CoreMark¶

CoreMark is a CPU benchmark provided by EEMBC. apps/coremark/ uses CMake FetchContent to automatically fetch the upstream source and builds with no custom source files — only a CMakeLists.txt.

Prerequisites¶

aarch64 cross-compiler extracted in toolchain/
Host OS: x86_64 Linux
CMake 3.16 or later
Internet connection (only for the initial FetchContent download)

Design¶

Why the posix/ port¶

The upstream CoreMark posix/ port operates with the following settings:

USE_CLOCK=0, HAS_TIME_H=1 → uses clock_gettime(CLOCK_REALTIME) for timing
SEED_METHOD=SEED_ARG → seed configurable via command-line arguments (auto-detect when no arguments)
MEM_METHOD=MEM_MALLOC → standard heap allocation

This works out of the box on the Coral Dev Board's Mendel Linux (Debian-based / glibc).

Why no custom source files are needed¶

CORETIMETYPE is only used within core_portme.c (core_main.c uses CORE_TICKS=clock_t)
The posix port's core_portme.c works as-is
Configuration differences (ITERATIONS, etc.) can be handled via runtime arguments or CMake -D
Only FLAGS_STR needs to be defined from CMake (upstream Makefile also passes it via -D)

-O2 optimization¶

-O2 is explicitly specified to produce meaningful benchmark results. It is also reflected in FLAGS_STR, which appears in the CoreMark report output as the compiler flags used.

CMakeLists.txt¶

apps/coremark/CMakeLists.txt:

cmake_minimum_required(VERSION 3.16)
project(coremark C)

# --- Fetch upstream CoreMark source ---
include(FetchContent)
FetchContent_Declare(
    coremark_src
    GIT_REPOSITORY https://github.com/eembc/coremark.git
    GIT_TAG        main
    GIT_SHALLOW    TRUE
)
FetchContent_GetProperties(coremark_src)
if(NOT coremark_src_POPULATED)
    FetchContent_Populate(coremark_src)
endif()

# --- Build the CoreMark benchmark ---
add_executable(coremark
    ${coremark_src_SOURCE_DIR}/core_list_join.c
    ${coremark_src_SOURCE_DIR}/core_main.c
    ${coremark_src_SOURCE_DIR}/core_matrix.c
    ${coremark_src_SOURCE_DIR}/core_state.c
    ${coremark_src_SOURCE_DIR}/core_util.c
    ${coremark_src_SOURCE_DIR}/posix/core_portme.c
)

target_include_directories(coremark PRIVATE
    ${coremark_src_SOURCE_DIR}
    ${coremark_src_SOURCE_DIR}/posix
)

# Benchmark-meaningful optimization
target_compile_options(coremark PRIVATE -O2)

# Suppress -Werror from toolchain for upstream code
target_compile_options(coremark PRIVATE -Wno-error)

# FLAGS_STR: required by posix/core_portme.h for benchmark report output
target_compile_definitions(coremark PRIVATE "FLAGS_STR=\"-O2\"")

# Deploy / Run
include(${CMAKE_CURRENT_LIST_DIR}/../../cmake/coral-deploy.cmake)

coral_add_deploy_target(
    DEPLOY_DIR /home/mendel/work/coremark
    DEPENDS coremark
    FILES "$<TARGET_FILE:coremark>:coremark"
)

coral_add_run_target(
    COMMAND /home/mendel/work/coremark/coremark
)

FetchContent automatically downloads the CoreMark source at build time, so no manual source placement is needed. It builds the 5 core files plus posix/core_portme.c from the sources extracted into coremark_src_SOURCE_DIR.

Build¶

Run from the repository root directory.

cmake -B build/coremark -S apps/coremark \
    -DCMAKE_TOOLCHAIN_FILE=$(pwd)/cmake/toolchain-coral-aarch64.cmake
cmake --build build/coremark

Verify the generated ELF¶

file build/coremark/coremark

Expected output:

coremark: ELF 64-bit LSB executable, ARM aarch64, version 1 (SYSV), dynamically linked, ...

Deploy and Run¶

The CMake deploy / run targets handle transfer and execution in one command:

cmake --build build/coremark --target deploy
cmake --build build/coremark --target run

Example output:

2K performance run parameters for coremark.
CoreMark Size    : 666
Total ticks      : 12187
Total time (secs): 12.187000
Iterations/Sec   : 4923.278904
Iterations       : 60000
Compiler version : GCC8.3.0
Compiler flags   : -O2
Memory location  : Please put data memory location here
        (e.g. code in flash, data on heap etc)
seedcrc          : 0xe9f5
[0]crclist       : 0xe714
[0]crcmatrix     : 0x1fd7
[0]crcstate      : 0x8e3a
[0]crcfinal      : 0xbd59
Correct operation validated. See README.md for run and reporting rules.
CoreMark 1.0 : 4923.278904 / GCC8.3.0 -O2 / Heap

Runtime Options¶

CoreMark runs with default settings (auto-detect ITERATIONS, auto-select SEED) when executed without arguments.

coremark <seed1> <seed2> <seed3> <iterations>

Argument	Description	Default
seed1, seed2, seed3	Benchmark input seeds	Auto-selected (validation/performance/profile)
iterations	Number of iterations	Auto (minimum value for ~10 seconds execution)

Example: run with 50000 iterations:

scripts/run.sh '/home/mendel/work/coremark/coremark 0 0 0x66 50000'

CMake Targets¶

Configuration¶

cmake -B build/coremark -S apps/coremark \
    -DCMAKE_TOOLCHAIN_FILE=$(pwd)/cmake/toolchain-coral-aarch64.cmake

Target List¶

Target	Command	Description
(default)	`cmake --build build/coremark`	Build C binary
`deploy`	`cmake --build build/coremark --target deploy`	Build + transfer to board
`run`	`cmake --build build/coremark --target run`	Run remotely on board

Connection Settings¶

Customize connection parameters via CMake cache variables:

Variable	Default	Description
`CORAL_IP`	(empty = auto-detect via mdt)	Coral Dev Board IP address

Future Extensions¶

Multi-threaded support¶

To run CoreMark in multi-threaded mode:

Copy the upstream posix/core_portme.c to apps/coremark/src/core_portme.c
Change the source path in CMakeLists.txt to src/core_portme.c
Add -DMULTITHREAD=4 -DUSE_PTHREAD=1 in CMake and add pthread to target_link_libraries