e017607673a56420aad206e05380763a07c18ead
[pandora-kernel.git] / drivers / gpu / drm / nouveau / nvkm / subdev / therm / fan.c
1 /*
2  * Copyright 2012 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Ben Skeggs
23  *          Martin Peres
24  */
25 #include "priv.h"
26
27 #include <subdev/bios/fan.h>
28 #include <subdev/gpio.h>
29 #include <subdev/timer.h>
30
31 static int
32 nvkm_fan_update(struct nvkm_fan *fan, bool immediate, int target)
33 {
34         struct nvkm_therm_priv *therm = (void *)fan->parent;
35         struct nvkm_subdev *subdev = &therm->base.subdev;
36         struct nvkm_timer *tmr = subdev->device->timer;
37         unsigned long flags;
38         int ret = 0;
39         int duty;
40
41         /* update target fan speed, restricting to allowed range */
42         spin_lock_irqsave(&fan->lock, flags);
43         if (target < 0)
44                 target = fan->percent;
45         target = max_t(u8, target, fan->bios.min_duty);
46         target = min_t(u8, target, fan->bios.max_duty);
47         if (fan->percent != target) {
48                 nvkm_debug(subdev, "FAN target: %d\n", target);
49                 fan->percent = target;
50         }
51
52         /* check that we're not already at the target duty cycle */
53         duty = fan->get(&therm->base);
54         if (duty == target) {
55                 spin_unlock_irqrestore(&fan->lock, flags);
56                 return 0;
57         }
58
59         /* smooth out the fanspeed increase/decrease */
60         if (!immediate && duty >= 0) {
61                 /* the constant "3" is a rough approximation taken from
62                  * nvidia's behaviour.
63                  * it is meant to bump the fan speed more incrementally
64                  */
65                 if (duty < target)
66                         duty = min(duty + 3, target);
67                 else if (duty > target)
68                         duty = max(duty - 3, target);
69         } else {
70                 duty = target;
71         }
72
73         nvkm_debug(subdev, "FAN update: %d\n", duty);
74         ret = fan->set(&therm->base, duty);
75         if (ret) {
76                 spin_unlock_irqrestore(&fan->lock, flags);
77                 return ret;
78         }
79
80         /* fan speed updated, drop the fan lock before grabbing the
81          * alarm-scheduling lock and risking a deadlock
82          */
83         spin_unlock_irqrestore(&fan->lock, flags);
84
85         /* schedule next fan update, if not at target speed already */
86         if (list_empty(&fan->alarm.head) && target != duty) {
87                 u16 bump_period = fan->bios.bump_period;
88                 u16 slow_down_period = fan->bios.slow_down_period;
89                 u64 delay;
90
91                 if (duty > target)
92                         delay = slow_down_period;
93                 else if (duty == target)
94                         delay = min(bump_period, slow_down_period) ;
95                 else
96                         delay = bump_period;
97
98                 tmr->alarm(tmr, delay * 1000 * 1000, &fan->alarm);
99         }
100
101         return ret;
102 }
103
104 static void
105 nvkm_fan_alarm(struct nvkm_alarm *alarm)
106 {
107         struct nvkm_fan *fan = container_of(alarm, struct nvkm_fan, alarm);
108         nvkm_fan_update(fan, false, -1);
109 }
110
111 int
112 nvkm_therm_fan_get(struct nvkm_therm *obj)
113 {
114         struct nvkm_therm_priv *therm = container_of(obj, typeof(*therm), base);
115         return therm->fan->get(&therm->base);
116 }
117
118 int
119 nvkm_therm_fan_set(struct nvkm_therm *obj, bool immediate, int percent)
120 {
121         struct nvkm_therm_priv *therm = container_of(obj, typeof(*therm), base);
122         return nvkm_fan_update(therm->fan, immediate, percent);
123 }
124
125 int
126 nvkm_therm_fan_sense(struct nvkm_therm *obj)
127 {
128         struct nvkm_therm_priv *therm = container_of(obj, typeof(*therm), base);
129         struct nvkm_device *device = therm->base.subdev.device;
130         struct nvkm_timer *tmr = device->timer;
131         struct nvkm_gpio *gpio = device->gpio;
132         u32 cycles, cur, prev;
133         u64 start, end, tach;
134
135         if (therm->fan->tach.func == DCB_GPIO_UNUSED)
136                 return -ENODEV;
137
138         /* Time a complete rotation and extrapolate to RPM:
139          * When the fan spins, it changes the value of GPIO FAN_SENSE.
140          * We get 4 changes (0 -> 1 -> 0 -> 1) per complete rotation.
141          */
142         start = tmr->read(tmr);
143         prev = nvkm_gpio_get(gpio, 0, therm->fan->tach.func,
144                                       therm->fan->tach.line);
145         cycles = 0;
146         do {
147                 usleep_range(500, 1000); /* supports 0 < rpm < 7500 */
148
149                 cur = nvkm_gpio_get(gpio, 0, therm->fan->tach.func,
150                                              therm->fan->tach.line);
151                 if (prev != cur) {
152                         if (!start)
153                                 start = tmr->read(tmr);
154                         cycles++;
155                         prev = cur;
156                 }
157         } while (cycles < 5 && tmr->read(tmr) - start < 250000000);
158         end = tmr->read(tmr);
159
160         if (cycles == 5) {
161                 tach = (u64)60000000000ULL;
162                 do_div(tach, (end - start));
163                 return tach;
164         } else
165                 return 0;
166 }
167
168 int
169 nvkm_therm_fan_user_get(struct nvkm_therm *obj)
170 {
171         struct nvkm_therm_priv *therm = container_of(obj, typeof(*therm), base);
172         return nvkm_therm_fan_get(&therm->base);
173 }
174
175 int
176 nvkm_therm_fan_user_set(struct nvkm_therm *obj, int percent)
177 {
178         struct nvkm_therm_priv *therm = container_of(obj, typeof(*therm), base);
179
180         if (therm->mode != NVKM_THERM_CTRL_MANUAL)
181                 return -EINVAL;
182
183         return nvkm_therm_fan_set(&therm->base, true, percent);
184 }
185
186 static void
187 nvkm_therm_fan_set_defaults(struct nvkm_therm *obj)
188 {
189         struct nvkm_therm_priv *therm = container_of(obj, typeof(*therm), base);
190
191         therm->fan->bios.pwm_freq = 0;
192         therm->fan->bios.min_duty = 0;
193         therm->fan->bios.max_duty = 100;
194         therm->fan->bios.bump_period = 500;
195         therm->fan->bios.slow_down_period = 2000;
196         therm->fan->bios.linear_min_temp = 40;
197         therm->fan->bios.linear_max_temp = 85;
198 }
199
200 static void
201 nvkm_therm_fan_safety_checks(struct nvkm_therm *obj)
202 {
203         struct nvkm_therm_priv *therm = container_of(obj, typeof(*therm), base);
204
205         if (therm->fan->bios.min_duty > 100)
206                 therm->fan->bios.min_duty = 100;
207         if (therm->fan->bios.max_duty > 100)
208                 therm->fan->bios.max_duty = 100;
209
210         if (therm->fan->bios.min_duty > therm->fan->bios.max_duty)
211                 therm->fan->bios.min_duty = therm->fan->bios.max_duty;
212 }
213
214 int
215 nvkm_therm_fan_init(struct nvkm_therm *obj)
216 {
217         return 0;
218 }
219
220 int
221 nvkm_therm_fan_fini(struct nvkm_therm *obj, bool suspend)
222 {
223         struct nvkm_therm_priv *therm = container_of(obj, typeof(*therm), base);
224         struct nvkm_timer *tmr = nvkm_timer(therm);
225
226         if (suspend)
227                 tmr->alarm_cancel(tmr, &therm->fan->alarm);
228         return 0;
229 }
230
231 int
232 nvkm_therm_fan_ctor(struct nvkm_therm *obj)
233 {
234         struct nvkm_therm_priv *therm = container_of(obj, typeof(*therm), base);
235         struct nvkm_subdev *subdev = &therm->base.subdev;
236         struct nvkm_device *device = subdev->device;
237         struct nvkm_gpio *gpio = device->gpio;
238         struct nvkm_bios *bios = device->bios;
239         struct dcb_gpio_func func;
240         int ret;
241
242         /* attempt to locate a drivable fan, and determine control method */
243         ret = nvkm_gpio_find(gpio, 0, DCB_GPIO_FAN, 0xff, &func);
244         if (ret == 0) {
245                 /* FIXME: is this really the place to perform such checks ? */
246                 if (func.line != 16 && func.log[0] & DCB_GPIO_LOG_DIR_IN) {
247                         nvkm_debug(subdev, "GPIO_FAN is in input mode\n");
248                         ret = -EINVAL;
249                 } else {
250                         ret = nvkm_fanpwm_create(&therm->base, &func);
251                         if (ret != 0)
252                                 ret = nvkm_fantog_create(&therm->base, &func);
253                 }
254         }
255
256         /* no controllable fan found, create a dummy fan module */
257         if (ret != 0) {
258                 ret = nvkm_fannil_create(&therm->base);
259                 if (ret)
260                         return ret;
261         }
262
263         nvkm_debug(subdev, "FAN control: %s\n", therm->fan->type);
264
265         /* read the current speed, it is useful when resuming */
266         therm->fan->percent = nvkm_therm_fan_get(&therm->base);
267
268         /* attempt to detect a tachometer connection */
269         ret = nvkm_gpio_find(gpio, 0, DCB_GPIO_FAN_SENSE, 0xff,
270                              &therm->fan->tach);
271         if (ret)
272                 therm->fan->tach.func = DCB_GPIO_UNUSED;
273
274         /* initialise fan bump/slow update handling */
275         therm->fan->parent = &therm->base;
276         nvkm_alarm_init(&therm->fan->alarm, nvkm_fan_alarm);
277         spin_lock_init(&therm->fan->lock);
278
279         /* other random init... */
280         nvkm_therm_fan_set_defaults(&therm->base);
281         nvbios_perf_fan_parse(bios, &therm->fan->perf);
282         if (!nvbios_fan_parse(bios, &therm->fan->bios)) {
283                 nvkm_debug(subdev, "parsing the fan table failed\n");
284                 if (nvbios_therm_fan_parse(bios, &therm->fan->bios))
285                         nvkm_error(subdev, "parsing both fan tables failed\n");
286         }
287         nvkm_therm_fan_safety_checks(&therm->base);
288         return 0;
289 }