Slashdot Mirror

Not your hard drive - you need to update your kernel. Slack and Fedora may have it in there by default. SuSE will give you the same issue if you don't.

http://www.epiawiki.org/wiki/tiki-index.php?page=E piaHowto

VideoKeg Whitepaper

I wrote this little whitepaper a while back for Amy Zunk to document the function of the VideoKeg/VideoJukebox boxes. Documented here for posterity.

The primary goal of the video keg was to build a reliable video box that was easy to transport with enough space to store 3 days worth of Anime fan-subs.

The secondary goal of the video keg was to make a home PVR system for video playback and time-shifting, along with a video arcade and perhaps a web browser.

The tertiary goal of the video keg was to find an affordable hardware platform so that we could buy 4 of them immmediately to service the primary goal's need for 4 separate video rooms.

For a PVR, the machine neeed to be small, quiet, low-heat, and still fast enough to run the software video player and arcade games.

For portability, we decided to go with a smaller mini-ITX style cube box.

The primary goal suggests redundant drives, but due to the smaller form factor chassis and heat requirements, it was decided that recreating a harddrive should one encounter problems would be a minor task.

Looking at the primary goal, mplayer seemed to suit the need of playing media with a variety of codecs with a minimum of fuss. Easy to script, easy to extend, low overhead, with the ability to normalize audio and clean up dirty videos - mplayer was simply ideal. This lead to the requirement of a ~1Ghz or greater box. The secondary goals would be served as well, though MAME would like a bit more horsepower for some of the more complex emulators.

In the end, we settled on a Chyang Fun Cellbox CF-7989EPIA (1Ghz EPIA-MII 10000) turnkey system with 128M of RAM, a Samsung 160G harddrive, and a DVD-ROM drive.

• The cellbox is a small attractive easy to transport case.
• The EPIA-M comes with builtin audio, video, mpeg playback hardware, and a variety of other goodies for a VERY attractive price.
• The 128M stick was enough to run mplayer with an Xserver with plenty left over for PVR software.
• A 160G harddrive was the sweet spot cost wise at the time of purchase.

Once the boxes arrived, the decision at the time was which distribution to pick. If I'm managing more than one server for a given purpose, I like to use debian for package management. If this were a lone PVR box, I would have probably used Gentoo simply for the EPIA community support toward that end.

Starting off with Debian 3.1 Sarge, it was apparent a number of things needed fixing to get it to work with the embedded hardware.

Step 1, find patches and build a kernel.

Kernel patches

After roaming the net for hours, there really seems to be one good source for the latest in EPIA patches: the EPIA wiki:

http://www.epiawiki.org

The site has more of a Gentoo bent, but the patches work on a vanilla kernel just the same under debian.

CPU Optimizations

While building all packages, it seemed important to pay attention to optimizations to squeeze every last cycle out the 1Ghz processor. To that end, the generally recommended C3 Nehemiah CFLAGS are:

CFLAGS="-march=i686 -msse -mmmx -mfpmath=sse -Os -pipe -fomit-frame-pointer"

If you use gcc 3.3, there is a new arch designation for C3 Nehemiah CPUs:

-march=c3-2

Some in the commmunity think that the small 64k L1 cache on the C3 processors is causing starvation, and using -Os and not -funroll-loops actually helps performance:

CFLAGS="-march=i686 -msse -mmmx -mfpmath=sse -Os -pipe -fomit-frame-pointer"

Many others claim the following works best for them:

Depends. If we're talking about their low-power Nehemiah/Eden class CPUs, some Gentoo people have their own portage tree. I'm looking into this for my next mythbox.

There are also some "positive" things that come out of the VIA -- Like the CLE266 being one of the best-supported video cards by the DirectFB project. That said, I'm actually very, very happy that there are places like the EPIA Wiki to walk you through how to get all of this stuff working on your own distribution instead of being railroaded into using VIA's. Mine runs Freevo on Gentoo, which suits me just peachy.

I'm sure VIA just baked everyone else's Linux patches into a single distribution to roll out with their hardware -- Not that there's anything wrong with that, of course -- But I would undoubtedly have preferred VIA to have spent more time contributing to the success of existing, frequently-used projects (similar to how they did for Xine to get it to run with their mpeg4 acceleration, I guess, although preferrably in a more package-neutral manner) for their hardware than building their own distribution on the backs of all of the fine folks that have worked so hard to make these adorable little boxes go.

The M and MII boards have well documented DMA issues There have been many attempts to contact VIA to discuss these, all have been actively ignored (we are pretty sure they are getting the messages).

What concerns me is that the problem has been fixed in windows, but Via wont even talk to linux people about it. That indicates a certain lack of interest in the linuxworld that bodes badly should problems arise with these new mobos. I would be very circumspect about picking up another mobo from them unless I was sure I wouldn't need support.

Just one jilted dudes opinion.

Lilliput 7" touchscreens are only $279 at www.mp3car.com. Prefect for and undercabinet mounting. Combine that with a mini-itx board and you have a great kiosk or mp3 car player.

Other links of interest:

Linux Touch Screen HOWTO
EPIA HOWTO
Gentoo EPIA HOWTO
Nehemiah Hardware Entropy Generator
VIA PadLock support for Linux

EpiaKernelAbout

Sorry if it's the wrong answer. Just yesterday I thought about installing linux on my M10000 and found this. But I haven't installed linux and applied the patch yet.

Course, having the wrong answer never stopped me from posting on /. before.