1/* $NetBSD: nouveau_subdev_therm_fan.c,v 1.2 2015/10/31 09:14:27 mrg Exp $ */
2
3/*
4 * Copyright 2012 Red Hat Inc.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 *
24 * Authors: Ben Skeggs
25 * Martin Peres
26 */
27
28#include <sys/cdefs.h>
29__KERNEL_RCSID(0, "$NetBSD: nouveau_subdev_therm_fan.c,v 1.2 2015/10/31 09:14:27 mrg Exp $");
30
31#include "priv.h"
32
33#include <core/object.h>
34#include <core/device.h>
35
36#include <subdev/gpio.h>
37#include <subdev/timer.h>
38
39static int
40nouveau_fan_update(struct nouveau_fan *fan, bool immediate, int target)
41{
42 struct nouveau_therm *therm = fan->parent;
43 struct nouveau_therm_priv *priv = (void *)therm;
44 struct nouveau_timer *ptimer = nouveau_timer(priv);
45 unsigned long flags;
46 int ret = 0;
47 int duty;
48
49 /* update target fan speed, restricting to allowed range */
50 spin_lock_irqsave(&fan->lock, flags);
51 if (target < 0)
52 target = fan->percent;
53 target = max_t(u8, target, fan->bios.min_duty);
54 target = min_t(u8, target, fan->bios.max_duty);
55 if (fan->percent != target) {
56#if 0 /* XXXMRG one log per second is a little excessive */
57 nv_debug(therm, "FAN target: %d\n", target);
58#endif
59 fan->percent = target;
60 }
61
62 /* check that we're not already at the target duty cycle */
63 duty = fan->get(therm);
64 if (duty == target) {
65 spin_unlock_irqrestore(&fan->lock, flags);
66 return 0;
67 }
68
69 /* smooth out the fanspeed increase/decrease */
70 if (!immediate && duty >= 0) {
71 /* the constant "3" is a rough approximation taken from
72 * nvidia's behaviour.
73 * it is meant to bump the fan speed more incrementally
74 */
75 if (duty < target)
76 duty = min(duty + 3, target);
77 else if (duty > target)
78 duty = max(duty - 3, target);
79 } else {
80 duty = target;
81 }
82
83#if 0 /* XXXMRG one log per second is a little excessive */
84 nv_debug(therm, "FAN update: %d\n", duty);
85#endif
86 ret = fan->set(therm, duty);
87 if (ret) {
88 spin_unlock_irqrestore(&fan->lock, flags);
89 return ret;
90 }
91
92 /* fan speed updated, drop the fan lock before grabbing the
93 * alarm-scheduling lock and risking a deadlock
94 */
95 spin_unlock_irqrestore(&fan->lock, flags);
96
97 /* schedule next fan update, if not at target speed already */
98 if (list_empty(&fan->alarm.head) && target != duty) {
99 u16 bump_period = fan->bios.bump_period;
100 u16 slow_down_period = fan->bios.slow_down_period;
101 u64 delay;
102
103 if (duty > target)
104 delay = slow_down_period;
105 else if (duty == target)
106 delay = min(bump_period, slow_down_period) ;
107 else
108 delay = bump_period;
109
110 ptimer->alarm(ptimer, delay * 1000 * 1000, &fan->alarm);
111 }
112
113 return ret;
114}
115
116static void
117nouveau_fan_alarm(struct nouveau_alarm *alarm)
118{
119 struct nouveau_fan *fan = container_of(alarm, struct nouveau_fan, alarm);
120 nouveau_fan_update(fan, false, -1);
121}
122
123int
124nouveau_therm_fan_get(struct nouveau_therm *therm)
125{
126 struct nouveau_therm_priv *priv = (void *)therm;
127 return priv->fan->get(therm);
128}
129
130int
131nouveau_therm_fan_set(struct nouveau_therm *therm, bool immediate, int percent)
132{
133 struct nouveau_therm_priv *priv = (void *)therm;
134 return nouveau_fan_update(priv->fan, immediate, percent);
135}
136
137int
138nouveau_therm_fan_sense(struct nouveau_therm *therm)
139{
140 struct nouveau_therm_priv *priv = (void *)therm;
141 struct nouveau_timer *ptimer = nouveau_timer(therm);
142 struct nouveau_gpio *gpio = nouveau_gpio(therm);
143 u32 cycles, cur, prev;
144 u64 start, end, tach;
145
146 if (priv->fan->tach.func == DCB_GPIO_UNUSED)
147 return -ENODEV;
148
149 /* Time a complete rotation and extrapolate to RPM:
150 * When the fan spins, it changes the value of GPIO FAN_SENSE.
151 * We get 4 changes (0 -> 1 -> 0 -> 1) per complete rotation.
152 */
153 start = ptimer->read(ptimer);
154 prev = gpio->get(gpio, 0, priv->fan->tach.func, priv->fan->tach.line);
155 cycles = 0;
156 do {
157 usleep_range(500, 1000); /* supports 0 < rpm < 7500 */
158
159 cur = gpio->get(gpio, 0, priv->fan->tach.func, priv->fan->tach.line);
160 if (prev != cur) {
161 if (!start)
162 start = ptimer->read(ptimer);
163 cycles++;
164 prev = cur;
165 }
166 } while (cycles < 5 && ptimer->read(ptimer) - start < 250000000);
167 end = ptimer->read(ptimer);
168
169 if (cycles == 5) {
170 tach = (u64)60000000000ULL;
171 do_div(tach, (end - start));
172 return tach;
173 } else
174 return 0;
175}
176
177int
178nouveau_therm_fan_user_get(struct nouveau_therm *therm)
179{
180 return nouveau_therm_fan_get(therm);
181}
182
183int
184nouveau_therm_fan_user_set(struct nouveau_therm *therm, int percent)
185{
186 struct nouveau_therm_priv *priv = (void *)therm;
187
188 if (priv->mode != NOUVEAU_THERM_CTRL_MANUAL)
189 return -EINVAL;
190
191 return nouveau_therm_fan_set(therm, true, percent);
192}
193
194static void
195nouveau_therm_fan_set_defaults(struct nouveau_therm *therm)
196{
197 struct nouveau_therm_priv *priv = (void *)therm;
198
199 priv->fan->bios.pwm_freq = 0;
200 priv->fan->bios.min_duty = 0;
201 priv->fan->bios.max_duty = 100;
202 priv->fan->bios.bump_period = 500;
203 priv->fan->bios.slow_down_period = 2000;
204 priv->fan->bios.linear_min_temp = 40;
205 priv->fan->bios.linear_max_temp = 85;
206}
207
208static void
209nouveau_therm_fan_safety_checks(struct nouveau_therm *therm)
210{
211 struct nouveau_therm_priv *priv = (void *)therm;
212
213 if (priv->fan->bios.min_duty > 100)
214 priv->fan->bios.min_duty = 100;
215 if (priv->fan->bios.max_duty > 100)
216 priv->fan->bios.max_duty = 100;
217
218 if (priv->fan->bios.min_duty > priv->fan->bios.max_duty)
219 priv->fan->bios.min_duty = priv->fan->bios.max_duty;
220}
221
222int
223nouveau_therm_fan_init(struct nouveau_therm *therm)
224{
225 return 0;
226}
227
228int
229nouveau_therm_fan_fini(struct nouveau_therm *therm, bool suspend)
230{
231 struct nouveau_therm_priv *priv = (void *)therm;
232 struct nouveau_timer *ptimer = nouveau_timer(therm);
233
234 if (suspend)
235 ptimer->alarm_cancel(ptimer, &priv->fan->alarm);
236 return 0;
237}
238
239int
240nouveau_therm_fan_ctor(struct nouveau_therm *therm)
241{
242 struct nouveau_therm_priv *priv = (void *)therm;
243 struct nouveau_gpio *gpio = nouveau_gpio(therm);
244 struct nouveau_bios *bios = nouveau_bios(therm);
245 struct dcb_gpio_func func;
246 int ret;
247
248 /* attempt to locate a drivable fan, and determine control method */
249 ret = gpio->find(gpio, 0, DCB_GPIO_FAN, 0xff, &func);
250 if (ret == 0) {
251 /* FIXME: is this really the place to perform such checks ? */
252 if (func.line != 16 && func.log[0] & DCB_GPIO_LOG_DIR_IN) {
253 nv_debug(therm, "GPIO_FAN is in input mode\n");
254 ret = -EINVAL;
255 } else {
256 ret = nouveau_fanpwm_create(therm, &func);
257 if (ret != 0)
258 ret = nouveau_fantog_create(therm, &func);
259 }
260 }
261
262 /* no controllable fan found, create a dummy fan module */
263 if (ret != 0) {
264 ret = nouveau_fannil_create(therm);
265 if (ret)
266 return ret;
267 }
268
269 nv_info(therm, "FAN control: %s\n", priv->fan->type);
270
271 /* read the current speed, it is useful when resuming */
272 priv->fan->percent = nouveau_therm_fan_get(therm);
273
274 /* attempt to detect a tachometer connection */
275 ret = gpio->find(gpio, 0, DCB_GPIO_FAN_SENSE, 0xff, &priv->fan->tach);
276 if (ret)
277 priv->fan->tach.func = DCB_GPIO_UNUSED;
278
279 /* initialise fan bump/slow update handling */
280 priv->fan->parent = therm;
281 nouveau_alarm_init(&priv->fan->alarm, nouveau_fan_alarm);
282 spin_lock_init(&priv->fan->lock);
283
284 /* other random init... */
285 nouveau_therm_fan_set_defaults(therm);
286 nvbios_perf_fan_parse(bios, &priv->fan->perf);
287 if (nvbios_therm_fan_parse(bios, &priv->fan->bios))
288 nv_error(therm, "parsing the thermal table failed\n");
289 nouveau_therm_fan_safety_checks(therm);
290 return 0;
291}
292