Tag Archives: laptop

ARMology

When last time I was in Cambridge we had a discussion about ARM processors. Paweł used term “ARMology” then. And with recent announcement of Cortex-A12 cpu core I thought that it may be a good idea to write a blog post about it.

Please note that my knowledge of ARM processors started in 2003 so I can make mistakes in everything older. Tried to understand articles about old times but sometimes they do not keep one version of story.

Ancient times

ARM1 got released in 1985 as CPU add-on to BBC Micro manufactured by Acorn Computers Ltd. as result of few years of research work. They wanted to have new processor to replace ageing 6502 used in BBC Micro and Acorn Electron and none of existing ones did not fit their requirements. Note that it was not market product but rather development tool made available for selected users.

But it was ARM2 which landed in new computers — Acorn Archimedes (1987 year). Had multiply instructions added so new version of instruction set was created: ARMv2. Just 8MHz clock but remember that it was first computer with new CPU…

Then ARM3 came — with cache controller integrated and 25MHz clock. ISA was bumped to ARMv2a due to SWP instruction added. And it was released in another Acorn computer: A5000. This was also used in Acorn A4 which was first ARM powered laptop (but term “ARM Powered” was created few years later). I hope that one day I will be able to play with all those old machines…

There was also ARM250 processor with ARMv2a instruction set like in ARM3 but no cache controller. But it is worth mentioning as it can be seen as first SoC due to ARM, MEMC, VIDC, IOC chips integrated in one piece of silicon. This allowed to create budget versions of computers.

ARM Ltd.

In 1990 Acorn, Apple and VLSI co-founded Advanced RISC Machines Ltd. company which took over research and development of ARM processors. Their business model was simple: “we work on cpu cores and other companies pay us license costs to make chips”.

Their first cpu was ARM60 with new instruction set: ARMv3. It had 32bit address space (compared to 26bit in older versions), was endian agnostic (so both big and little endian was possible) and there were other improvements.

Please note lack of ARM4 and ARM5 processors. I heard some rumours about that but will not repeat them here as some of them just do not fit when compared against facts.

ARM610 was powering Apple Newton PDA and first Acorn RiscPC machines where it was replaced by ARM710 (still ARMv3 instruction set but ~30% faster).

First licensees

You can create new processor cores but someone has to buy them and manufacture… In 1992 GEC Plessey and Sharp licensed ARM technology, next year added Cirrus Logic and Texas Instruments, then AKM (Asahi Kasei Microsystems) and Samsung joined in 1994 and then others…

From that list I recognize only Cirrus Logic (used their crazy EP93xx family), TI and Samsung as vendors of processors ;D

Thumb

One of next cpu cores was ARM7TDMI (Thumb+Debug+Multiplier+ICE) which added new instruction set: Thumb.

The Thumb instructions were not only to improve code density, but also to bring the power of the ARM into cheaper devices which may primarily only have a 16 bit datapath on the circuit board (for 32 bit paths are costlier). When in Thumb mode, the processor executes Thumb instructions. While most of these instructions directly map onto normal ARM instructions, the space saving is by reducing the number of options and possibilities available — for example, conditional execution is lost, only branches can be conditional. Fewer registers can be directly accessed in many instructions, etc. However, given all of this, good Thumb code can perform extremely well in a 16 bit world (as each instruction is a 16 bit entity and can be loaded directly).

ARM7TDMI landed nearly everywhere – MP3 players, cell phones, microwaves and any place where microcontroller could be used. I heard that few years ago half of ARM Ltd. income was from license costs of this cpu core…

ARM7

But ARM7 did not ended at ARM7TDMI… There was ARM7EJ-S core which used ARMv5TE instruction set and also ARM720T and ARM740T with ARMv4T. You can run Linux on Cirrus Logic CLPS711x/EP721x/EP731x ones ;)

According to ARM Ltd. page about ARM7 the ARM7 family is the world’s most widely used 32-bit embedded processor family, with more than 170 silicon licensees and over 10 Billion units shipped since its introduction in 1994.

ARM8

I heard that ARM8 is one of those things you should not ask ARM Ltd. people about. Nothing strange when you look at history…

ARM810 processor made use of ARMv4 instruction set and had 72MHz clock. At same time DEC released StrongARM with 200MHz clock… 1996 was definitively year of StrongARM.

In 2004 I bought my first Linux/ARM powered device: Sharp Zaurus SL-5500.

ARM9

Ah ARM9… this was huge family of processor cores…

ARM moved from a von Neumann architecture (Princeton architecture) to a Harvard architecture with separate instruction and data buses (and caches), significantly increasing its potential speed.

There were two different instruction sets used in this family: ARMv4T and ARMv5TE. Also some kind of Java support was added in the latter one but who knows how to use it — ARM keeps details of Jazelle behind doors which can be open only with huge amount of money.

ARMv4T

Here we have ARM9TDMI, ARM920T, ARM922T, ARM925T and ARM940T cores. I mostly saw 920T one in far too many chips.

My collection includes:

  • ep93xx from Cirrus Logic (with their sick VFP unit)
  • omap1510 from Texas Instruments
  • s3c2410 from Samsung (note that some s3c2xxx processors are ARMv5T)

ARMv5T

Note: by ARMv5T I mean every cpu never mind which extensions it has built-in (Enhanced DSP, Jazelle etc).

I consider this one to be most popular one (probably after ARM7TDMI). Countless companies had own processors based on those cores (mostly on ARM926EJ-S one). You can get them even in QFP form so hand soldering is possible. CPU frequency goes over 1GHz with Kirkwood cores from Marvell.

In my collection I have:

  • at91sam9263 from Atmel
  • pxa255 from Intel
  • st88n15 from ST Microelectronics

Had also at91sam9m10, Kirkwood based Sheevaplug and ixp425 based NSLU2 but they found new home.

ARM10

Another quiet moment in ARM history. ARM1020E, ARM1022E, ARM1026EJ-S cores existed but did not looked popular.

UPDATE: Conexant uses ARM10 core in their next generation DSL CPE systems such as bridge/routers, wireless DSL routers and DSL VoIP IADs.

ARM11

Released in 2002 as four new cores: ARM1136J, ARM1156T2, ARM1176JZ and ARM11 MPCore. Several improvements over ARM9 family including optional VFP unit. New instruction set: ARMv6 (and ARMv6K extensions). There was also Thumb2 support in arm1156 core (but I do not know did someone made chips with it). arm1176 core got TrustZone support.

I have:

  • omap2430 from Texas Instruments
  • i.mx35 from Freescale

Currently most popular chip with this family is BCM2835 GPU which got arm1136 cpu core on die because there was some space left and none of Cortex-A processor core fit there.

Cortex

New family of processor cores was announced in 2004 with Cortex-M3 as first cpu. There are three branches:

  • Aplication
  • Realtime
  • Microcontroller

All of them (with exception of Cortex-M0 which is ARMv6) use new instruction sets: ARMv7 and Thumb-2 (some from R/M lines are Thumb-2 only). Several cpu modules were announced (some with newer cores):

  • NEON for SIMD operations
  • VFP3 and VFP4
  • Jazelle RCT (aka ThumbEE).
  • LPAE for more then 4GB ram support (Cortex A7/12/15)
  • virtualization support (A7/12/15)
  • big.LITTLE
  • TrustZone

I will not cover R/M lines as did not played with them.

Cortex-A8

Announced in 2006 single core ARMv7a processor core. Released in chips by Texas Instruments, Samsung, Allwinner, Apple, Freescale, Rockchip and probably few others.

Has higher clocks than ARM11 cores and achieves roughly twice the instructions executed per clock cycle due to dual-issue superscalar design.

So far collected:

  • am3358 from Texas Instruments
  • i.mx515 from Freescale
  • omap3530 from Texas Instruments

Cortex-A9

First multiple core design in Cortex family. Allows up to 4 cores in one processor. Announced in 2007. Looks like most of companies which had previous cores licensed also this one but there were also new vendors.

There are also single core Cortex-A9 processors on a market.

I have products based on omap4430 from Texas Instruments and Tegra3 from NVidia.

Cortex-A5

Announced around the end of 2009 (I remember discussion about something new from ARM with someone at ELC/E). Up to 4 cores, mostly for use in all designs where ARM9 and ARM11 cores were used. In other words new low-end cpu with modern instruction set.

Cortex-A15

The fastest (so far) core in ARMv7a part of Cortex family. Up to 4 cores. Announced in 2010 and expanded ARM line with several new things:

  • 40-bit LPAE which extends address range to 1TB (but 32-bit per process)
  • VFPv4
  • Hardware virtualization support
  • TrustZone security extensions

I have Chromebook with Exynos5250 cpu and have to admit that it is best device for ARM software development. Fast, portable and hackable.

Cortex-A7

Announced in 2011. Younger brother of Cortex-A15 design. Slower but eats much less power.

Cortex-A12

Announced in 2013 as modern replacement for Cortex-A9 designs. Has everything from Cortex-A15/A7 and is ~40% faster than Cortex-A9 at same clock frequency. No chips on a market yet.

big.LITTLE

That’s interesting part which was announced in 2011. It is not new core but combination of them. Vendor can mix Cortex-A7/12/15 cores to have kind of dual-multicore processor which runs different cores for different needs. For example normal operation on A7 to save energy but go up for A15 when more processing power is needed. And amount of cores in each of them does not even have to match.

It is also possible to make use of all cores all together which may result in 8-core ARM processor scheduling tasks on different cpu cores.

There are few implementations already: ARM TC2 testing platform, HiSilicon K3V3, Samsung Exynos 5 Octa and Renesas Mobile MP6530 were announced. They differ in amount of cores but all (except TC2) use the same amount of A7/A15 cores.

ARMv8

In 2011 ARM announced new 64-bit architecture called AArch64. There will be two cores: Cortex-A53 and Cortex-A57 and big.LITTLE combination will be possible as well.

Lot of things got changed here. VFP and NEON are parts of standard. Lot of work went into making sure that all designs will not be so fragmented like 32-bit architecture is.

I worked on AArch64 bootstrapping in OpenEmbedded build system and did also porting of several applications.

Hope to see hardware in 2014 with possibility to play with it to check how it will play compared to current systems.

Other designs

ARM Ltd. is not the only company which releases new cpu cores. That’s due to fact that there are few types of license you can buy. Most vendors just buy licence for existing core and make use of it in their designs. But some companies (Intel, Marvell, Qualcomm, Microsoft, Apple, Faraday and others) paid for ‘architectural license’ which allows to design own cores.

XScale

Probably oldest one was StrongARM made by DEC, later sold to Intel where it was used as a base for XScale family with ARMv5TEJ instruction set. Later IWMMXT got added in PXA27x line.

In 2006 Intel sold whole ARM line to Marvell which released newer processor lines and later moved to own designs.

There were few lines in this family:

  • Application Processors (with the prefix PXA).
  • I/O Processors (with the prefix IOP)
  • Network Processors (with the prefix IXP)
  • Control Plane Processors (with the prefix IXC).
  • Consumer Electronics Processors (with the prefix CE).

One day I will undust my Sharp Zaurus c760 just to check how recent kernels work on PXA255 ;D

Marvell

Their Feroceon/PJ1/PJ4 cores were independent ARMv5TE implementations. Feroceon was Marvell’s own ARM9 compatible CPU in Kirkwood and others, while PJ1 was based on that and replaced XScale in later PXA chips. PJ4 is the ARMv7 compatible version used in all modern Marvell designs, both the embedded and the PXA side.

Qualcomm

Company known mostly from wireless networks (GSM/CDMA/3G) released first ARM based processors in 2007. First ones were based on ARM11 core (ARMv6 instruction set) and in next year also ARMv7a were available. Their high-end designs (Scorpion and Krait) are similar to Cortex family but have different performance. Company also has Cortex-A5 and A7 in low-end products.

Nexus 4 uses Snapdragon S4 Pro and I also have S4 Plus based Snapdragon development board.

Faraday

Faraday Technology Corporation released own processors which used ARMv4 instruction set (ARMv5TE in newer cores). They were FA510, FA526, FA626 for v4 and FA606TE, FA626TE, FMP626TE and FA726TE for v5te. Note that FMP626TE is dual core!

They also have license for Cortex-A5 and A9 cores.

Project Denver

Quoting Wikipedia article about Project Denver:

Project Denver is an ARM architecture CPU being designed by Nvidia, targeted at personal computers, servers, and supercomputers. The CPU package will include an Nvidia GPU on-chip.

The existence of Project Denver was revealed at the 2011 Consumer Electronics Show. In a March 4, 2011 Q&A article CEO Jen-Hsun Huang revealed that Project Denver is a five year 64-bit ARM architecture CPU development on which hundreds of engineers had already worked for three and half years and which also has 32-bit ARM architecture backward compatibility.

The Project Denver CPU may internally translate the ARM instructions to an internal instruction set, using firmware in the CPU.

X-Gene

AppliedMicro announced that they will release AArch64 processors based on own cores.

Final note

If you spotted any mistakes please write in comments and I will do my best to fix them. If you have something interesting to add also please do a comment.

I used several sources to collect data for this post. Wikipedia articles helped me with details about Acorn products and ARM listings. ARM infocenter provided other information. Dates were taken from Wikipedia or ARM Company Milestones page. Ancient times part based on The ARM Family and The history of the ARM CPU articles. The history of the ARM architecture was interesting and helpful as well.

Please do not copy this article without providing author information. Took me quite long time to finish it.

Changelog

8 June evening

Thanks to notes from Arnd Bergmann I did some changes:

  • added ARM7, Marvell, Faraday, Project Denver, X-Gene sections
  • fixed Cortex-A5 to be up to 4 cores instead of single.
  • mentioned Conexant in ARM10 section.
  • improved Qualcomm section to mention which cores are original ARM ones, which are modified.

David Alan Gilbert mentioned that ARM1 was not freely available on a market. Added note about it.

My wife has a new laptop

Few days ago was my wife’s birthday. As a gift I gave her new laptop — Acer Aspire One 722. With last released version of Ubuntu on it (with XFCE desktop).

As I got device two weeks earlier I had some time to play with it and do setup. Installed full XFCE desktop (xubuntu-desktop), LibreOffice, XBMC with set of plugins for Polish VOD services, VLC etc. No games as requested. Firefox + Thunderbird as default browser and MUA.

And then there was a day. I gave Ania laptop box with some Belgium chocolates inside (instead of computer) and when we stopped laughing I gave her new notebook in useful case. After coffee I started to migrate her configuration from Dell D400 she used before (with Microsoft Windows XP). Firefox, Thunderbird, OpenOffice and then documents etc. Easy stuff.

Configuration phase was funny — I connected our printer/scanner and before I found where to add printer I got notification “EPSON Stylus DX4000 printer configured”. OK, so maybe scanner needs configuration… Nope — Simple Scan just started scanning instead of complaining (which it did when I bought it few years ago).

Connected netbook to TV and Meta-p gave me choice which display I want to run on (my 42″ Panasonic does not like 1366×768 so cloning does not work).

There are few things which I still have to find out:

  1. How to remove “something has crashed” notifications. My wife will rather not report bugs directly.
  2. How to make audio switching automatically to HDMI when on cable insertion.
  3. How to make internal microphone working.

But other than those I did not have problems. And it is a strange feeling when you take new device, boot Linux on it and it just works.

I did not finished with Chromebook

Some time passed since my earlier post. I had to think about few things and made some decisions.

I will write an installation instruction for Samsung Chromebook users — about installing other operating system on internal storage. Targeted at advanced users but with more or less exact steps. If you do not know how to enable “developer” mode in Chromium then sorry…

And in meantime I worked on packaging. Few minutes ago I pushed kernel to my PPA and once it get built I will offer it in Chromebook hackers PPA so users will be able to use it instead of Chromium OS one. It will need signing and putting on proper partition but, like I wrote above, my packages are not only for novice level users.

Thanks to work started by Antonio Terceiro we have preliminary version of vboot utilities package. I cleaned it a bit and got to state when “cgpt” and “vbutil_kernel” are provided so playing with partitioning will not need files from Chromium OS. Will upload it into PPA as well.

Left speaker in my Chromebook died totally so I decided to spend some time on getting UCM profiles available in “quantal” and “precise” releases of Ubuntu as well. SRU process in progress…

Also got 32GB microSD card so one step closer to having other distributions running. Thinking of Debian here of course. But it is in deep freeze now so harder to get new packages there.

How can you help? Test, file bugs, attach fixes to bugs. And can also replace speaker in my Chromebook so I will not have to use headphones ;D

How to fry speakers in your Chromebook

Lot of people asked me how I managed to fry left speaker in my Chromebook. There are also few which said that it is Ubuntu fault.

So today I used recovery to wipe out my installation of Ubuntu from device and decided to check under Chromium OS. And yes, I got nice smell of burnt plastic etc coming from left speaker area.

Why? Because it is kernel bug. Not Ubuntu, ALSA or user. Ok, it is a bit of user’s fault cause you should not have to play with ALSA mixer. But you can — all binaries are part of Chromium OS stable.

So let me give you needed steps:

  1. Boot Samsung Chromebook (ARM one) to Chromium OS
  2. Login or use guest session
  3. Run terminal (Ctrl+Alt+t)
  4. Run “alsamixer -c0″
  5. Set “Lineout” to highest value
  6. Unmute everything what starts with “Left” or “Right” (depends which speaker you do not like)
  7. Touch speakers (but better not for long)
  8. Hold “Power” button to shut down before it will burn though your desk.

In normal situation I would assume that sound driver will take care of combinations which may break your hardware. But looks like Chromebook developers did had such idea.

Is this howto useful? I think it is. Cause if you have device broken in some way and you want to get it replaced you can just run it and hope for replacement instead of repair.

And when next time someone will write me “go and fix ubuntu rather than putting blame on samsung. Its Ubuntu which is the cause” like I got in recent comment I will just ban such person from commenting.

I am running out of names for computers

Somewhere in 2010/11 I decided to clean up mess of naming machines at home and decided to go with character names from “Winnie the Pooh” books (Polish edition). Today I got new developer board and had to spend a moment to get a name for it.

So “klapouchy” (Eyeore) will be new name for DragonBoard. Maybe not best one but most of the names are already taken:

  • krzys (Christopher Robin) is my router (because Chris decides who can enter Hundred Acre Wood which is the name of my WiFi network)
  • puchatek (Winnie the Pooh) is main desktop
  • lumpek (Lumpy) is conference laptop (it was lucek before because it got Ubuntu Lucid as first system)
  • gofer (Gopher) is Efika MX Smartbook
  • krolik (Rabbit) is Samsung Chromebook
  • malenstwo (Roo) is Pandaboard (there were malenstwo-a1 and malenstwo-ea1 when I had two boards)
  • prosiaczek (Piglet) was MX53 Quickstart
  • kangurzyca (Kanga) is my wife laptop (she chosen the name)
  • sowa (Owl) is another router
  • tygrysek (Tigger) is my VPS (at beginning it was up/down/up/down all the time)

So most of the names from books are already taken. There are also Disney movies which adds few new ones (like Gopher and Lumpy) and cartoons (which I am not fan of). In worst case one day I will start re-using names or add names from other story.

What I used before? Desktop was “home” or “hrw”, Dell laptop (now “kangurzyca”) was “maluch” (small) due to 12″ size, “lumpek” was “lucek” due to Ubuntu Lucid installed and rest was named by hardware name (which is a default in OpenEmbedded).

How you are naming your machines?

Let’s compare some cpu ;)

When I bought Samsung Chromebook friend started “nbench” on it. So I did same on my conference laptop. None of devices won…

Idea of testing cpu power was sitting somewhere at back of my head and finally I decided to just run one simple command available on nearly every GNU/Linux based system: “openssl speed”. Sure, on some systems it will use hardware accelerators, on others (or not) some options enabled to get more speed (like ARM assembly version which is not enabled in Debian/Ubuntu systems). But it is something what anyone can run at home.

Table may be hard to decipher so I also give it as Google Docs. It also has few more devices listed and whole tables (one below is for 8192 size samples).

Devices in table are:

  • my Intel Core i7-2600K desktop
  • my Intel U7300 (ultra low voltage) conference laptop
  • Exynos5 Dual powered Samsung ARM Chromebook
  • Exynos4 Dual powered Tizen development platform (got rid of it today)
  • i.mx515 powered Efika MX Smartbook
  • Beaglebone with AM335x cpu
  • Sheevaplug (as only armv5te device which can compare with other entries)

Devices were running different versions of OpenSSL under different systems. It is listed in Google Docs document.

CPUCore i7U7300Exynos 5250Exynos 4210i.mx515AM335xFeroceon 88FR131
Architecturex86-64x86-64armv7a (a15)armv7a (a9)armv7a (a8)armv7a (a8)armv5te
MHz34001300170010008007201200
OpenSSL version1.0.1c1.0.1c1.0.1c1.0.0f1.0.1a1.0.0i1.0.0d
 
md41111896393198328471205906143746103068119367
md5693969249301224040148089854015336586518
hmac(md5)686511248859225839149153867285498187651
sha172152822277014773971233495253544638123
rmd1602474539350010693557790401882631830803
rc489461522566015394986829637702936445036
des cbc737032719137811212991496686018829
des ede32809110578141837806552630053130
seed cbc78204311813900224361176501167113087
rc2 cbc4432713839236911549410897739310699
blowfish cbc133455520044947137540235361565420584
cast cbc118852491625532631738228481529820590
aes-128 cbc127378959556536022386164771087611697
aes-192 cbc1061418100255973186531391292219968
aes-256 cbc904876914848564164191209179818677
camellia-128187958444035869815447233251550714197
camellia-192141346331804586712090183001226111138
camellia-256141422332724592712050183831224711131
sha256216766867916433423427181481202213040
sha512336729135935311268877532124843221
whirlpool12121147920278204602384022623085
aes-128 ige122085430186321822126155901046911219
aes-192 ige1021333610754269186961335589049647
aes-256 ige875143100147636163071163577358433
ghash19386091680343547912136

Most interesting columns are U7300 and Exynos 5250 ones — 3 years old laptop which I bought for conferences compared to Chromebook. Looks like for next conferences/events I will rather go with Chromebook not UL30A. This will give me one or two hours of battery life less but it is much lighter device at same time. But have to test it first for few days to check is it comfortable enough for daily use.

Used Chromebook for few days

Some days ago I got Chromebook and have to say that device is amazing. Light, small and fast enough for conference laptop. During Linaro Connect I did some hacking on it with help from Olof Johansson and Andrew Wafaa (he brought Chromebook for me from Cambridge). I also used script from Jay Lee to get all information required to resize STATE partition and fit Ubuntu on internal storage.

Now I am running Ubuntu ‘raring’ on my Chromebook with XFCE as a desktop — all running from internal storage (16GB eMMC from SanDisk). So far I did not remove original Chromium from device as I keep it as a reference system to be able to compare what I got with how it works with system from Google.

So what works? Most of things — suspend/resume, wifi, bluetooth, sound, touchpad, usb ports, sd storage, camera. But why they should not work when I am using same kernel binary as Chromium OS does ;) So far did not yet came to rebuilding kernel — there were more important things to do first.

During Wednesday hacking evening I updated xf86-video-armsoc driver to X11 ABI 13 used by packages in ‘raring’ so I got 2D accelerated environment. Tried to find all sources required to build xf86-input-cmt driver but then got hint from Olof that “evdev” driver is enough — all it needs is small snippet of X11 configuration. And yes — it works but is not precise. Andrew told that he will try to build “cmt” driver for OpenSUSE so we will know how better it is.

What next? I have to create package for “cgpt” (GPT manipulation tool with support for Chromium OS extensions), tools and keys needed to sign kernel and kernel itself. Then some work would be needed for OpenGLES stuff but this can wait. I plan to upload everything needed into Debian and then request syncs to Ubuntu. From yesterday’s discussions I know which mailing lists I should go.

But I do not plan to cover everything. There will be no installation support from me. Users have to do it on their own cause there are several ways of getting other operating systems on Chromebook:

  • boot from SD card
  • boot from USB storage
  • resizing STATE partition to put system on internal eMMC (I did that)
  • removing Chromium OS completely to get more space for own system

Then there are also systems when user has developer firmware installed (that’s different that developer mode) or even setup where normal U-Boot is used as bootloader.