xref: /openbmc/linux/drivers/hwmon/peci/cputemp.c (revision 2bad466c) 
1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright (c) 2018-2021 Intel Corporation
3 
4 #include <linux/auxiliary_bus.h>
5 #include <linux/bitfield.h>
6 #include <linux/bitops.h>
7 #include <linux/hwmon.h>
8 #include <linux/jiffies.h>
9 #include <linux/module.h>
10 #include <linux/peci.h>
11 #include <linux/peci-cpu.h>
12 #include <linux/units.h>
13 
14 #include "common.h"
15 
16 #define CORE_NUMS_MAX		64
17 
18 #define BASE_CHANNEL_NUMS	5
19 #define CPUTEMP_CHANNEL_NUMS	(BASE_CHANNEL_NUMS + CORE_NUMS_MAX)
20 
21 #define TEMP_TARGET_FAN_TEMP_MASK	GENMASK(15, 8)
22 #define TEMP_TARGET_REF_TEMP_MASK	GENMASK(23, 16)
23 #define TEMP_TARGET_TJ_OFFSET_MASK	GENMASK(29, 24)
24 
25 #define DTS_MARGIN_MASK		GENMASK(15, 0)
26 #define PCS_MODULE_TEMP_MASK	GENMASK(15, 0)
27 
28 struct resolved_cores_reg {
29 	u8 bus;
30 	u8 dev;
31 	u8 func;
32 	u8 offset;
33 };
34 
35 struct cpu_info {
36 	struct resolved_cores_reg *reg;
37 	u8 min_peci_revision;
38 	s32 (*thermal_margin_to_millidegree)(u16 val);
39 };
40 
41 struct peci_temp_target {
42 	s32 tcontrol;
43 	s32 tthrottle;
44 	s32 tjmax;
45 	struct peci_sensor_state state;
46 };
47 
48 enum peci_temp_target_type {
49 	tcontrol_type,
50 	tthrottle_type,
51 	tjmax_type,
52 	crit_hyst_type,
53 };
54 
55 struct peci_cputemp {
56 	struct peci_device *peci_dev;
57 	struct device *dev;
58 	const char *name;
59 	const struct cpu_info *gen_info;
60 	struct {
61 		struct peci_temp_target target;
62 		struct peci_sensor_data die;
63 		struct peci_sensor_data dts;
64 		struct peci_sensor_data core[CORE_NUMS_MAX];
65 	} temp;
66 	const char **coretemp_label;
67 	DECLARE_BITMAP(core_mask, CORE_NUMS_MAX);
68 };
69 
70 enum cputemp_channels {
71 	channel_die,
72 	channel_dts,
73 	channel_tcontrol,
74 	channel_tthrottle,
75 	channel_tjmax,
76 	channel_core,
77 };
78 
79 static const char * const cputemp_label[BASE_CHANNEL_NUMS] = {
80 	"Die",
81 	"DTS",
82 	"Tcontrol",
83 	"Tthrottle",
84 	"Tjmax",
85 };
86 
87 static int update_temp_target(struct peci_cputemp *priv)
88 {
89 	s32 tthrottle_offset, tcontrol_margin;
90 	u32 pcs;
91 	int ret;
92 
93 	if (!peci_sensor_need_update(&priv->temp.target.state))
94 		return 0;
95 
96 	ret = peci_pcs_read(priv->peci_dev, PECI_PCS_TEMP_TARGET, 0, &pcs);
97 	if (ret)
98 		return ret;
99 
100 	priv->temp.target.tjmax =
101 		FIELD_GET(TEMP_TARGET_REF_TEMP_MASK, pcs) * MILLIDEGREE_PER_DEGREE;
102 
103 	tcontrol_margin = FIELD_GET(TEMP_TARGET_FAN_TEMP_MASK, pcs);
104 	tcontrol_margin = sign_extend32(tcontrol_margin, 7) * MILLIDEGREE_PER_DEGREE;
105 	priv->temp.target.tcontrol = priv->temp.target.tjmax - tcontrol_margin;
106 
107 	tthrottle_offset = FIELD_GET(TEMP_TARGET_TJ_OFFSET_MASK, pcs) * MILLIDEGREE_PER_DEGREE;
108 	priv->temp.target.tthrottle = priv->temp.target.tjmax - tthrottle_offset;
109 
110 	peci_sensor_mark_updated(&priv->temp.target.state);
111 
112 	return 0;
113 }
114 
115 static int get_temp_target(struct peci_cputemp *priv, enum peci_temp_target_type type, long *val)
116 {
117 	int ret;
118 
119 	mutex_lock(&priv->temp.target.state.lock);
120 
121 	ret = update_temp_target(priv);
122 	if (ret)
123 		goto unlock;
124 
125 	switch (type) {
126 	case tcontrol_type:
127 		*val = priv->temp.target.tcontrol;
128 		break;
129 	case tthrottle_type:
130 		*val = priv->temp.target.tthrottle;
131 		break;
132 	case tjmax_type:
133 		*val = priv->temp.target.tjmax;
134 		break;
135 	case crit_hyst_type:
136 		*val = priv->temp.target.tjmax - priv->temp.target.tcontrol;
137 		break;
138 	default:
139 		ret = -EOPNOTSUPP;
140 		break;
141 	}
142 unlock:
143 	mutex_unlock(&priv->temp.target.state.lock);
144 
145 	return ret;
146 }
147 
148 /*
149  * Error codes:
150  *   0x8000: General sensor error
151  *   0x8001: Reserved
152  *   0x8002: Underflow on reading value
153  *   0x8003-0x81ff: Reserved
154  */
155 static bool dts_valid(u16 val)
156 {
157 	return val < 0x8000 || val > 0x81ff;
158 }
159 
160 /*
161  * Processors return a value of DTS reading in S10.6 fixed point format
162  * (16 bits: 10-bit signed magnitude, 6-bit fraction).
163  */
164 static s32 dts_ten_dot_six_to_millidegree(u16 val)
165 {
166 	return sign_extend32(val, 15) * MILLIDEGREE_PER_DEGREE / 64;
167 }
168 
169 /*
170  * For older processors, thermal margin reading is returned in S8.8 fixed
171  * point format (16 bits: 8-bit signed magnitude, 8-bit fraction).
172  */
173 static s32 dts_eight_dot_eight_to_millidegree(u16 val)
174 {
175 	return sign_extend32(val, 15) * MILLIDEGREE_PER_DEGREE / 256;
176 }
177 
178 static int get_die_temp(struct peci_cputemp *priv, long *val)
179 {
180 	int ret = 0;
181 	long tjmax;
182 	u16 temp;
183 
184 	mutex_lock(&priv->temp.die.state.lock);
185 	if (!peci_sensor_need_update(&priv->temp.die.state))
186 		goto skip_update;
187 
188 	ret = peci_temp_read(priv->peci_dev, &temp);
189 	if (ret)
190 		goto err_unlock;
191 
192 	if (!dts_valid(temp)) {
193 		ret = -EIO;
194 		goto err_unlock;
195 	}
196 
197 	ret = get_temp_target(priv, tjmax_type, &tjmax);
198 	if (ret)
199 		goto err_unlock;
200 
201 	priv->temp.die.value = (s32)tjmax + dts_ten_dot_six_to_millidegree(temp);
202 
203 	peci_sensor_mark_updated(&priv->temp.die.state);
204 
205 skip_update:
206 	*val = priv->temp.die.value;
207 err_unlock:
208 	mutex_unlock(&priv->temp.die.state.lock);
209 	return ret;
210 }
211 
212 static int get_dts(struct peci_cputemp *priv, long *val)
213 {
214 	int ret = 0;
215 	u16 thermal_margin;
216 	long tcontrol;
217 	u32 pcs;
218 
219 	mutex_lock(&priv->temp.dts.state.lock);
220 	if (!peci_sensor_need_update(&priv->temp.dts.state))
221 		goto skip_update;
222 
223 	ret = peci_pcs_read(priv->peci_dev, PECI_PCS_THERMAL_MARGIN, 0, &pcs);
224 	if (ret)
225 		goto err_unlock;
226 
227 	thermal_margin = FIELD_GET(DTS_MARGIN_MASK, pcs);
228 	if (!dts_valid(thermal_margin)) {
229 		ret = -EIO;
230 		goto err_unlock;
231 	}
232 
233 	ret = get_temp_target(priv, tcontrol_type, &tcontrol);
234 	if (ret)
235 		goto err_unlock;
236 
237 	/* Note that the tcontrol should be available before calling it */
238 	priv->temp.dts.value =
239 		(s32)tcontrol - priv->gen_info->thermal_margin_to_millidegree(thermal_margin);
240 
241 	peci_sensor_mark_updated(&priv->temp.dts.state);
242 
243 skip_update:
244 	*val = priv->temp.dts.value;
245 err_unlock:
246 	mutex_unlock(&priv->temp.dts.state.lock);
247 	return ret;
248 }
249 
250 static int get_core_temp(struct peci_cputemp *priv, int core_index, long *val)
251 {
252 	int ret = 0;
253 	u16 core_dts_margin;
254 	long tjmax;
255 	u32 pcs;
256 
257 	mutex_lock(&priv->temp.core[core_index].state.lock);
258 	if (!peci_sensor_need_update(&priv->temp.core[core_index].state))
259 		goto skip_update;
260 
261 	ret = peci_pcs_read(priv->peci_dev, PECI_PCS_MODULE_TEMP, core_index, &pcs);
262 	if (ret)
263 		goto err_unlock;
264 
265 	core_dts_margin = FIELD_GET(PCS_MODULE_TEMP_MASK, pcs);
266 	if (!dts_valid(core_dts_margin)) {
267 		ret = -EIO;
268 		goto err_unlock;
269 	}
270 
271 	ret = get_temp_target(priv, tjmax_type, &tjmax);
272 	if (ret)
273 		goto err_unlock;
274 
275 	/* Note that the tjmax should be available before calling it */
276 	priv->temp.core[core_index].value =
277 		(s32)tjmax + dts_ten_dot_six_to_millidegree(core_dts_margin);
278 
279 	peci_sensor_mark_updated(&priv->temp.core[core_index].state);
280 
281 skip_update:
282 	*val = priv->temp.core[core_index].value;
283 err_unlock:
284 	mutex_unlock(&priv->temp.core[core_index].state.lock);
285 	return ret;
286 }
287 
288 static int cputemp_read_string(struct device *dev, enum hwmon_sensor_types type,
289 			       u32 attr, int channel, const char **str)
290 {
291 	struct peci_cputemp *priv = dev_get_drvdata(dev);
292 
293 	if (attr != hwmon_temp_label)
294 		return -EOPNOTSUPP;
295 
296 	*str = channel < channel_core ?
297 		cputemp_label[channel] : priv->coretemp_label[channel - channel_core];
298 
299 	return 0;
300 }
301 
302 static int cputemp_read(struct device *dev, enum hwmon_sensor_types type,
303 			u32 attr, int channel, long *val)
304 {
305 	struct peci_cputemp *priv = dev_get_drvdata(dev);
306 
307 	switch (attr) {
308 	case hwmon_temp_input:
309 		switch (channel) {
310 		case channel_die:
311 			return get_die_temp(priv, val);
312 		case channel_dts:
313 			return get_dts(priv, val);
314 		case channel_tcontrol:
315 			return get_temp_target(priv, tcontrol_type, val);
316 		case channel_tthrottle:
317 			return get_temp_target(priv, tthrottle_type, val);
318 		case channel_tjmax:
319 			return get_temp_target(priv, tjmax_type, val);
320 		default:
321 			return get_core_temp(priv, channel - channel_core, val);
322 		}
323 		break;
324 	case hwmon_temp_max:
325 		return get_temp_target(priv, tcontrol_type, val);
326 	case hwmon_temp_crit:
327 		return get_temp_target(priv, tjmax_type, val);
328 	case hwmon_temp_crit_hyst:
329 		return get_temp_target(priv, crit_hyst_type, val);
330 	default:
331 		return -EOPNOTSUPP;
332 	}
333 
334 	return 0;
335 }
336 
337 static umode_t cputemp_is_visible(const void *data, enum hwmon_sensor_types type,
338 				  u32 attr, int channel)
339 {
340 	const struct peci_cputemp *priv = data;
341 
342 	if (channel > CPUTEMP_CHANNEL_NUMS)
343 		return 0;
344 
345 	if (channel < channel_core)
346 		return 0444;
347 
348 	if (test_bit(channel - channel_core, priv->core_mask))
349 		return 0444;
350 
351 	return 0;
352 }
353 
354 static int init_core_mask(struct peci_cputemp *priv)
355 {
356 	struct peci_device *peci_dev = priv->peci_dev;
357 	struct resolved_cores_reg *reg = priv->gen_info->reg;
358 	u64 core_mask;
359 	u32 data;
360 	int ret;
361 
362 	/* Get the RESOLVED_CORES register value */
363 	switch (peci_dev->info.model) {
364 	case INTEL_FAM6_ICELAKE_X:
365 	case INTEL_FAM6_ICELAKE_D:
366 		ret = peci_ep_pci_local_read(peci_dev, 0, reg->bus, reg->dev,
367 					     reg->func, reg->offset + 4, &data);
368 		if (ret)
369 			return ret;
370 
371 		core_mask = (u64)data << 32;
372 
373 		ret = peci_ep_pci_local_read(peci_dev, 0, reg->bus, reg->dev,
374 					     reg->func, reg->offset, &data);
375 		if (ret)
376 			return ret;
377 
378 		core_mask |= data;
379 
380 		break;
381 	default:
382 		ret = peci_pci_local_read(peci_dev, reg->bus, reg->dev,
383 					  reg->func, reg->offset, &data);
384 		if (ret)
385 			return ret;
386 
387 		core_mask = data;
388 
389 		break;
390 	}
391 
392 	if (!core_mask)
393 		return -EIO;
394 
395 	bitmap_from_u64(priv->core_mask, core_mask);
396 
397 	return 0;
398 }
399 
400 static int create_temp_label(struct peci_cputemp *priv)
401 {
402 	unsigned long core_max = find_last_bit(priv->core_mask, CORE_NUMS_MAX);
403 	int i;
404 
405 	priv->coretemp_label = devm_kzalloc(priv->dev, (core_max + 1) * sizeof(char *), GFP_KERNEL);
406 	if (!priv->coretemp_label)
407 		return -ENOMEM;
408 
409 	for_each_set_bit(i, priv->core_mask, CORE_NUMS_MAX) {
410 		priv->coretemp_label[i] = devm_kasprintf(priv->dev, GFP_KERNEL, "Core %d", i);
411 		if (!priv->coretemp_label[i])
412 			return -ENOMEM;
413 	}
414 
415 	return 0;
416 }
417 
418 static void check_resolved_cores(struct peci_cputemp *priv)
419 {
420 	/*
421 	 * Failure to resolve cores is non-critical, we're still able to
422 	 * provide other sensor data.
423 	 */
424 
425 	if (init_core_mask(priv))
426 		return;
427 
428 	if (create_temp_label(priv))
429 		bitmap_zero(priv->core_mask, CORE_NUMS_MAX);
430 }
431 
432 static void sensor_init(struct peci_cputemp *priv)
433 {
434 	int i;
435 
436 	mutex_init(&priv->temp.target.state.lock);
437 	mutex_init(&priv->temp.die.state.lock);
438 	mutex_init(&priv->temp.dts.state.lock);
439 
440 	for_each_set_bit(i, priv->core_mask, CORE_NUMS_MAX)
441 		mutex_init(&priv->temp.core[i].state.lock);
442 }
443 
444 static const struct hwmon_ops peci_cputemp_ops = {
445 	.is_visible = cputemp_is_visible,
446 	.read_string = cputemp_read_string,
447 	.read = cputemp_read,
448 };
449 
450 static const struct hwmon_channel_info *peci_cputemp_info[] = {
451 	HWMON_CHANNEL_INFO(temp,
452 			   /* Die temperature */
453 			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
454 			   HWMON_T_CRIT | HWMON_T_CRIT_HYST,
455 			   /* DTS margin */
456 			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
457 			   HWMON_T_CRIT | HWMON_T_CRIT_HYST,
458 			   /* Tcontrol temperature */
459 			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_CRIT,
460 			   /* Tthrottle temperature */
461 			   HWMON_T_LABEL | HWMON_T_INPUT,
462 			   /* Tjmax temperature */
463 			   HWMON_T_LABEL | HWMON_T_INPUT,
464 			   /* Core temperature - for all core channels */
465 			   [channel_core ... CPUTEMP_CHANNEL_NUMS - 1] =
466 						HWMON_T_LABEL | HWMON_T_INPUT),
467 	NULL
468 };
469 
470 static const struct hwmon_chip_info peci_cputemp_chip_info = {
471 	.ops = &peci_cputemp_ops,
472 	.info = peci_cputemp_info,
473 };
474 
475 static int peci_cputemp_probe(struct auxiliary_device *adev,
476 			      const struct auxiliary_device_id *id)
477 {
478 	struct device *dev = &adev->dev;
479 	struct peci_device *peci_dev = to_peci_device(dev->parent);
480 	struct peci_cputemp *priv;
481 	struct device *hwmon_dev;
482 
483 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
484 	if (!priv)
485 		return -ENOMEM;
486 
487 	priv->name = devm_kasprintf(dev, GFP_KERNEL, "peci_cputemp.cpu%d",
488 				    peci_dev->info.socket_id);
489 	if (!priv->name)
490 		return -ENOMEM;
491 
492 	priv->dev = dev;
493 	priv->peci_dev = peci_dev;
494 	priv->gen_info = (const struct cpu_info *)id->driver_data;
495 
496 	/*
497 	 * This is just a sanity check. Since we're using commands that are
498 	 * guaranteed to be supported on a given platform, we should never see
499 	 * revision lower than expected.
500 	 */
501 	if (peci_dev->info.peci_revision < priv->gen_info->min_peci_revision)
502 		dev_warn(priv->dev,
503 			 "Unexpected PECI revision %#x, some features may be unavailable\n",
504 			 peci_dev->info.peci_revision);
505 
506 	check_resolved_cores(priv);
507 
508 	sensor_init(priv);
509 
510 	hwmon_dev = devm_hwmon_device_register_with_info(priv->dev, priv->name,
511 							 priv, &peci_cputemp_chip_info, NULL);
512 
513 	return PTR_ERR_OR_ZERO(hwmon_dev);
514 }
515 
516 /*
517  * RESOLVED_CORES PCI configuration register may have different location on
518  * different platforms.
519  */
520 static struct resolved_cores_reg resolved_cores_reg_hsx = {
521 	.bus = 1,
522 	.dev = 30,
523 	.func = 3,
524 	.offset = 0xb4,
525 };
526 
527 static struct resolved_cores_reg resolved_cores_reg_icx = {
528 	.bus = 14,
529 	.dev = 30,
530 	.func = 3,
531 	.offset = 0xd0,
532 };
533 
534 static const struct cpu_info cpu_hsx = {
535 	.reg		= &resolved_cores_reg_hsx,
536 	.min_peci_revision = 0x33,
537 	.thermal_margin_to_millidegree = &dts_eight_dot_eight_to_millidegree,
538 };
539 
540 static const struct cpu_info cpu_skx = {
541 	.reg		= &resolved_cores_reg_hsx,
542 	.min_peci_revision = 0x33,
543 	.thermal_margin_to_millidegree = &dts_ten_dot_six_to_millidegree,
544 };
545 
546 static const struct cpu_info cpu_icx = {
547 	.reg		= &resolved_cores_reg_icx,
548 	.min_peci_revision = 0x40,
549 	.thermal_margin_to_millidegree = &dts_ten_dot_six_to_millidegree,
550 };
551 
552 static const struct auxiliary_device_id peci_cputemp_ids[] = {
553 	{
554 		.name = "peci_cpu.cputemp.hsx",
555 		.driver_data = (kernel_ulong_t)&cpu_hsx,
556 	},
557 	{
558 		.name = "peci_cpu.cputemp.bdx",
559 		.driver_data = (kernel_ulong_t)&cpu_hsx,
560 	},
561 	{
562 		.name = "peci_cpu.cputemp.bdxd",
563 		.driver_data = (kernel_ulong_t)&cpu_hsx,
564 	},
565 	{
566 		.name = "peci_cpu.cputemp.skx",
567 		.driver_data = (kernel_ulong_t)&cpu_skx,
568 	},
569 	{
570 		.name = "peci_cpu.cputemp.icx",
571 		.driver_data = (kernel_ulong_t)&cpu_icx,
572 	},
573 	{
574 		.name = "peci_cpu.cputemp.icxd",
575 		.driver_data = (kernel_ulong_t)&cpu_icx,
576 	},
577 	{ }
578 };
579 MODULE_DEVICE_TABLE(auxiliary, peci_cputemp_ids);
580 
581 static struct auxiliary_driver peci_cputemp_driver = {
582 	.probe		= peci_cputemp_probe,
583 	.id_table	= peci_cputemp_ids,
584 };
585 
586 module_auxiliary_driver(peci_cputemp_driver);
587 
588 MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>");
589 MODULE_AUTHOR("Iwona Winiarska <iwona.winiarska@intel.com>");
590 MODULE_DESCRIPTION("PECI cputemp driver");
591 MODULE_LICENSE("GPL");
592 MODULE_IMPORT_NS(PECI_CPU);
593