Intel Agilex® 7 Hard Processor System Remote System Update User Guide

ID 683184
Date 2/23/2024
Document Table of Contents

E. Combined Application Images

A combined application image is an application image which is able to update the decision firmware and decision firmware data in flash while it is being loaded. The update only happens if the combined image was created with a newer version of the Intel® Quartus® Prime software than the decision firmware that is currently used in the system. Intel® Quartus® Prime software patches have the same version as the Intel® Quartus® Prime software product they patch, so they are not detected as newer.

Note: Combined application image support was added in Intel® Quartus® Prime software version 20.4, to enable a very specific use case where support for deploying and running a factory update image or a decision firmware update image was not deployed in the system. The combined application image enabled deploying new features in the decision firmware (like the max_retry option) by just deploying this special type of application image.
Important: You must provide support for updating the factory image, by having the ability to download the factory update image, write it to flash, and pass control to it. If this is done, you do not need to use the combined application image feature.

The combined application image is up less than 512 KB larger than the regular application image created with the same options and using the same SOF file.

The combined application firmware contains the following components: new decision firmware, new decision firmware data, application image section, and specialized firmware which performs the version checking and the conditional update.

The combined application image always checks the decision firmware version at load time, by looking at the decision firmware copy that was last used successfully. In the cases where it does not need to perform the update, the increase in load time is negligible. In case the update needs to be performed, this adds a few seconds to the load time.

The factory update flow is resilient to power loss. If the power is lost during the update, the next time the power is back up, the factory update image resumes the update process from where it stopped.

The combined application image can be written to flash with both the APIs designed to write application images, and with the APIs and commands designed to write factory update images and decision firmware update images to flash. It achieves this by not having internal pointers that need to be relocated, so it can be written to and loaded from any address in flash.