Running SMP FreeRTOS application on A53

Table of Contents

• Introduction
• Running SMP application using CCS
  • Loading and running a .out file for an SMP application
  • Building and running an SMP application using CCS
• Dhrystone benchmark values for SMP FreeRTOS on A53
• See also

Introduction

Note

Only example application that supports SMP mode can be run on the four A53 cores in SMP mode.

Attention

All SPI interrupts are routed to A53 Core 0.

SMP FreeRTOS kernel support is added in the DPL layer for A53 core. This makes use of all the four A53 cores for running applications by using the FreeRTOS SMP kernel for scheduling tasks on all the four cores.

SMP application uses SGI interrupt interrupt number 0 for communication between A53 cores. So care must be taken not to use this interrupt in user applications.

SMP applications can be loaded via SBL as well as CCS. A53 cores must be run as sync group in CCS when running SMP applications.

Running SMP application using CCS

Note

Only example application that supports SMP mode can be run on the four A53 cores in SMP mode.

Loading and running a .out file for an SMP application

When runnig SMP application using CCS, the cores needs to be run as sync group.

A sync group can be created as follows. This ensures the same binary is executed on all the four cores from the same entry point.

Sync group creation in CCS

Connect the Target Group

Connect CPUs

CCS Debug session after Syncgroup is connected

Building and running an SMP application using CCS

An SMP example for A53 can be imported and build just as a single core A53 application. But all the four a53 cores must be selected and sync group must be created when launching the debug session.

Launching SMP debug session in CCS

Connect to target and load the .out file then run

CCS Debug session after load

Dhrystone benchmark values for SMP FreeRTOS on A53

Note

The values obtained is from example - Dhrystone benchmarking demo when build in release mode

The dhrystone values can be used to compare the performance between single core FreeRTOS on A53 and SMP FreeRTOS on A53.

No of Threads	No of Iterations	Dhrystone per second for Single Core FreeRTOS on A53	Dhrystone per second for SMP FreeRTOS on A53
1	30000000	7602697.5	7692834.5
2	30000000	7623452.5	15385641.0
5	30000000	7652666.5	19074966.0
10	30000000	7656853.0	25470718.0

See also

For more details on debugging an SMP application using CCS, see here