[U-Boot-Users] hello world application

[Wolfgang Denk]

In message <20041031080457.27425.qmail at web12009.mail.yahoo.com> you wrote:
> I want to make gzipped hello_world application and
> later execute it using bootm command.

Please  use  correct  terms.  The  "hello_world"  is  so  small  that
compressing it makes no sense. Maybe you are talking about some other
standalone application, which is bigger?

> I figured that mkimage is the utility for making
> compressed STANDALONE image.
> 
> But it needs an option mkimage -d <datafile>
> 
> Now what is this datafile? Is it hello_world or
> hello_world.bin or hello_world.srec

It is none of them. You mentioned that you want to build a compressed
image, so you must compress the fiule first, and none of  hello_world
nor  hello_world.bin  nor  hello_world.srec  is compressed. Also, ask
yoruself  if  the  processor  will  be  able   to   find   executable
instructions in a S-Record file, or in a ELF header. it will not.

You  should  run  gzip  on  hello_world.bin  and  use  the  resulting
compressed binary image as input.

> I tried all 3, but they give different sizes of
> gzipped image. So i am confused.

I would be confused if it was different. Since mkimage always adds  a
64  byte  header, the resulting file sizes MUST be different when you
use files with different sizes as input.


Best regards,

Wolfgang Denk

-- 
See us @ Embedded/Electronica Munich, Nov 09 - 12, Hall A.6 Booth 513
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
While most peoples' opinions change, the conviction of their correct-
ness never does.