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         if (wf_smu_slots_fans)
 
 691                 kfree(wf_smu_cpu_fans);
 
 692         if (wf_smu_drive_fans)
 
 693                 kfree(wf_smu_cpu_fans);
 
 695                 kfree(wf_smu_cpu_fans);
 
 700 static struct platform_driver wf_smu_driver = {
 
 701         .probe = wf_smu_probe,
 
 702         .remove = __devexit_p(wf_smu_remove),
 
 705                 .bus = &platform_bus_type,
 
 710 static int __init wf_smu_init(void)
 
 714         if (machine_is_compatible("PowerMac9,1"))
 
 719                 request_module("windfarm_smu_controls");
 
 720                 request_module("windfarm_smu_sensors");
 
 721                 request_module("windfarm_lm75_sensor");
 
 722                 request_module("windfarm_cpufreq_clamp");
 
 725                 platform_driver_register(&wf_smu_driver);
 
 731 static void __exit wf_smu_exit(void)
 
 734         platform_driver_unregister(&wf_smu_driver);
 
 738 module_init(wf_smu_init);
 
 739 module_exit(wf_smu_exit);
 
 741 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
 
 742 MODULE_DESCRIPTION("Thermal control logic for PowerMac9,1");
 
 743 MODULE_LICENSE("GPL");