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

[Joshua Redstone]

Hi Chris,
You are right and thanks for the xrandr suggestion.   I tried plugging
my laptop into other tvs (LG and Samsung) and they have a 'just scan'
option and it worked great, which pretty exonerates the intel
chip/driver from being the culprit.  Also, I think the
horizontal/vertical scaling options in the intel GMA widget in windows
is doing basically the same thing as your xrandr suggestion.
I'm returning the Sony tv and switching to LG/Samsung.
Thanks,
Josh

On Sun, May 1, 2011 at 11:30 PM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> 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
>



-- 
Josh