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Olof Johansson
Works at Tesla
Attended Luleå University of Technology
Lives in Belmont, CA
3,266 followers|2,425,852 views
Swede in California
  • Luleå University of Technology
    1992 - 1998
  • Balderskolan
    1989 - 1992
Basic Information
Bits and bytes. Software and stuff.
  • Tesla
    2016 - present
  • Google
    2010 - 2016
  • Agnilux
    2009 - 2010
  • Apple
    2008 - 2009
  • PA Semi
    2005 - 2008
  • IBM
    2000 - 2005
  • Effnet
    1997 - 2000
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Belmont, CA
Austin, TX - Luleå, Sweden - Skellefteå, Sweden


Olof Johansson

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Ohhh yes...
After years of hard work the etnaviv team reached an other very important milestone. The gallium driver and the renderonly library got pushed into mesa's git repository and will be released with mesa 17.0 - yeah! This does not mean we are done with development at all. There are
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Olof Johansson

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Here's a really good Q&A directly with Hiroshi from December that I had missed (surfaced not-so-recently on Reddit), with renewed confirmation and clarification that Chrome OS and Android are not merging, but they are getting closer to each other and cross-pollination is happening.
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Olof Johansson

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Nice! I'm guessing price will be significantly above RPi3 though.
+ASUS is getting into the maker board market with their Tinker Board powered by Rockchip RK3288 processor.
Regular readers may remember MQMaker MiQi board, a $35 (and up) development board powered by Rockchip RK3388 quad core ARM Cortex A17 processor, based on Raspberry Pi 3 form factor, but much faster according to benchmarks. Sadly, the board's crowdfunding campaign was not that ...
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Daniel Bos's profile photoMatt Porter (mdp)'s profile photoGregory P. Smith's profile photoPeter Bauer's profile photo
The Asus tinker board will be sold with 2 GB RAM for around 50 Euro without VAT which isn't that expensive. Willi Tarreau has some interesting kernel 4.9 patches for RK3288 (miqi-board). - MiQi SBC news 2017/01
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Olof Johansson

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"[…] Inside of Facebook, again we pick targeted places where we think the features of Btrfs are really beneficial to the workloads at hand. The big areas we are trying to focus on are system management tasks, the snapshotting type of things. […] The easiest way to describe the infrastructure at Facebook is that it's pretty much all Linux. […]
Chris Mason is the principal author of Btrfs, the open source file system that’s seen as the default file system for SUSE Enterprise Linux. Mason started working on Btrfs at Oracle and then moved to Facebook where he continued to work on the file system as a member of the company’s Linux kernel team. When Facebook has new kernels that need to go out, Mason helps make sure that everything's been properly tested and meets performance needs.
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Olof Johansson

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Harvey, the GPL'ed fork of Plan 9, now runs on the RISCV SPIKE emulator. I'll be trying the lowrisc FPGA bitstream soon. Harvey is C11 compliant and does not use the old Plan 9 C toolchain. We've shown that we can build a working kernel on x86-64 with gcc 4, 5, and 6; and clang 3.5, 3.6 and 3.8. We're looking forward to seeing how Harvey works with the forthcoming RISCV clang port. Both gcc and clang uncovered bugs that had been in the codebase for many years.

We can always use more contributors. For more, see

A distributed operating system. Harvey is an effort to provide a modern, distributed, 64 bit operating system. A different environment for researching and finding new lines of work. It can be built with gcc and clang and has an ANSI/POSIX compliant subsystem.
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Olof Johansson

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What Micah said. Note that there has been some Qualcomm support in the Chrome OS tree for embedded products (whatever the broadband router/firewall/basestation thing is called, for example).

The major difference between embedded and Chromebooks is the graphics stack, and that's an area where Qualcomm hasn't gotten behind upstream development yet. I wish they would some day.
One difficulty is Qualcomm's reluctance to open-source and upstream the various drivers that make up Linux support for the embedded devices. If Qualcomm doesn't demonstrate ongoing support for their devices in the Linux kernel, then Google (or a Chromebook OEM) would best significant engineering risk if an update needs to be made in the future. Qualcomm seems to prefer the business model of Android where they can "ship it and forget it". 
Chrome OS has always been an OS that utilizes multiple SoC’s by multiple manufacturers with various configurations. Amongst those processors, there are a few names missing, though.
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Grant Grundler's profile photoRob Clark's profile photoOlof Johansson's profile photoTomeu Vizoso's profile photo
They are also upstreaming a V4L2 driver for the video codec in the latest chips (the one not from Samsung): - [PATCH v4 0/9] Qualcomm video decoder/encoder driver
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Olof Johansson

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We would like to welcome Chris Lattner, who will join Tesla as our Vice President of Autopilot Software. Chris’ reputation for engineering excellence is well known. He comes to Tesla after 11 years at Apple where he was primarily responsible for creating Swift, the programming language for building apps on Apple platforms and one of the fastest growing languages for doing so on Linux. Prior to Apple, Chris was lead author of the LLVM Compiler Inf...
Alex Buell's profile photo
There's a guy I know who runs a tesla as a taxi locally. Looks the part ;-)
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Olof Johansson

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Registered for ELC in Portland. See you there!
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Looking forward to saying hello again.
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Olof Johansson

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With a conference coming up, it occurred to me to test whether that shiny new Fedora 25/Wayland setup would work with LibreOffice in the two-screen mode. The result is not good; it only draws 1/4 of the frame on the external monitor. I'm sure glad I discovered that here, and not while standing in front of a crowd that is waiting for me to start talking...

I suppose I could quickly redesign all of my slides. Or, more rationally, just use the Xorg fallback mode, which appears to work just fine. But this is a bit disappointing; the Wayland stuff really seemed to be working well, with a minimum of weird glitches, until now.

Has anybody else seen this? Any workarounds?
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Olof Johansson's profile photoJeff Hammond's profile photoDarren Hart's profile photo
+Jeff Hammond it's become a comedy of errors really, but I won't hijack Olof's reshare of Jon's post for an Intel internal rant :-) More on Lync/mail if you like.
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Olof Johansson

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Hm. Is there really no hobbyist board that brings out USB on a pin header? CHIP doesn't, MinnowMax doesn't (well, not on the low-speed header at least). Radxa Rock doesn't have it either. Not SAMA5D3-Xplained either.

Beaglebone falls short due to the limited USB host controller, and it doesn't break them out there.

What else should I look at? Maybe CHIP + external USB will be the way to go here, we'll see.
Geert Uytterhoeven's profile photoMaxime Ripard's profile photoAlexandre Belloni's profile photoOlof Johansson's profile photo
+Alexandre Belloni: Interesting. At 75 EUR for Acqua + Berta-A5-ext it's pushing the cost limits but it's a neat platform.
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Olof Johansson

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Emptying out my office today in anticipation of getting new floors installed in it tomorrow (last room on reflooring project).

Coming across a lot of stuff I should have scrapped a long, long time ago. Refurbished Pentium 4 PC that I bought in 2005 that hasn't been powered on since I moved from Austin in 2010. Two of them, actually.

Some questionable hacking projects that will never see the light of day. A 50cm stack of old laptops. 10/100MBit hubs. A 1st-gen Apple TV. So. much. crap.

I suspect a lot of my old PA Semi hardware will hit the recycling heap this time too. I'll keep one spare board around (+ the one I have in the boot farm).

Things I'm keeping though: The PowerMac 7600 I have under my desk, it's the perfect size for a foot stool when I lean back in my chair. Just opened it to take a look, not a speck of dust inside, and it still has the original 120MHz 604 CPU card. Maybe I'll power it on sometime and install Debian on it.

Big nightmare left to do is take down the board farm and evacuate the closet it's in -- in a manner that I can reassemble the systems again.

When I bring it all back up over the next few weeks, I'm planning on building it a lot more compact. I've specced out and ordered one setup that's using 2020 extruded aluminium to build a cage that slots in plexiglass shelves that will hold the boards, with 1-4 boards per shelf. Should be a lot less messy than what I have now, especially if I get time to build the dedicated power/USB board I have in mind.

Documenting the horrid mess I have now for posterity's sake.

Brief description of what's in there: Two RPC powerstrips along the sides, and one at the top. Underneath the top one is the AMD 1100 system, with a Jetson TX1 next to it, the selves below contain various of the other boards, and a few chromebooks. The two compact shelves were from a semi-abandoned project to put all boards down on a large slab of plexiglass that didn't work from a cable management point of view.

Underneath that is the Tegra2 board that manages the farm, plus the 28-port USB hub that most consoles hang off of. At the bottom a Synology NAS and a Cisco switch. On the floor, under the monitor and keyboard, is a Dell dual Xeon workstation that cranks the builds.
claudio crabini's profile photoJohn Ruble's profile photoOlof Johansson's profile photoHeiko Stübner's profile photo
+Olof Johansson I can see the small foil bag of the Ivar wall mount utilities still on the side shelf element on that cable-nest picture - reminds me of my Ivar things ;-)
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Olof Johansson

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So, we've now (soon) got hardwood floors around the house. Getting rid of carpet is such an upgrade in air quality, it's remarkable.

Anyway, this leads to a follow-on question: Are automatic vacuums such as Roombas actually something that's worth looking at, or are they just expensive novelty items that never really work well enough to rely on?
Ben Pfaff's profile photoronnie sahlberg's profile photoScott “marsroverdriver” Maxwell's profile photoIgor Grinberg's profile photo
We were using roomba for 4-5 years.
Unfortunately, its battery has died and a new one is expensive. My wife wants the roomba back to life badly, so I'm currently trying to assemble some batteries from my old junk as a replacement.
If my wife thinks Roomba really is a great invention and helpful, I bet it is. 
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