1 /*
2  * Windfarm PowerMac thermal control.
3  * Control loops for PowerMac7,2 and 7,3
4  *
5  * Copyright (C) 2012 Benjamin Herrenschmidt, IBM Corp.
6  *
7  * Use and redistribute under the terms of the GNU GPL v2.
8  */
9 #include <linux/types.h>
10 #include <linux/errno.h>
11 #include <linux/kernel.h>
12 #include <linux/device.h>
13 #include <linux/platform_device.h>
14 #include <linux/reboot.h>
15 #include <asm/prom.h>
16 #include <asm/smu.h>
17 
18 #include "windfarm.h"
19 #include "windfarm_pid.h"
20 #include "windfarm_mpu.h"
21 
22 #define VERSION "1.0"
23 
24 #undef 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 */
45 #define NR_CHIPS	2
46 #define NR_CPU_FANS	3 * NR_CHIPS
47 
48 /* Controls and sensors */
49 static struct wf_sensor *sens_cpu_temp[NR_CHIPS];
50 static struct wf_sensor *sens_cpu_volts[NR_CHIPS];
51 static struct wf_sensor *sens_cpu_amps[NR_CHIPS];
52 static struct wf_sensor *backside_temp;
53 static struct wf_sensor *drives_temp;
54 
55 static struct wf_control *cpu_front_fans[NR_CHIPS];
56 static struct wf_control *cpu_rear_fans[NR_CHIPS];
57 static struct wf_control *cpu_pumps[NR_CHIPS];
58 static struct wf_control *backside_fan;
59 static struct wf_control *drives_fan;
60 static struct wf_control *slots_fan;
61 static struct wf_control *cpufreq_clamp;
62 
63 /* We keep a temperature history for average calculation of 180s */
64 #define CPU_TEMP_HIST_SIZE	180
65 
66 /* Fixed speed for slot fan */
67 #define	SLOTS_FAN_DEFAULT_PWM	40
68 
69 /* Scale value for CPU intake fans */
70 #define CPU_INTAKE_SCALE	0x0000f852
71 
72 /* PID loop state */
73 static const struct mpu_data *cpu_mpu_data[NR_CHIPS];
74 static struct wf_cpu_pid_state cpu_pid[NR_CHIPS];
75 static bool cpu_pid_combined;
76 static u32 cpu_thist[CPU_TEMP_HIST_SIZE];
77 static int cpu_thist_pt;
78 static s64 cpu_thist_total;
79 static s32 cpu_all_tmax = 100 << 16;
80 static struct wf_pid_state backside_pid;
81 static int backside_tick;
82 static struct wf_pid_state drives_pid;
83 static int drives_tick;
84 
85 static int nr_chips;
86 static bool have_all_controls;
87 static bool have_all_sensors;
88 static bool started;
89 
90 static int failure_state;
91 #define FAILURE_SENSOR		1
92 #define FAILURE_FAN		2
93 #define FAILURE_PERM		4
94 #define FAILURE_LOW_OVERTEMP	8
95 #define FAILURE_HIGH_OVERTEMP	16
96 
97 /* Overtemp values */
98 #define LOW_OVER_AVERAGE	0
99 #define LOW_OVER_IMMEDIATE	(10 << 16)
100 #define LOW_OVER_CLEAR		((-10) << 16)
101 #define HIGH_OVER_IMMEDIATE	(14 << 16)
102 #define HIGH_OVER_AVERAGE	(10 << 16)
103 #define HIGH_OVER_IMMEDIATE	(14 << 16)
104 
105 
106 static void cpu_max_all_fans(void)
107 {
108 	int i;
109 
110 	/* We max all CPU fans in case of a sensor error. We also do the
111 	 * cpufreq clamping now, even if it's supposedly done later by the
112 	 * generic code anyway, we do it earlier here to react faster
113 	 */
114 	if (cpufreq_clamp)
115 		wf_control_set_max(cpufreq_clamp);
116 	for (i = 0; i < nr_chips; i++) {
117 		if (cpu_front_fans[i])
118 			wf_control_set_max(cpu_front_fans[i]);
119 		if (cpu_rear_fans[i])
120 			wf_control_set_max(cpu_rear_fans[i]);
121 		if (cpu_pumps[i])
122 			wf_control_set_max(cpu_pumps[i]);
123 	}
124 }
125 
126 static int cpu_check_overtemp(s32 temp)
127 {
128 	int new_state = 0;
129 	s32 t_avg, t_old;
130 	static bool first = true;
131 
132 	/* First check for immediate overtemps */
133 	if (temp >= (cpu_all_tmax + LOW_OVER_IMMEDIATE)) {
134 		new_state |= FAILURE_LOW_OVERTEMP;
135 		if ((failure_state & FAILURE_LOW_OVERTEMP) == 0)
136 			printk(KERN_ERR "windfarm: Overtemp due to immediate CPU"
137 			       " temperature !\n");
138 	}
139 	if (temp >= (cpu_all_tmax + HIGH_OVER_IMMEDIATE)) {
140 		new_state |= FAILURE_HIGH_OVERTEMP;
141 		if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0)
142 			printk(KERN_ERR "windfarm: Critical overtemp due to"
143 			       " immediate CPU temperature !\n");
144 	}
145 
146 	/*
147 	 * The first time around, initialize the array with the first
148 	 * temperature reading
149 	 */
150 	if (first) {
151 		int i;
152 
153 		cpu_thist_total = 0;
154 		for (i = 0; i < CPU_TEMP_HIST_SIZE; i++) {
155 			cpu_thist[i] = temp;
156 			cpu_thist_total += temp;
157 		}
158 		first = false;
159 	}
160 
161 	/*
162 	 * We calculate a history of max temperatures and use that for the
163 	 * overtemp management
164 	 */
165 	t_old = cpu_thist[cpu_thist_pt];
166 	cpu_thist[cpu_thist_pt] = temp;
167 	cpu_thist_pt = (cpu_thist_pt + 1) % CPU_TEMP_HIST_SIZE;
168 	cpu_thist_total -= t_old;
169 	cpu_thist_total += temp;
170 	t_avg = cpu_thist_total / CPU_TEMP_HIST_SIZE;
171 
172 	DBG_LOTS("  t_avg = %d.%03d (out: %d.%03d, in: %d.%03d)\n",
173 		 FIX32TOPRINT(t_avg), FIX32TOPRINT(t_old), FIX32TOPRINT(temp));
174 
175 	/* Now check for average overtemps */
176 	if (t_avg >= (cpu_all_tmax + LOW_OVER_AVERAGE)) {
177 		new_state |= FAILURE_LOW_OVERTEMP;
178 		if ((failure_state & FAILURE_LOW_OVERTEMP) == 0)
179 			printk(KERN_ERR "windfarm: Overtemp due to average CPU"
180 			       " temperature !\n");
181 	}
182 	if (t_avg >= (cpu_all_tmax + HIGH_OVER_AVERAGE)) {
183 		new_state |= FAILURE_HIGH_OVERTEMP;
184 		if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0)
185 			printk(KERN_ERR "windfarm: Critical overtemp due to"
186 			       " average CPU temperature !\n");
187 	}
188 
189 	/* Now handle overtemp conditions. We don't currently use the windfarm
190 	 * overtemp handling core as it's not fully suited to the needs of those
191 	 * new machine. This will be fixed later.
192 	 */
193 	if (new_state) {
194 		/* High overtemp -> immediate shutdown */
195 		if (new_state & FAILURE_HIGH_OVERTEMP)
196 			machine_power_off();
197 		if ((failure_state & new_state) != new_state)
198 			cpu_max_all_fans();
199 		failure_state |= new_state;
200 	} else if ((failure_state & FAILURE_LOW_OVERTEMP) &&
201 		   (temp < (cpu_all_tmax + LOW_OVER_CLEAR))) {
202 		printk(KERN_ERR "windfarm: Overtemp condition cleared !\n");
203 		failure_state &= ~FAILURE_LOW_OVERTEMP;
204 	}
205 
206 	return failure_state & (FAILURE_LOW_OVERTEMP | FAILURE_HIGH_OVERTEMP);
207 }
208 
209 static int read_one_cpu_vals(int cpu, s32 *temp, s32 *power)
210 {
211 	s32 dtemp, volts, amps;
212 	int rc;
213 
214 	/* Get diode temperature */
215 	rc = wf_sensor_get(sens_cpu_temp[cpu], &dtemp);
216 	if (rc) {
217 		DBG("  CPU%d: temp reading error !\n", cpu);
218 		return -EIO;
219 	}
220 	DBG_LOTS("  CPU%d: temp   = %d.%03d\n", cpu, FIX32TOPRINT((dtemp)));
221 	*temp = dtemp;
222 
223 	/* Get voltage */
224 	rc = wf_sensor_get(sens_cpu_volts[cpu], &volts);
225 	if (rc) {
226 		DBG("  CPU%d, volts reading error !\n", cpu);
227 		return -EIO;
228 	}
229 	DBG_LOTS("  CPU%d: volts  = %d.%03d\n", cpu, FIX32TOPRINT((volts)));
230 
231 	/* Get current */
232 	rc = wf_sensor_get(sens_cpu_amps[cpu], &amps);
233 	if (rc) {
234 		DBG("  CPU%d, current reading error !\n", cpu);
235 		return -EIO;
236 	}
237 	DBG_LOTS("  CPU%d: amps   = %d.%03d\n", cpu, FIX32TOPRINT((amps)));
238 
239 	/* Calculate power */
240 
241 	/* Scale voltage and current raw sensor values according to fixed scales
242 	 * obtained in Darwin and calculate power from I and V
243 	 */
244 	*power = (((u64)volts) * ((u64)amps)) >> 16;
245 
246 	DBG_LOTS("  CPU%d: power  = %d.%03d\n", cpu, FIX32TOPRINT((*power)));
247 
248 	return 0;
249 
250 }
251 
252 static void cpu_fans_tick_split(void)
253 {
254 	int err, cpu;
255 	s32 intake, temp, power, t_max = 0;
256 
257 	DBG_LOTS("* cpu fans_tick_split()\n");
258 
259 	for (cpu = 0; cpu < nr_chips; ++cpu) {
260 		struct wf_cpu_pid_state *sp = &cpu_pid[cpu];
261 
262 		/* Read current speed */
263 		wf_control_get(cpu_rear_fans[cpu], &sp->target);
264 
265 		DBG_LOTS("  CPU%d: cur_target = %d RPM\n", cpu, sp->target);
266 
267 		err = read_one_cpu_vals(cpu, &temp, &power);
268 		if (err) {
269 			failure_state |= FAILURE_SENSOR;
270 			cpu_max_all_fans();
271 			return;
272 		}
273 
274 		/* Keep track of highest temp */
275 		t_max = max(t_max, temp);
276 
277 		/* Handle possible overtemps */
278 		if (cpu_check_overtemp(t_max))
279 			return;
280 
281 		/* Run PID */
282 		wf_cpu_pid_run(sp, power, temp);
283 
284 		DBG_LOTS("  CPU%d: target = %d RPM\n", cpu, sp->target);
285 
286 		/* Apply result directly to exhaust fan */
287 		err = wf_control_set(cpu_rear_fans[cpu], sp->target);
288 		if (err) {
289 			pr_warning("wf_pm72: Fan %s reports error %d\n",
290 			       cpu_rear_fans[cpu]->name, err);
291 			failure_state |= FAILURE_FAN;
292 			break;
293 		}
294 
295 		/* Scale result for intake fan */
296 		intake = (sp->target * CPU_INTAKE_SCALE) >> 16;
297 		DBG_LOTS("  CPU%d: intake = %d RPM\n", cpu, intake);
298 		err = wf_control_set(cpu_front_fans[cpu], intake);
299 		if (err) {
300 			pr_warning("wf_pm72: Fan %s reports error %d\n",
301 			       cpu_front_fans[cpu]->name, err);
302 			failure_state |= FAILURE_FAN;
303 			break;
304 		}
305 	}
306 }
307 
308 static void cpu_fans_tick_combined(void)
309 {
310 	s32 temp0, power0, temp1, power1, t_max = 0;
311 	s32 temp, power, intake, pump;
312 	struct wf_control *pump0, *pump1;
313 	struct wf_cpu_pid_state *sp = &cpu_pid[0];
314 	int err, cpu;
315 
316 	DBG_LOTS("* cpu fans_tick_combined()\n");
317 
318 	/* Read current speed from cpu 0 */
319 	wf_control_get(cpu_rear_fans[0], &sp->target);
320 
321 	DBG_LOTS("  CPUs: cur_target = %d RPM\n", sp->target);
322 
323 	/* Read values for both CPUs */
324 	err = read_one_cpu_vals(0, &temp0, &power0);
325 	if (err) {
326 		failure_state |= FAILURE_SENSOR;
327 		cpu_max_all_fans();
328 		return;
329 	}
330 	err = read_one_cpu_vals(1, &temp1, &power1);
331 	if (err) {
332 		failure_state |= FAILURE_SENSOR;
333 		cpu_max_all_fans();
334 		return;
335 	}
336 
337 	/* Keep track of highest temp */
338 	t_max = max(t_max, max(temp0, temp1));
339 
340 	/* Handle possible overtemps */
341 	if (cpu_check_overtemp(t_max))
342 		return;
343 
344 	/* Use the max temp & power of both */
345 	temp = max(temp0, temp1);
346 	power = max(power0, power1);
347 
348 	/* Run PID */
349 	wf_cpu_pid_run(sp, power, temp);
350 
351 	/* Scale result for intake fan */
352 	intake = (sp->target * CPU_INTAKE_SCALE) >> 16;
353 
354 	/* Same deal with pump speed */
355 	pump0 = cpu_pumps[0];
356 	pump1 = cpu_pumps[1];
357 	if (!pump0) {
358 		pump0 = pump1;
359 		pump1 = NULL;
360 	}
361 	pump = (sp->target * wf_control_get_max(pump0)) /
362 		cpu_mpu_data[0]->rmaxn_exhaust_fan;
363 
364 	DBG_LOTS("  CPUs: target = %d RPM\n", sp->target);
365 	DBG_LOTS("  CPUs: intake = %d RPM\n", intake);
366 	DBG_LOTS("  CPUs: pump   = %d RPM\n", pump);
367 
368 	for (cpu = 0; cpu < nr_chips; cpu++) {
369 		err = wf_control_set(cpu_rear_fans[cpu], sp->target);
370 		if (err) {
371 			pr_warning("wf_pm72: Fan %s reports error %d\n",
372 				   cpu_rear_fans[cpu]->name, err);
373 			failure_state |= FAILURE_FAN;
374 		}
375 		err = wf_control_set(cpu_front_fans[cpu], intake);
376 		if (err) {
377 			pr_warning("wf_pm72: Fan %s reports error %d\n",
378 				   cpu_front_fans[cpu]->name, err);
379 			failure_state |= FAILURE_FAN;
380 		}
381 		err = 0;
382 		if (cpu_pumps[cpu])
383 			err = wf_control_set(cpu_pumps[cpu], pump);
384 		if (err) {
385 			pr_warning("wf_pm72: Pump %s reports error %d\n",
386 				   cpu_pumps[cpu]->name, err);
387 			failure_state |= FAILURE_FAN;
388 		}
389 	}
390 }
391 
392 /* Implementation... */
393 static int cpu_setup_pid(int cpu)
394 {
395 	struct wf_cpu_pid_param pid;
396 	const struct mpu_data *mpu = cpu_mpu_data[cpu];
397 	s32 tmax, ttarget, ptarget;
398 	int fmin, fmax, hsize;
399 
400 	/* Get PID params from the appropriate MPU EEPROM */
401 	tmax = mpu->tmax << 16;
402 	ttarget = mpu->ttarget << 16;
403 	ptarget = ((s32)(mpu->pmaxh - mpu->padjmax)) << 16;
404 
405 	DBG("wf_72: CPU%d ttarget = %d.%03d, tmax = %d.%03d\n",
406 	    cpu, FIX32TOPRINT(ttarget), FIX32TOPRINT(tmax));
407 
408 	/* We keep a global tmax for overtemp calculations */
409 	if (tmax < cpu_all_tmax)
410 		cpu_all_tmax = tmax;
411 
412 	/* Set PID min/max by using the rear fan min/max */
413 	fmin = wf_control_get_min(cpu_rear_fans[cpu]);
414 	fmax = wf_control_get_max(cpu_rear_fans[cpu]);
415 	DBG("wf_72: CPU%d max RPM range = [%d..%d]\n", cpu, fmin, fmax);
416 
417 	/* History size */
418 	hsize = min_t(int, mpu->tguardband, WF_PID_MAX_HISTORY);
419 	DBG("wf_72: CPU%d history size = %d\n", cpu, hsize);
420 
421 	/* Initialize PID loop */
422 	pid.interval	= 1;	/* seconds */
423 	pid.history_len = hsize;
424 	pid.gd		= mpu->pid_gd;
425 	pid.gp		= mpu->pid_gp;
426 	pid.gr		= mpu->pid_gr;
427 	pid.tmax	= tmax;
428 	pid.ttarget	= ttarget;
429 	pid.pmaxadj	= ptarget;
430 	pid.min		= fmin;
431 	pid.max		= fmax;
432 
433 	wf_cpu_pid_init(&cpu_pid[cpu], &pid);
434 	cpu_pid[cpu].target = 1000;
435 
436 	return 0;
437 }
438 
439 /* Backside/U3 fan */
440 static struct wf_pid_param backside_u3_param = {
441 	.interval	= 5,
442 	.history_len	= 2,
443 	.gd		= 40 << 20,
444 	.gp		= 5 << 20,
445 	.gr		= 0,
446 	.itarget	= 65 << 16,
447 	.additive	= 1,
448 	.min		= 20,
449 	.max		= 100,
450 };
451 
452 static struct wf_pid_param backside_u3h_param = {
453 	.interval	= 5,
454 	.history_len	= 2,
455 	.gd		= 20 << 20,
456 	.gp		= 5 << 20,
457 	.gr		= 0,
458 	.itarget	= 75 << 16,
459 	.additive	= 1,
460 	.min		= 20,
461 	.max		= 100,
462 };
463 
464 static void backside_fan_tick(void)
465 {
466 	s32 temp;
467 	int speed;
468 	int err;
469 
470 	if (!backside_fan || !backside_temp || !backside_tick)
471 		return;
472 	if (--backside_tick > 0)
473 		return;
474 	backside_tick = backside_pid.param.interval;
475 
476 	DBG_LOTS("* backside fans tick\n");
477 
478 	/* Update fan speed from actual fans */
479 	err = wf_control_get(backside_fan, &speed);
480 	if (!err)
481 		backside_pid.target = speed;
482 
483 	err = wf_sensor_get(backside_temp, &temp);
484 	if (err) {
485 		printk(KERN_WARNING "windfarm: U4 temp sensor error %d\n",
486 		       err);
487 		failure_state |= FAILURE_SENSOR;
488 		wf_control_set_max(backside_fan);
489 		return;
490 	}
491 	speed = wf_pid_run(&backside_pid, temp);
492 
493 	DBG_LOTS("backside PID temp=%d.%.3d speed=%d\n",
494 		 FIX32TOPRINT(temp), speed);
495 
496 	err = wf_control_set(backside_fan, speed);
497 	if (err) {
498 		printk(KERN_WARNING "windfarm: backside fan error %d\n", err);
499 		failure_state |= FAILURE_FAN;
500 	}
501 }
502 
503 static void backside_setup_pid(void)
504 {
505 	/* first time initialize things */
506 	s32 fmin = wf_control_get_min(backside_fan);
507 	s32 fmax = wf_control_get_max(backside_fan);
508 	struct wf_pid_param param;
509 	struct device_node *u3;
510 	int u3h = 1; /* conservative by default */
511 
512 	u3 = of_find_node_by_path("/u3@0,f8000000");
513 	if (u3 != NULL) {
514 		const u32 *vers = of_get_property(u3, "device-rev", NULL);
515 		if (vers)
516 			if (((*vers) & 0x3f) < 0x34)
517 				u3h = 0;
518 		of_node_put(u3);
519 	}
520 
521 	param = u3h ? backside_u3h_param : backside_u3_param;
522 
523 	param.min = max(param.min, fmin);
524 	param.max = min(param.max, fmax);
525 	wf_pid_init(&backside_pid, &param);
526 	backside_tick = 1;
527 
528 	pr_info("wf_pm72: Backside control loop started.\n");
529 }
530 
531 /* Drive bay fan */
532 static const struct wf_pid_param drives_param = {
533 	.interval	= 5,
534 	.history_len	= 2,
535 	.gd		= 30 << 20,
536 	.gp		= 5 << 20,
537 	.gr		= 0,
538 	.itarget	= 40 << 16,
539 	.additive	= 1,
540 	.min		= 300,
541 	.max		= 4000,
542 };
543 
544 static void drives_fan_tick(void)
545 {
546 	s32 temp;
547 	int speed;
548 	int err;
549 
550 	if (!drives_fan || !drives_temp || !drives_tick)
551 		return;
552 	if (--drives_tick > 0)
553 		return;
554 	drives_tick = drives_pid.param.interval;
555 
556 	DBG_LOTS("* drives fans tick\n");
557 
558 	/* Update fan speed from actual fans */
559 	err = wf_control_get(drives_fan, &speed);
560 	if (!err)
561 		drives_pid.target = speed;
562 
563 	err = wf_sensor_get(drives_temp, &temp);
564 	if (err) {
565 		pr_warning("wf_pm72: drive bay temp sensor error %d\n", err);
566 		failure_state |= FAILURE_SENSOR;
567 		wf_control_set_max(drives_fan);
568 		return;
569 	}
570 	speed = wf_pid_run(&drives_pid, temp);
571 
572 	DBG_LOTS("drives PID temp=%d.%.3d speed=%d\n",
573 		 FIX32TOPRINT(temp), speed);
574 
575 	err = wf_control_set(drives_fan, speed);
576 	if (err) {
577 		printk(KERN_WARNING "windfarm: drive bay fan error %d\n", err);
578 		failure_state |= FAILURE_FAN;
579 	}
580 }
581 
582 static void drives_setup_pid(void)
583 {
584 	/* first time initialize things */
585 	s32 fmin = wf_control_get_min(drives_fan);
586 	s32 fmax = wf_control_get_max(drives_fan);
587 	struct wf_pid_param param = drives_param;
588 
589 	param.min = max(param.min, fmin);
590 	param.max = min(param.max, fmax);
591 	wf_pid_init(&drives_pid, &param);
592 	drives_tick = 1;
593 
594 	pr_info("wf_pm72: Drive bay control loop started.\n");
595 }
596 
597 static void set_fail_state(void)
598 {
599 	cpu_max_all_fans();
600 
601 	if (backside_fan)
602 		wf_control_set_max(backside_fan);
603 	if (slots_fan)
604 		wf_control_set_max(slots_fan);
605 	if (drives_fan)
606 		wf_control_set_max(drives_fan);
607 }
608 
609 static void pm72_tick(void)
610 {
611 	int i, last_failure;
612 
613 	if (!started) {
614 		started = true;
615 		printk(KERN_INFO "windfarm: CPUs control loops started.\n");
616 		for (i = 0; i < nr_chips; ++i) {
617 			if (cpu_setup_pid(i) < 0) {
618 				failure_state = FAILURE_PERM;
619 				set_fail_state();
620 				break;
621 			}
622 		}
623 		DBG_LOTS("cpu_all_tmax=%d.%03d\n", FIX32TOPRINT(cpu_all_tmax));
624 
625 		backside_setup_pid();
626 		drives_setup_pid();
627 
628 		/*
629 		 * We don't have the right stuff to drive the PCI fan
630 		 * so we fix it to a default value
631 		 */
632 		wf_control_set(slots_fan, SLOTS_FAN_DEFAULT_PWM);
633 
634 #ifdef HACKED_OVERTEMP
635 		cpu_all_tmax = 60 << 16;
636 #endif
637 	}
638 
639 	/* Permanent failure, bail out */
640 	if (failure_state & FAILURE_PERM)
641 		return;
642 
643 	/*
644 	 * Clear all failure bits except low overtemp which will be eventually
645 	 * cleared by the control loop itself
646 	 */
647 	last_failure = failure_state;
648 	failure_state &= FAILURE_LOW_OVERTEMP;
649 	if (cpu_pid_combined)
650 		cpu_fans_tick_combined();
651 	else
652 		cpu_fans_tick_split();
653 	backside_fan_tick();
654 	drives_fan_tick();
655 
656 	DBG_LOTS("  last_failure: 0x%x, failure_state: %x\n",
657 		 last_failure, failure_state);
658 
659 	/* Check for failures. Any failure causes cpufreq clamping */
660 	if (failure_state && last_failure == 0 && cpufreq_clamp)
661 		wf_control_set_max(cpufreq_clamp);
662 	if (failure_state == 0 && last_failure && cpufreq_clamp)
663 		wf_control_set_min(cpufreq_clamp);
664 
665 	/* That's it for now, we might want to deal with other failures
666 	 * differently in the future though
667 	 */
668 }
669 
670 static void pm72_new_control(struct wf_control *ct)
671 {
672 	bool all_controls;
673 	bool had_pump = cpu_pumps[0] || cpu_pumps[1];
674 
675 	if (!strcmp(ct->name, "cpu-front-fan-0"))
676 		cpu_front_fans[0] = ct;
677 	else if (!strcmp(ct->name, "cpu-front-fan-1"))
678 		cpu_front_fans[1] = ct;
679 	else if (!strcmp(ct->name, "cpu-rear-fan-0"))
680 		cpu_rear_fans[0] = ct;
681 	else if (!strcmp(ct->name, "cpu-rear-fan-1"))
682 		cpu_rear_fans[1] = ct;
683 	else if (!strcmp(ct->name, "cpu-pump-0"))
684 		cpu_pumps[0] = ct;
685 	else if (!strcmp(ct->name, "cpu-pump-1"))
686 		cpu_pumps[1] = ct;
687 	else if (!strcmp(ct->name, "backside-fan"))
688 		backside_fan = ct;
689 	else if (!strcmp(ct->name, "slots-fan"))
690 		slots_fan = ct;
691 	else if (!strcmp(ct->name, "drive-bay-fan"))
692 		drives_fan = ct;
693 	else if (!strcmp(ct->name, "cpufreq-clamp"))
694 		cpufreq_clamp = ct;
695 
696 	all_controls =
697 		cpu_front_fans[0] &&
698 		cpu_rear_fans[0] &&
699 		backside_fan &&
700 		slots_fan &&
701 		drives_fan;
702 	if (nr_chips > 1)
703 		all_controls &=
704 			cpu_front_fans[1] &&
705 			cpu_rear_fans[1];
706 	have_all_controls = all_controls;
707 
708 	if ((cpu_pumps[0] || cpu_pumps[1]) && !had_pump) {
709 		pr_info("wf_pm72: Liquid cooling pump(s) detected,"
710 			" using new algorithm !\n");
711 		cpu_pid_combined = true;
712 	}
713 }
714 
715 
716 static void pm72_new_sensor(struct wf_sensor *sr)
717 {
718 	bool all_sensors;
719 
720 	if (!strcmp(sr->name, "cpu-diode-temp-0"))
721 		sens_cpu_temp[0] = sr;
722 	else if (!strcmp(sr->name, "cpu-diode-temp-1"))
723 		sens_cpu_temp[1] = sr;
724 	else if (!strcmp(sr->name, "cpu-voltage-0"))
725 		sens_cpu_volts[0] = sr;
726 	else if (!strcmp(sr->name, "cpu-voltage-1"))
727 		sens_cpu_volts[1] = sr;
728 	else if (!strcmp(sr->name, "cpu-current-0"))
729 		sens_cpu_amps[0] = sr;
730 	else if (!strcmp(sr->name, "cpu-current-1"))
731 		sens_cpu_amps[1] = sr;
732 	else if (!strcmp(sr->name, "backside-temp"))
733 		backside_temp = sr;
734 	else if (!strcmp(sr->name, "hd-temp"))
735 		drives_temp = sr;
736 
737 	all_sensors =
738 		sens_cpu_temp[0] &&
739 		sens_cpu_volts[0] &&
740 		sens_cpu_amps[0] &&
741 		backside_temp &&
742 		drives_temp;
743 	if (nr_chips > 1)
744 		all_sensors &=
745 			sens_cpu_temp[1] &&
746 			sens_cpu_volts[1] &&
747 			sens_cpu_amps[1];
748 
749 	have_all_sensors = all_sensors;
750 }
751 
752 static int pm72_wf_notify(struct notifier_block *self,
753 			  unsigned long event, void *data)
754 {
755 	switch (event) {
756 	case WF_EVENT_NEW_SENSOR:
757 		pm72_new_sensor(data);
758 		break;
759 	case WF_EVENT_NEW_CONTROL:
760 		pm72_new_control(data);
761 		break;
762 	case WF_EVENT_TICK:
763 		if (have_all_controls && have_all_sensors)
764 			pm72_tick();
765 	}
766 	return 0;
767 }
768 
769 static struct notifier_block pm72_events = {
770 	.notifier_call = pm72_wf_notify,
771 };
772 
773 static int wf_pm72_probe(struct platform_device *dev)
774 {
775 	wf_register_client(&pm72_events);
776 	return 0;
777 }
778 
779 static int wf_pm72_remove(struct platform_device *dev)
780 {
781 	wf_unregister_client(&pm72_events);
782 
783 	/* should release all sensors and controls */
784 	return 0;
785 }
786 
787 static struct platform_driver wf_pm72_driver = {
788 	.probe	= wf_pm72_probe,
789 	.remove	= wf_pm72_remove,
790 	.driver	= {
791 		.name = "windfarm",
792 	},
793 };
794 
795 static int __init wf_pm72_init(void)
796 {
797 	struct device_node *cpu;
798 	int i;
799 
800 	if (!of_machine_is_compatible("PowerMac7,2") &&
801 	    !of_machine_is_compatible("PowerMac7,3"))
802 		return -ENODEV;
803 
804 	/* Count the number of CPU cores */
805 	nr_chips = 0;
806 	for_each_node_by_type(cpu, "cpu")
807 		++nr_chips;
808 	if (nr_chips > NR_CHIPS)
809 		nr_chips = NR_CHIPS;
810 
811 	pr_info("windfarm: Initializing for desktop G5 with %d chips\n",
812 		nr_chips);
813 
814 	/* Get MPU data for each CPU */
815 	for (i = 0; i < nr_chips; i++) {
816 		cpu_mpu_data[i] = wf_get_mpu(i);
817 		if (!cpu_mpu_data[i]) {
818 			pr_err("wf_pm72: Failed to find MPU data for CPU %d\n", i);
819 			return -ENXIO;
820 		}
821 	}
822 
823 #ifdef MODULE
824 	request_module("windfarm_fcu_controls");
825 	request_module("windfarm_lm75_sensor");
826 	request_module("windfarm_ad7417_sensor");
827 	request_module("windfarm_max6690_sensor");
828 	request_module("windfarm_cpufreq_clamp");
829 #endif /* MODULE */
830 
831 	platform_driver_register(&wf_pm72_driver);
832 	return 0;
833 }
834 
835 static void __exit wf_pm72_exit(void)
836 {
837 	platform_driver_unregister(&wf_pm72_driver);
838 }
839 
840 module_init(wf_pm72_init);
841 module_exit(wf_pm72_exit);
842 
843 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
844 MODULE_DESCRIPTION("Thermal control for AGP PowerMac G5s");
845 MODULE_LICENSE("GPL");
846 MODULE_ALIAS("platform:windfarm");
847