[PATCH 2/2] drm/radeon/kms: enable underscan option for digital connectors

[Alex Deucher]

2010/8/8 Marius Gröger <marius.groeger at googlemail.com>:
> Am 08.08.2010 18:22, wrote Alex Deucher:
>>>
>>> Also, I kind of was hoping that once I could use 1280x720 for both the
>>> console and the X screen, it would would allow me to switch between the
>>> two
>>> transparently. Instead, the TV takes notice of the switch and needs some
>>> extra syncing time. Is this expected behaviour?
>>
>> You mean switching underscan off and on or a VT switch?  The hw has to
>> reprogram the mode when it changes the underscan.  As for a VT switch,
>> it should just be changing the crtc base, but IIRC there was a bug
>> where X and the console used slightly different modes in some cases.
>
> VT switch. I use video=1280x720 at 50 on the command line and select the
> corresponding EDID resolution within X. Is this bug still pending or is my
> scenario supposed to work?

You may be seeing this issue:
http://lists.x.org/archives/xorg-devel/2010-August/011743.html

Alex