Assigning AXI Interfaces to PLRAM - 2023.2 English

Vitis Unified Software Platform Documentation: Application Acceleration Development (UG1393)

Document ID
UG1393
Release Date
2023-12-13
Version
2023.2 English

For platforms that support PLRAM use the --connectivity.sp option as previously described in Mapping Kernel Ports to Memory, but use the name PLRAM[id] to specify the bank. Valid PLRAM banks supported by a platform can be found in the Memory Information section reported by the platforminfo command.

For example, in the Alveo U250 platform the following PLRAM information is reported:

  Bus SP Tag: PLRAM
    Segment Index: 0
      Consumption: explicit
      SLR:         SLR0
      Max Masters: 60
    Segment Index: 1
      Consumption: explicit
      SLR:         SLR1
      Max Masters: 60
    Segment Index: 2
      Consumption: explicit
      SLR:         SLR2
      Max Masters: 60
    Segment Index: 3
      Consumption: explicit
      SLR:         SLR3
      Max Masters: 60

To access the PLRAM you would use the following command for example:

--connectivity.sp cnn_1.weights:PLRAM3
Tip: To reduce latency and improve performance the kernel accessing this PLRAM should be placed into SLR3 in addition to Assigning Compute Units to SLRs on Alveo Accelerator Cards.