#5391 BLOC Never A: Q2D05/6 bricks machines with bad RTC data

[Zarro Boogs per Child]

#5391: Q2D05/6 bricks machines with bad RTC data
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 Reporter:  wmb at firmworks.com    |       Owner:  wmb at firmworks.com
     Type:  defect               |      Status:  new              
 Priority:  blocker              |   Milestone:  Never Assigned   
Component:  ofw - open firmware  |     Version:  Q2D05            
 Keywords:                       |    Verified:  0                
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 Install Q2D05 or Q2D06 firmware.  Remove all power including the RTC
 battery.  Wait a couple of minutes for the RTC to discarge.  Reinstall the
 RTC battery and reconnect power.  Turn on the machine.  Congratulations,
 you have a brick.  The screen won't even come on.

 If you have a serial console, you can recover as follows:

 The last line on the serial console is
 Page Fault

 Do this:

 ok probe-pci probe-usb

 Now you can reload the firmware from one of the usual sources with the
 "flash" command.

 The root cause of this problem is a deficiency in the "factory-mode" code
 added by svn 736.  If the month value in the RTC is 0 (which is not in the
 valid range 1..12), the routine that converts the date to the "seconds
 since 1970" format accesses outside the valid range of the days per month
 table and faults.

 The fix is to force that value to be within the range 1-12 before
 accessing the table.

 This is a very bad bug and I will issue a new version with a fix
 immediately.

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Ticket URL: <http://dev.laptop.org/ticket/5391>
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