[U-Boot-Users] Debugging u-boot with BDI2000

[Wolfgang Denk]

Dear Jürgen,

in message <200307181428.20714.jbeisert at eurodsn.de> you wrote:
>
> I did use hardware breakpoints.

OK.

> > > Perhaps my english is very bad. Question was: Why the cpu is running
> > > normal with "reset run", and did not run, when I enter "reset halt",
> > > enter a breakpoint and than "go" (it never reaches the breakpoint).
> >
> > Which address is PC pointing to when you enter "go"?
> 
> 0x700. It wants to handle an exeption (but at this point, there is no code 
> present). So it hangs forever.

It will do you little good to try "go" when PC points to 0x700.

> > Why don't you use plain "reset" ? [Did you try it?]
> 
> My u-boot implementation hangs at a very late position. So I have to place a 

Sorry, but this statement makes no sense.

After a "reset", the BDI is expected to stop the  CPU  right  at  the
reset entry point, i. e. PC should point to 0xFFFFFFFC or so.

Not a single instruction of U-Boot code should be  executed  after  a
reset.

> But with "reset run" the breakpoint is lost....And with "reset halt", setting 
> a breakpoint and "go" it hangs after a few instructions...Aaargh.

Let me repeat my question:

Why don't you use plain "reset" ? [Did you try it?]

Did you make sure thet the CPUi s stopped when you attempt to set the
breakpoint? (issue a "halt" command before setting the BP).


Best regards,

Wolfgang Denk

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