Posts
69
Following
10
Followers
113
Embedded, open-source, and open-hardware enthusiast interested in passing knowledge to next generation. OpenHub https://openhub.net/accounts/ppisa/positions . For our computer architectures education see https://comparch.edu.cvut.cz/ .

Apache #NuttX International Workshop 2025 will be held on this Thursday and Friday (16-17th October 2025) https://events.nuttx.apache.org/ It will be accessible on site (Costa Rica - home location of original author, Gregory Nutt) and online. The NuttX RTOS is POSIX based alternative for processor systems and MCUs where Linux kernel does not fit. But thanks to following POSIX and Linux principles it allows writing applications (with some care) which are easily portable between GNU/Linux, NuttX, RTEMS and other real POSIX alternatives. The list of supported platforms is extensive. The #PX4 Autopilot project which is part of vendor-neutral https://dronecode.org/ operating under #Linuxfoundation umbrella. The system is used in lot of fitness tracker, some smartwatches, Sony earbuds, cameras on the Moon, industrial and automotive applications.

0
2
2

Thanks to all AVC SH team members for providing superior service to #LinuxDays yet another year in the long row. The recordings at https://www.youtube.com/@LinuxdaysCz/videos

0
3
8

- @turris News! by Michal Hrušecký, Marek Novotný

yt-dlp "https://www.youtube.com/watch?v=PmbxCu-Yt7Q"

0
1
0
Edited 8 days ago

Michal Lenc will present about his #CANbus subsystem integration into #RTEMS space grade system on #LinuxDays on on Sunday October 5 from 11:00 CEST. This time in the Czech language. See the entry. The article presented at International CAN Conference is there, RTEMS mainline documentation, more information at CTU FEE CAN projects site. Update: Recording (in Czech)

0
1
2
Edited 10 days ago

OTREES #cvut booth at #LinuxDays 2025 presenting our CAN/CAN FD projects for #Linux, #NuttX, #FPGA and #RTEMS. SaMoCon motion control platform driven by pysimCoder rapid prototyping solution for #NuttX with online monitoring and parameters tuning and update uploads through silicon-heaven and NXboot integrated in the frame of Štěpán Pressl’s #GSoC 2025 (will be presented in detail on NuttX Workshop October 16 and 17). More on the booth: #Espressif based kits running NuttX (ICE-V Wireless, see our PMSM project, #ESP32C6 with M-bot platform), AMD/Xilinx Zynq MZ_APO running Linux and #RTEMS, PolarFire SoC, Milk-V Pioneer 64 core 64-bit #RISCV system running #QtRvSim (for CompArch education), #CHROMuLAN data acquisition over uLAN driver, LX_RoCoN system used for ESA projects and lot more to see at our booth.

1
3
7

The #NuttX configuration for Open Alliance TC6/SPI connected T1S MAC-PHY for chosen and tested #ARM and #RISCV boards has been updates as well

0
0
2
Edited 26 days ago

#NuttX Support for IEEE 802.3-2022 10BASE-T1S/L #Ethernet using Open Aliance SPI MAC-PHYs implemented by Michal Matias from #CVUT in frame of #GSoC2025 has been fully merged into NuttX mainline. The common part resides at drivers/net/oa_tc6. #ESP32C6 mapping and mapping for SAVM71-Xplained Ultra are good examples for straightforward extension to other MCU and board NuttX SPI interfaces. The accompanying plcatool for Physical Layer Collision Avoidance parameters configuration matching OA-TC14 specification is another contribution.

1
4
6

🇩🇪Auch dank eures Engagements werden Belgien, Finnland und Tschechien der im Oktober nicht zustimmen! Die Bundesregierung ist aber immer noch unentschieden, ob sie Briefgeheimnis und sichere Verschlüsselung retten will. Werdet jetzt laut: https://www.patrick-breyer.de/beitraege/chatkontrolle/#WasTun

1
1
0

🇬🇧Public pressure works: Belgium, Finland & Czechia will NOT approve the mass surveillance law in October. But other governments whose vote is crucial are still on the fence. Urge them to protect our digital privacy and encryption now: https://www.patrick-breyer.de/en/posts/chat-control/#WhatYouCanDo

0
10
0
Edited 1 month ago
Thanks for this finding and because I have not seen a link added to your LWN article in this thread yet, I add it there https://lwn.net/Articles/1034849/ The need to reliably preserve our community history
0
0
0

Jonathan Corbet

Sigh ... it seems that the Groklaw domain has fallen into the hands of people who ... are inconsistent with the history of this site. I guess it's time to replace all the links on LWN with wayback machine equivalents.

https://fossforce.com/2025/08/groklaw-domain-hijacked-site-now-serving-crypto-content/
4
16
19

In our latest guest blog post, Matt Young introduces an Automated Triple Modular Redundancy EDA Flow for Yosys!

https://blog.yosyshq.com/p/tamara-towards-a-triple-modular-redundancy-pass-for-yosys/

0
5
0

Hot take: for critical infra, all firmware running on devices operated by public entities should be compiled and audited by these public entities.

Vendors should be required to supply source code and assist in compilation, flashing and verification; but the operator should have the means to introspect and verify any part of such deliveries independently.

Then this entire mess of a Polish train manufacturer never could have gone off the rails.

Re: https://www.ifixit.com/News/112008/polish-train-maker-is-suing-the-hackers-who-exposed-its-anti-repair-tricks

0
6
0

@ljs @vbabka Thanks to both. Yes, I remember to read about new/concurrent/RCU friendly VMA tree at #lwn some time ago, I try fit more letters in the triangle, on the other hand R-B tree is something which students know… but showing maple can be motivation to search for more modern data structures in their future projects, I mention user-space RCU, cuckoo hashing from Knot DNS as well as others.

struct radix_tree_root	page_tree; /* radix tree of all pages */

Good catch, it seems to have gone in 4.17 kernel, when it has been renamed to

struct  radix_tree_root i_pages;

and it has been changed to struct xarray in 4.20. So this is evolution.

So it should be updated to be modern.

VPFN (virtual page frame number) and physical (P)PFN is used by me to distinguish what is view and meaning of address bits before and after MMU translation. It highlights that translation cares only about page sized frames no full addresses. It seems that it is not only mine local invention - used even on WikiBooks/The_Linux_Kernel/Memory.

The goal is to provide mainly an overall picture not details to start hacking and contributions to the kernel so if it is “roughly” appropriate is important. But if some students are attracted to contribute to Linux it would be great outcome. We have more students contributing to #NuttX which is lower bar for starting. But some have contributed drivers to Linux as well.

0
0
1

@ljs Congratulation to the book publication. I hope to find some time one day and look at it myself or at least, will be able to make it available to my students with help of the #cvut library.

I have plea for you and @vbabka , I prepare for the next round of the Advanced Computer Architectures course. It is focused mainly to basic knowledge about progress from pipelined execution (basic course) to the super-scalar one in nineties to understand even later designs including GPUs, NUMA, etc. But I include even some amateur glimpse how is memory used in real system which is based on my already dated wander through Linux kernel sources. I would be very happy if you find time to look at the diagram on the slide 114 of the Lecture 6 and provide me feedback if there is something which is not true or have been changed considerably so I should correct it to not mislead my students. There are some more slides around where your expert feedback can save students from misleading information as well.

0
0
1

Hello 🌏 ! This is #phosh's new fediverse presence. It'll have phosh's release announcements and posts/boosts of related projects. Looking forward to an interesting and bright Linux mobile future 📱 phosh .

0
5
1

Thorsten Leemhuis (acct. 1/4)

ICYMI: the recording of @corbet's recent talk "Three Decades in Kernelland" recently became available:

https://www.youtube.com/watch?v=hNLBGiwfBSI

From the abstract[1]: The project has been going for well over 30 years. From its beginnings on floppy diskettes and beige boxes through to its current home in pockets and unseen data centers, the kernel project has been a constant exercise in rapid development and adaptation. I have been present for almost all of the kernel project's history as an observer, contributor, maintainer, and more; all that experience will be boiled down into a fast-moving tour of how the got to where it is, what makes it successful, and what may be coming next.

[1] https://ossna2025.sched.com/event/1zfit/three-decades-in-kernelland-jonathan-corbet-lwnnet

1
4
1

@leonerd @oshpark @benhencke Nice option with display and local control. But if you want really cheap scopes, function generators, counters etc. then the #cvut team from another department provides firmware for cheap STM32, PICO and even Arduino (sic, some people are not willing to move forward and colleagues support them too) boards based Software Defined Instruments. For the PC side, see DataPlotter (github , with Nucleo F303RE 5 Ms/s 12 bit, STM32L412KB 2x 5 Ms/s, with Arduino 15 kS/s, with Raspberry PICO 1x 500 KS/s or 2x 250 kS/s) and older zero_elabviewer for even more boards. All firmware is available for download and documented in theses (unfortunately usually in Czech language, but colleagues or me can help).

0
0
0
Edited 3 months ago

Summer 2025 #cvut defended theses by OTREES / “my” students:

See the last OTREES theses list for link to repositories and more

Another related theses from #cvut Faculty of Information Technologies mentored by Michal Ĺ tepanovskĂ˝ to mention:

Stay tuned next summer as well, there is student interested in thesis to add MMU to #QtRvSim

0
2
3
Show older