Deferred Image Loading - 2023.2 English

Versal Adaptive SoC System Software Developers Guide (UG1304)

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2023.2 English

The PLM supports the Image Store and Deferred Image Handoff features. Based on the scenario, you might have to defer loading a certain subsystem image in the PDI after a certain boot milestone, or defer the handing off to a certain subsystem image. This establishes a certain boot order and can be used to decrease boot time.

Image Store

The Image Store feature enables PDI files to be stored in DDR memory and subsequently used to load specified images within the PDI. This functionality is intended to facilitate partial reconfiguration, subsystem restarts, and more, all without relying on external boot devices.

Additionally, the Image Store can serve as the secondary boot device for accessing the PDIs saved in the DDR memory. For more information, see the Image Store Wiki.

Deferred Image Handoff

You can pass the delay_handoff attribute to the selected image IDs in the BIF file, which is an input to Bootgen. The PLM reads the delay_handoff attribute and defers the handoff of the images till the end of boot PDI load. In other words, the images with the delay_handoff attribute specified, only start running after the images without the delay_handoff attributes start their run. Deferred Image Handoff is supported for both full PDIs and partial PDIs.