Charcoal is an optimized Linux kernel for Steam Deck, Asus ROG Ally, and other AMD-powered handheld PCs, built on top of Valve's linux-neptune. It pushes the base further - built with LLVM/LTO/Polly, optimized for Zen 2, and patched with best-in-class schedulers like BORE and ADIOS. The result is a kernel tuned specifically for handheld gaming: better CPU responsiveness, improved I/O throughput, higher hardware limits, and bundled controller drivers - all without the bloat of debugging and unused features.
| Device | Status | Notes |
|---|---|---|
| Steam Deck (LCD) | ✅ Tested | Primary target |
| Steam Deck (OLED) | ✅ Tested | Primary target |
| Asus ROG Ally (RC71L) | ✅ Tested | Community-confirmed |
| Other AMD handhelds | ❓ Untested | Open an issue if you try it! |
- Optimize kernel with
-O3(from tkg) - Optimize for Zen 2 architecture (from Gentoo)
- Build with LLVM + LTO + Polly
- Built-in various always-needed modules so LTO can shine even more
- Add BORE - Burst-Oriented Response Enhancer CPU scheduler; prioritizes short CPU bursts for better frame pacing and input latency in games
- Add ADIOS - adaptive I/O scheduler tuned for responsiveness
- Add re-swappiness - fixes broken vm.swappiness behavior under MGLRU (without this patch, the kernel effectively ignores the swappiness value)
- Add zram-ir - tries multiple compression algorithms immediately on write so pages get the best ratio without waiting for background recompression
- Add kcompressd-unofficial - dedicated zram compression thread
- Add POC-Selector - O(1) idle CPU lookup replacing the default linear scan hot path
- Add Nap - neural network CPUIdle governor that predicts optimal idle states per-CPU
- Switch default DRM scheduling policy to round-robin
- Switch CPU idle scheduler
- Disable CPU mitigations (single-user device; gains measurable performance)
- Raise maximum CPU frequency from 3.5 GHz to 4.2 GHz
- Raise maximum PPT power limit from 30 W to 50 W
- Add WiFi patches from OpenWRT (improved stability)
- Add wait-on-multiple-futexes opcode for fsync (from tkg)
- Add some Clear Linux patches (from tkg)
- Add some Zen Linux patches
- Small fixes (from Gentoo)
- Fix DKMS with LLVM/Clang (from CachyOS)
- ryzen_smu - Ryzen SMU access for power monitoring
- xone - Xbox One wireless dongle driver
- xpad-noone - removes xpad support for controllers handled by xone/xpadneo, allowing those drivers to take over
- xpadneo - advanced Xbox controller driver
- Disable sound input validation
- Disable a lot of debugging overhead
- Disable various unneeded features (open a bug report if something you need is missing)
Add NTSYNC- Valve added it in 6.11.11-valve27Add Binder module (for Waydroid)- Arch Linux enabled it in 6.12.7Switch scheduling frequency to 1000 Hz- Arch Linux changed it in 6.13.1Update zstd- no longer needed for modern kernels
Download the latest release and run the following on your device:
cd ~/Downloads
sudo steamos-readonly disable
sudo pacman -U linux-charcoal-*-x86_64.pkg.tar.zst # Confirm when asked to remove linux-neptune-*
sudo steamos-readonly enable
rm linux-charcoal*Reboot and verify with:
uname -a # Should contain "charcoal" if installation was successfulYou can also verify in Gaming Mode under Settings → System, where the kernel version is shown.
Note: You may see messages like
==> ERROR: module not found: 'ata_generic'during install. These are harmless warnings, not real errors.
Important: SteamOS updates overwrite the root and boot partitions, which will remove the Charcoal kernel and break modules. After any SteamOS update, check
uname -aand reinstall ifcharcoalis no longer in the output.
To remove Charcoal and return to the stock Neptune kernel:
sudo steamos-readonly disable
_neptune=$(pacman -Qi $(pacman -Qq 'linux-charcoal*') | awk '/^Replaces/{print $3}')
sudo pacman -Rsn $(pacman -Qq 'linux-charcoal*')
sudo pacman -S "$_neptune"
sudo steamos-readonly enableThen reboot.
Requires Docker (provides a full Arch Linux build environment).
# Clone the repo first (you need it for the Dockerfile)
git clone https://github.com/V10lator/linux-charcoal
cd linux-charcoal
# Build the Docker image
docker build -t linux-charcoal .
# Start an interactive session and build inside
docker run --rm -it -v "$PWD:/project" linux-charcoal bash
# Inside the container:
cd /project && makepkg -sAlternatively, build with makepkg directly on any Arch-based system. Required dependencies: llvm, clang, lld, polly, bc, cpio, pahole, python, git, openssh - see PKGBUILD for the full list.
Bug reports and compatibility reports are welcome - open an issue. If you've tested Charcoal on a device not listed above, let us know so we can update the table!
Pull requests should target the master branch. For kernel config changes, please explain the reasoning and the impact.