Re: framebuffer and ggi

["Adam C. Powell, IV" <adam powell nist gov>]

Vignaud Jean-Baptiste wrote:

> >
> >
> > Check this out, this might help you:
> > http://www.alphalinux.org/docs/fbcon_faq.shtml
> >
> I'v checked this, but i have some questions:
>
> I first compiled the matroxfb in module mode, and after a modprobe the
> screen goes covered by stranges pixels, the box was frozen, only a hard
> reset unlock it.

Did you set a mode for the fb to start in?  For example, "modprobe matroxfb
vesa=0x318" (this works with insmod, but I'm not sure about modprobe).

> I'v compiled it in the kernel and added video:vesa:0x318. This time the
> kernel booted correctly, and cat /proc/fb gives me '0 MATROX VGA'.

Really?  That's interesting, because it sounds like you're using the vesafb
and not matroxfb.  The equivalent to use matroxfb would be
"video=matroxfb:vesa:0x118".  Nonetheless, two interesting points:

   * vesafb works on SX/matrox
   * it boots in graphic mode

matroxfb hangs for me on LX when trying to boot in any graphic mode, but boots
fine in text mode, then I switch mode later using fbset.

> Any trie to use fbset results in an error like SETMODE something (dont
> remember the exact error code)

Are you using "-accel true" with fbset as is suggested in the FAQ?  This also
could be a vesafb/matroxfb issue...

> I'v downloaded the latest version of ggi (degas snapshot of yesterday) and
> compiled libggi with kgi and fbcon support.
>
> All tries to run a demo result in the same error than with fbset.

I don't know of any analogy to fbset's -accel in ggi, so I'd guess again
vesafb/matroxfb.

> I' compiled the kgicon module (after fixing a 'register' problem in
> <asm/current.h> changing "register struct task_struct *current
> __asm__("$8");" to "struct task_struct *current __asm__("$8");" maybe this
> was not the correct way to fix the error...), i'v compiled the utils part of
> the kgicon, instaled the two .o in
> /lib/modules/.../video done a depmod -a and modprobe kgicon
>
> this results in a kernel 'oops':

I thought I heard a rumor that kgicon was no longer supported...

> Can someone give me an example of fbset parameter to change the mode of the
> matroxfb...

I use: fbset 1280x1024-60 -depth 24 -accel true

> My system is a SX164, redhat 5.2, kernel 2.3.6 and a matrox millenium II.

You see in here a lot of "I heard", "I thought".  This is more because I have
not been keeping up with the state-of-the-art nearly enough to give definitive
answers to your questions, and am probably very wrong on some of them.  You
should probably post to the linux-fbdev list (subscription info is given on
the FAQ for those interested), though beware: the number of experts in both
the framebuffer and Alpha is small enough that you will probably have to do
some hacking or digging through motherboard documentation to answer your
toughest questions.

Hopefully I've given you a couple of things to try so you can give linux-fbdev
the most thorough possible report.

Good luck, and if you make some progress, please let me know so the Alpha FAQ
remains current.

P.S.  Part of the problem is that there are several different sources of
documentation, including the faq on ALO, the "official" howto linked from it
(which I only became aware of recently), and the kernel Documentation/fb
directory.  Reading every detail of every piece of every howto on the net just
isn't an option, especially when they're in a foreign language, even more so
when they contradict each other.  Hopefully the "official" howto will become
more complete so the ALO one can go away and things will be more centralized
and consistent.  But the maintainer hasn't replied to my patch of over a week
ago, so it seems ours will remain for some time...

Zeen,

-Adam `Cold Fusion' Powell, IV http://www.ctcms.nist.gov/~powell/ ____
USDoC, National Institute of Standards & Technology (NIST)  |\ ||<  |
Center for Theoretical and Computational Materials Science  | \||_> |