Re: [forum] Driver development vs X development

["Kendall Bennett" <KendallB@scitechsoft.com>]

Billy Biggs <vektor@dumbterm.net> wrote:

>   The difference between XFree86 and the kernel is that projects
> like the video players, DirectFB, and Fresco, would benefit from
> drivers that did not rely on an X server, so I see build separation
> as having benefits for beginning on this goal as well. 

Definately. In fact that was the whole point of us developing the 
original VESA VBE/AF specification many years ago, to get a clean 
separation not just between XFree86 and the drivers but between the 
entire *OS* and the drivers. Unfortunately nobody seemed to realise the 
value of what I was trying to create back then (and yes, we did have 
members of the XFree86 group come to a few VESA meetings back then). Also 
many of the hardware vendors were scared stiff of being seen doing 
something that would allow non-Windows operating systems to use their 
drivers, so VBE/AF 2.0 (the first really useful version) never made it to 
completion.

The culmination of this is now SciTech SNAP, and we are gearing up to 
beta test our Linux XFree86 based solution soon. With XFree86 running on 
top of SciTech SNAP, you get a system where XFree86 is using a binary 
portable device driver technology that is completely separate from 
XFree86, and in fact completely separate from any specific OS (it is just 
CPU architecture specific, such that the current drivers run on any x86 
based OS, but a DEC Alpha and PowerPC ports are already in the works due 
to Amiga licensing the technology for their next generation OS). The 
exact same driver binaries that are used to support XFree86 on Linux are 
the same binaries used to support our Windows 9x, Windows 2000, OS/2, QNX 
and embedded systems products! Right now we are concentrating on Linux, 
but the PM library layers can easily be ported to run on FreeBSD also. On 
the Linux platform however, the drivers are used by XFree86 but you can 
also code directly to the SNAP API's or use a library such as our SciTech 
MGL library. A long time ago we had an SVGALib driver that used a 
previous version of SciTech SNAP, and there is interest in reviving this 
again. In essence SVGALib, SDL, GGI, DirectFB etc can all utilise this 
same device driver model to get graphics support on the Linux platform.

You could even load the drivers in the Linux kernel; all you would need 
to do is provide a PM (Portability Manager) library implementation in the 
Linux kernel. Although personally I don't thinka full featured graphics 
driver is useful in the kernel, but rather the kernel modules should be 
just very low level DMA/interrupt handling modules with all the real work 
done in userland.

You can find out more about SciTech SNAP from our web site, and you can 
download the current GPL version of the SDK as well (the GPL DDK is still 
being prepared for release):

http://www.scitechsoft.com/products/embedded/sdk_home.html

Regards,

---
Kendall Bennett
Chief Executive Officer
SciTech Software, Inc.
Phone: (530) 894 8400
http://www.scitechsoft.com

~ SciTech SNAP - The future of device driver technology! ~