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, pm121_started;
250 
251 enum {
252 	FAILURE_FAN		= 1 << 0,
253 	FAILURE_SENSOR		= 1 << 1,
254 	FAILURE_OVERTEMP	= 1 << 2
255 };
256 
257 /* All sys loops. Note the HD before the OD loop in order to have it
258    run before. */
259 enum {
260 	LOOP_GPU,		/* control = hd or cpu, but luckily,
261 				   it doesn't matter */
262 	LOOP_HD,		/* control = hd */
263 	LOOP_KODIAK,		/* control = hd or od */
264 	LOOP_OD,		/* control = od */
265 	N_LOOPS
266 };
267 
268 static const char *loop_names[N_LOOPS] = {
269 	"GPU",
270 	"HD",
271 	"KODIAK",
272 	"OD",
273 };
274 
275 #define	PM121_NUM_CONFIGS	2
276 
277 static unsigned int pm121_failure_state;
278 static int pm121_readjust, pm121_skipping;
279 static bool pm121_overtemp;
280 static s32 average_power;
281 
282 struct pm121_correction {
283 	int	offset;
284 	int	slope;
285 };
286 
287 static struct pm121_correction corrections[N_CONTROLS][PM121_NUM_CONFIGS] = {
288 	/* FAN_OD */
289 	{
290 		/* MODEL 2 */
291 		{ .offset	= -19563152,
292 		  .slope	=  1956315
293 		},
294 		/* MODEL 3 */
295 		{ .offset	= -15650652,
296 		  .slope	=  1565065
297 		},
298 	},
299 	/* FAN_HD */
300 	{
301 		/* MODEL 2 */
302 		{ .offset	= -15650652,
303 		  .slope	=  1565065
304 		},
305 		/* MODEL 3 */
306 		{ .offset	= -19563152,
307 		  .slope	=  1956315
308 		},
309 	},
310 	/* FAN_CPU */
311 	{
312 		/* MODEL 2 */
313 		{ .offset	= -25431900,
314 		  .slope	=  2543190
315 		},
316 		/* MODEL 3 */
317 		{ .offset	= -15650652,
318 		  .slope	=  1565065
319 		},
320 	},
321 	/* CPUFREQ has no correction (and is not implemented at all) */
322 };
323 
324 struct pm121_connection {
325 	unsigned int	control_id;
326 	unsigned int	ref_id;
327 	struct pm121_correction	correction;
328 };
329 
330 static struct pm121_connection pm121_connections[] = {
331 	/* MODEL 2 */
332 	{ .control_id	= FAN_CPU,
333 	  .ref_id	= FAN_OD,
334 	  { .offset	= -32768000,
335 	    .slope	=  65536
336 	  }
337 	},
338 	/* MODEL 3 */
339 	{ .control_id	= FAN_OD,
340 	  .ref_id	= FAN_HD,
341 	  { .offset	= -32768000,
342 	    .slope	=  65536
343 	  }
344 	},
345 };
346 
347 /* pointer to the current model connection */
348 static struct pm121_connection *pm121_connection;
349 
350 /*
351  * ****** System Fans Control Loop ******
352  *
353  */
354 
355 /* Since each loop handles only one control and we want to avoid
356  * writing virtual control, we store the control correction with the
357  * loop params. Some data are not set, there are common to all loop
358  * and thus, hardcoded.
359  */
360 struct pm121_sys_param {
361 	/* purely informative since we use mach_model-2 as index */
362 	int			model_id;
363 	struct wf_sensor	**sensor; /* use sensor_id instead ? */
364 	s32			gp, itarget;
365 	unsigned int		control_id;
366 };
367 
368 static struct pm121_sys_param
369 pm121_sys_all_params[N_LOOPS][PM121_NUM_CONFIGS] = {
370 	/* GPU Fan control loop */
371 	{
372 		{ .model_id	= 2,
373 		  .sensor	= &sensor_gpu_temp,
374 		  .gp		= 0x002A6666,
375 		  .itarget	= 0x5A0000,
376 		  .control_id	= FAN_HD,
377 		},
378 		{ .model_id	= 3,
379 		  .sensor	= &sensor_gpu_temp,
380 		  .gp		= 0x0010CCCC,
381 		  .itarget	= 0x500000,
382 		  .control_id	= FAN_CPU,
383 		},
384 	},
385 	/* HD Fan control loop */
386 	{
387 		{ .model_id	= 2,
388 		  .sensor	= &sensor_hard_drive_temp,
389 		  .gp		= 0x002D70A3,
390 		  .itarget	= 0x370000,
391 		  .control_id	= FAN_HD,
392 		},
393 		{ .model_id	= 3,
394 		  .sensor	= &sensor_hard_drive_temp,
395 		  .gp		= 0x002170A3,
396 		  .itarget	= 0x370000,
397 		  .control_id	= FAN_HD,
398 		},
399 	},
400 	/* KODIAK Fan control loop */
401 	{
402 		{ .model_id	= 2,
403 		  .sensor	= &sensor_north_bridge_temp,
404 		  .gp		= 0x003BD70A,
405 		  .itarget	= 0x550000,
406 		  .control_id	= FAN_OD,
407 		},
408 		{ .model_id	= 3,
409 		  .sensor	= &sensor_north_bridge_temp,
410 		  .gp		= 0x0030F5C2,
411 		  .itarget	= 0x550000,
412 		  .control_id	= FAN_HD,
413 		},
414 	},
415 	/* OD Fan control loop */
416 	{
417 		{ .model_id	= 2,
418 		  .sensor	= &sensor_optical_drive_temp,
419 		  .gp		= 0x001FAE14,
420 		  .itarget	= 0x320000,
421 		  .control_id	= FAN_OD,
422 		},
423 		{ .model_id	= 3,
424 		  .sensor	= &sensor_optical_drive_temp,
425 		  .gp		= 0x001FAE14,
426 		  .itarget	= 0x320000,
427 		  .control_id	= FAN_OD,
428 		},
429 	},
430 };
431 
432 /* the hardcoded values */
433 #define	PM121_SYS_GD		0x00000000
434 #define	PM121_SYS_GR		0x00019999
435 #define	PM121_SYS_HISTORY_SIZE	2
436 #define	PM121_SYS_INTERVAL	5
437 
438 /* State data used by the system fans control loop
439  */
440 struct pm121_sys_state {
441 	int			ticks;
442 	s32			setpoint;
443 	struct wf_pid_state	pid;
444 };
445 
446 struct pm121_sys_state *pm121_sys_state[N_LOOPS] = {};
447 
448 /*
449  * ****** CPU Fans Control Loop ******
450  *
451  */
452 
453 #define PM121_CPU_INTERVAL	1
454 
455 /* State data used by the cpu fans control loop
456  */
457 struct pm121_cpu_state {
458 	int			ticks;
459 	s32			setpoint;
460 	struct wf_cpu_pid_state	pid;
461 };
462 
463 static struct pm121_cpu_state *pm121_cpu_state;
464 
465 
466 
467 /*
468  * ***** Implementation *****
469  *
470  */
471 
472 /* correction the value using the output-low-bound correction algo */
473 static s32 pm121_correct(s32 new_setpoint,
474 			 unsigned int control_id,
475 			 s32 min)
476 {
477 	s32 new_min;
478 	struct pm121_correction *correction;
479 	correction = &corrections[control_id][pm121_mach_model - 2];
480 
481 	new_min = (average_power * correction->slope) >> 16;
482 	new_min += correction->offset;
483 	new_min = (new_min >> 16) + min;
484 
485 	return max3(new_setpoint, new_min, 0);
486 }
487 
488 static s32 pm121_connect(unsigned int control_id, s32 setpoint)
489 {
490 	s32 new_min, value, new_setpoint;
491 
492 	if (pm121_connection->control_id == control_id) {
493 		controls[control_id]->ops->get_value(controls[control_id],
494 						     &value);
495 		new_min = value * pm121_connection->correction.slope;
496 		new_min += pm121_connection->correction.offset;
497 		if (new_min > 0) {
498 			new_setpoint = max(setpoint, (new_min >> 16));
499 			if (new_setpoint != setpoint) {
500 				pr_debug("pm121: %s depending on %s, "
501 					 "corrected from %d to %d RPM\n",
502 					 controls[control_id]->name,
503 					 controls[pm121_connection->ref_id]->name,
504 					 (int) setpoint, (int) new_setpoint);
505 			}
506 		} else
507 			new_setpoint = setpoint;
508 	}
509 	/* no connection */
510 	else
511 		new_setpoint = setpoint;
512 
513 	return new_setpoint;
514 }
515 
516 /* FAN LOOPS */
517 static void pm121_create_sys_fans(int loop_id)
518 {
519 	struct pm121_sys_param *param = NULL;
520 	struct wf_pid_param pid_param;
521 	struct wf_control *control = NULL;
522 	int i;
523 
524 	/* First, locate the params for this model */
525 	for (i = 0; i < PM121_NUM_CONFIGS; i++) {
526 		if (pm121_sys_all_params[loop_id][i].model_id == pm121_mach_model) {
527 			param = &(pm121_sys_all_params[loop_id][i]);
528 			break;
529 		}
530 	}
531 
532 	/* No params found, put fans to max */
533 	if (param == NULL) {
534 		printk(KERN_WARNING "pm121: %s fan config not found "
535 		       " for this machine model\n",
536 		       loop_names[loop_id]);
537 		goto fail;
538 	}
539 
540 	control = controls[param->control_id];
541 
542 	/* Alloc & initialize state */
543 	pm121_sys_state[loop_id] = kmalloc(sizeof(struct pm121_sys_state),
544 					   GFP_KERNEL);
545 	if (pm121_sys_state[loop_id] == NULL) {
546 		printk(KERN_WARNING "pm121: Memory allocation error\n");
547 		goto fail;
548 	}
549 	pm121_sys_state[loop_id]->ticks = 1;
550 
551 	/* Fill PID params */
552 	pid_param.gd		= PM121_SYS_GD;
553 	pid_param.gp		= param->gp;
554 	pid_param.gr		= PM121_SYS_GR;
555 	pid_param.interval	= PM121_SYS_INTERVAL;
556 	pid_param.history_len	= PM121_SYS_HISTORY_SIZE;
557 	pid_param.itarget	= param->itarget;
558 	pid_param.min		= control->ops->get_min(control);
559 	pid_param.max		= control->ops->get_max(control);
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->name);
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("       ttarged=%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 = 1;
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