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<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">Hi,</DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif"> </DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">I understand the procedure in which internally how the CS register ( Segment selector and base address part) make sure that we point to the address 0xFFFFFFF0.</DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif"> </DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">But my doubts are in this part.</DIV>
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<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">1) We will be flashing the coreboot.rom into the BIOS flash, right ?</DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif"> </DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">2) If we objdump coreboot.rom, dump all the sections, we dont see the reset vector part and also the address 0xFFFFFFF0.This could be because these sections are stripped off.Is it because of that ?</DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif"> </DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">4) If they are stripped off, then when I flash the coreboot.rom, what do I flash into the address 0xFFFFFFF0, as the coreboot.rom doesnt even contain the data(opcodes ) to write in that location.</DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif"> </DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">Am I missing anything.</DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif"> </DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">Regards,</DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">Viswesh</DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif"> </DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">ps:- I am trying to correlate my experience in embedded firmware exp, where the files we were flashing had absolute addresses and we could objdump the flash file to understand the code at each location.</DIV>
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<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif">Message: 5<BR>Date: Wed, 26 Mar 2008 00:40:21 +0100<BR>From: Peter Stuge <<A href="mailto:peter@stuge.se" ymailto="mailto:peter@stuge.se">peter@stuge.se</A>><BR>Subject: Re: [coreboot] Code flow from reset vector<BR>To: <A href="mailto:coreboot@coreboot.org" ymailto="mailto:coreboot@coreboot.org">coreboot@coreboot.org</A><BR>Message-ID: <<A href="mailto:20080325234021.15330.qmail@stuge.se" ymailto="mailto:20080325234021.15330.qmail@stuge.se">20080325234021.15330.qmail@stuge.se</A>><BR>Content-Type: text/plain; charset=us-ascii<BR><BR>On Tue, Mar 25, 2008 at 12:02:15PM -0700, Viswesh S wrote:<BR>> I understand the coreboot.rom is the BIOS code, which comes inside<BR>> the address mapped in real mode.( 0xA0000 - 0x100000).<BR><BR>Mh, not only.<BR><BR><BR>> If that is the case, then how do we write into the address<BR>> 0xFFFFFFF0, while we flash the
BIOS.<BR><BR>386 and up power up with CS set specially so that it "points" at<BR>physical address 0xffff0000. Similar to the flat real mode idea.<BR><BR>A far/long jump changes CS into plain real mode so a far jump is<BR>pretty common early in the boot process.<BR><BR><BR>//Peter<BR><BR><BR><BR>------------------------------<BR><BR></DIV></DIV></div><br>
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