[U-Boot] SteppingStone

Wolfgang Denk
2011-01-26T09:41:33Z

Dear Cunsuo Guo,

In message <AANLkTin=D7T-JQB4BFNYiZPT8WbZX5Kjy-fqyabyZRAZ@mail.gmail.com> you wrote:
>
> > Why try to read from NAND to RAM in the relocation part of start.S,
> > where you would not be able to use C or BSS variables?
> >
> > Because S3C2410 can _ONLY_ take the first 4KBytes into RAM (Basically some
> hidden microcode in the S3C2410 takes care of copying the first 4KB of NAND
> flash into RAM), so the rest code must be relocated into RAM from NAND by
> the U-Boot code itself. Of course, there's no C environment set up yet, all
> job should be done by assembly code.

This is not really different from how NAND booting works on many other
boards.

It is definitely not a reason to use assembly only.

Instead, the standard nand_spl approach should be used.

Best regards,

Wolfgang Denk

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