xref: /linux/drivers/macintosh/windfarm_pm121.c (revision 0d3b051adbb72ed81956447d0d1e54d5943ee6f5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Windfarm PowerMac thermal control. iMac G5 iSight
4  *
5  * (c) Copyright 2007 Étienne Bersac <bersace@gmail.com>
6  *
7  * Bits & pieces from windfarm_pm81.c by (c) Copyright 2005 Benjamin
8  * Herrenschmidt, IBM Corp. <benh@kernel.crashing.org>
9  *
10  * PowerMac12,1
11  * ============
12  *
13  * The algorithm used is the PID control algorithm, used the same way
14  * the published Darwin code does, using the same values that are
15  * present in the Darwin 8.10 snapshot property lists (note however
16  * that none of the code has been re-used, it's a complete
17  * re-implementation
18  *
19  * There is two models using PowerMac12,1. Model 2 is iMac G5 iSight
20  * 17" while Model 3 is iMac G5 20". They do have both the same
21  * controls with a tiny difference. The control-ids of hard-drive-fan
22  * and cpu-fan is swapped.
23  *
24  * Target Correction :
25  *
26  * controls have a target correction calculated as :
27  *
28  * new_min = ((((average_power * slope) >> 16) + offset) >> 16) + min_value
29  * new_value = max(new_value, max(new_min, 0))
30  *
31  * OD Fan control correction.
32  *
33  * # model_id: 2
34  *   offset		: -19563152
35  *   slope		:  1956315
36  *
37  * # model_id: 3
38  *   offset		: -15650652
39  *   slope		:  1565065
40  *
41  * HD Fan control correction.
42  *
43  * # model_id: 2
44  *   offset		: -15650652
45  *   slope		:  1565065
46  *
47  * # model_id: 3
48  *   offset		: -19563152
49  *   slope		:  1956315
50  *
51  * CPU Fan control correction.
52  *
53  * # model_id: 2
54  *   offset		: -25431900
55  *   slope		:  2543190
56  *
57  * # model_id: 3
58  *   offset		: -15650652
59  *   slope		:  1565065
60  *
61  * Target rubber-banding :
62  *
63  * Some controls have a target correction which depends on another
64  * control value. The correction is computed in the following way :
65  *
66  * new_min = ref_value * slope + offset
67  *
68  * ref_value is the value of the reference control. If new_min is
69  * greater than 0, then we correct the target value using :
70  *
71  * new_target = max (new_target, new_min >> 16)
72  *
73  * # model_id : 2
74  *   control	: cpu-fan
75  *   ref	: optical-drive-fan
76  *   offset	: -15650652
77  *   slope	: 1565065
78  *
79  * # model_id : 3
80  *   control	: optical-drive-fan
81  *   ref	: hard-drive-fan
82  *   offset	: -32768000
83  *   slope	: 65536
84  *
85  * In order to have the moste efficient correction with those
86  * dependencies, we must trigger HD loop before OD loop before CPU
87  * loop.
88  *
89  * The various control loops found in Darwin config file are:
90  *
91  * HD Fan control loop.
92  *
93  * # model_id: 2
94  *   control        : hard-drive-fan
95  *   sensor         : hard-drive-temp
96  *   PID params     : G_d = 0x00000000
97  *                    G_p = 0x002D70A3
98  *                    G_r = 0x00019999
99  *                    History = 2 entries
100  *                    Input target = 0x370000
101  *                    Interval = 5s
102  *
103  * # model_id: 3
104  *   control        : hard-drive-fan
105  *   sensor         : hard-drive-temp
106  *   PID params     : G_d = 0x00000000
107  *                    G_p = 0x002170A3
108  *                    G_r = 0x00019999
109  *                    History = 2 entries
110  *                    Input target = 0x370000
111  *                    Interval = 5s
112  *
113  * OD Fan control loop.
114  *
115  * # model_id: 2
116  *   control        : optical-drive-fan
117  *   sensor         : optical-drive-temp
118  *   PID params     : G_d = 0x00000000
119  *                    G_p = 0x001FAE14
120  *                    G_r = 0x00019999
121  *                    History = 2 entries
122  *                    Input target = 0x320000
123  *                    Interval = 5s
124  *
125  * # model_id: 3
126  *   control        : optical-drive-fan
127  *   sensor         : optical-drive-temp
128  *   PID params     : G_d = 0x00000000
129  *                    G_p = 0x001FAE14
130  *                    G_r = 0x00019999
131  *                    History = 2 entries
132  *                    Input target = 0x320000
133  *                    Interval = 5s
134  *
135  * GPU Fan control loop.
136  *
137  * # model_id: 2
138  *   control        : hard-drive-fan
139  *   sensor         : gpu-temp
140  *   PID params     : G_d = 0x00000000
141  *                    G_p = 0x002A6666
142  *                    G_r = 0x00019999
143  *                    History = 2 entries
144  *                    Input target = 0x5A0000
145  *                    Interval = 5s
146  *
147  * # model_id: 3
148  *   control        : cpu-fan
149  *   sensor         : gpu-temp
150  *   PID params     : G_d = 0x00000000
151  *                    G_p = 0x0010CCCC
152  *                    G_r = 0x00019999
153  *                    History = 2 entries
154  *                    Input target = 0x500000
155  *                    Interval = 5s
156  *
157  * KODIAK (aka northbridge) Fan control loop.
158  *
159  * # model_id: 2
160  *   control        : optical-drive-fan
161  *   sensor         : north-bridge-temp
162  *   PID params     : G_d = 0x00000000
163  *                    G_p = 0x003BD70A
164  *                    G_r = 0x00019999
165  *                    History = 2 entries
166  *                    Input target = 0x550000
167  *                    Interval = 5s
168  *
169  * # model_id: 3
170  *   control        : hard-drive-fan
171  *   sensor         : north-bridge-temp
172  *   PID params     : G_d = 0x00000000
173  *                    G_p = 0x0030F5C2
174  *                    G_r = 0x00019999
175  *                    History = 2 entries
176  *                    Input target = 0x550000
177  *                    Interval = 5s
178  *
179  * CPU Fan control loop.
180  *
181  *   control        : cpu-fan
182  *   sensors        : cpu-temp, cpu-power
183  *   PID params     : from SDB partition
184  *
185  * CPU Slew control loop.
186  *
187  *   control        : cpufreq-clamp
188  *   sensor         : cpu-temp
189  */
190 
191 #undef	DEBUG
192 
193 #include <linux/types.h>
194 #include <linux/errno.h>
195 #include <linux/kernel.h>
196 #include <linux/delay.h>
197 #include <linux/slab.h>
198 #include <linux/init.h>
199 #include <linux/spinlock.h>
200 #include <linux/wait.h>
201 #include <linux/kmod.h>
202 #include <linux/device.h>
203 #include <linux/platform_device.h>
204 #include <asm/prom.h>
205 #include <asm/machdep.h>
206 #include <asm/io.h>
207 #include <asm/sections.h>
208 #include <asm/smu.h>
209 
210 #include "windfarm.h"
211 #include "windfarm_pid.h"
212 
213 #define VERSION "0.3"
214 
215 static int pm121_mach_model;	/* machine model id */
216 
217 /* Controls & sensors */
218 static struct wf_sensor	*sensor_cpu_power;
219 static struct wf_sensor	*sensor_cpu_temp;
220 static struct wf_sensor	*sensor_cpu_voltage;
221 static struct wf_sensor	*sensor_cpu_current;
222 static struct wf_sensor	*sensor_gpu_temp;
223 static struct wf_sensor	*sensor_north_bridge_temp;
224 static struct wf_sensor	*sensor_hard_drive_temp;
225 static struct wf_sensor	*sensor_optical_drive_temp;
226 static struct wf_sensor	*sensor_incoming_air_temp; /* unused ! */
227 
228 enum {
229 	FAN_CPU,
230 	FAN_HD,
231 	FAN_OD,
232 	CPUFREQ,
233 	N_CONTROLS
234 };
235 static struct wf_control *controls[N_CONTROLS] = {};
236 
237 /* Set to kick the control loop into life */
238 static int pm121_all_controls_ok, pm121_all_sensors_ok;
239 static bool pm121_started;
240 
241 enum {
242 	FAILURE_FAN		= 1 << 0,
243 	FAILURE_SENSOR		= 1 << 1,
244 	FAILURE_OVERTEMP	= 1 << 2
245 };
246 
247 /* All sys loops. Note the HD before the OD loop in order to have it
248    run before. */
249 enum {
250 	LOOP_GPU,		/* control = hd or cpu, but luckily,
251 				   it doesn't matter */
252 	LOOP_HD,		/* control = hd */
253 	LOOP_KODIAK,		/* control = hd or od */
254 	LOOP_OD,		/* control = od */
255 	N_LOOPS
256 };
257 
258 static const char *loop_names[N_LOOPS] = {
259 	"GPU",
260 	"HD",
261 	"KODIAK",
262 	"OD",
263 };
264 
265 #define	PM121_NUM_CONFIGS	2
266 
267 static unsigned int pm121_failure_state;
268 static int pm121_readjust, pm121_skipping;
269 static bool pm121_overtemp;
270 static s32 average_power;
271 
272 struct pm121_correction {
273 	int	offset;
274 	int	slope;
275 };
276 
277 static struct pm121_correction corrections[N_CONTROLS][PM121_NUM_CONFIGS] = {
278 	/* FAN_OD */
279 	{
280 		/* MODEL 2 */
281 		{ .offset	= -19563152,
282 		  .slope	=  1956315
283 		},
284 		/* MODEL 3 */
285 		{ .offset	= -15650652,
286 		  .slope	=  1565065
287 		},
288 	},
289 	/* FAN_HD */
290 	{
291 		/* MODEL 2 */
292 		{ .offset	= -15650652,
293 		  .slope	=  1565065
294 		},
295 		/* MODEL 3 */
296 		{ .offset	= -19563152,
297 		  .slope	=  1956315
298 		},
299 	},
300 	/* FAN_CPU */
301 	{
302 		/* MODEL 2 */
303 		{ .offset	= -25431900,
304 		  .slope	=  2543190
305 		},
306 		/* MODEL 3 */
307 		{ .offset	= -15650652,
308 		  .slope	=  1565065
309 		},
310 	},
311 	/* CPUFREQ has no correction (and is not implemented at all) */
312 };
313 
314 struct pm121_connection {
315 	unsigned int	control_id;
316 	unsigned int	ref_id;
317 	struct pm121_correction	correction;
318 };
319 
320 static struct pm121_connection pm121_connections[] = {
321 	/* MODEL 2 */
322 	{ .control_id	= FAN_CPU,
323 	  .ref_id	= FAN_OD,
324 	  { .offset	= -32768000,
325 	    .slope	=  65536
326 	  }
327 	},
328 	/* MODEL 3 */
329 	{ .control_id	= FAN_OD,
330 	  .ref_id	= FAN_HD,
331 	  { .offset	= -32768000,
332 	    .slope	=  65536
333 	  }
334 	},
335 };
336 
337 /* pointer to the current model connection */
338 static struct pm121_connection *pm121_connection;
339 
340 /*
341  * ****** System Fans Control Loop ******
342  *
343  */
344 
345 /* Since each loop handles only one control and we want to avoid
346  * writing virtual control, we store the control correction with the
347  * loop params. Some data are not set, there are common to all loop
348  * and thus, hardcoded.
349  */
350 struct pm121_sys_param {
351 	/* purely informative since we use mach_model-2 as index */
352 	int			model_id;
353 	struct wf_sensor	**sensor; /* use sensor_id instead ? */
354 	s32			gp, itarget;
355 	unsigned int		control_id;
356 };
357 
358 static struct pm121_sys_param
359 pm121_sys_all_params[N_LOOPS][PM121_NUM_CONFIGS] = {
360 	/* GPU Fan control loop */
361 	{
362 		{ .model_id	= 2,
363 		  .sensor	= &sensor_gpu_temp,
364 		  .gp		= 0x002A6666,
365 		  .itarget	= 0x5A0000,
366 		  .control_id	= FAN_HD,
367 		},
368 		{ .model_id	= 3,
369 		  .sensor	= &sensor_gpu_temp,
370 		  .gp		= 0x0010CCCC,
371 		  .itarget	= 0x500000,
372 		  .control_id	= FAN_CPU,
373 		},
374 	},
375 	/* HD Fan control loop */
376 	{
377 		{ .model_id	= 2,
378 		  .sensor	= &sensor_hard_drive_temp,
379 		  .gp		= 0x002D70A3,
380 		  .itarget	= 0x370000,
381 		  .control_id	= FAN_HD,
382 		},
383 		{ .model_id	= 3,
384 		  .sensor	= &sensor_hard_drive_temp,
385 		  .gp		= 0x002170A3,
386 		  .itarget	= 0x370000,
387 		  .control_id	= FAN_HD,
388 		},
389 	},
390 	/* KODIAK Fan control loop */
391 	{
392 		{ .model_id	= 2,
393 		  .sensor	= &sensor_north_bridge_temp,
394 		  .gp		= 0x003BD70A,
395 		  .itarget	= 0x550000,
396 		  .control_id	= FAN_OD,
397 		},
398 		{ .model_id	= 3,
399 		  .sensor	= &sensor_north_bridge_temp,
400 		  .gp		= 0x0030F5C2,
401 		  .itarget	= 0x550000,
402 		  .control_id	= FAN_HD,
403 		},
404 	},
405 	/* OD Fan control loop */
406 	{
407 		{ .model_id	= 2,
408 		  .sensor	= &sensor_optical_drive_temp,
409 		  .gp		= 0x001FAE14,
410 		  .itarget	= 0x320000,
411 		  .control_id	= FAN_OD,
412 		},
413 		{ .model_id	= 3,
414 		  .sensor	= &sensor_optical_drive_temp,
415 		  .gp		= 0x001FAE14,
416 		  .itarget	= 0x320000,
417 		  .control_id	= FAN_OD,
418 		},
419 	},
420 };
421 
422 /* the hardcoded values */
423 #define	PM121_SYS_GD		0x00000000
424 #define	PM121_SYS_GR		0x00019999
425 #define	PM121_SYS_HISTORY_SIZE	2
426 #define	PM121_SYS_INTERVAL	5
427 
428 /* State data used by the system fans control loop
429  */
430 struct pm121_sys_state {
431 	int			ticks;
432 	s32			setpoint;
433 	struct wf_pid_state	pid;
434 };
435 
436 struct pm121_sys_state *pm121_sys_state[N_LOOPS] = {};
437 
438 /*
439  * ****** CPU Fans Control Loop ******
440  *
441  */
442 
443 #define PM121_CPU_INTERVAL	1
444 
445 /* State data used by the cpu fans control loop
446  */
447 struct pm121_cpu_state {
448 	int			ticks;
449 	s32			setpoint;
450 	struct wf_cpu_pid_state	pid;
451 };
452 
453 static struct pm121_cpu_state *pm121_cpu_state;
454 
455 
456 
457 /*
458  * ***** Implementation *****
459  *
460  */
461 
462 /* correction the value using the output-low-bound correction algo */
463 static s32 pm121_correct(s32 new_setpoint,
464 			 unsigned int control_id,
465 			 s32 min)
466 {
467 	s32 new_min;
468 	struct pm121_correction *correction;
469 	correction = &corrections[control_id][pm121_mach_model - 2];
470 
471 	new_min = (average_power * correction->slope) >> 16;
472 	new_min += correction->offset;
473 	new_min = (new_min >> 16) + min;
474 
475 	return max3(new_setpoint, new_min, 0);
476 }
477 
478 static s32 pm121_connect(unsigned int control_id, s32 setpoint)
479 {
480 	s32 new_min, value, new_setpoint;
481 
482 	if (pm121_connection->control_id == control_id) {
483 		controls[control_id]->ops->get_value(controls[control_id],
484 						     &value);
485 		new_min = value * pm121_connection->correction.slope;
486 		new_min += pm121_connection->correction.offset;
487 		if (new_min > 0) {
488 			new_setpoint = max(setpoint, (new_min >> 16));
489 			if (new_setpoint != setpoint) {
490 				pr_debug("pm121: %s depending on %s, "
491 					 "corrected from %d to %d RPM\n",
492 					 controls[control_id]->name,
493 					 controls[pm121_connection->ref_id]->name,
494 					 (int) setpoint, (int) new_setpoint);
495 			}
496 		} else
497 			new_setpoint = setpoint;
498 	}
499 	/* no connection */
500 	else
501 		new_setpoint = setpoint;
502 
503 	return new_setpoint;
504 }
505 
506 /* FAN LOOPS */
507 static void pm121_create_sys_fans(int loop_id)
508 {
509 	struct pm121_sys_param *param = NULL;
510 	struct wf_pid_param pid_param;
511 	struct wf_control *control = NULL;
512 	int i;
513 
514 	/* First, locate the params for this model */
515 	for (i = 0; i < PM121_NUM_CONFIGS; i++) {
516 		if (pm121_sys_all_params[loop_id][i].model_id == pm121_mach_model) {
517 			param = &(pm121_sys_all_params[loop_id][i]);
518 			break;
519 		}
520 	}
521 
522 	/* No params found, put fans to max */
523 	if (param == NULL) {
524 		printk(KERN_WARNING "pm121: %s fan config not found "
525 		       " for this machine model\n",
526 		       loop_names[loop_id]);
527 		goto fail;
528 	}
529 
530 	control = controls[param->control_id];
531 
532 	/* Alloc & initialize state */
533 	pm121_sys_state[loop_id] = kmalloc(sizeof(struct pm121_sys_state),
534 					   GFP_KERNEL);
535 	if (pm121_sys_state[loop_id] == NULL) {
536 		printk(KERN_WARNING "pm121: Memory allocation error\n");
537 		goto fail;
538 	}
539 	pm121_sys_state[loop_id]->ticks = 1;
540 
541 	/* Fill PID params */
542 	pid_param.gd		= PM121_SYS_GD;
543 	pid_param.gp		= param->gp;
544 	pid_param.gr		= PM121_SYS_GR;
545 	pid_param.interval	= PM121_SYS_INTERVAL;
546 	pid_param.history_len	= PM121_SYS_HISTORY_SIZE;
547 	pid_param.itarget	= param->itarget;
548 	if(control)
549 	{
550 		pid_param.min		= control->ops->get_min(control);
551 		pid_param.max		= control->ops->get_max(control);
552 	} else {
553 		/*
554 		 * This is probably not the right!?
555 		 * Perhaps goto fail  if control == NULL  above?
556 		 */
557 		pid_param.min		= 0;
558 		pid_param.max		= 0;
559 	}
560 
561 	wf_pid_init(&pm121_sys_state[loop_id]->pid, &pid_param);
562 
563 	pr_debug("pm121: %s Fan control loop initialized.\n"
564 		 "       itarged=%d.%03d, min=%d RPM, max=%d RPM\n",
565 		 loop_names[loop_id], FIX32TOPRINT(pid_param.itarget),
566 		 pid_param.min, pid_param.max);
567 	return;
568 
569  fail:
570 	/* note that this is not optimal since another loop may still
571 	   control the same control */
572 	printk(KERN_WARNING "pm121: failed to set up %s loop "
573 	       "setting \"%s\" to max speed.\n",
574 	       loop_names[loop_id], control ? control->name : "uninitialized value");
575 
576 	if (control)
577 		wf_control_set_max(control);
578 }
579 
580 static void pm121_sys_fans_tick(int loop_id)
581 {
582 	struct pm121_sys_param *param;
583 	struct pm121_sys_state *st;
584 	struct wf_sensor *sensor;
585 	struct wf_control *control;
586 	s32 temp, new_setpoint;
587 	int rc;
588 
589 	param = &(pm121_sys_all_params[loop_id][pm121_mach_model-2]);
590 	st = pm121_sys_state[loop_id];
591 	sensor = *(param->sensor);
592 	control = controls[param->control_id];
593 
594 	if (--st->ticks != 0) {
595 		if (pm121_readjust)
596 			goto readjust;
597 		return;
598 	}
599 	st->ticks = PM121_SYS_INTERVAL;
600 
601 	rc = sensor->ops->get_value(sensor, &temp);
602 	if (rc) {
603 		printk(KERN_WARNING "windfarm: %s sensor error %d\n",
604 		       sensor->name, rc);
605 		pm121_failure_state |= FAILURE_SENSOR;
606 		return;
607 	}
608 
609 	pr_debug("pm121: %s Fan tick ! %s: %d.%03d\n",
610 		 loop_names[loop_id], sensor->name,
611 		 FIX32TOPRINT(temp));
612 
613 	new_setpoint = wf_pid_run(&st->pid, temp);
614 
615 	/* correction */
616 	new_setpoint = pm121_correct(new_setpoint,
617 				     param->control_id,
618 				     st->pid.param.min);
619 	/* linked corretion */
620 	new_setpoint = pm121_connect(param->control_id, new_setpoint);
621 
622 	if (new_setpoint == st->setpoint)
623 		return;
624 	st->setpoint = new_setpoint;
625 	pr_debug("pm121: %s corrected setpoint: %d RPM\n",
626 		 control->name, (int)new_setpoint);
627  readjust:
628 	if (control && pm121_failure_state == 0) {
629 		rc = control->ops->set_value(control, st->setpoint);
630 		if (rc) {
631 			printk(KERN_WARNING "windfarm: %s fan error %d\n",
632 			       control->name, rc);
633 			pm121_failure_state |= FAILURE_FAN;
634 		}
635 	}
636 }
637 
638 
639 /* CPU LOOP */
640 static void pm121_create_cpu_fans(void)
641 {
642 	struct wf_cpu_pid_param pid_param;
643 	const struct smu_sdbp_header *hdr;
644 	struct smu_sdbp_cpupiddata *piddata;
645 	struct smu_sdbp_fvt *fvt;
646 	struct wf_control *fan_cpu;
647 	s32 tmax, tdelta, maxpow, powadj;
648 
649 	fan_cpu = controls[FAN_CPU];
650 
651 	/* First, locate the PID params in SMU SBD */
652 	hdr = smu_get_sdb_partition(SMU_SDB_CPUPIDDATA_ID, NULL);
653 	if (hdr == 0) {
654 		printk(KERN_WARNING "pm121: CPU PID fan config not found.\n");
655 		goto fail;
656 	}
657 	piddata = (struct smu_sdbp_cpupiddata *)&hdr[1];
658 
659 	/* Get the FVT params for operating point 0 (the only supported one
660 	 * for now) in order to get tmax
661 	 */
662 	hdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL);
663 	if (hdr) {
664 		fvt = (struct smu_sdbp_fvt *)&hdr[1];
665 		tmax = ((s32)fvt->maxtemp) << 16;
666 	} else
667 		tmax = 0x5e0000; /* 94 degree default */
668 
669 	/* Alloc & initialize state */
670 	pm121_cpu_state = kmalloc(sizeof(struct pm121_cpu_state),
671 				  GFP_KERNEL);
672 	if (pm121_cpu_state == NULL)
673 		goto fail;
674 	pm121_cpu_state->ticks = 1;
675 
676 	/* Fill PID params */
677 	pid_param.interval = PM121_CPU_INTERVAL;
678 	pid_param.history_len = piddata->history_len;
679 	if (pid_param.history_len > WF_CPU_PID_MAX_HISTORY) {
680 		printk(KERN_WARNING "pm121: History size overflow on "
681 		       "CPU control loop (%d)\n", piddata->history_len);
682 		pid_param.history_len = WF_CPU_PID_MAX_HISTORY;
683 	}
684 	pid_param.gd = piddata->gd;
685 	pid_param.gp = piddata->gp;
686 	pid_param.gr = piddata->gr / pid_param.history_len;
687 
688 	tdelta = ((s32)piddata->target_temp_delta) << 16;
689 	maxpow = ((s32)piddata->max_power) << 16;
690 	powadj = ((s32)piddata->power_adj) << 16;
691 
692 	pid_param.tmax = tmax;
693 	pid_param.ttarget = tmax - tdelta;
694 	pid_param.pmaxadj = maxpow - powadj;
695 
696 	pid_param.min = fan_cpu->ops->get_min(fan_cpu);
697 	pid_param.max = fan_cpu->ops->get_max(fan_cpu);
698 
699 	wf_cpu_pid_init(&pm121_cpu_state->pid, &pid_param);
700 
701 	pr_debug("pm121: CPU Fan control initialized.\n");
702 	pr_debug("       ttarget=%d.%03d, tmax=%d.%03d, min=%d RPM, max=%d RPM,\n",
703 		 FIX32TOPRINT(pid_param.ttarget), FIX32TOPRINT(pid_param.tmax),
704 		 pid_param.min, pid_param.max);
705 
706 	return;
707 
708  fail:
709 	printk(KERN_WARNING "pm121: CPU fan config not found, max fan speed\n");
710 
711 	if (controls[CPUFREQ])
712 		wf_control_set_max(controls[CPUFREQ]);
713 	if (fan_cpu)
714 		wf_control_set_max(fan_cpu);
715 }
716 
717 
718 static void pm121_cpu_fans_tick(struct pm121_cpu_state *st)
719 {
720 	s32 new_setpoint, temp, power;
721 	struct wf_control *fan_cpu = NULL;
722 	int rc;
723 
724 	if (--st->ticks != 0) {
725 		if (pm121_readjust)
726 			goto readjust;
727 		return;
728 	}
729 	st->ticks = PM121_CPU_INTERVAL;
730 
731 	fan_cpu = controls[FAN_CPU];
732 
733 	rc = sensor_cpu_temp->ops->get_value(sensor_cpu_temp, &temp);
734 	if (rc) {
735 		printk(KERN_WARNING "pm121: CPU temp sensor error %d\n",
736 		       rc);
737 		pm121_failure_state |= FAILURE_SENSOR;
738 		return;
739 	}
740 
741 	rc = sensor_cpu_power->ops->get_value(sensor_cpu_power, &power);
742 	if (rc) {
743 		printk(KERN_WARNING "pm121: CPU power sensor error %d\n",
744 		       rc);
745 		pm121_failure_state |= FAILURE_SENSOR;
746 		return;
747 	}
748 
749 	pr_debug("pm121: CPU Fans tick ! CPU temp: %d.%03d°C, power: %d.%03d\n",
750 		 FIX32TOPRINT(temp), FIX32TOPRINT(power));
751 
752 	if (temp > st->pid.param.tmax)
753 		pm121_failure_state |= FAILURE_OVERTEMP;
754 
755 	new_setpoint = wf_cpu_pid_run(&st->pid, power, temp);
756 
757 	/* correction */
758 	new_setpoint = pm121_correct(new_setpoint,
759 				     FAN_CPU,
760 				     st->pid.param.min);
761 
762 	/* connected correction */
763 	new_setpoint = pm121_connect(FAN_CPU, new_setpoint);
764 
765 	if (st->setpoint == new_setpoint)
766 		return;
767 	st->setpoint = new_setpoint;
768 	pr_debug("pm121: CPU corrected setpoint: %d RPM\n", (int)new_setpoint);
769 
770  readjust:
771 	if (fan_cpu && pm121_failure_state == 0) {
772 		rc = fan_cpu->ops->set_value(fan_cpu, st->setpoint);
773 		if (rc) {
774 			printk(KERN_WARNING "pm121: %s fan error %d\n",
775 			       fan_cpu->name, rc);
776 			pm121_failure_state |= FAILURE_FAN;
777 		}
778 	}
779 }
780 
781 /*
782  * ****** Common ******
783  *
784  */
785 
786 static void pm121_tick(void)
787 {
788 	unsigned int last_failure = pm121_failure_state;
789 	unsigned int new_failure;
790 	s32 total_power;
791 	int i;
792 
793 	if (!pm121_started) {
794 		pr_debug("pm121: creating control loops !\n");
795 		for (i = 0; i < N_LOOPS; i++)
796 			pm121_create_sys_fans(i);
797 
798 		pm121_create_cpu_fans();
799 		pm121_started = true;
800 	}
801 
802 	/* skipping ticks */
803 	if (pm121_skipping && --pm121_skipping)
804 		return;
805 
806 	/* compute average power */
807 	total_power = 0;
808 	for (i = 0; i < pm121_cpu_state->pid.param.history_len; i++)
809 		total_power += pm121_cpu_state->pid.powers[i];
810 
811 	average_power = total_power / pm121_cpu_state->pid.param.history_len;
812 
813 
814 	pm121_failure_state = 0;
815 	for (i = 0 ; i < N_LOOPS; i++) {
816 		if (pm121_sys_state[i])
817 			pm121_sys_fans_tick(i);
818 	}
819 
820 	if (pm121_cpu_state)
821 		pm121_cpu_fans_tick(pm121_cpu_state);
822 
823 	pm121_readjust = 0;
824 	new_failure = pm121_failure_state & ~last_failure;
825 
826 	/* If entering failure mode, clamp cpufreq and ramp all
827 	 * fans to full speed.
828 	 */
829 	if (pm121_failure_state && !last_failure) {
830 		for (i = 0; i < N_CONTROLS; i++) {
831 			if (controls[i])
832 				wf_control_set_max(controls[i]);
833 		}
834 	}
835 
836 	/* If leaving failure mode, unclamp cpufreq and readjust
837 	 * all fans on next iteration
838 	 */
839 	if (!pm121_failure_state && last_failure) {
840 		if (controls[CPUFREQ])
841 			wf_control_set_min(controls[CPUFREQ]);
842 		pm121_readjust = 1;
843 	}
844 
845 	/* Overtemp condition detected, notify and start skipping a couple
846 	 * ticks to let the temperature go down
847 	 */
848 	if (new_failure & FAILURE_OVERTEMP) {
849 		wf_set_overtemp();
850 		pm121_skipping = 2;
851 		pm121_overtemp = true;
852 	}
853 
854 	/* We only clear the overtemp condition if overtemp is cleared
855 	 * _and_ no other failure is present. Since a sensor error will
856 	 * clear the overtemp condition (can't measure temperature) at
857 	 * the control loop levels, but we don't want to keep it clear
858 	 * here in this case
859 	 */
860 	if (!pm121_failure_state && pm121_overtemp) {
861 		wf_clear_overtemp();
862 		pm121_overtemp = false;
863 	}
864 }
865 
866 
867 static struct wf_control* pm121_register_control(struct wf_control *ct,
868 						 const char *match,
869 						 unsigned int id)
870 {
871 	if (controls[id] == NULL && !strcmp(ct->name, match)) {
872 		if (wf_get_control(ct) == 0)
873 			controls[id] = ct;
874 	}
875 	return controls[id];
876 }
877 
878 static void pm121_new_control(struct wf_control *ct)
879 {
880 	int all = 1;
881 
882 	if (pm121_all_controls_ok)
883 		return;
884 
885 	all = pm121_register_control(ct, "optical-drive-fan", FAN_OD) && all;
886 	all = pm121_register_control(ct, "hard-drive-fan", FAN_HD) && all;
887 	all = pm121_register_control(ct, "cpu-fan", FAN_CPU) && all;
888 	all = pm121_register_control(ct, "cpufreq-clamp", CPUFREQ) && all;
889 
890 	if (all)
891 		pm121_all_controls_ok = 1;
892 }
893 
894 
895 
896 
897 static struct wf_sensor* pm121_register_sensor(struct wf_sensor *sensor,
898 					       const char *match,
899 					       struct wf_sensor **var)
900 {
901 	if (*var == NULL && !strcmp(sensor->name, match)) {
902 		if (wf_get_sensor(sensor) == 0)
903 			*var = sensor;
904 	}
905 	return *var;
906 }
907 
908 static void pm121_new_sensor(struct wf_sensor *sr)
909 {
910 	int all = 1;
911 
912 	if (pm121_all_sensors_ok)
913 		return;
914 
915 	all = pm121_register_sensor(sr, "cpu-temp",
916 				    &sensor_cpu_temp) && all;
917 	all = pm121_register_sensor(sr, "cpu-current",
918 				    &sensor_cpu_current) && all;
919 	all = pm121_register_sensor(sr, "cpu-voltage",
920 				    &sensor_cpu_voltage) && all;
921 	all = pm121_register_sensor(sr, "cpu-power",
922 				    &sensor_cpu_power) && all;
923 	all = pm121_register_sensor(sr, "hard-drive-temp",
924 				    &sensor_hard_drive_temp) && all;
925 	all = pm121_register_sensor(sr, "optical-drive-temp",
926 				    &sensor_optical_drive_temp) && all;
927 	all = pm121_register_sensor(sr, "incoming-air-temp",
928 				    &sensor_incoming_air_temp) && all;
929 	all = pm121_register_sensor(sr, "north-bridge-temp",
930 				    &sensor_north_bridge_temp) && all;
931 	all = pm121_register_sensor(sr, "gpu-temp",
932 				    &sensor_gpu_temp) && all;
933 
934 	if (all)
935 		pm121_all_sensors_ok = 1;
936 }
937 
938 
939 
940 static int pm121_notify(struct notifier_block *self,
941 			unsigned long event, void *data)
942 {
943 	switch (event) {
944 	case WF_EVENT_NEW_CONTROL:
945 		pr_debug("pm121: new control %s detected\n",
946 			 ((struct wf_control *)data)->name);
947 		pm121_new_control(data);
948 		break;
949 	case WF_EVENT_NEW_SENSOR:
950 		pr_debug("pm121: new sensor %s detected\n",
951 			 ((struct wf_sensor *)data)->name);
952 		pm121_new_sensor(data);
953 		break;
954 	case WF_EVENT_TICK:
955 		if (pm121_all_controls_ok && pm121_all_sensors_ok)
956 			pm121_tick();
957 		break;
958 	}
959 
960 	return 0;
961 }
962 
963 static struct notifier_block pm121_events = {
964 	.notifier_call	= pm121_notify,
965 };
966 
967 static int pm121_init_pm(void)
968 {
969 	const struct smu_sdbp_header *hdr;
970 
971 	hdr = smu_get_sdb_partition(SMU_SDB_SENSORTREE_ID, NULL);
972 	if (hdr != 0) {
973 		struct smu_sdbp_sensortree *st =
974 			(struct smu_sdbp_sensortree *)&hdr[1];
975 		pm121_mach_model = st->model_id;
976 	}
977 
978 	pm121_connection = &pm121_connections[pm121_mach_model - 2];
979 
980 	printk(KERN_INFO "pm121: Initializing for iMac G5 iSight model ID %d\n",
981 	       pm121_mach_model);
982 
983 	return 0;
984 }
985 
986 
987 static int pm121_probe(struct platform_device *ddev)
988 {
989 	wf_register_client(&pm121_events);
990 
991 	return 0;
992 }
993 
994 static int pm121_remove(struct platform_device *ddev)
995 {
996 	wf_unregister_client(&pm121_events);
997 	return 0;
998 }
999 
1000 static struct platform_driver pm121_driver = {
1001 	.probe = pm121_probe,
1002 	.remove = pm121_remove,
1003 	.driver = {
1004 		.name = "windfarm",
1005 		.bus = &platform_bus_type,
1006 	},
1007 };
1008 
1009 
1010 static int __init pm121_init(void)
1011 {
1012 	int rc = -ENODEV;
1013 
1014 	if (of_machine_is_compatible("PowerMac12,1"))
1015 		rc = pm121_init_pm();
1016 
1017 	if (rc == 0) {
1018 		request_module("windfarm_smu_controls");
1019 		request_module("windfarm_smu_sensors");
1020 		request_module("windfarm_smu_sat");
1021 		request_module("windfarm_lm75_sensor");
1022 		request_module("windfarm_max6690_sensor");
1023 		request_module("windfarm_cpufreq_clamp");
1024 		platform_driver_register(&pm121_driver);
1025 	}
1026 
1027 	return rc;
1028 }
1029 
1030 static void __exit pm121_exit(void)
1031 {
1032 
1033 	platform_driver_unregister(&pm121_driver);
1034 }
1035 
1036 
1037 module_init(pm121_init);
1038 module_exit(pm121_exit);
1039 
1040 MODULE_AUTHOR("Étienne Bersac <bersace@gmail.com>");
1041 MODULE_DESCRIPTION("Thermal control logic for iMac G5 (iSight)");
1042 MODULE_LICENSE("GPL");
1043 
1044