Re: Sec and Reset vector

[Marvin H?user <Marvin.Haeuser@outlook.com>]

Hey Rafael,

There actually is some generic SEC code in UefiCpuPkg you might want to take a look at. It's generic because it does not have "Intel NDA" code, such as CAR (Cache-As-RAM) etc.
The Reset Vector may or may not be part of SecCore. It's either embedded within the SecCore module, or a separate file in the FFS. You can check the start/end address of the modules (e.g. with UEFITool) and find the Reset Vector file that way.

PS.: Seems like inline images are not supported by the mailing list (or is it my error?). Either way, I do not see the image in my mail client (Outlook 2016).

Regards,
Marvin.

> -----Original Message-----
> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of
> Rafael Machado
> Sent: Saturday, October 22, 2016 6:28 PM
> To: edk2-devel@lists.01.org
> Subject: [edk2] Sec and Reset vector
> 
> Hi eveyrone
> 
> I'm doing some studies on edk2 and coreboot, but I'm having some questions
> that I believe you can help.
> 
> On the journey to try to understand things since the beginning, so they make
> sense in future, I'm trying to understand how does the Initial phases of UEFI
> / PI firmware work. To do that I got a bios image and start to reverse it to
> check the modules and everything present at that bios. Now I understand, at
> least the basics, about DXE and PEI phase.
> 
> The main question that I have now is about the SEC phase.
> To try to understand the SEC phase I tried to reverse this firmware so I could
> check the reset vector's first jump or something like that.
> The surprise I have is that I was not able to find this code.
> 
> To be sure I was reversing on the correct way I generated a coreboot image.
> On the image below we can see the initial code of a firmware generated
> using coreboot
> 
> [image: pasted1]
> 
> But at the UEFI firmware I'm studying I'm not able to find anything similar to
> that.
> My guess before starting this was that at least the SEC initial code should be
> similar to the legacy way of doing things, a jmp at 0xfff:fff0 and after that the
> magic should get started with all uefi phases.
> 
> Could someone please give me some light on that?
> 
> 
> Thanks and Regards
> Rafael R. Machado
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