SPRADK8 February   2025 AM62P

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Hardware Used
    1. 2.1 AM62Px Processor
    2. 2.2 SK-LCD1
    3. 2.3 Display Subsystem on AM62P
  6. 3Early Splash-Screen Architecture
    1. 3.1 Boot Stages on AM62P
    2. 3.2 Flicker-Free Transition
  7. 4Flicker-Free Transition From SPL to U-Boot
    1. 4.1 Steps to Test
    2. 4.2 Measurements
  8. 5Flicker-Free Transition From SBL to Linux Kernel
    1. 5.1 Steps to Test
    2. 5.2 Measurements
  9. 6Results

1 Introduction

Increasing numbers of automotive, industrial, and robotic use-cases require enabling the display as early as possible in the boot cycle. The operating systems involve multiple stages for boot up and a bootloader is the first software component to come up and initialize the system before booting up to the full system. This application report explains how to enable the display at the bootloader stage, display a splash-screen or animation at this stage, and have a flicker-free transition to the system UI. The splash screen enablement is explained for U-Boot which is a widely used open-source bootloader, as well as a Secondary Bootloader (FreeRTOS®-based) which can perform a fast boot up to Linux using the Falcon mode boot flow. This guide then explains how the splash screen display context can be preserved while the system is booting up and a flicker-free transition to the system UI can be achieved.