#10457 NORM Not Tri: Occasional SD command timeouts in OFW on XO-1.75

[Zarro Boogs per Child]

#10457: Occasional SD command timeouts in OFW on XO-1.75
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           Reporter:  wad        |       Owner:  wad        
               Type:  defect     |      Status:  new        
           Priority:  normal     |   Milestone:  Not Triaged
          Component:  hardware   |     Version:  1.75-A1    
         Resolution:             |    Keywords:  XO-1.75    
        Next_action:  reproduce  |    Verified:  0          
Deployment_affected:             |   Blockedby:             
           Blocking:             |  
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Comment(by wad):

 With board #12, I got 25MHz operation working reliably using the following
 delay values (SDCLOCK_SEL = 1 and SDCLOCK_DELAY = 0x12):

  dev /sd true to avoid-high-speed?
  : cco h# 10a cw@ h# 2500 or h# 10a cw! card-clock-on ;
  patch cco card-clock-on card-clock-25
  dend

 And I was able to get 50 MHz operation running with this patch
 (SDCLOCK_SEL = 1 and SDCLOCK_DELAY = 0x1F):


  dev /sd
  : cco h# 10a cw@ h# 3F00 or h# 10a cw! card-clock-on ;
  patch cco card-clock-on card-clock-50
  dend

-- 
Ticket URL: <http://dev.laptop.org/ticket/10457#comment:2>
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