Note

An LLM was used to aid in development of this code.

Bug reports (please attach listdev output, syslog, and/or screenshots) and PRs welcome! See "Logging Bugs / How to Help" section below.

AST2400 - Haiku GraphicsDriver

Haiku graphics driver for the ASPEED AST2400 / AST2500 / AST2600 family of integrated BMC GPUs. These chips are found on most Supermicro, Dell, HPE, Asus server-line, and other enterprise server motherboards; the BMC's onboard VGA is typically the board's default display output even when no discrete GPU is installed.

Driver name ast, PCI vendor 0x1a03, device 0x2000. Generations are distinguished at runtime via the PCI revision register, matching Linux's ast_detect_chip() logic.

Note

This is not an upstream Haiku driver. It is GPL v2-licensed (because it ports register sequences from Linux's drivers/gpu/drm/ast/) and distributed as a standalone .hpkg for users with affected hardware. There is no plan to upstream these changes — Haiku does not accept GPL drivers into its MIT tree.

Release history: see CHANGELOG.md.

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Project Status

This driver is early-stage but usable. Each phase below has to clear hardware verification before the next starts.

Phase	Goal	Status
1	Probe + bind PCI device, map BARs, no display output	✅ verified on Supermicro X11SSH-LN4F
2	Accelerant skeleton — clones shared area, exposes mode list	✅ accelerant loads, app_server picks our driver
3	Actual CRTC + PLL + encoder programming — drive a real mode	✅ clean 1024×768@60Hz @ 32 bpp
4	Multi-mode support + EDID readback	✅ 4.0 multi-mode list · 4.1 EDID via DDC · 4.2 1920×1080
—	Defensive BAR-assignment validation (Haiku #3)	✅ 0.1.3
5	AST2500 / AST2600 silicon-init deltas, polish	⬜ not started

As of 0.1.3 the driver is a fully usable Haiku graphics driver for the AST2400 / AST2500 / AST2600 family. It supports 640×480 through 1920×1080 @ 60 Hz @ 32 bpp, dynamic mode switching from Screen preferences, EDID readback from the connected monitor, and defensive PCI-BAR-assignment validation. Remaining work (next phases) covers EDID-driven mode filtering, more 16:9 / widescreen modes, AST2500 / AST2600 silicon-init quirks, hardware cursor, and 2D acceleration.

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Tested Hardware

Brand	Board	Chip	PCI ID (rev)	Status
Supermicro	X11SSH-LN4F (Xeon E3-1230v5)	AST2400	1a03:2000 (rev 0x30)	✅ 0.1.3 — 1920×1080@60 verified · dynamic mode switching across 6 modes · EDID readback confirms HP V244h

Screenshot

Haiku Screen preferences reports the active driver as ASPEED Graphics (AST2400) at 1024 × 768, 32 bits/pixel, 60 Hz — driven through the BMC's onboard VGA output on a Supermicro X11SSH-LN4F.

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Installation

Grab aspeed_gfx_unofficial-<version>-x86_64.hpkg from the releases page, drop it in ~/config/packages/, and reboot:

cp aspeed_gfx_unofficial-*.hpkg ~/config/packages/
shutdown -r

To revert, remove the .hpkg and reboot:

rm ~/config/packages/aspeed_gfx_unofficial-*.hpkg
shutdown -r

If the driver panics at boot, boot to safe mode and delete the .hpkg from ~/config/packages/ before the next normal boot.

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Documentation

• CHANGELOG.md — per-version summary in Keep-a-Changelog format
• docs/technical-documentation.md — full technical write-up with register-level explanations, SVG diagrams, and the bring-up failure post-mortems
• docs/STYLE_GUIDE.md — coding style for the project
• docs/diagrams/ — SVG diagrams referenced from the technical doc (driver architecture, BAR layout, mode-set sequence, DDC I²C state machine, CR_A8 byte-order toggle)
• docs/screenshots/ — visual verification of each phase

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Building from source

Building from source is not required — install the .hpkg above. If you want to cut your own build (or contribute a fix):

1. Clone this repo.
2. Have a Haiku x86_64 source tree with cross-tools configured at $HOME/haiku-build/haiku (or pass a path as the first argument).
3. Run:

   scripts/build.sh
   scripts/package.sh 0.0.X

4. Output: dist/aspeed_gfx_unofficial-0.0.X-x86_64.hpkg.

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Logging Bugs / How to Help

Open an issue with as much detail as possible. From Haiku, attach:

• syslog (/var/log/syslog) — especially lines beginning with ast:
• listdev output (the PCI ID + revision tell us the exact chip)
• The motherboard make and model
• A photo of the screen if you hit a KDL or visual corruption

If you can also boot Linux on the same hardware, the output of lspci -nn | grep -i aspeed confirms the PCI ID and revision.

PRs are welcome. On your PR, indicate which board + BMC chip you tested on, and include the PCI ID + revision.

Please adhere to the docs/STYLE_GUIDE.md for coding conventions before opening a PR. There is a PR checklist that outlines a few key things to check.

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Why GPL v2 (not MIT)

Most Haiku drivers — including the bundled ones — are MIT. This driver is GPL v2 only because it ports register sequences from Linux's drivers/gpu/drm/ast/, which is GPL v2 only (no "or later" clause). The combined derivative work must therefore also be GPL v2.

This means:

• The driver cannot be upstreamed into Haiku in its current form.
• The tradeoff is accepted as the price of being able to lean on the Linux driver as the authoritative reference — ASPEED hardware is too sparsely documented publicly to drive blind.

See docs/STYLE_GUIDE.md §16 for the full licensing rationale.

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Source Material

The Linux drivers/gpu/drm/ast/ driver is the primary porting source for register sequences and silicon-revision handling.

xf86-video-ast (the older X11 driver) is a secondary reference, MIT-licensed.

When this driver substantially ports a function from Linux, the upstream copyright lines are preserved per docs/STYLE_GUIDE.md §16.2.

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License

GNU GPL v2 only. See individual source files for copyright lines.