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==IntroductionAsymmetric Multiprocessing (AMP) with OpenAMP==As known, the STM32MP115x SoC is powered by a heterogeneous architecture comprising a single/dual ARM Cortex-A7 (CA7) and an ARM Cortex-M4 (CM4). When the application requires implementing an [https://en.wikipedia.org/wiki/Asymmetric_multiprocessing Asymmetric Multiprocessing configuration (AMP)], the most common scenario is to use Linux on the CA7, and bare metal or RTOS-based firmware on the CM4. In either case, the [https://www.openampproject.org/ OpenAMP framework] is typically used to establish a [https://wiki.st.com/stm32mpu/wiki/Coprocessor_management_overview communication channel between the cores]. The [[DESK-MP1-L/Development/Building the Yocto BSP|Yocto build system]] at the heart of the DESK-MP1-L provides some examples based on this framework OpenAMP to demonstrate how to set up AMP configurations. The following section illustrates one of them, namely <code>OpenAMP_TTY_echo</code>. This example is built when Yocto is run to generate the Linux root file system for the target. For more details, please see the [https://www.st.com/en/embedded-software/stm32cubemp1.html STM32CubeMP1 firmware] documentation and the associated [https://github.com/STMicroelectronics/STM32CubeMP1/tree/1.6.0/Projects/STM32MP157C-DK2/Applications/OpenAMP/OpenAMP_TTY_echo source code].===Running the OpenAMP_TTY_echo example===The example is automatically built by Yocto. To run it, please issue the following commands on the target's Linux console:

</pre>It is worth remembering that it is also possible to start the CM4 firmware before the Linux kernel is started.