The OpenSTLinux BSP encompasses the following components:
- The boot chain based on TF-A and U-Boot
- The OP-TEE secure OS running on the Cortex-A in secure mode
- The Linux kernel running on the Cortex-A in non-secure mode
The figure below is clickable so that the user can directly jump to one of the sub-levels listed above.
![](/stm32mpu/nsfr_img_auth.php/d/d3/OpenSTLinux_BSP_SW_Overview.png)
OpenSTLinux BSP architecture overview