[U-Boot] [PATCH] remove (double) LED initialization in arm920t start.s

Andreas Bießmann andreas.devel at googlemail.com
Thu Dec 23 12:58:34 CET 2010


Dear Jens Scharsig,

Am 18.12.2010 um 13:08 schrieb Jens Scharsig:

> * remove LED initialization in front of relocation and bss init
> 
> Signed-off-by: Jens Scharsig <js_at_ng at scharsoft.de>
> ---
> 
> * prevents run C function on an uninitialized environment

You are right, we do not have stack/bss setup when we call these two c-functions.

But in that case it is ok to do so cause we do just pc relative accesses here, do not use bss variables and last we do not use the stack.

Beside the fact that we could use it here as it is done since atmel posted their at91rm9200 code we could ask if we need it or not.

I think it is a nice helper for initialisation debugging and I used it from time to time for my relocation investigations. But I think we do _not_ need it in every arm920t/at91 board for every bootup.
It should be
 a) enclosed in some ifdef to enable them conditionally on compile time
 b) documented in a README and completely removed (some lines later too)

Beside that one could state
 c) completely removed (the whole coloured_LED stuff) as this is atmel specific and other SoC use another interface to switch LED
if we decide to not use these LED features for bootup debugging.

AFAIK this is also used in arm926ejs (at91sam only), Reinhard can you please comment on that?

regards

Andreas Bießmann


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