sys/powerpc/powermac/powermac_thermal.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause
   3  *
   4  * Copyright (c) 2009-2011 Nathan Whitehorn
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #include <sys/param.h>
  30 #include <sys/kernel.h>
  31 #include <sys/lock.h>
  32 #include <sys/mutex.h>
  33 #include <sys/systm.h>
  34
  35 #include <sys/types.h>
  36 #include <sys/kthread.h>
  37 #include <sys/malloc.h>
  38 #include <sys/reboot.h>
  39 #include <sys/sysctl.h>
  40 #include <sys/queue.h>
  41
  42 #include "powermac_thermal.h"
  43
  44 /* A 10 second timer for spinning down fans. */
  45 #define FAN_HYSTERESIS_TIMER    10
  46
  47 static void fan_management_proc(void);
  48 static void pmac_therm_manage_fans(void);
  49
  50 static struct proc *pmac_them_proc;
  51 static int enable_pmac_thermal = 1;
  52
  53 static struct kproc_desc pmac_therm_kp = {
  54         "pmac_thermal",
  55         fan_management_proc,
  56         &pmac_them_proc
  57 };
  58
  59 SYSINIT(pmac_therm_setup, SI_SUB_KTHREAD_IDLE, SI_ORDER_ANY, kproc_start,
  60     &pmac_therm_kp);
  61 SYSCTL_INT(_machdep, OID_AUTO, manage_fans, CTLFLAG_RWTUN,
  62     &enable_pmac_thermal, 1, "Enable automatic fan management");
  63 static MALLOC_DEFINE(M_PMACTHERM, "pmactherm", "Powermac Thermal Management");
  64
  65 struct pmac_fan_le {
  66         struct pmac_fan                 *fan;
  67         int                             last_val;
  68         int                             timer;
  69         SLIST_ENTRY(pmac_fan_le)        entries;
  70 };
  71 struct pmac_sens_le {
  72         struct pmac_therm               *sensor;
  73         int                             last_val;
  74 #define MAX_CRITICAL_COUNT 6
  75         int                             critical_count;
  76         SLIST_ENTRY(pmac_sens_le)       entries;
  77 };
  78 static SLIST_HEAD(pmac_fans, pmac_fan_le) fans = SLIST_HEAD_INITIALIZER(fans);
  79 static SLIST_HEAD(pmac_sensors, pmac_sens_le) sensors =
  80     SLIST_HEAD_INITIALIZER(sensors);
  81
  82 static void
  83 fan_management_proc(void)
  84 {
  85         /* Nothing to manage? */
  86         if (SLIST_EMPTY(&fans))
  87                 kproc_exit(0);
  88
  89         while (1) {
  90                 pmac_therm_manage_fans();
  91                 pause("pmac_therm", hz);
  92         }
  93 }
  94
  95 static void
  96 pmac_therm_manage_fans(void)
  97 {
  98         struct pmac_sens_le *sensor;
  99         struct pmac_fan_le *fan;
 100         int average_excess, max_excess_zone, frac_excess;
 101         int fan_speed;
 102         int nsens, nsens_zone;
 103         int temp;
 104
 105         if (!enable_pmac_thermal)
 106                 return;
 107
 108         /* Read all the sensors */
 109         SLIST_FOREACH(sensor, &sensors, entries) {
 110                 temp = sensor->sensor->read(sensor->sensor);
 111                 if (temp > 0) /* Use the previous temp in case of error */
 112                         sensor->last_val = temp;
 113
 114                 if (sensor->last_val > sensor->sensor->max_temp) {
 115                         sensor->critical_count++;
 116                         printf("WARNING: Current temperature (%s: %d.%d C) "
 117                             "exceeds critical temperature (%d.%d C); "
 118                             "count=%d\n",
 119                             sensor->sensor->name,
 120                             (sensor->last_val - ZERO_C_TO_K) / 10,
 121                             (sensor->last_val - ZERO_C_TO_K) % 10,
 122                             (sensor->sensor->max_temp - ZERO_C_TO_K) / 10,
 123                             (sensor->sensor->max_temp - ZERO_C_TO_K) % 10,
 124                             sensor->critical_count);
 125                         if (sensor->critical_count >= MAX_CRITICAL_COUNT) {
 126                                 printf("WARNING: %s temperature exceeded "
 127                                     "critical temperature %d times in a row; "
 128                                     "shutting down!\n",
 129                                     sensor->sensor->name,
 130                                     sensor->critical_count);
 131                                 shutdown_nice(RB_POWEROFF);
 132                         }
 133                 } else {
 134                         if (sensor->critical_count > 0)
 135                                 sensor->critical_count--;
 136                 }
 137         }
 138
 139         /* Set all the fans */
 140         SLIST_FOREACH(fan, &fans, entries) {
 141                 nsens = nsens_zone = 0;
 142                 average_excess = max_excess_zone = 0;
 143                 SLIST_FOREACH(sensor, &sensors, entries) {
 144                         temp = imin(sensor->last_val,
 145                             sensor->sensor->max_temp);
 146                         frac_excess = (temp -
 147                             sensor->sensor->target_temp)*100 /
 148                             (sensor->sensor->max_temp - temp + 1);
 149                         if (frac_excess < 0)
 150                                 frac_excess = 0;
 151                         if (sensor->sensor->zone == fan->fan->zone) {
 152                                 max_excess_zone = imax(max_excess_zone,
 153                                     frac_excess);
 154                                 nsens_zone++;
 155                         }
 156                         average_excess += frac_excess;
 157                         nsens++;
 158                 }
 159                 average_excess /= nsens;
 160
 161                 /* If there are no sensors in this zone, use the average */
 162                 if (nsens_zone == 0)
 163                         max_excess_zone = average_excess;
 164                 /* No sensors at all? Use default */
 165                 if (nsens == 0) {
 166                         fan->fan->set(fan->fan, fan->fan->default_rpm);
 167                         continue;
 168                 }
 169
 170                 /*
 171                  * Scale the fan linearly in the max temperature in its
 172                  * thermal zone.
 173                  */
 174                 max_excess_zone = imin(max_excess_zone, 100);
 175                 fan_speed = max_excess_zone *
 176                     (fan->fan->max_rpm - fan->fan->min_rpm)/100 +
 177                     fan->fan->min_rpm;
 178                 if (fan_speed >= fan->last_val) {
 179                     fan->timer = FAN_HYSTERESIS_TIMER;
 180                     fan->last_val = fan_speed;
 181                 } else {
 182                     fan->timer--;
 183                     if (fan->timer == 0) {
 184                         fan->last_val = fan_speed;
 185                         fan->timer = FAN_HYSTERESIS_TIMER;
 186                     }
 187                 }
 188                 fan->fan->set(fan->fan, fan->last_val);
 189         }
 190 }
 191
 192 void
 193 pmac_thermal_fan_register(struct pmac_fan *fan)
 194 {
 195         struct pmac_fan_le *list_entry;
 196
 197         list_entry = malloc(sizeof(struct pmac_fan_le), M_PMACTHERM,
 198             M_ZERO | M_WAITOK);
 199         list_entry->fan = fan;
 200
 201         SLIST_INSERT_HEAD(&fans, list_entry, entries);
 202 }
 203
 204 void
 205 pmac_thermal_sensor_register(struct pmac_therm *sensor)
 206 {
 207         struct pmac_sens_le *list_entry;
 208
 209         list_entry = malloc(sizeof(struct pmac_sens_le), M_PMACTHERM,
 210             M_ZERO | M_WAITOK);
 211         list_entry->sensor = sensor;
 212         list_entry->last_val = 0;
 213         list_entry->critical_count = 0;
 214
 215         SLIST_INSERT_HEAD(&sensors, list_entry, entries);
 216 }