Subject: Re: radeon driver design (was Re: generic virtual consoles)
To: Michael Lorenz <macallan@netbsd.org>
From: Thor Lancelot Simon <tls@rek.tjls.com>
List: tech-kern
Date: 12/22/2005 07:44:24
On Thu, Dec 22, 2005 at 06:54:30AM -0500, Michael Lorenz wrote:
> 
> > The end result will *not* be compatible with any current X11 driver. 
> > However, one could write a driver and probably even make it "safe" to
> > run unprivileged.
> 
> This would be a nice addition to XFree's wsfb driver. And handling
> acceleration in kernel would allow to queue blitter commands and use
> interrupts to run them asynchronously. Maybe there should be a simple
> packet format describing them ( like a command, plane mask, ROP,
> coordinates, other data, so it would easily be usable for X ) and an
> ioctl that simply takes a pointer to a buffer full of them, enqueues
> them and maybe sets completion flags.

This sounds eerily like the interface DEC used in Ultrix, sometime
in the late 1980s.  The pmax port implements the kernel side of that
interface, for some graphics hardware at least -- it might be worth
looking at.

I think it's also written up in at least one paper.

Thor