1 /* $NetBSD: apple_smc_temp.c,v 1.7 2023/08/08 05:20:14 mrg Exp $ */
2
3 /*
4 * Apple System Management Controller: Temperature Sensors
5 */
6
7 /*-
8 * Copyright (c) 2013 The NetBSD Foundation, Inc.
9 * All rights reserved.
10 *
11 * This code is derived from software contributed to The NetBSD Foundation
12 * by Taylor R. Campbell.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 * 2. Redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in the
21 * documentation and/or other materials provided with the distribution.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
24 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
25 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
27 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33 * POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: apple_smc_temp.c,v 1.7 2023/08/08 05:20:14 mrg Exp $");
38
39 #include <sys/types.h>
40 #include <sys/param.h>
41 #include <sys/device.h>
42 #include <sys/kmem.h>
43 #include <sys/module.h>
44 #include <sys/systm.h>
45
46 #include <dev/ic/apple_smc.h>
47
48 #include <dev/sysmon/sysmonvar.h>
49
50 struct apple_smc_temp_softc {
51 device_t sc_dev;
52 struct apple_smc_tag *sc_smc;
53 struct sysmon_envsys *sc_sme;
54 struct {
55 struct apple_smc_key *sensor_key;
56 struct envsys_data sensor_data;
57 } *sc_sensors;
58 size_t sc_nsensors;
59 };
60
61 static int apple_smc_temp_match(device_t, cfdata_t, void *);
62 static void apple_smc_temp_attach(device_t, device_t, void *);
63 static int apple_smc_temp_detach(device_t, int);
64 static void apple_smc_temp_refresh(struct sysmon_envsys *,
65 struct envsys_data *);
66 static int apple_smc_temp_count_sensors(struct apple_smc_tag *,
67 uint32_t *);
68 static void apple_smc_temp_count_sensors_scanner(struct apple_smc_tag *,
69 void *, struct apple_smc_key *);
70 static int apple_smc_temp_find_sensors(struct apple_smc_temp_softc *);
71 static int apple_smc_temp_find_sensors_init(struct apple_smc_tag *,
72 void *, uint32_t);
73 static void apple_smc_temp_find_sensors_scanner(struct apple_smc_tag *,
74 void *, struct apple_smc_key *);
75 static void apple_smc_temp_release_keys(struct apple_smc_temp_softc *);
76 static int apple_smc_scan_temp_sensors(struct apple_smc_tag *, void *,
77 int (*)(struct apple_smc_tag *, void *, uint32_t),
78 void (*)(struct apple_smc_tag *, void *,
79 struct apple_smc_key *));
80 static int apple_smc_bound_temp_sensors(struct apple_smc_tag *,
81 uint32_t *, uint32_t *);
82 static bool apple_smc_temp_sensor_p(const struct apple_smc_key *);
83
84 CFATTACH_DECL_NEW(apple_smc_temp, sizeof(struct apple_smc_temp_softc),
85 apple_smc_temp_match, apple_smc_temp_attach, apple_smc_temp_detach, NULL);
86
87 static int
apple_smc_temp_match(device_t parent,cfdata_t match,void * aux)88 apple_smc_temp_match(device_t parent, cfdata_t match, void *aux)
89 {
90 const struct apple_smc_attach_args *const asa = aux;
91 uint32_t nsensors;
92 int error;
93
94 /* Find how many temperature sensors we have. */
95 error = apple_smc_temp_count_sensors(asa->asa_smc, &nsensors);
96 if (error)
97 return 0;
98
99 /* If there aren't any, don't bother attaching. */
100 if (nsensors == 0)
101 return 0;
102
103 return 1;
104 }
105
106 static void
apple_smc_temp_attach(device_t parent,device_t self,void * aux)107 apple_smc_temp_attach(device_t parent, device_t self, void *aux)
108 {
109 struct apple_smc_temp_softc *const sc = device_private(self);
110 const struct apple_smc_attach_args *const asa = aux;
111 int error;
112
113 /* Identify ourselves. */
114 aprint_normal(": Apple SMC temperature sensors\n");
115
116 /* Initialize the softc. */
117 sc->sc_dev = self;
118 sc->sc_smc = asa->asa_smc;
119
120 /* Create a sysmon_envsys record, but don't register it yet. */
121 sc->sc_sme = sysmon_envsys_create();
122 sc->sc_sme->sme_name = device_xname(self);
123 sc->sc_sme->sme_cookie = sc;
124 sc->sc_sme->sme_refresh = apple_smc_temp_refresh;
125
126 /* Find and attach all the sensors. */
127 error = apple_smc_temp_find_sensors(sc);
128 if (error) {
129 aprint_error_dev(self, "failed to find sensors: %d\n", error);
130 goto fail;
131 }
132
133 /* Sensors are all attached. Register with sysmon_envsys now. */
134 error = sysmon_envsys_register(sc->sc_sme);
135 if (error) {
136 aprint_error_dev(self, "failed to register with sysmon_envsys:"
137 " %d\n", error);
138 goto fail;
139 }
140
141 /* Success! */
142 return;
143
144 fail: sysmon_envsys_destroy(sc->sc_sme);
145 sc->sc_sme = NULL;
146 }
147
148 static int
apple_smc_temp_detach(device_t self,int flags)149 apple_smc_temp_detach(device_t self, int flags)
150 {
151 struct apple_smc_temp_softc *const sc = device_private(self);
152
153 /* If we registered with sysmon_envsys, unregister. */
154 if (sc->sc_sme != NULL) {
155 sysmon_envsys_unregister(sc->sc_sme);
156
157 KASSERT(sc->sc_sensors != NULL);
158 KASSERT(sc->sc_nsensors > 0);
159
160 /* Release the keys and free the memory for sensor records. */
161 apple_smc_temp_release_keys(sc);
162 kmem_free(sc->sc_sensors,
163 (sizeof(sc->sc_sensors[0]) * sc->sc_nsensors));
164 sc->sc_sensors = NULL;
165 sc->sc_nsensors = 0;
166 }
167
168 /* Success! */
169 return 0;
170 }
171
172 static void
apple_smc_temp_refresh(struct sysmon_envsys * sme,struct envsys_data * edata)173 apple_smc_temp_refresh(struct sysmon_envsys *sme, struct envsys_data *edata)
174 {
175 struct apple_smc_temp_softc *const sc = sme->sme_cookie;
176 const struct apple_smc_key *key;
177 uint16_t utemp16;
178 int32_t temp;
179 int error;
180
181 /* Sanity-check the sensor number out of paranoia. */
182 if (edata->sensor >= sc->sc_nsensors) {
183 aprint_error_dev(sc->sc_dev, "unknown sensor %"PRIu32"\n",
184 edata->sensor);
185 return;
186 }
187
188 /* Read the raw temperature sensor value. */
189 key = sc->sc_sensors[edata->sensor].sensor_key;
190 KASSERT(key != NULL);
191 error = apple_smc_read_key_2(sc->sc_smc, key, &utemp16);
192 if (error) {
193 aprint_error_dev(sc->sc_dev,
194 "failed to read temperature sensor %"PRIu32" (%s): %d\n",
195 edata->sensor, apple_smc_key_name(key), error);
196 edata->state = ENVSYS_SINVALID;
197 return;
198 }
199
200 /* Sign-extend, in case we ever get below freezing... */
201 temp = (int16_t)utemp16;
202
203 /* Convert to `millicentigrade'. */
204 temp *= 250;
205 temp >>= 6;
206
207 /* Convert to millikelvins. */
208 temp += 273150;
209
210 /* Finally, convert to microkelvins as sysmon_envsys wants. */
211 temp *= 1000;
212
213 /* Success! */
214 edata->value_cur = temp;
215 edata->state = ENVSYS_SVALID;
216 }
217
218 static int
apple_smc_temp_count_sensors(struct apple_smc_tag * smc,uint32_t * nsensors)219 apple_smc_temp_count_sensors(struct apple_smc_tag *smc, uint32_t *nsensors)
220 {
221
222 /* Start with zero sensors. */
223 *nsensors = 0;
224
225 /* Count 'em. */
226 return apple_smc_scan_temp_sensors(smc, nsensors,
227 NULL,
228 &apple_smc_temp_count_sensors_scanner);
229 }
230
231 static void
apple_smc_temp_count_sensors_scanner(struct apple_smc_tag * smc,void * arg,struct apple_smc_key * key)232 apple_smc_temp_count_sensors_scanner(struct apple_smc_tag *smc, void *arg,
233 struct apple_smc_key *key)
234 {
235 uint32_t *const nsensors = arg;
236
237 (*nsensors)++;
238 apple_smc_release_key(smc, key);
239 }
240
241 struct fss { /* Find Sensors State */
242 struct apple_smc_temp_softc *fss_sc;
243 unsigned int fss_sensor;
244 };
245
246 static int
apple_smc_temp_find_sensors(struct apple_smc_temp_softc * sc)247 apple_smc_temp_find_sensors(struct apple_smc_temp_softc *sc)
248 {
249 struct fss fss;
250 int error;
251
252 /* Start with zero sensors. */
253 fss.fss_sc = sc;
254 fss.fss_sensor = 0;
255
256 /* Find 'em. */
257 error = apple_smc_scan_temp_sensors(sc->sc_smc, &fss,
258 &apple_smc_temp_find_sensors_init,
259 &apple_smc_temp_find_sensors_scanner);
260 if (error)
261 return error;
262
263 /*
264 * Success guarantees that sc->sc_nsensors will be nonzero and
265 * sc->sc_sensors will be allocated.
266 */
267 KASSERT(sc->sc_sensors != NULL);
268 KASSERT(sc->sc_nsensors > 0);
269
270 /* If we didn't find any sensors, bail. */
271 if (fss.fss_sensor == 0) {
272 kmem_free(sc->sc_sensors, sc->sc_nsensors);
273 sc->sc_sensors = NULL;
274 sc->sc_nsensors = 0;
275 return EIO;
276 }
277
278 /* Shrink the array if we overshot. */
279 if (fss.fss_sensor < sc->sc_nsensors) {
280 void *const sensors = kmem_alloc((fss.fss_sensor *
281 sizeof(sc->sc_sensors[0])), KM_SLEEP);
282
283 (void)memcpy(sensors, sc->sc_sensors,
284 (fss.fss_sensor * sizeof(sc->sc_sensors[0])));
285 kmem_free(sc->sc_sensors, sc->sc_nsensors);
286 sc->sc_sensors = sensors;
287 sc->sc_nsensors = fss.fss_sensor;
288 }
289
290 /* Success! */
291 return 0;
292 }
293
294 static int
apple_smc_temp_find_sensors_init(struct apple_smc_tag * smc,void * arg,uint32_t nsensors)295 apple_smc_temp_find_sensors_init(struct apple_smc_tag *smc, void *arg,
296 uint32_t nsensors)
297 {
298 struct fss *const fss = arg;
299
300 /* Record the maximum number of sensors we may have. */
301 fss->fss_sc->sc_nsensors = nsensors;
302
303 /* If we found a maximum of zero sensors, bail. */
304 if (nsensors == 0) {
305 fss->fss_sc->sc_sensors = NULL;
306 return EIO;
307 }
308
309 /*
310 * If there may be any sensors, optimistically allocate as many
311 * records for them as we may possibly need.
312 */
313 fss->fss_sc->sc_sensors = kmem_alloc((nsensors *
314 sizeof(fss->fss_sc->sc_sensors[0])), KM_SLEEP);
315
316 /* Success! */
317 return 0;
318 }
319
320 static void
apple_smc_temp_find_sensors_scanner(struct apple_smc_tag * smc,void * arg,struct apple_smc_key * key)321 apple_smc_temp_find_sensors_scanner(struct apple_smc_tag *smc, void *arg,
322 struct apple_smc_key *key)
323 {
324 struct fss *const fss = arg;
325 const uint32_t sensor = fss->fss_sensor;
326 struct envsys_data *const edata =
327 &fss->fss_sc->sc_sensors[sensor].sensor_data;
328 int error;
329
330 /* Initialize the envsys_data record for this temperature sensor. */
331 edata->units = ENVSYS_STEMP;
332 edata->state = ENVSYS_SINVALID;
333 edata->flags = ENVSYS_FHAS_ENTROPY;
334
335 /*
336 * Use the SMC key name as the temperature sensor's name.
337 *
338 * XXX We ought to use a more meaningful name based on a table
339 * of known temperature sensors.
340 */
341 CTASSERT(sizeof(edata->desc) >= 4);
342 (void)strlcpy(edata->desc, apple_smc_key_name(key), 4);
343
344 /* Attach this temperature sensor to sysmon_envsys. */
345 error = sysmon_envsys_sensor_attach(fss->fss_sc->sc_sme, edata);
346 if (error) {
347 aprint_error_dev(fss->fss_sc->sc_dev,
348 "failed to attach temperature sensor %s: %d\n",
349 apple_smc_key_name(key), error);
350 return;
351 }
352
353 /* Success! */
354 fss->fss_sc->sc_sensors[sensor].sensor_key = key;
355 fss->fss_sensor++;
356 }
357
358 static void
apple_smc_temp_release_keys(struct apple_smc_temp_softc * sc)359 apple_smc_temp_release_keys(struct apple_smc_temp_softc *sc)
360 {
361 uint32_t sensor;
362
363 for (sensor = 0; sensor < sc->sc_nsensors; sensor++) {
364 KASSERT(sc->sc_sensors[sensor].sensor_key != NULL);
365 apple_smc_release_key(sc->sc_smc,
366 sc->sc_sensors[sensor].sensor_key);
367 }
368 }
369
370 static int
apple_smc_scan_temp_sensors(struct apple_smc_tag * smc,void * arg,int (* init)(struct apple_smc_tag *,void *,uint32_t),void (* scanner)(struct apple_smc_tag *,void *,struct apple_smc_key *))371 apple_smc_scan_temp_sensors(struct apple_smc_tag *smc, void *arg,
372 int (*init)(struct apple_smc_tag *, void *, uint32_t),
373 void (*scanner)(struct apple_smc_tag *, void *, struct apple_smc_key *))
374 {
375 uint32_t tstart, ustart, i;
376 struct apple_smc_key *key;
377 int error;
378
379 /* Find [start, end) bounds on the temperature sensor key indices. */
380 error = apple_smc_bound_temp_sensors(smc, &tstart, &ustart);
381 if (error)
382 return error;
383 KASSERT(tstart <= ustart);
384
385 /* Inform the caller of the number of candidates. */
386 if (init != NULL) {
387 error = (*init)(smc, arg, (ustart - tstart));
388 if (error)
389 return error;
390 }
391
392 /* Take a closer look at all the candidates. */
393 for (i = tstart; i < ustart; i++) {
394 error = apple_smc_nth_key(smc, i, NULL, &key);
395 if (error)
396 continue;
397
398 /* Skip it if it's not a temperature sensor. */
399 if (!apple_smc_temp_sensor_p(key)) {
400 apple_smc_release_key(smc, key);
401 continue;
402 }
403
404 /* Scan it if it is one. */
405 (*scanner)(smc, arg, key);
406 }
407
408 /* Success! */
409 return 0;
410 }
411
412 static bool
apple_smc_temp_sensor_p(const struct apple_smc_key * key)413 apple_smc_temp_sensor_p(const struct apple_smc_key *key)
414 {
415
416 /* It's a temperature sensor iff its type is sp78. */
417 return (0 == memcmp(apple_smc_key_desc(key)->asd_type,
418 APPLE_SMC_TYPE_SP78, 4));
419 }
420
421 static int
apple_smc_bound_temp_sensors(struct apple_smc_tag * smc,uint32_t * tstart,uint32_t * ustart)422 apple_smc_bound_temp_sensors(struct apple_smc_tag *smc, uint32_t *tstart,
423 uint32_t *ustart)
424 {
425 int error;
426
427 /* Find the first `T...' key. */
428 error = apple_smc_key_search(smc, "T\0\0\0", tstart);
429 if (error)
430 return error;
431
432 /* Find the first `U...' key. */
433 error = apple_smc_key_search(smc, "U\0\0\0", ustart);
434 if (error)
435 return error;
436
437 /* Sanity check: `T...' keys had better precede `U...' keys. */
438 if (!(*tstart <= *ustart))
439 return EIO;
440
441 /* Success! */
442 return 0;
443 }
444
445 MODULE(MODULE_CLASS_DRIVER, apple_smc_temp, "apple_smc,sysmon_envsys");
446
447 #ifdef _MODULE
448 #include "ioconf.c"
449 #endif
450
451 static int
apple_smc_temp_modcmd(modcmd_t cmd,void * arg __unused)452 apple_smc_temp_modcmd(modcmd_t cmd, void *arg __unused)
453 {
454 #ifdef _MODULE
455 int error;
456 #endif
457
458 switch (cmd) {
459 case MODULE_CMD_INIT:
460 #ifdef _MODULE
461 error = config_init_component(cfdriver_ioconf_apple_smc_temp,
462 cfattach_ioconf_apple_smc_temp,
463 cfdata_ioconf_apple_smc_temp);
464 if (error)
465 return error;
466 #endif
467 return 0;
468
469 case MODULE_CMD_FINI:
470 #ifdef _MODULE
471 error = config_fini_component(cfdriver_ioconf_apple_smc_temp,
472 cfattach_ioconf_apple_smc_temp,
473 cfdata_ioconf_apple_smc_temp);
474 if (error)
475 return error;
476 #endif
477 return 0;
478
479 default:
480 return ENOTTY;
481 }
482 }
483