Something still seems to be wrong with these edid files:

[    4.978469] [drm:edid_load [drm]] *ERROR* Size of EDID firmware "edid/1280x800_60.00.bin" is invalid (expected 6272, got 130

Okay, I figured it out - some of the tooling didn't like the _60.00 part of 1280x800_60.00.

Removing this, I was able to build a working edid file.

I added the package to hardware.firmware, and after adding boot.kernelParams = [ "drm.edid_firmware=edid/1280x800.bin"];, qemu successfully booted up in the desired resolution 🎉

Should this append "Modeline " to the front? it seems kind of redundant to specify it, only makes sense if you're parsing an xorg file.

Plus is there much reason to make/install the already included .bin files?

Maybe a flag includeDefaults = true would make sense.

I'm not sure if it's necessary - right now, this consumes the output of the cvt command:

$ cvt 1024 768 60
# 1024x768 59.92 Hz (CVT 0.79M3) hsync: 47.82 kHz; pclk: 63.50 MHz
Modeline "1024x768_60.00"   63.50  1024 1072 1176 1328  768 771 775 798 -hsync +vsync

Shouldn't this package actually install the edid-generator script as well @flokli? That was my expectation.
It seems like it would be useful to couple this with a nixos module that can use it with the cvt command from xorg.xorgserver to generate a custom EDID from a list of modes and load it on boot. What do you all think?

Shouldn't this package actually install the edid-generator script as well @flokli? That was my expectation.

Yeah, this should probably be split, have a package for the edid generator, and another component to create the edid binaries.

I'm not sure it that part should be a NixOS module, it feels more like a library function, that might also make sense to use independent of an individual NixOS instantiation.

Would you mind opening a PR?

I've been trying to get a custom EDID working for a couple of days, and have been documenting my progress with an eye towards upstreaming it in some form, but I'm stuck on two issues:

• [drm:edid_load [drm]] *ERROR* Requesting EDID firmware "edid/chipedp.bin" failed (err=-2) edrex/custom-edids#1
• DRM modes isn't updated when overriding EDID edrex/custom-edids#2

Do you mean a function in nixpkgs.lib to generate an EDID?

I haven't been successful yet (and there may be some hard reason why I won't be, in display capabilities), so it's hard to know if this is right, but it seems like a good progression for customizing your EDID is:

• Try loading a barebones one from edid-generator, if available, with the mode you want. (if not, gen with cvt | edid-generator). I haven't gotten this to work with the debug interface (sway/wlroots still shows the old edid, need to dig into that code to find out why).
• Once that's successful, start with a stock EDID from your display or a similarly-spec'd one (https://github.com/linuxhw/EDID) and copy the DTD you want from the above, into one of the four 18-byte regions. this could be automated with a simple script.

At the very least, I'd like to add a specific NixOS kernel option for adding a custom EDID file, since doing it using extraParams is a bit complicated (I haven't gotten it working yet, this was my attempt so far: edrex/nixos-config@c7c5f82)

i also want to package https://sourceforge.net/projects/wxedid/