[coreboot] Where is the first instrucion?

Rafael Machado rafaelrodrigues.machado at gmail.com
Sun Jan 10 12:27:32 CET 2016

Hi Peter and Rudolf.
Thanks for the answers and tips. They are realy helpfull !
I'll take a look.

Rafael R. Machado

Em Sáb, 9 de jan de 2016 17:19, Rudolf Marek <r.marek at assembler.cz>

> Hi,
> I guess your question is more general than the coreboot related right?
> If you have a firmware image dump of the flash (not the file you download
> from
> board vendor) then yes, first location to be executed is the instruction
> located
> 16 bytes before end of the image.
> In coreboot see in build/ bootblock_inc.S which also has reset16.inc and
> entry16.inc which is a real start. Consult the Intel or AMD manual to see
> the
> CPU state after reset. The CPU starts in real mode, but CS base is shifted
> to
> last 64KB before end of 4GB address space. In general your CPU starts in
> compatible mode with 8086 manufactured in 1978.
> Thanks
> Rudolf
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.coreboot.org/pipermail/coreboot/attachments/20160110/8475cce7/attachment.html>

More information about the coreboot mailing list