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[BUG] Black screen 3 minutes after booting, CoffeeLake UHD 630

@RehabMan correct me if I’m wrong, we can get UHD 630 to work on 10.13.6 using FakeIDs of Kabylake, right?
 
My laptop is dell 7380, with CPU i5-7200U, HD620, platform-id is 59160000.
I was having exactly the same issue, however, I solved the issue after many tries.

Maybe UHD630 is different from HD620, but I wrote here to provide you some information for reference. (I tried only on 10.14.1)


try 1:
Operation:
official whatevergreen (1.2.4)+ applebacklightfixup.kext + config.plist & PNLF.aml found from https://github.com/RehabMan/OS-X-Clover-Laptop-Config

Observations:
- Internal screen is black for 3 minutes, afterwards, the screen and brightness control works good, even after sleep and wakeup.
- Meanwhile, external screen works great all the time, right after boot.


try 2:
I googled and found this thread, so i changed to:
headkaze's whatevergreen (1.2.4b1, #191) + PNLF-debug.aml (I added the platform id 0x1659 to this aml in the coffee lake platform id judgement area to make the new debug code work on my HD620) + SSDT-RMDT.aml + igfxcflbklt=wrap

Observations:
- Internal screen is on right after boot (sounds good), but internal screen is black after sleep (it's bad)
- External is still fine.

I also tried many ways, such as adding config.plist/Devices/framebuffer-* options, or injecting EDID with 0x9c7c, or use modifed whatevergreen with option igfxcfbklt=freq, etc... There was no luck.


try 3 (finally...) :
I restored everything with the operations in try 1, and this time I also add SSDT-RMCF.aml. and set LMAX to 0x0D88.
Now the internal and external screen works just great!


Why the number is 0x0D88?
Because I followed a thread by rehabman (I can't find the URL right now) to find my PWMAX:
- install hex fiend, run command:
open -a "Hex Fiend" /System/Library/Extensions/AppleIntelKBLGraphicsFramebuffer.kext/Contents/MacOS/AppleIntelKBLGraphicsFramebuffer
- search for your platform id HEX, e.g. 00001659, and use the number around offset 32 (maybe)
- my HEX in 10.14.1 is 00001659 4C890DAA 9408004D 89CEB201 8815A794 0800880D A2940800 880D9D94 0800880D 98940800 C7058F94 08000000 20028905 ...., so I just used 0x0D88

BTW, in 10.14.0, the hex code for 00001659 is different in Framebuffer...


In conclusion , I guess some laptops just show the lowest brightness level (and the lowest brightness level is just black screen, caused by kext or aml) right after the boot. And after 3 minutes, something happend (maybe a sleep/wakeup, or sth in the system), and the brightness level just rose from the lowest level to a higher one, so the screen is back.
 
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My laptop is dell 7380, with CPU i5-7200U, HD620, platform-id is 59160000.
I was having exactly the same issue, however, I solved the issue after many tries.

Maybe UHD630 is different from HD620, but I wrote here to provide you some information for reference. (I tried only on 10.14.1)


try 1:
Operation:
official whatevergreen (1.2.4)+ applebacklightfixup.kext + config.plist & PNLF.aml found from https://github.com/RehabMan/OS-X-Clover-Laptop-Config

Observations:
- Internal screen is black for 3 minutes, afterwards, the screen and brightness control works good, even after sleep and wakeup.
- Meanwhile, external screen works great all the time, right after boot.


try 2:
I googled and found this thread, so i changed to:
headkaze's whatevergreen (1.2.4b1, #191) + PNLF-debug.aml (I added the platform id 0x1659 to this aml in the coffee lake platform id judgement area to make the new debug code work on my HD620) + SSDT-RMDT.aml + igfxcflbklt=wrap

Observations:
- Internal screen is on right after boot (sounds good), but internal screen is black after sleep (it's bad)
- External is still fine.

I also tried many ways, such as adding config.plist/Devices/framebuffer-* options, or injecting EDID with 0x9c7c, or use modifed whatevergreen with option igfxcfbklt=freq, etc... There was no luck.


try 3 (finally...) :
I restored everything with the operations in try 1, and this time I also add SSDT-RMCF.aml. and set LMAX to 0x0D88.
Now the internal and external screen works just great!


Why the number is 0x0D88?
Because I followed a thread by rehabman (I can't find the URL right now) to find my PWMAX:
- install hex fiend, run command:
open -a "Hex Fiend" /System/Library/Extensions/AppleIntelKBLGraphicsFramebuffer.kext/Contents/MacOS/AppleIntelKBLGraphicsFramebuffer
- search for your platform id HEX, e.g. 00001659, and use the number around offset 32 (maybe)
- my HEX in 10.14.1 is 00001659 4C890DAA 9408004D 89CEB201 8815A794 0800880D A2940800 880D9D94 0800880D 98940800 C7058F94 08000000 20028905 ...., so I just used 0x0D88

BTW, in 10.14.0, the hex code for 00001659 is different in Framebuffer...


In conclusion , I guess some laptops just show the lowest brightness level (and the lowest brightness level is just black screen, caused by kext or aml) right after the boot. And after 3 minutes, something happend (maybe a sleep/wakeup, or sth in the system), and the brightness level just rose from the lowest level to a higher one, so the screen is back.



Gave this a shot on a Razer Blade 15 with the UHD630, all it did was break brightness control and still had the black screen on boot up. Was worth a shot to try.
 
Gave this a shot on a Razer Blade 15 with the UHD630, all it did was break brightness control and still had the black screen on boot up. Was worth a shot to try.

Attach PR files as per FAQ.
 
I'm still working to get this working. On my Dell G3, i7-8750H version, the first post-install boot was quite ok, nothing happened to screen (but I also tested and had no brightness control), also in this first boot I had full Graphics support fom Coffe Lake (Thanks 10.14 native support).

I installed some kexts to fix audio & battery management, and then I first saw the black screen problem... I realized that, if you still didn't installed AppleBacklightFixup.kext, the hole screen brightness control was made by the platform-id (even if Intel Injection was off), so I googled around and found some options to test brightness (again, I didn't had installed the Backlight Fixup).

My tries: - 3E9BXXXX - it gave me black screen (3min later, it came back, but no brightness control through keyboard), 7MB of video-memory + sleep&wake not working
- 12345678 - Black screen was gone, straight boot up with full brightness, but with no control and 7MB of memory.
- 00000000 - The default support to CoffeLake devices, again it booted without brightness or control and 3min later screen got back to normal, with full graphics acceleration for UHD 630 (1536MB).

And then I tried to fix with AppleBacklightFixup + SSDT provided into it's guide post, and no changes were made to my system, still no brightness. I'll still patch my own SSDT's an DSDT's, and then I'll tell you guys any progress (if I have any).
 
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Looks like we're in this for the long hall for a fix. More laptops are going to end up with the UHD 630/620 graphics so eventually there will be a fix. But development looks to have come to a standstill for the time being until someone who builds WEG gets their hands on a machine with the specific hardware and bug.
 
So diving back into this, I have come across an issue that is related to the 3 minute black screen. I have been having an issue with my hackintosh and it randomly freezing up and having to be rebooted every so often while using the laptop. It was never app specific, or task specific. I did a bunch of troubleshooting and couldn't figure it out. Then came across a few people that didn't have this issue on the same laptop with the same installation, the only difference is they never implemented Native Brightness and don't have the 3 minute black screen bug. So I decided to roll back my native brightness set up and just deal without having brightness controls and the random freezing issue is gone.
So it seems to be possible that the same Framebuffer bug that we have going on that causes the 3 minute black screen on start up is also causing random system crashes after so many hours of running on the laptop with no reboots. Which I guess would mean that this bug is a bit bigger than we thought?

Has anyone else had this kind of issue also?
 
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