[U-Boot] "b reset" does not work in u-boot_v2010.12-rc3 with eldk4.2

Wolfgang Denk wd at denx.de
Sat Jan 8 12:41:30 CET 2011


Dear "MrGates",

please always keep the mailing list on cc:

In message <D9D3B66C8A5547E0BA21713B70C8E8A8 at Microsoft> you wrote:
> >> These indicate that in start.S,first instruction:b reset not jump success
> > 
> > What do you mean by that statement?
>     I am sorry that i have no clear.
>     I mean that "b reset"statement does not jump to the lable reset at line 104 of start.S correctly.

If you want to execute machine instructions one by one you should use
"stepi" instead of "step".

> >> The process just go from one instruction to the next.
> > 
> > You are running series of "step" commands - you are asking the
> > debugger to "go from one instruction to the next", and this is what it
> > does.  What else would you expect?
>     Maybe i misunderstand the use of "step" command of arm-linux-gdb.
>     I want gdb to simulate the execution sequence of my u-boot.

gdb does not simulate, it actually runs the code. And the "step"
command runs the code until it reaches a new source line.

If you want to step on machine instruction level you should use
"stepi" instead.

You may also want to read the documentation, for example this section
of the DULG: http://www.denx.de/wiki/view/DULG/DebuggingTricks

> >> What may be the problem?any suggestions is appreciate.
> > 
> > Where exactly do you see a problem?
>     compile success.But when i burn u-boot.bin into my NOR flash(sst39vf3201).Nothing happened.
>     So i would like to use arm-linux-gdb(eldk-4.2) with simulating.

Debugging is indeed a good idea in such a situation.  Note that gdb
does not "simulate". You will need a JTAG adapter to debug on the
real hardware.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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