1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Windfarm PowerMac thermal control.
4 * Control loops for RackMack3,1 (Xserve G5)
5 *
6 * Copyright (C) 2012 Benjamin Herrenschmidt, IBM Corp.
7 */
8 #include <linux/types.h>
9 #include <linux/errno.h>
10 #include <linux/kernel.h>
11 #include <linux/device.h>
12 #include <linux/platform_device.h>
13 #include <linux/reboot.h>
14
15 #include <asm/smu.h>
16
17 #include "windfarm.h"
18 #include "windfarm_pid.h"
19 #include "windfarm_mpu.h"
20
21 #define VERSION "1.0"
22
23 #undef DEBUG
24 #undef LOTSA_DEBUG
25
26 #ifdef DEBUG
27 #define DBG(args...) printk(args)
28 #else
29 #define DBG(args...) do { } while(0)
30 #endif
31
32 #ifdef LOTSA_DEBUG
33 #define DBG_LOTS(args...) printk(args)
34 #else
35 #define DBG_LOTS(args...) do { } while(0)
36 #endif
37
38 /* define this to force CPU overtemp to 60 degree, useful for testing
39 * the overtemp code
40 */
41 #undef HACKED_OVERTEMP
42
43 /* We currently only handle 2 chips */
44 #define NR_CHIPS 2
45 #define NR_CPU_FANS 3 * NR_CHIPS
46
47 /* Controls and sensors */
48 static struct wf_sensor *sens_cpu_temp[NR_CHIPS];
49 static struct wf_sensor *sens_cpu_volts[NR_CHIPS];
50 static struct wf_sensor *sens_cpu_amps[NR_CHIPS];
51 static struct wf_sensor *backside_temp;
52 static struct wf_sensor *slots_temp;
53 static struct wf_sensor *dimms_temp;
54
55 static struct wf_control *cpu_fans[NR_CHIPS][3];
56 static struct wf_control *backside_fan;
57 static struct wf_control *slots_fan;
58 static struct wf_control *cpufreq_clamp;
59
60 /* We keep a temperature history for average calculation of 180s */
61 #define CPU_TEMP_HIST_SIZE 180
62
63 /* PID loop state */
64 static const struct mpu_data *cpu_mpu_data[NR_CHIPS];
65 static struct wf_cpu_pid_state cpu_pid[NR_CHIPS];
66 static u32 cpu_thist[CPU_TEMP_HIST_SIZE];
67 static int cpu_thist_pt;
68 static s64 cpu_thist_total;
69 static s32 cpu_all_tmax = 100 << 16;
70 static struct wf_pid_state backside_pid;
71 static int backside_tick;
72 static struct wf_pid_state slots_pid;
73 static int slots_tick;
74 static int slots_speed;
75 static struct wf_pid_state dimms_pid;
76 static int dimms_output_clamp;
77
78 static int nr_chips;
79 static bool have_all_controls;
80 static bool have_all_sensors;
81 static bool started;
82
83 static int failure_state;
84 #define FAILURE_SENSOR 1
85 #define FAILURE_FAN 2
86 #define FAILURE_PERM 4
87 #define FAILURE_LOW_OVERTEMP 8
88 #define FAILURE_HIGH_OVERTEMP 16
89
90 /* Overtemp values */
91 #define LOW_OVER_AVERAGE 0
92 #define LOW_OVER_IMMEDIATE (10 << 16)
93 #define LOW_OVER_CLEAR ((-10) << 16)
94 #define HIGH_OVER_IMMEDIATE (14 << 16)
95 #define HIGH_OVER_AVERAGE (10 << 16)
96 #define HIGH_OVER_IMMEDIATE (14 << 16)
97
98
cpu_max_all_fans(void)99 static void cpu_max_all_fans(void)
100 {
101 int i;
102
103 /* We max all CPU fans in case of a sensor error. We also do the
104 * cpufreq clamping now, even if it's supposedly done later by the
105 * generic code anyway, we do it earlier here to react faster
106 */
107 if (cpufreq_clamp)
108 wf_control_set_max(cpufreq_clamp);
109 for (i = 0; i < nr_chips; i++) {
110 if (cpu_fans[i][0])
111 wf_control_set_max(cpu_fans[i][0]);
112 if (cpu_fans[i][1])
113 wf_control_set_max(cpu_fans[i][1]);
114 if (cpu_fans[i][2])
115 wf_control_set_max(cpu_fans[i][2]);
116 }
117 }
118
cpu_check_overtemp(s32 temp)119 static int cpu_check_overtemp(s32 temp)
120 {
121 int new_state = 0;
122 s32 t_avg, t_old;
123 static bool first = true;
124
125 /* First check for immediate overtemps */
126 if (temp >= (cpu_all_tmax + LOW_OVER_IMMEDIATE)) {
127 new_state |= FAILURE_LOW_OVERTEMP;
128 if ((failure_state & FAILURE_LOW_OVERTEMP) == 0)
129 printk(KERN_ERR "windfarm: Overtemp due to immediate CPU"
130 " temperature !\n");
131 }
132 if (temp >= (cpu_all_tmax + HIGH_OVER_IMMEDIATE)) {
133 new_state |= FAILURE_HIGH_OVERTEMP;
134 if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0)
135 printk(KERN_ERR "windfarm: Critical overtemp due to"
136 " immediate CPU temperature !\n");
137 }
138
139 /*
140 * The first time around, initialize the array with the first
141 * temperature reading
142 */
143 if (first) {
144 int i;
145
146 cpu_thist_total = 0;
147 for (i = 0; i < CPU_TEMP_HIST_SIZE; i++) {
148 cpu_thist[i] = temp;
149 cpu_thist_total += temp;
150 }
151 first = false;
152 }
153
154 /*
155 * We calculate a history of max temperatures and use that for the
156 * overtemp management
157 */
158 t_old = cpu_thist[cpu_thist_pt];
159 cpu_thist[cpu_thist_pt] = temp;
160 cpu_thist_pt = (cpu_thist_pt + 1) % CPU_TEMP_HIST_SIZE;
161 cpu_thist_total -= t_old;
162 cpu_thist_total += temp;
163 t_avg = cpu_thist_total / CPU_TEMP_HIST_SIZE;
164
165 DBG_LOTS(" t_avg = %d.%03d (out: %d.%03d, in: %d.%03d)\n",
166 FIX32TOPRINT(t_avg), FIX32TOPRINT(t_old), FIX32TOPRINT(temp));
167
168 /* Now check for average overtemps */
169 if (t_avg >= (cpu_all_tmax + LOW_OVER_AVERAGE)) {
170 new_state |= FAILURE_LOW_OVERTEMP;
171 if ((failure_state & FAILURE_LOW_OVERTEMP) == 0)
172 printk(KERN_ERR "windfarm: Overtemp due to average CPU"
173 " temperature !\n");
174 }
175 if (t_avg >= (cpu_all_tmax + HIGH_OVER_AVERAGE)) {
176 new_state |= FAILURE_HIGH_OVERTEMP;
177 if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0)
178 printk(KERN_ERR "windfarm: Critical overtemp due to"
179 " average CPU temperature !\n");
180 }
181
182 /* Now handle overtemp conditions. We don't currently use the windfarm
183 * overtemp handling core as it's not fully suited to the needs of those
184 * new machine. This will be fixed later.
185 */
186 if (new_state) {
187 /* High overtemp -> immediate shutdown */
188 if (new_state & FAILURE_HIGH_OVERTEMP)
189 machine_power_off();
190 if ((failure_state & new_state) != new_state)
191 cpu_max_all_fans();
192 failure_state |= new_state;
193 } else if ((failure_state & FAILURE_LOW_OVERTEMP) &&
194 (temp < (cpu_all_tmax + LOW_OVER_CLEAR))) {
195 printk(KERN_ERR "windfarm: Overtemp condition cleared !\n");
196 failure_state &= ~FAILURE_LOW_OVERTEMP;
197 }
198
199 return failure_state & (FAILURE_LOW_OVERTEMP | FAILURE_HIGH_OVERTEMP);
200 }
201
read_one_cpu_vals(int cpu,s32 * temp,s32 * power)202 static int read_one_cpu_vals(int cpu, s32 *temp, s32 *power)
203 {
204 s32 dtemp, volts, amps;
205 int rc;
206
207 /* Get diode temperature */
208 rc = wf_sensor_get(sens_cpu_temp[cpu], &dtemp);
209 if (rc) {
210 DBG(" CPU%d: temp reading error !\n", cpu);
211 return -EIO;
212 }
213 DBG_LOTS(" CPU%d: temp = %d.%03d\n", cpu, FIX32TOPRINT((dtemp)));
214 *temp = dtemp;
215
216 /* Get voltage */
217 rc = wf_sensor_get(sens_cpu_volts[cpu], &volts);
218 if (rc) {
219 DBG(" CPU%d, volts reading error !\n", cpu);
220 return -EIO;
221 }
222 DBG_LOTS(" CPU%d: volts = %d.%03d\n", cpu, FIX32TOPRINT((volts)));
223
224 /* Get current */
225 rc = wf_sensor_get(sens_cpu_amps[cpu], &s);
226 if (rc) {
227 DBG(" CPU%d, current reading error !\n", cpu);
228 return -EIO;
229 }
230 DBG_LOTS(" CPU%d: amps = %d.%03d\n", cpu, FIX32TOPRINT((amps)));
231
232 /* Calculate power */
233
234 /* Scale voltage and current raw sensor values according to fixed scales
235 * obtained in Darwin and calculate power from I and V
236 */
237 *power = (((u64)volts) * ((u64)amps)) >> 16;
238
239 DBG_LOTS(" CPU%d: power = %d.%03d\n", cpu, FIX32TOPRINT((*power)));
240
241 return 0;
242
243 }
244
cpu_fans_tick(void)245 static void cpu_fans_tick(void)
246 {
247 int err, cpu, i;
248 s32 speed, temp, power, t_max = 0;
249
250 DBG_LOTS("* cpu fans_tick_split()\n");
251
252 for (cpu = 0; cpu < nr_chips; ++cpu) {
253 struct wf_cpu_pid_state *sp = &cpu_pid[cpu];
254
255 /* Read current speed */
256 wf_control_get(cpu_fans[cpu][0], &sp->target);
257
258 err = read_one_cpu_vals(cpu, &temp, &power);
259 if (err) {
260 failure_state |= FAILURE_SENSOR;
261 cpu_max_all_fans();
262 return;
263 }
264
265 /* Keep track of highest temp */
266 t_max = max(t_max, temp);
267
268 /* Handle possible overtemps */
269 if (cpu_check_overtemp(t_max))
270 return;
271
272 /* Run PID */
273 wf_cpu_pid_run(sp, power, temp);
274
275 DBG_LOTS(" CPU%d: target = %d RPM\n", cpu, sp->target);
276
277 /* Apply DIMMs clamp */
278 speed = max(sp->target, dimms_output_clamp);
279
280 /* Apply result to all cpu fans */
281 for (i = 0; i < 3; i++) {
282 err = wf_control_set(cpu_fans[cpu][i], speed);
283 if (err) {
284 pr_warn("wf_rm31: Fan %s reports error %d\n",
285 cpu_fans[cpu][i]->name, err);
286 failure_state |= FAILURE_FAN;
287 }
288 }
289 }
290 }
291
292 /* Implementation... */
cpu_setup_pid(int cpu)293 static int cpu_setup_pid(int cpu)
294 {
295 struct wf_cpu_pid_param pid;
296 const struct mpu_data *mpu = cpu_mpu_data[cpu];
297 s32 tmax, ttarget, ptarget;
298 int fmin, fmax, hsize;
299
300 /* Get PID params from the appropriate MPU EEPROM */
301 tmax = mpu->tmax << 16;
302 ttarget = mpu->ttarget << 16;
303 ptarget = ((s32)(mpu->pmaxh - mpu->padjmax)) << 16;
304
305 DBG("wf_72: CPU%d ttarget = %d.%03d, tmax = %d.%03d\n",
306 cpu, FIX32TOPRINT(ttarget), FIX32TOPRINT(tmax));
307
308 /* We keep a global tmax for overtemp calculations */
309 if (tmax < cpu_all_tmax)
310 cpu_all_tmax = tmax;
311
312 /* Set PID min/max by using the rear fan min/max */
313 fmin = wf_control_get_min(cpu_fans[cpu][0]);
314 fmax = wf_control_get_max(cpu_fans[cpu][0]);
315 DBG("wf_72: CPU%d max RPM range = [%d..%d]\n", cpu, fmin, fmax);
316
317 /* History size */
318 hsize = min_t(int, mpu->tguardband, WF_PID_MAX_HISTORY);
319 DBG("wf_72: CPU%d history size = %d\n", cpu, hsize);
320
321 /* Initialize PID loop */
322 pid.interval = 1; /* seconds */
323 pid.history_len = hsize;
324 pid.gd = mpu->pid_gd;
325 pid.gp = mpu->pid_gp;
326 pid.gr = mpu->pid_gr;
327 pid.tmax = tmax;
328 pid.ttarget = ttarget;
329 pid.pmaxadj = ptarget;
330 pid.min = fmin;
331 pid.max = fmax;
332
333 wf_cpu_pid_init(&cpu_pid[cpu], &pid);
334 cpu_pid[cpu].target = 4000;
335
336 return 0;
337 }
338
339 /* Backside/U3 fan */
340 static const struct wf_pid_param backside_param = {
341 .interval = 1,
342 .history_len = 2,
343 .gd = 0x00500000,
344 .gp = 0x0004cccc,
345 .gr = 0,
346 .itarget = 70 << 16,
347 .additive = 0,
348 .min = 20,
349 .max = 100,
350 };
351
352 /* DIMMs temperature (clamp the backside fan) */
353 static const struct wf_pid_param dimms_param = {
354 .interval = 1,
355 .history_len = 20,
356 .gd = 0,
357 .gp = 0,
358 .gr = 0x06553600,
359 .itarget = 50 << 16,
360 .additive = 0,
361 .min = 4000,
362 .max = 14000,
363 };
364
backside_fan_tick(void)365 static void backside_fan_tick(void)
366 {
367 s32 temp, dtemp;
368 int speed, dspeed, fan_min;
369 int err;
370
371 if (!backside_fan || !backside_temp || !dimms_temp || !backside_tick)
372 return;
373 if (--backside_tick > 0)
374 return;
375 backside_tick = backside_pid.param.interval;
376
377 DBG_LOTS("* backside fans tick\n");
378
379 /* Update fan speed from actual fans */
380 err = wf_control_get(backside_fan, &speed);
381 if (!err)
382 backside_pid.target = speed;
383
384 err = wf_sensor_get(backside_temp, &temp);
385 if (err) {
386 printk(KERN_WARNING "windfarm: U3 temp sensor error %d\n",
387 err);
388 failure_state |= FAILURE_SENSOR;
389 wf_control_set_max(backside_fan);
390 return;
391 }
392 speed = wf_pid_run(&backside_pid, temp);
393
394 DBG_LOTS("backside PID temp=%d.%.3d speed=%d\n",
395 FIX32TOPRINT(temp), speed);
396
397 err = wf_sensor_get(dimms_temp, &dtemp);
398 if (err) {
399 printk(KERN_WARNING "windfarm: DIMMs temp sensor error %d\n",
400 err);
401 failure_state |= FAILURE_SENSOR;
402 wf_control_set_max(backside_fan);
403 return;
404 }
405 dspeed = wf_pid_run(&dimms_pid, dtemp);
406 dimms_output_clamp = dspeed;
407
408 fan_min = (dspeed * 100) / 14000;
409 fan_min = max(fan_min, backside_param.min);
410 speed = max(speed, fan_min);
411
412 err = wf_control_set(backside_fan, speed);
413 if (err) {
414 printk(KERN_WARNING "windfarm: backside fan error %d\n", err);
415 failure_state |= FAILURE_FAN;
416 }
417 }
418
backside_setup_pid(void)419 static void backside_setup_pid(void)
420 {
421 /* first time initialize things */
422 s32 fmin = wf_control_get_min(backside_fan);
423 s32 fmax = wf_control_get_max(backside_fan);
424 struct wf_pid_param param;
425
426 param = backside_param;
427 param.min = max(param.min, fmin);
428 param.max = min(param.max, fmax);
429 wf_pid_init(&backside_pid, ¶m);
430
431 param = dimms_param;
432 wf_pid_init(&dimms_pid, ¶m);
433
434 backside_tick = 1;
435
436 pr_info("wf_rm31: Backside control loop started.\n");
437 }
438
439 /* Slots fan */
440 static const struct wf_pid_param slots_param = {
441 .interval = 1,
442 .history_len = 20,
443 .gd = 0,
444 .gp = 0,
445 .gr = 0x00100000,
446 .itarget = 3200000,
447 .additive = 0,
448 .min = 20,
449 .max = 100,
450 };
451
slots_fan_tick(void)452 static void slots_fan_tick(void)
453 {
454 s32 temp;
455 int speed;
456 int err;
457
458 if (!slots_fan || !slots_temp || !slots_tick)
459 return;
460 if (--slots_tick > 0)
461 return;
462 slots_tick = slots_pid.param.interval;
463
464 DBG_LOTS("* slots fans tick\n");
465
466 err = wf_sensor_get(slots_temp, &temp);
467 if (err) {
468 pr_warn("wf_rm31: slots temp sensor error %d\n", err);
469 failure_state |= FAILURE_SENSOR;
470 wf_control_set_max(slots_fan);
471 return;
472 }
473 speed = wf_pid_run(&slots_pid, temp);
474
475 DBG_LOTS("slots PID temp=%d.%.3d speed=%d\n",
476 FIX32TOPRINT(temp), speed);
477
478 slots_speed = speed;
479 err = wf_control_set(slots_fan, speed);
480 if (err) {
481 printk(KERN_WARNING "windfarm: slots bay fan error %d\n", err);
482 failure_state |= FAILURE_FAN;
483 }
484 }
485
slots_setup_pid(void)486 static void slots_setup_pid(void)
487 {
488 /* first time initialize things */
489 s32 fmin = wf_control_get_min(slots_fan);
490 s32 fmax = wf_control_get_max(slots_fan);
491 struct wf_pid_param param = slots_param;
492
493 param.min = max(param.min, fmin);
494 param.max = min(param.max, fmax);
495 wf_pid_init(&slots_pid, ¶m);
496 slots_tick = 1;
497
498 pr_info("wf_rm31: Slots control loop started.\n");
499 }
500
set_fail_state(void)501 static void set_fail_state(void)
502 {
503 cpu_max_all_fans();
504
505 if (backside_fan)
506 wf_control_set_max(backside_fan);
507 if (slots_fan)
508 wf_control_set_max(slots_fan);
509 }
510
rm31_tick(void)511 static void rm31_tick(void)
512 {
513 int i, last_failure;
514
515 if (!started) {
516 started = true;
517 printk(KERN_INFO "windfarm: CPUs control loops started.\n");
518 for (i = 0; i < nr_chips; ++i) {
519 if (cpu_setup_pid(i) < 0) {
520 failure_state = FAILURE_PERM;
521 set_fail_state();
522 break;
523 }
524 }
525 DBG_LOTS("cpu_all_tmax=%d.%03d\n", FIX32TOPRINT(cpu_all_tmax));
526
527 backside_setup_pid();
528 slots_setup_pid();
529
530 #ifdef HACKED_OVERTEMP
531 cpu_all_tmax = 60 << 16;
532 #endif
533 }
534
535 /* Permanent failure, bail out */
536 if (failure_state & FAILURE_PERM)
537 return;
538
539 /*
540 * Clear all failure bits except low overtemp which will be eventually
541 * cleared by the control loop itself
542 */
543 last_failure = failure_state;
544 failure_state &= FAILURE_LOW_OVERTEMP;
545 backside_fan_tick();
546 slots_fan_tick();
547
548 /* We do CPUs last because they can be clamped high by
549 * DIMM temperature
550 */
551 cpu_fans_tick();
552
553 DBG_LOTS(" last_failure: 0x%x, failure_state: %x\n",
554 last_failure, failure_state);
555
556 /* Check for failures. Any failure causes cpufreq clamping */
557 if (failure_state && last_failure == 0 && cpufreq_clamp)
558 wf_control_set_max(cpufreq_clamp);
559 if (failure_state == 0 && last_failure && cpufreq_clamp)
560 wf_control_set_min(cpufreq_clamp);
561
562 /* That's it for now, we might want to deal with other failures
563 * differently in the future though
564 */
565 }
566
rm31_new_control(struct wf_control * ct)567 static void rm31_new_control(struct wf_control *ct)
568 {
569 bool all_controls;
570
571 if (!strcmp(ct->name, "cpu-fan-a-0"))
572 cpu_fans[0][0] = ct;
573 else if (!strcmp(ct->name, "cpu-fan-b-0"))
574 cpu_fans[0][1] = ct;
575 else if (!strcmp(ct->name, "cpu-fan-c-0"))
576 cpu_fans[0][2] = ct;
577 else if (!strcmp(ct->name, "cpu-fan-a-1"))
578 cpu_fans[1][0] = ct;
579 else if (!strcmp(ct->name, "cpu-fan-b-1"))
580 cpu_fans[1][1] = ct;
581 else if (!strcmp(ct->name, "cpu-fan-c-1"))
582 cpu_fans[1][2] = ct;
583 else if (!strcmp(ct->name, "backside-fan"))
584 backside_fan = ct;
585 else if (!strcmp(ct->name, "slots-fan"))
586 slots_fan = ct;
587 else if (!strcmp(ct->name, "cpufreq-clamp"))
588 cpufreq_clamp = ct;
589
590 all_controls =
591 cpu_fans[0][0] &&
592 cpu_fans[0][1] &&
593 cpu_fans[0][2] &&
594 backside_fan &&
595 slots_fan;
596 if (nr_chips > 1)
597 all_controls &=
598 cpu_fans[1][0] &&
599 cpu_fans[1][1] &&
600 cpu_fans[1][2];
601 have_all_controls = all_controls;
602 }
603
604
rm31_new_sensor(struct wf_sensor * sr)605 static void rm31_new_sensor(struct wf_sensor *sr)
606 {
607 bool all_sensors;
608
609 if (!strcmp(sr->name, "cpu-diode-temp-0"))
610 sens_cpu_temp[0] = sr;
611 else if (!strcmp(sr->name, "cpu-diode-temp-1"))
612 sens_cpu_temp[1] = sr;
613 else if (!strcmp(sr->name, "cpu-voltage-0"))
614 sens_cpu_volts[0] = sr;
615 else if (!strcmp(sr->name, "cpu-voltage-1"))
616 sens_cpu_volts[1] = sr;
617 else if (!strcmp(sr->name, "cpu-current-0"))
618 sens_cpu_amps[0] = sr;
619 else if (!strcmp(sr->name, "cpu-current-1"))
620 sens_cpu_amps[1] = sr;
621 else if (!strcmp(sr->name, "backside-temp"))
622 backside_temp = sr;
623 else if (!strcmp(sr->name, "slots-temp"))
624 slots_temp = sr;
625 else if (!strcmp(sr->name, "dimms-temp"))
626 dimms_temp = sr;
627
628 all_sensors =
629 sens_cpu_temp[0] &&
630 sens_cpu_volts[0] &&
631 sens_cpu_amps[0] &&
632 backside_temp &&
633 slots_temp &&
634 dimms_temp;
635 if (nr_chips > 1)
636 all_sensors &=
637 sens_cpu_temp[1] &&
638 sens_cpu_volts[1] &&
639 sens_cpu_amps[1];
640
641 have_all_sensors = all_sensors;
642 }
643
rm31_wf_notify(struct notifier_block * self,unsigned long event,void * data)644 static int rm31_wf_notify(struct notifier_block *self,
645 unsigned long event, void *data)
646 {
647 switch (event) {
648 case WF_EVENT_NEW_SENSOR:
649 rm31_new_sensor(data);
650 break;
651 case WF_EVENT_NEW_CONTROL:
652 rm31_new_control(data);
653 break;
654 case WF_EVENT_TICK:
655 if (have_all_controls && have_all_sensors)
656 rm31_tick();
657 }
658 return 0;
659 }
660
661 static struct notifier_block rm31_events = {
662 .notifier_call = rm31_wf_notify,
663 };
664
wf_rm31_probe(struct platform_device * dev)665 static int wf_rm31_probe(struct platform_device *dev)
666 {
667 wf_register_client(&rm31_events);
668 return 0;
669 }
670
wf_rm31_remove(struct platform_device * dev)671 static int wf_rm31_remove(struct platform_device *dev)
672 {
673 wf_unregister_client(&rm31_events);
674
675 /* should release all sensors and controls */
676 return 0;
677 }
678
679 static struct platform_driver wf_rm31_driver = {
680 .probe = wf_rm31_probe,
681 .remove = wf_rm31_remove,
682 .driver = {
683 .name = "windfarm",
684 },
685 };
686
wf_rm31_init(void)687 static int __init wf_rm31_init(void)
688 {
689 struct device_node *cpu;
690 int i;
691
692 if (!of_machine_is_compatible("RackMac3,1"))
693 return -ENODEV;
694
695 /* Count the number of CPU cores */
696 nr_chips = 0;
697 for_each_node_by_type(cpu, "cpu")
698 ++nr_chips;
699 if (nr_chips > NR_CHIPS)
700 nr_chips = NR_CHIPS;
701
702 pr_info("windfarm: Initializing for desktop G5 with %d chips\n",
703 nr_chips);
704
705 /* Get MPU data for each CPU */
706 for (i = 0; i < nr_chips; i++) {
707 cpu_mpu_data[i] = wf_get_mpu(i);
708 if (!cpu_mpu_data[i]) {
709 pr_err("wf_rm31: Failed to find MPU data for CPU %d\n", i);
710 return -ENXIO;
711 }
712 }
713
714 #ifdef MODULE
715 request_module("windfarm_fcu_controls");
716 request_module("windfarm_lm75_sensor");
717 request_module("windfarm_lm87_sensor");
718 request_module("windfarm_ad7417_sensor");
719 request_module("windfarm_max6690_sensor");
720 request_module("windfarm_cpufreq_clamp");
721 #endif /* MODULE */
722
723 platform_driver_register(&wf_rm31_driver);
724 return 0;
725 }
726
wf_rm31_exit(void)727 static void __exit wf_rm31_exit(void)
728 {
729 platform_driver_unregister(&wf_rm31_driver);
730 }
731
732 module_init(wf_rm31_init);
733 module_exit(wf_rm31_exit);
734
735 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
736 MODULE_DESCRIPTION("Thermal control for Xserve G5");
737 MODULE_LICENSE("GPL");
738 MODULE_ALIAS("platform:windfarm");
739