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Arnd Bergmann
Works at Linaro
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Arnd Bergmann

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wow
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Geert Uytterhoeven's profile photoArnd Bergmann's profile photoLiang Wang's profile photoThomas Meyer's profile photo
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it was the time I needed to see most of the world (I missed the vulcano lair).
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One of the two presentations I did at ELC 2015 is now available as video. Slides have been public for a while already at http://elinux.org/images/f/f7/Maintaining_a_Large_Kernel_Subsystem.pdf

The other presentation was scheduled at short notice, maybe the video got lost on the way.
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Andreas Nilsson's profile photoDenis Arnaud's profile photo
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I posted half of my y2038 patch series for wider review today, I'm mostly happy with how the patches turned out in the end, but there are so many details to watch out for, and so many different ways in which people have gotten them wrong in the past, so the series ended up too long to post everything at once.

Part 1 of the series does most of the easier system calls. I want to see how it gets received before I post the other part(s), but the link in the introductory mail points to a git tree that has all the other patches as well.
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+Geert Uytterhoeven Well, not sure what you mean. I think building from scratch != rewriting. Just rebuilding a 32-bit platform with a 64-bit time_t should present no real difficulties, until the developers were stupid (but they most likely were).
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+Kevin Hilman​​ showing by far the cutest embedded nonsense hacks at #LFELC.
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+Rob Clark apparently you haven't seen enough of my PM talks to know I always include sleeping animals.  Now you've been warned.
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It's this time of year, the new list is out, by fails to excite. Old x86 machines running Linux get replaced by new x86 machines running Linux. Top 10 almost unchanged. Overall one new Opteron 63xx, one new BlueGene Q, two new Sandy Bridge-E (why?), all other new entrants are Ivy Bridge-E (Xeon E5 26xx v2) or Haswell-E (Xeon E5 26xx v3). Windows down from two to one machines. Unix up one according to the list, but that system seems to actually run Linux as well.
Gigabit ethernet gradually gets replaced by 10 gigabit. Everything else is the same as before.
For the fourth consecutive time, Tianhe-2, a supercomputer developed by China's National University of Defense Technology, has retained its position as the world's No. 1 system with a performance of 33.86 petaflop/s (quadrillions of calculations per second) on the Linpack benchmark, according to ...
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Vladimir Pantelic's profile photoCarsten Otte's profile photoArnd Bergmann's profile photoGeert Uytterhoeven's profile photo
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No more CELL...
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Since a number of people have asked me: I'm not currently in Düsseldorf, but I will be there Wednesday till Friday, attending Plumbers.

Let me know if you want to meet up, especially if you won't be there after Wednesday.
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Sam Ravnborg's profile photoStefan Agner's profile photoHeiko Stübner's profile photoMichal Simek's profile photo
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Good
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Nice looking development board for 64-bit ARM. Looking forward to kernel patches for this one, hopefully shouldn't be too hard to support given all the work that went into the Allwinner sunxi 32-bit platform.
 
去年9月,苹果率先推出了64位的A7处理器,促使各家芯片厂商开始加速向64位布局。国产芯片厂商全志去年年中就曾放出一张产品线路图,上面显示全志将会在2015年Q4推出64位处理器。不过在近日的香港秋季电子展上,全志展台上展示了一款64位的开发板,可以看到开发板上所搭载的64位处理器型号为H64。
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Nils Magnus (L14 Oxycryocrypt)'s profile photoAlex Bennée's profile photoArnd Bergmann's profile photoZhaoxin Xue (Tony)'s profile photo
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Great! But the post only says there is a this thing in the world and nothing else.
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Arnd Bergmann

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How to enable WLAN on Lenovo Yoga 3 1170, #exactsteps  

1. find out that the built-in card is QCA6164 rev 2.1 based, which does not have working firmware available.
2. Look up list of certified WLAN cards, find that Intel AC 3160 is the only card that is supported by both Lenovo and Linux, so order that.
3. Install the card and find that the BIOS blocks it anyway and only allows booting if the card is disabled.
4. Find the chipset register that the BIOS uses to turn off the PCIe port: "FD" in the LPC bridge, described as "When a function is disabled, software must not attempt to re-enable it. A disabled function can only be re-enabled by a platform reset" in the Intel docs.
5. Ignore that advice and  write 0x1350003 to offset 0xfed1f418 in /dev/mem, followed by a PCI host rescan, which makes the device appear.
6. fix two bugs in the ideapad-laptop driver to get software rfkill support to work again (it was broken since 2010), and to get the Yoga 3 1170 model to work (a recent patch already enabled the Yoga 3 Pro).
7. Disassemble the ACPI DSDT to find the third rfkill flag that is still asserted by the embedded controller and not exposed through the driver.
8. Find that writing 0x4d to 0xff0008bb in /dev/mem enables the WLEX bit in the embedded controller and gets the card to work.
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Steven Rostedt's profile photoArnd Bergmann's profile photoAnthony Kavassis's profile photoFausto Ribeiro's profile photo
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Update: the hack for the intel card kept causing problems, but qca6174 support made it into 4.3-rc1 now.
Adriane was still unhappy with the overall experience of the machine and went back to her old Dell E5420, and I suppose I now get to use the Yoga for traveling.
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I tried to understand the design tradeoffs that made the thing so cheap. I haven't seen the SoC details for the R8 yet, but I assume it's a repackaging of the A13 rather than a new chip. You can get the A13+AXP209 combo for under $4 on Aliexpress, so the R8+AXP209 is probably under $2 in quantity. Its main downsides are the lack of SATA and ethernet compared to its big brother the A10.
The upside of that is the board does not need any expensive physical high-speed connectors, aside from the two USB ports. My guess is that the total cost for the wifi+usb solution is actually lower than using 100mbit ethernet once you add in the PHY and connector.
4GB flash is currently the cheapest quantity you can get on the spot market (around $2), so using a 2GB chip or smaller doesn't actually save anything.
512MB DDR3 RAM is actually maxing out the SoC, going to 256MB would save a dollar at spot market prices but make the machine less useful. With an A10 chip, they would be able to use up to 2GB instead.
It's interesting how they used three separate circuit boards: one for the soc+ram+flash, one for the wifi+bt chip and a big board as the carrier. They must be able to shave off a few cents by making the expensive boards small and the big board cheaper this way. This might also just be what they did on the prototype.

[update: as pointed out by +Tsvetan Usunov, the price I was looking at for the SoC is $4 for A13+AXP209, not $2 as I first wrote. The A13 by itself can be found for around $3]
 
The race to the bottom.
Cheaper and more powerful than Raspberry Pi, "Chip" by Next Thing Co. could be the next revolution in single-board computing.
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This looks like the wifi module they are using. I don't think you can get these for much under $3. The $2 price link that was posted for this is bogus.
http://www.ofeixin.com/data/20150108162813187.pdf
RTL8723 has also been reported to have problems with simultaneous Wi-fi and BT use and the BT link dropping.

Module gets you nothing for FCC. It doesn't have antenna on it. Only reason to use that module is if you can't do RF design or Realtek won't sell you chips.
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By popular request, here are the four charts I showed during my #lfelc  presentation, full slides are available on
http://events.linuxfoundation.org/events/embedded-linux-conference/program/slides, and a video should get uploaded soon.
Drive
merged patches by subsystem maintainerSheet1 v3. 1, v3. 2, v3. 3, v3. 4, v3. 5, v3. 6, v3. 7, v3. 8, v3. 9, v3. 10, v3. 11, v3. 12, v3. 13, v3. 14, v3. 15, v3. 16, v3. 17, v3. 18, v3. 19, v4. 0, total dcache-word-accesses efi-vars fengguang fix-unmapped-word-at-a-time jsgf rjwysocki s5r6 safe-dirty-tlb-flush autofs hfsplu...
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John Stultz's profile photoArnd Bergmann's profile photoDrew Fustini (pdp7)'s profile photoBill Xie's profile photo
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+John Stultz​ git log v3.$[$i - 1]..v3.$i --first-parent --merges' to get all pulls that Linus did, followed by some sed magic and manual esiting to extract the maintainer name, and 'git log $c^..$c --oneline | wc -l' to count the commits.
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I did my first post on the Linaro blog, summarizing what to expect from Linux-3.19 on the arm-soc side.
An overview of what was merged into version 3.19 of the Linux kernel through the arm-soc tree
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Hoang Tran's profile photoNicolas Ferre's profile photoRobert Berger's profile photoFredrik Markström's profile photo
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+Ley Foon Tan thanks for reporting. That's what I get for hand-editing the article numbers ;-)
Fixed now and added the third link as well, pointing to the article that +Serge Broslavsky mentions.
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#vlccrashing in Düsseldorf
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Peter Senna Tschudin's profile photoVladimir Pantelic's profile photoSaulius Krasuckas's profile photoChris Dolan's profile photo
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Had one of those last night, a woman trying to take down 6-7 of them on a downtown road
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