[U-Boot] Separately compile Master boot loader

[Albert ARIBAUD]

Hi Rajdeep,

On Tue, 9 Jul 2013 16:12:14 +0530, Rajdeep Vaghasia
<rajdeep.vaghasia at gmail.com> wrote:

> Hi
> I am working on one board with an arm11 based cpu, NOR flash and DDR2 SDRAM.
> When I compile u-boot source code, I get u-boot.bin image generated.
> This image has primary(second stage) and secondary(third stage) bootloader
> combined.
> 
> I have following queries:
> 1) The question that still eats me everyday is, How can I compile
> primary(Master) boot loader and secondary boot loader separately?
> 2) I want to Flash only initial 4kb of code (Master boot loader or second
> stage). The remaining code I want to keep at another partition in the
> Flash. How can I achieve this?
> 3) Is there any separate code available for Master boot loader, which
> copies the third stage bootloader to SDRAM and then transfers control to
> that third stage boot loader(u-boot)?
> 
> I am unable to find a way to do this.
> 
> Can anyone help me please?

Since you do not indicate exactly which target you're building, I'll
assume it is one with SPL (what you describe as master or second stage,
with third stage being u-boot itself).

I don't know of a way to build SPL alone.

As for building separate U-Boot and SPL, you'll find them in ELF format
in file ./u-boot and ./spl/u-boot-spl. You can then use
$(CROSS_COMPILE)objcopy to convert from ELF to .bin.

Note that your target may need a specific format different from the
pure binary that objcopy can produce.

Can you tell us more about your target?

Amicalement,
-- 
Albert.