[Trac #60] Resume from RAM

[Zarro Boogs per Child]

#60: Resume from RAM
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 Reporter:  wmb at firmworks.com  |        Owner:  wmb at firmworks.com
     Type:  enhancement        |       Status:  assigned         
 Priority:  high               |    Milestone:  BTest-1          
Component:  kernel             |   Resolution:                   
 Keywords:                     |  
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Comment (by wmb at firmworks.com):

 What Linux needs to do to use the wakeup-via-LinuxBIOS patch:

 During the suspend-to-RAM sequence, Linux should:

 * Save any important data at locations 0 and 4
 * Write the wakeup entry point address to location 4 (long)
 * Write 0x51ee4129 to location 0.

 When LinuxBIOS comes out of reset upon waking up, it will turn on the
 memory controller and check for that signature at location 0.  Upon seeing
 it, LinuxBIOS will jump to the address that is stored at location 4.
 LinuxBIOS doesn't set any of the other registers to specific values.  The
 only guarantee is that the system is in 32-bit protected mode with 4GB
 identity-mapped code and data segments.

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Ticket URL: <http://dev.laptop.org/ticket/60#comment:7>
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