There is an easy way to debug TF-M when using VScode, not DS5. It can be implemented in Ubuntu/MacOS(M silicon) environments.

Download

Some key dependencies:

# install mac gnuarm: click the package to install
wget https://developer.arm.com/-/media/Files/downloads/gnu-rm/10.3-2021.10/gcc-arm-none-eabi-10.3-2021.10-mac.pkg?rev=b382d51ec8d34c3fa421cf57ce97f146&hash=E3B897C8DA0E3E56C151F397C004104F00AE2EB8
# export PATH='/Applications/ARM/bin':${PATH}
 
# install qemu
brew install qemu # MacOS
sudo apt-get install qemu-system # Ubuntu

Build and run qemu

Set commands in .zshrc:

WORK_PATH=<your own tfm opath>
CMAKE_BUILD_PATH="$WORK_PATH/cmake_build"
 
alias run-qemu-an521="qemu-system-arm -cpu cortex-m33 \
                        -machine mps2-an521 \
                        -nographic -m 16 -vga none -net none \
                        -chardev stdio,id=con,mux=on \
                        -serial chardev:con \
                        -mon chardev=con,mode=readline \
                        -icount shift=6,align=off,sleep=off \
                        -rtc clock=vm -chardev pty,id=hostS0 \
                        -serial chardev:hostS0 \
                        -kernel $CMAKE_BUILD_PATH/bin/bl2.elf \
                        -device loader,file=$CMAKE_BUILD_PATH/bin/tfm_s_ns_signed.bin,addr=0x10080000"
 
alias debug-qemu-an521="qemu-system-arm -cpu cortex-m33 \
                        -machine mps2-an521 \
                        -nographic -m 16 -vga none -net none \
                        -chardev stdio,id=con,mux=on \
                        -serial chardev:con \
                        -mon chardev=con,mode=readline \
                        -icount shift=6,align=off,sleep=off \
                        -rtc clock=vm -chardev pty,id=hostS0 \
                        -serial chardev:hostS0 \
                        -kernel $CMAKE_BUILD_PATH/bin/bl2.elf \
                        -device loader,file=$CMAKE_BUILD_PATH/bin/tfm_s_ns_signed.bin,addr=0x10080000 \
                        -s -S" # -s, tcp gdbsever, localhost:1234; -S, listen the gdb

Note: CMAKE_BUILD_TYPE shall be Debug.
Run run-qemu-an521 to get the build log.

Debug

1. Install the extension Cortex Debug in VScode.

2. Set launch.json file, in the left debug extension, you can see ‘create a new launch.json file’, then choose ‘Cortex Debug’. Copy the below JSON configs to override it.

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Cortex Debug",
            "request": "launch",
            "type": "cortex-debug",
            "runToEntryPoint": "main",
            "cwd": "${workspaceFolder}",
            "servertype": "external",                                      // Debug from server, loaclhost 1234
            "gdbPath": "/Applications/ARM/bin/arm-none-eabi-gdb",          // Path of gdb
            "gdbTarget": "localhost:1234",
            "showDevDebugOutput": "raw",
            "symbolFiles": [
                {
                    "file": "${workspaceFolder}/cmake_build/bin/tfm_ns.elf",
                },
            ]
        }
    ]
}

3. Run debug-qemu-an521 to start the kernel.

4. Start debugging. Click the start button in debug extension.

   1. Set the breakpoint to the left of the code line, anywhere of any file in the editor.
   2. Click continue to run to the breakpoint.
   3. Right-click the code and find Open Disassembly View. Then you can see the asm code and PC. You can also set a breakpoint in asm file.
   4. Open the terminal and switch to the Memory window to see the RAM.
   5. The local, global variables and registers are shown in VARIABLES in debug extensions. Click 0x to show hex format data.
   6. CALL STACK shows the calling routine of functions.