Nios® V Embedded Processor Design Handbook

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

4.5.1.1. Nios® V Processor Application Executes-In-Place from Configuration QSPI Flash

The execute-in-place (XIP) option is suitable for Nios® V processor application, when only a limited amount of on-chip memory is available to the processor. This boot option is only available for control block-based devices.

The alt_load() function operates as a mini boot copier that initializes and copies the writable memory sections only to OCRAM or external RAM. The code section (.text), which is a read-only section, remains in the configuration QSPI flash memory region. Retaining the read-only section in configuration QSPI minimizes RAM usage but may limit the code execution performance.

The Nios® V processor application is programmed into the configuration QSPI flash. The Nios® V processor reset the agent points to the configuration QSPI flash to allow code execution after the system resets.

Figure 17.  Nios® V Processor Application Executes-In-Place from Configuration QSPI Flash