[Trac #185] Need better SPI FLASH recovery procedure

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#185: Need better SPI FLASH recovery procedure
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 Reporter:  wmb at firmworks.com  |        Owner:  wmb at firmworks.com
     Type:  task               |       Status:  new              
 Priority:  high               |    Milestone:  BTest-1          
Component:  linuxbios          |   Resolution:                   
 Keywords:                     |  
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Comment (by wmb at firmworks.com):

 I now have a version of the recovery program that runs under Linux.  Write
 performance is pretty good - reprogramming the whole thing takes 3+
 minutes as with the standalone version.  But read/verify performance
 sucks.  It takes 2.5x longer than it should - 17 minutes instead of 7.
 The problem appears to be that reading a character from the serial driver
 causes a scheduling event, so the program doesn't wake up until the next 1
 millisecond boundary.  So instead of being able to read 2500 bytes per
 second (115200 baud is about 10K characters/sec, and each FLASH read moves
 4 bytes over the serial line - 3 out and 1 in), you only get to read 1000
 bytes per second.

 I don't think that the kernel I'm using has the fast scheduling patch...

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Ticket URL: <http://dev.laptop.org/ticket/185#comment:2>
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