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[John Rigby <732912@xxxxxxxxxxxxxxxxxx>]

In response to Jamie's question (Amitk will know better).  Display
driver hw sucks from ram and blows to an lcd or other graphics . It has
to keep up a certain speed to keep the output side happy.  To deal with
occasional starving on the input side there is usually a fifo.  A deeper
fifo can help smooth out times when the bus on the input side is over
taxed like when some other higher priority block is using lots of memory
band width.  When the fifo goes completely empty and cannot provide data
fast enough for the output that is an underflow which what is happening
here.

So the interesting new bit of news is that this apparently happens with
the CPU_FREQ scheduler gets set to ondemand.  My understanding is that
should only be adjusting the CPU clock and not a peripheral clock like
the display controller.  So this "shouldn't happen".

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https://bugs.launchpad.net/bugs/732912

Title:
  omapdss DISPC error: GFX_FIFO_UNDERFLOW

Status in “linux-linaro-omap” package in Ubuntu:
  Confirmed

Bug description:
  observed using hwpack for omap3 dated 03102011, using the linaro-
  developer image dated 03102011

  The following message is found via dmesg shortly after boot

  [   76.143890] omapdss DISPC error: GFX_FIFO_UNDERFLOW, disabling GFX

  No other messages are seen related to this message. The system had
  completed booting, network was up and bash was just sitting at the
  prompt

  Further it seems out of the blue. The system had coml