Dear coreboot community,
tty0_ in #coreboot/#libreboot found a partial fix.
Setting gfx.lvds_dual_channel = 1 is a workaround so that the kernel driver (i915) pickups the right value that coreboot had set. But there are few things to be fixed:
1) No video (fb) during payload(grub) for gm45 (T500) with lcd with dual channel lvds, up to the point where the kernel installs the i915 driver at which point i get working screen. (For single channel lvds controllers all works ok - there is video during payload).
2) There are devices with same model that come both variants (i.e T500) with a single or dual channel lvds . I dont know if there is (currently) way in coreboot (without using the vbios blob) to detect this dynamically (in runtime) instead of setting it in the devicetree.
I am willing to work on this problems, but my knowledge is limited in this area. So, any hints on how to proceed, links to specs/docs, etc are welcome.
-
Pi Van Den Cirkel