And then spake Matthias Urlichs as follows:
> >Basically, the problem is that the video card generates VBL interrupts,
> >but the kernel doesn't know what to do with these except on a couple
> >of old Apple cards.  The interrupts are therefore only enabled when
> >there is an ethernet card in the machine (all nubus interrupts are on
> >one wired-OR interrupt line to VIA2/RBV).
> In an ideal world, closing the card's driver should disable the interrupts,
> and booter should close all drivers. (Does it? I don't have the sources at
> hand.)

Mostly, I've found that closing the card's driver hangs the machine;
that is, if you try to use the video at all after having closed it.
Designing Cards & Drivers says something to the effect that a video driver
should put its card into a quiescent state when it is closed.

-Brian

-- 
Brian Gaeke, The Dimensional Gate Company    Internet E-Mail: <brg@dgate.org>
DGate.ORG system adminstrator / PGP 2.6.2 public key available via finger
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