What does MNT RKX7 (FPGA) use for a GPU?

So since I found out about MNT I’ve been very interested in the RKX7 project to make a working MNT laptop with an onboard FPGA:

https://mntre.com/media/reform_md/2022-09-29-rkx7-showcase.html

[shop link removed because of Discourse rules]

It doesn’t seem to specifically say this, but I got the sense (?) the RKX7 replaces the CPU module, and if I understand the MNT store correctly (?) the CPU module typically contains the GPU.

So I am curious, when running an MNT in the RKX7 configuration, what does it use for, or in place of, the GPU?

The shop page (“Ships in September 2023”) says the RKX7 “requires an RGB to eDP Adapter” to connect it to the internal display; in the update post from last year, MNT says that they’ve successfully built and run linux on a RISCV core, but doesn’t mention gpu (unless it’s part of “the LiteX SoC”— I know LiteX is a macro package for making riscv chips/socs quickly but that’s all I know).

I ask this because I am learning FPGA programming (at a very beginner level— I’ve done a small ICE40 project and have an Analogue Pocket coming soon in the mail) and I am interested in GPU or GPU-approximation tech in FPGAs. It seems like recently there are many open-hardware laptop/raspi-scale computer projects that have wound up with an almost fully open source stack EXCEPT the GPU (RISCV cpu, Open Hardware BIOS, Linux OS … proprietary GPU). It seems like there is a hole in the open-hardware ecosystem and I am curious what can fill it.

How does this work on the MNT?

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For context, the shop link cut out above: MNT RKX7 FPGA Processor Module - MNT Research Shop

Lukas talks about the GPU of the RKX7 in this recent keynote:

The RKX7 can drive the display but only 2D and only very slowly. Even terminal scrolling seems to be not smooth. In that video Lukas also laments that there is no libre GPU and the best we have are reverse-engineered non-free GPUs like the etnaviv driver for vivante gpu in the imx8mq. In the video Lukas mentions that there are some attempts for a free GPU implementation for FPGAs but only by some researchers and nothing widely used out there.

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