xref: /freebsd/sys/powerpc/powermac/powermac_thermal.c (revision fdafd315ad0d0f28a11b9fb4476a9ab059c62b92)
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
fan_management_proc(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
pmac_therm_manage_fans(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
pmac_thermal_fan_register(struct pmac_fan * fan)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
pmac_thermal_sensor_register(struct pmac_therm * sensor)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 }
217