[U-Boot] [PATCH 2/2] hello_world.c: fix entry point in case of arm thumb binary

[Wolfgang Denk]

Dear Max,

In message <20170812090346.7887-3-max.krummenacher at toradex.com> you wrote:
> If compiling for thumb the U-Boot 'go' command can not jump to the entry
> point, as the jump will be done in the assumption that the code jumped to
> is using the arm instruction set.
> 
> So add add a simple forwarder in arm instruction set which then jumps
> to the 'real' entry.

This description makes no sense to me.  Whatever you do, the address
where the image starts executuin is what is called the entry point.
Whether this is needs special code to swutch to thumb mode or not
does not make any difference.  Whichever address you use with the
"go" command is the "entry point".

Also, can the mode switching not be done inside the body of the
regular hello_world() function?  This would be much better as it
wuld allow to always use the same method to determine the entry
point address (line running "nm" on the binary and grepping for the
name "hello_world").  With your code, you would have to fix all
documentation and explain that the entry pooint name is suddenly
domething totally different (and an unexpected, unusal name like
"dummy2" as well) for thumb images.

Sorry, but this does not seem a good idea to me.

Naked-by: Wolfgang Denk <wd at denx.de>

Best regards,

Wolfgang Denk

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