xref: /openbmc/linux/drivers/hwmon/ibmpowernv.c (revision a17922de)
1 /*
2  * IBM PowerNV platform sensors for temperature/fan/voltage/power
3  * Copyright (C) 2014 IBM
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program.
17  */
18 
19 #define DRVNAME		"ibmpowernv"
20 #define pr_fmt(fmt)	DRVNAME ": " fmt
21 
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/kernel.h>
25 #include <linux/hwmon.h>
26 #include <linux/hwmon-sysfs.h>
27 #include <linux/of.h>
28 #include <linux/slab.h>
29 
30 #include <linux/platform_device.h>
31 #include <asm/opal.h>
32 #include <linux/err.h>
33 #include <asm/cputhreads.h>
34 #include <asm/smp.h>
35 
36 #define MAX_ATTR_LEN	32
37 #define MAX_LABEL_LEN	64
38 
39 /* Sensor suffix name from DT */
40 #define DT_FAULT_ATTR_SUFFIX		"faulted"
41 #define DT_DATA_ATTR_SUFFIX		"data"
42 #define DT_THRESHOLD_ATTR_SUFFIX	"thrs"
43 
44 /*
45  * Enumerates all the types of sensors in the POWERNV platform and does index
46  * into 'struct sensor_group'
47  */
48 enum sensors {
49 	FAN,
50 	TEMP,
51 	POWER_SUPPLY,
52 	POWER_INPUT,
53 	CURRENT,
54 	ENERGY,
55 	MAX_SENSOR_TYPE,
56 };
57 
58 #define INVALID_INDEX (-1U)
59 
60 /*
61  * 'compatible' string properties for sensor types as defined in old
62  * PowerNV firmware (skiboot). These are ordered as 'enum sensors'.
63  */
64 static const char * const legacy_compatibles[] = {
65 	"ibm,opal-sensor-cooling-fan",
66 	"ibm,opal-sensor-amb-temp",
67 	"ibm,opal-sensor-power-supply",
68 	"ibm,opal-sensor-power"
69 };
70 
71 static struct sensor_group {
72 	const char *name; /* matches property 'sensor-type' */
73 	struct attribute_group group;
74 	u32 attr_count;
75 	u32 hwmon_index;
76 } sensor_groups[] = {
77 	{ "fan"   },
78 	{ "temp"  },
79 	{ "in"    },
80 	{ "power" },
81 	{ "curr"  },
82 	{ "energy" },
83 };
84 
85 struct sensor_data {
86 	u32 id; /* An opaque id of the firmware for each sensor */
87 	u32 hwmon_index;
88 	u32 opal_index;
89 	enum sensors type;
90 	char label[MAX_LABEL_LEN];
91 	char name[MAX_ATTR_LEN];
92 	struct device_attribute dev_attr;
93 };
94 
95 struct platform_data {
96 	const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1];
97 	u32 sensors_count; /* Total count of sensors from each group */
98 };
99 
100 static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr,
101 			   char *buf)
102 {
103 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
104 						 dev_attr);
105 	ssize_t ret;
106 	u64 x;
107 
108 	ret =  opal_get_sensor_data_u64(sdata->id, &x);
109 
110 	if (ret)
111 		return ret;
112 
113 	/* Convert temperature to milli-degrees */
114 	if (sdata->type == TEMP)
115 		x *= 1000;
116 	/* Convert power to micro-watts */
117 	else if (sdata->type == POWER_INPUT)
118 		x *= 1000000;
119 
120 	return sprintf(buf, "%llu\n", x);
121 }
122 
123 static ssize_t show_label(struct device *dev, struct device_attribute *devattr,
124 			  char *buf)
125 {
126 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
127 						 dev_attr);
128 
129 	return sprintf(buf, "%s\n", sdata->label);
130 }
131 
132 static int __init get_logical_cpu(int hwcpu)
133 {
134 	int cpu;
135 
136 	for_each_possible_cpu(cpu)
137 		if (get_hard_smp_processor_id(cpu) == hwcpu)
138 			return cpu;
139 
140 	return -ENOENT;
141 }
142 
143 static void __init make_sensor_label(struct device_node *np,
144 				     struct sensor_data *sdata,
145 				     const char *label)
146 {
147 	u32 id;
148 	size_t n;
149 
150 	n = snprintf(sdata->label, sizeof(sdata->label), "%s", label);
151 
152 	/*
153 	 * Core temp pretty print
154 	 */
155 	if (!of_property_read_u32(np, "ibm,pir", &id)) {
156 		int cpuid = get_logical_cpu(id);
157 
158 		if (cpuid >= 0)
159 			/*
160 			 * The digital thermal sensors are associated
161 			 * with a core.
162 			 */
163 			n += snprintf(sdata->label + n,
164 				      sizeof(sdata->label) - n, " %d",
165 				      cpuid);
166 		else
167 			n += snprintf(sdata->label + n,
168 				      sizeof(sdata->label) - n, " phy%d", id);
169 	}
170 
171 	/*
172 	 * Membuffer pretty print
173 	 */
174 	if (!of_property_read_u32(np, "ibm,chip-id", &id))
175 		n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
176 			      " %d", id & 0xffff);
177 }
178 
179 static int get_sensor_index_attr(const char *name, u32 *index, char *attr)
180 {
181 	char *hash_pos = strchr(name, '#');
182 	char buf[8] = { 0 };
183 	char *dash_pos;
184 	u32 copy_len;
185 	int err;
186 
187 	if (!hash_pos)
188 		return -EINVAL;
189 
190 	dash_pos = strchr(hash_pos, '-');
191 	if (!dash_pos)
192 		return -EINVAL;
193 
194 	copy_len = dash_pos - hash_pos - 1;
195 	if (copy_len >= sizeof(buf))
196 		return -EINVAL;
197 
198 	strncpy(buf, hash_pos + 1, copy_len);
199 
200 	err = kstrtou32(buf, 10, index);
201 	if (err)
202 		return err;
203 
204 	strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
205 
206 	return 0;
207 }
208 
209 static const char *convert_opal_attr_name(enum sensors type,
210 					  const char *opal_attr)
211 {
212 	const char *attr_name = NULL;
213 
214 	if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
215 		attr_name = "fault";
216 	} else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
217 		attr_name = "input";
218 	} else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
219 		if (type == TEMP)
220 			attr_name = "max";
221 		else if (type == FAN)
222 			attr_name = "min";
223 	}
224 
225 	return attr_name;
226 }
227 
228 /*
229  * This function translates the DT node name into the 'hwmon' attribute name.
230  * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
231  * which need to be mapped as fan2_input, temp1_max respectively before
232  * populating them inside hwmon device class.
233  */
234 static const char *parse_opal_node_name(const char *node_name,
235 					enum sensors type, u32 *index)
236 {
237 	char attr_suffix[MAX_ATTR_LEN];
238 	const char *attr_name;
239 	int err;
240 
241 	err = get_sensor_index_attr(node_name, index, attr_suffix);
242 	if (err)
243 		return ERR_PTR(err);
244 
245 	attr_name = convert_opal_attr_name(type, attr_suffix);
246 	if (!attr_name)
247 		return ERR_PTR(-ENOENT);
248 
249 	return attr_name;
250 }
251 
252 static int get_sensor_type(struct device_node *np)
253 {
254 	enum sensors type;
255 	const char *str;
256 
257 	for (type = 0; type < ARRAY_SIZE(legacy_compatibles); type++) {
258 		if (of_device_is_compatible(np, legacy_compatibles[type]))
259 			return type;
260 	}
261 
262 	/*
263 	 * Let's check if we have a newer device tree
264 	 */
265 	if (!of_device_is_compatible(np, "ibm,opal-sensor"))
266 		return MAX_SENSOR_TYPE;
267 
268 	if (of_property_read_string(np, "sensor-type", &str))
269 		return MAX_SENSOR_TYPE;
270 
271 	for (type = 0; type < MAX_SENSOR_TYPE; type++)
272 		if (!strcmp(str, sensor_groups[type].name))
273 			return type;
274 
275 	return MAX_SENSOR_TYPE;
276 }
277 
278 static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
279 				  struct sensor_data *sdata_table, int count)
280 {
281 	int i;
282 
283 	/*
284 	 * We don't use the OPAL index on newer device trees
285 	 */
286 	if (sdata->opal_index != INVALID_INDEX) {
287 		for (i = 0; i < count; i++)
288 			if (sdata_table[i].opal_index == sdata->opal_index &&
289 			    sdata_table[i].type == sdata->type)
290 				return sdata_table[i].hwmon_index;
291 	}
292 	return ++sensor_groups[sdata->type].hwmon_index;
293 }
294 
295 static int populate_attr_groups(struct platform_device *pdev)
296 {
297 	struct platform_data *pdata = platform_get_drvdata(pdev);
298 	const struct attribute_group **pgroups = pdata->attr_groups;
299 	struct device_node *opal, *np;
300 	enum sensors type;
301 
302 	opal = of_find_node_by_path("/ibm,opal/sensors");
303 	for_each_child_of_node(opal, np) {
304 		const char *label;
305 
306 		if (np->name == NULL)
307 			continue;
308 
309 		type = get_sensor_type(np);
310 		if (type == MAX_SENSOR_TYPE)
311 			continue;
312 
313 		sensor_groups[type].attr_count++;
314 
315 		/*
316 		 * add attributes for labels, min and max
317 		 */
318 		if (!of_property_read_string(np, "label", &label))
319 			sensor_groups[type].attr_count++;
320 		if (of_find_property(np, "sensor-data-min", NULL))
321 			sensor_groups[type].attr_count++;
322 		if (of_find_property(np, "sensor-data-max", NULL))
323 			sensor_groups[type].attr_count++;
324 	}
325 
326 	of_node_put(opal);
327 
328 	for (type = 0; type < MAX_SENSOR_TYPE; type++) {
329 		sensor_groups[type].group.attrs = devm_kcalloc(&pdev->dev,
330 					sensor_groups[type].attr_count + 1,
331 					sizeof(struct attribute *),
332 					GFP_KERNEL);
333 		if (!sensor_groups[type].group.attrs)
334 			return -ENOMEM;
335 
336 		pgroups[type] = &sensor_groups[type].group;
337 		pdata->sensors_count += sensor_groups[type].attr_count;
338 		sensor_groups[type].attr_count = 0;
339 	}
340 
341 	return 0;
342 }
343 
344 static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
345 			      ssize_t (*show)(struct device *dev,
346 					      struct device_attribute *attr,
347 					      char *buf))
348 {
349 	snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
350 		 sensor_groups[sdata->type].name, sdata->hwmon_index,
351 		 attr_name);
352 
353 	sysfs_attr_init(&sdata->dev_attr.attr);
354 	sdata->dev_attr.attr.name = sdata->name;
355 	sdata->dev_attr.attr.mode = S_IRUGO;
356 	sdata->dev_attr.show = show;
357 }
358 
359 static void populate_sensor(struct sensor_data *sdata, int od, int hd, int sid,
360 			    const char *attr_name, enum sensors type,
361 			    const struct attribute_group *pgroup,
362 			    ssize_t (*show)(struct device *dev,
363 					    struct device_attribute *attr,
364 					    char *buf))
365 {
366 	sdata->id = sid;
367 	sdata->type = type;
368 	sdata->opal_index = od;
369 	sdata->hwmon_index = hd;
370 	create_hwmon_attr(sdata, attr_name, show);
371 	pgroup->attrs[sensor_groups[type].attr_count++] = &sdata->dev_attr.attr;
372 }
373 
374 static char *get_max_attr(enum sensors type)
375 {
376 	switch (type) {
377 	case POWER_INPUT:
378 		return "input_highest";
379 	default:
380 		return "highest";
381 	}
382 }
383 
384 static char *get_min_attr(enum sensors type)
385 {
386 	switch (type) {
387 	case POWER_INPUT:
388 		return "input_lowest";
389 	default:
390 		return "lowest";
391 	}
392 }
393 
394 /*
395  * Iterate through the device tree for each child of 'sensors' node, create
396  * a sysfs attribute file, the file is named by translating the DT node name
397  * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
398  * etc..
399  */
400 static int create_device_attrs(struct platform_device *pdev)
401 {
402 	struct platform_data *pdata = platform_get_drvdata(pdev);
403 	const struct attribute_group **pgroups = pdata->attr_groups;
404 	struct device_node *opal, *np;
405 	struct sensor_data *sdata;
406 	u32 sensor_id;
407 	enum sensors type;
408 	u32 count = 0;
409 	int err = 0;
410 
411 	opal = of_find_node_by_path("/ibm,opal/sensors");
412 	sdata = devm_kcalloc(&pdev->dev,
413 			     pdata->sensors_count, sizeof(*sdata),
414 			     GFP_KERNEL);
415 	if (!sdata) {
416 		err = -ENOMEM;
417 		goto exit_put_node;
418 	}
419 
420 	for_each_child_of_node(opal, np) {
421 		const char *attr_name;
422 		u32 opal_index;
423 		const char *label;
424 
425 		if (np->name == NULL)
426 			continue;
427 
428 		type = get_sensor_type(np);
429 		if (type == MAX_SENSOR_TYPE)
430 			continue;
431 
432 		/*
433 		 * Newer device trees use a "sensor-data" property
434 		 * name for input.
435 		 */
436 		if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
437 		    of_property_read_u32(np, "sensor-data", &sensor_id)) {
438 			dev_info(&pdev->dev,
439 				 "'sensor-id' missing in the node '%s'\n",
440 				 np->name);
441 			continue;
442 		}
443 
444 		sdata[count].id = sensor_id;
445 		sdata[count].type = type;
446 
447 		/*
448 		 * If we can not parse the node name, it means we are
449 		 * running on a newer device tree. We can just forget
450 		 * about the OPAL index and use a defaut value for the
451 		 * hwmon attribute name
452 		 */
453 		attr_name = parse_opal_node_name(np->name, type, &opal_index);
454 		if (IS_ERR(attr_name)) {
455 			attr_name = "input";
456 			opal_index = INVALID_INDEX;
457 		}
458 
459 		sdata[count].opal_index = opal_index;
460 		sdata[count].hwmon_index =
461 			get_sensor_hwmon_index(&sdata[count], sdata, count);
462 
463 		create_hwmon_attr(&sdata[count], attr_name, show_sensor);
464 
465 		pgroups[type]->attrs[sensor_groups[type].attr_count++] =
466 				&sdata[count++].dev_attr.attr;
467 
468 		if (!of_property_read_string(np, "label", &label)) {
469 			/*
470 			 * For the label attribute, we can reuse the
471 			 * "properties" of the previous "input"
472 			 * attribute. They are related to the same
473 			 * sensor.
474 			 */
475 
476 			make_sensor_label(np, &sdata[count], label);
477 			populate_sensor(&sdata[count], opal_index,
478 					sdata[count - 1].hwmon_index,
479 					sensor_id, "label", type, pgroups[type],
480 					show_label);
481 			count++;
482 		}
483 
484 		if (!of_property_read_u32(np, "sensor-data-max", &sensor_id)) {
485 			attr_name = get_max_attr(type);
486 			populate_sensor(&sdata[count], opal_index,
487 					sdata[count - 1].hwmon_index,
488 					sensor_id, attr_name, type,
489 					pgroups[type], show_sensor);
490 			count++;
491 		}
492 
493 		if (!of_property_read_u32(np, "sensor-data-min", &sensor_id)) {
494 			attr_name = get_min_attr(type);
495 			populate_sensor(&sdata[count], opal_index,
496 					sdata[count - 1].hwmon_index,
497 					sensor_id, attr_name, type,
498 					pgroups[type], show_sensor);
499 			count++;
500 		}
501 	}
502 
503 exit_put_node:
504 	of_node_put(opal);
505 	return err;
506 }
507 
508 static int ibmpowernv_probe(struct platform_device *pdev)
509 {
510 	struct platform_data *pdata;
511 	struct device *hwmon_dev;
512 	int err;
513 
514 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
515 	if (!pdata)
516 		return -ENOMEM;
517 
518 	platform_set_drvdata(pdev, pdata);
519 	pdata->sensors_count = 0;
520 	err = populate_attr_groups(pdev);
521 	if (err)
522 		return err;
523 
524 	/* Create sysfs attribute data for each sensor found in the DT */
525 	err = create_device_attrs(pdev);
526 	if (err)
527 		return err;
528 
529 	/* Finally, register with hwmon */
530 	hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
531 							   pdata,
532 							   pdata->attr_groups);
533 
534 	return PTR_ERR_OR_ZERO(hwmon_dev);
535 }
536 
537 static const struct platform_device_id opal_sensor_driver_ids[] = {
538 	{
539 		.name = "opal-sensor",
540 	},
541 	{ }
542 };
543 MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
544 
545 static const struct of_device_id opal_sensor_match[] = {
546 	{ .compatible	= "ibm,opal-sensor" },
547 	{ },
548 };
549 MODULE_DEVICE_TABLE(of, opal_sensor_match);
550 
551 static struct platform_driver ibmpowernv_driver = {
552 	.probe		= ibmpowernv_probe,
553 	.id_table	= opal_sensor_driver_ids,
554 	.driver		= {
555 		.name	= DRVNAME,
556 		.of_match_table	= opal_sensor_match,
557 	},
558 };
559 
560 module_platform_driver(ibmpowernv_driver);
561 
562 MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
563 MODULE_DESCRIPTION("IBM POWERNV platform sensors");
564 MODULE_LICENSE("GPL");
565