mini-gdbstub-ck804

mini-gdbstub-ck804 is an implementation of the GDB Remote Serial Protocol that gives your emulators debugging capabilities.

For the user whose cpu is csky ck804, the code can be debugged without the real debugger (CK LINK). There's a catch, of course, which is that you need to export the current stack register and the memory region, which I call ramdump.

Usage

First, launch mini-gdbstub-ck804 with gdbstub_ck804 <elf_file> <ramdump_file> [port], for example:

./gdbstub_ck804 ./project.elf ./project.ramdump 6688

Second, run the gdb program, for example:

csky-elfabiv2-gdb ./project.elf

Third, connect the gdb stub, for example:

target remote :6688

If the connection fails, it's probably due to a firewall, so close or add the rule.

When the connection is successful, you can debug normally, you can use such as bt, p, set $pc, etc.

At present, only the functions related to register reading and writing and memory reading are implemented, and other functions are not supported.

This is actually very similar to gdb+corefile. For example, part of the csky cpu toolchain is not open source, and the corefile format is not known, so the gdb stub method is more general and not limited to the corefile issue.

Compile

This project supports linux and windows use, compile command:

make

After successful compilation, the executable will be in the build directory.

The core of gdbstub is mini-gdbstub. Currently, it also provides the function of generating lib:

make lib

For debugging and learning, log information can be added to compile:

make debug

Tip: On windows, you can use cygwin or mingw to compile.

Reference

Project

RinHizakura/mini-gdbstub

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