#9972 NORM 1.5-sof: openfirmware writes fail on an ext2 filesystem with large_file feature set

[Zarro Boogs per Child]

#9972: openfirmware writes fail on an ext2 filesystem with large_file feature set
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           Reporter:  Quozl                |       Owner:  wmb at firmworks.com                
               Type:  defect               |      Status:  assigned                         
           Priority:  normal               |   Milestone:  1.5-software-update              
          Component:  ofw - open firmware  |     Version:  Development build as of this date
         Resolution:                       |    Keywords:                                   
        Next_action:  add to build         |    Verified:  0                                
Deployment_affected:                       |   Blockedby:                                   
           Blocking:                       |  
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Comment(by wmb at firmworks.com):

 Detailed analysis of the block data traffic on that USB stick showed
 several cases where the data that read from a block disagreed with the
 previous write to that block.

 We tried two strategies to correct the problem, both to no avail:

 * Changed the partition map so the first partition started at 4 MiB (was
 sector 1), so subsequent multi-block writes were better aligned with
 respect to internal NAND pages
 * Reduced "max-transfer" in the USB disk driver node to 4 KiB (from 16
 KiB)

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Ticket URL: <http://dev.laptop.org/ticket/9972#comment:21>
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