How to configure uniprocessor mode

Applicable for

STM32MP15x lines

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1 Purpose

This article explains how to switch from a SMP (symmetric multiprocessing) Linux^® kernel configuration to a UP (uniprocessor) Linux kernel configuration.

2 Rationale

Considering that STMicroelectronics Linux kernel is configured in SMP mode by default, single Arm Cortex-A core users may wish to disable this configuration in order to avoid trying to start the second core at every boot. Please note that keeping the SMP mode enabled on a single processor does not have any performance impact on the kernel in most use cases, so this change is not mandatory.

3 Modify kernel configuration

To switch to UP configuration, disable SMP configuration. To do that, search SMP in kernel menuconfig and disable the option.