On Wed, 19 May 2010 20:10:49 +0200 (CEST) Mark Kettenis
<mark.kette...@xs4all.nl> wrote:
> > When testing code controlling video/graphics hardware, you should
> > power off the system after hitting an error. The reason is simple;
> > the hardware/memory is no longer in a know state, so you no longer
> > know what you are testing, and hence, you may not be able to isolate
> > *repeatable* errors.
>
> Sorry, J.C. but you're wrong here. While it is possible to get
> hardware in a state that requires a full powercycle to get into a sane
> state, the intel video stuff will work fine again after a reboot.
Yep, I might be wrong in some cases. You could be right regarding the
newer intel Gen3/Gen4/Gen5 (915) and above stuff where a warm reboot
will suffice, but the early Gen1/810/815 and Gen2/830/845/85x/865
designs are just ugly. After a hard crash, a warm reboot (or worse even
cold reboot) will occasionally show "ghosting" of what was previously on
the display prior to the crash. It's pretty rare, but it happens, and
it's a know issue.
Though you can probably get away with a warm reboot some of the time on
some of the implementations of some of the intel chipsets, it just makes
sense to be cautious while testing. It doesn't make any sense to waste
my time (or worse, wasting someone else's time) with a bad core caused
by *me* failing to do everything I could to make sure the hardware was
in a good known state at the start. --If I sent you or matthieu@ or oga@
or whoever a bad core file caused by my mistake, you'd make me regret
it when it came time to pay for the beer. ;)
jcr
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