[U-Boot] [RFC PATCH] arm: zynqmp: Add ZynqMP minimal R5 support

[Evangelista, Daniel]

Hello,

I have recently been investigating u-boot for booting VxWorks on to the APU and an RPU core of a ZU+ ZCU102 Rev1.1. For some general context, it would be ideal if it were possible to run u-boot on an RPU core to boot VxWorks on to the APU and RPU, instead of running u-boot on the APU.

I came across this post (by Michal Simek at xilinx.com) describing minimal support for the R5 which was tested on a ZCU100 Rev C. I compiled and ran the u-boot source with the R5 defconfig, however was not able to get it to run when programmed on to the ZCU102 (no serial data, R5 program counter cycling between 0x0, 0x2, 0x4...0xC, 0x0...). To program it, I placed the binary in memory over JTAG and commanded the CPU to jump to the address (I tried 0x0, 0x1000000, and 0x2000000 based on the R5 defconfig CONFIG_SYS_TEXT_BASE= 0x10000000).

Can you provide any insight as to why this may be and what I can try to fix it? I also noticed that this post specifically mentions using a u-boot.elf, but when I compile the u-boot source a u-boot.elf is not generated, only a u-boot.bin which is what I tried and failed to get working. I suspect there will be more work to be able to boot VxWorks on both processors, but simply having u-boot run would be a great first step.

Thank you,

Dan Evangelista