2 * Windfarm PowerMac thermal control. SMU based 1 CPU desktop control loops
4 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
5 * <benh@kernel.crashing.org>
7 * Released under the term of the GNU GPL v2.
9 * The algorithm used is the PID control algorithm, used the same
10 * way the published Darwin code does, using the same values that
11 * are present in the Darwin 8.2 snapshot property lists (note however
12 * that none of the code has been re-used, it's a complete re-implementation
14 * The various control loops found in Darwin config file are:
19 * Has 3 control loops: CPU fans is similar to PowerMac8,1 (though it doesn't
20 * try to play with other control loops fans). Drive bay is rather basic PID
21 * with one sensor and one fan. Slots area is a bit different as the Darwin
22 * driver is supposed to be capable of working in a special "AGP" mode which
23 * involves the presence of an AGP sensor and an AGP fan (possibly on the
24 * AGP card itself). I can't deal with that special mode as I don't have
25 * access to those additional sensor/fans for now (though ultimately, it would
26 * be possible to add sensor objects for them) so I'm only implementing the
27 * basic PCI slot control loop
30 #include <linux/types.h>
31 #include <linux/errno.h>
32 #include <linux/kernel.h>
33 #include <linux/delay.h>
34 #include <linux/slab.h>
35 #include <linux/init.h>
36 #include <linux/spinlock.h>
37 #include <linux/wait.h>
38 #include <linux/kmod.h>
39 #include <linux/device.h>
40 #include <linux/platform_device.h>
42 #include <asm/machdep.h>
44 #include <asm/system.h>
45 #include <asm/sections.h>
49 #include "windfarm_pid.h"
56 #define DBG(args...) printk(args)
58 #define DBG(args...) do { } while(0)
61 /* define this to force CPU overtemp to 74 degree, useful for testing
64 #undef HACKED_OVERTEMP
66 /* Controls & sensors */
67 static struct wf_sensor
*sensor_cpu_power
;
68 static struct wf_sensor
*sensor_cpu_temp
;
69 static struct wf_sensor
*sensor_hd_temp
;
70 static struct wf_sensor
*sensor_slots_power
;
71 static struct wf_control
*fan_cpu_main
;
72 static struct wf_control
*fan_cpu_second
;
73 static struct wf_control
*fan_cpu_third
;
74 static struct wf_control
*fan_hd
;
75 static struct wf_control
*fan_slots
;
76 static struct wf_control
*cpufreq_clamp
;
78 /* Set to kick the control loop into life */
79 static int wf_smu_all_controls_ok
, wf_smu_all_sensors_ok
, wf_smu_started
;
81 /* Failure handling.. could be nicer */
82 #define FAILURE_FAN 0x01
83 #define FAILURE_SENSOR 0x02
84 #define FAILURE_OVERTEMP 0x04
86 static unsigned int wf_smu_failure_state
;
87 static int wf_smu_readjust
, wf_smu_skipping
;
90 * ****** CPU Fans Control Loop ******
95 #define WF_SMU_CPU_FANS_INTERVAL 1
96 #define WF_SMU_CPU_FANS_MAX_HISTORY 16
98 /* State data used by the cpu fans control loop
100 struct wf_smu_cpu_fans_state
{
103 struct wf_cpu_pid_state pid
;
106 static struct wf_smu_cpu_fans_state
*wf_smu_cpu_fans
;
111 * ****** Drive Fan Control Loop ******
115 struct wf_smu_drive_fans_state
{
118 struct wf_pid_state pid
;
121 static struct wf_smu_drive_fans_state
*wf_smu_drive_fans
;
124 * ****** Slots Fan Control Loop ******
128 struct wf_smu_slots_fans_state
{
131 struct wf_pid_state pid
;
134 static struct wf_smu_slots_fans_state
*wf_smu_slots_fans
;
137 * ***** Implementation *****
142 static void wf_smu_create_cpu_fans(void)
144 struct wf_cpu_pid_param pid_param
;
145 const struct smu_sdbp_header
*hdr
;
146 struct smu_sdbp_cpupiddata
*piddata
;
147 struct smu_sdbp_fvt
*fvt
;
148 s32 tmax
, tdelta
, maxpow
, powadj
;
150 /* First, locate the PID params in SMU SBD */
151 hdr
= smu_get_sdb_partition(SMU_SDB_CPUPIDDATA_ID
, NULL
);
153 printk(KERN_WARNING
"windfarm: CPU PID fan config not found "
157 piddata
= (struct smu_sdbp_cpupiddata
*)&hdr
[1];
159 /* Get the FVT params for operating point 0 (the only supported one
160 * for now) in order to get tmax
162 hdr
= smu_get_sdb_partition(SMU_SDB_FVT_ID
, NULL
);
164 fvt
= (struct smu_sdbp_fvt
*)&hdr
[1];
165 tmax
= ((s32
)fvt
->maxtemp
) << 16;
167 tmax
= 0x5e0000; /* 94 degree default */
169 /* Alloc & initialize state */
170 wf_smu_cpu_fans
= kmalloc(sizeof(struct wf_smu_cpu_fans_state
),
172 if (wf_smu_cpu_fans
== NULL
)
174 wf_smu_cpu_fans
->ticks
= 1;
176 /* Fill PID params */
177 pid_param
.interval
= WF_SMU_CPU_FANS_INTERVAL
;
178 pid_param
.history_len
= piddata
->history_len
;
179 if (pid_param
.history_len
> WF_CPU_PID_MAX_HISTORY
) {
180 printk(KERN_WARNING
"windfarm: History size overflow on "
181 "CPU control loop (%d)\n", piddata
->history_len
);
182 pid_param
.history_len
= WF_CPU_PID_MAX_HISTORY
;
184 pid_param
.gd
= piddata
->gd
;
185 pid_param
.gp
= piddata
->gp
;
186 pid_param
.gr
= piddata
->gr
/ pid_param
.history_len
;
188 tdelta
= ((s32
)piddata
->target_temp_delta
) << 16;
189 maxpow
= ((s32
)piddata
->max_power
) << 16;
190 powadj
= ((s32
)piddata
->power_adj
) << 16;
192 pid_param
.tmax
= tmax
;
193 pid_param
.ttarget
= tmax
- tdelta
;
194 pid_param
.pmaxadj
= maxpow
- powadj
;
196 pid_param
.min
= fan_cpu_main
->ops
->get_min(fan_cpu_main
);
197 pid_param
.max
= fan_cpu_main
->ops
->get_max(fan_cpu_main
);
199 wf_cpu_pid_init(&wf_smu_cpu_fans
->pid
, &pid_param
);
201 DBG("wf: CPU Fan control initialized.\n");
202 DBG(" ttarged=%d.%03d, tmax=%d.%03d, min=%d RPM, max=%d RPM\n",
203 FIX32TOPRINT(pid_param
.ttarget
), FIX32TOPRINT(pid_param
.tmax
),
204 pid_param
.min
, pid_param
.max
);
209 printk(KERN_WARNING
"windfarm: CPU fan config not found\n"
210 "for this machine model, max fan speed\n");
213 wf_control_set_max(cpufreq_clamp
);
215 wf_control_set_max(fan_cpu_main
);
218 static void wf_smu_cpu_fans_tick(struct wf_smu_cpu_fans_state
*st
)
220 s32 new_setpoint
, temp
, power
;
223 if (--st
->ticks
!= 0) {
228 st
->ticks
= WF_SMU_CPU_FANS_INTERVAL
;
230 rc
= sensor_cpu_temp
->ops
->get_value(sensor_cpu_temp
, &temp
);
232 printk(KERN_WARNING
"windfarm: CPU temp sensor error %d\n",
234 wf_smu_failure_state
|= FAILURE_SENSOR
;
238 rc
= sensor_cpu_power
->ops
->get_value(sensor_cpu_power
, &power
);
240 printk(KERN_WARNING
"windfarm: CPU power sensor error %d\n",
242 wf_smu_failure_state
|= FAILURE_SENSOR
;
246 DBG("wf_smu: CPU Fans tick ! CPU temp: %d.%03d, power: %d.%03d\n",
247 FIX32TOPRINT(temp
), FIX32TOPRINT(power
));
249 #ifdef HACKED_OVERTEMP
251 wf_smu_failure_state
|= FAILURE_OVERTEMP
;
253 if (temp
> st
->pid
.param
.tmax
)
254 wf_smu_failure_state
|= FAILURE_OVERTEMP
;
256 new_setpoint
= wf_cpu_pid_run(&st
->pid
, power
, temp
);
258 DBG("wf_smu: new_setpoint: %d RPM\n", (int)new_setpoint
);
260 if (st
->cpu_setpoint
== new_setpoint
)
262 st
->cpu_setpoint
= new_setpoint
;
264 if (fan_cpu_main
&& wf_smu_failure_state
== 0) {
265 rc
= fan_cpu_main
->ops
->set_value(fan_cpu_main
,
268 printk(KERN_WARNING
"windfarm: CPU main fan"
270 wf_smu_failure_state
|= FAILURE_FAN
;
273 if (fan_cpu_second
&& wf_smu_failure_state
== 0) {
274 rc
= fan_cpu_second
->ops
->set_value(fan_cpu_second
,
277 printk(KERN_WARNING
"windfarm: CPU second fan"
279 wf_smu_failure_state
|= FAILURE_FAN
;
282 if (fan_cpu_third
&& wf_smu_failure_state
== 0) {
283 rc
= fan_cpu_main
->ops
->set_value(fan_cpu_third
,
286 printk(KERN_WARNING
"windfarm: CPU third fan"
288 wf_smu_failure_state
|= FAILURE_FAN
;
293 static void wf_smu_create_drive_fans(void)
295 struct wf_pid_param param
= {
301 .itarget
= 0x00200000,
304 /* Alloc & initialize state */
305 wf_smu_drive_fans
= kmalloc(sizeof(struct wf_smu_drive_fans_state
),
307 if (wf_smu_drive_fans
== NULL
) {
308 printk(KERN_WARNING
"windfarm: Memory allocation error"
312 wf_smu_drive_fans
->ticks
= 1;
314 /* Fill PID params */
315 param
.additive
= (fan_hd
->type
== WF_CONTROL_RPM_FAN
);
316 param
.min
= fan_hd
->ops
->get_min(fan_hd
);
317 param
.max
= fan_hd
->ops
->get_max(fan_hd
);
318 wf_pid_init(&wf_smu_drive_fans
->pid
, ¶m
);
320 DBG("wf: Drive Fan control initialized.\n");
321 DBG(" itarged=%d.%03d, min=%d RPM, max=%d RPM\n",
322 FIX32TOPRINT(param
.itarget
), param
.min
, param
.max
);
327 wf_control_set_max(fan_hd
);
330 static void wf_smu_drive_fans_tick(struct wf_smu_drive_fans_state
*st
)
332 s32 new_setpoint
, temp
;
335 if (--st
->ticks
!= 0) {
340 st
->ticks
= st
->pid
.param
.interval
;
342 rc
= sensor_hd_temp
->ops
->get_value(sensor_hd_temp
, &temp
);
344 printk(KERN_WARNING
"windfarm: HD temp sensor error %d\n",
346 wf_smu_failure_state
|= FAILURE_SENSOR
;
350 DBG("wf_smu: Drive Fans tick ! HD temp: %d.%03d\n",
353 if (temp
> (st
->pid
.param
.itarget
+ 0x50000))
354 wf_smu_failure_state
|= FAILURE_OVERTEMP
;
356 new_setpoint
= wf_pid_run(&st
->pid
, temp
);
358 DBG("wf_smu: new_setpoint: %d\n", (int)new_setpoint
);
360 if (st
->setpoint
== new_setpoint
)
362 st
->setpoint
= new_setpoint
;
364 if (fan_hd
&& wf_smu_failure_state
== 0) {
365 rc
= fan_hd
->ops
->set_value(fan_hd
, st
->setpoint
);
367 printk(KERN_WARNING
"windfarm: HD fan error %d\n",
369 wf_smu_failure_state
|= FAILURE_FAN
;
374 static void wf_smu_create_slots_fans(void)
376 struct wf_pid_param param
= {
382 .itarget
= 0x00000000
385 /* Alloc & initialize state */
386 wf_smu_slots_fans
= kmalloc(sizeof(struct wf_smu_slots_fans_state
),
388 if (wf_smu_slots_fans
== NULL
) {
389 printk(KERN_WARNING
"windfarm: Memory allocation error"
393 wf_smu_slots_fans
->ticks
= 1;
395 /* Fill PID params */
396 param
.additive
= (fan_slots
->type
== WF_CONTROL_RPM_FAN
);
397 param
.min
= fan_slots
->ops
->get_min(fan_slots
);
398 param
.max
= fan_slots
->ops
->get_max(fan_slots
);
399 wf_pid_init(&wf_smu_slots_fans
->pid
, ¶m
);
401 DBG("wf: Slots Fan control initialized.\n");
402 DBG(" itarged=%d.%03d, min=%d RPM, max=%d RPM\n",
403 FIX32TOPRINT(param
.itarget
), param
.min
, param
.max
);
408 wf_control_set_max(fan_slots
);
411 static void wf_smu_slots_fans_tick(struct wf_smu_slots_fans_state
*st
)
413 s32 new_setpoint
, power
;
416 if (--st
->ticks
!= 0) {
421 st
->ticks
= st
->pid
.param
.interval
;
423 rc
= sensor_slots_power
->ops
->get_value(sensor_slots_power
, &power
);
425 printk(KERN_WARNING
"windfarm: Slots power sensor error %d\n",
427 wf_smu_failure_state
|= FAILURE_SENSOR
;
431 DBG("wf_smu: Slots Fans tick ! Slots power: %d.%03d\n",
432 FIX32TOPRINT(power
));
434 #if 0 /* Check what makes a good overtemp condition */
435 if (power
> (st
->pid
.param
.itarget
+ 0x50000))
436 wf_smu_failure_state
|= FAILURE_OVERTEMP
;
439 new_setpoint
= wf_pid_run(&st
->pid
, power
);
441 DBG("wf_smu: new_setpoint: %d\n", (int)new_setpoint
);
443 if (st
->setpoint
== new_setpoint
)
445 st
->setpoint
= new_setpoint
;
447 if (fan_slots
&& wf_smu_failure_state
== 0) {
448 rc
= fan_slots
->ops
->set_value(fan_slots
, st
->setpoint
);
450 printk(KERN_WARNING
"windfarm: Slots fan error %d\n",
452 wf_smu_failure_state
|= FAILURE_FAN
;
459 * ****** Setup / Init / Misc ... ******
463 static void wf_smu_tick(void)
465 unsigned int last_failure
= wf_smu_failure_state
;
466 unsigned int new_failure
;
468 if (!wf_smu_started
) {
469 DBG("wf: creating control loops !\n");
470 wf_smu_create_drive_fans();
471 wf_smu_create_slots_fans();
472 wf_smu_create_cpu_fans();
477 if (wf_smu_skipping
&& --wf_smu_skipping
)
480 wf_smu_failure_state
= 0;
481 if (wf_smu_drive_fans
)
482 wf_smu_drive_fans_tick(wf_smu_drive_fans
);
483 if (wf_smu_slots_fans
)
484 wf_smu_slots_fans_tick(wf_smu_slots_fans
);
486 wf_smu_cpu_fans_tick(wf_smu_cpu_fans
);
489 new_failure
= wf_smu_failure_state
& ~last_failure
;
491 /* If entering failure mode, clamp cpufreq and ramp all
492 * fans to full speed.
494 if (wf_smu_failure_state
&& !last_failure
) {
496 wf_control_set_max(cpufreq_clamp
);
498 wf_control_set_max(fan_cpu_main
);
500 wf_control_set_max(fan_cpu_second
);
502 wf_control_set_max(fan_cpu_third
);
504 wf_control_set_max(fan_hd
);
506 wf_control_set_max(fan_slots
);
509 /* If leaving failure mode, unclamp cpufreq and readjust
510 * all fans on next iteration
512 if (!wf_smu_failure_state
&& last_failure
) {
514 wf_control_set_min(cpufreq_clamp
);
518 /* Overtemp condition detected, notify and start skipping a couple
519 * ticks to let the temperature go down
521 if (new_failure
& FAILURE_OVERTEMP
) {
526 /* We only clear the overtemp condition if overtemp is cleared
527 * _and_ no other failure is present. Since a sensor error will
528 * clear the overtemp condition (can't measure temperature) at
529 * the control loop levels, but we don't want to keep it clear
532 if (new_failure
== 0 && last_failure
& FAILURE_OVERTEMP
)
537 static void wf_smu_new_control(struct wf_control
*ct
)
539 if (wf_smu_all_controls_ok
)
542 if (fan_cpu_main
== NULL
&& !strcmp(ct
->name
, "cpu-rear-fan-0")) {
543 if (wf_get_control(ct
) == 0)
547 if (fan_cpu_second
== NULL
&& !strcmp(ct
->name
, "cpu-rear-fan-1")) {
548 if (wf_get_control(ct
) == 0)
552 if (fan_cpu_third
== NULL
&& !strcmp(ct
->name
, "cpu-front-fan-0")) {
553 if (wf_get_control(ct
) == 0)
557 if (cpufreq_clamp
== NULL
&& !strcmp(ct
->name
, "cpufreq-clamp")) {
558 if (wf_get_control(ct
) == 0)
562 if (fan_hd
== NULL
&& !strcmp(ct
->name
, "drive-bay-fan")) {
563 if (wf_get_control(ct
) == 0)
567 if (fan_slots
== NULL
&& !strcmp(ct
->name
, "slots-fan")) {
568 if (wf_get_control(ct
) == 0)
572 if (fan_cpu_main
&& (fan_cpu_second
|| fan_cpu_third
) && fan_hd
&&
573 fan_slots
&& cpufreq_clamp
)
574 wf_smu_all_controls_ok
= 1;
577 static void wf_smu_new_sensor(struct wf_sensor
*sr
)
579 if (wf_smu_all_sensors_ok
)
582 if (sensor_cpu_power
== NULL
&& !strcmp(sr
->name
, "cpu-power")) {
583 if (wf_get_sensor(sr
) == 0)
584 sensor_cpu_power
= sr
;
587 if (sensor_cpu_temp
== NULL
&& !strcmp(sr
->name
, "cpu-temp")) {
588 if (wf_get_sensor(sr
) == 0)
589 sensor_cpu_temp
= sr
;
592 if (sensor_hd_temp
== NULL
&& !strcmp(sr
->name
, "hd-temp")) {
593 if (wf_get_sensor(sr
) == 0)
597 if (sensor_slots_power
== NULL
&& !strcmp(sr
->name
, "slots-power")) {
598 if (wf_get_sensor(sr
) == 0)
599 sensor_slots_power
= sr
;
602 if (sensor_cpu_power
&& sensor_cpu_temp
&&
603 sensor_hd_temp
&& sensor_slots_power
)
604 wf_smu_all_sensors_ok
= 1;
608 static int wf_smu_notify(struct notifier_block
*self
,
609 unsigned long event
, void *data
)
612 case WF_EVENT_NEW_CONTROL
:
613 DBG("wf: new control %s detected\n",
614 ((struct wf_control
*)data
)->name
);
615 wf_smu_new_control(data
);
618 case WF_EVENT_NEW_SENSOR
:
619 DBG("wf: new sensor %s detected\n",
620 ((struct wf_sensor
*)data
)->name
);
621 wf_smu_new_sensor(data
);
624 if (wf_smu_all_controls_ok
&& wf_smu_all_sensors_ok
)
631 static struct notifier_block wf_smu_events
= {
632 .notifier_call
= wf_smu_notify
,
635 static int wf_init_pm(void)
637 printk(KERN_INFO
"windfarm: Initializing for Desktop G5 model\n");
642 static int wf_smu_probe(struct platform_device
*ddev
)
644 wf_register_client(&wf_smu_events
);
649 static int __devexit
wf_smu_remove(struct platform_device
*ddev
)
651 wf_unregister_client(&wf_smu_events
);
653 /* XXX We don't have yet a guarantee that our callback isn't
654 * in progress when returning from wf_unregister_client, so
655 * we add an arbitrary delay. I'll have to fix that in the core
659 /* Release all sensors */
660 /* One more crappy race: I don't think we have any guarantee here
661 * that the attribute callback won't race with the sensor beeing
662 * disposed of, and I'm not 100% certain what best way to deal
663 * with that except by adding locks all over... I'll do that
664 * eventually but heh, who ever rmmod this module anyway ?
666 if (sensor_cpu_power
)
667 wf_put_sensor(sensor_cpu_power
);
669 wf_put_sensor(sensor_cpu_temp
);
671 wf_put_sensor(sensor_hd_temp
);
672 if (sensor_slots_power
)
673 wf_put_sensor(sensor_slots_power
);
675 /* Release all controls */
677 wf_put_control(fan_cpu_main
);
679 wf_put_control(fan_cpu_second
);
681 wf_put_control(fan_cpu_third
);
683 wf_put_control(fan_hd
);
685 wf_put_control(fan_slots
);
687 wf_put_control(cpufreq_clamp
);
689 /* Destroy control loops state structures */
690 kfree(wf_smu_slots_fans
);
691 kfree(wf_smu_drive_fans
);
692 kfree(wf_smu_cpu_fans
);
697 static struct platform_driver wf_smu_driver
= {
698 .probe
= wf_smu_probe
,
699 .remove
= __devexit_p(wf_smu_remove
),
702 .owner
= THIS_MODULE
,
707 static int __init
wf_smu_init(void)
711 if (of_machine_is_compatible("PowerMac9,1"))
716 request_module("windfarm_smu_controls");
717 request_module("windfarm_smu_sensors");
718 request_module("windfarm_lm75_sensor");
719 request_module("windfarm_cpufreq_clamp");
722 platform_driver_register(&wf_smu_driver
);
728 static void __exit
wf_smu_exit(void)
731 platform_driver_unregister(&wf_smu_driver
);
735 module_init(wf_smu_init
);
736 module_exit(wf_smu_exit
);
738 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
739 MODULE_DESCRIPTION("Thermal control logic for PowerMac9,1");
740 MODULE_LICENSE("GPL");
742 MODULE_ALIAS("platform:windfarm");