Re: Re: But *why* no vblank?

On Mit, 2002-11-06 at 18:04, Keith Packard wrote:
> Around 16 o'clock on Nov 6, Michel =?ISO-8859-1?Q?D=E4nzer?= wrote:
> 
> > Okay, is there anything wrong with turning the struct for the ioctl into
> > a union of a request and a reply struct? :)
> 
> That is the usual way, I believe...  Or, you can just build a larger 
> struct containing both pieces.
> 
> > Yes. The blocking ioctl also returns a timestamp, is that important for
> > the signal?
> 
> Might be nice; there's plenty of space.  Is it expensive to compute?
> 
> > Oh, and BTW, is it okay for the ioctl to trigger a single signal, or
> > would it have to generate signals indefinitely?
> 
> Might want a mode that chose between these two options, but if I had to 
> pick one, I'd ask for a single signal.  That's what SYNC wants.

http://penguinppc.org/~daenzer/DRI/radeon-vbl-signal.diff

is an attempt at this, unfortunately not successful - it locks up solid
when I request a signal to be delivered. Now I'd very much like to get
this into 4.3.0, so I'd appreciate someone pointing out the stupid
mistake(s) I'm probably making. :)


-- 
Earthling Michel Dänzer (MrCooper)/ Debian GNU/Linux (powerpc) developer
XFree86 and DRI project member   /  CS student, Free Software enthusiast