Strange problem with 2015 Macbook Pro, white screen, Brave freezes

Hardware Support
1

I have a 2015 Macbook Pro with the following specs:

Hardware
Hardware Model: Apple Inc. MacBookPro11,5
Processor: Intel® Core™ i7-4870HQ × 8
Memory: 16.0 GİB
Disk Capacity: 500.3 GB
Graphics: Intel® Iris® Pro Graphics P5200 (HSW GT3) + AMD Radeon R9 M370X

Software
Firmware Version: 476.0.0.0.0
OS: Zorin OS 18 Core
Windowing System: Wayland
Kernel Version: Linux 6.14.0-37-generic

I have been trying to install Linux on it for a few weeks, but it doesn't cooperate. I only learned about the existence of ZorinOS today, so previously I tried the two distros that I had some experience with, Mint and Ubuntu. In both I had a graphics glitch for which the background was white, and many apps were also white and thus useless.

Eventually I learned a workaround for Ubuntu, consisting of editing the GRUB with "intel_iommu=igfx_off" or something like that. But that means that the OS will only use the CPU integrated graphics, not the Radeon, which may not be a great GPU, but still probably much better than the CPU one.

Today a friend sent me a link to ZorinOS, and I wanted to give it a try because it sounds like the Linux distro that is finally making a lot of people switch or at least consider Linux as a serious alternative to Windows. It also seems very well put together, with a good looking GUI (not crazy about the icons, though), but if it works well on this laptop, I would consider installing it in my PC along with Windows 11, which for the time being, I can't just ditch, as much as I would love to.

So I downloaded the Core edition, installed it in the MBP, and I was having the same white screen problems I was having with Mint and Ubuntu. But the weirdest thing is that after the first reboot after install, it was fine. Everything looked as it should.

But then I tried to launch Brave, which as you all know comes preinstalled, and I got this prompt:

IMG_2326
IMG_23261920×1080 62.2 KB

Seemed to me like the equivalent of Keychain in macOS, so I created a password and clicked continue. Brave opened, and froze immediately, but not just it, the whole machine. The mouse pointer was impossible to move, and it was doing heavy processing because the little fans started ramping up, and going to the max and staying there. I left it like that for about 12 minutes without any changes.

So I pressed the power key for several seconds to force a power off. Then I turned on again, and this time, all I saw was a white screen, although I could move the mouse pointer to the top right to access the module that has the power and restart, so I did a restart. Still the white screen.

Then it occurred to do a PRAM reset. Funny enough, after that, it booted up perfectly, showing me the login screen, and after entering the password, it booted to a perfect desktop with no white glitches. I played around with it, installed Firefox from the software center to avoid Brave, and installed a few more things. Then I rebooted, and it was back to the white screen.

I tried another reboot, same thing. I powered off, waited a minute and booted up, still all white. Did another PRAM reset, but this time it came back all white again.

All of this seems to me like Linux has a problem understanding the weird graphics system in this machine, which macOS was built to deal with seamlessly depending on whether the machine was plugged in or just on battery, but Linux doesn't seem to have the drivers or kernel or whatever is needed. Which surprises me, because if it wasn't for Linux, this machine would be worthless. Apple abandoned the model years ago, and Windows 11 cannot be installed because I don't think this laptop has TPM 2.0. Of course both can be tricked to install the latest version, but I'd rather run a Linux that supports the machine natively. It would be great if the Linux developers, especially for this distro, included support for it from the start, because they are very common machines that many people have and are sitting in a closet not being used.

It also seems to me that when it works, it's using the CPU's GPU, not the Radeon.

Has anyone else here run into these problems?

Then the next reboot, everything went white.

2

Since this model Mac works by keeping the intel GPU always on, and it transfers the Radeon processing through it using Proprietary Apple Firmware, I do not think any Linux Distro can provide the Prime Offloading you want. It's... how the machine was made - For Apple.

3

This kernel parameter turns off Intel graphics, not Radeon.

4

This parameter does not actually disable either. What it prevents is IOMMU passthrough, so that the Radeon card cannot passthrough the Intel GPU, which is mentioned above in post #2.
The way Apple set this up, the Intel GPU is always active and allways in control of display. When using the Radeon card, it does a transfer to the Intel GPU, which allows it to take the majority of the workload off the Intel GPU, but both are running.
It is weird. And why the Apple Firmware is needed in order to operate it.

That said, @VivaLaLinux might have some luck with:
intel_iommu=on intel_iommu=igfx_off as a grub parameter, as this may allow some passthrough, even if not the full Apple experience.

1 Like
5

The weird thing is that I read some forum posts from different people saying that they had actually enabled the Radeon and was working fine.

6

It can be enabled - just not to the full extent it can on a Mac. But yes, it can be. I would need to look up the full steps how to...
But if your goal is the Complete and full processing that you would get if using a Mac OS, that cannot be achieved.

If partial is "working fine" - I do not disagree that it is the way to go...

7

You're correct, I think I misremembered which parameter. It is the one that disables the Radeon actually, and only leaves the integrated GPU. I think it ends in radeonmode=0 or similar.

That said, while with that parameter in the GRUB ZorinOS loads fine and without any white backgrounds or glitches, I do get some mouse pointer glitches that I wasn't getting on either Mint or Ubuntu after using the same parameter in the GRUB.

8

Gotcha. Well, in the end, this is a machine I'm giving to a friend that cannot afford anything new, so I'll leave it up to him to figure it out.

But thanks for your replies!

1 Like
9

You could try if it is better when you switch to XOrg if you are on Wayland. Logout and at login click on your username then a cog wheal appears at the bottom right corner. There select "Zorin Desktop on Xorg".

Edit: I just notice that you use automatic login. Then the cog wheel doesn't exist and you would need to edit /etc/gdm3/custom.conf to enable XOrg or enable login with password (or you create another user account with password login then you'll get the cog wheel to choose XOrg or Wayland).

2 Likes