amd_gpu_fan_ctrl.py

import os
from time import sleep
from datetime import datetime


max_temp = 70
min_temp = 50
delay = 5

hwmonprefix = '/sys/class/hwmon'


def list_hwmons():
    result = []
    for mon in os.listdir(hwmonprefix):
        tempname = os.path.join(hwmonprefix, mon, 'name')
        if os.path.isfile(tempname):
            with open(tempname, 'r') as tempmon:
                drivername = tempmon.read().rstrip('\n')
                if drivername in ['radeon', 'amdgpu']:
                    result.append(os.path.join(hwmonprefix, mon))
    return result


def get_temp(card_num):
    with open(hwmons[card_num] + '/temp1_input') as f:
        for line in f:
            result = round(int(line)/1000)
        f.close()
    return result


def set_fan_speed(card_num, speed):
    with open(hwmons[card_num] + '/pwm1', 'w') as f:
        f.write(str(speed))
        f.close()


def calc_fan_speed(temp):
    if temp < min_temp:
        result = 0
    elif temp > max_temp:
        result = 255
    else:
        result = (temp - min_temp)*100/(max_temp-min_temp)*(255/100)

    if result > 255:
        result = 255

    return round(result)


def set_pwm1_enable(card_num, on_off):
    with open(hwmons[card_num] + '/pwm1_enable', 'w') as f:
        if on_off:
            f.write('1')
        else:
            f.write('2')
        f.close()


hwmons = list_hwmons()

while True:
    try:
        if os.getegid() == 0:
            print('{}'.format(datetime.now().strftime("%Y-%m-%d %H:%M:%S")), flush=True)
            for num in range(0, len(hwmons)):
                try:
                    gpu_temp = get_temp(num)
                    fan_speed = calc_fan_speed(gpu_temp)
                    set_fan_speed(num, fan_speed)
                    print('#{0} : {1}°C -> {2}'.format(num, gpu_temp, fan_speed), flush=True)
                except:
                    set_pwm1_enable(num, True)
                    print('#{} pwm1_enable set to 1 (manual)'.format(num), flush=True)
                    continue
        else:
            print('please run this script under root', flush=True)
            break
        sleep(delay)
    except KeyboardInterrupt:
        print('\n')
        if os.getegid() == 0:
            for num in range(0, len(hwmons)):
                set_pwm1_enable(num, False)
                print('#{} pwm1_enable set to 2 (auto)'.format(num), flush=True)
        break