librocdxg RDNA2 Patch

An experimental fork of ROCm/librocdxg.

This repository adapts librocdxg for use with selected RDNA2 systems under WSL2 and includes entries for additional RDNA2 PCI IDs.

This work was inspired by a fork of an earlier librocdxg commit: joshEng1/librocdxg-gfx1032fix.

It is not a standalone runtime. It builds and installs librocdxg with these extra compatibility changes while relying on the normal ROCm stack, Windows driver, and WSL environment.

Why this fork exists

RDNA2 is not included in upstream librocdxg's published WSL compatibility matrix. Some RDNA2 configurations can work with additional device information, gfx-version override handling, and queue-related changes.

This repository is mainly intended for experimentation with the listed devices and for the Ollama setup described below.

RDNA2 coverage

The fork currently contains entries for:

Family	Native ISA	PCI IDs	GPU models associated with these IDs
Navi 21	gfx1030	73BF, 73AF, 73A5	RX 6800, RX 6800 XT, RX 6900 XT, RX 6950 XT
Navi 22	gfx1031	73DF	RX 6700, RX 6700 XT, RX 6750 XT, RX 6800M, RX 6850M XT
Navi 23	gfx1032	73E3, 73EF, 73FF	Radeon PRO W6600, RX 6600, RX 6600 XT, RX 6600M, RX 6650 XT, RX 6700S, RX 6800S
Navi 24	gfx1034	743F, 7424	RX 6300, RX 6400, RX 6500 XT, RX 6500M

Several products share PCI IDs, so an entry does not guarantee identical behavior across every card using that ID. The table describes what the fork recognizes; it is not an official support list.

Install

First install ROCm and its normal WSL prerequisites using AMD's ROCm installation guide. You also need WSL2, a compatible AMD Windows driver, CMake, GCC, and the Windows SDK.

Clone and build this fork inside WSL:

git clone https://github.com/the-zucc/librocdxg-rdna2.git
cd librocdxg-rdna2

# Adjust the SDK version if necessary.
export win_sdk='/mnt/c/Program Files (x86)/Windows Kits/10/Include/10.0.26100.0'

mkdir -p build
cd build
cmake .. -DWIN_SDK="${win_sdk}/shared"
make -j"$(nproc)"
sudo make install

The fork installs librocdxg into the existing ROCm prefix, replacing the installed librocdxg library while continuing to use the rest of the upstream ROCm stack.

Enable and verify RDNA2

Set the environment used for the tested RDNA2 setup. The gfx override makes the device appear as gfx1030 to the ROCm runtime:

export HSA_ENABLE_DXG_DETECTION=1
export HSA_OVERRIDE_GFX_VERSION=10.3.0
export HSA_ENABLE_SDMA=0
export HSA_ENABLE_PEER_SDMA=0
export LIBROCDXG_ALLOC_USER_QUEUE_FROM_UMD=1

rocminfo

A working adapter should appear as a GPU agent. For example, the Navi 22 test system used for this fork reports:

Name:                    gfx1030
Marketing Name:          AMD Radeon RX 6700 XT
Chip ID:                 29663(0x73df)
Compute Unit:            40

These settings are included because they were used with the working setup. Other combinations may also work, but have not been validated here.

Ollama

Create an Ollama service override with sudo systemctl edit ollama:

[Service]
Environment="HSA_ENABLE_DXG_DETECTION=1"
Environment="HSA_OVERRIDE_GFX_VERSION=10.3.0"
Environment="HSA_ENABLE_SDMA=0"
Environment="HSA_ENABLE_PEER_SDMA=0"
Environment="LIBROCDXG_ALLOC_USER_QUEUE_FROM_UMD=1"
Environment="OLLAMA_FLASH_ATTENTION=1"

Apply it with:

sudo systemctl daemon-reload
sudo systemctl restart ollama

Project scope

The goal is to keep this RDNA2 experiment usable as upstream librocdxg evolves. For general librocdxg usage, releases, and official compatibility information, see the upstream repository for those details.

Behavior can vary with the exact GPU, Windows driver, ROCm release, and code objects shipped by an application. The RX 6700 XT configuration shown above was verified with rocminfo; other entries have not all been tested on hardware in this repository.