From: Johan Karlberg <wlfshmn@failure.aroundit.com>
  To  : ggi-develop@eskimo.com
  Date: Thu, 25 Mar 1999 07:11:56 +0100 (CET)

Re: Linus on linuxworld

On Wed, 24 Mar 1999, Josh wrote:

> 
> 
> On Wed, 24 Mar 1999, Sengan Baring-Gould wrote:
> 
> > http://www.linuxworld.com/linuxworld/lw-1999-03/lw-03-opensources.html
> > 
> > Rule number 1 for keeping the kernel healthy: avoid new system interfaces.
> > Once you give an interface to users they will start coding to it and once
> > somebody starts coding to it you are stuck with it. Do you want to support
> > the exact same interface for the rest of your system's life?
> > 
> > Given that graphics evolves very quickly, isn't the above actually rather
> > hard
> > to achieve beyond a framebuffer?
> > 
> > Sengan
> 
> 
> 
> I've just started getting into the ggi project, so I'm not in any position
> to dictate where ggi should go, but it seems like the logical thing to do
> is to make kgi the absolute minimal driver. Maybe setSaneMode() (in the
> case that something gets hosed), saveState(), restoreState(), setMode(),
> and a few setVideoRegister()/getVideoRegister() functions that disallow
> invalid/destructive register settings.  This way the kernel API is
> minimal, and all the real work is done in user space.
> 
> I haven't checked out the kgi drivers yet, so this may already be the
> case.  
> 
> 
> In any event, I applaud the ggi project.  The linux kernel is
> fundamentally broken.  It's purpose is to abstract the hardware so that
> applications may make use of it effectively, and it fails in the area of
> video cards.  It's like not supporting sound cards because the PC speaker
> is sufficient to produce error bells.  fbcon is better than just text
> mode, but it's rudamentary at best.
> 
> Josh
>   
> 
Yes, the minimal KGI driver you are talking about is pretty much our ideal
driver, for the ideal hardware in an ideal world. Unfortunatley however,
many a hardware out there has no way for you to safely export acceleration
registers to userspace while also guaranteeeing that a user cannot lock
upo the graphics card or acceleration engine, thus leaving the system
unusable. On some hardware, Matrox cmes to mind, it is supposedly possible
to export acceleration registers safely, and in such a case, it is the way
it is supposed to be done. a minimal kernel driver and acceleration in the
ggi stubs. On most hardware that is buggy or poorly designed (S3 comes to
mind here, alsthough not exclusivly in anyway) we will have to have
acceleration in the kernel, or not at all, in order to maintain system
integrity.

johan Karlberg