#9589 LOW Opportu: OFW startup sound repeats if frame key hit after escape

[Zarro Boogs per Child]

#9589: OFW startup sound repeats if frame key hit after escape
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           Reporter:  Quozl                |       Owner:  wmb at firmworks.com      
               Type:  defect               |      Status:  assigned               
           Priority:  low                  |   Milestone:  Opportunity            
          Component:  ofw - open firmware  |     Version:  OFW development version
         Resolution:                       |    Keywords:                         
        Next_action:  design               |    Verified:  1                      
Deployment_affected:                       |   Blockedby:                         
           Blocking:                       |  
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Changes (by wmb at firmworks.com):

  * status:  new => assigned


Comment:

 The reason the sound continues on XO-1.5 but not on XO-1 is because the HD
 Audio hardware on XO-1.5 requires software intervention to stop playing
 once the sound has started, whereas AC97 hardware has "play once then
 stop" capability.  The frame key interrupt has the intentional side effect
 of disabling further interrupts until interrupts are manually re-enabled.
 When interrupts are disabled, the code that turns off the sound cannot
 run.

 scp dev.laptop.org:~wmb/q3a15b.rom  has a proposed fix for this - it locks
 out the frame-key (or serial break) interrupt until just before the ok
 prompt is issued.  As a an additional "feature", the sound stops
 immediately when the ok prompt is issued.

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Ticket URL: <http://dev.laptop.org/ticket/9589#comment:1>
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