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Ric2
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2 years ago

HLS Avalon interface data width implementable only with 2^N numbers

Hi, this is about a second issue we have while migrating an IP core from HLS workflow to new sycl HLS tools (first is here, might be related but this one stand s for its own as well) . The HLS defin...
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Ric2's avatar
Ric2
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2 years ago

Hi again, I'm going to add some more specifics to the problem decribed above. As said, we intend to implement an Avalong Streaming interface with the sycl HLS (icpx) workflow.
The Avalon Streaming specification has this definition for the dataBitsPerSymbol parameter:

The icpx error (Report generation) for non power of 2 numbers is

[ 66%] Building CXX object CMakeFiles/report.dir/src/streaming_data_interfaces.cpp.o
[100%] Linking CXX executable streaming_data_interfaces.report
Compiler Error: The data type carried by _InStream exceeds the bits per symbol. You can either enable the sideband signal 'use empty' or increase the bits per symbol.
Error: Optimizer FAILED.

Note 1: The error is generated after compilation of the source files while linking.

Note 2: EMU generation of non power of two numbers works.

Note 3: With Intel HLS (i++) project it was no problem to generate this non power of two width Avalon Streaming interfaces.

Hope that helps to identify (and resolve) the problem reported.