Intel Software: Intel FPGA SDK for OpenCL

Type: Answers

Area: OpenCL



Why there is no description of the OpenCL library AVALON_MEM element for some signals?

Description

The OpenCL programming advance guide explains about the RTL element required for the library for external memory.

For the AVALON_MEM element defined in the code example, the corresponding RTL module ports are as follows:


output avm_port0_enable,
input [511:0] avm_port0_readdata,
input avm_port0_readdatavalid,
input avm_port0_waitrequest,
output [31:0] avm_port0_address,
output avm_port0_read,
output avm_port0_write,
input avm_port0_writeack,
output [511:0] avm_port0_writedata,
output [63:0] avm_port0_byteenable,
output [4:0] avm_port0_burstcount,


There is no assumed correspondence between pointers that you specify with
MEM_INPUT and the Avalon-MM interfaces that you specify with AVALON_MEM. An RTL module can use a single pointer to address zero to multiple Avalon-MM interfaces

 

Both signals in bold are not documented.

 

 

Workaround/Fix

In most applications the avm_port0_enable signal can be tied high, and the avm_port0_writeack signal can be ignored. An updated description will be included in the upcoming programming guide.