1 // SPDX-License-Identifier: GPL-2.0-only
3  * Windfarm PowerMac thermal control. iMac G5
8  * The algorithm used is the PID control algorithm, used the same
11  * that none of the code has been re-used, it's a complete re-implementation
13  * The various control loops found in Darwin config file are:
18  * System Fans control loop. Different based on models. In addition to the
19  * usual PID algorithm, the control loop gets 2 additional pairs of linear
24  *  - the linked control (second control) gets the target value as-is
26  *  - the main control (first control) gets the target value scaled with
28  *  - the value of the target of the CPU Fan control loop is retrieved,
30  *    the scaled target is applied to the main control.
33  *   controls       : system-fan, drive-bay-fan
34  *   sensors        : hd-temp
41  *   linear-factors : offset = 0xff38 scale  = 0x0ccd
45  *   controls       : system-fan, drive-bay-fan
46  *   sensors        : hd-temp
53  *   linear-factors : offset = 0xff38 scale  = 0x0ccd
57  *   controls       : system-fan
58  *   sensors        : hd-temp
65  *   linear-factors : offset = 0x0000 scale  = 0x1000
68  * CPU Fan control loop. The loop is identical for all models. it
70  * systems fan control loop target result (the one before it gets scaled
71  * by the System Fans control loop itself). Then, the max value of the
72  * calculated target value and system fan value is sent to the fans
74  *   controls       : cpu-fan
75  *   sensors        : cpu-temp cpu-power
77  *   linear-factors : offset = 0xfb50 scale  = 0x1000
79  * CPU Slew control loop. Not implemented. The cpufreq driver in linux is
84  * WARNING ! The CPU control loop requires the CPU tmax for the current
89  * from the SDB partition. If we ever end up with actually slewing the system
141 /* Set to kick the control loop into life */
155  * ****** System Fans Control Loop ******
159 /* Parameters for the System Fans control loop. Parameters
177 /* State data used by the system fans control loop
191  * Configs for SMU System Fan control loop
236  * ****** CPU Fans Control Loop ******
246 /* State data used by the cpu fans control loop
280 		printk(KERN_WARNING "windfarm: System fan config not found "  in wf_smu_create_sys_fans()
293 	wf_smu_sys_fans->ticks = 1;  in wf_smu_create_sys_fans()
294 	wf_smu_sys_fans->scale0 = param->scale0;  in wf_smu_create_sys_fans()
295 	wf_smu_sys_fans->offset0 = param->offset0;  in wf_smu_create_sys_fans()
296 	wf_smu_sys_fans->scale1 = param->scale1;  in wf_smu_create_sys_fans()
297 	wf_smu_sys_fans->offset1 = param->offset1;  in wf_smu_create_sys_fans()
300 	pid_param.gd = param->gd;  in wf_smu_create_sys_fans()
301 	pid_param.gp = param->gp;  in wf_smu_create_sys_fans()
302 	pid_param.gr = param->gr;  in wf_smu_create_sys_fans()
305 	pid_param.itarget = param->itarget;  in wf_smu_create_sys_fans()
314 	wf_pid_init(&wf_smu_sys_fans->pid, &pid_param);  in wf_smu_create_sys_fans()
316 	DBG("wf: System Fan control initialized.\n");  in wf_smu_create_sys_fans()
334 	if (--st->ticks != 0) {  in wf_smu_sys_fans_tick()
339 	st->ticks = WF_SMU_SYS_FANS_INTERVAL;  in wf_smu_sys_fans_tick()
349 	DBG("wf_smu: System Fans tick ! HD temp: %d.%03d\n",  in wf_smu_sys_fans_tick()
352 	if (temp > (st->pid.param.itarget + 0x50000))  in wf_smu_sys_fans_tick()
355 	new_setpoint = wf_pid_run(&st->pid, temp);  in wf_smu_sys_fans_tick()
359 	scaled = ((((s64)new_setpoint) * (s64)st->scale0) >> 12) + st->offset0;  in wf_smu_sys_fans_tick()
363 	cputarget = wf_smu_cpu_fans ? wf_smu_cpu_fans->pid.target : 0;  in wf_smu_sys_fans_tick()
364 	cputarget = ((((s64)cputarget) * (s64)st->scale1) >> 12) + st->offset1;  in wf_smu_sys_fans_tick()
366 	scaled = max(scaled, st->pid.param.min);  in wf_smu_sys_fans_tick()
367 	scaled = min(scaled, st->pid.param.max);  in wf_smu_sys_fans_tick()
371 	if (st->sys_setpoint == scaled && new_setpoint == st->hd_setpoint)  in wf_smu_sys_fans_tick()
373 	st->sys_setpoint = scaled;  in wf_smu_sys_fans_tick()
374 	st->hd_setpoint = new_setpoint;  in wf_smu_sys_fans_tick()
377 		rc = wf_control_set(fan_system, st->sys_setpoint);  in wf_smu_sys_fans_tick()
385 		rc = wf_control_set(fan_hd, st->hd_setpoint);  in wf_smu_sys_fans_tick()
417 		tmax = ((s32)fvt->maxtemp) << 16;  in wf_smu_create_cpu_fans()
426        	wf_smu_cpu_fans->ticks = 1;  in wf_smu_create_cpu_fans()
428 	wf_smu_cpu_fans->scale = WF_SMU_CPU_FANS_SIBLING_SCALE;  in wf_smu_create_cpu_fans()
429 	wf_smu_cpu_fans->offset = WF_SMU_CPU_FANS_SIBLING_OFFSET;  in wf_smu_create_cpu_fans()
433 	pid_param.history_len = piddata->history_len;  in wf_smu_create_cpu_fans()
436 		       "CPU control loop (%d)\n", piddata->history_len);  in wf_smu_create_cpu_fans()
439 	pid_param.gd = piddata->gd;  in wf_smu_create_cpu_fans()
440 	pid_param.gp = piddata->gp;  in wf_smu_create_cpu_fans()
441 	pid_param.gr = piddata->gr / pid_param.history_len;  in wf_smu_create_cpu_fans()
443 	tdelta = ((s32)piddata->target_temp_delta) << 16;  in wf_smu_create_cpu_fans()
444 	maxpow = ((s32)piddata->max_power) << 16;  in wf_smu_create_cpu_fans()
445 	powadj = ((s32)piddata->power_adj) << 16;  in wf_smu_create_cpu_fans()
448 	pid_param.ttarget = tmax - tdelta;  in wf_smu_create_cpu_fans()
449 	pid_param.pmaxadj = maxpow - powadj;  in wf_smu_create_cpu_fans()
454 	wf_cpu_pid_init(&wf_smu_cpu_fans->pid, &pid_param);  in wf_smu_create_cpu_fans()
456 	DBG("wf: CPU Fan control initialized.\n");  in wf_smu_create_cpu_fans()
478 	if (--st->ticks != 0) {  in wf_smu_cpu_fans_tick()
483 	st->ticks = WF_SMU_CPU_FANS_INTERVAL;  in wf_smu_cpu_fans_tick()
508 	if (temp > st->pid.param.tmax)  in wf_smu_cpu_fans_tick()
511 	new_setpoint = wf_cpu_pid_run(&st->pid, power, temp);  in wf_smu_cpu_fans_tick()
515 	systarget = wf_smu_sys_fans ? wf_smu_sys_fans->pid.target : 0;  in wf_smu_cpu_fans_tick()
516 	systarget = ((((s64)systarget) * (s64)st->scale) >> 12)  in wf_smu_cpu_fans_tick()
517 		+ st->offset;  in wf_smu_cpu_fans_tick()
519 	new_setpoint = max(new_setpoint, st->pid.param.min);  in wf_smu_cpu_fans_tick()
520 	new_setpoint = min(new_setpoint, st->pid.param.max);  in wf_smu_cpu_fans_tick()
524 	if (st->cpu_setpoint == new_setpoint)  in wf_smu_cpu_fans_tick()
526 	st->cpu_setpoint = new_setpoint;  in wf_smu_cpu_fans_tick()
529 		rc = wf_control_set(fan_cpu_main, st->cpu_setpoint);  in wf_smu_cpu_fans_tick()
549 		DBG("wf: creating control loops !\n");  in wf_smu_tick()
556 	if (wf_smu_skipping && --wf_smu_skipping)  in wf_smu_tick()
603 	 * the control loop levels, but we don't want to keep it clear  in wf_smu_tick()
617 	if (fan_cpu_main == NULL && !strcmp(ct->name, "cpu-fan")) {  in wf_smu_new_control()
622 	if (fan_system == NULL && !strcmp(ct->name, "system-fan")) {  in wf_smu_new_control()
627 	if (cpufreq_clamp == NULL && !strcmp(ct->name, "cpufreq-clamp")) {  in wf_smu_new_control()
642 	if (fan_hd == NULL && !strcmp(ct->name, "drive-bay-fan")) {  in wf_smu_new_control()
656 	if (sensor_cpu_power == NULL && !strcmp(sr->name, "cpu-power")) {  in wf_smu_new_sensor()
661 	if (sensor_cpu_temp == NULL && !strcmp(sr->name, "cpu-temp")) {  in wf_smu_new_sensor()
666 	if (sensor_hd_temp == NULL && !strcmp(sr->name, "hd-temp")) {  in wf_smu_new_sensor()
681 		DBG("wf: new control %s detected\n",  in wf_smu_notify()
682 		    ((struct wf_control *)data)->name);  in wf_smu_notify()
688 		    ((struct wf_sensor *)data)->name);  in wf_smu_notify()
711 		wf_smu_mach_model = st->model_id;  in wf_init_pm()
761 	/* Destroy control loops state structures */  in wf_smu_remove()
777 	int rc = -ENODEV;  in wf_smu_init()
808 MODULE_DESCRIPTION("Thermal control logic for iMac G5");