Instructions on how to disable/tweak the Pixel Refresher on LG OLED CX

NB: This would have been posted in answer to this or this but unfortunately these posts are archived, so it's not possible to comment on them... And when I tried to create a topic in reddit's /r/OLED community, the moderators shadowremoved the post without providing any explanation. Way to create a welcoming community, guys...

PREAMBLE

Now, before people jump on "It's there for a reason - You should not disable the LG Pixel Refresh!" bandwagon, let me explain my reasons for doing so:

• I have been the happy owner of an LG OLED65CX for the past four years, but, over the last few months, it has started to develop the dreaded TV not turning on on first try issue ⁽¹⁾⁽²⁾ (which is absolutely maddening in terms of LG having completely let their customers down on an otherwise great product, through shoddy PSU hardware design - The Samsung LCD TV I had before that and which this LG OLED replaced, is now 17 years old but powering up and working fine for crying out loud!). Coincidentally, the power issue started to happen around the 2000 hours panel usage mark.

• Which means that the TV can no longer properly turn on from standby after it has been off for a while.

• Which means that the long form Pixel Refresher is unable to run altogether.

• Which means that, every time I shut down or (eventually manage to) power up the TV, I get the reminders about the Pixel Refresher, which I cannot do anything about!

• And of course, I have tried running the Pixel Refresher manually, but even a manual run still waits for complete standby before running it, which means it still has the same issue as trying to run through the scheduler, as the TV can simply no longer power itself up on first attempt.

So, yes, when you don't have any other choice, there do exist legitimate reasons why you may want to disable the Pixel Refresher.

And, yes, it is possible to accomplish just that (at least on OLED CX models, I obviously cannot vouch for any other model) provided that you have enabled root access.

DISCLAIMER

THE COMMANDS BELOW ARE FOR ADVANCED USERS ONLY AND ARE PROVIDED WITHOUT ANY WARRANTY OF IMPLIED FITNESS FOR A SPECIFIC PURPOSE. SHOULD YOU DO CHOOSE TO RUN ANY OF THESE COMMANDS, YOU ACCEPT THAT THERE EXISTS A RISK THAT THEY MAY RESULT IN HARDWARE DAMAGE AND/OR LOSS OF WARRANTY, AND AGREE THAT THE ENTIRE RESPONSIBILITY OF RUNNING SAID COMMANDS LIES ENTIRELY WITH YOU.

COMMANDS TO DISABLE/TWEAK THE LG PIXEL REFRESHER

• Log on to your OLED TV as root through ssh/telnet and issue the command:

luna-send -d -n 1 -f "luna://com.webos.service.oledepl/getPixelRefresherInfoList" '{ "subscribe": false }'

This should return something like:

{
    "jbInterval": 2000,
    "returnValue": true,
    "jbLastTime": 0,
    "offrsInterval": 4,
    "offrsCount": 427,
    "offrsLastTime": 2030,
    "subscribed": false,
    "jbCount": 0,
    "pnwashKeyLock": true
}

• If it doesn't return anything, STOP and don't proceed any further, as your model or firmware is using a different way of controlling the Pixel Refresher from what I am describing.

• In the above, jb is the prefix for the "long form" Pixel refresher, that is scheduled every 2000 hours (jbInterval) and offrs is the "short form" Pixel Refresher that runs every 4 panel usage hours or so. Obviously, the one that is of interest to us, since it's the one that produces the popups, is the jb one.

• At this stage, you have 2 ways to approach the issue. You can either increase the interval at which the long form Pixel Refresher is scheduled to run. For instance, you can set it to 4000 hours by issuing:

luna-send -d -n 1 -f "luna://com.webos.service.oledepl/setPixelRefresherInfoList" '{ "jbInterval": 4000,"subscribe": false }'

• Or you can tell the system that the long form Pixel Refresher has run, by issuing:

luna-send -d -n 1 -f "luna://com.webos.service.oledepl/setPixelRefresherInfoList" '{ "jbLastTime": 2000, "subscribe": false }'
luna-send -d -n 1 -f "luna://com.webos.service.oledepl/setPixelRefresherInfoList" '{ "jbCount": 1, "subscribe": false }'

For good measure, I ran both on my model, and I was finally free from annoying Pixel Refresher reminder popups. Of course, this doesn't do anything to solve the major issue that appears to affect many CX models, including mine, with powering on the panel, but if, for whatever reason, you are looking at a means to tweak or disable the LG Pixel Refresher (on CX and similar models) now you know how to do it.

Oh and in case you want to explore what other commands the com.webos.service.oledepl provides, you can also issue:

ls-monitor -i com.webos.service.oledepl

It should also be noted that com.webos.service.oledepl is actually mapped to the /usr/sbin/eplmanager executable, which you can also run manually with the -d (Debug) option if you are feeling adventurous, but I REALLY wouldn't advise to do so, as you can probably break your TV beyond repair if you try things at random there, whereas the luna-send are assumed to have some form of validation...

Reboot to UEFI firmware settings from UEFI Shell

reset -c -fwui

There, you have it.

Adding EDK2 as a submodule without cloning it

Yeah, I have my reasons for this (mostly I commit on Windows, run the builds through GitHub Actions but compile from a non version-controlled Linux, and I don't want to suffer the wastage of yet another lengthy and cumbersome clone of EDK2).

This is mostly taken from https://stackoverflow.com/a/37378302/1069307:

mkdir edk2
git update-index --add --cacheinfo 160000 b158dad150bf02879668f72ce306445250838201 edk2
cat <<EOF >>.gitmodules
[submodule "edk2"]
	path = edk2
	url = https://github.com/tianocore/edk2.git
EOF

Of course, you should replace the commit hash with whatever current or stable EDK2 commit hash you want to point to.

And with this, you'll have added EDK2 as a submodule of your project without going through a cumbersome clone.

Downloading signtool.exe from Microsoft

In their typical fashion, unless you know what you're doing, Microsoft made it incredibly difficult to get your hands on a simple basic executable, that they should by all means provide as an easily accessible download, since it's one of the basic brick to try and safeguard a Windows platform.

Well, we know what we're doing, which is to use a very handy technique that we picked up from actual malware, so, from PowerShell:

curl.exe -L -A "Microsoft-Symbol-Server/10.0.0.0" https://msdl.microsoft.com/download/symbols/signtool.exe/910D667173000/signtool.exe -o signtool.exe

There. Now you have signtool and you can get on with your life without having to download 4 GB of extra garbage.