[Intel-gfx] Scaling control for HDMI output from GM45?

[Chris Wilson]

On Sun, 1 May 2011 22:29:56 -0700, Joshua Redstone <redstone at gmail.com> wrote:
> Hi intel-gfx,
> I have a Lenovo T500 laptop with a GM45 graphics chip.   Under Ubuntu
> 11.04 (which shows intel Xorg driver version 2.14.0 in
> /var/log/Xorg.0.log), when I connect an external LCD tv (sony bravia
> 46ex620) to the laptop via HDMI at 1080p, the 1920x1080 image on the
> tv extends beyond the borders of the tv by about 10%.
> What option can I set in the intel driver to tell it to send the raw
> 1920x1080 image without scaling it?

Your TV is overscanning. Either read the manual for your TV to see if
there is a way for it to present the raw signal on the visible portion of
the screen or set up an xrandr transformation matrix to scale the output
similarly.

It may be possible to repurpose the panel fitter to do this (on some
chipsets, i.e. depending upon hardware availability and flexibility) and
so achieve an efficient high quality downscaling, but that will require a
new interface for the ddx to pass the xrandr translation+scale matrix down
into the kernel.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre