From: Andreas Beck <becka@rz.uni-duesseldorf.de>
  To  : ggi-develop@eskimo.com
  Date: Thu, 17 Jun 1999 19:12:55 +0200

Re: libGGI on matroxfb with Mystique

> > matroxfb allows you to mmap() the accel registers as well as the
> > framebuffer, so you just map it in and use the registers directly.
> Ah, my normal user has access to /dev/mem. 

No - that's not needed You need access to /dev/fb*. After the FB, the accel
regs are mapped.

> Do the kgi drivers work like this or are they kernel modules?

They are kernel modules, but they can as well do the same trick.

> > Currently either this, or use a separate frame for the source images
> > and blit from that (use ggiSetReadFrame to select the source frame).
> Which targets support accelerated ggiCopyBox?

Fbdev and xlib come to mind. Glide maybe ?

> The glide target worked very well and fast without DirectBuffer (using ggiPutBox for system
> backbuffer). But when I use DirectBuffer on it, it is much slower 66->20 fps.
> Maybe the system memory works as a buffer which handles
> the blits of small images better than writing each of them over the bus.
> Are there any MTRR regions I could set for my Voodoo2?

IIRC the Glide stuff starts to crawl when accessed as vidram. And if you
need a lot of lock/unlock that might take time as well.

CU, ANdy

-- 
= Andreas Beck                    |  Email :  <andreas.beck@ggi-project.org> =