1 // SPDX-License-Identifier: GPL-2.0-only
2 /****************************************************************************
3  * Driver for Solarflare network controllers and boards
4  * Copyright 2011-2013 Solarflare Communications Inc.
5  */
6 
7 #include <linux/bitops.h>
8 #include <linux/slab.h>
9 #include <linux/hwmon.h>
10 #include <linux/stat.h>
11 
12 #include "net_driver.h"
13 #include "mcdi.h"
14 #include "mcdi_pcol.h"
15 #include "nic.h"
16 
17 enum efx_hwmon_type {
18 	EFX_HWMON_UNKNOWN,
19 	EFX_HWMON_TEMP,         /* temperature */
20 	EFX_HWMON_COOL,         /* cooling device, probably a heatsink */
21 	EFX_HWMON_IN,		/* voltage */
22 	EFX_HWMON_CURR,		/* current */
23 	EFX_HWMON_POWER,	/* power */
24 	EFX_HWMON_TYPES_COUNT
25 };
26 
27 static const char *const efx_hwmon_unit[EFX_HWMON_TYPES_COUNT] = {
28 	[EFX_HWMON_TEMP]  = " degC",
29 	[EFX_HWMON_COOL]  = " rpm", /* though nonsense for a heatsink */
30 	[EFX_HWMON_IN]    = " mV",
31 	[EFX_HWMON_CURR]  = " mA",
32 	[EFX_HWMON_POWER] = " W",
33 };
34 
35 static const struct {
36 	const char *label;
37 	enum efx_hwmon_type hwmon_type;
38 	int port;
39 } efx_mcdi_sensor_type[] = {
40 #define SENSOR(name, label, hwmon_type, port)				\
41 	[MC_CMD_SENSOR_##name] = { label, EFX_HWMON_ ## hwmon_type, port }
42 	SENSOR(CONTROLLER_TEMP,		"Controller board temp.",   TEMP,  -1),
43 	SENSOR(PHY_COMMON_TEMP,		"PHY temp.",		    TEMP,  -1),
44 	SENSOR(CONTROLLER_COOLING,	"Controller heat sink",	    COOL,  -1),
45 	SENSOR(PHY0_TEMP,		"PHY temp.",		    TEMP,  0),
46 	SENSOR(PHY0_COOLING,		"PHY heat sink",	    COOL,  0),
47 	SENSOR(PHY1_TEMP,		"PHY temp.",		    TEMP,  1),
48 	SENSOR(PHY1_COOLING,		"PHY heat sink",	    COOL,  1),
49 	SENSOR(IN_1V0,			"1.0V supply",		    IN,    -1),
50 	SENSOR(IN_1V2,			"1.2V supply",		    IN,    -1),
51 	SENSOR(IN_1V8,			"1.8V supply",		    IN,    -1),
52 	SENSOR(IN_2V5,			"2.5V supply",		    IN,    -1),
53 	SENSOR(IN_3V3,			"3.3V supply",		    IN,    -1),
54 	SENSOR(IN_12V0,			"12.0V supply",		    IN,    -1),
55 	SENSOR(IN_1V2A,			"1.2V analogue supply",	    IN,    -1),
56 	SENSOR(IN_VREF,			"Ref. voltage",		    IN,    -1),
57 	SENSOR(OUT_VAOE,		"AOE FPGA supply",	    IN,    -1),
58 	SENSOR(AOE_TEMP,		"AOE FPGA temp.",	    TEMP,  -1),
59 	SENSOR(PSU_AOE_TEMP,		"AOE regulator temp.",	    TEMP,  -1),
60 	SENSOR(PSU_TEMP,		"Controller regulator temp.",
61 								    TEMP,  -1),
62 	SENSOR(FAN_0,			"Fan 0",		    COOL,  -1),
63 	SENSOR(FAN_1,			"Fan 1",		    COOL,  -1),
64 	SENSOR(FAN_2,			"Fan 2",		    COOL,  -1),
65 	SENSOR(FAN_3,			"Fan 3",		    COOL,  -1),
66 	SENSOR(FAN_4,			"Fan 4",		    COOL,  -1),
67 	SENSOR(IN_VAOE,			"AOE input supply",	    IN,    -1),
68 	SENSOR(OUT_IAOE,		"AOE output current",	    CURR,  -1),
69 	SENSOR(IN_IAOE,			"AOE input current",	    CURR,  -1),
70 	SENSOR(NIC_POWER,		"Board power use",	    POWER, -1),
71 	SENSOR(IN_0V9,			"0.9V supply",		    IN,    -1),
72 	SENSOR(IN_I0V9,			"0.9V supply current",	    CURR,  -1),
73 	SENSOR(IN_I1V2,			"1.2V supply current",	    CURR,  -1),
74 	SENSOR(IN_0V9_ADC,		"0.9V supply (ext. ADC)",   IN,    -1),
75 	SENSOR(CONTROLLER_2_TEMP,	"Controller board temp. 2", TEMP,  -1),
76 	SENSOR(VREG_INTERNAL_TEMP,	"Regulator die temp.",	    TEMP,  -1),
77 	SENSOR(VREG_0V9_TEMP,		"0.9V regulator temp.",     TEMP,  -1),
78 	SENSOR(VREG_1V2_TEMP,		"1.2V regulator temp.",     TEMP,  -1),
79 	SENSOR(CONTROLLER_VPTAT,
80 			      "Controller PTAT voltage (int. ADC)", IN,    -1),
81 	SENSOR(CONTROLLER_INTERNAL_TEMP,
82 				 "Controller die temp. (int. ADC)", TEMP,  -1),
83 	SENSOR(CONTROLLER_VPTAT_EXTADC,
84 			      "Controller PTAT voltage (ext. ADC)", IN,    -1),
85 	SENSOR(CONTROLLER_INTERNAL_TEMP_EXTADC,
86 				 "Controller die temp. (ext. ADC)", TEMP,  -1),
87 	SENSOR(AMBIENT_TEMP,		"Ambient temp.",	    TEMP,  -1),
88 	SENSOR(AIRFLOW,			"Air flow raw",		    IN,    -1),
89 	SENSOR(VDD08D_VSS08D_CSR,	"0.9V die (int. ADC)",	    IN,    -1),
90 	SENSOR(VDD08D_VSS08D_CSR_EXTADC, "0.9V die (ext. ADC)",	    IN,    -1),
91 	SENSOR(HOTPOINT_TEMP,  "Controller board temp. (hotpoint)", TEMP,  -1),
92 #undef SENSOR
93 };
94 
95 static const char *const sensor_status_names[] = {
96 	[MC_CMD_SENSOR_STATE_OK] = "OK",
97 	[MC_CMD_SENSOR_STATE_WARNING] = "Warning",
98 	[MC_CMD_SENSOR_STATE_FATAL] = "Fatal",
99 	[MC_CMD_SENSOR_STATE_BROKEN] = "Device failure",
100 	[MC_CMD_SENSOR_STATE_NO_READING] = "No reading",
101 };
102 
103 void efx_mcdi_sensor_event(struct efx_nic *efx, efx_qword_t *ev)
104 {
105 	unsigned int type, state, value;
106 	enum efx_hwmon_type hwmon_type = EFX_HWMON_UNKNOWN;
107 	const char *name = NULL, *state_txt, *unit;
108 
109 	type = EFX_QWORD_FIELD(*ev, MCDI_EVENT_SENSOREVT_MONITOR);
110 	state = EFX_QWORD_FIELD(*ev, MCDI_EVENT_SENSOREVT_STATE);
111 	value = EFX_QWORD_FIELD(*ev, MCDI_EVENT_SENSOREVT_VALUE);
112 
113 	/* Deal gracefully with the board having more drivers than we
114 	 * know about, but do not expect new sensor states. */
115 	if (type < ARRAY_SIZE(efx_mcdi_sensor_type)) {
116 		name = efx_mcdi_sensor_type[type].label;
117 		hwmon_type = efx_mcdi_sensor_type[type].hwmon_type;
118 	}
119 	if (!name)
120 		name = "No sensor name available";
121 	EFX_WARN_ON_PARANOID(state >= ARRAY_SIZE(sensor_status_names));
122 	state_txt = sensor_status_names[state];
123 	EFX_WARN_ON_PARANOID(hwmon_type >= EFX_HWMON_TYPES_COUNT);
124 	unit = efx_hwmon_unit[hwmon_type];
125 	if (!unit)
126 		unit = "";
127 
128 	netif_err(efx, hw, efx->net_dev,
129 		  "Sensor %d (%s) reports condition '%s' for value %d%s\n",
130 		  type, name, state_txt, value, unit);
131 }
132 
133 #ifdef CONFIG_SFC_MCDI_MON
134 
135 struct efx_mcdi_mon_attribute {
136 	struct device_attribute dev_attr;
137 	unsigned int index;
138 	unsigned int type;
139 	enum efx_hwmon_type hwmon_type;
140 	unsigned int limit_value;
141 	char name[12];
142 };
143 
144 static int efx_mcdi_mon_update(struct efx_nic *efx)
145 {
146 	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
147 	MCDI_DECLARE_BUF(inbuf, MC_CMD_READ_SENSORS_EXT_IN_LEN);
148 	int rc;
149 
150 	MCDI_SET_QWORD(inbuf, READ_SENSORS_EXT_IN_DMA_ADDR,
151 		       hwmon->dma_buf.dma_addr);
152 	MCDI_SET_DWORD(inbuf, READ_SENSORS_EXT_IN_LENGTH, hwmon->dma_buf.len);
153 
154 	rc = efx_mcdi_rpc(efx, MC_CMD_READ_SENSORS,
155 			  inbuf, sizeof(inbuf), NULL, 0, NULL);
156 	if (rc == 0)
157 		hwmon->last_update = jiffies;
158 	return rc;
159 }
160 
161 static int efx_mcdi_mon_get_entry(struct device *dev, unsigned int index,
162 				  efx_dword_t *entry)
163 {
164 	struct efx_nic *efx = dev_get_drvdata(dev->parent);
165 	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
166 	int rc;
167 
168 	BUILD_BUG_ON(MC_CMD_READ_SENSORS_OUT_LEN != 0);
169 
170 	mutex_lock(&hwmon->update_lock);
171 
172 	/* Use cached value if last update was < 1 s ago */
173 	if (time_before(jiffies, hwmon->last_update + HZ))
174 		rc = 0;
175 	else
176 		rc = efx_mcdi_mon_update(efx);
177 
178 	/* Copy out the requested entry */
179 	*entry = ((efx_dword_t *)hwmon->dma_buf.addr)[index];
180 
181 	mutex_unlock(&hwmon->update_lock);
182 
183 	return rc;
184 }
185 
186 static ssize_t efx_mcdi_mon_show_value(struct device *dev,
187 				       struct device_attribute *attr,
188 				       char *buf)
189 {
190 	struct efx_mcdi_mon_attribute *mon_attr =
191 		container_of(attr, struct efx_mcdi_mon_attribute, dev_attr);
192 	efx_dword_t entry;
193 	unsigned int value, state;
194 	int rc;
195 
196 	rc = efx_mcdi_mon_get_entry(dev, mon_attr->index, &entry);
197 	if (rc)
198 		return rc;
199 
200 	state = EFX_DWORD_FIELD(entry, MC_CMD_SENSOR_VALUE_ENTRY_TYPEDEF_STATE);
201 	if (state == MC_CMD_SENSOR_STATE_NO_READING)
202 		return -EBUSY;
203 
204 	value = EFX_DWORD_FIELD(entry, MC_CMD_SENSOR_VALUE_ENTRY_TYPEDEF_VALUE);
205 
206 	switch (mon_attr->hwmon_type) {
207 	case EFX_HWMON_TEMP:
208 		/* Convert temperature from degrees to milli-degrees Celsius */
209 		value *= 1000;
210 		break;
211 	case EFX_HWMON_POWER:
212 		/* Convert power from watts to microwatts */
213 		value *= 1000000;
214 		break;
215 	default:
216 		/* No conversion needed */
217 		break;
218 	}
219 
220 	return sprintf(buf, "%u\n", value);
221 }
222 
223 static ssize_t efx_mcdi_mon_show_limit(struct device *dev,
224 				       struct device_attribute *attr,
225 				       char *buf)
226 {
227 	struct efx_mcdi_mon_attribute *mon_attr =
228 		container_of(attr, struct efx_mcdi_mon_attribute, dev_attr);
229 	unsigned int value;
230 
231 	value = mon_attr->limit_value;
232 
233 	switch (mon_attr->hwmon_type) {
234 	case EFX_HWMON_TEMP:
235 		/* Convert temperature from degrees to milli-degrees Celsius */
236 		value *= 1000;
237 		break;
238 	case EFX_HWMON_POWER:
239 		/* Convert power from watts to microwatts */
240 		value *= 1000000;
241 		break;
242 	default:
243 		/* No conversion needed */
244 		break;
245 	}
246 
247 	return sprintf(buf, "%u\n", value);
248 }
249 
250 static ssize_t efx_mcdi_mon_show_alarm(struct device *dev,
251 				       struct device_attribute *attr,
252 				       char *buf)
253 {
254 	struct efx_mcdi_mon_attribute *mon_attr =
255 		container_of(attr, struct efx_mcdi_mon_attribute, dev_attr);
256 	efx_dword_t entry;
257 	int state;
258 	int rc;
259 
260 	rc = efx_mcdi_mon_get_entry(dev, mon_attr->index, &entry);
261 	if (rc)
262 		return rc;
263 
264 	state = EFX_DWORD_FIELD(entry, MC_CMD_SENSOR_VALUE_ENTRY_TYPEDEF_STATE);
265 	return sprintf(buf, "%d\n", state != MC_CMD_SENSOR_STATE_OK);
266 }
267 
268 static ssize_t efx_mcdi_mon_show_label(struct device *dev,
269 				       struct device_attribute *attr,
270 				       char *buf)
271 {
272 	struct efx_mcdi_mon_attribute *mon_attr =
273 		container_of(attr, struct efx_mcdi_mon_attribute, dev_attr);
274 	return sprintf(buf, "%s\n",
275 		       efx_mcdi_sensor_type[mon_attr->type].label);
276 }
277 
278 static void
279 efx_mcdi_mon_add_attr(struct efx_nic *efx, const char *name,
280 		      ssize_t (*reader)(struct device *,
281 					struct device_attribute *, char *),
282 		      unsigned int index, unsigned int type,
283 		      unsigned int limit_value)
284 {
285 	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
286 	struct efx_mcdi_mon_attribute *attr = &hwmon->attrs[hwmon->n_attrs];
287 
288 	strscpy(attr->name, name, sizeof(attr->name));
289 	attr->index = index;
290 	attr->type = type;
291 	if (type < ARRAY_SIZE(efx_mcdi_sensor_type))
292 		attr->hwmon_type = efx_mcdi_sensor_type[type].hwmon_type;
293 	else
294 		attr->hwmon_type = EFX_HWMON_UNKNOWN;
295 	attr->limit_value = limit_value;
296 	sysfs_attr_init(&attr->dev_attr.attr);
297 	attr->dev_attr.attr.name = attr->name;
298 	attr->dev_attr.attr.mode = 0444;
299 	attr->dev_attr.show = reader;
300 	hwmon->group.attrs[hwmon->n_attrs++] = &attr->dev_attr.attr;
301 }
302 
303 int efx_mcdi_mon_probe(struct efx_nic *efx)
304 {
305 	unsigned int n_temp = 0, n_cool = 0, n_in = 0, n_curr = 0, n_power = 0;
306 	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
307 	MCDI_DECLARE_BUF(inbuf, MC_CMD_SENSOR_INFO_EXT_IN_LEN);
308 	MCDI_DECLARE_BUF(outbuf, MC_CMD_SENSOR_INFO_OUT_LENMAX);
309 	unsigned int n_pages, n_sensors, n_attrs, page;
310 	size_t outlen;
311 	char name[12];
312 	u32 mask;
313 	int rc, i, j, type;
314 
315 	/* Find out how many sensors are present */
316 	n_sensors = 0;
317 	page = 0;
318 	do {
319 		MCDI_SET_DWORD(inbuf, SENSOR_INFO_EXT_IN_PAGE, page);
320 
321 		rc = efx_mcdi_rpc(efx, MC_CMD_SENSOR_INFO, inbuf, sizeof(inbuf),
322 				  outbuf, sizeof(outbuf), &outlen);
323 		if (rc)
324 			return rc;
325 		if (outlen < MC_CMD_SENSOR_INFO_OUT_LENMIN)
326 			return -EIO;
327 
328 		mask = MCDI_DWORD(outbuf, SENSOR_INFO_OUT_MASK);
329 		n_sensors += hweight32(mask & ~(1 << MC_CMD_SENSOR_PAGE0_NEXT));
330 		++page;
331 	} while (mask & (1 << MC_CMD_SENSOR_PAGE0_NEXT));
332 	n_pages = page;
333 
334 	/* Don't create a device if there are none */
335 	if (n_sensors == 0)
336 		return 0;
337 
338 	rc = efx_nic_alloc_buffer(
339 		efx, &hwmon->dma_buf,
340 		n_sensors * MC_CMD_SENSOR_VALUE_ENTRY_TYPEDEF_LEN,
341 		GFP_KERNEL);
342 	if (rc)
343 		return rc;
344 
345 	mutex_init(&hwmon->update_lock);
346 	efx_mcdi_mon_update(efx);
347 
348 	/* Allocate space for the maximum possible number of
349 	 * attributes for this set of sensors:
350 	 * value, min, max, crit, alarm and label for each sensor.
351 	 */
352 	n_attrs = 6 * n_sensors;
353 	hwmon->attrs = kcalloc(n_attrs, sizeof(*hwmon->attrs), GFP_KERNEL);
354 	if (!hwmon->attrs) {
355 		rc = -ENOMEM;
356 		goto fail;
357 	}
358 	hwmon->group.attrs = kcalloc(n_attrs + 1, sizeof(struct attribute *),
359 				     GFP_KERNEL);
360 	if (!hwmon->group.attrs) {
361 		rc = -ENOMEM;
362 		goto fail;
363 	}
364 
365 	for (i = 0, j = -1, type = -1; ; i++) {
366 		enum efx_hwmon_type hwmon_type;
367 		const char *hwmon_prefix;
368 		unsigned hwmon_index;
369 		u16 min1, max1, min2, max2;
370 
371 		/* Find next sensor type or exit if there is none */
372 		do {
373 			type++;
374 
375 			if ((type % 32) == 0) {
376 				page = type / 32;
377 				j = -1;
378 				if (page == n_pages)
379 					goto hwmon_register;
380 
381 				MCDI_SET_DWORD(inbuf, SENSOR_INFO_EXT_IN_PAGE,
382 					       page);
383 				rc = efx_mcdi_rpc(efx, MC_CMD_SENSOR_INFO,
384 						  inbuf, sizeof(inbuf),
385 						  outbuf, sizeof(outbuf),
386 						  &outlen);
387 				if (rc)
388 					goto fail;
389 				if (outlen < MC_CMD_SENSOR_INFO_OUT_LENMIN) {
390 					rc = -EIO;
391 					goto fail;
392 				}
393 
394 				mask = (MCDI_DWORD(outbuf,
395 						   SENSOR_INFO_OUT_MASK) &
396 					~(1 << MC_CMD_SENSOR_PAGE0_NEXT));
397 
398 				/* Check again for short response */
399 				if (outlen <
400 				    MC_CMD_SENSOR_INFO_OUT_LEN(hweight32(mask))) {
401 					rc = -EIO;
402 					goto fail;
403 				}
404 			}
405 		} while (!(mask & (1 << type % 32)));
406 		j++;
407 
408 		if (type < ARRAY_SIZE(efx_mcdi_sensor_type)) {
409 			hwmon_type = efx_mcdi_sensor_type[type].hwmon_type;
410 
411 			/* Skip sensors specific to a different port */
412 			if (hwmon_type != EFX_HWMON_UNKNOWN &&
413 			    efx_mcdi_sensor_type[type].port >= 0 &&
414 			    efx_mcdi_sensor_type[type].port !=
415 			    efx_port_num(efx))
416 				continue;
417 		} else {
418 			hwmon_type = EFX_HWMON_UNKNOWN;
419 		}
420 
421 		switch (hwmon_type) {
422 		case EFX_HWMON_TEMP:
423 			hwmon_prefix = "temp";
424 			hwmon_index = ++n_temp; /* 1-based */
425 			break;
426 		case EFX_HWMON_COOL:
427 			/* This is likely to be a heatsink, but there
428 			 * is no convention for representing cooling
429 			 * devices other than fans.
430 			 */
431 			hwmon_prefix = "fan";
432 			hwmon_index = ++n_cool; /* 1-based */
433 			break;
434 		default:
435 			hwmon_prefix = "in";
436 			hwmon_index = n_in++; /* 0-based */
437 			break;
438 		case EFX_HWMON_CURR:
439 			hwmon_prefix = "curr";
440 			hwmon_index = ++n_curr; /* 1-based */
441 			break;
442 		case EFX_HWMON_POWER:
443 			hwmon_prefix = "power";
444 			hwmon_index = ++n_power; /* 1-based */
445 			break;
446 		}
447 
448 		min1 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
449 					SENSOR_INFO_ENTRY, j, MIN1);
450 		max1 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
451 					SENSOR_INFO_ENTRY, j, MAX1);
452 		min2 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
453 					SENSOR_INFO_ENTRY, j, MIN2);
454 		max2 = MCDI_ARRAY_FIELD(outbuf, SENSOR_ENTRY,
455 					SENSOR_INFO_ENTRY, j, MAX2);
456 
457 		if (min1 != max1) {
458 			snprintf(name, sizeof(name), "%s%u_input",
459 				 hwmon_prefix, hwmon_index);
460 			efx_mcdi_mon_add_attr(
461 				efx, name, efx_mcdi_mon_show_value, i, type, 0);
462 
463 			if (hwmon_type != EFX_HWMON_POWER) {
464 				snprintf(name, sizeof(name), "%s%u_min",
465 					 hwmon_prefix, hwmon_index);
466 				efx_mcdi_mon_add_attr(
467 					efx, name, efx_mcdi_mon_show_limit,
468 					i, type, min1);
469 			}
470 
471 			snprintf(name, sizeof(name), "%s%u_max",
472 				 hwmon_prefix, hwmon_index);
473 			efx_mcdi_mon_add_attr(
474 				efx, name, efx_mcdi_mon_show_limit,
475 				i, type, max1);
476 
477 			if (min2 != max2) {
478 				/* Assume max2 is critical value.
479 				 * But we have no good way to expose min2.
480 				 */
481 				snprintf(name, sizeof(name), "%s%u_crit",
482 					 hwmon_prefix, hwmon_index);
483 				efx_mcdi_mon_add_attr(
484 					efx, name, efx_mcdi_mon_show_limit,
485 					i, type, max2);
486 			}
487 		}
488 
489 		snprintf(name, sizeof(name), "%s%u_alarm",
490 			 hwmon_prefix, hwmon_index);
491 		efx_mcdi_mon_add_attr(
492 			efx, name, efx_mcdi_mon_show_alarm, i, type, 0);
493 
494 		if (type < ARRAY_SIZE(efx_mcdi_sensor_type) &&
495 		    efx_mcdi_sensor_type[type].label) {
496 			snprintf(name, sizeof(name), "%s%u_label",
497 				 hwmon_prefix, hwmon_index);
498 			efx_mcdi_mon_add_attr(
499 				efx, name, efx_mcdi_mon_show_label, i, type, 0);
500 		}
501 	}
502 
503 hwmon_register:
504 	hwmon->groups[0] = &hwmon->group;
505 	hwmon->device = hwmon_device_register_with_groups(&efx->pci_dev->dev,
506 							  KBUILD_MODNAME, NULL,
507 							  hwmon->groups);
508 	if (IS_ERR(hwmon->device)) {
509 		rc = PTR_ERR(hwmon->device);
510 		goto fail;
511 	}
512 
513 	return 0;
514 
515 fail:
516 	efx_mcdi_mon_remove(efx);
517 	return rc;
518 }
519 
520 void efx_mcdi_mon_remove(struct efx_nic *efx)
521 {
522 	struct efx_mcdi_mon *hwmon = efx_mcdi_mon(efx);
523 
524 	if (hwmon->device)
525 		hwmon_device_unregister(hwmon->device);
526 	kfree(hwmon->attrs);
527 	kfree(hwmon->group.attrs);
528 	efx_nic_free_buffer(efx, &hwmon->dma_buf);
529 }
530 
531 #endif /* CONFIG_SFC_MCDI_MON */
532