It's not in libreboot yet, but it will be soon.
However, it's possible to build a coreboot ROM for T60 that is blob-free,
with native graphics instead of VGA option ROM (VBIOS), and with non-free
microcode updates removed (not included in ROM).
It also has backlight support (Fn+Home and Fn+End).
The source code in question is still coreboot, but work on the next libreboot
release is well underway, which will have these changes.
X60 is also improved: backlight controls! (Fn+Home and Fn+End)
See here for more details:
http://libreboot.org/howto.html#x60_native_notes
http://libreboot.org/howto.html#t60_native_notes
- these are for coreboot, but the changes there will be in next libreboot
release. stay tuned!
