2024 Current State by crt0

Writing/Reading variables, memory, registers (only as 32bit), call stack - works.

Example usage: run sample with ps2link: ps2client -h 192.168.1.13 execee host:testgdb.elf in nanother terminal mips64r5900el-ps2-elf-gdb -x ps2.sh

TODO: rewrite metwork stack

INTRODUCTION

ps2gdbStub is a tcp stub for the gnu debugger. It could be easily changed to not use tcp. The low level portion reads 128 bits for the 32 gprs and also for lo and hi, although these are converted down to 32 bits before sending to the remote GDB.

Currently, the code must be uploaded via pukklink or ps2link. Naplink won't do it!

As for building the remote GDB, I configured gdb as mips-idt-elf and hacked about with it a bit. I managed to get the latest weekly snapshot (which at time of writing was gdb+dejagnu-20030801.tar.bz2) to work, after some hacking around. I've included a .cmd file for use with the remote GDB. You'll need to change the target line with the correct IP of your ps2. To invoke, from the shell, type <gdb -x ps2.cmd>

With reference to the frame pointer, gpr $30 should be the frame pointer, this is what the MIPS abi says anyway. However, our toolchain appears to use grp $30 as another saved register (s8), so I just report the fp to be the same as the sp at the moment.

COPYRIGHT FOR PS2GDBSTUB

Copyright (c) 2003 Ray Donnelly (rdonnelly@polygoons.com) All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
2. The author grants you a license to use ps2gdbStub for academic, research and non-commercial purposes only.
3. The author imposes no restriction on any code developed using the software. However, the author retains a non-exclusive royalty-free license to any modification to the distribution made by the licensee.

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   • Integration of all or part of the source code into a product for sale or commercial license by or on behalf Licensee to third parties, or
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