#11089 HIGH 1.75-fi: XO-1.75 B1 brick after RTC power fail due to efface-md failure to flash-open

[Zarro Boogs per Child]

#11089: XO-1.75 B1 brick after RTC power fail due to efface-md failure to flash-
open
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           Reporter:  Quozl                |       Owner:  wmb at firmworks.com
               Type:  defect               |      Status:  new              
           Priority:  high                 |   Milestone:  1.75-firmware    
          Component:  ofw - open firmware  |     Version:  1.75-B1          
         Resolution:                       |    Keywords:                   
        Next_action:  diagnose             |    Verified:  0                
Deployment_affected:                       |   Blockedby:                   
           Blocking:                       |  
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Comment(by wmb at firmworks.com):

 In initial bringup, I had problems with SPI initialization - sometimes it
 would work and sometimes it wouldn't.  This was in the CForth realm, which
 has to access the SPI FLASH several times.  I suspect that this may be a
 similar problem.  My guess is that the SPI interface hardware might have
 an extra byte stuck in the FIFO, confusing the SPI device identification
 code.  I'm not sure why it works with q4b02d and fails with q4b05, but I
 suspect that bisection is not the best approach.  My plan is to debug spi-
 start in the failing case and check the status of the SSP hardware,
 looking for initialization glitches.

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Ticket URL: <http://dev.laptop.org/ticket/11089#comment:1>
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