Ok, re. "patchless" 4k (i.e., instead of a patch, getting 4k working directly with WhateverGreen [WEG] using DeviceProperties in the OpenCore config.plist).
A few different attempts:
Interestingly, this list included some of the settings that the 4k-Patch patched (e.g., Framebuffer Memory, DVMT allocation) and looked promising. I also noticed framebuffer-cursormem showed up here and was turning up in a few searches related to HD4600. That was a solid lead because when I tried to replicate the 4k patch in my WEG config.plist settings
earlier I experienced some glitchy/artifacty cursor stuff. I went back and added the two 4k patch values then added a third cursormem value (set at 00009000 because that's what it was in the list I linked to) but that caused a panic. I went back and tried adding the
entire WEG HD600 patch equivalent (nothing). Then, I played around with a few specific combinations of the settings to replicate the 4k-patch again (no success, occasional panics).
I don't really know what the cursormem value (or the other values) should be anyways so really I'm just danger-pasting stuff around and crossing my fingers.
Summary of initial findings:
I've posted this before, but as far as I can tell the original 4k patch does the following to AppleIntelFramebufferAzul.kext:
- Finds the PlatformID (0300220D), and the pipe and port count (0030303) but makes no changes to them.
- Finds and replaces the DVMT from 00000002 to 00000004 to set a 64MB DVMT allocation (which matches the changes we made in the bios)
- Finds and changes the Framebuffer memory size from 00003001 (32MB) to 00000003 (48MB).
- Alternatively, both of these changes can be accomplished in the DeviceProperties for WhateverGreen in the config.plist. However, that method doesn't enable 4k for me (stays 2k).
- It's still a solid approach, but I'm at a stage where I don't actually know how to interpret the more in-depth WEG Framebuffer stuff, or what combination of properties and settings in WEG would enable 4k.
Next steps:
- Moved from 14,3 -> 15,1 (which is a 27" 5k 2015 iMac).
- This should allow for Big Sur installation (and is stable for me right now - clarification: Catalina is stable with 15,1 I haven’t tried the beta)
- Nope, 4k doesn't work by default (too bad), patch still required but it's otherwise stable
TL;DR, I can't figure out a way to get 4k working via WhateverGreen, but I posted a bunch of info/trials here in case it inspires someone who actually knows what they're doing