Comment 12 for bug 370675

Linux-Libre kernel installed here, runs with no problems (apart from a couple of warning at the beginning of the startup).

To do this, add the following line to your sources (Synaptic -> Settings -> Repositories -> Other software -> Add)
deb http://linux-libre.fsfla.org/pub/linux-libre/planet planet main

Press reload:
Sections -> Kernel and modules

Select:
linux-image-XXXXX-libre-planet
where XXXX is the latest version you see there (currently there is no metapackage which installs the latest version automatically).

Search:
linux-image

Unselect:
linux-image-generic (confirm that you want to uninstall linux-generic)
linux-image
- Note - This will *not* uninstall currently installed non-free kernel, it will simply stop it from updating to newer versions. If for some reason linux-libre will not work for you, you can go back and start with the already installed non-free version and reinstall the metapackages.