GSoC, RTEMS, Software

GSoC 2018: Final Report

This is the final report of the work done under GSoC’18 with the RTEMS community. I’ll begin with a summary of all the work done during this summer and will then move towards the corresponding code and documentation developed throughout the timeline.   Porting SDIO driver to RTEMS and benchmarking Student:- Udit Kumar Agarwal Mentors:- Christian Mauderer, Punit Vara Original proposal link: Here Weekly updates:- Project tickets:-  ticket#3429, ticket#3430, ticket#3428 Github Repository:– ABSTRACT RTEMS, being an open-source hard real-time operating system, is already supported by a vast community of developers, hobbyists, and industrialists. With its full application, it…

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ARM, Benchmark, File system, FIO, GSoC, RTEMS, Software

Benchmarking RTEMS Filesystems using FIO

Hi, In this post we will explore FIO’s RTEMS port and how it can be used to benchmark RTEMS filesystems and drivers. First, let’s have a quick look at all the RTEMS filesystems: RTEMS FILESYSTEMS RTEMS supports mainly two types of filesystems: Network and Physical fs. Benchmarking support for networking filesystems isn’t yet available. However, nearly every other physical filesystem can be benchmarked and contrasted. Heap-based file systems are those which uses malloc() for file allocation. In other words, they reside completely on heap memory. These are mainly used to provide basic directory/file management even if there is no dedicated…

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CAM, GSoC, mmccam, RTEMS, SDIO

RTEMS SDIO driver: Current progress

Hi, this post mainly concerns with the current progress of SDIO driver’s implementation on RTEMS. In a nutshell, driver is able to detect, initialize the type of card. However, the part concerned with registering the partitions of the card as RTEMS disks is still buggy. So, I’ll discuss some of the bugs which were previously resolved and the ones that are still left. Starting with a very short introduction of how MMCCAM driver is being interfaced with SDHCI driver: Part 1: Interfacing Complete interfacing task is done mainly via these two files: nexus_devices.h #ifdef RTEMS_BSD_MODULE_MMCCAM SYSINIT_MODULE_REFERENCE(cam); SYSINIT_MODULE_REFERENCE(mmcprobe); SYSINIT_MODULE_REFERENCE(sdda); #endif /*…

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CAM, FreeBSD, GSoC, mmccam, RTEMS, SDIO

Backporting MMCCAM/SDIO framework to FreeBSD head 642b174dadd

My phase 2, GSoC objectives includes Backporting the current(rev: d6756a3ac8 ) MMCCAM framework to FreeBSD head 642b174dadd and then importing it to RTEMS. This post mainly concerns with intricacies and workarounds during the backporting process. Backporting is a process that enables old kernels run a latest driver. MMCCAM framework is one such enhancement in the past few months that enables FreeBSD to talk to devices behind the SDIO bus. It’s a major architectural change, that enables further driver development for devices on SDIO bus. So, first step during backporting is to finalize the revisions from which driver will be imported(d6756a3ac8…

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Benchmark, FIO, GSoC, RTEMS, Software

[GSoC Phase-1] Porting FIO to RTEMS

Hi all, This post covers most of my learnings during phase one of GSoC with RTEMS. My main goal of phase 1 was to port an IO benchmark to RTEMS. Towards this, various benchmarks were compared and fio was finalized for the import. FIO is a pretty much widely accepted and highly configurable IO benchmarking tool, which supports a number of large number of different OS and now RTEMS is among one of them. Following were the major considerations i learned while porting a 3rd party user-space tool to RTEMS(I’ll try to generalize as much as possible, but there will…

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Benchmark, CAM, File system, FreeBSD, GSoC, mmccam, SDIO

microSD Card benchmarking on BeagleBone Black

Hi all, I have been recently involved in benchmarking two different device drivers of FreeBSD ,namely SDHCI and the SDIO driver to compare their relative performance under different circumstances. Here, I will summarize my results, possible conclusions and the benchmarking procedure. Before moving towards benchmarking, i’d prefer going through this article. It really good and provides a great overview of how data is transferred to disk, different APIs available. This will surely help you selecting options for the benchmark. Benchmarking procedure I initially experimented with different benchmarks like iorate, iozone, fio, bonnie++ etc but the one i really liked was…

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GSoC Project Introduction : Importing SDIO stack and Benchmarking

Hi all, This post is basically an introduction of my GSoC 2018 project under RTEMS. It marks the beginning of a series of blog posts that will be put on ( under the tag ‘GSoC’ ) for documenting my work throughout the time span. Before moving on, I would like to thank RTEMS project and Google for giving me this opportunity of working on a highly fruitful Open source project, whose proposal can be found here ,under the mentorship of Christian Mauderer and punit vara. It would be great working with you both :). Some important links: Wiki page: Project…

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ARM, CAM, FreeBSD, mmccam, SDIO, Software

Building FreeBSD’s SDIO driver for BeagleBone Black

Hi all, This post mainly concern with building FreeBSD’s SDIO driver for BeagleBone Black by cross compiling it on AMD platform. I had few unresolved issues with the master branch of current FreeBSD tree. So, for this i used another unofficial branch: . It does have the required KERNCONF file with stable SDIO driver. A lot of steps below are similar to the one given on:  with slight but inevitable changes. Procedure:  Before proceeding you need to first install git. sudo pkg update -f sudo pkg install git  Setup project directory by mkdir /BBB  Clone the repository to…

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FreeBSD, GSoC, Software

Setting up FreeBSD environment on virtualbox

Hi all, In this post we will review the procedure of setting up the FreeBSD environment on VirtualBox along with setting up Internet on the guest OS(this was pretty tricky!).BTW, my host OS is Ubuntu 14.04 So, I am assuming you have already installed VirtualBox as per your host OS and has downloaded the FreeBSD amd64 iso image(If not you can do it from here and extract it appropriately to get a .iso file. Installing FreeBSD on VirtualBox Installing FreeBSD on virtual box is pretty straight forward, just insert use the downloaded iso to boot up the VM with default…

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File system, Hardware, NAND/NOR

Effect of file-system on sd card’s performance

I had a task to compare different protocols( and their different implementations) like SD, SPI, SDIO(in FreeBSD’s MMCCAM implementation) by accessing SD Card. Now, for unbiased comparison, I must eliminate file system type in sd card from the equation. In this blog post, I’ll discuss/share my findings of the file-systems used for the card(SD and MMC) and how they affect its performance. So, let’s start with a very quick introduction to some basic concepts: Introduction MMC- Multimedia Card is a memory card unveiled in 1997 by SanDisk and Siemens based on NAND flash memory. eMMC is a regular MMC in…

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