#9883 HIGH 1.5-sof: random coloured dots and old frame buffer image on vt1 on idle suspend

[Zarro Boogs per Child]

#9883: random coloured dots and old frame buffer image on vt1 on idle suspend
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           Reporter:  Quozl            |       Owner:  cjb                              
               Type:  defect           |      Status:  new                              
           Priority:  high             |   Milestone:  1.5-software-update              
          Component:  x window system  |     Version:  Development build as of this date
         Resolution:                   |    Keywords:  XO-1.5 suspend DCON              
        Next_action:  design           |    Verified:  0                                
Deployment_affected:                   |   Blockedby:                                   
           Blocking:                   |  
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Changes (by wad):

  * next_action:  never set => design
 * cc: pgf (added)
  * priority:  normal => high
  * version:  not specified => Development build as of this date
  * milestone:  Not Triaged => 1.5-software-update
  * keywords:  => XO-1.5 suspend DCON


Comment:

 This is not the first time that we have seen DCON freeze produce random
 noise on the screen.   What is happening is that for some reason, the DCON
 is being told to grab video when the video is "out of spec" (usually due
 to a timing problem).

 My suspicion is that or some reason, the VX855 frame buffer is turning off
 before the DCON has completed its load of the video data.   The frame
 buffer must not be touched until after the DCON grab has completed.

 Looking at the attached dmesg, the delays due to libertas failure may be
 delaying the DCON grab.

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Ticket URL: <http://dev.laptop.org/ticket/9883#comment:3>
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