[U-Boot-Users] standalone code
Wolfgang Denk
wd at denx.de
Thu Aug 14 20:48:07 CEST 2003
Dear Philippe,
in message <007601c3626c$9e7d2ee0$10c8c8c8 at philippesimal> you wrote:
>
> In the meanwhile I'm writing some hardware debug code that does not use
> any kernel.
It wouldbe great if you contributed such code as part of the post/
stuff.
> (1)First I tried to run it as a standalone program just like the 'hello
> world' example. The problem is that I do not have access to the drivers
> used by u-boot. I only can use some system calls like mon_printf()...
Please update your U-Boot sources. We reworked the standalone
applications code, so it now not only works on all architectures, but
also allows for easy extension. See doc/README.standalone for
details.
> So I tried to link my debug code directly to the u-boot code with an
> entry point just before the call main_loop() in board.c.
> This works fine except that I cannot use function pointers used in my
> debug menu .
You can, but you have to manually relocated them, or use dynamic
initialization.
> (2)I know this has something to do with the code relocation from flash
> to sdram so I tried to relocate all my pointers. Ok that didn't work.
It is trivial to fix. See how all the other static pointers get
relocated (basicly, just add gd->reloc_off).
> So my questions are, (1) is it possible to make a standalone pease of
> software that runs in sdram with the full use of the u-boot drivers?
Yes, easily.
> (2) What must I do to use my pointers whitout crashing the ppc.
See above.
Hope this helps.
Best regards,
Wolfgang Denk
--
Software Engineering: Embedded and Realtime Systems, Embedded Linux
Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Email: wd at denx.de
"Obviously, a major malfunction has occurred."
-- Steve Nesbitt, voice of Mission Control, January 28,
1986, as the shuttle Challenger exploded within view
of the grandstands.
More information about the U-Boot
mailing list