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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * coretemp.c - Linux kernel module for hardware monitoring
4  *
5  * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
6  *
7  * Inspired from many hwmon drivers
8  */
9 
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/slab.h>
15 #include <linux/jiffies.h>
16 #include <linux/hwmon.h>
17 #include <linux/sysfs.h>
18 #include <linux/hwmon-sysfs.h>
19 #include <linux/err.h>
20 #include <linux/mutex.h>
21 #include <linux/list.h>
22 #include <linux/platform_device.h>
23 #include <linux/cpu.h>
24 #include <linux/smp.h>
25 #include <linux/moduleparam.h>
26 #include <linux/pci.h>
27 #include <asm/msr.h>
28 #include <asm/processor.h>
29 #include <asm/cpu_device_id.h>
30 #include <linux/sched/isolation.h>
31 
32 #define DRVNAME	"coretemp"
33 
34 /*
35  * force_tjmax only matters when TjMax can't be read from the CPU itself.
36  * When set, it replaces the driver's suboptimal heuristic.
37  */
38 static int force_tjmax;
39 module_param_named(tjmax, force_tjmax, int, 0444);
40 MODULE_PARM_DESC(tjmax, "TjMax value in degrees Celsius");
41 
42 #define PKG_SYSFS_ATTR_NO	1	/* Sysfs attribute for package temp */
43 #define BASE_SYSFS_ATTR_NO	2	/* Sysfs Base attr no for coretemp */
44 #define NUM_REAL_CORES		512	/* Number of Real cores per cpu */
45 #define CORETEMP_NAME_LENGTH	28	/* String Length of attrs */
46 #define MAX_CORE_ATTRS		4	/* Maximum no of basic attrs */
47 #define TOTAL_ATTRS		(MAX_CORE_ATTRS + 1)
48 #define MAX_CORE_DATA		(NUM_REAL_CORES + BASE_SYSFS_ATTR_NO)
49 
50 #ifdef CONFIG_SMP
51 #define for_each_sibling(i, cpu) \
52 	for_each_cpu(i, topology_sibling_cpumask(cpu))
53 #else
54 #define for_each_sibling(i, cpu)	for (i = 0; false; )
55 #endif
56 
57 /*
58  * Per-Core Temperature Data
59  * @tjmax: The static tjmax value when tjmax cannot be retrieved from
60  *		IA32_TEMPERATURE_TARGET MSR.
61  * @last_updated: The time when the current temperature value was updated
62  *		earlier (in jiffies).
63  * @cpu_core_id: The CPU Core from which temperature values should be read
64  *		This value is passed as "id" field to rdmsr/wrmsr functions.
65  * @status_reg: One of IA32_THERM_STATUS or IA32_PACKAGE_THERM_STATUS,
66  *		from where the temperature values should be read.
67  * @attr_size:  Total number of pre-core attrs displayed in the sysfs.
68  * @is_pkg_data: If this is 1, the temp_data holds pkgtemp data.
69  *		Otherwise, temp_data holds coretemp data.
70  */
71 struct temp_data {
72 	int temp;
73 	int tjmax;
74 	unsigned long last_updated;
75 	unsigned int cpu;
76 	u32 cpu_core_id;
77 	u32 status_reg;
78 	int attr_size;
79 	bool is_pkg_data;
80 	struct sensor_device_attribute sd_attrs[TOTAL_ATTRS];
81 	char attr_name[TOTAL_ATTRS][CORETEMP_NAME_LENGTH];
82 	struct attribute *attrs[TOTAL_ATTRS + 1];
83 	struct attribute_group attr_group;
84 	struct mutex update_lock;
85 };
86 
87 /* Platform Data per Physical CPU */
88 struct platform_data {
89 	struct device		*hwmon_dev;
90 	u16			pkg_id;
91 	u16			cpu_map[NUM_REAL_CORES];
92 	struct ida		ida;
93 	struct cpumask		cpumask;
94 	struct temp_data	*core_data[MAX_CORE_DATA];
95 	struct device_attribute name_attr;
96 };
97 
98 struct tjmax_pci {
99 	unsigned int device;
100 	int tjmax;
101 };
102 
103 static const struct tjmax_pci tjmax_pci_table[] = {
104 	{ 0x0708, 110000 },	/* CE41x0 (Sodaville ) */
105 	{ 0x0c72, 102000 },	/* Atom S1240 (Centerton) */
106 	{ 0x0c73, 95000 },	/* Atom S1220 (Centerton) */
107 	{ 0x0c75, 95000 },	/* Atom S1260 (Centerton) */
108 };
109 
110 struct tjmax {
111 	char const *id;
112 	int tjmax;
113 };
114 
115 static const struct tjmax tjmax_table[] = {
116 	{ "CPU  230", 100000 },		/* Model 0x1c, stepping 2	*/
117 	{ "CPU  330", 125000 },		/* Model 0x1c, stepping 2	*/
118 };
119 
120 struct tjmax_model {
121 	u8 model;
122 	u8 mask;
123 	int tjmax;
124 };
125 
126 #define ANY 0xff
127 
128 static const struct tjmax_model tjmax_model_table[] = {
129 	{ 0x1c, 10, 100000 },	/* D4xx, K4xx, N4xx, D5xx, K5xx, N5xx */
130 	{ 0x1c, ANY, 90000 },	/* Z5xx, N2xx, possibly others
131 				 * Note: Also matches 230 and 330,
132 				 * which are covered by tjmax_table
133 				 */
134 	{ 0x26, ANY, 90000 },	/* Atom Tunnel Creek (Exx), Lincroft (Z6xx)
135 				 * Note: TjMax for E6xxT is 110C, but CPU type
136 				 * is undetectable by software
137 				 */
138 	{ 0x27, ANY, 90000 },	/* Atom Medfield (Z2460) */
139 	{ 0x35, ANY, 90000 },	/* Atom Clover Trail/Cloverview (Z27x0) */
140 	{ 0x36, ANY, 100000 },	/* Atom Cedar Trail/Cedarview (N2xxx, D2xxx)
141 				 * Also matches S12x0 (stepping 9), covered by
142 				 * PCI table
143 				 */
144 };
145 
adjust_tjmax(struct cpuinfo_x86 * c,u32 id,struct device * dev)146 static int adjust_tjmax(struct cpuinfo_x86 *c, u32 id, struct device *dev)
147 {
148 	/* The 100C is default for both mobile and non mobile CPUs */
149 
150 	int tjmax = 100000;
151 	int tjmax_ee = 85000;
152 	int usemsr_ee = 1;
153 	int err;
154 	u32 eax, edx;
155 	int i;
156 	u16 devfn = PCI_DEVFN(0, 0);
157 	struct pci_dev *host_bridge = pci_get_domain_bus_and_slot(0, 0, devfn);
158 
159 	/*
160 	 * Explicit tjmax table entries override heuristics.
161 	 * First try PCI host bridge IDs, followed by model ID strings
162 	 * and model/stepping information.
163 	 */
164 	if (host_bridge && host_bridge->vendor == PCI_VENDOR_ID_INTEL) {
165 		for (i = 0; i < ARRAY_SIZE(tjmax_pci_table); i++) {
166 			if (host_bridge->device == tjmax_pci_table[i].device) {
167 				pci_dev_put(host_bridge);
168 				return tjmax_pci_table[i].tjmax;
169 			}
170 		}
171 	}
172 	pci_dev_put(host_bridge);
173 
174 	for (i = 0; i < ARRAY_SIZE(tjmax_table); i++) {
175 		if (strstr(c->x86_model_id, tjmax_table[i].id))
176 			return tjmax_table[i].tjmax;
177 	}
178 
179 	for (i = 0; i < ARRAY_SIZE(tjmax_model_table); i++) {
180 		const struct tjmax_model *tm = &tjmax_model_table[i];
181 		if (c->x86_model == tm->model &&
182 		    (tm->mask == ANY || c->x86_stepping == tm->mask))
183 			return tm->tjmax;
184 	}
185 
186 	/* Early chips have no MSR for TjMax */
187 
188 	if (c->x86_model == 0xf && c->x86_stepping < 4)
189 		usemsr_ee = 0;
190 
191 	if (c->x86_model > 0xe && usemsr_ee) {
192 		u8 platform_id;
193 
194 		/*
195 		 * Now we can detect the mobile CPU using Intel provided table
196 		 * http://softwarecommunity.intel.com/Wiki/Mobility/720.htm
197 		 * For Core2 cores, check MSR 0x17, bit 28 1 = Mobile CPU
198 		 */
199 		err = rdmsr_safe_on_cpu(id, 0x17, &eax, &edx);
200 		if (err) {
201 			dev_warn(dev,
202 				 "Unable to access MSR 0x17, assuming desktop"
203 				 " CPU\n");
204 			usemsr_ee = 0;
205 		} else if (c->x86_model < 0x17 && !(eax & 0x10000000)) {
206 			/*
207 			 * Trust bit 28 up to Penryn, I could not find any
208 			 * documentation on that; if you happen to know
209 			 * someone at Intel please ask
210 			 */
211 			usemsr_ee = 0;
212 		} else {
213 			/* Platform ID bits 52:50 (EDX starts at bit 32) */
214 			platform_id = (edx >> 18) & 0x7;
215 
216 			/*
217 			 * Mobile Penryn CPU seems to be platform ID 7 or 5
218 			 * (guesswork)
219 			 */
220 			if (c->x86_model == 0x17 &&
221 			    (platform_id == 5 || platform_id == 7)) {
222 				/*
223 				 * If MSR EE bit is set, set it to 90 degrees C,
224 				 * otherwise 105 degrees C
225 				 */
226 				tjmax_ee = 90000;
227 				tjmax = 105000;
228 			}
229 		}
230 	}
231 
232 	if (usemsr_ee) {
233 		err = rdmsr_safe_on_cpu(id, 0xee, &eax, &edx);
234 		if (err) {
235 			dev_warn(dev,
236 				 "Unable to access MSR 0xEE, for Tjmax, left"
237 				 " at default\n");
238 		} else if (eax & 0x40000000) {
239 			tjmax = tjmax_ee;
240 		}
241 	} else if (tjmax == 100000) {
242 		/*
243 		 * If we don't use msr EE it means we are desktop CPU
244 		 * (with exeception of Atom)
245 		 */
246 		dev_warn(dev, "Using relative temperature scale!\n");
247 	}
248 
249 	return tjmax;
250 }
251 
cpu_has_tjmax(struct cpuinfo_x86 * c)252 static bool cpu_has_tjmax(struct cpuinfo_x86 *c)
253 {
254 	u8 model = c->x86_model;
255 
256 	return model > 0xe &&
257 	       model != 0x1c &&
258 	       model != 0x26 &&
259 	       model != 0x27 &&
260 	       model != 0x35 &&
261 	       model != 0x36;
262 }
263 
get_tjmax(struct temp_data * tdata,struct device * dev)264 static int get_tjmax(struct temp_data *tdata, struct device *dev)
265 {
266 	struct cpuinfo_x86 *c = &cpu_data(tdata->cpu);
267 	int err;
268 	u32 eax, edx;
269 	u32 val;
270 
271 	/* use static tjmax once it is set */
272 	if (tdata->tjmax)
273 		return tdata->tjmax;
274 
275 	/*
276 	 * A new feature of current Intel(R) processors, the
277 	 * IA32_TEMPERATURE_TARGET contains the TjMax value
278 	 */
279 	err = rdmsr_safe_on_cpu(tdata->cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
280 	if (err) {
281 		if (cpu_has_tjmax(c))
282 			dev_warn(dev, "Unable to read TjMax from CPU %u\n", tdata->cpu);
283 	} else {
284 		val = (eax >> 16) & 0xff;
285 		if (val)
286 			return val * 1000;
287 	}
288 
289 	if (force_tjmax) {
290 		dev_notice(dev, "TjMax forced to %d degrees C by user\n",
291 			   force_tjmax);
292 		tdata->tjmax = force_tjmax * 1000;
293 	} else {
294 		/*
295 		 * An assumption is made for early CPUs and unreadable MSR.
296 		 * NOTE: the calculated value may not be correct.
297 		 */
298 		tdata->tjmax = adjust_tjmax(c, tdata->cpu, dev);
299 	}
300 	return tdata->tjmax;
301 }
302 
get_ttarget(struct temp_data * tdata,struct device * dev)303 static int get_ttarget(struct temp_data *tdata, struct device *dev)
304 {
305 	u32 eax, edx;
306 	int tjmax, ttarget_offset, ret;
307 
308 	/*
309 	 * ttarget is valid only if tjmax can be retrieved from
310 	 * MSR_IA32_TEMPERATURE_TARGET
311 	 */
312 	if (tdata->tjmax)
313 		return -ENODEV;
314 
315 	ret = rdmsr_safe_on_cpu(tdata->cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
316 	if (ret)
317 		return ret;
318 
319 	tjmax = (eax >> 16) & 0xff;
320 
321 	/* Read the still undocumented bits 8:15 of IA32_TEMPERATURE_TARGET. */
322 	ttarget_offset = (eax >> 8) & 0xff;
323 
324 	return (tjmax - ttarget_offset) * 1000;
325 }
326 
327 /* Keep track of how many zone pointers we allocated in init() */
328 static int max_zones __read_mostly;
329 /* Array of zone pointers. Serialized by cpu hotplug lock */
330 static struct platform_device **zone_devices;
331 
show_label(struct device * dev,struct device_attribute * devattr,char * buf)332 static ssize_t show_label(struct device *dev,
333 				struct device_attribute *devattr, char *buf)
334 {
335 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
336 	struct platform_data *pdata = dev_get_drvdata(dev);
337 	struct temp_data *tdata = pdata->core_data[attr->index];
338 
339 	if (tdata->is_pkg_data)
340 		return sprintf(buf, "Package id %u\n", pdata->pkg_id);
341 
342 	return sprintf(buf, "Core %u\n", tdata->cpu_core_id);
343 }
344 
show_crit_alarm(struct device * dev,struct device_attribute * devattr,char * buf)345 static ssize_t show_crit_alarm(struct device *dev,
346 				struct device_attribute *devattr, char *buf)
347 {
348 	u32 eax, edx;
349 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
350 	struct platform_data *pdata = dev_get_drvdata(dev);
351 	struct temp_data *tdata = pdata->core_data[attr->index];
352 
353 	mutex_lock(&tdata->update_lock);
354 	rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
355 	mutex_unlock(&tdata->update_lock);
356 
357 	return sprintf(buf, "%d\n", (eax >> 5) & 1);
358 }
359 
show_tjmax(struct device * dev,struct device_attribute * devattr,char * buf)360 static ssize_t show_tjmax(struct device *dev,
361 			struct device_attribute *devattr, char *buf)
362 {
363 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
364 	struct platform_data *pdata = dev_get_drvdata(dev);
365 	struct temp_data *tdata = pdata->core_data[attr->index];
366 	int tjmax;
367 
368 	mutex_lock(&tdata->update_lock);
369 	tjmax = get_tjmax(tdata, dev);
370 	mutex_unlock(&tdata->update_lock);
371 
372 	return sprintf(buf, "%d\n", tjmax);
373 }
374 
show_ttarget(struct device * dev,struct device_attribute * devattr,char * buf)375 static ssize_t show_ttarget(struct device *dev,
376 				struct device_attribute *devattr, char *buf)
377 {
378 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
379 	struct platform_data *pdata = dev_get_drvdata(dev);
380 	struct temp_data *tdata = pdata->core_data[attr->index];
381 	int ttarget;
382 
383 	mutex_lock(&tdata->update_lock);
384 	ttarget = get_ttarget(tdata, dev);
385 	mutex_unlock(&tdata->update_lock);
386 
387 	if (ttarget < 0)
388 		return ttarget;
389 	return sprintf(buf, "%d\n", ttarget);
390 }
391 
show_temp(struct device * dev,struct device_attribute * devattr,char * buf)392 static ssize_t show_temp(struct device *dev,
393 			struct device_attribute *devattr, char *buf)
394 {
395 	u32 eax, edx;
396 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
397 	struct platform_data *pdata = dev_get_drvdata(dev);
398 	struct temp_data *tdata = pdata->core_data[attr->index];
399 	int tjmax;
400 
401 	mutex_lock(&tdata->update_lock);
402 
403 	tjmax = get_tjmax(tdata, dev);
404 	/* Check whether the time interval has elapsed */
405 	if (time_after(jiffies, tdata->last_updated + HZ)) {
406 		rdmsr_on_cpu(tdata->cpu, tdata->status_reg, &eax, &edx);
407 		/*
408 		 * Ignore the valid bit. In all observed cases the register
409 		 * value is either low or zero if the valid bit is 0.
410 		 * Return it instead of reporting an error which doesn't
411 		 * really help at all.
412 		 */
413 		tdata->temp = tjmax - ((eax >> 16) & 0x7f) * 1000;
414 		tdata->last_updated = jiffies;
415 	}
416 
417 	mutex_unlock(&tdata->update_lock);
418 	return sprintf(buf, "%d\n", tdata->temp);
419 }
420 
create_core_attrs(struct temp_data * tdata,struct device * dev,int index)421 static int create_core_attrs(struct temp_data *tdata, struct device *dev,
422 			     int index)
423 {
424 	int i;
425 	static ssize_t (*const rd_ptr[TOTAL_ATTRS]) (struct device *dev,
426 			struct device_attribute *devattr, char *buf) = {
427 			show_label, show_crit_alarm, show_temp, show_tjmax,
428 			show_ttarget };
429 	static const char *const suffixes[TOTAL_ATTRS] = {
430 		"label", "crit_alarm", "input", "crit", "max"
431 	};
432 
433 	for (i = 0; i < tdata->attr_size; i++) {
434 		/*
435 		 * We map the attr number to core id of the CPU
436 		 * The attr number is always core id + 2
437 		 * The Pkgtemp will always show up as temp1_*, if available
438 		 */
439 		int attr_no = tdata->is_pkg_data ? 1 : tdata->cpu_core_id + 2;
440 
441 		snprintf(tdata->attr_name[i], CORETEMP_NAME_LENGTH,
442 			 "temp%d_%s", attr_no, suffixes[i]);
443 		sysfs_attr_init(&tdata->sd_attrs[i].dev_attr.attr);
444 		tdata->sd_attrs[i].dev_attr.attr.name = tdata->attr_name[i];
445 		tdata->sd_attrs[i].dev_attr.attr.mode = 0444;
446 		tdata->sd_attrs[i].dev_attr.show = rd_ptr[i];
447 		tdata->sd_attrs[i].index = index;
448 		tdata->attrs[i] = &tdata->sd_attrs[i].dev_attr.attr;
449 	}
450 	tdata->attr_group.attrs = tdata->attrs;
451 	return sysfs_create_group(&dev->kobj, &tdata->attr_group);
452 }
453 
454 
chk_ucode_version(unsigned int cpu)455 static int chk_ucode_version(unsigned int cpu)
456 {
457 	struct cpuinfo_x86 *c = &cpu_data(cpu);
458 
459 	/*
460 	 * Check if we have problem with errata AE18 of Core processors:
461 	 * Readings might stop update when processor visited too deep sleep,
462 	 * fixed for stepping D0 (6EC).
463 	 */
464 	if (c->x86_model == 0xe && c->x86_stepping < 0xc && c->microcode < 0x39) {
465 		pr_err("Errata AE18 not fixed, update BIOS or microcode of the CPU!\n");
466 		return -ENODEV;
467 	}
468 	return 0;
469 }
470 
coretemp_get_pdev(unsigned int cpu)471 static struct platform_device *coretemp_get_pdev(unsigned int cpu)
472 {
473 	int id = topology_logical_die_id(cpu);
474 
475 	if (id >= 0 && id < max_zones)
476 		return zone_devices[id];
477 	return NULL;
478 }
479 
init_temp_data(unsigned int cpu,int pkg_flag)480 static struct temp_data *init_temp_data(unsigned int cpu, int pkg_flag)
481 {
482 	struct temp_data *tdata;
483 
484 	tdata = kzalloc(sizeof(struct temp_data), GFP_KERNEL);
485 	if (!tdata)
486 		return NULL;
487 
488 	tdata->status_reg = pkg_flag ? MSR_IA32_PACKAGE_THERM_STATUS :
489 							MSR_IA32_THERM_STATUS;
490 	tdata->is_pkg_data = pkg_flag;
491 	tdata->cpu = cpu;
492 	tdata->cpu_core_id = topology_core_id(cpu);
493 	tdata->attr_size = MAX_CORE_ATTRS;
494 	mutex_init(&tdata->update_lock);
495 	return tdata;
496 }
497 
create_core_data(struct platform_device * pdev,unsigned int cpu,int pkg_flag)498 static int create_core_data(struct platform_device *pdev, unsigned int cpu,
499 			    int pkg_flag)
500 {
501 	struct temp_data *tdata;
502 	struct platform_data *pdata = platform_get_drvdata(pdev);
503 	struct cpuinfo_x86 *c = &cpu_data(cpu);
504 	u32 eax, edx;
505 	int err, index;
506 
507 	if (!housekeeping_cpu(cpu, HK_TYPE_MISC))
508 		return 0;
509 
510 	/*
511 	 * Get the index of tdata in pdata->core_data[]
512 	 * tdata for package: pdata->core_data[1]
513 	 * tdata for core: pdata->core_data[2] .. pdata->core_data[NUM_REAL_CORES + 1]
514 	 */
515 	if (pkg_flag) {
516 		index = PKG_SYSFS_ATTR_NO;
517 	} else {
518 		index = ida_alloc_max(&pdata->ida, NUM_REAL_CORES - 1, GFP_KERNEL);
519 		if (index < 0)
520 			return index;
521 
522 		pdata->cpu_map[index] = topology_core_id(cpu);
523 		index += BASE_SYSFS_ATTR_NO;
524 	}
525 
526 	tdata = init_temp_data(cpu, pkg_flag);
527 	if (!tdata) {
528 		err = -ENOMEM;
529 		goto ida_free;
530 	}
531 
532 	/* Test if we can access the status register */
533 	err = rdmsr_safe_on_cpu(cpu, tdata->status_reg, &eax, &edx);
534 	if (err)
535 		goto exit_free;
536 
537 	/* Make sure tdata->tjmax is a valid indicator for dynamic/static tjmax */
538 	get_tjmax(tdata, &pdev->dev);
539 
540 	/*
541 	 * The target temperature is available on older CPUs but not in the
542 	 * MSR_IA32_TEMPERATURE_TARGET register. Atoms don't have the register
543 	 * at all.
544 	 */
545 	if (c->x86_model > 0xe && c->x86_model != 0x1c)
546 		if (get_ttarget(tdata, &pdev->dev) >= 0)
547 			tdata->attr_size++;
548 
549 	pdata->core_data[index] = tdata;
550 
551 	/* Create sysfs interfaces */
552 	err = create_core_attrs(tdata, pdata->hwmon_dev, index);
553 	if (err)
554 		goto exit_free;
555 
556 	return 0;
557 exit_free:
558 	pdata->core_data[index] = NULL;
559 	kfree(tdata);
560 ida_free:
561 	if (!pkg_flag)
562 		ida_free(&pdata->ida, index - BASE_SYSFS_ATTR_NO);
563 	return err;
564 }
565 
566 static void
coretemp_add_core(struct platform_device * pdev,unsigned int cpu,int pkg_flag)567 coretemp_add_core(struct platform_device *pdev, unsigned int cpu, int pkg_flag)
568 {
569 	if (create_core_data(pdev, cpu, pkg_flag))
570 		dev_err(&pdev->dev, "Adding Core %u failed\n", cpu);
571 }
572 
coretemp_remove_core(struct platform_data * pdata,int indx)573 static void coretemp_remove_core(struct platform_data *pdata, int indx)
574 {
575 	struct temp_data *tdata = pdata->core_data[indx];
576 
577 	/* if we errored on add then this is already gone */
578 	if (!tdata)
579 		return;
580 
581 	/* Remove the sysfs attributes */
582 	sysfs_remove_group(&pdata->hwmon_dev->kobj, &tdata->attr_group);
583 
584 	kfree(pdata->core_data[indx]);
585 	pdata->core_data[indx] = NULL;
586 
587 	if (indx >= BASE_SYSFS_ATTR_NO)
588 		ida_free(&pdata->ida, indx - BASE_SYSFS_ATTR_NO);
589 }
590 
coretemp_device_add(int zoneid)591 static int coretemp_device_add(int zoneid)
592 {
593 	struct platform_device *pdev;
594 	struct platform_data *pdata;
595 	int err;
596 
597 	/* Initialize the per-zone data structures */
598 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
599 	if (!pdata)
600 		return -ENOMEM;
601 
602 	pdata->pkg_id = zoneid;
603 	ida_init(&pdata->ida);
604 
605 	pdev = platform_device_alloc(DRVNAME, zoneid);
606 	if (!pdev) {
607 		err = -ENOMEM;
608 		goto err_free_pdata;
609 	}
610 
611 	err = platform_device_add(pdev);
612 	if (err)
613 		goto err_put_dev;
614 
615 	platform_set_drvdata(pdev, pdata);
616 	zone_devices[zoneid] = pdev;
617 	return 0;
618 
619 err_put_dev:
620 	platform_device_put(pdev);
621 err_free_pdata:
622 	kfree(pdata);
623 	return err;
624 }
625 
coretemp_device_remove(int zoneid)626 static void coretemp_device_remove(int zoneid)
627 {
628 	struct platform_device *pdev = zone_devices[zoneid];
629 	struct platform_data *pdata = platform_get_drvdata(pdev);
630 
631 	ida_destroy(&pdata->ida);
632 	kfree(pdata);
633 	platform_device_unregister(pdev);
634 }
635 
coretemp_cpu_online(unsigned int cpu)636 static int coretemp_cpu_online(unsigned int cpu)
637 {
638 	struct platform_device *pdev = coretemp_get_pdev(cpu);
639 	struct cpuinfo_x86 *c = &cpu_data(cpu);
640 	struct platform_data *pdata;
641 
642 	/*
643 	 * Don't execute this on resume as the offline callback did
644 	 * not get executed on suspend.
645 	 */
646 	if (cpuhp_tasks_frozen)
647 		return 0;
648 
649 	/*
650 	 * CPUID.06H.EAX[0] indicates whether the CPU has thermal
651 	 * sensors. We check this bit only, all the early CPUs
652 	 * without thermal sensors will be filtered out.
653 	 */
654 	if (!cpu_has(c, X86_FEATURE_DTHERM))
655 		return -ENODEV;
656 
657 	pdata = platform_get_drvdata(pdev);
658 	if (!pdata->hwmon_dev) {
659 		struct device *hwmon;
660 
661 		/* Check the microcode version of the CPU */
662 		if (chk_ucode_version(cpu))
663 			return -EINVAL;
664 
665 		/*
666 		 * Alright, we have DTS support.
667 		 * We are bringing the _first_ core in this pkg
668 		 * online. So, initialize per-pkg data structures and
669 		 * then bring this core online.
670 		 */
671 		hwmon = hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
672 							  pdata, NULL);
673 		if (IS_ERR(hwmon))
674 			return PTR_ERR(hwmon);
675 		pdata->hwmon_dev = hwmon;
676 
677 		/*
678 		 * Check whether pkgtemp support is available.
679 		 * If so, add interfaces for pkgtemp.
680 		 */
681 		if (cpu_has(c, X86_FEATURE_PTS))
682 			coretemp_add_core(pdev, cpu, 1);
683 	}
684 
685 	/*
686 	 * Check whether a thread sibling is already online. If not add the
687 	 * interface for this CPU core.
688 	 */
689 	if (!cpumask_intersects(&pdata->cpumask, topology_sibling_cpumask(cpu)))
690 		coretemp_add_core(pdev, cpu, 0);
691 
692 	cpumask_set_cpu(cpu, &pdata->cpumask);
693 	return 0;
694 }
695 
coretemp_cpu_offline(unsigned int cpu)696 static int coretemp_cpu_offline(unsigned int cpu)
697 {
698 	struct platform_device *pdev = coretemp_get_pdev(cpu);
699 	struct platform_data *pd;
700 	struct temp_data *tdata;
701 	int i, indx = -1, target;
702 
703 	/* No need to tear down any interfaces for suspend */
704 	if (cpuhp_tasks_frozen)
705 		return 0;
706 
707 	/* If the physical CPU device does not exist, just return */
708 	pd = platform_get_drvdata(pdev);
709 	if (!pd->hwmon_dev)
710 		return 0;
711 
712 	for (i = 0; i < NUM_REAL_CORES; i++) {
713 		if (pd->cpu_map[i] == topology_core_id(cpu)) {
714 			indx = i + BASE_SYSFS_ATTR_NO;
715 			break;
716 		}
717 	}
718 
719 	/* Too many cores and this core is not populated, just return */
720 	if (indx < 0)
721 		return 0;
722 
723 	tdata = pd->core_data[indx];
724 
725 	cpumask_clear_cpu(cpu, &pd->cpumask);
726 
727 	/*
728 	 * If this is the last thread sibling, remove the CPU core
729 	 * interface, If there is still a sibling online, transfer the
730 	 * target cpu of that core interface to it.
731 	 */
732 	target = cpumask_any_and(&pd->cpumask, topology_sibling_cpumask(cpu));
733 	if (target >= nr_cpu_ids) {
734 		coretemp_remove_core(pd, indx);
735 	} else if (tdata && tdata->cpu == cpu) {
736 		mutex_lock(&tdata->update_lock);
737 		tdata->cpu = target;
738 		mutex_unlock(&tdata->update_lock);
739 	}
740 
741 	/*
742 	 * If all cores in this pkg are offline, remove the interface.
743 	 */
744 	tdata = pd->core_data[PKG_SYSFS_ATTR_NO];
745 	if (cpumask_empty(&pd->cpumask)) {
746 		if (tdata)
747 			coretemp_remove_core(pd, PKG_SYSFS_ATTR_NO);
748 		hwmon_device_unregister(pd->hwmon_dev);
749 		pd->hwmon_dev = NULL;
750 		return 0;
751 	}
752 
753 	/*
754 	 * Check whether this core is the target for the package
755 	 * interface. We need to assign it to some other cpu.
756 	 */
757 	if (tdata && tdata->cpu == cpu) {
758 		target = cpumask_first(&pd->cpumask);
759 		mutex_lock(&tdata->update_lock);
760 		tdata->cpu = target;
761 		mutex_unlock(&tdata->update_lock);
762 	}
763 	return 0;
764 }
765 static const struct x86_cpu_id __initconst coretemp_ids[] = {
766 	X86_MATCH_VENDOR_FEATURE(INTEL, X86_FEATURE_DTHERM, NULL),
767 	{}
768 };
769 MODULE_DEVICE_TABLE(x86cpu, coretemp_ids);
770 
771 static enum cpuhp_state coretemp_hp_online;
772 
coretemp_init(void)773 static int __init coretemp_init(void)
774 {
775 	int i, err;
776 
777 	/*
778 	 * CPUID.06H.EAX[0] indicates whether the CPU has thermal
779 	 * sensors. We check this bit only, all the early CPUs
780 	 * without thermal sensors will be filtered out.
781 	 */
782 	if (!x86_match_cpu(coretemp_ids))
783 		return -ENODEV;
784 
785 	max_zones = topology_max_packages() * topology_max_die_per_package();
786 	zone_devices = kcalloc(max_zones, sizeof(struct platform_device *),
787 			      GFP_KERNEL);
788 	if (!zone_devices)
789 		return -ENOMEM;
790 
791 	for (i = 0; i < max_zones; i++) {
792 		err = coretemp_device_add(i);
793 		if (err)
794 			goto outzone;
795 	}
796 
797 	err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hwmon/coretemp:online",
798 				coretemp_cpu_online, coretemp_cpu_offline);
799 	if (err < 0)
800 		goto outzone;
801 	coretemp_hp_online = err;
802 	return 0;
803 
804 outzone:
805 	while (i--)
806 		coretemp_device_remove(i);
807 	kfree(zone_devices);
808 	return err;
809 }
module_init(coretemp_init)810 module_init(coretemp_init)
811 
812 static void __exit coretemp_exit(void)
813 {
814 	int i;
815 
816 	cpuhp_remove_state(coretemp_hp_online);
817 	for (i = 0; i < max_zones; i++)
818 		coretemp_device_remove(i);
819 	kfree(zone_devices);
820 }
821 module_exit(coretemp_exit)
822 
823 MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
824 MODULE_DESCRIPTION("Intel Core temperature monitor");
825 MODULE_LICENSE("GPL");
826