olpc.fth

[Richard A. Smith]

On 02/03/2011 04:21 PM, Martin Langhoff wrote:
> On Thu, Feb 3, 2011 at 4:16 PM, Jerry Vonau<jvonau at shaw.ca>  wrote:
>> Just a quick question is it possible to run commands that are available
>> at OFW prompt inside the olpc.fth file? I'm looking at trying to run
>> add-tag-from-file from within olpc.fth.
>
> I used to think you could, but according to Reuben and Mitch... you
> can't. By the time boot.fth gets executed, OFW has put the memory back
> in readonly mode.
>
> So the add-tag game should be done with a proper keyjector.

It depends on the security mode.

If the laptop is secure then the flash ROM is write protected prior to 
the point at which olpc.fth is interpreted.  So although you can run all 
sorts of OFW commands you won't actually be able to change the flash. 
The only way to change the flash is to boot a firmware with code that 
modifies things prior to the write protect.

If the laptop is not secure then you can fire at will.  Most tag 
operations involve a reboot but later firmwares on the 1.5 have a 
special mode where you can write to the flash area without a reboot.

-- 
Richard A. Smith  <richard at laptop.org>
One Laptop per Child