Coreboot, Gentoo, and the Thinkpad X201 Fan
The Blue Pill and the X201!
Coreboot is not able to control the fan in the ThinkPad X201. After flashing the bios chip with Coreboot, you will need to control your fan with something like thinkfan. Installing Gentoo, especially compiling the system, uses a good amount of cpu power which in turn generates heat. You will want to do the following when installing Gentoo to get the fan going:
$ touch /etc/modprobe.d/thinkpad_acpi.conf
$ echo 'options thinkpad_acpi fan_control=1' > /etc/modprobe.d/thinkpad_acpi.conf
$ rmmod thinkpad_acpi
$ modprobe thinkpad_acpi
$ echo level 7 > /proc/acpi/ibm/fan
Next make sure that it is running properly. You should also be able to hear it!
$ cat /proc/acpi/ibm/fan
commands: enable, disable
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