[Intel-gfx] Sandy Bridge Desktop - 1920x1080i interlace not working

[Alfonso Fiore]

On Sun, Jan 22, 2012 at 11:40 AM, Daniel Vetter <daniel at ffwll.ch> wrote:
>
> Actually I only need the output of intel_reg_dumper, resolution
> doesn't really matter that much. It just needs to be a HDMI-only
> configuration that works.

Hi Daniel,

here are the tests:

TEST-11
========
Only HDMI connected.
TV set on HDMI input.
Reboot.
The login screen uses the wrong resolution and
it's in the wrong position as usual.
I connected over VNC to login.
Strangely now there is no split screen anymore
(I checked and I'm using 3.2.0-drm-intel-fixes+)
the screen is black and the resolution is 1024x768
(I can see from VNC)
xrandr --output HDMI2 --mode 1024x768 --rate 60.0
(as expected no change since it's the actual res)
xrandr --output HDMI2 --mode 1280x720 --rate 60.0
(the TV does something, but then goes back to black
resolution is correct from VNC)
xrandr --output HDMI2 --mode 1280x720 --rate 50.0
(the TV does something, but then goes back to black
resolution is correct from VNC)
xrandr --output HDMI2 --mode 800x600 --rate 60.3
(the TV does something, but then goes back to black
resolution is correct from VNC)
xrandr --output HDMI2 --mode 800x600 --rate 60.3
(the TV does something, but then goes back to black
resolution is correct from VNC)
xrandr --output HDMI2 --mode 720x480 --rate 59.9
(the TV does something, but then goes back to black
resolution is correct from VNC)
xrandr --output HDMI2 --mode 640x480 --rate 59.9
(the TV does something, but then goes back to black
resolution is correct from VNC)
xrandr --output HDMI2 --mode 640x480 --rate 60.0
(the TV does something, but then goes back to black
resolution is correct from VNC)
I didn't save any dump cause you requested one where HDMI was working
and it never did.
Any idea?
My question is: why I don't even see the split screen anymore
and just the black screen?
So, just to test, I run with 3.0.0-15-generic-pae and indeed
I can see the split screen again. Also, the login screen
is 1024x768 (split) rather than 1280x720 (when I run 3.2.0-drm-intel-fixes+)
In 3.0.0-15-generic-pae, I can see the split screen but xrandr -q
reports way less combinations (1024x768 at 60.0, 800x600 at 60.3, 640x480 at 60).
I tried all three and they all "work" in split screen w/o flickering.
The TV goes never "black".

> It just needs to be a HDMI-only configuration that works.

So if I understand your request correctly, I don't have such situation
with only HDMI.

AGAIN, as soon as I connect the VGA cable the TV is not in split
screen anymore and I can see just fine.
But you already have this test from the previous time so I won't take any log.

>
> Test with the i915 driver (i.e. no nomodeset on the kernel cmdline),
> if you want you can try both VGA cable only and VGA/HDMI but it
> shouldn't matter. xrandr -q output shows only 55.4 and 60.0 for this
> resolution, so I think it doesn't make sense to test anything else.

TEST-12
========
VGA and HDMI connected.
TV set on VGA input.
Reboot.
The login screen is black.
I connected over VNC to login (login screen is 1024x768)

xrandr --output VGA1 --mode 1024x768 --rate 54.4
(nothing changes, as expected)
xrandr --output VGA1 --mode 1024x768 --rate 60.0
bingo. I can see the screen with quite a bit of overscan top and bottom
(exactly as I usually saw it over VGA from XP)

I also tried the same test with only VGA cable connected and it works
the same way.

xrandr --output VGA1 --mode 800x600 --rate 60.3
also works like in windows, with overscan.

I attached logs from 1024x768.

So, to conclude, I think we achieved feature parity over VGA. It's
just a matter
of choosing the right refresh rate...

Do you have any idea about the next step for HDMI?

thank you,
alfonso