1/*
2 * Windfarm PowerMac thermal control.
3 * Control loops for machines with SMU and PPC970MP processors.
4 *
5 * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
6 * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
7 *
8 * Use and redistribute under the terms of the GNU GPL v2.
9 */
10#include <linux/types.h>
11#include <linux/errno.h>
12#include <linux/kernel.h>
13#include <linux/device.h>
14#include <linux/platform_device.h>
15#include <linux/reboot.h>
16#include <asm/prom.h>
17#include <asm/smu.h>
18
19#include "windfarm.h"
20#include "windfarm_pid.h"
21
22#define VERSION "0.2"
23
24#define DEBUG
25#undef LOTSA_DEBUG
26
27#ifdef DEBUG
28#define DBG(args...)	printk(args)
29#else
30#define DBG(args...)	do { } while(0)
31#endif
32
33#ifdef LOTSA_DEBUG
34#define DBG_LOTS(args...)	printk(args)
35#else
36#define DBG_LOTS(args...)	do { } while(0)
37#endif
38
39/* define this to force CPU overtemp to 60 degree, useful for testing
40 * the overtemp code
41 */
42#undef HACKED_OVERTEMP
43
44/* We currently only handle 2 chips, 4 cores... */
45#define NR_CHIPS	2
46#define NR_CORES	4
47#define NR_CPU_FANS	3 * NR_CHIPS
48
49/* Controls and sensors */
50static struct wf_sensor *sens_cpu_temp[NR_CORES];
51static struct wf_sensor *sens_cpu_power[NR_CORES];
52static struct wf_sensor *hd_temp;
53static struct wf_sensor *slots_power;
54static struct wf_sensor *u4_temp;
55
56static struct wf_control *cpu_fans[NR_CPU_FANS];
57static char *cpu_fan_names[NR_CPU_FANS] = {
58	"cpu-rear-fan-0",
59	"cpu-rear-fan-1",
60	"cpu-front-fan-0",
61	"cpu-front-fan-1",
62	"cpu-pump-0",
63	"cpu-pump-1",
64};
65static struct wf_control *cpufreq_clamp;
66
67/* Second pump isn't required (and isn't actually present) */
68#define CPU_FANS_REQD		(NR_CPU_FANS - 2)
69#define FIRST_PUMP		4
70#define LAST_PUMP		5
71
72/* We keep a temperature history for average calculation of 180s */
73#define CPU_TEMP_HIST_SIZE	180
74
75/* Scale factor for fan speed, *100 */
76static int cpu_fan_scale[NR_CPU_FANS] = {
77	100,
78	100,
79	97,		/* inlet fans run at 97% of exhaust fan */
80	97,
81	100,		/* updated later */
82	100,		/* updated later */
83};
84
85static struct wf_control *backside_fan;
86static struct wf_control *slots_fan;
87static struct wf_control *drive_bay_fan;
88
89/* PID loop state */
90static struct wf_cpu_pid_state cpu_pid[NR_CORES];
91static u32 cpu_thist[CPU_TEMP_HIST_SIZE];
92static int cpu_thist_pt;
93static s64 cpu_thist_total;
94static s32 cpu_all_tmax = 100 << 16;
95static int cpu_last_target;
96static struct wf_pid_state backside_pid;
97static int backside_tick;
98static struct wf_pid_state slots_pid;
99static int slots_started;
100static struct wf_pid_state drive_bay_pid;
101static int drive_bay_tick;
102
103static int nr_cores;
104static int have_all_controls;
105static int have_all_sensors;
106static int started;
107
108static int failure_state;
109#define FAILURE_SENSOR		1
110#define FAILURE_FAN		2
111#define FAILURE_PERM		4
112#define FAILURE_LOW_OVERTEMP	8
113#define FAILURE_HIGH_OVERTEMP	16
114
115/* Overtemp values */
116#define LOW_OVER_AVERAGE	0
117#define LOW_OVER_IMMEDIATE	(10 << 16)
118#define LOW_OVER_CLEAR		((-10) << 16)
119#define HIGH_OVER_IMMEDIATE	(14 << 16)
120#define HIGH_OVER_AVERAGE	(10 << 16)
121#define HIGH_OVER_IMMEDIATE	(14 << 16)
122
123
124/* Implementation... */
125static int create_cpu_loop(int cpu)
126{
127	int chip = cpu / 2;
128	int core = cpu & 1;
129	struct smu_sdbp_header *hdr;
130	struct smu_sdbp_cpupiddata *piddata;
131	struct wf_cpu_pid_param pid;
132	struct wf_control *main_fan = cpu_fans[0];
133	s32 tmax;
134	int fmin;
135
136	/* Get PID params from the appropriate SAT */
137	hdr = smu_sat_get_sdb_partition(chip, 0xC8 + core, NULL);
138	if (hdr == NULL) {
139		printk(KERN_WARNING"windfarm: can't get CPU PID fan config\n");
140		return -EINVAL;
141	}
142	piddata = (struct smu_sdbp_cpupiddata *)&hdr[1];
143
144	/* Get FVT params to get Tmax; if not found, assume default */
145	hdr = smu_sat_get_sdb_partition(chip, 0xC4 + core, NULL);
146	if (hdr) {
147		struct smu_sdbp_fvt *fvt = (struct smu_sdbp_fvt *)&hdr[1];
148		tmax = fvt->maxtemp << 16;
149	} else
150		tmax = 95 << 16;	/* default to 95 degrees C */
151
152	/* We keep a global tmax for overtemp calculations */
153	if (tmax < cpu_all_tmax)
154		cpu_all_tmax = tmax;
155
156	/*
157	 * Darwin has a minimum fan speed of 1000 rpm for the 4-way and
158	 * 515 for the 2-way.  That appears to be overkill, so for now,
159	 * impose a minimum of 750 or 515.
160	 */
161	fmin = (nr_cores > 2) ? 750 : 515;
162
163	/* Initialize PID loop */
164	pid.interval = 1;	/* seconds */
165	pid.history_len = piddata->history_len;
166	pid.gd = piddata->gd;
167	pid.gp = piddata->gp;
168	pid.gr = piddata->gr / piddata->history_len;
169	pid.pmaxadj = (piddata->max_power << 16) - (piddata->power_adj << 8);
170	pid.ttarget = tmax - (piddata->target_temp_delta << 16);
171	pid.tmax = tmax;
172	pid.min = main_fan->ops->get_min(main_fan);
173	pid.max = main_fan->ops->get_max(main_fan);
174	if (pid.min < fmin)
175		pid.min = fmin;
176
177	wf_cpu_pid_init(&cpu_pid[cpu], &pid);
178	return 0;
179}
180
181static void cpu_max_all_fans(void)
182{
183	int i;
184
185	/* We max all CPU fans in case of a sensor error. We also do the
186	 * cpufreq clamping now, even if it's supposedly done later by the
187	 * generic code anyway, we do it earlier here to react faster
188	 */
189	if (cpufreq_clamp)
190		wf_control_set_max(cpufreq_clamp);
191	for (i = 0; i < NR_CPU_FANS; ++i)
192		if (cpu_fans[i])
193			wf_control_set_max(cpu_fans[i]);
194}
195
196static int cpu_check_overtemp(s32 temp)
197{
198	int new_state = 0;
199	s32 t_avg, t_old;
200
201	/* First check for immediate overtemps */
202	if (temp >= (cpu_all_tmax + LOW_OVER_IMMEDIATE)) {
203		new_state |= FAILURE_LOW_OVERTEMP;
204		if ((failure_state & FAILURE_LOW_OVERTEMP) == 0)
205			printk(KERN_ERR "windfarm: Overtemp due to immediate CPU"
206			       " temperature !\n");
207	}
208	if (temp >= (cpu_all_tmax + HIGH_OVER_IMMEDIATE)) {
209		new_state |= FAILURE_HIGH_OVERTEMP;
210		if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0)
211			printk(KERN_ERR "windfarm: Critical overtemp due to"
212			       " immediate CPU temperature !\n");
213	}
214
215	/* We calculate a history of max temperatures and use that for the
216	 * overtemp management
217	 */
218	t_old = cpu_thist[cpu_thist_pt];
219	cpu_thist[cpu_thist_pt] = temp;
220	cpu_thist_pt = (cpu_thist_pt + 1) % CPU_TEMP_HIST_SIZE;
221	cpu_thist_total -= t_old;
222	cpu_thist_total += temp;
223	t_avg = cpu_thist_total / CPU_TEMP_HIST_SIZE;
224
225	DBG_LOTS("t_avg = %d.%03d (out: %d.%03d, in: %d.%03d)\n",
226		 FIX32TOPRINT(t_avg), FIX32TOPRINT(t_old), FIX32TOPRINT(temp));
227
228	/* Now check for average overtemps */
229	if (t_avg >= (cpu_all_tmax + LOW_OVER_AVERAGE)) {
230		new_state |= FAILURE_LOW_OVERTEMP;
231		if ((failure_state & FAILURE_LOW_OVERTEMP) == 0)
232			printk(KERN_ERR "windfarm: Overtemp due to average CPU"
233			       " temperature !\n");
234	}
235	if (t_avg >= (cpu_all_tmax + HIGH_OVER_AVERAGE)) {
236		new_state |= FAILURE_HIGH_OVERTEMP;
237		if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0)
238			printk(KERN_ERR "windfarm: Critical overtemp due to"
239			       " average CPU temperature !\n");
240	}
241
242	/* Now handle overtemp conditions. We don't currently use the windfarm
243	 * overtemp handling core as it's not fully suited to the needs of those
244	 * new machine. This will be fixed later.
245	 */
246	if (new_state) {
247		/* High overtemp -> immediate shutdown */
248		if (new_state & FAILURE_HIGH_OVERTEMP)
249			machine_power_off();
250		if ((failure_state & new_state) != new_state)
251			cpu_max_all_fans();
252		failure_state |= new_state;
253	} else if ((failure_state & FAILURE_LOW_OVERTEMP) &&
254		   (temp < (cpu_all_tmax + LOW_OVER_CLEAR))) {
255		printk(KERN_ERR "windfarm: Overtemp condition cleared !\n");
256		failure_state &= ~FAILURE_LOW_OVERTEMP;
257	}
258
259	return failure_state & (FAILURE_LOW_OVERTEMP | FAILURE_HIGH_OVERTEMP);
260}
261
262static void cpu_fans_tick(void)
263{
264	int err, cpu;
265	s32 greatest_delta = 0;
266	s32 temp, power, t_max = 0;
267	int i, t, target = 0;
268	struct wf_sensor *sr;
269	struct wf_control *ct;
270	struct wf_cpu_pid_state *sp;
271
272	DBG_LOTS(KERN_DEBUG);
273	for (cpu = 0; cpu < nr_cores; ++cpu) {
274		/* Get CPU core temperature */
275		sr = sens_cpu_temp[cpu];
276		err = sr->ops->get_value(sr, &temp);
277		if (err) {
278			DBG("\n");
279			printk(KERN_WARNING "windfarm: CPU %d temperature "
280			       "sensor error %d\n", cpu, err);
281			failure_state |= FAILURE_SENSOR;
282			cpu_max_all_fans();
283			return;
284		}
285
286		/* Keep track of highest temp */
287		t_max = max(t_max, temp);
288
289		/* Get CPU power */
290		sr = sens_cpu_power[cpu];
291		err = sr->ops->get_value(sr, &power);
292		if (err) {
293			DBG("\n");
294			printk(KERN_WARNING "windfarm: CPU %d power "
295			       "sensor error %d\n", cpu, err);
296			failure_state |= FAILURE_SENSOR;
297			cpu_max_all_fans();
298			return;
299		}
300
301		/* Run PID */
302		sp = &cpu_pid[cpu];
303		t = wf_cpu_pid_run(sp, power, temp);
304
305		if (cpu == 0 || sp->last_delta > greatest_delta) {
306			greatest_delta = sp->last_delta;
307			target = t;
308		}
309		DBG_LOTS("[%d] P=%d.%.3d T=%d.%.3d ",
310		    cpu, FIX32TOPRINT(power), FIX32TOPRINT(temp));
311	}
312	DBG_LOTS("fans = %d, t_max = %d.%03d\n", target, FIX32TOPRINT(t_max));
313
314	/* Darwin limits decrease to 20 per iteration */
315	if (target < (cpu_last_target - 20))
316		target = cpu_last_target - 20;
317	cpu_last_target = target;
318	for (cpu = 0; cpu < nr_cores; ++cpu)
319		cpu_pid[cpu].target = target;
320
321	/* Handle possible overtemps */
322	if (cpu_check_overtemp(t_max))
323		return;
324
325	/* Set fans */
326	for (i = 0; i < NR_CPU_FANS; ++i) {
327		ct = cpu_fans[i];
328		if (ct == NULL)
329			continue;
330		err = ct->ops->set_value(ct, target * cpu_fan_scale[i] / 100);
331		if (err) {
332			printk(KERN_WARNING "windfarm: fan %s reports "
333			       "error %d\n", ct->name, err);
334			failure_state |= FAILURE_FAN;
335			break;
336		}
337	}
338}
339
340/* Backside/U4 fan */
341static struct wf_pid_param backside_param = {
342	.interval	= 5,
343	.history_len	= 2,
344	.gd		= 48 << 20,
345	.gp		= 5 << 20,
346	.gr		= 0,
347	.itarget	= 64 << 16,
348	.additive	= 1,
349};
350
351static void backside_fan_tick(void)
352{
353	s32 temp;
354	int speed;
355	int err;
356
357	if (!backside_fan || !u4_temp)
358		return;
359	if (!backside_tick) {
360		/* first time; initialize things */
361		printk(KERN_INFO "windfarm: Backside control loop started.\n");
362		backside_param.min = backside_fan->ops->get_min(backside_fan);
363		backside_param.max = backside_fan->ops->get_max(backside_fan);
364		wf_pid_init(&backside_pid, &backside_param);
365		backside_tick = 1;
366	}
367	if (--backside_tick > 0)
368		return;
369	backside_tick = backside_pid.param.interval;
370
371	err = u4_temp->ops->get_value(u4_temp, &temp);
372	if (err) {
373		printk(KERN_WARNING "windfarm: U4 temp sensor error %d\n",
374		       err);
375		failure_state |= FAILURE_SENSOR;
376		wf_control_set_max(backside_fan);
377		return;
378	}
379	speed = wf_pid_run(&backside_pid, temp);
380	DBG_LOTS("backside PID temp=%d.%.3d speed=%d\n",
381		 FIX32TOPRINT(temp), speed);
382
383	err = backside_fan->ops->set_value(backside_fan, speed);
384	if (err) {
385		printk(KERN_WARNING "windfarm: backside fan error %d\n", err);
386		failure_state |= FAILURE_FAN;
387	}
388}
389
390/* Drive bay fan */
391static struct wf_pid_param drive_bay_prm = {
392	.interval	= 5,
393	.history_len	= 2,
394	.gd		= 30 << 20,
395	.gp		= 5 << 20,
396	.gr		= 0,
397	.itarget	= 40 << 16,
398	.additive	= 1,
399};
400
401static void drive_bay_fan_tick(void)
402{
403	s32 temp;
404	int speed;
405	int err;
406
407	if (!drive_bay_fan || !hd_temp)
408		return;
409	if (!drive_bay_tick) {
410		/* first time; initialize things */
411		printk(KERN_INFO "windfarm: Drive bay control loop started.\n");
412		drive_bay_prm.min = drive_bay_fan->ops->get_min(drive_bay_fan);
413		drive_bay_prm.max = drive_bay_fan->ops->get_max(drive_bay_fan);
414		wf_pid_init(&drive_bay_pid, &drive_bay_prm);
415		drive_bay_tick = 1;
416	}
417	if (--drive_bay_tick > 0)
418		return;
419	drive_bay_tick = drive_bay_pid.param.interval;
420
421	err = hd_temp->ops->get_value(hd_temp, &temp);
422	if (err) {
423		printk(KERN_WARNING "windfarm: drive bay temp sensor "
424		       "error %d\n", err);
425		failure_state |= FAILURE_SENSOR;
426		wf_control_set_max(drive_bay_fan);
427		return;
428	}
429	speed = wf_pid_run(&drive_bay_pid, temp);
430	DBG_LOTS("drive_bay PID temp=%d.%.3d speed=%d\n",
431		 FIX32TOPRINT(temp), speed);
432
433	err = drive_bay_fan->ops->set_value(drive_bay_fan, speed);
434	if (err) {
435		printk(KERN_WARNING "windfarm: drive bay fan error %d\n", err);
436		failure_state |= FAILURE_FAN;
437	}
438}
439
440/* PCI slots area fan */
441/* This makes the fan speed proportional to the power consumed */
442static struct wf_pid_param slots_param = {
443	.interval	= 1,
444	.history_len	= 2,
445	.gd		= 0,
446	.gp		= 0,
447	.gr		= 0x1277952,
448	.itarget	= 0,
449	.min		= 1560,
450	.max		= 3510,
451};
452
453static void slots_fan_tick(void)
454{
455	s32 power;
456	int speed;
457	int err;
458
459	if (!slots_fan || !slots_power)
460		return;
461	if (!slots_started) {
462		/* first time; initialize things */
463		printk(KERN_INFO "windfarm: Slots control loop started.\n");
464		wf_pid_init(&slots_pid, &slots_param);
465		slots_started = 1;
466	}
467
468	err = slots_power->ops->get_value(slots_power, &power);
469	if (err) {
470		printk(KERN_WARNING "windfarm: slots power sensor error %d\n",
471		       err);
472		failure_state |= FAILURE_SENSOR;
473		wf_control_set_max(slots_fan);
474		return;
475	}
476	speed = wf_pid_run(&slots_pid, power);
477	DBG_LOTS("slots PID power=%d.%.3d speed=%d\n",
478		 FIX32TOPRINT(power), speed);
479
480	err = slots_fan->ops->set_value(slots_fan, speed);
481	if (err) {
482		printk(KERN_WARNING "windfarm: slots fan error %d\n", err);
483		failure_state |= FAILURE_FAN;
484	}
485}
486
487static void set_fail_state(void)
488{
489	int i;
490
491	if (cpufreq_clamp)
492		wf_control_set_max(cpufreq_clamp);
493	for (i = 0; i < NR_CPU_FANS; ++i)
494		if (cpu_fans[i])
495			wf_control_set_max(cpu_fans[i]);
496	if (backside_fan)
497		wf_control_set_max(backside_fan);
498	if (slots_fan)
499		wf_control_set_max(slots_fan);
500	if (drive_bay_fan)
501		wf_control_set_max(drive_bay_fan);
502}
503
504static void pm112_tick(void)
505{
506	int i, last_failure;
507
508	if (!started) {
509		started = 1;
510		printk(KERN_INFO "windfarm: CPUs control loops started.\n");
511		for (i = 0; i < nr_cores; ++i) {
512			if (create_cpu_loop(i) < 0) {
513				failure_state = FAILURE_PERM;
514				set_fail_state();
515				break;
516			}
517		}
518		DBG_LOTS("cpu_all_tmax=%d.%03d\n", FIX32TOPRINT(cpu_all_tmax));
519
520#ifdef HACKED_OVERTEMP
521		cpu_all_tmax = 60 << 16;
522#endif
523	}
524
525	/* Permanent failure, bail out */
526	if (failure_state & FAILURE_PERM)
527		return;
528	/* Clear all failure bits except low overtemp which will be eventually
529	 * cleared by the control loop itself
530	 */
531	last_failure = failure_state;
532	failure_state &= FAILURE_LOW_OVERTEMP;
533	cpu_fans_tick();
534	backside_fan_tick();
535	slots_fan_tick();
536	drive_bay_fan_tick();
537
538	DBG_LOTS("last_failure: 0x%x, failure_state: %x\n",
539		 last_failure, failure_state);
540
541	/* Check for failures. Any failure causes cpufreq clamping */
542	if (failure_state && last_failure == 0 && cpufreq_clamp)
543		wf_control_set_max(cpufreq_clamp);
544	if (failure_state == 0 && last_failure && cpufreq_clamp)
545		wf_control_set_min(cpufreq_clamp);
546
547	/* That's it for now, we might want to deal with other failures
548	 * differently in the future though
549	 */
550}
551
552static void pm112_new_control(struct wf_control *ct)
553{
554	int i, max_exhaust;
555
556	if (cpufreq_clamp == NULL && !strcmp(ct->name, "cpufreq-clamp")) {
557		if (wf_get_control(ct) == 0)
558			cpufreq_clamp = ct;
559	}
560
561	for (i = 0; i < NR_CPU_FANS; ++i) {
562		if (!strcmp(ct->name, cpu_fan_names[i])) {
563			if (cpu_fans[i] == NULL && wf_get_control(ct) == 0)
564				cpu_fans[i] = ct;
565			break;
566		}
567	}
568	if (i >= NR_CPU_FANS) {
569		/* not a CPU fan, try the others */
570		if (!strcmp(ct->name, "backside-fan")) {
571			if (backside_fan == NULL && wf_get_control(ct) == 0)
572				backside_fan = ct;
573		} else if (!strcmp(ct->name, "slots-fan")) {
574			if (slots_fan == NULL && wf_get_control(ct) == 0)
575				slots_fan = ct;
576		} else if (!strcmp(ct->name, "drive-bay-fan")) {
577			if (drive_bay_fan == NULL && wf_get_control(ct) == 0)
578				drive_bay_fan = ct;
579		}
580		return;
581	}
582
583	for (i = 0; i < CPU_FANS_REQD; ++i)
584		if (cpu_fans[i] == NULL)
585			return;
586
587	/* work out pump scaling factors */
588	max_exhaust = cpu_fans[0]->ops->get_max(cpu_fans[0]);
589	for (i = FIRST_PUMP; i <= LAST_PUMP; ++i)
590		if ((ct = cpu_fans[i]) != NULL)
591			cpu_fan_scale[i] =
592				ct->ops->get_max(ct) * 100 / max_exhaust;
593
594	have_all_controls = 1;
595}
596
597static void pm112_new_sensor(struct wf_sensor *sr)
598{
599	unsigned int i;
600
601	if (!strncmp(sr->name, "cpu-temp-", 9)) {
602		i = sr->name[9] - '0';
603		if (sr->name[10] == 0 && i < NR_CORES &&
604		    sens_cpu_temp[i] == NULL && wf_get_sensor(sr) == 0)
605			sens_cpu_temp[i] = sr;
606
607	} else if (!strncmp(sr->name, "cpu-power-", 10)) {
608		i = sr->name[10] - '0';
609		if (sr->name[11] == 0 && i < NR_CORES &&
610		    sens_cpu_power[i] == NULL && wf_get_sensor(sr) == 0)
611			sens_cpu_power[i] = sr;
612	} else if (!strcmp(sr->name, "hd-temp")) {
613		if (hd_temp == NULL && wf_get_sensor(sr) == 0)
614			hd_temp = sr;
615	} else if (!strcmp(sr->name, "slots-power")) {
616		if (slots_power == NULL && wf_get_sensor(sr) == 0)
617			slots_power = sr;
618	} else if (!strcmp(sr->name, "backside-temp")) {
619		if (u4_temp == NULL && wf_get_sensor(sr) == 0)
620			u4_temp = sr;
621	} else
622		return;
623
624	/* check if we have all the sensors we need */
625	for (i = 0; i < nr_cores; ++i)
626		if (sens_cpu_temp[i] == NULL || sens_cpu_power[i] == NULL)
627			return;
628
629	have_all_sensors = 1;
630}
631
632static int pm112_wf_notify(struct notifier_block *self,
633			   unsigned long event, void *data)
634{
635	switch (event) {
636	case WF_EVENT_NEW_SENSOR:
637		pm112_new_sensor(data);
638		break;
639	case WF_EVENT_NEW_CONTROL:
640		pm112_new_control(data);
641		break;
642	case WF_EVENT_TICK:
643		if (have_all_controls && have_all_sensors)
644			pm112_tick();
645	}
646	return 0;
647}
648
649static struct notifier_block pm112_events = {
650	.notifier_call = pm112_wf_notify,
651};
652
653static int wf_pm112_probe(struct platform_device *dev)
654{
655	wf_register_client(&pm112_events);
656	return 0;
657}
658
659static int wf_pm112_remove(struct platform_device *dev)
660{
661	wf_unregister_client(&pm112_events);
662	/* should release all sensors and controls */
663	return 0;
664}
665
666static struct platform_driver wf_pm112_driver = {
667	.probe = wf_pm112_probe,
668	.remove = wf_pm112_remove,
669	.driver = {
670		.name = "windfarm",
671		.owner	= THIS_MODULE,
672	},
673};
674
675static int __init wf_pm112_init(void)
676{
677	struct device_node *cpu;
678
679	if (!of_machine_is_compatible("PowerMac11,2"))
680		return -ENODEV;
681
682	/* Count the number of CPU cores */
683	nr_cores = 0;
684	for_each_node_by_type(cpu, "cpu")
685		++nr_cores;
686
687	printk(KERN_INFO "windfarm: initializing for dual-core desktop G5\n");
688
689#ifdef MODULE
690	request_module("windfarm_smu_controls");
691	request_module("windfarm_smu_sensors");
692	request_module("windfarm_smu_sat");
693	request_module("windfarm_lm75_sensor");
694	request_module("windfarm_max6690_sensor");
695	request_module("windfarm_cpufreq_clamp");
696
697#endif /* MODULE */
698
699	platform_driver_register(&wf_pm112_driver);
700	return 0;
701}
702
703static void __exit wf_pm112_exit(void)
704{
705	platform_driver_unregister(&wf_pm112_driver);
706}
707
708module_init(wf_pm112_init);
709module_exit(wf_pm112_exit);
710
711MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
712MODULE_DESCRIPTION("Thermal control for PowerMac11,2");
713MODULE_LICENSE("GPL");
714MODULE_ALIAS("platform:windfarm");
715