xref: /openbmc/linux/drivers/hwmon/peci/cputemp.c (revision e9b7b8b3)
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 	case INTEL_FAM6_SAPPHIRERAPIDS_X:
367 		ret = peci_ep_pci_local_read(peci_dev, 0, reg->bus, reg->dev,
368 					     reg->func, reg->offset + 4, &data);
369 		if (ret)
370 			return ret;
371 
372 		core_mask = (u64)data << 32;
373 
374 		ret = peci_ep_pci_local_read(peci_dev, 0, reg->bus, reg->dev,
375 					     reg->func, reg->offset, &data);
376 		if (ret)
377 			return ret;
378 
379 		core_mask |= data;
380 
381 		break;
382 	default:
383 		ret = peci_pci_local_read(peci_dev, reg->bus, reg->dev,
384 					  reg->func, reg->offset, &data);
385 		if (ret)
386 			return ret;
387 
388 		core_mask = data;
389 
390 		break;
391 	}
392 
393 	if (!core_mask)
394 		return -EIO;
395 
396 	bitmap_from_u64(priv->core_mask, core_mask);
397 
398 	return 0;
399 }
400 
401 static int create_temp_label(struct peci_cputemp *priv)
402 {
403 	unsigned long core_max = find_last_bit(priv->core_mask, CORE_NUMS_MAX);
404 	int i;
405 
406 	priv->coretemp_label = devm_kzalloc(priv->dev, (core_max + 1) * sizeof(char *), GFP_KERNEL);
407 	if (!priv->coretemp_label)
408 		return -ENOMEM;
409 
410 	for_each_set_bit(i, priv->core_mask, CORE_NUMS_MAX) {
411 		priv->coretemp_label[i] = devm_kasprintf(priv->dev, GFP_KERNEL, "Core %d", i);
412 		if (!priv->coretemp_label[i])
413 			return -ENOMEM;
414 	}
415 
416 	return 0;
417 }
418 
419 static void check_resolved_cores(struct peci_cputemp *priv)
420 {
421 	/*
422 	 * Failure to resolve cores is non-critical, we're still able to
423 	 * provide other sensor data.
424 	 */
425 
426 	if (init_core_mask(priv))
427 		return;
428 
429 	if (create_temp_label(priv))
430 		bitmap_zero(priv->core_mask, CORE_NUMS_MAX);
431 }
432 
433 static void sensor_init(struct peci_cputemp *priv)
434 {
435 	int i;
436 
437 	mutex_init(&priv->temp.target.state.lock);
438 	mutex_init(&priv->temp.die.state.lock);
439 	mutex_init(&priv->temp.dts.state.lock);
440 
441 	for_each_set_bit(i, priv->core_mask, CORE_NUMS_MAX)
442 		mutex_init(&priv->temp.core[i].state.lock);
443 }
444 
445 static const struct hwmon_ops peci_cputemp_ops = {
446 	.is_visible = cputemp_is_visible,
447 	.read_string = cputemp_read_string,
448 	.read = cputemp_read,
449 };
450 
451 static const struct hwmon_channel_info * const peci_cputemp_info[] = {
452 	HWMON_CHANNEL_INFO(temp,
453 			   /* Die temperature */
454 			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
455 			   HWMON_T_CRIT | HWMON_T_CRIT_HYST,
456 			   /* DTS margin */
457 			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
458 			   HWMON_T_CRIT | HWMON_T_CRIT_HYST,
459 			   /* Tcontrol temperature */
460 			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_CRIT,
461 			   /* Tthrottle temperature */
462 			   HWMON_T_LABEL | HWMON_T_INPUT,
463 			   /* Tjmax temperature */
464 			   HWMON_T_LABEL | HWMON_T_INPUT,
465 			   /* Core temperature - for all core channels */
466 			   [channel_core ... CPUTEMP_CHANNEL_NUMS - 1] =
467 						HWMON_T_LABEL | HWMON_T_INPUT),
468 	NULL
469 };
470 
471 static const struct hwmon_chip_info peci_cputemp_chip_info = {
472 	.ops = &peci_cputemp_ops,
473 	.info = peci_cputemp_info,
474 };
475 
476 static int peci_cputemp_probe(struct auxiliary_device *adev,
477 			      const struct auxiliary_device_id *id)
478 {
479 	struct device *dev = &adev->dev;
480 	struct peci_device *peci_dev = to_peci_device(dev->parent);
481 	struct peci_cputemp *priv;
482 	struct device *hwmon_dev;
483 
484 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
485 	if (!priv)
486 		return -ENOMEM;
487 
488 	priv->name = devm_kasprintf(dev, GFP_KERNEL, "peci_cputemp.cpu%d",
489 				    peci_dev->info.socket_id);
490 	if (!priv->name)
491 		return -ENOMEM;
492 
493 	priv->dev = dev;
494 	priv->peci_dev = peci_dev;
495 	priv->gen_info = (const struct cpu_info *)id->driver_data;
496 
497 	/*
498 	 * This is just a sanity check. Since we're using commands that are
499 	 * guaranteed to be supported on a given platform, we should never see
500 	 * revision lower than expected.
501 	 */
502 	if (peci_dev->info.peci_revision < priv->gen_info->min_peci_revision)
503 		dev_warn(priv->dev,
504 			 "Unexpected PECI revision %#x, some features may be unavailable\n",
505 			 peci_dev->info.peci_revision);
506 
507 	check_resolved_cores(priv);
508 
509 	sensor_init(priv);
510 
511 	hwmon_dev = devm_hwmon_device_register_with_info(priv->dev, priv->name,
512 							 priv, &peci_cputemp_chip_info, NULL);
513 
514 	return PTR_ERR_OR_ZERO(hwmon_dev);
515 }
516 
517 /*
518  * RESOLVED_CORES PCI configuration register may have different location on
519  * different platforms.
520  */
521 static struct resolved_cores_reg resolved_cores_reg_hsx = {
522 	.bus = 1,
523 	.dev = 30,
524 	.func = 3,
525 	.offset = 0xb4,
526 };
527 
528 static struct resolved_cores_reg resolved_cores_reg_icx = {
529 	.bus = 14,
530 	.dev = 30,
531 	.func = 3,
532 	.offset = 0xd0,
533 };
534 
535 static struct resolved_cores_reg resolved_cores_reg_spr = {
536 	.bus = 31,
537 	.dev = 30,
538 	.func = 6,
539 	.offset = 0x80,
540 };
541 
542 static const struct cpu_info cpu_hsx = {
543 	.reg		= &resolved_cores_reg_hsx,
544 	.min_peci_revision = 0x33,
545 	.thermal_margin_to_millidegree = &dts_eight_dot_eight_to_millidegree,
546 };
547 
548 static const struct cpu_info cpu_skx = {
549 	.reg		= &resolved_cores_reg_hsx,
550 	.min_peci_revision = 0x33,
551 	.thermal_margin_to_millidegree = &dts_ten_dot_six_to_millidegree,
552 };
553 
554 static const struct cpu_info cpu_icx = {
555 	.reg		= &resolved_cores_reg_icx,
556 	.min_peci_revision = 0x40,
557 	.thermal_margin_to_millidegree = &dts_ten_dot_six_to_millidegree,
558 };
559 
560 static const struct cpu_info cpu_spr = {
561 	.reg		= &resolved_cores_reg_spr,
562 	.min_peci_revision = 0x40,
563 	.thermal_margin_to_millidegree = &dts_ten_dot_six_to_millidegree,
564 };
565 
566 static const struct auxiliary_device_id peci_cputemp_ids[] = {
567 	{
568 		.name = "peci_cpu.cputemp.hsx",
569 		.driver_data = (kernel_ulong_t)&cpu_hsx,
570 	},
571 	{
572 		.name = "peci_cpu.cputemp.bdx",
573 		.driver_data = (kernel_ulong_t)&cpu_hsx,
574 	},
575 	{
576 		.name = "peci_cpu.cputemp.bdxd",
577 		.driver_data = (kernel_ulong_t)&cpu_hsx,
578 	},
579 	{
580 		.name = "peci_cpu.cputemp.skx",
581 		.driver_data = (kernel_ulong_t)&cpu_skx,
582 	},
583 	{
584 		.name = "peci_cpu.cputemp.icx",
585 		.driver_data = (kernel_ulong_t)&cpu_icx,
586 	},
587 	{
588 		.name = "peci_cpu.cputemp.icxd",
589 		.driver_data = (kernel_ulong_t)&cpu_icx,
590 	},
591 	{
592 		.name = "peci_cpu.cputemp.spr",
593 		.driver_data = (kernel_ulong_t)&cpu_spr,
594 	},
595 	{ }
596 };
597 MODULE_DEVICE_TABLE(auxiliary, peci_cputemp_ids);
598 
599 static struct auxiliary_driver peci_cputemp_driver = {
600 	.probe		= peci_cputemp_probe,
601 	.id_table	= peci_cputemp_ids,
602 };
603 
604 module_auxiliary_driver(peci_cputemp_driver);
605 
606 MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>");
607 MODULE_AUTHOR("Iwona Winiarska <iwona.winiarska@intel.com>");
608 MODULE_DESCRIPTION("PECI cputemp driver");
609 MODULE_LICENSE("GPL");
610 MODULE_IMPORT_NS(PECI_CPU);
611