We’re pleased to announce OpenSTLinux 6.1, now with M33-TD support, enabling you to leverage the Cortex®-M33 core as a trusted domain (TD) boot processor.
This release provides a unified ecosystem and contributes to the 5-year maintenance commitment for all STM32 MPUs in production, ensuring your products are built on a stable, long-term software foundation.
What’s new?
1) Offload early boot processes to Cortex®-M33
- Reduce startup load on Cortex®-A35 cores by delegating initial boot processes and security checks to the Cortex®-M33
- Enables faster, more efficient boot sequences and lower power consumption
2) Improved boot time & system efficiency
- Boot critical early tasks on Cortex-M33 before going on with Cortex®-A35 start up
- Optimizes overall system startup time and resource usage
3) Enhanced security through isolation
- Keep secure services on the Cortex-M33 isolated trusted domain
- This isolation strengthens the protection of secure boot applications against attacks
4) Independent Cortex®-A35 reboot & low-power modes
- Supports independent reboot of the Cortex®-A35 cores without impacting the Cortex®-M33, providing flexibility for the application and safety foundations for the services running on the Corte-M33
- Various low-power modes are now enabled, leveraging the new M33-TD architecture for improved power usage and longer battery life
Why this matters to you
- Optimize your system boot by launching early services and trusted boot tasks on Cortex®-M33
- Increase security by isolating critical secure boot functions on a dedicated core
- Optimize power consumption by leveraging low-power modes and offloading tasks
- Test and prototype easily on supported STM32MP257 evaluation board and discovery kits with flexible boot options, selected via the onboard boot pins
What is included in this release for M33-TD?
- Support for STM32MP25-EVAL and STM32MP21-DK boards
- Dual-device boot: sNOR (M33) followed by SDCard or eMMC (A35)
- Single-device boot: SDCard, eMMC, or sNOR
- M33 protected storage on NOR device
- OTP management via TF-M Key Store PSA service
- Independent reboot of Cortex®-A35 cores
- Low-power modes (Run1, Run2)
- Optimized boot time: the M33-TD flavor enables early service launch on Cortex®-M, ensuring fast system availability within a controlled power budget
- M33 non-secure early splash screen support on external low-resolution I2C panel
OpenSTLinux 6.1 empowers you to build faster, more secure, and reliable embedded systems with confidence. Download the latest version here: STM32 MPU OpenSTLinux Distribution.
Additional resources
First published on Jul 16, 2025
