Re: [PATCH] drm: tegra: Use framebuffer pitch as line stride

[Lucas Stach <dev-8ppwABl0HbeELgA04lAiVw@public.gmane.org>]

Am Dienstag, den 27.11.2012, 14:39 -0700 schrieb Stephen Warren:
> > For your viewing pleasure (and playing with my new phone) :-)
> > http://www.youtube.com/watch?v=ZJxJnONz7DA
> > 
> > The external monitor is 1920x1200 I believe.
> 
> Jon Mayo says the corruption in the video is display (memory fetch)
> underflow. Perhaps this is because (IIRC) the BCT I'm using on Cardhu
> programs the memory controller at a slow rate, and the bootloader and/or
> kernel is supposed to bump up the rate to the max, but that's not
> implemented anywhere yet upstream. If you're testing with "fastboot"
> instead of U-Boot, that might be re-programming the memory frequencies,
> and hence avoiding this.
> 
> I guess we have a fun time ahead of us with mode validation and memory
> controller programming.

Maybe it's not insufficient memory bandwidth, but just the request
missing the deadline in the memory controller. You may try to adjust the
values in reg MC_LATENCY_ALLOWANCE_DC_0_0
for example.

Regards,
Lucas