[U-Boot-Users] Setting entry point in u-boot standalone apps

[Martin Krause]

Hi David,

u-boot-users-bounces at lists.sourceforge.net wrote on :
> I have a U-boot standalone app which runs on the Gumstix boards. 
> It's based on the /u-boot-1.2.0/examples/ folder.  The problem I have
> is that my entry 
> function - lets call it app_entry() - isn't at the load address, it's
> somewhere in the middle.  I'm using the output from objdump -d <elf

This is a known issue, please look at:
http://www.denx.de/wiki/view/DULG/MyStandaloneProgramDoesNotWork

> app no longer worked.  After investigating I found that I needed to
> disassemble the file, locate where the entry function is now located,
> and do the following commands:
> 
> loadb a0000000
> <send the .bin file>
> go a0000948 (or whatever the address of my entry function was)
> 
> This then worked every time.

Yes, it should :-)

> The -e part should be specifying the entry point of the ELF file,

Yes, it specifies the entry point (= entry function) - but not at which
address the entry point is placed by the linker. So the entry option 
does not, what you are looking for.

> Unfortunately, the examples don't use linker scripts, and I don't want
> to start messing with these as it interacts with u-boot to some extent
> (certainly built within u-boot's makefile), and it's all working as it
> is.  From what I understand though, the -e option should be
> sufficient. 

No, see comments above.

> Has anyone else experienced this problem, and can give any advice as
> to 
> how to solve it?

You have to change your linker script. Tell the linker where it should
place your entry point function (I'm no linker expert, so I couldn't 
give you advice at this ...)

Regards,

Martin Krause

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