How I can upgrade the kernel?
How I can upgrade the kernel to the latest one?
What is your architecture? If you do not know, this command will print it:
$ arch
64-bit, is there any tutorial to do that?
Well, you can follow the instructions for Ubuntu Lucid Lynx (since Trisquel 4 is based on it). Of course, you will want to compile a Linux-libre kernel. Here are the latest source code of it.
Alternatively, you may want to use the beta of Trisquel 4.5 (Slaine). It comes with the newer 2.6.35 kernel (i.e., not the newest).
Also, here is gNewSense how-to:
http://www.gnewsense.org/Documentation/BuildKernel