[U-Boot] On simple standalone applications

[Alessio Sangalli <alesan@manoweb.com>]

Wolfgang Denk wrote:

> Are you sure about this? Normally ARM systems have flash memory (or
> some other ROM) mapped at 0, because this is where execution starts
> out of reset.

Yes I am. On this system (at least as it is now) U-boot is executed from
memory when DDR has already been initialized. So yes, I confirm DDR is
mapped from 0x00000000 to 0x3fffffff but I only have 64MB so the end of
physical RAM is 0x03ffffff.

>> First problem: I can compile U-boot with ELDK 4.1 but if I enter the
>> "examples" directory and issue a make:
> 
> Who says you should do that? The examples are automatically built when
> running "make all" (or just "make") in the top level directory.

Sorry my fault.


>> I do not have RAM at that location! Shall I modify the Makefile for this?
> 
> Yes, you have to adjust the link address to your actual memory map.

Well now it is somewhat clearer and I think I understand. I will do some
experiments on the target on Tuesday, after labor's day of course :)


> It's not only gly, but also error-prone. You should not use plain
> pointer accesses to read or write to registers, but the correct
> accessor functions/macros ({in,out}[bwl]).

Uh... are those defined for U-boot as well? Thanks.


bye!
as