1 /*
2  * Windfarm PowerMac thermal control. iMac G5 iSight
3  *
4  * (c) Copyright 2007 Étienne Bersac <bersace@gmail.com>
5  *
6  * Bits & pieces from windfarm_pm81.c by (c) Copyright 2005 Benjamin
7  * Herrenschmidt, IBM Corp. <benh@kernel.crashing.org>
8  *
9  * Released under the term of the GNU GPL v2.
10  *
11  *
12  *
13  * PowerMac12,1
14  * ============
15  *
16  *
17  * The algorithm used is the PID control algorithm, used the same way
18  * the published Darwin code does, using the same values that are
19  * present in the Darwin 8.10 snapshot property lists (note however
20  * that none of the code has been re-used, it's a complete
21  * re-implementation
22  *
23  * There is two models using PowerMac12,1. Model 2 is iMac G5 iSight
24  * 17" while Model 3 is iMac G5 20". They do have both the same
25  * controls with a tiny difference. The control-ids of hard-drive-fan
26  * and cpu-fan is swapped.
27  *
28  *
29  * Target Correction :
30  *
31  * controls have a target correction calculated as :
32  *
33  * new_min = ((((average_power * slope) >> 16) + offset) >> 16) + min_value
34  * new_value = max(new_value, max(new_min, 0))
35  *
36  * OD Fan control correction.
37  *
38  * # model_id: 2
39  *   offset		: -19563152
40  *   slope		:  1956315
41  *
42  * # model_id: 3
43  *   offset		: -15650652
44  *   slope		:  1565065
45  *
46  * HD Fan control correction.
47  *
48  * # model_id: 2
49  *   offset		: -15650652
50  *   slope		:  1565065
51  *
52  * # model_id: 3
53  *   offset		: -19563152
54  *   slope		:  1956315
55  *
56  * CPU Fan control correction.
57  *
58  * # model_id: 2
59  *   offset		: -25431900
60  *   slope		:  2543190
61  *
62  * # model_id: 3
63  *   offset		: -15650652
64  *   slope		:  1565065
65  *
66  *
67  * Target rubber-banding :
68  *
69  * Some controls have a target correction which depends on another
70  * control value. The correction is computed in the following way :
71  *
72  * new_min = ref_value * slope + offset
73  *
74  * ref_value is the value of the reference control. If new_min is
75  * greater than 0, then we correct the target value using :
76  *
77  * new_target = max (new_target, new_min >> 16)
78  *
79  *
80  * # model_id : 2
81  *   control	: cpu-fan
82  *   ref	: optical-drive-fan
83  *   offset	: -15650652
84  *   slope	: 1565065
85  *
86  * # model_id : 3
87  *   control	: optical-drive-fan
88  *   ref	: hard-drive-fan
89  *   offset	: -32768000
90  *   slope	: 65536
91  *
92  *
93  * In order to have the moste efficient correction with those
94  * dependencies, we must trigger HD loop before OD loop before CPU
95  * loop.
96  *
97  *
98  * The various control loops found in Darwin config file are:
99  *
100  * HD Fan control loop.
101  *
102  * # model_id: 2
103  *   control        : hard-drive-fan
104  *   sensor         : hard-drive-temp
105  *   PID params     : G_d = 0x00000000
106  *                    G_p = 0x002D70A3
107  *                    G_r = 0x00019999
108  *                    History = 2 entries
109  *                    Input target = 0x370000
110  *                    Interval = 5s
111  *
112  * # model_id: 3
113  *   control        : hard-drive-fan
114  *   sensor         : hard-drive-temp
115  *   PID params     : G_d = 0x00000000
116  *                    G_p = 0x002170A3
117  *                    G_r = 0x00019999
118  *                    History = 2 entries
119  *                    Input target = 0x370000
120  *                    Interval = 5s
121  *
122  * OD Fan control loop.
123  *
124  * # model_id: 2
125  *   control        : optical-drive-fan
126  *   sensor         : optical-drive-temp
127  *   PID params     : G_d = 0x00000000
128  *                    G_p = 0x001FAE14
129  *                    G_r = 0x00019999
130  *                    History = 2 entries
131  *                    Input target = 0x320000
132  *                    Interval = 5s
133  *
134  * # model_id: 3
135  *   control        : optical-drive-fan
136  *   sensor         : optical-drive-temp
137  *   PID params     : G_d = 0x00000000
138  *                    G_p = 0x001FAE14
139  *                    G_r = 0x00019999
140  *                    History = 2 entries
141  *                    Input target = 0x320000
142  *                    Interval = 5s
143  *
144  * GPU Fan control loop.
145  *
146  * # model_id: 2
147  *   control        : hard-drive-fan
148  *   sensor         : gpu-temp
149  *   PID params     : G_d = 0x00000000
150  *                    G_p = 0x002A6666
151  *                    G_r = 0x00019999
152  *                    History = 2 entries
153  *                    Input target = 0x5A0000
154  *                    Interval = 5s
155  *
156  * # model_id: 3
157  *   control        : cpu-fan
158  *   sensor         : gpu-temp
159  *   PID params     : G_d = 0x00000000
160  *                    G_p = 0x0010CCCC
161  *                    G_r = 0x00019999
162  *                    History = 2 entries
163  *                    Input target = 0x500000
164  *                    Interval = 5s
165  *
166  * KODIAK (aka northbridge) Fan control loop.
167  *
168  * # model_id: 2
169  *   control        : optical-drive-fan
170  *   sensor         : north-bridge-temp
171  *   PID params     : G_d = 0x00000000
172  *                    G_p = 0x003BD70A
173  *                    G_r = 0x00019999
174  *                    History = 2 entries
175  *                    Input target = 0x550000
176  *                    Interval = 5s
177  *
178  * # model_id: 3
179  *   control        : hard-drive-fan
180  *   sensor         : north-bridge-temp
181  *   PID params     : G_d = 0x00000000
182  *                    G_p = 0x0030F5C2
183  *                    G_r = 0x00019999
184  *                    History = 2 entries
185  *                    Input target = 0x550000
186  *                    Interval = 5s
187  *
188  * CPU Fan control loop.
189  *
190  *   control        : cpu-fan
191  *   sensors        : cpu-temp, cpu-power
192  *   PID params     : from SDB partition
193  *
194  *
195  * CPU Slew control loop.
196  *
197  *   control        : cpufreq-clamp
198  *   sensor         : cpu-temp
199  *
200  */
201 
202 #undef	DEBUG
203 
204 #include <linux/types.h>
205 #include <linux/errno.h>
206 #include <linux/kernel.h>
207 #include <linux/delay.h>
208 #include <linux/slab.h>
209 #include <linux/init.h>
210 #include <linux/spinlock.h>
211 #include <linux/wait.h>
212 #include <linux/kmod.h>
213 #include <linux/device.h>
214 #include <linux/platform_device.h>
215 #include <asm/prom.h>
216 #include <asm/machdep.h>
217 #include <asm/io.h>
218 #include <asm/sections.h>
219 #include <asm/smu.h>
220 
221 #include "windfarm.h"
222 #include "windfarm_pid.h"
223 
224 #define VERSION "0.3"
225 
226 static int pm121_mach_model;	/* machine model id */
227 
228 /* Controls & sensors */
229 static struct wf_sensor	*sensor_cpu_power;
230 static struct wf_sensor	*sensor_cpu_temp;
231 static struct wf_sensor	*sensor_cpu_voltage;
232 static struct wf_sensor	*sensor_cpu_current;
233 static struct wf_sensor	*sensor_gpu_temp;
234 static struct wf_sensor	*sensor_north_bridge_temp;
235 static struct wf_sensor	*sensor_hard_drive_temp;
236 static struct wf_sensor	*sensor_optical_drive_temp;
237 static struct wf_sensor	*sensor_incoming_air_temp; /* unused ! */
238 
239 enum {
240 	FAN_CPU,
241 	FAN_HD,
242 	FAN_OD,
243 	CPUFREQ,
244 	N_CONTROLS
245 };
246 static struct wf_control *controls[N_CONTROLS] = {};
247 
248 /* Set to kick the control loop into life */
249 static int pm121_all_controls_ok, pm121_all_sensors_ok;
250 static bool pm121_started;
251 
252 enum {
253 	FAILURE_FAN		= 1 << 0,
254 	FAILURE_SENSOR		= 1 << 1,
255 	FAILURE_OVERTEMP	= 1 << 2
256 };
257 
258 /* All sys loops. Note the HD before the OD loop in order to have it
259    run before. */
260 enum {
261 	LOOP_GPU,		/* control = hd or cpu, but luckily,
262 				   it doesn't matter */
263 	LOOP_HD,		/* control = hd */
264 	LOOP_KODIAK,		/* control = hd or od */
265 	LOOP_OD,		/* control = od */
266 	N_LOOPS
267 };
268 
269 static const char *loop_names[N_LOOPS] = {
270 	"GPU",
271 	"HD",
272 	"KODIAK",
273 	"OD",
274 };
275 
276 #define	PM121_NUM_CONFIGS	2
277 
278 static unsigned int pm121_failure_state;
279 static int pm121_readjust, pm121_skipping;
280 static bool pm121_overtemp;
281 static s32 average_power;
282 
283 struct pm121_correction {
284 	int	offset;
285 	int	slope;
286 };
287 
288 static struct pm121_correction corrections[N_CONTROLS][PM121_NUM_CONFIGS] = {
289 	/* FAN_OD */
290 	{
291 		/* MODEL 2 */
292 		{ .offset	= -19563152,
293 		  .slope	=  1956315
294 		},
295 		/* MODEL 3 */
296 		{ .offset	= -15650652,
297 		  .slope	=  1565065
298 		},
299 	},
300 	/* FAN_HD */
301 	{
302 		/* MODEL 2 */
303 		{ .offset	= -15650652,
304 		  .slope	=  1565065
305 		},
306 		/* MODEL 3 */
307 		{ .offset	= -19563152,
308 		  .slope	=  1956315
309 		},
310 	},
311 	/* FAN_CPU */
312 	{
313 		/* MODEL 2 */
314 		{ .offset	= -25431900,
315 		  .slope	=  2543190
316 		},
317 		/* MODEL 3 */
318 		{ .offset	= -15650652,
319 		  .slope	=  1565065
320 		},
321 	},
322 	/* CPUFREQ has no correction (and is not implemented at all) */
323 };
324 
325 struct pm121_connection {
326 	unsigned int	control_id;
327 	unsigned int	ref_id;
328 	struct pm121_correction	correction;
329 };
330 
331 static struct pm121_connection pm121_connections[] = {
332 	/* MODEL 2 */
333 	{ .control_id	= FAN_CPU,
334 	  .ref_id	= FAN_OD,
335 	  { .offset	= -32768000,
336 	    .slope	=  65536
337 	  }
338 	},
339 	/* MODEL 3 */
340 	{ .control_id	= FAN_OD,
341 	  .ref_id	= FAN_HD,
342 	  { .offset	= -32768000,
343 	    .slope	=  65536
344 	  }
345 	},
346 };
347 
348 /* pointer to the current model connection */
349 static struct pm121_connection *pm121_connection;
350 
351 /*
352  * ****** System Fans Control Loop ******
353  *
354  */
355 
356 /* Since each loop handles only one control and we want to avoid
357  * writing virtual control, we store the control correction with the
358  * loop params. Some data are not set, there are common to all loop
359  * and thus, hardcoded.
360  */
361 struct pm121_sys_param {
362 	/* purely informative since we use mach_model-2 as index */
363 	int			model_id;
364 	struct wf_sensor	**sensor; /* use sensor_id instead ? */
365 	s32			gp, itarget;
366 	unsigned int		control_id;
367 };
368 
369 static struct pm121_sys_param
370 pm121_sys_all_params[N_LOOPS][PM121_NUM_CONFIGS] = {
371 	/* GPU Fan control loop */
372 	{
373 		{ .model_id	= 2,
374 		  .sensor	= &sensor_gpu_temp,
375 		  .gp		= 0x002A6666,
376 		  .itarget	= 0x5A0000,
377 		  .control_id	= FAN_HD,
378 		},
379 		{ .model_id	= 3,
380 		  .sensor	= &sensor_gpu_temp,
381 		  .gp		= 0x0010CCCC,
382 		  .itarget	= 0x500000,
383 		  .control_id	= FAN_CPU,
384 		},
385 	},
386 	/* HD Fan control loop */
387 	{
388 		{ .model_id	= 2,
389 		  .sensor	= &sensor_hard_drive_temp,
390 		  .gp		= 0x002D70A3,
391 		  .itarget	= 0x370000,
392 		  .control_id	= FAN_HD,
393 		},
394 		{ .model_id	= 3,
395 		  .sensor	= &sensor_hard_drive_temp,
396 		  .gp		= 0x002170A3,
397 		  .itarget	= 0x370000,
398 		  .control_id	= FAN_HD,
399 		},
400 	},
401 	/* KODIAK Fan control loop */
402 	{
403 		{ .model_id	= 2,
404 		  .sensor	= &sensor_north_bridge_temp,
405 		  .gp		= 0x003BD70A,
406 		  .itarget	= 0x550000,
407 		  .control_id	= FAN_OD,
408 		},
409 		{ .model_id	= 3,
410 		  .sensor	= &sensor_north_bridge_temp,
411 		  .gp		= 0x0030F5C2,
412 		  .itarget	= 0x550000,
413 		  .control_id	= FAN_HD,
414 		},
415 	},
416 	/* OD Fan control loop */
417 	{
418 		{ .model_id	= 2,
419 		  .sensor	= &sensor_optical_drive_temp,
420 		  .gp		= 0x001FAE14,
421 		  .itarget	= 0x320000,
422 		  .control_id	= FAN_OD,
423 		},
424 		{ .model_id	= 3,
425 		  .sensor	= &sensor_optical_drive_temp,
426 		  .gp		= 0x001FAE14,
427 		  .itarget	= 0x320000,
428 		  .control_id	= FAN_OD,
429 		},
430 	},
431 };
432 
433 /* the hardcoded values */
434 #define	PM121_SYS_GD		0x00000000
435 #define	PM121_SYS_GR		0x00019999
436 #define	PM121_SYS_HISTORY_SIZE	2
437 #define	PM121_SYS_INTERVAL	5
438 
439 /* State data used by the system fans control loop
440  */
441 struct pm121_sys_state {
442 	int			ticks;
443 	s32			setpoint;
444 	struct wf_pid_state	pid;
445 };
446 
447 struct pm121_sys_state *pm121_sys_state[N_LOOPS] = {};
448 
449 /*
450  * ****** CPU Fans Control Loop ******
451  *
452  */
453 
454 #define PM121_CPU_INTERVAL	1
455 
456 /* State data used by the cpu fans control loop
457  */
458 struct pm121_cpu_state {
459 	int			ticks;
460 	s32			setpoint;
461 	struct wf_cpu_pid_state	pid;
462 };
463 
464 static struct pm121_cpu_state *pm121_cpu_state;
465 
466 
467 
468 /*
469  * ***** Implementation *****
470  *
471  */
472 
473 /* correction the value using the output-low-bound correction algo */
474 static s32 pm121_correct(s32 new_setpoint,
475 			 unsigned int control_id,
476 			 s32 min)
477 {
478 	s32 new_min;
479 	struct pm121_correction *correction;
480 	correction = &corrections[control_id][pm121_mach_model - 2];
481 
482 	new_min = (average_power * correction->slope) >> 16;
483 	new_min += correction->offset;
484 	new_min = (new_min >> 16) + min;
485 
486 	return max3(new_setpoint, new_min, 0);
487 }
488 
489 static s32 pm121_connect(unsigned int control_id, s32 setpoint)
490 {
491 	s32 new_min, value, new_setpoint;
492 
493 	if (pm121_connection->control_id == control_id) {
494 		controls[control_id]->ops->get_value(controls[control_id],
495 						     &value);
496 		new_min = value * pm121_connection->correction.slope;
497 		new_min += pm121_connection->correction.offset;
498 		if (new_min > 0) {
499 			new_setpoint = max(setpoint, (new_min >> 16));
500 			if (new_setpoint != setpoint) {
501 				pr_debug("pm121: %s depending on %s, "
502 					 "corrected from %d to %d RPM\n",
503 					 controls[control_id]->name,
504 					 controls[pm121_connection->ref_id]->name,
505 					 (int) setpoint, (int) new_setpoint);
506 			}
507 		} else
508 			new_setpoint = setpoint;
509 	}
510 	/* no connection */
511 	else
512 		new_setpoint = setpoint;
513 
514 	return new_setpoint;
515 }
516 
517 /* FAN LOOPS */
518 static void pm121_create_sys_fans(int loop_id)
519 {
520 	struct pm121_sys_param *param = NULL;
521 	struct wf_pid_param pid_param;
522 	struct wf_control *control = NULL;
523 	int i;
524 
525 	/* First, locate the params for this model */
526 	for (i = 0; i < PM121_NUM_CONFIGS; i++) {
527 		if (pm121_sys_all_params[loop_id][i].model_id == pm121_mach_model) {
528 			param = &(pm121_sys_all_params[loop_id][i]);
529 			break;
530 		}
531 	}
532 
533 	/* No params found, put fans to max */
534 	if (param == NULL) {
535 		printk(KERN_WARNING "pm121: %s fan config not found "
536 		       " for this machine model\n",
537 		       loop_names[loop_id]);
538 		goto fail;
539 	}
540 
541 	control = controls[param->control_id];
542 
543 	/* Alloc & initialize state */
544 	pm121_sys_state[loop_id] = kmalloc(sizeof(struct pm121_sys_state),
545 					   GFP_KERNEL);
546 	if (pm121_sys_state[loop_id] == NULL) {
547 		printk(KERN_WARNING "pm121: Memory allocation error\n");
548 		goto fail;
549 	}
550 	pm121_sys_state[loop_id]->ticks = 1;
551 
552 	/* Fill PID params */
553 	pid_param.gd		= PM121_SYS_GD;
554 	pid_param.gp		= param->gp;
555 	pid_param.gr		= PM121_SYS_GR;
556 	pid_param.interval	= PM121_SYS_INTERVAL;
557 	pid_param.history_len	= PM121_SYS_HISTORY_SIZE;
558 	pid_param.itarget	= param->itarget;
559 	if(control)
560 	{
561 		pid_param.min		= control->ops->get_min(control);
562 		pid_param.max		= control->ops->get_max(control);
563 	} else {
564 		/*
565 		 * This is probably not the right!?
566 		 * Perhaps goto fail  if control == NULL  above?
567 		 */
568 		pid_param.min		= 0;
569 		pid_param.max		= 0;
570 	}
571 
572 	wf_pid_init(&pm121_sys_state[loop_id]->pid, &pid_param);
573 
574 	pr_debug("pm121: %s Fan control loop initialized.\n"
575 		 "       itarged=%d.%03d, min=%d RPM, max=%d RPM\n",
576 		 loop_names[loop_id], FIX32TOPRINT(pid_param.itarget),
577 		 pid_param.min, pid_param.max);
578 	return;
579 
580  fail:
581 	/* note that this is not optimal since another loop may still
582 	   control the same control */
583 	printk(KERN_WARNING "pm121: failed to set up %s loop "
584 	       "setting \"%s\" to max speed.\n",
585 	       loop_names[loop_id], control ? control->name : "uninitialized value");
586 
587 	if (control)
588 		wf_control_set_max(control);
589 }
590 
591 static void pm121_sys_fans_tick(int loop_id)
592 {
593 	struct pm121_sys_param *param;
594 	struct pm121_sys_state *st;
595 	struct wf_sensor *sensor;
596 	struct wf_control *control;
597 	s32 temp, new_setpoint;
598 	int rc;
599 
600 	param = &(pm121_sys_all_params[loop_id][pm121_mach_model-2]);
601 	st = pm121_sys_state[loop_id];
602 	sensor = *(param->sensor);
603 	control = controls[param->control_id];
604 
605 	if (--st->ticks != 0) {
606 		if (pm121_readjust)
607 			goto readjust;
608 		return;
609 	}
610 	st->ticks = PM121_SYS_INTERVAL;
611 
612 	rc = sensor->ops->get_value(sensor, &temp);
613 	if (rc) {
614 		printk(KERN_WARNING "windfarm: %s sensor error %d\n",
615 		       sensor->name, rc);
616 		pm121_failure_state |= FAILURE_SENSOR;
617 		return;
618 	}
619 
620 	pr_debug("pm121: %s Fan tick ! %s: %d.%03d\n",
621 		 loop_names[loop_id], sensor->name,
622 		 FIX32TOPRINT(temp));
623 
624 	new_setpoint = wf_pid_run(&st->pid, temp);
625 
626 	/* correction */
627 	new_setpoint = pm121_correct(new_setpoint,
628 				     param->control_id,
629 				     st->pid.param.min);
630 	/* linked corretion */
631 	new_setpoint = pm121_connect(param->control_id, new_setpoint);
632 
633 	if (new_setpoint == st->setpoint)
634 		return;
635 	st->setpoint = new_setpoint;
636 	pr_debug("pm121: %s corrected setpoint: %d RPM\n",
637 		 control->name, (int)new_setpoint);
638  readjust:
639 	if (control && pm121_failure_state == 0) {
640 		rc = control->ops->set_value(control, st->setpoint);
641 		if (rc) {
642 			printk(KERN_WARNING "windfarm: %s fan error %d\n",
643 			       control->name, rc);
644 			pm121_failure_state |= FAILURE_FAN;
645 		}
646 	}
647 }
648 
649 
650 /* CPU LOOP */
651 static void pm121_create_cpu_fans(void)
652 {
653 	struct wf_cpu_pid_param pid_param;
654 	const struct smu_sdbp_header *hdr;
655 	struct smu_sdbp_cpupiddata *piddata;
656 	struct smu_sdbp_fvt *fvt;
657 	struct wf_control *fan_cpu;
658 	s32 tmax, tdelta, maxpow, powadj;
659 
660 	fan_cpu = controls[FAN_CPU];
661 
662 	/* First, locate the PID params in SMU SBD */
663 	hdr = smu_get_sdb_partition(SMU_SDB_CPUPIDDATA_ID, NULL);
664 	if (hdr == 0) {
665 		printk(KERN_WARNING "pm121: CPU PID fan config not found.\n");
666 		goto fail;
667 	}
668 	piddata = (struct smu_sdbp_cpupiddata *)&hdr[1];
669 
670 	/* Get the FVT params for operating point 0 (the only supported one
671 	 * for now) in order to get tmax
672 	 */
673 	hdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL);
674 	if (hdr) {
675 		fvt = (struct smu_sdbp_fvt *)&hdr[1];
676 		tmax = ((s32)fvt->maxtemp) << 16;
677 	} else
678 		tmax = 0x5e0000; /* 94 degree default */
679 
680 	/* Alloc & initialize state */
681 	pm121_cpu_state = kmalloc(sizeof(struct pm121_cpu_state),
682 				  GFP_KERNEL);
683 	if (pm121_cpu_state == NULL)
684 		goto fail;
685 	pm121_cpu_state->ticks = 1;
686 
687 	/* Fill PID params */
688 	pid_param.interval = PM121_CPU_INTERVAL;
689 	pid_param.history_len = piddata->history_len;
690 	if (pid_param.history_len > WF_CPU_PID_MAX_HISTORY) {
691 		printk(KERN_WARNING "pm121: History size overflow on "
692 		       "CPU control loop (%d)\n", piddata->history_len);
693 		pid_param.history_len = WF_CPU_PID_MAX_HISTORY;
694 	}
695 	pid_param.gd = piddata->gd;
696 	pid_param.gp = piddata->gp;
697 	pid_param.gr = piddata->gr / pid_param.history_len;
698 
699 	tdelta = ((s32)piddata->target_temp_delta) << 16;
700 	maxpow = ((s32)piddata->max_power) << 16;
701 	powadj = ((s32)piddata->power_adj) << 16;
702 
703 	pid_param.tmax = tmax;
704 	pid_param.ttarget = tmax - tdelta;
705 	pid_param.pmaxadj = maxpow - powadj;
706 
707 	pid_param.min = fan_cpu->ops->get_min(fan_cpu);
708 	pid_param.max = fan_cpu->ops->get_max(fan_cpu);
709 
710 	wf_cpu_pid_init(&pm121_cpu_state->pid, &pid_param);
711 
712 	pr_debug("pm121: CPU Fan control initialized.\n");
713 	pr_debug("       ttarged=%d.%03d, tmax=%d.%03d, min=%d RPM, max=%d RPM,\n",
714 		 FIX32TOPRINT(pid_param.ttarget), FIX32TOPRINT(pid_param.tmax),
715 		 pid_param.min, pid_param.max);
716 
717 	return;
718 
719  fail:
720 	printk(KERN_WARNING "pm121: CPU fan config not found, max fan speed\n");
721 
722 	if (controls[CPUFREQ])
723 		wf_control_set_max(controls[CPUFREQ]);
724 	if (fan_cpu)
725 		wf_control_set_max(fan_cpu);
726 }
727 
728 
729 static void pm121_cpu_fans_tick(struct pm121_cpu_state *st)
730 {
731 	s32 new_setpoint, temp, power;
732 	struct wf_control *fan_cpu = NULL;
733 	int rc;
734 
735 	if (--st->ticks != 0) {
736 		if (pm121_readjust)
737 			goto readjust;
738 		return;
739 	}
740 	st->ticks = PM121_CPU_INTERVAL;
741 
742 	fan_cpu = controls[FAN_CPU];
743 
744 	rc = sensor_cpu_temp->ops->get_value(sensor_cpu_temp, &temp);
745 	if (rc) {
746 		printk(KERN_WARNING "pm121: CPU temp sensor error %d\n",
747 		       rc);
748 		pm121_failure_state |= FAILURE_SENSOR;
749 		return;
750 	}
751 
752 	rc = sensor_cpu_power->ops->get_value(sensor_cpu_power, &power);
753 	if (rc) {
754 		printk(KERN_WARNING "pm121: CPU power sensor error %d\n",
755 		       rc);
756 		pm121_failure_state |= FAILURE_SENSOR;
757 		return;
758 	}
759 
760 	pr_debug("pm121: CPU Fans tick ! CPU temp: %d.%03d°C, power: %d.%03d\n",
761 		 FIX32TOPRINT(temp), FIX32TOPRINT(power));
762 
763 	if (temp > st->pid.param.tmax)
764 		pm121_failure_state |= FAILURE_OVERTEMP;
765 
766 	new_setpoint = wf_cpu_pid_run(&st->pid, power, temp);
767 
768 	/* correction */
769 	new_setpoint = pm121_correct(new_setpoint,
770 				     FAN_CPU,
771 				     st->pid.param.min);
772 
773 	/* connected correction */
774 	new_setpoint = pm121_connect(FAN_CPU, new_setpoint);
775 
776 	if (st->setpoint == new_setpoint)
777 		return;
778 	st->setpoint = new_setpoint;
779 	pr_debug("pm121: CPU corrected setpoint: %d RPM\n", (int)new_setpoint);
780 
781  readjust:
782 	if (fan_cpu && pm121_failure_state == 0) {
783 		rc = fan_cpu->ops->set_value(fan_cpu, st->setpoint);
784 		if (rc) {
785 			printk(KERN_WARNING "pm121: %s fan error %d\n",
786 			       fan_cpu->name, rc);
787 			pm121_failure_state |= FAILURE_FAN;
788 		}
789 	}
790 }
791 
792 /*
793  * ****** Common ******
794  *
795  */
796 
797 static void pm121_tick(void)
798 {
799 	unsigned int last_failure = pm121_failure_state;
800 	unsigned int new_failure;
801 	s32 total_power;
802 	int i;
803 
804 	if (!pm121_started) {
805 		pr_debug("pm121: creating control loops !\n");
806 		for (i = 0; i < N_LOOPS; i++)
807 			pm121_create_sys_fans(i);
808 
809 		pm121_create_cpu_fans();
810 		pm121_started = true;
811 	}
812 
813 	/* skipping ticks */
814 	if (pm121_skipping && --pm121_skipping)
815 		return;
816 
817 	/* compute average power */
818 	total_power = 0;
819 	for (i = 0; i < pm121_cpu_state->pid.param.history_len; i++)
820 		total_power += pm121_cpu_state->pid.powers[i];
821 
822 	average_power = total_power / pm121_cpu_state->pid.param.history_len;
823 
824 
825 	pm121_failure_state = 0;
826 	for (i = 0 ; i < N_LOOPS; i++) {
827 		if (pm121_sys_state[i])
828 			pm121_sys_fans_tick(i);
829 	}
830 
831 	if (pm121_cpu_state)
832 		pm121_cpu_fans_tick(pm121_cpu_state);
833 
834 	pm121_readjust = 0;
835 	new_failure = pm121_failure_state & ~last_failure;
836 
837 	/* If entering failure mode, clamp cpufreq and ramp all
838 	 * fans to full speed.
839 	 */
840 	if (pm121_failure_state && !last_failure) {
841 		for (i = 0; i < N_CONTROLS; i++) {
842 			if (controls[i])
843 				wf_control_set_max(controls[i]);
844 		}
845 	}
846 
847 	/* If leaving failure mode, unclamp cpufreq and readjust
848 	 * all fans on next iteration
849 	 */
850 	if (!pm121_failure_state && last_failure) {
851 		if (controls[CPUFREQ])
852 			wf_control_set_min(controls[CPUFREQ]);
853 		pm121_readjust = 1;
854 	}
855 
856 	/* Overtemp condition detected, notify and start skipping a couple
857 	 * ticks to let the temperature go down
858 	 */
859 	if (new_failure & FAILURE_OVERTEMP) {
860 		wf_set_overtemp();
861 		pm121_skipping = 2;
862 		pm121_overtemp = true;
863 	}
864 
865 	/* We only clear the overtemp condition if overtemp is cleared
866 	 * _and_ no other failure is present. Since a sensor error will
867 	 * clear the overtemp condition (can't measure temperature) at
868 	 * the control loop levels, but we don't want to keep it clear
869 	 * here in this case
870 	 */
871 	if (!pm121_failure_state && pm121_overtemp) {
872 		wf_clear_overtemp();
873 		pm121_overtemp = false;
874 	}
875 }
876 
877 
878 static struct wf_control* pm121_register_control(struct wf_control *ct,
879 						 const char *match,
880 						 unsigned int id)
881 {
882 	if (controls[id] == NULL && !strcmp(ct->name, match)) {
883 		if (wf_get_control(ct) == 0)
884 			controls[id] = ct;
885 	}
886 	return controls[id];
887 }
888 
889 static void pm121_new_control(struct wf_control *ct)
890 {
891 	int all = 1;
892 
893 	if (pm121_all_controls_ok)
894 		return;
895 
896 	all = pm121_register_control(ct, "optical-drive-fan", FAN_OD) && all;
897 	all = pm121_register_control(ct, "hard-drive-fan", FAN_HD) && all;
898 	all = pm121_register_control(ct, "cpu-fan", FAN_CPU) && all;
899 	all = pm121_register_control(ct, "cpufreq-clamp", CPUFREQ) && all;
900 
901 	if (all)
902 		pm121_all_controls_ok = 1;
903 }
904 
905 
906 
907 
908 static struct wf_sensor* pm121_register_sensor(struct wf_sensor *sensor,
909 					       const char *match,
910 					       struct wf_sensor **var)
911 {
912 	if (*var == NULL && !strcmp(sensor->name, match)) {
913 		if (wf_get_sensor(sensor) == 0)
914 			*var = sensor;
915 	}
916 	return *var;
917 }
918 
919 static void pm121_new_sensor(struct wf_sensor *sr)
920 {
921 	int all = 1;
922 
923 	if (pm121_all_sensors_ok)
924 		return;
925 
926 	all = pm121_register_sensor(sr, "cpu-temp",
927 				    &sensor_cpu_temp) && all;
928 	all = pm121_register_sensor(sr, "cpu-current",
929 				    &sensor_cpu_current) && all;
930 	all = pm121_register_sensor(sr, "cpu-voltage",
931 				    &sensor_cpu_voltage) && all;
932 	all = pm121_register_sensor(sr, "cpu-power",
933 				    &sensor_cpu_power) && all;
934 	all = pm121_register_sensor(sr, "hard-drive-temp",
935 				    &sensor_hard_drive_temp) && all;
936 	all = pm121_register_sensor(sr, "optical-drive-temp",
937 				    &sensor_optical_drive_temp) && all;
938 	all = pm121_register_sensor(sr, "incoming-air-temp",
939 				    &sensor_incoming_air_temp) && all;
940 	all = pm121_register_sensor(sr, "north-bridge-temp",
941 				    &sensor_north_bridge_temp) && all;
942 	all = pm121_register_sensor(sr, "gpu-temp",
943 				    &sensor_gpu_temp) && all;
944 
945 	if (all)
946 		pm121_all_sensors_ok = 1;
947 }
948 
949 
950 
951 static int pm121_notify(struct notifier_block *self,
952 			unsigned long event, void *data)
953 {
954 	switch (event) {
955 	case WF_EVENT_NEW_CONTROL:
956 		pr_debug("pm121: new control %s detected\n",
957 			 ((struct wf_control *)data)->name);
958 		pm121_new_control(data);
959 		break;
960 	case WF_EVENT_NEW_SENSOR:
961 		pr_debug("pm121: new sensor %s detected\n",
962 			 ((struct wf_sensor *)data)->name);
963 		pm121_new_sensor(data);
964 		break;
965 	case WF_EVENT_TICK:
966 		if (pm121_all_controls_ok && pm121_all_sensors_ok)
967 			pm121_tick();
968 		break;
969 	}
970 
971 	return 0;
972 }
973 
974 static struct notifier_block pm121_events = {
975 	.notifier_call	= pm121_notify,
976 };
977 
978 static int pm121_init_pm(void)
979 {
980 	const struct smu_sdbp_header *hdr;
981 
982 	hdr = smu_get_sdb_partition(SMU_SDB_SENSORTREE_ID, NULL);
983 	if (hdr != 0) {
984 		struct smu_sdbp_sensortree *st =
985 			(struct smu_sdbp_sensortree *)&hdr[1];
986 		pm121_mach_model = st->model_id;
987 	}
988 
989 	pm121_connection = &pm121_connections[pm121_mach_model - 2];
990 
991 	printk(KERN_INFO "pm121: Initializing for iMac G5 iSight model ID %d\n",
992 	       pm121_mach_model);
993 
994 	return 0;
995 }
996 
997 
998 static int pm121_probe(struct platform_device *ddev)
999 {
1000 	wf_register_client(&pm121_events);
1001 
1002 	return 0;
1003 }
1004 
1005 static int pm121_remove(struct platform_device *ddev)
1006 {
1007 	wf_unregister_client(&pm121_events);
1008 	return 0;
1009 }
1010 
1011 static struct platform_driver pm121_driver = {
1012 	.probe = pm121_probe,
1013 	.remove = pm121_remove,
1014 	.driver = {
1015 		.name = "windfarm",
1016 		.bus = &platform_bus_type,
1017 	},
1018 };
1019 
1020 
1021 static int __init pm121_init(void)
1022 {
1023 	int rc = -ENODEV;
1024 
1025 	if (of_machine_is_compatible("PowerMac12,1"))
1026 		rc = pm121_init_pm();
1027 
1028 	if (rc == 0) {
1029 		request_module("windfarm_smu_controls");
1030 		request_module("windfarm_smu_sensors");
1031 		request_module("windfarm_smu_sat");
1032 		request_module("windfarm_lm75_sensor");
1033 		request_module("windfarm_max6690_sensor");
1034 		request_module("windfarm_cpufreq_clamp");
1035 		platform_driver_register(&pm121_driver);
1036 	}
1037 
1038 	return rc;
1039 }
1040 
1041 static void __exit pm121_exit(void)
1042 {
1043 
1044 	platform_driver_unregister(&pm121_driver);
1045 }
1046 
1047 
1048 module_init(pm121_init);
1049 module_exit(pm121_exit);
1050 
1051 MODULE_AUTHOR("Étienne Bersac <bersace@gmail.com>");
1052 MODULE_DESCRIPTION("Thermal control logic for iMac G5 (iSight)");
1053 MODULE_LICENSE("GPL");
1054 
1055