From mboxrd@z Thu Jan  1 00:00:00 1970
From: David du Colombier <0intro@gmail.com>
To: 9fans@9fans.net
Date: Sun,  6 Jun 2010 22:13:22 +0200
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Subject: Re: [9fans] [frank@inua.be: Re:  no frame buffer]
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> I googled for AMD GX2 graphics processor and the first result led to:
> http://plan9.bell-labs.com/wiki/plan9/Supported_PC_hardware/index.html
>
> ...
> The following cards are known not to work with VESA:
>
> ...snip...
>     * AMD Geode GX2. Blank screen. Bug identified by Russ Cox, but hard to
> solve. ...

I am the one who wrote that on the Plan 9 Wiki.

I encountered this problem with my WYSE Winterm 9150SE
two years ago.

Russ Cox helped me to work on that problem.

As far I remember, the problem is the function vbecall
(/sys/src/cmd/aux/vga/vesa.c) never return.

VESA call need to switch to real mode, but getting out
from it only work on some machines.

According to Russ Cox, the fix is to change the
kernel's bios execution to use either VM86 mode
or a software x86 emulator.

--
David du Colombier