjmax;
339}
340
341static bool cpu_has_tjmax(struct cpuinfo_x86 *c)
342{
343	u8 model = c->x86_model;
344
345	return model > 0xe &&
346	       model != 0x1c &&
347	       model != 0x26 &&
348	       model != 0x27 &&
349	       model != 0x35 &&
350	       model != 0x36;
351}
352
353static int get_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev)
354{
355	int err;
356	u32 eax, edx;
357	u32 val;
358
359	/*
360	 * A new feature of current Intel(R) processors, the
361	 * IA32_TEMPERATURE_TARGET contains the TjMax value
362	 */
363	err = rdmsr_safe_on_cpu(id, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
364	if (err) {
365		if (cpu_has_tjmax(c))
366			dev_warn(dev, "Unable to read TjMax from CPU %u\n", id);
367	} else {
368		val = (eax >> 16) & 0xff;
369		/*
370		 * If the TjMax is not plausible, an assumption
371		 * will be used
372		 */
373		if (val) {
374			dev_dbg(dev, "TjMax is %d degrees C\n", val);
375			return val * 1000;
376		}
377	}
378
379	if (force_tjmax) {
380		dev_notice(dev, "TjMax forced to %d degrees C by user\n",
381			   force_tjmax);
382		return force_tjmax * 1000;
383	}
384
385	/*
386	 * An assumption is made for early CPUs and unreadable MSR.
387	 * NOTE: the calculated value may not be correct.
388	 */
389	return adjust_tjmax(c, id, dev);
390}
391
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
392static int create_core_attrs(struct temp_data *tdata, struct device *dev,
393			     int attr_no)
394{
395	int i;
396	static ssize_t (*const rd_ptr[TOTAL_ATTRS]) (struct device *dev,
397			struct device_attribute *devattr, char *buf) = {
398			show_label, show_crit_alarm, show_temp, show_tjmax,
399			show_ttarget };
400	static const char *const names[TOTAL_ATTRS] = {
401					"temp%d_label", "temp%d_crit_alarm",
402					"temp%d_input", "temp%d_crit",
403					"temp%d_max" };
404
405	for (i = 0; i < tdata->attr_size; i++) {
406		snprintf(tdata->attr_name[i], CORETEMP_NAME_LENGTH, names[i],
407			attr_no);
408		sysfs_attr_init(&tdata->sd_attrs[i].dev_attr.attr);
409		tdata->sd_attrs[i].dev_attr.attr.name = tdata->attr_name[i];
410		tdata->sd_attrs[i].dev_attr.attr.mode = S_IRUGO;
411		tdata->sd_attrs[i].dev_attr.show = rd_ptr[i];
412		tdata->sd_attrs[i].index = attr_no;
413		tdata->attrs[i] = &tdata->sd_attrs[i].dev_attr.attr;
 
 
414	}
415	tdata->attr_group.attrs = tdata->attrs;
416	return sysfs_create_group(&dev->kobj, &tdata->attr_group);
 
 
 
 
417}
418
419
420static int chk_ucode_version(unsigned int cpu)
421{
422	struct cpuinfo_x86 *c = &cpu_data(cpu);
 
 
423
424	/*
425	 * Check if we have problem with errata AE18 of Core processors:
426	 * Readings might stop update when processor visited too deep sleep,
427	 * fixed for stepping D0 (6EC).
428	 */
429	if (c->x86_model == 0xe && c->x86_mask < 0xc && c->microcode < 0x39) {
430		pr_err("Errata AE18 not fixed, update BIOS or microcode of the CPU!\n");
431		return -ENODEV;
 
 
 
 
 
 
 
 
 
 
432	}
433	return 0;
434}
435
436static struct platform_device *coretemp_get_pdev(unsigned int cpu)
437{
438	u16 phys_proc_id = TO_PHYS_ID(cpu);
439	struct pdev_entry *p;
440
441	mutex_lock(&pdev_list_mutex);
442
443	list_for_each_entry(p, &pdev_list, list)
444		if (p->phys_proc_id == phys_proc_id) {
445			mutex_unlock(&pdev_list_mutex);
446			return p->pdev;
447		}
448
449	mutex_unlock(&pdev_list_mutex);
450	return NULL;
451}
452
453static struct temp_data *init_temp_data(unsigned int cpu, int pkg_flag)
454{
455	struct temp_data *tdata;
456
457	tdata = kzalloc(sizeof(struct temp_data), GFP_KERNEL);
458	if (!tdata)
459		return NULL;
460
461	tdata->status_reg = pkg_flag ? MSR_IA32_PACKAGE_THERM_STATUS :
462							MSR_IA32_THERM_STATUS;
463	tdata->is_pkg_data = pkg_flag;
464	tdata->cpu = cpu;
465	tdata->cpu_core_id = TO_CORE_ID(cpu);
466	tdata->attr_size = MAX_CORE_ATTRS;
467	mutex_init(&tdata->update_lock);
468	return tdata;
469}
470
471static int create_core_data(struct platform_device *pdev, unsigned int cpu,
472			    int pkg_flag)
473{
474	struct temp_data *tdata;
475	struct platform_data *pdata = platform_get_drvdata(pdev);
476	struct cpuinfo_x86 *c = &cpu_data(cpu);
477	u32 eax, edx;
478	int err, attr_no;
479
480	/*
481	 * Find attr number for sysfs:
482	 * We map the attr number to core id of the CPU
483	 * The attr number is always core id + 2
484	 * The Pkgtemp will always show up as temp1_*, if available
485	 */
486	attr_no = pkg_flag ? 1 : TO_ATTR_NO(cpu);
487
488	if (attr_no > MAX_CORE_DATA - 1)
489		return -ERANGE;
490
491	/*
492	 * Provide a single set of attributes for all HT siblings of a core
493	 * to avoid duplicate sensors (the processor ID and core ID of all
494	 * HT siblings of a core are the same).
495	 * Skip if a HT sibling of this core is already registered.
496	 * This is not an error.
497	 */
498	if (pdata->core_data[attr_no] != NULL)
499		return 0;
500
501	tdata = init_temp_data(cpu, pkg_flag);
502	if (!tdata)
503		return -ENOMEM;
504
505	/* Test if we can access the status register */
506	err = rdmsr_safe_on_cpu(cpu, tdata->status_reg, &eax, &edx);
507	if (err)
508		goto exit_free;
509
510	/* We can access status register. Get Critical Temperature */
511	tdata->tjmax = get_tjmax(c, cpu, &pdev->dev);
512
513	/*
514	 * Read the still undocumented bits 8:15 of IA32_TEMPERATURE_TARGET.
515	 * The target temperature is available on older CPUs but not in this
516	 * register. Atoms don't have the register at all.
517	 */
518	if (c->x86_model > 0xe && c->x86_model != 0x1c) {
519		err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET,
520					&eax, &edx);
521		if (!err) {
522			tdata->ttarget
523			  = tdata->tjmax - ((eax >> 8) & 0xff) * 1000;
524			tdata->attr_size++;
525		}
526	}
527
528	pdata->core_data[attr_no] = tdata;
529
530	/* Create sysfs interfaces */
531	err = create_core_attrs(tdata, pdata->hwmon_dev, attr_no);
532	if (err)
533		goto exit_free;
534
535	return 0;
536exit_free:
537	pdata->core_data[attr_no] = NULL;
538	kfree(tdata);
539	return err;
540}
541
542static void coretemp_add_core(unsigned int cpu, int pkg_flag)
543{
544	struct platform_device *pdev = coretemp_get_pdev(cpu);
545	int err;
546
547	if (!pdev)
548		return;
549
550	err = create_core_data(pdev, cpu, pkg_flag);
551	if (err)
552		dev_err(&pdev->dev, "Adding Core %u failed\n", cpu);
553}
554
555static void coretemp_remove_core(struct platform_data *pdata,
556				 int indx)
557{
 
558	struct temp_data *tdata = pdata->core_data[indx];
559
560	/* Remove the sysfs attributes */
561	sysfs_remove_group(&pdata->hwmon_dev->kobj, &tdata->attr_group);
 
562
563	kfree(pdata->core_data[indx]);
564	pdata->core_data[indx] = NULL;
565}
566
567static int coretemp_probe(struct platform_device *pdev)
568{
569	struct device *dev = &pdev->dev;
570	struct platform_data *pdata;
 
571
572	/* Initialize the per-package data structures */
573	pdata = devm_kzalloc(dev, sizeof(struct platform_data), GFP_KERNEL);
574	if (!pdata)
575		return -ENOMEM;
576
 
 
 
 
577	pdata->phys_proc_id = pdev->id;
578	platform_set_drvdata(pdev, pdata);
579
580	pdata->hwmon_dev = devm_hwmon_device_register_with_groups(dev, DRVNAME,
581								  pdata, NULL);
582	return PTR_ERR_OR_ZERO(pdata->hwmon_dev);
 
 
 
 
 
 
 
 
 
 
 
583}
584
585static int coretemp_remove(struct platform_device *pdev)
586{
587	struct platform_data *pdata = platform_get_drvdata(pdev);
588	int i;
589
590	for (i = MAX_CORE_DATA - 1; i >= 0; --i)
591		if (pdata->core_data[i])
592			coretemp_remove_core(pdata, i);
593
 
 
 
 
594	return 0;
595}
596
597static struct platform_driver coretemp_driver = {
598	.driver = {
599		.owner = THIS_MODULE,
600		.name = DRVNAME,
601	},
602	.probe = coretemp_probe,
603	.remove = coretemp_remove,
604};
605
606static int coretemp_device_add(unsigned int cpu)
607{
608	int err;
609	struct platform_device *pdev;
610	struct pdev_entry *pdev_entry;
611
612	mutex_lock(&pdev_list_mutex);
613
614	pdev = platform_device_alloc(DRVNAME, TO_PHYS_ID(cpu));
615	if (!pdev) {
616		err = -ENOMEM;
617		pr_err("Device allocation failed\n");
618		goto exit;
619	}
620
621	pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL);
622	if (!pdev_entry) {
623		err = -ENOMEM;
624		goto exit_device_put;
625	}
626
627	err = platform_device_add(pdev);
628	if (err) {
629		pr_err("Device addition failed (%d)\n", err);
630		goto exit_device_free;
631	}
632
633	pdev_entry->pdev = pdev;
634	pdev_entry->phys_proc_id = pdev->id;
635
636	list_add_tail(&pdev_entry->list, &pdev_list);
637	mutex_unlock(&pdev_list_mutex);
638
639	return 0;
640
641exit_device_free:
642	kfree(pdev_entry);
643exit_device_put:
644	platform_device_put(pdev);
645exit:
646	mutex_unlock(&pdev_list_mutex);
647	return err;
648}
649
650static void coretemp_device_remove(unsigned int cpu)
651{
652	struct pdev_entry *p, *n;
653	u16 phys_proc_id = TO_PHYS_ID(cpu);
654
655	mutex_lock(&pdev_list_mutex);
656	list_for_each_entry_safe(p, n, &pdev_list, list) {
657		if (p->phys_proc_id != phys_proc_id)
658			continue;
659		platform_device_unregister(p->pdev);
660		list_del(&p->list);
661		kfree(p);
662	}
663	mutex_unlock(&pdev_list_mutex);
664}
665
666static bool is_any_core_online(struct platform_data *pdata)
667{
668	int i;
669
670	/* Find online cores, except pkgtemp data */
671	for (i = MAX_CORE_DATA - 1; i >= 0; --i) {
672		if (pdata->core_data[i] &&
673			!pdata->core_data[i]->is_pkg_data) {
674			return true;
675		}
676	}
677	return false;
678}
679
680static void get_core_online(unsigned int cpu)
681{
682	struct cpuinfo_x86 *c = &cpu_data(cpu);
683	struct platform_device *pdev = coretemp_get_pdev(cpu);
684	int err;
685
686	/*
687	 * CPUID.06H.EAX[0] indicates whether the CPU has thermal
688	 * sensors. We check this bit only, all the early CPUs
689	 * without thermal sensors will be filtered out.
690	 */
691	if (!cpu_has(c, X86_FEATURE_DTHERM))
692		return;
693
694	if (!pdev) {
695		/* Check the microcode version of the CPU */
696		if (chk_ucode_version(cpu))
697			return;
698
699		/*
700		 * Alright, we have DTS support.
701		 * We are bringing the _first_ core in this pkg
702		 * online. So, initialize per-pkg data structures and
703		 * then bring this core online.
704		 */
705		err = coretemp_device_add(cpu);
706		if (err)
707			return;
708		/*
709		 * Check whether pkgtemp support is available.
710		 * If so, add interfaces for pkgtemp.
711		 */
712		if (cpu_has(c, X86_FEATURE_PTS))
713			coretemp_add_core(cpu, 1);
714	}
715	/*
716	 * Physical CPU device already exists.
717	 * So, just add interfaces for this core.
718	 */
719	coretemp_add_core(cpu, 0);
720}
721
722static void put_core_offline(unsigned int cpu)
723{
724	int i, indx;
725	struct platform_data *pdata;
726	struct platform_device *pdev = coretemp_get_pdev(cpu);
727
728	/* If the physical CPU device does not exist, just return */
729	if (!pdev)
730		return;
731
732	pdata = platform_get_drvdata(pdev);
733
734	indx = TO_ATTR_NO(cpu);
735
736	/* The core id is too big, just return */
737	if (indx > MAX_CORE_DATA - 1)
738		return;
739
740	if (pdata->core_data[indx] && pdata->core_data[indx]->cpu == cpu)
741		coretemp_remove_core(pdata, indx);
742
743	/*
744	 * If a HT sibling of a core is taken offline, but another HT sibling
745	 * of the same core is still online, register the alternate sibling.
746	 * This ensures that exactly one set of attributes is provided as long
747	 * as at least one HT sibling of a core is online.
748	 */
749	for_each_sibling(i, cpu) {
750		if (i != cpu) {
751			get_core_online(i);
752			/*
753			 * Display temperature sensor data for one HT sibling
754			 * per core only, so abort the loop after one such
755			 * sibling has been found.
756			 */
757			break;
758		}
759	}
760	/*
761	 * If all cores in this pkg are offline, remove the device.
762	 * coretemp_device_remove calls unregister_platform_device,
763	 * which in turn calls coretemp_remove. This removes the
764	 * pkgtemp entry and does other clean ups.
765	 */
766	if (!is_any_core_online(pdata))
767		coretemp_device_remove(cpu);
768}
769
770static int coretemp_cpu_callback(struct notifier_block *nfb,
771				 unsigned long action, void *hcpu)
772{
773	unsigned int cpu = (unsigned long) hcpu;
774
775	switch (action) {
776	case CPU_ONLINE:
777	case CPU_DOWN_FAILED:
778		get_core_online(cpu);
779		break;
780	case CPU_DOWN_PREPARE:
781		put_core_offline(cpu);
782		break;
783	}
784	return NOTIFY_OK;
785}
786
787static struct notifier_block coretemp_cpu_notifier __refdata = {
788	.notifier_call = coretemp_cpu_callback,
789};
790
791static const struct x86_cpu_id __initconst coretemp_ids[] = {
792	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_DTHERM },
793	{}
794};
795MODULE_DEVICE_TABLE(x86cpu, coretemp_ids);
796
797static int __init coretemp_init(void)
798{
799	int i, err;
800
801	/*
802	 * CPUID.06H.EAX[0] indicates whether the CPU has thermal
803	 * sensors. We check this bit only, all the early CPUs
804	 * without thermal sensors will be filtered out.
805	 */
806	if (!x86_match_cpu(coretemp_ids))
807		return -ENODEV;
808
809	err = platform_driver_register(&coretemp_driver);
810	if (err)
811		goto exit;
812
813	cpu_notifier_register_begin();
814	for_each_online_cpu(i)
815		get_core_online(i);
816
817#ifndef CONFIG_HOTPLUG_CPU
818	if (list_empty(&pdev_list)) {
819		cpu_notifier_register_done();
820		err = -ENODEV;
821		goto exit_driver_unreg;
822	}
823#endif
824
825	__register_hotcpu_notifier(&coretemp_cpu_notifier);
826	cpu_notifier_register_done();
827	return 0;
828
829#ifndef CONFIG_HOTPLUG_CPU
830exit_driver_unreg:
831	platform_driver_unregister(&coretemp_driver);
832#endif
833exit:
834	return err;
835}
836
837static void __exit coretemp_exit(void)
838{
839	struct pdev_entry *p, *n;
840
841	cpu_notifier_register_begin();
842	__unregister_hotcpu_notifier(&coretemp_cpu_notifier);
843	mutex_lock(&pdev_list_mutex);
844	list_for_each_entry_safe(p, n, &pdev_list, list) {
845		platform_device_unregister(p->pdev);
846		list_del(&p->list);
847		kfree(p);
848	}
849	mutex_unlock(&pdev_list_mutex);
850	cpu_notifier_register_done();
851	platform_driver_unregister(&coretemp_driver);
852}
853
854MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
855MODULE_DESCRIPTION("Intel Core temperature monitor");
856MODULE_LICENSE("GPL");
857
858module_init(coretemp_init)
859module_exit(coretemp_exit)