Sorry for not being clear. Yes, I mean the Tianocore firmware.
So I've added Jeremy to my reply as he's the maintainer of this
firmware but as it's EDK2 and ACPI, as opposed to device tree, I'm not
sure it's intended to work.
As the driver would need ACPI support and the firmware would need the
appropriate ACPI tables to describe the hardware. I'm not sure what
the plans there are for support for the GPU on that firmware is, the
timeline or if there is any plans there.
Peter