[Success] Radeon RX 6800 XT - Big Sur

[vandroiy]

+1

"That'll be nice to get rid of extra stuff, but will probably need more laymens directions then that as I don't have any idea what to do with SSDT-BRG0 or GfxUtil. put some instructions on it and i'll test it over all the hacky FakePCIID stuff"

Well, gfxutil will show you correct path to GFX0. You have to insert it in DeviceProperties like on my screenshot. Just drag binary file on Terminal and press Return button.
SSDT-BRG0 is used to assign bridge name for your card. All Radeon cards starting from Vega works through extra bridge. You can see it in IOReg (PEG1->PEGP->pci-bridge->GFX0). In order to inject DeviceID to GFX0 you need to determine pci-bridge device in ACPI. If you did it correct your IOReg should look like this

Without this SSDT your deviceID for GFX0 will not be injected.
Also short description of this fix described in SSDT-BRG0 source code.

 

[Gigamaxx]

That'll be nice to get rid of extra stuff, but will probably need more laymens directions then that as I don't have any idea what to do with SSDT-BRG0 or GfxUtil. put some instructions on it and i'll test it over all the hacky FakePCIID stuff

The GFxUtil gives you the correct and complete path to the GPU. This is added to the Devices Properties as shown.

The SSDT may work out of box if your IOReg shows PEGP, PEG0 if not you will need to edit it (AMD Ryzen = IOPP, GPP17, etc…. ). You may also need to use ACPI patches or renames to get PEGP, etc.. for Intel systems.

 

[Gigamaxx]

Well, gfxutil will show you correct path to GFX0. You have to insert it in DeviceProperties like on my screenshot. Just drag binary file on Terminal and press Return button.
SSDT-BRG0 is used to assign bridge name for your card. All Radeon cards starting from Vega works through extra bridge. You can see it in IOReg (PEG1->PEGP->pci-bridge->GFX0). In order to inject DeviceID to GFX0 you need to determine pci-bridge device in ACPI. If you did it correct your IOReg should look like this
View attachment 524909

Without this SSDT your deviceID for GFX0 will not be injected.
Also short description of this fix described in SSDT-BRG0 source code.

Has anyone tested with Ryzen?

 

[vandroiy]

Has anyone tested with Ryzen?

I have no idea, but I see no reason why it would not work.

 

[byteminer]

Oh yeah, if anybody wants to give it a try, here's the pre-built WEG kext.
I built it from "master" this morning and figured it'd save some people a few steps by providing it here.

 

[Gigamaxx]

Oh yeah, if anybody wants to give it a try, here's the pre-built WEG kext.
I built it from "master" this morning and figured it'd save some people a few steps by providing it here.

That is the hardest part and requires Xcode.

 

[byteminer]

Which is why I provided the pre-built binary here.
Also, the easy way of doing this is to just fork the WEG repo and manually trigger the CI job, which builds this for you without any setup being required. You get 2000 build minutes for free on any GitHub account, so this is quite handy.

 

[vandroiy]

All nightly builds stored here.

 

[loiphin]

Well, gfxutil will show you correct path to GFX0. You have to insert it in DeviceProperties like on my screenshot. Just drag binary file on Terminal and press Return button.
SSDT-BRG0 is used to assign bridge name for your card. All Radeon cards starting from Vega works through extra bridge. You can see it in IOReg (PEG1->PEGP->pci-bridge->GFX0). In order to inject DeviceID to GFX0 you need to determine pci-bridge device in ACPI. If you did it correct your IOReg should look like this
View attachment 524909

Without this SSDT your deviceID for GFX0 will not be injected.
Also short description of this fix described in SSDT-BRG0 source code.

Thank you vandroiy I eventually got it working. Took some more research though. Over the years I have gotten pretty rusty as I have just been using CaseySJ's Z390 Designare OpenCore pack and not had to think much

By the way, where does the device-id of "BF730000" come from? Where did you figure that out from?

For those interested, I got a XFX Merc 319 6900 XT Limited Black card to work with Big Sur using the above method, on a Z390 Designare mobo.

I get a Metal score of 202000 on Geekbench 5.

 

[byteminer]

It's the 0x73BF device ID from the regular 6900XT. We compared and found that this ID is available and supported in the driver, while the one from the XTXH version (which has a slightly different device ID) is not.