Add niosv

[whitepau]

Adding a New Sample(s) - Nios V

Description

This code sample demonstrates how to use an FPGA IP produced with the Intel® oneAPI DPC++/C++ Compiler with a NIOS V soft CPU in an IP Authoring workflow.

This is the first pass at this code sample.

@yuguen-intel can you please review

• readme (for understandability/process)
• sample.json
• kernel at kernels/simple_dma/

@jarrodblackburn can you please review

• readme (for correctness)
• kernel at kernels/simple_dma/
• Intel® Quartus® Prime and Platform Designer stuff

I'll get Khai Liang to have a look after you, or if you don't have time

Checklist

Administrative

• Review sample design with the appropriate Domain Expert:
• If you have any new dependencies/binaries, inform the oneAPI Code Samples Project Manager

Code Development

• Implement coding guidelines and ensure code quality. see wiki for details
• Adhere to readme template
• Enforce format via clang-format config file
• Adhere to sample.json specification. https://github.com/oneapi-src/oneAPI-samples/wiki/sample-json-specification
• Ensure/create CI test configurations for sample (ciTests field) https://github.com/oneapi-src/oneAPI-samples/wiki/sample-json-ci-test-object
• Run jsonlint on sample.json to verify json syntax. www.jsonlint.com

Security and Legal

• OSPDT Approval (see Project Manager for assistance)
• Compile using the following compiler flags and fix any warnings, the falgs are: "/Wall -Wformat-security -Werror=format-security"
• Bandit Scans (Python only)
• Virus scan

Review

• Review DPC++ code with Paul Peterseon. (GitHub User: pmpeter1)
• Review readme with Tom Lenth(@tomlenth) and/or Project Manager
• Tested using Dev Cloud when applicable

[yuguen-intel]

Suggested change

	for (unsigned int i = 0; i < (length / 4);
	i++) // will be testing with Nios V where an int is 4 bytes
	{
	destination[i] = source[i];
	}
	// will be testing with Nios V where an int is 4 bytes
	for (unsigned int i = 0; i < (length / 4); i++) {
	destination[i] = source[i];
	}

[yuguen-intel]

Is this comment meant for the users or to remind the developer to test something?

[whitepau]

for users; to explain why we divide legnth by 4. do you think memcpy would make more sense here? @jarrodblackburn can you use memcpy on the Nios® V softcore processor?

[yuguen-intel]

ah understood, then I think it should be rewritten as follows:

Suggested change

	for (unsigned int i = 0; i < (length / 4);
	i++) // will be testing with Nios V where an int is 4 bytes
	{
	destination[i] = source[i];
	}
	// will be testing with Nios V where an int is 4 bytes
	constexpr kSize = length / 4
	for (unsigned int i = 0; i < kSize; i++) {
	destination[i] = source[i];
	}

[jarrodblackburn]

memcpy is present for Nios V but this is the kernel code so not it's applicable here. This change is fine given the DMA is only moving integers. The division was in the original code since I tend to keep everything expressed in bytes (unaligned DMAs get confusing if you deal with a mix of words and bytes).

[whitepau]

it shouldn't be a constexpr anyway because length is a runtime parameter. I'll write it like this:

  void operator()() const {
    // This loop does not handle partial accesses (less than 4 bytes) at the
    // start and end of the source/destination so ensure they are at least
    // 4-byte aligned
    for (unsigned int i = 0; i < (length_bytes / 4); i++) {
      destination[i] = source[i];
    }
  }