KMS question

From: Boszormenyi Zoltan
Date: Thu Apr 13 2017 - 09:03:20 EST


Hi,

how can I disable the behaviour in the KMS drivers
that enables all outputs at once?

It is very annoying that on a POS machine with an
1024x768 LVDS and a 800x480 secondary monitor (both built-in)
the KMS driver wakes up both. Then the framebuffer console
and plymouth use both screens, making the primary output
very odd with only the top-left part used by the boot splash.

I would like the boot splash to be shown only on the primary
output at its full resolution instead of on all outputs using
the smallest common rectangle.

Is there a kernel command line configuration that achieves this?

The device in question uses the gma500 kernel driver but the same
behaviour is observed with the i915 and radeon drivers.

Thanks in advance,
Zoltán Böszörmenyi