[libreplanet-discuss] Fully free $100 ARM PCs to be a possibility ? (Writing GNU/Linux drivers is needed)

[Alexey Eromenko]

Hi All,

As you might know, there is an onslaught of cheap ARM, Chinese-based
chips, which until now I have not considered seriously for use in a
desktop PCs.

One particular chip, that fell into my attention is the Allwinner A10
SoC, and it's contents:

ARM CPU Cortex A8 @ 1 GHz
ARM Chipset
VPU - Cedarx - hardware video decoder 2160p Super HD :
H.263/H.264/MPEG4-AVC/MPEG2/DVD/VC-1/WebM/VP8/... (plays Free Software
codec: WebM/VP8 !)
ARM Mali-400 - 3D accelerator GPU.
SATA2 controller
Memory controller, DDR3
USB 2.0 controller
Audio controller, AC'97
Fast Ethernet 10/100 controller

All of above are just logic inside the one physical chip ! This level
of integration is unheard-of in the Intel PC world.
Guess how much this wonder-piece costs in China ? $7 in bulk !

Performance:
According to 3rd party benchmarks, the A10 chip comes close to Intel
Atom in performance.
It has enough horse-power to run a full desktop distro, like Ubuntu,
along with some heavy programs, including OpenOffice and GIMP image
editor.
Such cheap SoCs gives an opportunity to attack the very low-end of the
PC market and build ultra-cheap GNU/Linux PCs.

What works ?

Current drivers for GNU/Linux OS are very basic: network, USB and
basic 2D X11 works.
Video of Ubuntu running on the Allwinner A10 chip, Gooseberry:
http://www.youtube.com/watch?feature=player_embedded&v=SFQc6WnEQFw

What does not work ?

Audio driver
VPU (hardware video decoder)
3D graphics - LIMA driver is a reverse-engineer effort to build free
3D driver for Mali-400 GPU, incomplete.
NOTE: All the drivers are available for the Android O.S.

Why ARM ?

I know that Richard Stallman himself uses MIPS-based Lemote desktops
and laptops, but after reviewing this I rejected it on
price/performance grounds. $400 for an ultra-low-end Lemote laptop is
just way too expensive.
Chinese ARM manufacturers are doing the job in the $100-$150 price
range, or x3 to x4 times cheaper than Lemote.
The idea of $100 ARM PCs and laptops is incredibly great one, and
could widen the reach of Free Operating systems well beyond the reach
of Wintel (MS-Windows + Intel) coalition.
By comparison, Intel Atom CPU costs ~$50 + ~$20 for chipset, which
brings the minimum price to $70, or x10-times above the A10 SoC price.
Such prices are very appealing to the wider audience.
According to rhombus-tech, the Allwinner A10 SoC gives "the highest
bang-per-buck ratio of any SoCs available".
http://rhombus-tech.net/allwinner_a10/
In addition, the A10 enjoys huge popularity in China with dozens of
devices based on it.

Why hardware video decoder ?

Intel Atom class CPU was tested by me, and found not adequate to run
WebM video in Full HD quality. The video stucks every few seconds.
Your ARM-based CPU is probably even weaker than the Atom.
This is not a problem at all for serious CPU, such as Intel Core i3,
as it can render WebM @ Full HD 1080p happily without hardware video
decoders. -- no drivers for hardware video decoder are needed for Core i3 !

Without those video decoder drivers, the A10 CPU is not powerful
enough to run HD video in software. The lack of GNU/Linux video drivers
will limit the use-cases to low-quality video 240p and to Office work
on Allwinner A10-based GNU/Linux PCs.
(Can Lemote play WebM video in HD quality 1080p ?)

================
What can be done ?
================
Allwinner tech seems to be Free-Software-friendly, and they seem to
provide hardware specs and other documentation along with library
needed to develop the drivers.

The VPU has a cedarx library, so the main difficulty is developing a
bridge between cedarx API and the various GNU/Linux media players, HTML5
browsers and media frameworks.
HTML5 browsers are, in fact, HD video players. (due to HTML5 video)

GNU/Linux has lots of components, that may require patching:
-Chromium browser
-FFox browser
-libva
-libvpx (VP8/WebM codec library)
-ffmpeg
-libavcodec
-xine
-gstreamer
-KDE phonon
-VLC
...
You can ask Allwinner people (Tom Cubie) to provide you cedarx library
and docs, so you could start working.
Mali-400 GPU is irrelevant for video decoding, as it only does 3D GFX.

Also drivers for 2D / Xorg (hardware cursor, ...) could help and audio
driver is a must.

I'm not a pro developer, but a professional BETA tester, so I could
help you with QA later down the road.

Finally I came up with a list of cheap Allwinner A10-based devices,
that caught my eye, and may help fellow Free Software developers:

Tablet convertible with attached keyboard to Netbook 7":
http://www.aliexpress.com/product-fm/550631962-DVC-Q720-5Points-Touch-Capacitive-Screen-2160P-Video-Android4-0-ICS-1GB-RAM-8GB-Storage-Enhanced-wholesalers.html
http://www.aliexpress.com/fm-store/109505/211352415-532912203/USB-Keyboard-Leather-Cover-Case-Bag-for-7-Tablet-PC.html

Netbook on А10:
http://www.aliexpress.com/product-gs/577959246-first-10inch-netbooks-come-with-AllWinner-A10-CPU-512MB-RAM-4GB-storage-android-4-0-OS-wholesalers.html

A10-based MK802 - mini PC, USB sized, 1GHz CPU + 1 GB RAM:
http://www.aliexpress.com/product-fm/574126655-Android-4-0-Mini-PC-IPTV-Google-TV-Smart-Android-Box-Allwinner-A10-MK802-wholesalers.html

A10-based Mele A1000 - TV-PC:
It has a wide range of I/O ports, which could prove useful.

A project, similar to the Raspberry Pi, but based on the A10 chip.
Gooseberry dev board:
http://gooseberry.atspace.co.uk/

I really hope to see a $100 laptop/tablet/PC a reality within few years time.

Best wishes,
-- 
-Alexey Eromenko "Technologov"