Examples and Ref Apps

[ReinhardKeil]

The examples "Hello", "vStream_Audio", and "vStream_Video" should be all in the folder "example".
Names: FVP_Hello, FVP_Audio, FVP_Video

Structure
Examples/FVP_Hello/FVP_Hello.csolution.yml
Examples/FVP_Hello/requirements.txt # Python requirements
Examples/FVP_Hello/project/FVP_Hello.cproject.yml
Examples/FVP_Hello/board/.... # the layers
Examples/FVP_Audio/.... # same structure

All examples should be configured for the targets SSE-300, 310, 315, 320 similar to:
https://github.com/Arm-Examples/cmsis-mlek/blob/main/template/audio/mlek_audio.csolution.yml#L68

The examples should work out-of-the-box including meaningful simulator configurations.

Like in MLEK the examples should be also registered as reference applications, which allows it to retarget to physical boards.

Details see https://github.com/ARM-software/AVH/blob/main/Overview/Overview.md

Note: the best way to maintain the different layers is to generate a scrip that copies the layers from the Board folder to each example.

Also the 'app_main' functions in each of the examples should be simplified to the essence. Just use "assert" macros instead of printf error output.

[VladimirUmek]

I would rather add requirements.txt to board layer:
./board/Corstone-300/requirements.txt
and add related information to
./board/Corstone-300/README.md

Example is generic, only depends on vStream API and can be used with any hardware that implements vStream drivers. When used with hardware, requirements.txt for Python packages is pointess.

[ReinhardKeil]

@VladimirUmek yes that works for me. Add requirements.txt to the board layer (then it is effectively on just one place).

[ReinhardKeil]

Could you please work on this:

Also the 'app_main' functions in each of the examples should be simplified to the essence. Just use "assert" macros instead of printf error output.

I believe that there are still too many calls to the vstream functions. Essentially, just need a copy loop is required to achieve what we explain here https://github.com/ARM-software/AVH/tree/main/Overview

[VladimirUmek]

Will clean up printf statements and config defines on top of the file (already planned).

Otherwise application is as simple as possible. Copy loop is here and it could not be simpler.

[VladimirUmek]

See PR #61 for updated example.

I decided not to use classic assert, since it is causing display error in IDE, see below, the red underline for each statement, due to "Use of undeclared identifier '__promise' that apparently clangd does not know.

[ReinhardKeil]

Now clearer. Review the following:

• ASSERT uses exit(0); This might not work correctly.
• app_config.h should move to app_main.c so that the file is easier to spot
• consider to print EOT at the end to stop simulation

Suggest that @RobertRostohar reviews this too

[RobertRostohar]

It looks fine to me.
A few additional comments:

• consider using ASSERT also in the loop instead of just exiting the loop with break in case of fatal erros
• function init_streams should be static