BeagleBoard/GSoC/2019Proposal/PRUUserSpaceAPI-PratimUgale

=Proposal for PRU User Space API project=

This project aims to provide an API for different programming languages to load/unload firmware and communicate with the PRUs from User Space.

Student: Pratim Ugale Possible Mentors: Kumar Abhishek, Zubeen Tolani Wiki: https://elinux.org/BeagleBoard/GSoC/Ideas#PRU_User_Space_API GSoC: GSoC entry

=Status= This project is currently just a proposal.

=Proposal= I have completed the requirements listed on the ideas page and have opened a pull request here.

About you
IRC: pratimugale Github: Pratim Ugale School: Veermata Jijabai Technological Institute (VJTI), Mumbai Country: India Primary language: English Typical work hours: 08:00 to 21:00 IST (GMT+ 05:30) Previous GSoC participation: I haven't participated in GSoC before. Having used open source technologies and programming forums before to solve my problems, I want to start contributing back to the community through GSoC and then continue on my own.

About your project
Project name: PRU User Space API

Description

 * Introduction


 * This project will enable the control of the Beaglebone's PRUs from a User Space Client Program on the ARM. The PRU is a dual core micro-controller system present on the AM335x SoC (TI's ARM A8 based chip) which powers the BeagleBone. It is meant to be used for high speed jitter free IO control. Being independent from the linux scheduler and having direct access to the IO pins of the BeagleBone Black, the PRU is ideal for offloading IO intensive tasks.


 * The User Space Client Program must be able to
 * Load firmware into the PRU cores
 * Control PRU execution (start, stop, etc.)
 * Manage resources (memory, interrupt mappings, etc.)
 * Provide a method to send/receive messages
 * The remoteproc framework allows different platforms/architectures to control (power on, load firmware, power off) remote processors while abstracting any hardware differences
 * A scalable TLV (table, length, value) Table (Resource Table) is used to inform the remoteproc driver about the remote processor’s available resources. To configure the Resource Table, one typically needs to modify up to three things
 * Event-to-channel mapping
 * Channel-to-host mapping
 * Number and location of vrings
 * Rpmsg is a Linux framework designed to allow for message passing between the kernel and a remote processor. It uses a virtual ring buffer (VRING) that allows one to post messages to this buffer. Then, interrupts are used to notify the PRU/ARM that messages are in the buffer. RPMsg provides scalability for integrating individual PRU peripherals with the respective driver sub-systems.


 * The Project
 * The new Remoteproc and RPMsg drivers will be used for the ARM<->PRU communication.


 * (***The main task of the project is that different programming languages should be able to boot up the PRU and load/unload the firmware on it, while simultaneously being able to communicate with it using RPMsg. Also it will reduce the number of commands that the user will have to type to get the PRU up and running.***)
 * The 


 * Deliverables


 * The project will consist of the following components:


 * The user space libraries for the API in different programming languages. The API will use UNIX sockets to communicate with the Daemon server.
 * The Daemon: Written in python, the daemon will listen to the requests, use language bindings to call the appropriate Remoteproc and RPMsg functions, and pass the corresponding return value back to the userspace program.
 * The PRU Remoteproc and RPMsg device drivers
 * The PRU firmware
 * Documentation: This is one of the most important aspects of the project. Currently, the documentation regarding the PRU remoteproc and RPMsg drivers is scattered, incomplete and outdated. Also, there is a steep learning curve to program the PRUs. I plan to provide an exhaustive Documentation along with hands-on examples so that one can utilize the PRU to its full capacity.

Timeline
Provide a development timeline with a milestone each of the 11 weeks. (A realistic timeline is critical to our selection process.)


 * Before Community Bonding (Until 6th May):
 * Study the documentation of Remoteproc and RPMsg as much as I can.
 * Figure out how I'll be structuring the API, the Daemon etc
 * Community Bonding Period(6th May - 26th May):
 * Unavailable until 15th May due to End Semester Examinations
 * Week 1 (27th May - 2nd June):
 * Milestone #1
 * Week 2 (3rd June - 9th June):
 * Make the Introductory Youtube Video
 * Week 3 (10th June - 16th June):
 * Milestone #3
 * Week 4 (17th June - 23rd June):
 * Milestone #4
 * Week 5 (24th June - 30th June):
 * Milestone #5
 * Week 6 (1st July - 7th July):
 * Milestone #6
 * Week 7 (8th July - 14th July):
 * Milestone #7
 * Week 8 (15th July - 21st July):
 * Milestone #8
 * Week 9 (22nd July - 28th July):
 * Milestone #9
 * Week 10 (29th July - 4th August):
 * Some porting effort required for reusing legacy PASM projects.
 * Week 11 (5th August - 11th August):
 * Documentation for all the languages along with examples.
 * The Documentation will also contain the errors one might expect while working with the PRU and how to resolve them.
 * Week 12 (12th August - 18th August):
 * Buffer Period in case of any disturbance in the timeline.
 * Make the Completion Youtube Video

Experience and approach
I am in my sophomore year of engineering, doing Information Technology. I am currently enrolled in a "Computer Organisation and Architecture" course which motivated me to learn more about the PRUs. I have worked with C, Python, Java, Makefiles, Vimscript before. I have learnt Linux driver development over the Internet in the past few months (I have implemented basic programs, and listed the errors I encountered on my github profile here). I have worked with the Arduino UNO and ATMega boards before (made a self balancing and line following bot using PID algorithm in college). I have always been using Linux(Ubuntu) as my primary OS, so getting along with Embedded Linux won't be a problem. Hence, I am confident that I'll be able to complete the given project in due time.

Contingency
What will you do if you get stuck on your project and your mentor isn’t around?

While working with open source software, one thing I realised for sure is that one has to be self-sufficient. Knowing how to use a search engine effectively is also an important skill. I like to give my best before asking anyone else for help when I’m stuck with any problem and I consider it to be a way I actually learn and become independent.

However, if I get terribly stuck on a problem, I shall:
 * Work on the Documentation.
 * Test more firmware examples with the project and do debugging.
 * Will use:
 * 
 * 

Benefit
If successfully completed, what will its impact be on the BeagleBoard.org community?

This project will allow larger programs to be developed in the programming language of the user's choice. Right now, to execute some code on the PRUs, intermediate knowledge about the remoteproc and RPMsg drivers is required. Mar 08 05:03:15 : To make it easy to use interface and standards for the PRU. Right now, we have to execute commands to get some code loaded onto the PRUs, by echoing into the sysfs entries. Also, the remoteproc mechanism allows to communicate with the PRUs using char device entries (mostly, and can be configured). The APIs need to provide a way, in different languages, to be able to read and write message to and from the PRUs within the program itself. Zubeen Tolani(zeekhuge)

Future Work

 * In the future, the project will be expanded to support many more programming languages.
 * The Documentation will always be updated to use the newest methods that are developed.

Suggestions
Is there anything else we should have asked you?