By default, vt(4) gets the "preferred mode" from DRM, when using a DRM
video driver as its backend. The preferred mode is usually the native
screen resolution.
Now, if this mode isn't appropriate, a user can use loader tunables to
select a mode. The tunables are read in the following order:
1. kern.vt.fb.modes.$connector_name
2. kern.vt.fb.default_mode
For example, to set a 1024x768 mode, no matter the connector:
kern.vt.fb.default_mode="1024x768"
To set a 800x600 mode only on the laptop builtin screen:
kern.vt.fb.modes.LVDS-1="800x600"
MFC after: 1 week
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