Re: Remote Debugging on IXDP425

Peter Reilley
2003-12-03T22:24:21Z

----- Original Message -----
From: "Daniel Jacobowitz" <drow@mvista.com>
To: "Stephen A. Witt" <sawitt@electra.rsc.raytheon.com>
Cc: <gdb@sources.redhat.com>
Sent: Wednesday, December 03, 2003 4:29 PM
Subject: Re: Remote Debugging on IXDP425

> On Wed, Dec 03, 2003 at 11:17:18AM -0800, Stephen A. Witt wrote:
> > Thanks very much for the response, very dumb mistake on my part. I had
> > built a gdb with an arm-linux target, but I inadvertantly used the
normal
> > i386 gdb when I first tried this. Using the arm-linux gdb that I had
> > built, with the information you provided, I found that the breakpoint
> > instruction being sent was 0x01009fef. The correct bp inst for an IXP425
> > (a big-endian CPU) is 0xef9f0001. So I modified the breakpoint
instruction
> > value in gdb to 0xef9f0001 and breakpoints work now.
>
> This is a GDB bug fixed in more recent versions of GDB.
>
> > There are some other problems, like when I do 'step' or 'next' I get a
> > "ptrace: bogus breakpoint trap". Floating point variable display doesn't
> > work. So I'm looking into these.
>
> The former is a Linux kernel bug. I sent Russell an explanation of the
> problem and got no response. Just turn off the message.
>
> > I just hacked in the changed breakpoint instruction value but it seems
the
> > correct way to do it would be to tell gdb during configuration that the
> > target is an xscale CPU, and conditionally compile in the correct value.
> > At first I thought I hadn't built gdb properly, but it doesn't appear
that
> > gdb-6.0 really supports an IXP425. Is this true?
>
> ARM/Linux in big endian mode is definitely still a black sheep. None
> of the GNU tools really support it out of the box, only various
> vendors' tools.
>
> --
> Daniel Jacobowitz
> MontaVista Software Debian GNU/Linux Developer
>

I have run a Sharp Arm 7 in both big and little endian modes. This
is running on a bare system with no OS. I did this as part of my work on
the
binary packages that are provided on the Macraigor web site;

www.macraigor.com

The RPM package contains examples for both big and little endian mode.

Pete.