#9423 NORM 1.5-F11: Stabilize OFW USB handling on XO-1.5

[Zarro Boogs per Child]

#9423: Stabilize OFW USB handling on XO-1.5
-------------------------------------------+--------------------------------
           Reporter:  wmb at firmworks.com    |       Owner:  wmb at firmworks.com
               Type:  defect               |      Status:  assigned         
           Priority:  normal               |   Milestone:  1.5-F11          
          Component:  ofw - open firmware  |     Version:  1.5-B2           
         Resolution:                       |    Keywords:                   
        Next_action:  test in release      |    Verified:  0                
Deployment_affected:                       |   Blockedby:                   
           Blocking:                       |  
-------------------------------------------+--------------------------------

Comment(by wmb at firmworks.com):

 After a lot of experimentation, I was unable to find any software change
 that prevents the timeout with the Kingston key.  But the key works fine
 if you just retry the command after the first timeout, so I changed the
 USB mass storage driver to so such a retry.  That seems to be effective in
 making booting from USB reliable on that key - I have run about 60 test
 cycles with the retry code, which is about 10 times the mean time to
 failure for the non-retry case.  The timeout is a lot shorter now so the
 retry isn't too painful.

 I have a question out to Via to see if there are hardware or chip tuning
 things we can do to reduce the likelihood of the bus condition that causes
 the timeout.  Meanwhile, this retry fix (svn 1449) will go in q3a15 to
 stabilize the system operation as seen by the user.

-- 
Ticket URL: <http://dev.laptop.org/ticket/9423#comment:7>
One Laptop Per Child <http://laptop.org/>
OLPC bug tracking system