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 const 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");