Samsung will have big.LITTLE. So what?

Lot of services followed article on EETimes where it was announced that Samsung will present 8-core ARM cpu. What was skipped on some of them is that this is big.LITTLE design so it is made as 4xCortex-A7 + 4xCortex-A15 setup.

Good to know that there will be silicon from other vendors than ARM Ltd. Current development platform is Versatile Express TC2 (Test Chip 2) which shows that amount of A7 cores does not have to match A15 ones (it has 3xA7 + 2xA15).

But amount of cores is one thing. People usually complain about battery life and guess that such setup will suck power like crazy… when it is especially designed to save power.

Take a look at current “war” at mobile market. 2 years ago single core 1GHz Cortex-A8 cpu wit 512MB ram was high end. Then we got dual core cpu (usually Cortex-A9 based like Exynos4, OMAP4, Tegra2) and 512-1024MB of memory. Battery usually had similar capacity and lived similar time. During 2012 we saw move to quad core processors in mobile devices (Exynos4412, Tegra3) with 1-2GB ram. Space for battery was same or smaller. Next year will bring Cortex-A15 cpu (Exynos5, OMAP5, Tegra4) but this eats power…

So phones will probably get big.LITTLE processors to give users with lot of cpu power when needed and battery life otherwise. Cortex-A5/8/9/15 will not disappear from market — will land in normal and cheap devices.

I have dual core Cortex-A15 netbook now (Chromebook) and it works fast. Who knows, maybe in 2014 I will be able to replace it with something powered by 4xA7 + 4xA15 processor (unless ARMv8 will land at same time). And there is a work on getting ALL of cores running at same time…

New thing to buy: Samsung Chromebook

Sometimes it is good to take a look at IRC channel in the evening. There will be new chromebook from Samsung. Someone may say “So what? It’s just yet another chromebook not worth looking at.” but I will disagree.

What is special in this device? Specification of course ;) Exynos5 Dual (5250) which has 2 Cortex-A15 cores, 2GB of memory, 16GB of eMMC (a bit small but 64GB sd cards exist) and all that in 11.6″ netbook case. There is no ARM device on a market which could be compared and run open source operating system.

I hope to get one soon — online stores will sell it on Monday. From what I know there will be a way to run other operating system than ChromeOS — I will switch to Ubuntu or Debian on first day probably.

And finally will replace Efika MX Smartbook.

ARM 64-bit porting for OpenEmbedded

As already I wrote during summer I was working mostly on AArch64 (ARM 64-bit) — especially on OpenEmbedded support.

I spent time on reminding myself how OE works, learning new tricks and creating some limited images (we removed unneeded daemons etc) for our next step which would be booting ARM64 images in Fast Models. Yes, there is no existing hardware yet for this architecture :) But we want to have distributions ready for it when it became available.

Last Monday Linaro published glibc patches for AArch64 port so normal cross compiler works (people already built bare metal one) and work got speed up. During previous week I got opportunity to discuss with ARM Ltd. engineers about internal compiler errors in gcc and got some of them fixed next day. During hacking sessions in Linaro office (in Cambridge, UK) we managed to get most of our targets done:

  • oe-core minimal image
  • oe-core base image
  • on device toolchain
  • meta-toolchain based SDK
  • openssl working
  • libgcrypt ICE got work around
  • meta-aarch64 layer for OE-Core got published

Plans for this week are LAMP image and start merging everything usable back into OpenEmbedded. I do have OpenEmbedded Core branch already and need to create such one for OpenEmbedded.

What interest me in ARM world

When I published my last post about ARM boards there were many questions and suggestions with interesting devices. Thank You all for it.

But there were also suggestions about ARM9 or ARM11 based devices. So I decided that it is good time to write what interest me now in ARM world.

But first some inventory. I had/used/have several devices with ARM cpu:

  • StrongARM (armv4) one:

    • Sharp Zaurus SL-5500 (which took me to ARM world)
  • ARM920 (armv4t) ones:

    • Openmoko GTA01 bv3, bv4 (s3c2410)
    • EDB9301 (EP9301 cpu)
    • Sim-One (EP9307)
  • ARM926 (armv5te) ones:

    • Sharp Zaurus sl-5600 (pxa250)
    • Sharp Zaurus c760/sl-6000 (pxa255)
    • Sharp Zaurus sl-c3000 (pxa272)
    • Sheevaplug (kirkwood)
    • Atmel devboards (at91sam9263, at91sam9m10)
    • ST-Microelectronics/ST-Ericsson NDK-15, NHK-15 (st88n15)
    • Nokia 770 (omap1710)
    • Linksys NSLU2 (ixp425 iirc)
  • ARM1136 (armv6) ones:

    • Nokia N810 (omap2430)
    • Bug r1.0, r1.2 (i.mx31)
  • Cortex-A8 (armv7a) ones:

    • Beagleboard B7, B7, C3 (omap3430)
    • Nokia N900 (omap3430)
    • Nexus S (exynos3)
    • Genesi Efika MX Smartbook (i.mx51)
    • Freescale Quickstart (i.mx53)
  • Cortex-A9 (armv7a) ones:

    • Pandaboard EA1, A1 (omap4430)
    • Archos G9 80 (omap4430)

All of that during last 8 years. Most of my ARM live so far was around ARM926 based devices (some of them still can not be listed here) and I do not want to go there again. Kirkwood core was fastest one with 1.2GHz clock and 512MB of RAM it was really fast machine. I only missed Serial ATA in my Sheevaplug (rev 1.0) but even with hard drive on USB it was nice improvement.

Then I played a bit with ARM11 processors. Ok, they were faster than most of ARM9 cpus but I already had experience with Sheevaplug. And after few months first Cortex-a8 board landed on my desk — I got Beagleboard B7 from Bug labs as test platform for their new device. This was improvement!

I still remember my reaction when connected it to normal LCD monitor and saw it used at 720p resolution (1680×1050 was a bit hard for omap3). Moved to Nokia N900 few months later and found that fast cpu means nothing when paired with slow storage and not enough memory for system.

So today I prefer to not look below Cortex-A9 (or comparable cores like ones from Qualcomm or Marvell). Hope to play one day with Cortex-A5 (which should replace ARM926 one day) just to see how low-end armv7a cpu behave.

And wait for ARMv8 to hit market.

Let’s take a look at ARM boards again

Over year ago I wrote post in which I complained about cheap developer boards but concentrated on ones supported by Linaro. This time I want to write about boards which I did not even had occasion to play with.

Most popular one was Rasperry/Pi. But as I already wrote why I’m tired of it I prefer to not discuss it too much. In short: old cpu core (ARM11), not enough memory (256MB), requires closed binaries even to boot (the GPU binary also contains the first stage bootloader).

Then we have a lot of boards based on AllWinner A10/A13 cpus. Single core Cortex-A8, no Linux kernel support in mainline. Fun is that there is Serial ATA controller in SoC but most of the boards does not offer that so users have to use SD or USB storage which is slower. Example devices: Hackberry, Cubieboard, Mele A1000.

Fun stuff starts to appear from Freescale area. i.MX6 cpu has potential and many options available. There are Wandboard, Sabrelite with second one providing interesting addons like mini PCI-Express slot (with PCIe signals) or small board with buttons (Android oriented).

Quad A9 boards are also available with Samsung s3c4412 cpu — like ODroid-X which I described when it was released. But no Serial-ATA in this processor.

So which one to choose? All depends what you want to do with it. Few days ago on debian-arm mailing list someone asked “Workstation based on ARM motherboard, good idea ?” which got me to conclusion that it possible to setup low specification desktop today with ARM cpu.

I wonder how much would I have to pay for mini-ITX compatible board (can be smaller but has to be mountable to normal PC case) with 2-4GB of memory (SO-DIMM preferred) with quad core cpu and Serial ATA. So I could connect usb mouse/keyboard, monitor though HDMI, speakers with 3.5mm jack, Ethernet (1GbE preferred) and boot Debian/Ubuntu straight from SATA hard drive or ssd. 2D/3D acceleration working and recent (max 2 versions old) Linux kernel working with not insane amount of patches. But such day probably will not happen.

UPDATE: Looks like VIA had such idea with their APC board. Neo-ITX format but components few years old ;(

Switched blog theme again

Long, long time passed since last time I changed theme on my blog. What you see this time is Twenty Twelve from WordPress team. Maybe it is not yet finished but it works better than Carrington which I had before. Not to mention that previous theme was not updated for long time (I did few updates by hand with code from their Subversion repository but it was not comfortable).

This theme looks good on desktop, phone, tablet and I will use it for probably quite long time. Will update it to released version once there will be such one ;D