[U-Boot-Users] Debugging u-boot with BDI2000
Wolfgang Denk
wd at denx.de
Fri Jul 18 21:08:49 CEST 2003
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
--
Software Engineering: Embedded and Realtime Systems, Embedded Linux
Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Email: wd at denx.de
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