1 /* $NetBSD: nouveau_nvkm_subdev_therm_fan.c,v 1.4 2021/12/19 11:34:46 riastradh 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 #include <sys/cdefs.h> 28 __KERNEL_RCSID(0, "$NetBSD: nouveau_nvkm_subdev_therm_fan.c,v 1.4 2021/12/19 11:34:46 riastradh Exp $"); 29 30 #include "priv.h" 31 32 #include <subdev/bios/fan.h> 33 #include <subdev/gpio.h> 34 #include <subdev/timer.h> 35 36 static int 37 nvkm_fan_update(struct nvkm_fan *fan, bool immediate, int target) 38 { 39 struct nvkm_therm *therm = fan->parent; 40 struct nvkm_subdev *subdev = &therm->subdev; 41 struct nvkm_timer *tmr = subdev->device->timer; 42 unsigned long flags; 43 int ret = 0; 44 int duty; 45 46 /* update target fan speed, restricting to allowed range */ 47 spin_lock_irqsave(&fan->lock, flags); 48 if (target < 0) 49 target = fan->percent; 50 target = max_t(u8, target, fan->bios.min_duty); 51 target = min_t(u8, target, fan->bios.max_duty); 52 if (fan->percent != target) { 53 #if 0 /* XXXMRG one log per second is a little excessive */ 54 nvkm_debug(subdev, "FAN target: %d\n", target); 55 #endif 56 fan->percent = target; 57 } 58 59 /* check that we're not already at the target duty cycle */ 60 duty = fan->get(therm); 61 if (duty == target) { 62 spin_unlock_irqrestore(&fan->lock, flags); 63 return 0; 64 } 65 66 /* smooth out the fanspeed increase/decrease */ 67 if (!immediate && duty >= 0) { 68 /* the constant "3" is a rough approximation taken from 69 * nvidia's behaviour. 70 * it is meant to bump the fan speed more incrementally 71 */ 72 if (duty < target) 73 duty = min(duty + 3, target); 74 else if (duty > target) 75 duty = max(duty - 3, target); 76 } else { 77 duty = target; 78 } 79 80 #if 0 /* XXXMRG one log per second is a little excessive */ 81 nvkm_debug(subdev, "FAN update: %d\n", duty); 82 #endif 83 ret = fan->set(therm, duty); 84 if (ret) { 85 spin_unlock_irqrestore(&fan->lock, flags); 86 return ret; 87 } 88 89 /* fan speed updated, drop the fan lock before grabbing the 90 * alarm-scheduling lock and risking a deadlock 91 */ 92 spin_unlock_irqrestore(&fan->lock, flags); 93 94 /* schedule next fan update, if not at target speed already */ 95 if (target != duty) { 96 u16 bump_period = fan->bios.bump_period; 97 u16 slow_down_period = fan->bios.slow_down_period; 98 u64 delay; 99 100 if (duty > target) 101 delay = slow_down_period; 102 else if (duty == target) 103 delay = min(bump_period, slow_down_period) ; 104 else 105 delay = bump_period; 106 107 nvkm_timer_alarm(tmr, delay * 1000 * 1000, &fan->alarm); 108 } 109 110 return ret; 111 } 112 113 static void 114 nvkm_fan_alarm(struct nvkm_alarm *alarm) 115 { 116 struct nvkm_fan *fan = container_of(alarm, struct nvkm_fan, alarm); 117 nvkm_fan_update(fan, false, -1); 118 } 119 120 int 121 nvkm_therm_fan_get(struct nvkm_therm *therm) 122 { 123 return therm->fan->get(therm); 124 } 125 126 int 127 nvkm_therm_fan_set(struct nvkm_therm *therm, bool immediate, int percent) 128 { 129 return nvkm_fan_update(therm->fan, immediate, percent); 130 } 131 132 int 133 nvkm_therm_fan_sense(struct nvkm_therm *therm) 134 { 135 struct nvkm_device *device = therm->subdev.device; 136 struct nvkm_timer *tmr = device->timer; 137 struct nvkm_gpio *gpio = device->gpio; 138 u32 cycles, cur, prev; 139 u64 start, end, tach; 140 141 if (therm->func->fan_sense) 142 return therm->func->fan_sense(therm); 143 144 if (therm->fan->tach.func == DCB_GPIO_UNUSED) 145 return -ENODEV; 146 147 /* Time a complete rotation and extrapolate to RPM: 148 * When the fan spins, it changes the value of GPIO FAN_SENSE. 149 * We get 4 changes (0 -> 1 -> 0 -> 1) per complete rotation. 150 */ 151 start = nvkm_timer_read(tmr); 152 prev = nvkm_gpio_get(gpio, 0, therm->fan->tach.func, 153 therm->fan->tach.line); 154 cycles = 0; 155 do { 156 usleep_range(500, 1000); /* supports 0 < rpm < 7500 */ 157 158 cur = nvkm_gpio_get(gpio, 0, therm->fan->tach.func, 159 therm->fan->tach.line); 160 if (prev != cur) { 161 if (!start) 162 start = nvkm_timer_read(tmr); 163 cycles++; 164 prev = cur; 165 } 166 } while (cycles < 5 && nvkm_timer_read(tmr) - start < 250000000); 167 end = nvkm_timer_read(tmr); 168 169 if (cycles == 5) { 170 tach = (u64)60000000000ULL; 171 do_div(tach, (end - start)); 172 return tach; 173 } else 174 return 0; 175 } 176 177 int 178 nvkm_therm_fan_user_get(struct nvkm_therm *therm) 179 { 180 return nvkm_therm_fan_get(therm); 181 } 182 183 int 184 nvkm_therm_fan_user_set(struct nvkm_therm *therm, int percent) 185 { 186 if (therm->mode != NVKM_THERM_CTRL_MANUAL) 187 return -EINVAL; 188 189 return nvkm_therm_fan_set(therm, true, percent); 190 } 191 192 static void 193 nvkm_therm_fan_set_defaults(struct nvkm_therm *therm) 194 { 195 therm->fan->bios.pwm_freq = 0; 196 therm->fan->bios.min_duty = 0; 197 therm->fan->bios.max_duty = 100; 198 therm->fan->bios.bump_period = 500; 199 therm->fan->bios.slow_down_period = 2000; 200 therm->fan->bios.linear_min_temp = 40; 201 therm->fan->bios.linear_max_temp = 85; 202 } 203 204 static void 205 nvkm_therm_fan_safety_checks(struct nvkm_therm *therm) 206 { 207 if (therm->fan->bios.min_duty > 100) 208 therm->fan->bios.min_duty = 100; 209 if (therm->fan->bios.max_duty > 100) 210 therm->fan->bios.max_duty = 100; 211 212 if (therm->fan->bios.min_duty > therm->fan->bios.max_duty) 213 therm->fan->bios.min_duty = therm->fan->bios.max_duty; 214 } 215 216 int 217 nvkm_therm_fan_init(struct nvkm_therm *therm) 218 { 219 return 0; 220 } 221 222 int 223 nvkm_therm_fan_fini(struct nvkm_therm *therm, bool suspend) 224 { 225 struct nvkm_timer *tmr = therm->subdev.device->timer; 226 if (suspend) 227 nvkm_timer_alarm(tmr, 0, &therm->fan->alarm); 228 return 0; 229 } 230 231 void 232 nvkm_therm_fan_dtor(struct nvkm_therm *therm) 233 { 234 if (therm->fan->dtor) 235 therm->fan->dtor(therm->fan); 236 spin_lock_destroy(&therm->fan->lock); 237 } 238 239 int 240 nvkm_therm_fan_ctor(struct nvkm_therm *therm) 241 { 242 struct nvkm_subdev *subdev = &therm->subdev; 243 struct nvkm_device *device = subdev->device; 244 struct nvkm_gpio *gpio = device->gpio; 245 struct nvkm_bios *bios = device->bios; 246 struct dcb_gpio_func func; 247 int ret; 248 249 /* attempt to locate a drivable fan, and determine control method */ 250 ret = nvkm_gpio_find(gpio, 0, DCB_GPIO_FAN, 0xff, &func); 251 if (ret == 0) { 252 /* FIXME: is this really the place to perform such checks ? */ 253 if (func.line != 16 && func.log[0] & DCB_GPIO_LOG_DIR_IN) { 254 nvkm_debug(subdev, "GPIO_FAN is in input mode\n"); 255 ret = -EINVAL; 256 } else { 257 ret = nvkm_fanpwm_create(therm, &func); 258 if (ret != 0) 259 ret = nvkm_fantog_create(therm, &func); 260 } 261 } 262 263 /* no controllable fan found, create a dummy fan module */ 264 if (ret != 0) { 265 ret = nvkm_fannil_create(therm); 266 if (ret) 267 return ret; 268 } 269 270 nvkm_debug(subdev, "FAN control: %s\n", therm->fan->type); 271 272 /* read the current speed, it is useful when resuming */ 273 therm->fan->percent = nvkm_therm_fan_get(therm); 274 275 /* attempt to detect a tachometer connection */ 276 ret = nvkm_gpio_find(gpio, 0, DCB_GPIO_FAN_SENSE, 0xff, 277 &therm->fan->tach); 278 if (ret) 279 therm->fan->tach.func = DCB_GPIO_UNUSED; 280 281 /* initialise fan bump/slow update handling */ 282 therm->fan->parent = therm; 283 nvkm_alarm_init(&therm->fan->alarm, nvkm_fan_alarm); 284 spin_lock_init(&therm->fan->lock); 285 286 /* other random init... */ 287 nvkm_therm_fan_set_defaults(therm); 288 nvbios_perf_fan_parse(bios, &therm->fan->perf); 289 if (!nvbios_fan_parse(bios, &therm->fan->bios)) { 290 nvkm_debug(subdev, "parsing the fan table failed\n"); 291 if (nvbios_therm_fan_parse(bios, &therm->fan->bios)) 292 nvkm_error(subdev, "parsing both fan tables failed\n"); 293 } 294 nvkm_therm_fan_safety_checks(therm); 295 return 0; 296 } 297
Indexes created Sat Sep 27 22:09:54 GMT 2025