[ECOS] PC STARTUP OPTIONS

[Stephen Polkowski <stephen at centtech dot com>]

Hello all,

	I've been wanting to make some changes on the PC platform that would 
improve the loading formats.  Currently, we have STARTUP_FLOPPY and 
STARTUP_RAM, STARTUP_ROM isn't really finished yet.  The FLOPPY option 
can only load a image into the lower 1 Meg of RAM, while the RAM version 
can only load above 1 Meg.

	First, it would be nice if we could load a image to any location via the 
FLOPPY.  The FLOPPY code is in real mode so it isn't possible. So, I am 
proposing that we add a RELOCATE section to the startup code.
The relocate section would switch into protect mode, relocate the code,
and then jump to the new code area.  The relocate code will check the 
current execution address against the _start address.  If they differ, 
the relocation code will move the image to the _start address.

	Having a relocate section could solve several problems.  First, it would 
make it possible to load an image to the upper 1 meg.  Second, it would 
make ROMRAM possible. Lastly, the relcate code would be the first set in 
making a REDBOOT flash option possible on the PC platform.

	Would anyone be interested in this change?  I could probably have this 
working in a few days.  Any takers?

Thanks,

Steve


		


-- 
Stephen Polkowski
Centaur Technology
Austin, TX
(512) 418-5730


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