fan.c

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/*
 * Copyright 2012 Red Hat Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: Ben Skeggs
 *      Martin Peres
 */

#include "priv.h"

#include <core/object.h>
#include <core/device.h>
#include <subdev/gpio.h>
#include <subdev/timer.h>

int
nouveau_therm_fan_get(struct nouveau_therm *therm)
{
    struct nouveau_therm_priv *priv = (void *)therm;
    struct nouveau_gpio *gpio = nouveau_gpio(therm);
    struct dcb_gpio_func func;
    int card_type = nv_device(therm)->card_type;
    u32 divs, duty;
    int ret;

    if (!priv->fan.pwm_get)
        return -ENODEV;

    ret = gpio->find(gpio, 0, DCB_GPIO_PWM_FAN, 0xff, &func);
    if (ret == 0) {
        ret = priv->fan.pwm_get(therm, func.line, &divs, &duty);
        if (ret == 0 && divs) {
            divs = max(divs, duty);
            if (card_type <= NV_40 || (func.log[0] & 1))
                duty = divs - duty;
            return (duty * 100) / divs;
        }

        return gpio->get(gpio, 0, func.func, func.line) * 100;
    }

    return -ENODEV;
}

int
nouveau_therm_fan_set(struct nouveau_therm *therm, int percent)
{
    struct nouveau_therm_priv *priv = (void *)therm;
    struct nouveau_gpio *gpio = nouveau_gpio(therm);
    struct dcb_gpio_func func;
    int card_type = nv_device(therm)->card_type;
    u32 divs, duty;
    int ret;

    if (priv->fan.mode == FAN_CONTROL_NONE)
        return -EINVAL;

    if (!priv->fan.pwm_set)
        return -ENODEV;

    if (percent < priv->bios_fan.min_duty)
        percent = priv->bios_fan.min_duty;
    if (percent > priv->bios_fan.max_duty)
        percent = priv->bios_fan.max_duty;

    ret = gpio->find(gpio, 0, DCB_GPIO_PWM_FAN, 0xff, &func);
    if (ret == 0) {
        divs = priv->bios_perf_fan.pwm_divisor;
        if (priv->bios_fan.pwm_freq) {
            divs = 1;
            if (priv->fan.pwm_clock)
                divs = priv->fan.pwm_clock(therm);
            divs /= priv->bios_fan.pwm_freq;
        }

        duty = ((divs * percent) + 99) / 100;
        if (card_type <= NV_40 || (func.log[0] & 1))
            duty = divs - duty;

        ret = priv->fan.pwm_set(therm, func.line, divs, duty);
        return ret;
    }

    return -ENODEV;
}

int
nouveau_therm_fan_sense(struct nouveau_therm *therm)
{
    struct nouveau_timer *ptimer = nouveau_timer(therm);
    struct nouveau_gpio *gpio = nouveau_gpio(therm);
    struct dcb_gpio_func func;
    u32 cycles, cur, prev;
    u64 start, end, tach;

    if (gpio->find(gpio, 0, DCB_GPIO_FAN_SENSE, 0xff, &func))
        return -ENODEV;

    /* Time a complete rotation and extrapolate to RPM:
     * When the fan spins, it changes the value of GPIO FAN_SENSE.
     * We get 4 changes (0 -> 1 -> 0 -> 1) per complete rotation.
     */
    start = ptimer->read(ptimer);
    prev = gpio->get(gpio, 0, func.func, func.line);
    cycles = 0;
    do {
        usleep_range(500, 1000); /* supports 0 < rpm < 7500 */

        cur = gpio->get(gpio, 0, func.func, func.line);
        if (prev != cur) {
            if (!start)
                start = ptimer->read(ptimer);
            cycles++;
            prev = cur;
        }
    } while (cycles < 5 && ptimer->read(ptimer) - start < 250000000);
    end = ptimer->read(ptimer);

    if (cycles == 5) {
        tach = (u64)60000000000ULL;
        do_div(tach, (end - start));
        return tach;
    } else
        return 0;
}

int
nouveau_therm_fan_set_mode(struct nouveau_therm *therm,
               enum nouveau_therm_fan_mode mode)
{
    struct nouveau_therm_priv *priv = (void *)therm;

    if (priv->fan.mode == mode)
        return 0;

    if (mode < FAN_CONTROL_NONE || mode >= FAN_CONTROL_NR)
        return -EINVAL;

    switch (mode)
    {
    case FAN_CONTROL_NONE:
        nv_info(therm, "switch fan to no-control mode\n");
        break;
    case FAN_CONTROL_MANUAL:
        nv_info(therm, "switch fan to manual mode\n");
        break;
    case FAN_CONTROL_NR:
        break;
    }

    priv->fan.mode = mode;
    return 0;
}

int
nouveau_therm_fan_user_get(struct nouveau_therm *therm)
{
    return nouveau_therm_fan_get(therm);
}

int
nouveau_therm_fan_user_set(struct nouveau_therm *therm, int percent)
{
    struct nouveau_therm_priv *priv = (void *)therm;

    if (priv->fan.mode != FAN_CONTROL_MANUAL)
        return -EINVAL;

    return nouveau_therm_fan_set(therm, percent);
}

void
nouveau_therm_fan_set_defaults(struct nouveau_therm *therm)
{
    struct nouveau_therm_priv *priv = (void *)therm;

    priv->bios_fan.pwm_freq = 0;
    priv->bios_fan.min_duty = 0;
    priv->bios_fan.max_duty = 100;
}


static void
nouveau_therm_fan_safety_checks(struct nouveau_therm *therm)
{
    struct nouveau_therm_priv *priv = (void *)therm;

    if (priv->bios_fan.min_duty > 100)
        priv->bios_fan.min_duty = 100;
    if (priv->bios_fan.max_duty > 100)
        priv->bios_fan.max_duty = 100;

    if (priv->bios_fan.min_duty > priv->bios_fan.max_duty)
        priv->bios_fan.min_duty = priv->bios_fan.max_duty;
}

int nouveau_fan_pwm_clock_dummy(struct nouveau_therm *therm)
{
    return 1;
}

int
nouveau_therm_fan_ctor(struct nouveau_therm *therm)
{
    struct nouveau_therm_priv *priv = (void *)therm;
    struct nouveau_bios *bios = nouveau_bios(therm);

    nouveau_therm_fan_set_defaults(therm);
    nvbios_perf_fan_parse(bios, &priv->bios_perf_fan);
    if (nvbios_therm_fan_parse(bios, &priv->bios_fan))
        nv_error(therm, "parsing the thermal table failed\n");
    nouveau_therm_fan_safety_checks(therm);

    nouveau_therm_fan_set_mode(therm, FAN_CONTROL_NONE);

    return 0;
}