Intel® Arria® 10 SoC UEFI Boot Loader User Guide

ID 683536
Date 12/15/2017
Public
Document Table of Contents

1.5.8. Early I/O Release

Task time: 30 minutes

Early I/O release enables DDR functioning prior to programming the core raw binary file (RBF). This feature provides a faster boot time because the shared I/O and hard memory controller I/O are configured and released for immediate access by the HPS. Early I/O release also enables availability of the shared I/O so that device can obtain the core RBF from the TFTP server instead of flash. The CSS then configures and releases the FPGA fabric allowing the HPS to have access. Early I/O release also provides early response in time critical systems.

The peripheral RBF configures shared I/O, hard memory controller I/O, and hard memory controller settings such as memory type, frequency and timings. The core RBF configures the FPGA fabric, FPGA I/O and FPGA PLL settings. You can choose to combine the peripheral and core RBF into one RBF that configures both the FPGA fabric and the I/O Control Shift registers (IOCSRs). Using a combined RBF creates a performance penalty that is much slower than splitting the RBFs. When you split the RBFs, the core RBF loads into SDRAM instead of on-chip RAM from flash providing a larger data transfer block and boosting performance.