Re: [PATCH v2 0/5] fbdev: tdfxfb: Make "unbooted" cards work

Helge Deller <[email protected]> Fri, 31 Jul 2026 14:38:06 +0200
Newsgroups org.kernel.vger.linux-fbdev,org.freedesktop.lists.dri-devel,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
On 7/31/26 14:19, Daniel Palmer wrote:
> Currently voodoo cards that weren't booted by the video BIOS aren't
> usable because the hardware is never brought up.
>=20
> This means if you happen to have a proper - non-x86 - computer,
> another card is the primary or you have a new BIOS that cannot
> run the video BIOS tdfxfb would probe but you will be staring at
> "no signal detected".
>=20
> This series implements manually booting cards using the
> values from the video BIOS' own table. Currently this only works
> for the voodoo 3.
>=20
> Debugging was partially assisted by Claude Fable 5. I could not
> work out why this would not work for months so I told it to
> create a voodoo 3 emulation for QEMU to compare the BIOS against
> my code. That made it obvious my init sequence matched the BIOS
> but the VGA core wasn't running.
>=20
> This has been tested on a real voodoo 3 in an x86-64 board and
> an Amiga 4000 with a mediator PCI bridge.
>=20
> I have some patches to add an interface for doing 3D rendering
> that are not included in this series and 3D rendering is also
> working so as far as I can tell everything is good.
>=20
> v2:
>    - Fix up some poor 3am English mistakes in the cover letter.
>    - Limit this to the voodoo 3. The BIOS layout is different
>      for the 4/5 apparently.
>    - Fixed the valid sashiko complaints - mainly clearing the
>      framebuffer memory before fbcon might have bound, retaining
>      the current behaviour if we can't get the video BIOS to get
>      the config parameters.
>    - Tweaked the wording of some of the commit messages.
>=20
> Daniel Palmer (5):
>    fbdev: tdfxfb: Add helper to read config table from BIOS
>    fbdev: tdfxfb: Attempt to detect if the card wasn't booted
>    fbdev: tdfxfb: Manually boot unbooted cards
>    fbdev: tdfxfb: Wake the VGA core before programming the CRTC
>    fbdev: tdfxfb: Program the initial video mode
>=20
>   drivers/video/fbdev/tdfxfb.c | 155 +++++++++++++++++++++++++++++++++++
>   1 file changed, 155 insertions(+)
New series applied to fbdev.

Thanks!
Helge