This doc explains how to run kelvin SW in its Instruction Set Simulator (ISS).
Kelvin Sim is the ISS simulator that's built based on MPACT_Sim and supports all the kelvin instructions. It is used for single-core testing and debugging.
Running the Kelvin SW binary (ELF or the rendered .bin file) can be done with the following CLIs
source build/setup.sh m kelvin_sim sim_kelvin <elf/bin file path>
The bash function detects the file type by ELF's magic_bytes and launches the kelvin_sim. kelvin_sim runs the executable, and depends on the terminator ops mpause or ebreak, it prints out different messages before exit the simulator.
Illegal instruction also terminates the simulation, with the fault PC printed out.
sim_kelvin <elf file path> debug
It launches kelvin_sim in the interactive mode. It acts as a debugger, with break, run, and step available for instructions. Use help to see the supported debug functions.
Kelvin simulator can connect to renode and then be integrated with the full nexus behavioral simulation framework. As the first step, It uses a rv32im placeholder model running non-SIMD binaries so we can test the integrated system behaviors
NOTE: Running vector-op program in renode is not supported yet.
Running the Kelvin SW binary can be done with the following CLIs
source build/setup.sh m renode sim_kelvin_renode <location of the kelvin SW .bin file>
The .bin file is the binary blob of the loadable segment parsed by cache/toolchain_kelvin/bin/riscv32-unknown-elf-objcopy. It is the additional output from the Kelvin build rules from either the Bazel build or CMake build after the .elf executables are built
Like Cantrip debugging, Kelvin Renode ISS can also attached to GDB to debug the SW, step through the program, and dump the register or memory content.
At the first shell session, run
source build/setup.sh sim_kelvin_renode <.bin file> debug
At the second shell session, run GDB as
cache/toolchain/bin/riscv32-unknown-elf-gdb -ex "target remote: 3333" <elf path>
Notice we load the actual .elf executable here so we can get the symbols and proper address. After the Renode GDBServer is attached to GDB, GDB will automatically start the Renode simulation (without actually running the program)
Set up the proper breakpoints on the GDB console then continue the execution, e.g.,
b main continue
Note: Once GDB is attached to the Renode simuation, you can start stepping the execution without run or set up the breakpoint at the entry of the executable. In fact, the first breakpoint can be captured reliably if it is after the entry address.