Re: drm/radeon/kms: pm: single frame corruptions on reclocking

[Alex D. <ale...@gm...>]

2009/12/23 Rafał Miłecki <za...@gm...>:
> I applied patches from http://www.botchco.com/alex/xorg/pm/ and now
> engine reclocks between 110MHz and 680MHz.
>
> The problem is I see ~10 black horizontal lines for a one frame time
> on almost every reclock. I tried to fix this or at least understand it
> somehow but without success.
>
> 1) Putting 500ms delay after every reclock doesn't improve anything
> 2) Reclocking between 110MHz and 130MHz (instead 680MHz) doesn't improve
> 3) Calling atombios_crtc_set_pll after reclocking doesn't improve

No need to mess with the pixel clocks.

> 4) Calling ClockSource AtomBIOS commane after reclocking doesn't improve
>

You shouldn't need to mess with this either.

> Do you have any other ideas?

I suspect the reclock is missing the blanking period.  Try removing
the debugging output in my patch as that adds additional latency.
Also, if the latency of the reclock is too long, we may want to
trigger the reclock on a vline irq say 3/4 of the way down the screen
to give us some additional time.

Alex