Add a new ioctl to vt to make it possible to export RGB offsets
set by vt drivers. This is needed to fix colors on X and Mesa
on some machines, especially on modern PowerPC64 BE ones.
With the appropriate changes in SCFB, to use this ioctl to find
out the correct RGB offsets, this fixes wrong colors on Talos II
and Blackbird, when used with their built-in video cards.
Reviewed by: alfredo
Sponsored by: Instituto de Pesquisas Eldorado (eldorado.org.br)
Differential Revision: https://reviews.freebsd.org/D29000
These ones were unambiguous cases where the Foundation was the only
listed copyright holder (in the associated license block).
Sponsored by: The FreeBSD Foundation
Implement vt_vbefb to support Vesa Bios Extensions (VBE) framebuffer with VT.
vt_vbefb is built based on vt_efifb and is assuming similar data for
initialization, use MODINFOMD_VBE_FB to identify the structure vbe_fb
in kernel metadata.
struct vbe_fb, is populated by boot loader, and is passed to kernel via
metadata payload.
Differential Revision: https://reviews.freebsd.org/D27373
