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
nvkm_fan_update(struct nvkm_fan * fan,bool immediate,int target)32 nvkm_fan_update(struct nvkm_fan *fan, bool immediate, int target)
33 {
34 struct nvkm_therm *therm = fan->parent;
35 struct nvkm_subdev *subdev = &therm->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);
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, 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 (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 nvkm_timer_alarm(tmr, delay * 1000 * 1000, &fan->alarm);
99 }
100
101 return ret;
102 }
103
104 static void
nvkm_fan_alarm(struct nvkm_alarm * alarm)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
nvkm_therm_fan_get(struct nvkm_therm * therm)112 nvkm_therm_fan_get(struct nvkm_therm *therm)
113 {
114 return therm->fan->get(therm);
115 }
116
117 int
nvkm_therm_fan_set(struct nvkm_therm * therm,bool immediate,int percent)118 nvkm_therm_fan_set(struct nvkm_therm *therm, bool immediate, int percent)
119 {
120 return nvkm_fan_update(therm->fan, immediate, percent);
121 }
122
123 int
nvkm_therm_fan_sense(struct nvkm_therm * therm)124 nvkm_therm_fan_sense(struct nvkm_therm *therm)
125 {
126 struct nvkm_device *device = therm->subdev.device;
127 struct nvkm_timer *tmr = device->timer;
128 struct nvkm_gpio *gpio = device->gpio;
129 u32 cycles, cur, prev;
130 u64 start, end, tach;
131
132 if (therm->func->fan_sense)
133 return therm->func->fan_sense(therm);
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 = nvkm_timer_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 = nvkm_timer_read(tmr);
154 cycles++;
155 prev = cur;
156 }
157 } while (cycles < 5 && nvkm_timer_read(tmr) - start < 250000000);
158 end = nvkm_timer_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
nvkm_therm_fan_user_get(struct nvkm_therm * therm)169 nvkm_therm_fan_user_get(struct nvkm_therm *therm)
170 {
171 return nvkm_therm_fan_get(therm);
172 }
173
174 int
nvkm_therm_fan_user_set(struct nvkm_therm * therm,int percent)175 nvkm_therm_fan_user_set(struct nvkm_therm *therm, int percent)
176 {
177 if (therm->mode != NVKM_THERM_CTRL_MANUAL)
178 return -EINVAL;
179
180 return nvkm_therm_fan_set(therm, true, percent);
181 }
182
183 static void
nvkm_therm_fan_set_defaults(struct nvkm_therm * therm)184 nvkm_therm_fan_set_defaults(struct nvkm_therm *therm)
185 {
186 therm->fan->bios.pwm_freq = 0;
187 therm->fan->bios.min_duty = 0;
188 therm->fan->bios.max_duty = 100;
189 therm->fan->bios.bump_period = 500;
190 therm->fan->bios.slow_down_period = 2000;
191 therm->fan->bios.linear_min_temp = 40;
192 therm->fan->bios.linear_max_temp = 85;
193 }
194
195 static void
nvkm_therm_fan_safety_checks(struct nvkm_therm * therm)196 nvkm_therm_fan_safety_checks(struct nvkm_therm *therm)
197 {
198 if (therm->fan->bios.min_duty > 100)
199 therm->fan->bios.min_duty = 100;
200 if (therm->fan->bios.max_duty > 100)
201 therm->fan->bios.max_duty = 100;
202
203 if (therm->fan->bios.min_duty > therm->fan->bios.max_duty)
204 therm->fan->bios.min_duty = therm->fan->bios.max_duty;
205 }
206
207 int
nvkm_therm_fan_init(struct nvkm_therm * therm)208 nvkm_therm_fan_init(struct nvkm_therm *therm)
209 {
210 return 0;
211 }
212
213 int
nvkm_therm_fan_fini(struct nvkm_therm * therm,bool suspend)214 nvkm_therm_fan_fini(struct nvkm_therm *therm, bool suspend)
215 {
216 struct nvkm_timer *tmr = therm->subdev.device->timer;
217 if (suspend)
218 nvkm_timer_alarm(tmr, 0, &therm->fan->alarm);
219 return 0;
220 }
221
222 int
nvkm_therm_fan_ctor(struct nvkm_therm * therm)223 nvkm_therm_fan_ctor(struct nvkm_therm *therm)
224 {
225 struct nvkm_subdev *subdev = &therm->subdev;
226 struct nvkm_device *device = subdev->device;
227 struct nvkm_gpio *gpio = device->gpio;
228 struct nvkm_bios *bios = device->bios;
229 struct dcb_gpio_func func;
230 int ret;
231
232 /* attempt to locate a drivable fan, and determine control method */
233 ret = nvkm_gpio_find(gpio, 0, DCB_GPIO_FAN, 0xff, &func);
234 if (ret == 0) {
235 /* FIXME: is this really the place to perform such checks ? */
236 if (func.line != 16 && func.log[0] & DCB_GPIO_LOG_DIR_IN) {
237 nvkm_debug(subdev, "GPIO_FAN is in input mode\n");
238 ret = -EINVAL;
239 } else {
240 ret = nvkm_fanpwm_create(therm, &func);
241 if (ret != 0)
242 ret = nvkm_fantog_create(therm, &func);
243 }
244 }
245
246 /* no controllable fan found, create a dummy fan module */
247 if (ret != 0) {
248 ret = nvkm_fannil_create(therm);
249 if (ret)
250 return ret;
251 }
252
253 nvkm_debug(subdev, "FAN control: %s\n", therm->fan->type);
254
255 /* read the current speed, it is useful when resuming */
256 therm->fan->percent = nvkm_therm_fan_get(therm);
257
258 /* attempt to detect a tachometer connection */
259 ret = nvkm_gpio_find(gpio, 0, DCB_GPIO_FAN_SENSE, 0xff,
260 &therm->fan->tach);
261 if (ret)
262 therm->fan->tach.func = DCB_GPIO_UNUSED;
263
264 /* initialise fan bump/slow update handling */
265 therm->fan->parent = therm;
266 nvkm_alarm_init(&therm->fan->alarm, nvkm_fan_alarm);
267 spin_lock_init(&therm->fan->lock);
268
269 /* other random init... */
270 nvkm_therm_fan_set_defaults(therm);
271 nvbios_perf_fan_parse(bios, &therm->fan->perf);
272 if (!nvbios_fan_parse(bios, &therm->fan->bios)) {
273 nvkm_debug(subdev, "parsing the fan table failed\n");
274 if (nvbios_therm_fan_parse(bios, &therm->fan->bios))
275 nvkm_error(subdev, "parsing both fan tables failed\n");
276 }
277 nvkm_therm_fan_safety_checks(therm);
278 return 0;
279 }
280