Rock 5B FAN Control

#1

Hello, and happy new year!

The fan on my Rock 5B runs quite slowly.
It is connected to the FAN connection.

How can I make the fan speed dependent on the temperature or set it to a fixed larger/higher value?

Armbian 23.11.1 with xfce Desktop and kernel 5.10.110 is installed.

I would be happy to get tips in the right direction!

#2

You should look at the sysfs cooling zones located in /sys/class/thermal/

Also take a look at these gh issues


#3

I have similar question. I am running radxa debian and looking for the file which contains fan speed values of cooling levels for cooling_device4 (pwm_fan).
I want to change Level 1 value from 64 to 72 which works better for me.

Thank you for your help!

#4

That’s contained in the dtb decompile dtb using dtc and change it I’ll provide the links you need

#5

Install dtc

sudo apt install device-tree-compiler

Find dtb in /boot/…
Copy it to ur current dir

dtc -I dtb -O dts -f ./rk3588-rock5b.dtb -o ./rk3588-rock5b.dts

Find and edit the cooling level (example here is before it is compiled just to show u how it looks so don’t copy and paste it)

       fan0: pwm-fan {
                compatible = "pwm-fan";
                #cooling-cells = <2>;
                cooling-levels = <0 64 128 192 255>;
                pwms = <&pwm1 0 10000 0>;
        };

Then put the dtb back together

dtc -I dts -O dtb -f ./rk3588-rock5b.dts -o ./rk3588-rock5b.dtb

Copy it back from where you took it from

#6

Thank you for the information, but I do not have any dtb in the /boot/. Everything I find close to that is some .disabled files in the dtbo folder.

#7

Uhh don’t look at the root of boot, look at boot/dtbs and then rockchip/ as it I don’t remember I don’t use debian and it’s different on arch

#8

I did it. Thanks for your help!

  1. I found dtb-s in /usr/lib/linux-image-5.10.110-27-rockchip/rockchip .
  2. I changed hex value:
    pwm-fan {
    compatible = “pwm-fan”;
    #cooling-cells = <0x02>;
    cooling-levels = <0x00 0x48 0x80 0xc0 0xff>;
    pwms = <0x1a7 0x00 0x2710 0x00>;
    phandle = <0x4b>;
#9

Armbian 23.11.1 bookworm (xfce)
Kernel 5.10.110

Unfortunately my fan problem is not yet solved…

The fan still runs very slowly.
I can set it manually, but the automatic temperature control doesn’t work.
I use this overlay:

/dts-v1/;
/plugin/;
/ {
fragment@0 {
target = <&fan0>;
overlay {
cooling levels = <120 135 150 165 180 195 210 235 255>;
};
};
};

I changed the “policy” file in the /sys/class/thermal/thermal_zone0 folder as “root” from user_space to step_wise.
After a restart it is back to user_space… and the fan is at level 1 (of 8)…

The overlay is also correctly entered in /boot armbianEnv.txt.
The new entry is also present in /boot/overlay-user/.

The access rights for armbianEnv.txt have “1001” as the owner and “123” as the group.

Doesn’t root also have to have access (i.e. become a member of group 123?) so that the armbianEnv is not overwritten by owner 1001 every time after a restart?

How can I add root or xxx@rock5b as a member of group 123 there?

#10

These levels are too low (and obviously made by someone who did not even listen to whether the fan makes any coil whine noise).

#11

Hi incognito
Thanks for the info.

but unfortunately only a half answer…
what values belong in there?

It’s one thing that the values aren’t right.

The bigger problem is that the “policy” file in the “/sys/class/thermal/thermal_zone0” folder is reset to user_space every time you restart, where step_wise should actually be.

It’s understandable that the automatic fan control doesn’t work like this, if that’s the only problem…