[FAQ] AM6548: How to get PRU Ethernet working in U-boot on AM65x Linux SDK 9.1?

This feature is not fully functional in SDK 9.1. In order to get PRU Ethernet working in Uboot, you need to grab some additional code that was released after SDK 9.1.

Linux version

Use the version of Linux drivers in AM65x Linux SDK 9.1

Uboot version

Use the latest version of ti-u-boot: https://git.ti.com/cgit/ti-u-boot/ti-u-boot/log/?h=ti-u-boot-2023.04-next

Make sure it has Danish's patch set from 
https://git.ti.com/cgit/ti-u-boot/ti-u-boot/commit/?h=ti-u-boot-2023.04-next&id=61ea32c0eb0c2d827a7ebc52a2befe8dfbd1de56
through
https://git.ti.com/cgit/ti-u-boot/ti-u-boot/commit/?h=ti-u-boot-2023.04-next&id=654724bbe4dae24cf91a085f2182f734b7db0554 

PRUETH firmware version

The current ti-u-boot ICSSG driver (as of Feb 27, 2024) was written to work with the version of ICSSG firmware bundled in AM65x 9.1 SDK (i.e. Version REL.PRU-ICSS-ETHERNET-SWITCH_02.02.12.08)

Steps to run

The steps documented in SDK 9.1 are out-of-date (as of Feb 27, 2024). We plan to update them for AM64x SDK 9.2: https://software-dl.ti.com/processor-sdk-linux/esd/AM65X/09_01_00_01/exports/docs/linux/Foundational_Components/U-Boot/UG-Network.html#sample-script-for-am65-sr2

For the updated uboot driver, you only need to select icssg interface "setenv ethact icssg2-eth" and run the dhcp command. There is no need to load PRUs manually, the driver takes care of loading the PRU cores.