EDID override for full RGB?

EDID override for full RGB?

[Tom Horsley]

I'm trying to figure out which bits to flip in the
EDID info for my TV so that the Intel video driver
will be willing to use full RGB as soon as possible
(I get tired of thinking my eyes have gone bad
when I'm booting my system :-).

I built the latest git version of edid-decode,
and I see it printing this info:

  Extended tag: video capability data block
    YCbCr quantization: No Data (0)
    RGB quantization: No Data (0)

If I toggle that "RGB quantization" bit (if I can figure
out which byte it is in :-) will that be the magic
that induces the intel driver to use full range RGB
all the time?

Really no way to get full RGB by default?

[Tom Horsley]

> I built the latest git version of edid-decode,
> and I see it printing this info:
> 
>   Extended tag: video capability data block
>     YCbCr quantization: No Data (0)
>     RGB quantization: No Data (0)
> 
> If I toggle that "RGB quantization" bit (if I can figure
> out which byte it is in :-) will that be the magic
> that induces the intel driver to use full range RGB
> all the time?

I went ahead and tried that, and it didn't work, I
still get limited RGB by default, so I dug up the
kernel sources and started poking around and if I'm
reading them correctly, there is absolutely no way
to get full RGB by default if you are using a mode
that matches any of the standard CEA video modes.

Is this really correct?

Where's my kernel option to override this? :-).

Can we add a user defined extension to EDID to
change the default? (I have to override the EDID
on the kernel command line anyway to fix the
latest gnome stupidities).

Is there a program I could include in the initramfs
and change the setting really early? I certainly can't
run xrandr then.

I'm contemplating writing a program to hack
the built in table of CEA video modes in drm.ko so
the 1920x1080@60HZ won't match...