Kgdb on Motorola 8451 ppc board

Swarthout Ed-RA8734 Ed.Swarthout at
Tue Jul 6 14:39:02 EST 2004

Tameen asked:

> Any pointers to where I can get info to get kgdb working for this cross
> arch debugging will be helpful..

Three things to look at:

1. You can tell gdb to show everything going over the serial port with:

(gdb) set debug remote 1

but I get similar messages when nothing is even attached to the serial port.

2. Are you seeing "kgdb init" in the console logs?
That message should come from kgdb_map_scc() in gen550_kgdb.c
What serial port are you using for kgdb?

3. Is the gdb stub actually in a position to do a serial port read?  It will only be listening as a result of a trap or if "gdb" is passed on the kernel cmdline.  (See setup_arch() in setup.c)

Disclaimer: I haven't actually tried kgdb on this board and I'm on vacation for two weeks...

Ed dot Swarthout at Freescale dot com

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