Re: [9fans] Has anyone run 9front on Libreboot (libgfxinit) without a VGA BIOS?

[ron minnich <rminnich@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 2502 bytes --]

There is i915 support in coreboot, not sure how much of that libreboot got
when it forked.

ca 2002, David Hendriks and I got graphics working, which later led to this
fun video: https://youtu.be/DmK_SQI56fQ?si=cNhl1v-5ZR4f5VYM

I put the i915 support in coreboot while I was working on chromebooks. We
showed this can be fast: https://youtu.be/4qLDjHThCyE?si=KFAkWdZjG1ggsRlp
as compared to intel's incredibly slow graphics layer in UEFI. (that video
ignores Intel's VGA BIOS entirely; it is coreboot vs. linux graphics
startup).

Later, others greatly improved the coreboot graphics support. I have no
idea what libreboot has done, or if they've kept up. Libreboot did have a
desire not to use vendor graphics BIOS in startup (i.e. no blobs), and that
might be an issue.

as for coreboot, x220, and Plan 9: do you see anything at all on the screen
before linux starts?

I developed coreboot graphics support by watching all the ins/outs/memory
read/memory write that linux did.This was possible because,  at the time
(2012) Jesse Barnes, then at Intel, had worked hard to make LInux graphics
work without needing the Intel video BIOS: chromebooks in normal mode let
Linux do ALL graphics startup. IIUC, Intel did not keep that
BIOS-independence going, and I believe a BIOS-free graphics setup on Intel
display hardware no longer works.

If you really want to chase this down, you can do the same thing I did.
You'll be surprised at how little it takes to get that last step going.
Usually, it's something very simple. I think it would be nice to have
coreboot+plan 9+x220 working. We could then even consider using a 4 byte
address SPI part and put Plan 9 boot file system in firmware :-)

A handy way to test things out is to start up your x220, cpu in, and
experiment with poking the frame buffer. What has not been tried, but ought
to work, is cpu in, run linux in a vm, and let it bring the buffer up. That
would be really interesting.

On Sun, Nov 23, 2025 at 8:05 AM Emery <emery@slow.janky.email> wrote:

> With my x220 and coreboot the graphics are not initialized by 9front on
> coldboot.
> 
> if you boot into Linux, load the i915 module, then do a hot-reboot into
> 9front, then it works.
> 
> Cheers,
> Emery

------------------------------------------
9fans: 9fans
Permalink: https://9fans.topicbox.com/groups/9fans/T82d344ab9bb6e428-M7d1444d9bf25f89b711616cd
Delivery options: https://9fans.topicbox.com/groups/9fans/subscription

[-- Attachment #2: Type: text/html, Size: 4111 bytes --]