2 * Windfarm PowerMac thermal control. iMac G5 iSight
4 * (c) Copyright 2007 Étienne Bersac <bersace@gmail.com>
6 * Bits & pieces from windfarm_pm81.c by (c) Copyright 2005 Benjamin
7 * Herrenschmidt, IBM Corp. <benh@kernel.crashing.org>
9 * Released under the term of the GNU GPL v2.
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
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.
31 * controls have a target correction calculated as :
33 * new_min = ((((average_power * slope) >> 16) + offset) >> 16) + min_value
34 * new_value = max(new_value, max(new_min, 0))
36 * OD Fan control correction.
46 * HD Fan control correction.
56 * CPU Fan control correction.
67 * Target rubber-banding :
69 * Some controls have a target correction which depends on another
70 * control value. The correction is computed in the following way :
72 * new_min = ref_value * slope + offset
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 :
77 * new_target = max (new_target, new_min >> 16)
82 * ref : optical-drive-fan
87 * control : optical-drive-fan
88 * ref : hard-drive-fan
93 * In order to have the moste efficient correction with those
94 * dependencies, we must trigger HD loop before OD loop before CPU
98 * The various control loops found in Darwin config file are:
100 * HD Fan control loop.
103 * control : hard-drive-fan
104 * sensor : hard-drive-temp
105 * PID params : G_d = 0x00000000
108 * History = 2 entries
109 * Input target = 0x370000
113 * control : hard-drive-fan
114 * sensor : hard-drive-temp
115 * PID params : G_d = 0x00000000
118 * History = 2 entries
119 * Input target = 0x370000
122 * OD Fan control loop.
125 * control : optical-drive-fan
126 * sensor : optical-drive-temp
127 * PID params : G_d = 0x00000000
130 * History = 2 entries
131 * Input target = 0x320000
135 * control : optical-drive-fan
136 * sensor : optical-drive-temp
137 * PID params : G_d = 0x00000000
140 * History = 2 entries
141 * Input target = 0x320000
144 * GPU Fan control loop.
147 * control : hard-drive-fan
149 * PID params : G_d = 0x00000000
152 * History = 2 entries
153 * Input target = 0x5A0000
159 * PID params : G_d = 0x00000000
162 * History = 2 entries
163 * Input target = 0x500000
166 * KODIAK (aka northbridge) Fan control loop.
169 * control : optical-drive-fan
170 * sensor : north-bridge-temp
171 * PID params : G_d = 0x00000000
174 * History = 2 entries
175 * Input target = 0x550000
179 * control : hard-drive-fan
180 * sensor : north-bridge-temp
181 * PID params : G_d = 0x00000000
184 * History = 2 entries
185 * Input target = 0x550000
188 * CPU Fan control loop.
191 * sensors : cpu-temp, cpu-power
192 * PID params : from SDB partition
195 * CPU Slew control loop.
197 * control : cpufreq-clamp
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>
218 #include <asm/system.h>
219 #include <asm/sections.h>
222 #include "windfarm.h"
223 #include "windfarm_pid.h"
225 #define VERSION "0.3"
227 static int pm121_mach_model; /* machine model id */
229 /* Controls & sensors */
230 static struct wf_sensor *sensor_cpu_power;
231 static struct wf_sensor *sensor_cpu_temp;
232 static struct wf_sensor *sensor_cpu_voltage;
233 static struct wf_sensor *sensor_cpu_current;
234 static struct wf_sensor *sensor_gpu_temp;
235 static struct wf_sensor *sensor_north_bridge_temp;
236 static struct wf_sensor *sensor_hard_drive_temp;
237 static struct wf_sensor *sensor_optical_drive_temp;
238 static struct wf_sensor *sensor_incoming_air_temp; /* unused ! */
247 static struct wf_control *controls[N_CONTROLS] = {};
249 /* Set to kick the control loop into life */
250 static int pm121_all_controls_ok, pm121_all_sensors_ok, pm121_started;
253 FAILURE_FAN = 1 << 0,
254 FAILURE_SENSOR = 1 << 1,
255 FAILURE_OVERTEMP = 1 << 2
258 /* All sys loops. Note the HD before the OD loop in order to have it
261 LOOP_GPU, /* control = hd or cpu, but luckily,
263 LOOP_HD, /* control = hd */
264 LOOP_KODIAK, /* control = hd or od */
265 LOOP_OD, /* control = od */
269 static const char *loop_names[N_LOOPS] = {
276 #define PM121_NUM_CONFIGS 2
278 static unsigned int pm121_failure_state;
279 static int pm121_readjust, pm121_skipping;
280 static s32 average_power;
282 struct pm121_correction {
287 static struct pm121_correction corrections[N_CONTROLS][PM121_NUM_CONFIGS] = {
291 { .offset = -19563152,
295 { .offset = -15650652,
302 { .offset = -15650652,
306 { .offset = -19563152,
313 { .offset = -25431900,
317 { .offset = -15650652,
321 /* CPUFREQ has no correction (and is not implemented at all) */
324 struct pm121_connection {
325 unsigned int control_id;
327 struct pm121_correction correction;
330 static struct pm121_connection pm121_connections[] = {
332 { .control_id = FAN_CPU,
334 { .offset = -32768000,
339 { .control_id = FAN_OD,
341 { .offset = -32768000,
347 /* pointer to the current model connection */
348 static struct pm121_connection *pm121_connection;
351 * ****** System Fans Control Loop ******
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.
360 struct pm121_sys_param {
361 /* purely informative since we use mach_model-2 as index */
363 struct wf_sensor **sensor; /* use sensor_id instead ? */
365 unsigned int control_id;
368 static struct pm121_sys_param
369 pm121_sys_all_params[N_LOOPS][PM121_NUM_CONFIGS] = {
370 /* GPU Fan control loop */
373 .sensor = &sensor_gpu_temp,
376 .control_id = FAN_HD,
379 .sensor = &sensor_gpu_temp,
382 .control_id = FAN_CPU,
385 /* HD Fan control loop */
388 .sensor = &sensor_hard_drive_temp,
391 .control_id = FAN_HD,
394 .sensor = &sensor_hard_drive_temp,
397 .control_id = FAN_HD,
400 /* KODIAK Fan control loop */
403 .sensor = &sensor_north_bridge_temp,
406 .control_id = FAN_OD,
409 .sensor = &sensor_north_bridge_temp,
412 .control_id = FAN_HD,
415 /* OD Fan control loop */
418 .sensor = &sensor_optical_drive_temp,
421 .control_id = FAN_OD,
424 .sensor = &sensor_optical_drive_temp,
427 .control_id = FAN_OD,
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
438 /* State data used by the system fans control loop
440 struct pm121_sys_state {
443 struct wf_pid_state pid;
446 struct pm121_sys_state *pm121_sys_state[N_LOOPS] = {};
449 * ****** CPU Fans Control Loop ******
453 #define PM121_CPU_INTERVAL 1
455 /* State data used by the cpu fans control loop
457 struct pm121_cpu_state {
460 struct wf_cpu_pid_state pid;
463 static struct pm121_cpu_state *pm121_cpu_state;
468 * ***** Implementation *****
472 /* correction the value using the output-low-bound correction algo */
473 static s32 pm121_correct(s32 new_setpoint,
474 unsigned int control_id,
478 struct pm121_correction *correction;
479 correction = &corrections[control_id][pm121_mach_model - 2];
481 new_min = (average_power * correction->slope) >> 16;
482 new_min += correction->offset;
483 new_min = (new_min >> 16) + min;
485 return max(new_setpoint, max(new_min, 0));
488 static s32 pm121_connect(unsigned int control_id, s32 setpoint)
490 s32 new_min, value, new_setpoint;
492 if (pm121_connection->control_id == control_id) {
493 controls[control_id]->ops->get_value(controls[control_id],
495 new_min = value * pm121_connection->correction.slope;
496 new_min += pm121_connection->correction.offset;
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);
507 new_setpoint = setpoint;
511 new_setpoint = setpoint;
517 static void pm121_create_sys_fans(int loop_id)
519 struct pm121_sys_param *param = NULL;
520 struct wf_pid_param pid_param;
521 struct wf_control *control = NULL;
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]);
532 /* No params found, put fans to max */
534 printk(KERN_WARNING "pm121: %s fan config not found "
535 " for this machine model\n",
536 loop_names[loop_id]);
540 control = controls[param->control_id];
542 /* Alloc & initialize state */
543 pm121_sys_state[loop_id] = kmalloc(sizeof(struct pm121_sys_state),
545 if (pm121_sys_state[loop_id] == NULL) {
546 printk(KERN_WARNING "pm121: Memory allocation error\n");
549 pm121_sys_state[loop_id]->ticks = 1;
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);
561 wf_pid_init(&pm121_sys_state[loop_id]->pid, &pid_param);
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);
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);
577 wf_control_set_max(control);
580 static void pm121_sys_fans_tick(int loop_id)
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;
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];
594 if (--st->ticks != 0) {
599 st->ticks = PM121_SYS_INTERVAL;
601 rc = sensor->ops->get_value(sensor, &temp);
603 printk(KERN_WARNING "windfarm: %s sensor error %d\n",
605 pm121_failure_state |= FAILURE_SENSOR;
609 pr_debug("pm121: %s Fan tick ! %s: %d.%03d\n",
610 loop_names[loop_id], sensor->name,
613 new_setpoint = wf_pid_run(&st->pid, temp);
616 new_setpoint = pm121_correct(new_setpoint,
619 /* linked corretion */
620 new_setpoint = pm121_connect(param->control_id, new_setpoint);
622 if (new_setpoint == st->setpoint)
624 st->setpoint = new_setpoint;
625 pr_debug("pm121: %s corrected setpoint: %d RPM\n",
626 control->name, (int)new_setpoint);
628 if (control && pm121_failure_state == 0) {
629 rc = control->ops->set_value(control, st->setpoint);
631 printk(KERN_WARNING "windfarm: %s fan error %d\n",
633 pm121_failure_state |= FAILURE_FAN;
640 static void pm121_create_cpu_fans(void)
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;
649 fan_cpu = controls[FAN_CPU];
651 /* First, locate the PID params in SMU SBD */
652 hdr = smu_get_sdb_partition(SMU_SDB_CPUPIDDATA_ID, NULL);
654 printk(KERN_WARNING "pm121: CPU PID fan config not found.\n");
657 piddata = (struct smu_sdbp_cpupiddata *)&hdr[1];
659 /* Get the FVT params for operating point 0 (the only supported one
660 * for now) in order to get tmax
662 hdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL);
664 fvt = (struct smu_sdbp_fvt *)&hdr[1];
665 tmax = ((s32)fvt->maxtemp) << 16;
667 tmax = 0x5e0000; /* 94 degree default */
669 /* Alloc & initialize state */
670 pm121_cpu_state = kmalloc(sizeof(struct pm121_cpu_state),
672 if (pm121_cpu_state == NULL)
674 pm121_cpu_state->ticks = 1;
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;
684 pid_param.gd = piddata->gd;
685 pid_param.gp = piddata->gp;
686 pid_param.gr = piddata->gr / pid_param.history_len;
688 tdelta = ((s32)piddata->target_temp_delta) << 16;
689 maxpow = ((s32)piddata->max_power) << 16;
690 powadj = ((s32)piddata->power_adj) << 16;
692 pid_param.tmax = tmax;
693 pid_param.ttarget = tmax - tdelta;
694 pid_param.pmaxadj = maxpow - powadj;
696 pid_param.min = fan_cpu->ops->get_min(fan_cpu);
697 pid_param.max = fan_cpu->ops->get_max(fan_cpu);
699 wf_cpu_pid_init(&pm121_cpu_state->pid, &pid_param);
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);
709 printk(KERN_WARNING "pm121: CPU fan config not found, max fan speed\n");
711 if (controls[CPUFREQ])
712 wf_control_set_max(controls[CPUFREQ]);
714 wf_control_set_max(fan_cpu);
718 static void pm121_cpu_fans_tick(struct pm121_cpu_state *st)
720 s32 new_setpoint, temp, power;
721 struct wf_control *fan_cpu = NULL;
724 if (--st->ticks != 0) {
729 st->ticks = PM121_CPU_INTERVAL;
731 fan_cpu = controls[FAN_CPU];
733 rc = sensor_cpu_temp->ops->get_value(sensor_cpu_temp, &temp);
735 printk(KERN_WARNING "pm121: CPU temp sensor error %d\n",
737 pm121_failure_state |= FAILURE_SENSOR;
741 rc = sensor_cpu_power->ops->get_value(sensor_cpu_power, &power);
743 printk(KERN_WARNING "pm121: CPU power sensor error %d\n",
745 pm121_failure_state |= FAILURE_SENSOR;
749 pr_debug("pm121: CPU Fans tick ! CPU temp: %d.%03d°C, power: %d.%03d\n",
750 FIX32TOPRINT(temp), FIX32TOPRINT(power));
752 if (temp > st->pid.param.tmax)
753 pm121_failure_state |= FAILURE_OVERTEMP;
755 new_setpoint = wf_cpu_pid_run(&st->pid, power, temp);
758 new_setpoint = pm121_correct(new_setpoint,
762 /* connected correction */
763 new_setpoint = pm121_connect(FAN_CPU, new_setpoint);
765 if (st->setpoint == new_setpoint)
767 st->setpoint = new_setpoint;
768 pr_debug("pm121: CPU corrected setpoint: %d RPM\n", (int)new_setpoint);
771 if (fan_cpu && pm121_failure_state == 0) {
772 rc = fan_cpu->ops->set_value(fan_cpu, st->setpoint);
774 printk(KERN_WARNING "pm121: %s fan error %d\n",
776 pm121_failure_state |= FAILURE_FAN;
782 * ****** Common ******
786 static void pm121_tick(void)
788 unsigned int last_failure = pm121_failure_state;
789 unsigned int new_failure;
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);
798 pm121_create_cpu_fans();
803 if (pm121_skipping && --pm121_skipping)
806 /* compute average power */
808 for (i = 0; i < pm121_cpu_state->pid.param.history_len; i++)
809 total_power += pm121_cpu_state->pid.powers[i];
811 average_power = total_power / pm121_cpu_state->pid.param.history_len;
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);
821 pm121_cpu_fans_tick(pm121_cpu_state);
824 new_failure = pm121_failure_state & ~last_failure;
826 /* If entering failure mode, clamp cpufreq and ramp all
827 * fans to full speed.
829 if (pm121_failure_state && !last_failure) {
830 for (i = 0; i < N_CONTROLS; i++) {
832 wf_control_set_max(controls[i]);
836 /* If leaving failure mode, unclamp cpufreq and readjust
837 * all fans on next iteration
839 if (!pm121_failure_state && last_failure) {
840 if (controls[CPUFREQ])
841 wf_control_set_min(controls[CPUFREQ]);
845 /* Overtemp condition detected, notify and start skipping a couple
846 * ticks to let the temperature go down
848 if (new_failure & FAILURE_OVERTEMP) {
853 /* We only clear the overtemp condition if overtemp is cleared
854 * _and_ no other failure is present. Since a sensor error will
855 * clear the overtemp condition (can't measure temperature) at
856 * the control loop levels, but we don't want to keep it clear
859 if (new_failure == 0 && last_failure & FAILURE_OVERTEMP)
864 static struct wf_control* pm121_register_control(struct wf_control *ct,
868 if (controls[id] == NULL && !strcmp(ct->name, match)) {
869 if (wf_get_control(ct) == 0)
875 static void pm121_new_control(struct wf_control *ct)
879 if (pm121_all_controls_ok)
882 all = pm121_register_control(ct, "optical-drive-fan", FAN_OD) && all;
883 all = pm121_register_control(ct, "hard-drive-fan", FAN_HD) && all;
884 all = pm121_register_control(ct, "cpu-fan", FAN_CPU) && all;
885 all = pm121_register_control(ct, "cpufreq-clamp", CPUFREQ) && all;
888 pm121_all_controls_ok = 1;
894 static struct wf_sensor* pm121_register_sensor(struct wf_sensor *sensor,
896 struct wf_sensor **var)
898 if (*var == NULL && !strcmp(sensor->name, match)) {
899 if (wf_get_sensor(sensor) == 0)
905 static void pm121_new_sensor(struct wf_sensor *sr)
909 if (pm121_all_sensors_ok)
912 all = pm121_register_sensor(sr, "cpu-temp",
913 &sensor_cpu_temp) && all;
914 all = pm121_register_sensor(sr, "cpu-current",
915 &sensor_cpu_current) && all;
916 all = pm121_register_sensor(sr, "cpu-voltage",
917 &sensor_cpu_voltage) && all;
918 all = pm121_register_sensor(sr, "cpu-power",
919 &sensor_cpu_power) && all;
920 all = pm121_register_sensor(sr, "hard-drive-temp",
921 &sensor_hard_drive_temp) && all;
922 all = pm121_register_sensor(sr, "optical-drive-temp",
923 &sensor_optical_drive_temp) && all;
924 all = pm121_register_sensor(sr, "incoming-air-temp",
925 &sensor_incoming_air_temp) && all;
926 all = pm121_register_sensor(sr, "north-bridge-temp",
927 &sensor_north_bridge_temp) && all;
928 all = pm121_register_sensor(sr, "gpu-temp",
929 &sensor_gpu_temp) && all;
932 pm121_all_sensors_ok = 1;
937 static int pm121_notify(struct notifier_block *self,
938 unsigned long event, void *data)
941 case WF_EVENT_NEW_CONTROL:
942 pr_debug("pm121: new control %s detected\n",
943 ((struct wf_control *)data)->name);
944 pm121_new_control(data);
946 case WF_EVENT_NEW_SENSOR:
947 pr_debug("pm121: new sensor %s detected\n",
948 ((struct wf_sensor *)data)->name);
949 pm121_new_sensor(data);
952 if (pm121_all_controls_ok && pm121_all_sensors_ok)
960 static struct notifier_block pm121_events = {
961 .notifier_call = pm121_notify,
964 static int pm121_init_pm(void)
966 const struct smu_sdbp_header *hdr;
968 hdr = smu_get_sdb_partition(SMU_SDB_SENSORTREE_ID, NULL);
970 struct smu_sdbp_sensortree *st =
971 (struct smu_sdbp_sensortree *)&hdr[1];
972 pm121_mach_model = st->model_id;
975 pm121_connection = &pm121_connections[pm121_mach_model - 2];
977 printk(KERN_INFO "pm121: Initializing for iMac G5 iSight model ID %d\n",
984 static int pm121_probe(struct platform_device *ddev)
986 wf_register_client(&pm121_events);
991 static int __devexit pm121_remove(struct platform_device *ddev)
993 wf_unregister_client(&pm121_events);
997 static struct platform_driver pm121_driver = {
998 .probe = pm121_probe,
999 .remove = __devexit_p(pm121_remove),
1002 .bus = &platform_bus_type,
1007 static int __init pm121_init(void)
1011 if (machine_is_compatible("PowerMac12,1"))
1012 rc = pm121_init_pm();
1015 request_module("windfarm_smu_controls");
1016 request_module("windfarm_smu_sensors");
1017 request_module("windfarm_smu_sat");
1018 request_module("windfarm_lm75_sensor");
1019 request_module("windfarm_max6690_sensor");
1020 request_module("windfarm_cpufreq_clamp");
1021 platform_driver_register(&pm121_driver);
1027 static void __exit pm121_exit(void)
1030 platform_driver_unregister(&pm121_driver);
1034 module_init(pm121_init);
1035 module_exit(pm121_exit);
1037 MODULE_AUTHOR("Étienne Bersac <bersace@gmail.com>");
1038 MODULE_DESCRIPTION("Thermal control logic for iMac G5 (iSight)");
1039 MODULE_LICENSE("GPL");