AWS F1 Custom pBlock

Hello,

Thank you for reaching out to us on this topic. The CL build flow allows users to define user specific pblocks and assign modules to it. Following example shows an xdc that creates pblock for the CL_DRAM_DMA design. The XDC is read before link_design stage:

• https://github.com/aws/aws-fpga/blob/master/hdk/cl/examples/cl_dram_dma/build/constraints/cl_pnr_user.xdc
• https://github.com/aws/aws-fpga/blob/master/hdk/cl/examples/cl_dram_dma/build/scripts/create_dcp_from_cl.tcl#L247

We have few follow up questions:

• Do you see any errors when creating pblocks using GUI?
• Could you try creating pblocks in GUI using post_link.dcp?
• Were you able to create pblocks using xdc?

Thanks! Chakra

Hi Chakra. I ended up creating pblocks from xdc. This seems to work well. I did try the gui but it wasnt taking it well for some reason. When I was trying to save the constraints using the gui, it saves it in some temp folder under ".Xil". But then when I go there, its not there.

Sai.

Hello Sai,

The ".Xil" is a temporary folder created by Vivado tool to save all the intermediate files used by the tool. So I would like to suggest few options here:

• If you are creating pblocks in the GUI, please make sure to save the DCP after creating pblock constraints and use this DCP during builds.
• Alternately, you should be able to view the TCL constraints used by the tool in "tcl console" window when you create pblocks in the GUI. You may copy these commands into a seperate xdc file and use it for the builds.
• Also, please try running write_xdc <filename>.xdc in the tcl console to dump all the constraints into an xdc file.

Hope this helps. Please reach out to us if you have any questions or need any details.

Thanks, Chakra