[U-Boot-Users] Re: how can I boot u-boot from 0x40000 in flash instead

Wolfgang Denk wd at denx.de
Fri Jul 15 22:27:01 CEST 2005

In message <cd490d13050715112919118c13 at mail.gmail.com> you wrote:
> Thanks. I am a newbie on u-boot. 
> 1. I changed the u-boot.lds in my board directory. in the line
> .=0x00000000 I changed it to .=0x00040000

This will hardly be sufficient. Remember that U-Boot  expects  to  be
started  from  the  reset  vector,  which  it  will  also assume when
relocating, etc. Just  changing  the  address  is  not  sufficient  -
instead  you  will  have to create a "gap" where you rpoprietary boot
code fits in.

> 2. Could you please tell me where are the codes which COPY the code
> from flash to the cache and sdram?

I hope you will not continue to ask where  to  find  each  and  every
function.  You  are  supposed to have the knowledge and tools to find
your own way through the code. Tools like grep or ctags may help...

See function relocate_code() in cpu/*/start.S

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
"Where shall I begin, please your Majesty?" he asked. "Begin  at  the
beginning,"  the  King said, gravely, "and go on till you come to the
end: then stop."    - Alice's Adventures in Wonderland, Lewis Carroll

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