Directly Accessing Host Memory on Alveo Accelerator Cards - 2024.1 English

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

Document ID
UG1393
Release Date
2024-05-30
Version
2024.1 English

The PCIe® Slave-Bridge IP is provided on some data center platforms to let kernels access directly to host memory. Only certain Alveo cards support the host memory connection, as reported in the Memory Information section returned by the platforminfo command.

For example, the following information is returned for the Alveo U250 card:

   Name: HOST[0]
   Index: 8
   Type: MEM_DRAM
   Base Address: 0x2000000000
   Address Size: 0x400000000
   Bank Used: No

Configuring the device binary to connect directly to host memory uses the --connectivity.sp command below.

[connectivity]
## Syntax
##sp=<cu_name>.<interface_name>:HOST[0]
sp=cnn_1.weights:HOST[0]
Important: Using host memory also requires changes to the accelerator card setup and your host application as described at Host-Memory Access in the XRT documentation.