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 static struct device
*wf_smu_dev
;
68 /* Controls & sensors */
69 static struct wf_sensor
*sensor_cpu_power
;
70 static struct wf_sensor
*sensor_cpu_temp
;
71 static struct wf_sensor
*sensor_hd_temp
;
72 static struct wf_sensor
*sensor_slots_power
;
73 static struct wf_control
*fan_cpu_main
;
74 static struct wf_control
*fan_cpu_second
;
75 static struct wf_control
*fan_cpu_third
;
76 static struct wf_control
*fan_hd
;
77 static struct wf_control
*fan_slots
;
78 static struct wf_control
*cpufreq_clamp
;
80 /* Set to kick the control loop into life */
81 static int wf_smu_all_controls_ok
, wf_smu_all_sensors_ok
, wf_smu_started
;
83 /* Failure handling.. could be nicer */
84 #define FAILURE_FAN 0x01
85 #define FAILURE_SENSOR 0x02
86 #define FAILURE_OVERTEMP 0x04
88 static unsigned int wf_smu_failure_state
;
89 static int wf_smu_readjust
, wf_smu_skipping
;
92 * ****** CPU Fans Control Loop ******
97 #define WF_SMU_CPU_FANS_INTERVAL 1
98 #define WF_SMU_CPU_FANS_MAX_HISTORY 16
100 /* State data used by the cpu fans control loop
102 struct wf_smu_cpu_fans_state
{
105 struct wf_cpu_pid_state pid
;
108 static struct wf_smu_cpu_fans_state
*wf_smu_cpu_fans
;
113 * ****** Drive Fan Control Loop ******
117 struct wf_smu_drive_fans_state
{
120 struct wf_pid_state pid
;
123 static struct wf_smu_drive_fans_state
*wf_smu_drive_fans
;
126 * ****** Slots Fan Control Loop ******
130 struct wf_smu_slots_fans_state
{
133 struct wf_pid_state pid
;
136 static struct wf_smu_slots_fans_state
*wf_smu_slots_fans
;
139 * ***** Implementation *****
144 static void wf_smu_create_cpu_fans(void)
146 struct wf_cpu_pid_param pid_param
;
147 struct smu_sdbp_header
*hdr
;
148 struct smu_sdbp_cpupiddata
*piddata
;
149 struct smu_sdbp_fvt
*fvt
;
150 s32 tmax
, tdelta
, maxpow
, powadj
;
152 /* First, locate the PID params in SMU SBD */
153 hdr
= smu_get_sdb_partition(SMU_SDB_CPUPIDDATA_ID
, NULL
);
155 printk(KERN_WARNING
"windfarm: CPU PID fan config not found "
159 piddata
= (struct smu_sdbp_cpupiddata
*)&hdr
[1];
161 /* Get the FVT params for operating point 0 (the only supported one
162 * for now) in order to get tmax
164 hdr
= smu_get_sdb_partition(SMU_SDB_FVT_ID
, NULL
);
166 fvt
= (struct smu_sdbp_fvt
*)&hdr
[1];
167 tmax
= ((s32
)fvt
->maxtemp
) << 16;
169 tmax
= 0x5e0000; /* 94 degree default */
171 /* Alloc & initialize state */
172 wf_smu_cpu_fans
= kmalloc(sizeof(struct wf_smu_cpu_fans_state
),
174 if (wf_smu_cpu_fans
== NULL
)
176 wf_smu_cpu_fans
->ticks
= 1;
178 /* Fill PID params */
179 pid_param
.interval
= WF_SMU_CPU_FANS_INTERVAL
;
180 pid_param
.history_len
= piddata
->history_len
;
181 if (pid_param
.history_len
> WF_CPU_PID_MAX_HISTORY
) {
182 printk(KERN_WARNING
"windfarm: History size overflow on "
183 "CPU control loop (%d)\n", piddata
->history_len
);
184 pid_param
.history_len
= WF_CPU_PID_MAX_HISTORY
;
186 pid_param
.gd
= piddata
->gd
;
187 pid_param
.gp
= piddata
->gp
;
188 pid_param
.gr
= piddata
->gr
/ pid_param
.history_len
;
190 tdelta
= ((s32
)piddata
->target_temp_delta
) << 16;
191 maxpow
= ((s32
)piddata
->max_power
) << 16;
192 powadj
= ((s32
)piddata
->power_adj
) << 16;
194 pid_param
.tmax
= tmax
;
195 pid_param
.ttarget
= tmax
- tdelta
;
196 pid_param
.pmaxadj
= maxpow
- powadj
;
198 pid_param
.min
= fan_cpu_main
->ops
->get_min(fan_cpu_main
);
199 pid_param
.max
= fan_cpu_main
->ops
->get_max(fan_cpu_main
);
201 wf_cpu_pid_init(&wf_smu_cpu_fans
->pid
, &pid_param
);
203 DBG("wf: CPU Fan control initialized.\n");
204 DBG(" ttarged=%d.%03d, tmax=%d.%03d, min=%d RPM, max=%d RPM\n",
205 FIX32TOPRINT(pid_param
.ttarget
), FIX32TOPRINT(pid_param
.tmax
),
206 pid_param
.min
, pid_param
.max
);
211 printk(KERN_WARNING
"windfarm: CPU fan config not found\n"
212 "for this machine model, max fan speed\n");
215 wf_control_set_max(cpufreq_clamp
);
217 wf_control_set_max(fan_cpu_main
);
220 static void wf_smu_cpu_fans_tick(struct wf_smu_cpu_fans_state
*st
)
222 s32 new_setpoint
, temp
, power
;
225 if (--st
->ticks
!= 0) {
230 st
->ticks
= WF_SMU_CPU_FANS_INTERVAL
;
232 rc
= sensor_cpu_temp
->ops
->get_value(sensor_cpu_temp
, &temp
);
234 printk(KERN_WARNING
"windfarm: CPU temp sensor error %d\n",
236 wf_smu_failure_state
|= FAILURE_SENSOR
;
240 rc
= sensor_cpu_power
->ops
->get_value(sensor_cpu_power
, &power
);
242 printk(KERN_WARNING
"windfarm: CPU power sensor error %d\n",
244 wf_smu_failure_state
|= FAILURE_SENSOR
;
248 DBG("wf_smu: CPU Fans tick ! CPU temp: %d.%03d, power: %d.%03d\n",
249 FIX32TOPRINT(temp
), FIX32TOPRINT(power
));
251 #ifdef HACKED_OVERTEMP
253 wf_smu_failure_state
|= FAILURE_OVERTEMP
;
255 if (temp
> st
->pid
.param
.tmax
)
256 wf_smu_failure_state
|= FAILURE_OVERTEMP
;
258 new_setpoint
= wf_cpu_pid_run(&st
->pid
, power
, temp
);
260 DBG("wf_smu: new_setpoint: %d RPM\n", (int)new_setpoint
);
262 if (st
->cpu_setpoint
== new_setpoint
)
264 st
->cpu_setpoint
= new_setpoint
;
266 if (fan_cpu_main
&& wf_smu_failure_state
== 0) {
267 rc
= fan_cpu_main
->ops
->set_value(fan_cpu_main
,
270 printk(KERN_WARNING
"windfarm: CPU main fan"
272 wf_smu_failure_state
|= FAILURE_FAN
;
275 if (fan_cpu_second
&& wf_smu_failure_state
== 0) {
276 rc
= fan_cpu_second
->ops
->set_value(fan_cpu_second
,
279 printk(KERN_WARNING
"windfarm: CPU second fan"
281 wf_smu_failure_state
|= FAILURE_FAN
;
284 if (fan_cpu_third
&& wf_smu_failure_state
== 0) {
285 rc
= fan_cpu_main
->ops
->set_value(fan_cpu_third
,
288 printk(KERN_WARNING
"windfarm: CPU third fan"
290 wf_smu_failure_state
|= FAILURE_FAN
;
295 static void wf_smu_create_drive_fans(void)
297 struct wf_pid_param param
= {
303 .itarget
= 0x00200000,
306 /* Alloc & initialize state */
307 wf_smu_drive_fans
= kmalloc(sizeof(struct wf_smu_drive_fans_state
),
309 if (wf_smu_drive_fans
== NULL
) {
310 printk(KERN_WARNING
"windfarm: Memory allocation error"
314 wf_smu_drive_fans
->ticks
= 1;
316 /* Fill PID params */
317 param
.additive
= (fan_hd
->type
== WF_CONTROL_RPM_FAN
);
318 param
.min
= fan_hd
->ops
->get_min(fan_hd
);
319 param
.max
= fan_hd
->ops
->get_max(fan_hd
);
320 wf_pid_init(&wf_smu_drive_fans
->pid
, ¶m
);
322 DBG("wf: Drive Fan control initialized.\n");
323 DBG(" itarged=%d.%03d, min=%d RPM, max=%d RPM\n",
324 FIX32TOPRINT(param
.itarget
), param
.min
, param
.max
);
329 wf_control_set_max(fan_hd
);
332 static void wf_smu_drive_fans_tick(struct wf_smu_drive_fans_state
*st
)
334 s32 new_setpoint
, temp
;
337 if (--st
->ticks
!= 0) {
342 st
->ticks
= st
->pid
.param
.interval
;
344 rc
= sensor_hd_temp
->ops
->get_value(sensor_hd_temp
, &temp
);
346 printk(KERN_WARNING
"windfarm: HD temp sensor error %d\n",
348 wf_smu_failure_state
|= FAILURE_SENSOR
;
352 DBG("wf_smu: Drive Fans tick ! HD temp: %d.%03d\n",
355 if (temp
> (st
->pid
.param
.itarget
+ 0x50000))
356 wf_smu_failure_state
|= FAILURE_OVERTEMP
;
358 new_setpoint
= wf_pid_run(&st
->pid
, temp
);
360 DBG("wf_smu: new_setpoint: %d\n", (int)new_setpoint
);
362 if (st
->setpoint
== new_setpoint
)
364 st
->setpoint
= new_setpoint
;
366 if (fan_hd
&& wf_smu_failure_state
== 0) {
367 rc
= fan_hd
->ops
->set_value(fan_hd
, st
->setpoint
);
369 printk(KERN_WARNING
"windfarm: HD fan error %d\n",
371 wf_smu_failure_state
|= FAILURE_FAN
;
376 static void wf_smu_create_slots_fans(void)
378 struct wf_pid_param param
= {
384 .itarget
= 0x00000000
387 /* Alloc & initialize state */
388 wf_smu_slots_fans
= kmalloc(sizeof(struct wf_smu_slots_fans_state
),
390 if (wf_smu_slots_fans
== NULL
) {
391 printk(KERN_WARNING
"windfarm: Memory allocation error"
395 wf_smu_slots_fans
->ticks
= 1;
397 /* Fill PID params */
398 param
.additive
= (fan_slots
->type
== WF_CONTROL_RPM_FAN
);
399 param
.min
= fan_slots
->ops
->get_min(fan_slots
);
400 param
.max
= fan_slots
->ops
->get_max(fan_slots
);
401 wf_pid_init(&wf_smu_slots_fans
->pid
, ¶m
);
403 DBG("wf: Slots Fan control initialized.\n");
404 DBG(" itarged=%d.%03d, min=%d RPM, max=%d RPM\n",
405 FIX32TOPRINT(param
.itarget
), param
.min
, param
.max
);
410 wf_control_set_max(fan_slots
);
413 static void wf_smu_slots_fans_tick(struct wf_smu_slots_fans_state
*st
)
415 s32 new_setpoint
, power
;
418 if (--st
->ticks
!= 0) {
423 st
->ticks
= st
->pid
.param
.interval
;
425 rc
= sensor_slots_power
->ops
->get_value(sensor_slots_power
, &power
);
427 printk(KERN_WARNING
"windfarm: Slots power sensor error %d\n",
429 wf_smu_failure_state
|= FAILURE_SENSOR
;
433 DBG("wf_smu: Slots Fans tick ! Slots power: %d.%03d\n",
434 FIX32TOPRINT(power
));
436 #if 0 /* Check what makes a good overtemp condition */
437 if (power
> (st
->pid
.param
.itarget
+ 0x50000))
438 wf_smu_failure_state
|= FAILURE_OVERTEMP
;
441 new_setpoint
= wf_pid_run(&st
->pid
, power
);
443 DBG("wf_smu: new_setpoint: %d\n", (int)new_setpoint
);
445 if (st
->setpoint
== new_setpoint
)
447 st
->setpoint
= new_setpoint
;
449 if (fan_slots
&& wf_smu_failure_state
== 0) {
450 rc
= fan_slots
->ops
->set_value(fan_slots
, st
->setpoint
);
452 printk(KERN_WARNING
"windfarm: Slots fan error %d\n",
454 wf_smu_failure_state
|= FAILURE_FAN
;
461 * ****** Setup / Init / Misc ... ******
465 static void wf_smu_tick(void)
467 unsigned int last_failure
= wf_smu_failure_state
;
468 unsigned int new_failure
;
470 if (!wf_smu_started
) {
471 DBG("wf: creating control loops !\n");
472 wf_smu_create_drive_fans();
473 wf_smu_create_slots_fans();
474 wf_smu_create_cpu_fans();
479 if (wf_smu_skipping
&& --wf_smu_skipping
)
482 wf_smu_failure_state
= 0;
483 if (wf_smu_drive_fans
)
484 wf_smu_drive_fans_tick(wf_smu_drive_fans
);
485 if (wf_smu_slots_fans
)
486 wf_smu_slots_fans_tick(wf_smu_slots_fans
);
488 wf_smu_cpu_fans_tick(wf_smu_cpu_fans
);
491 new_failure
= wf_smu_failure_state
& ~last_failure
;
493 /* If entering failure mode, clamp cpufreq and ramp all
494 * fans to full speed.
496 if (wf_smu_failure_state
&& !last_failure
) {
498 wf_control_set_max(cpufreq_clamp
);
500 wf_control_set_max(fan_cpu_main
);
502 wf_control_set_max(fan_cpu_second
);
504 wf_control_set_max(fan_cpu_third
);
506 wf_control_set_max(fan_hd
);
508 wf_control_set_max(fan_slots
);
511 /* If leaving failure mode, unclamp cpufreq and readjust
512 * all fans on next iteration
514 if (!wf_smu_failure_state
&& last_failure
) {
516 wf_control_set_min(cpufreq_clamp
);
520 /* Overtemp condition detected, notify and start skipping a couple
521 * ticks to let the temperature go down
523 if (new_failure
& FAILURE_OVERTEMP
) {
528 /* We only clear the overtemp condition if overtemp is cleared
529 * _and_ no other failure is present. Since a sensor error will
530 * clear the overtemp condition (can't measure temperature) at
531 * the control loop levels, but we don't want to keep it clear
534 if (new_failure
== 0 && last_failure
& FAILURE_OVERTEMP
)
539 static void wf_smu_new_control(struct wf_control
*ct
)
541 if (wf_smu_all_controls_ok
)
544 if (fan_cpu_main
== NULL
&& !strcmp(ct
->name
, "cpu-rear-fan-0")) {
545 if (wf_get_control(ct
) == 0)
549 if (fan_cpu_second
== NULL
&& !strcmp(ct
->name
, "cpu-rear-fan-1")) {
550 if (wf_get_control(ct
) == 0)
554 if (fan_cpu_third
== NULL
&& !strcmp(ct
->name
, "cpu-front-fan-0")) {
555 if (wf_get_control(ct
) == 0)
559 if (cpufreq_clamp
== NULL
&& !strcmp(ct
->name
, "cpufreq-clamp")) {
560 if (wf_get_control(ct
) == 0)
564 if (fan_hd
== NULL
&& !strcmp(ct
->name
, "drive-bay-fan")) {
565 if (wf_get_control(ct
) == 0)
569 if (fan_slots
== NULL
&& !strcmp(ct
->name
, "slots-fan")) {
570 if (wf_get_control(ct
) == 0)
574 if (fan_cpu_main
&& (fan_cpu_second
|| fan_cpu_third
) && fan_hd
&&
575 fan_slots
&& cpufreq_clamp
)
576 wf_smu_all_controls_ok
= 1;
579 static void wf_smu_new_sensor(struct wf_sensor
*sr
)
581 if (wf_smu_all_sensors_ok
)
584 if (sensor_cpu_power
== NULL
&& !strcmp(sr
->name
, "cpu-power")) {
585 if (wf_get_sensor(sr
) == 0)
586 sensor_cpu_power
= sr
;
589 if (sensor_cpu_temp
== NULL
&& !strcmp(sr
->name
, "cpu-temp")) {
590 if (wf_get_sensor(sr
) == 0)
591 sensor_cpu_temp
= sr
;
594 if (sensor_hd_temp
== NULL
&& !strcmp(sr
->name
, "hd-temp")) {
595 if (wf_get_sensor(sr
) == 0)
599 if (sensor_slots_power
== NULL
&& !strcmp(sr
->name
, "slots-power")) {
600 if (wf_get_sensor(sr
) == 0)
601 sensor_slots_power
= sr
;
604 if (sensor_cpu_power
&& sensor_cpu_temp
&&
605 sensor_hd_temp
&& sensor_slots_power
)
606 wf_smu_all_sensors_ok
= 1;
610 static int wf_smu_notify(struct notifier_block
*self
,
611 unsigned long event
, void *data
)
614 case WF_EVENT_NEW_CONTROL
:
615 DBG("wf: new control %s detected\n",
616 ((struct wf_control
*)data
)->name
);
617 wf_smu_new_control(data
);
620 case WF_EVENT_NEW_SENSOR
:
621 DBG("wf: new sensor %s detected\n",
622 ((struct wf_sensor
*)data
)->name
);
623 wf_smu_new_sensor(data
);
626 if (wf_smu_all_controls_ok
&& wf_smu_all_sensors_ok
)
633 static struct notifier_block wf_smu_events
= {
634 .notifier_call
= wf_smu_notify
,
637 static int wf_init_pm(void)
639 printk(KERN_INFO
"windfarm: Initializing for Desktop G5 model\n");
644 static int wf_smu_probe(struct device
*ddev
)
648 wf_register_client(&wf_smu_events
);
653 static int wf_smu_remove(struct device
*ddev
)
655 wf_unregister_client(&wf_smu_events
);
657 /* XXX We don't have yet a guarantee that our callback isn't
658 * in progress when returning from wf_unregister_client, so
659 * we add an arbitrary delay. I'll have to fix that in the core
663 /* Release all sensors */
664 /* One more crappy race: I don't think we have any guarantee here
665 * that the attribute callback won't race with the sensor beeing
666 * disposed of, and I'm not 100% certain what best way to deal
667 * with that except by adding locks all over... I'll do that
668 * eventually but heh, who ever rmmod this module anyway ?
670 if (sensor_cpu_power
)
671 wf_put_sensor(sensor_cpu_power
);
673 wf_put_sensor(sensor_cpu_temp
);
675 wf_put_sensor(sensor_hd_temp
);
676 if (sensor_slots_power
)
677 wf_put_sensor(sensor_slots_power
);
679 /* Release all controls */
681 wf_put_control(fan_cpu_main
);
683 wf_put_control(fan_cpu_second
);
685 wf_put_control(fan_cpu_third
);
687 wf_put_control(fan_hd
);
689 wf_put_control(fan_slots
);
691 wf_put_control(cpufreq_clamp
);
693 /* Destroy control loops state structures */
694 if (wf_smu_slots_fans
)
695 kfree(wf_smu_cpu_fans
);
696 if (wf_smu_drive_fans
)
697 kfree(wf_smu_cpu_fans
);
699 kfree(wf_smu_cpu_fans
);
706 static struct device_driver wf_smu_driver
= {
708 .bus
= &platform_bus_type
,
709 .probe
= wf_smu_probe
,
710 .remove
= wf_smu_remove
,
714 static int __init
wf_smu_init(void)
718 if (machine_is_compatible("PowerMac9,1"))
723 request_module("windfarm_smu_controls");
724 request_module("windfarm_smu_sensors");
725 request_module("windfarm_lm75_sensor");
728 driver_register(&wf_smu_driver
);
734 static void __exit
wf_smu_exit(void)
737 driver_unregister(&wf_smu_driver
);
741 module_init(wf_smu_init
);
742 module_exit(wf_smu_exit
);
744 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
745 MODULE_DESCRIPTION("Thermal control logic for PowerMac9,1");
746 MODULE_LICENSE("GPL");