[coreboot] Ok, let's move on. What shold we do to CBFS?

[Marc Jones]

Hi Hamo,


On Fri, May 13, 2011 at 11:07 PM, Hamo <hamo.by at gmail.com> wrote:
> Ping...
>
> On Wed, May 11, 2011 at 8:51 PM, Hamo <hamo.by at gmail.com> wrote:
>> Dear lists,
>> I have got the idea on how to deal with xcompile script for ARM. Now,
>> let's move on to CBFS.
>> It is one of the most difficult part since CBFS is almost hard-coded
>> to X86 architecture. On ARM,
>> we need CBFS like this:
>>
>>
>> /---------------\ <-- Start of ROM
>> | /-----------\ |
>> | | Reset  | | <- 0x0
>> | |-----------| |
>> | |IVs      | |
>> | |-----------| |
>> | |Boot    | |
>> | |Block   | |
>> | \-----------/ |
>> |               |
>> | /-----------\ | --|
>> | | Header| |   |
>> | |-----------| |   |
>> | | Name  | |   |
>> | |-----------| |   |-- Component
>> | |Data    | |   |
>> | |..         | |   |
>> | \-----------/ | --|
>> |               |
>> | ...           |
>> | /-----------\ | --|
>> | | Header| |   |
>> | |-----------| |   |
>> | | Name  | |   |
>> | |-----------| |   |-- Component
>> | |Data    | |   |
>> | |..         | |   |
>> | \-----------/ | --|
>> \---------------/
>>
>>
>> Where should we put the CBFS master header and the pointer to it?
>> I have no idea of how to implement it and not break it on X86
>> architecture. Any comment or suggestion is very welcome.
>>
>
>

It is good that you are starting to plan this. I think that the main
thing is to get an entrypoint that works for ARM. I would try to leave
the cbfs architecture in place and just add another entrypoint. The
x86 entrypoint starts at the top and jumps down, the ARM entrypoint
cold be located at 0x0 and jump to the same location that x86
entrypoint uses. I don't know if there is a problem with that.  What
are your ideas about this?

Stefan and Patrick might have some thoughts on this too.

Marc

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