Bare Metal VCU118 capability (similar to Arty100T) and Update to VCU118 documentation

[BMorgan1296]

Background Work

• Yes, I searched the mailing list
• Yes, I searched the documentation

Feature Description

Hi,

I have searched the mailing list and found this which relates to getting the VCU118 to handle bare metal programs loaded onto an SD card.

I would like to know how to change the configs of the VCU118 to support only bare metal programming using the TSI/UART interface just like with the Arty100T.

I have found that the bootrom for the VCU118 is different to the Arty100T due to the VCU118 config.scala including 'WithSystemModifications -> BootROMLocated' within. However, I have tried swapping out the bootrom here with one from the Arty100T, but I could not send a program over and get any output using the same commands as the Arty. I have also tried commenting out the 'BootROMLocated' section in the hopes that a different one would be loaded for the VCU118. No luck as of yet.

Clearly I have missed something, but I need help as to what. If I could be pointed to the right way to implement this, I would be happy to contribute.

Update to VCU118 Documentation

The documentation for the VCU118 should also have a notice saying to use the SD card a PMOD to SD card adapter is required. I know that the board specification file says it, but unfortunately I didn't look there first before I went to the shops!

Motivating Example

I am trying to send binaries over to the Rocket or BOOM CPUs implemented on the FPGA. I have no need for a full Linux boot as I am wanting to compare and benchmark the CPUs running certain tasks. So I would like a way to interface with the VCU118 just like the Arty100T.

[jerryz123]

Alas, I have not had the time to do this. I would be more than happy to shepherd a PR for this.
I would approach this by creating a new VCU118FPGATestHarness that contains only a UART interface for UART-TSI, getting a simple config working with that, then adding back the DDR and GPIO interfaces.

[BMorgan1296]

I'll give it a go and report back, thanks!

[jerryz123]

Feel free to open a WIP PR at any point with your work.

[BMorgan1296]

Got it working but may need some code improvements. Have confirmed it with a VCU118, sent a binary to it and it worked the same as with the Arty100T.

#1892 (comment)