Nios® V Embedded Processor Design Handbook

ID 726952
Date 11/25/2024
Public
Document Table of Contents

4.4.2.2. Nios® V Processor Bootloader via Secure Device Manager

The Bootloader via Secure Device Manager (SDM) is a HAL application code utilizing the Mailbox Client Intel® FPGA IP HAL driver for processor booting. Altera recommends this bootloader application when using the configuration QSPI flash in SDM-based devices to boot the Nios® V processor.

Upon system reset, the Nios® V processor first boots the Bootloader via SDM from a tiny on-chip memory and executes the Bootloader via SDM to communicate with the configuration QSPI flash using the Mailbox Client IP.

The Bootloader via SDM performs the following tasks:

  • Locates the Nios® V software in the configuration QSPI flash.
  • Copies the Nios® V software into the on-chip RAM or external RAM.
  • Switches the processor execution to the Nios® V software within the on-chip RAM or external RAM.

Once the process is complete, the Bootloader via SDM transfers program control over to the user application. Altera recommends the memory organization as outlined in Memory Organization for Bootloader via SDM.

Figure 15. Bootloader via SDM Process Flow
  1. Nios® V processor runs the Bootloader via SDM from the on-chip memory.
  2. Bootloader via SDM communicates with the configuration flash and locates the Nios® V software.
  3. Bootloader via SDM copies the Nios® V software from the Configuration Flash into on-chip RAM / external RAM.
  4. Bootloader via SDM switches the Nios® V processor execution to the Nios® V software in the on-chip RAM / external RAM.