Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

ID 814346
Date 4/01/2024
Public
Document Table of Contents

7.2.9. Boot Mode

The clock manager provides a glitch-free mechanism to switch all clocks to a low frequency boot clock under both hardware and software control. Hardware control is used in conjunction with the reset manager to provide a low frequency clock after reset assertion and during the boot process. Software control allows you to set all system clocks to a known good source before switching the clock source or modifying the PLL configuration.

The clock manager arbitrates between hardware and software boot mode requests and ensures hardware requests are taken even if a software request is in progress.