# mesa-panvk-bifrost

Patched Mesa `libvulkan_panfrost.so` exposing Bifrost-gen Mali GPUs
(Mali-G31/G52/G72/G76, PAN_ARCH 6/7) to Chromium-family browsers'
Vulkan compositor.

Result of the **panvk-bifrost** campaign ([`~/src/panvk-bifrost/`](../../../panvk-bifrost/)),
iter9 close 2026-05-20 (technical milestone — operator-confirmed Brave
window) followed by this package as the actual delivery.

## What it solves

Stock Chromium / Brave on Bifrost SBCs (PineTab2, etc.) currently dies
at GL bindings init:

```
ERROR: ui/gl/gl_context_egl.cc:120  GLES3 is unsupported and ES version fallback is disabled
ERROR: ui/gl/init/gl_factory.cc:111  Requested GL implementation not found
ERROR: components/viz/service/main/viz_main_impl.cc:189  Exiting GPU process due to errors during initialization
```

This package makes Brave's **Vulkan compositor path** work on Bifrost,
side-stepping the failing GL stack. Browser chrome and standard page
rendering work.

## Known limitations (not addressed)

- **WebGL / WebGL2** in-page: blocked. ANGLE needs `VK_EXT_transform_feedback`
  to expose GLES3 contexts; PanVk-Bifrost doesn't currently support that.
  Sites using WebGL will degrade or refuse.
- **VAAPI hardware video decode**: unrelated to this package — see the
  `libva-v4l2-request-fourier` package for that path.

## Install

```sh
# Ensure [marfrit] is in /etc/pacman.conf, then:
sudo pacman -Sy mesa-panvk-bifrost
```

## Use

```sh
brave-vulkan                                    # launches Brave with Vulkan
brave-vulkan https://www.example.com
brave-vulkan --your-flags-here                  # extra args passed through
```

The launcher sets:

- `VK_ICD_FILENAMES=/usr/lib/panvk-bifrost/icd.json` (the patched driver)
- `PAN_I_WANT_A_BROKEN_VULKAN_DRIVER=1` (Mesa upstream gate)
- `MESA_VK_VERSION_OVERRIDE=1.2` (apiVersion bump for ANGLE)
- Brave flags: `--use-gl=disabled --enable-features=Vulkan --use-vulkan=native --ozone-platform=x11 --no-sandbox --disable-gpu-sandbox --ignore-gpu-blocklist`

## What's in the package

- `/usr/lib/panvk-bifrost/libvulkan_panfrost.so` — patched Mesa Vulkan driver (Mesa 26.0.6 + 2 sed-applied patches)
- `/usr/lib/panvk-bifrost/icd.json` — Vulkan ICD JSON pointing at the patched .so (NOT auto-loaded; only via `VK_ICD_FILENAMES`)
- `/usr/bin/brave-vulkan` — launcher script

System Mesa is untouched. The stock `/usr/lib/libvulkan_panfrost.so` and
`/usr/share/vulkan/icd.d/panfrost_icd.json` continue to work for any
other Vulkan app.

## Co-existence

Both stock Mesa and this package can be installed. Stock Vulkan apps
(`vulkaninfo`, `vkcube`, etc.) use the stock driver by default. Only
apps started via `brave-vulkan` (or with `VK_ICD_FILENAMES` manually
set to our path) use the patched driver.

## Campaign close criterion

Per [`feedback_package_done_means_installable`](file:///home/mfritsche/.claude/projects/-home-mfritsche-src/memory/feedback_package_done_means_installable.md)
three-point check:

1. PR merged to `marfrit-packages`
2. CI green AND `packages.reauktion.de/arch/aarch64/mesa-panvk-bifrost-*.pkg.tar.zst` exists
3. `pacman -Ss mesa-panvk-bifrost` on a fresh consumer host (e.g. ohm
   after `pacman -Syu` from clean state) returns the package + brave-vulkan launches

When all three pass, panvk-bifrost iter9 closes.