TF-M IPC

Overview

This is a simple TF-M integration example that can be used with an ARMv8-M supported board.

It uses IPC Mode for communication, where TF-M API calls are made to the secure image via an IPC mechanism, as opposed to Library Mode, where the IPC mechanism is bypassed in favor of direct calls.

Zephyr uses Trusted Firmware (TF-M) Platform Security Architecture (PSA) APIs to run this sample in a secure configuration, with Zephyr itself running in a non-secure configuration.

The sample prints test info to the console either as a single-thread or multi-thread application.

The sample reboots after 5 seconds to demonstrate rebooting with TF-M. The sys_reboot call is routed to TF-M, since the nonsecure app is not allowed to perform the reboot directly.

Building and Running

This project outputs test status and info to the console. It can be built and executed on MPS2+ AN521 and ST Nucleo L552ZE Q.

On MPS2+ AN521:

Build Zephyr with a non-secure configuration (-DBOARD=mps2/an521/cpu0/ns).

cd $ZEPHYR_ROOT/samples/tfm_integration/tfm_ipc/
mkdir build
cd build
cmake -DBOARD=mps2/an521/cpu0/ns ..
make

You can also use west as follows:

$ west build -p -b mps2/an521/cpu0/ns zephyr/samples/tfm_integration/tfm_ipc

Copy application binary files (mcuboot.bin and tfm_sign.bin) to <MPS2 device name>/SOFTWARE/.

Open <MPS2 device name>/MB/HBI0263C/AN521/images.txt. Edit the AN521/images.txt file as follows:

TITLE: Versatile Express Images Configuration File

[IMAGES]
TOTALIMAGES: 2 ;Number of Images (Max: 32)

IMAGE0ADDRESS: 0x10000000
IMAGE0FILE: \SOFTWARE\mcuboot.bin  ; BL2 bootloader

IMAGE1ADDRESS: 0x10080000
IMAGE1FILE: \SOFTWARE\tfm_sign.bin ; TF-M with application binary blob

Reset MPS2+ board.

If you get the following error when running cmake:

CMake Error at cmake/Common/FindGNUARM.cmake:121 (message):
arm-none-eabi-gcc can not be found.  Either put arm-none-eabi-gcc on the
PATH or set GNUARM_PATH properly.

You may need to edit the CMakeLists.txt file in the tfm_ipc project folder to update the -DGNUARM_PATH=/opt/toolchain/arm-none-eabi path.

On QEMU:

The MPS2+ AN521 target (mps2/an521/cpu0/ns), which is based on a dual core ARM Cortex-M33 setup, also allows you to run TF-M tests using QEMU if you don’t have access to a supported ARMv8-M development board.

As part of the normal build process above, a binary is also produced that can be run via qemu-system-arm. The binary can be executed as follows:

qemu-system-arm -M mps2-an521 -device loader,file=build/zephyr/tfm_merged.hex -serial stdio

You can also run the binary as part of the west build process by appending the -t run flag to the end of your build command, or in the case of ninja or make, adding the run commands:

$ west build -b mps2/an521/cpu0/ns zephyr/samples/tfm_integration/tfm_ipc -t run

Or, post build:

$ ninja run

On ST Nucleo L552ZE Q or STM32L562E-DK Discovery:

This sample was tested on Ubuntu 18.04 with Zephyr SDK 0.11.3.

Build Zephyr with a non-secure configuration:

Example, for building non-secure configuration for Nucleo L552ZE Q
$ west build -b nucleo_l552ze_q/stm32l552xx/ns samples/tfm_integration/tfm_ipc/
Example, for building non-secure configuration for STM32L562E-DK Discovery
$ west build -b stm32l562e_dk/stm32l562xx/ns samples/tfm_integration/tfm_ipc/

The script to initialize the device is available in the build/tfm folder:

regression.sh: Sets platform option bytes config and erase platform.

Run them in the following order to flash the board:

$ ./build/tfm/api_ns/regression.sh
$ west flash
Note

Note that arm-none-eabi-gcc should be available in the PATH variable and that STM32_Programmer_CLI is required to run regression.sh (see https://www.st.com/en/development-tools/stm32cubeprog.html). If you are still having trouble running these scripts, check the Programming and Debugging section of the Nucleo L552ZE Q or STM32L562E-DK Discovery documentation.

On LPCxpresso55S69:

Build Zephyr with a non-secure configuration:

$ west build -p -b lpcxpresso55s69_ns samples/tfm_integration/tfm_ipc/ --

Make sure your board is set up with LPC-Link2 J-Link Onboard Debug Probe, since this isn’t the debug interface boards ship with from the factory;

Next we need to manually flash the resulting image (tfm_merged.bin) with a J-Link as follows:

JLinkExe -device lpc55s69 -if swd -speed 2000 -autoconnect 1
J-Link>r
J-Link>erase
J-Link>loadfile build/zephyr/tfm_merged.bin

Resetting the board and erasing it will unlock the board, this is useful in case it’s in an unknown state and can’t be flashed.

We need to reset the board manually after flashing the image to run this code.

On nRF5340 and nRF9160:

Build Zephyr with a non-secure configuration (-DBOARD=nrf5340dk/nrf5340/cpuapp/ns or -DBOARD=nrf9160dk/nrf9160/ns).

Example, for nRF9160, using cmake and ninja

cd <ZEPHYR_ROOT>/samples/tfm_integration/tfm_ipc/
rm -rf build
mkdir build && cd build
cmake -GNinja -DBOARD=nrf9160dk/nrf9160/ns ..

If building with BL2 (MCUboot bootloader) enabled, manually flash the MCUboot bootloader image binary (bl2.hex).

Example, using nrfjprog on nRF9160:
nrfjprog -f NRF91 --program tfm/bin/bl2.hex --sectorerase

Finally, flash the concatenated TF-M + Zephyr binary.

Example, for nRF9160, using cmake and ninja
ninja flash

On BL5340:

Build Zephyr with a non-secure configuration (-DBOARD=bl5340_dvk/nrf5340/cpuapp/ns).

Example using cmake and ninja

cd <ZEPHYR_ROOT>/samples/tfm_integration/tfm_ipc/
rm -rf build
mkdir build && cd build
cmake -GNinja -DBOARD=bl5340_dvk/nrf5340/cpuapp/ns ..

Flash the concatenated TF-M + Zephyr binary.

Example using west

west flash --hex-file zephyr/tfm_merged.hex

Sample Output

[INF] Starting bootloader
[INF] Beginning BL2 provisioning
[WRN] TFM_DUMMY_PROVISIONING is not suitable for production! This device is NOT SECURE
[INF] Image index: 1, Swap type: none
[INF] Image index: 0, Swap type: none
[INF] Bootloader chainload address offset: 0x80000
[INF] Jumping to the first image slot
[INF] Beginning TF-M provisioning
[WRN] TFM_DUMMY_PROVISIONING is not suitable for production! This device is NOT SECURE
[WRN] This device was provisioned with dummy keys. This device is NOT SECURE
[Sec Thread] Secure image initializing!
Booting TF-M v2.0.0
Creating an empty ITS flash layout.
Creating an empty PS flash layout.
[INF][Crypto] Provisioning entropy seed... complete.
Timer with period zero, disabling
*** Booting Zephyr OS build v3.6.0 ***
TF-M IPC on (.*)
The version of the PSA Framework API is 257.
The PSA Crypto service minor version is 1.
Generating 256 bytes of random data:
[...]