[OLPC-devel] Re: [One Laptop Per Child] #53: LinuxBIOS sometimes hangs after "Jumping to LinuxBIOS"

[Zarro Boogs per Child]

#53: LinuxBIOS sometimes hangs after "Jumping to LinuxBIOS"
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 Reporter:  wmb at firmworks.com  |        Owner:  rminnich
     Type:  defect             |       Status:  new     
 Priority:  major              |    Milestone:          
Component:  linuxbios          |   Resolution:          
 Keywords:                     |  
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Comment (by JordanCrouse):

 On my pre-reva board, after a warm reboot, the first byte copied from the
 ROM to RAM is invalid (0xFF instead of 0xFA) which ends up causing the
 hang.

 We thought that this might be due to cache corrruption since the warm-boot
 path doesn't turn off caches before jumping to {{{__main}}}, but sticking
 in wminvd before the copy doesn't seem to help.  I also note the
 following:

 * The 'warm reboot' issue only happens when I boot into the main kernel -
 rebooting from the ROM image works every time.

 * The corruption doesn't occur when I single step through the code - this
 is why we thought it would be the cache, since single step debugging tends
 to affect caching.

-- 
Ticket URL: <http://dev.laptop.org/ticket/53#comment:12>
One Laptop Per Child <http://laptop.org/>