[LinuxBIOS] Via EPIA-MII 12000 questions

[Peter Stuge]

On Wed, May 02, 2007 at 12:15:43PM -0300, Martin Portmann wrote:
> I am developing software for a VIA-EPIA-MII 12000 used in a CarPC
> project.

Nice!


> At the moment I am using Fedora as operating system, directfb to
> access the screen and some self developed applications for audio,
> video and mapping. The actual boot-up times are about 20 seconds
> from the 2.5'' IDE drive.

Is that with factory BIOS or LinuxBIOS?


> I would like to boot from a CompactFlash card in order to speed up
> the boot process and get a robuster sytem.

Aye, good plan.


> So I as a newie I have some questions:
> 
> [1] What are the tipical boot up times I can expect (striped down
> linux kernel, minimal startup scripts, no X11)?

I got down to 12-13 seconds before my board died, and still had room
for improvement. My board is only 600MHz so you can probably go
further down.

See http://linuxbios.org/Screenshots for some footage from the
LinuxBIOS Symposium last October.


> [2] If sombody from the community that has the same board (but
> possibly another revision) and gives me an working image to try how
> likely do I end up with a brick?

Not very likely I think. But get extra flash chips, they're cheap,
it's worth the effort to not get stuck with the project.


> [3] Any helps, tips, references to help me (I tried to google but
> did not find a lot, the actual documentation on LinuxBIOS is also
> quite confusing)?

The LinuxBIOS wiki has a lot of good information.

http://linuxbios.org/The_EPIA-M/MII is where I started.

The FAQ also has a lot of good stuff.

As for booting from CF, there are two options if you insist on using
the CF slot and not a CF->IDE adapter.

1. Turn the CF slot into a pure IDE device. Hotplug will not work.
2. Use the CF slot as the PCMCIA slot it is.

They are both a bit finicky to get working properly. For 2 there's a
util/resetcf in the LB source tree which is needed to run after the
bootloader FILO is done with the CF but before Linux tries to init
the PCMCIA slot. Currently it will require a RAM disk, but we should
just add the code in resetcf into FILO instead.

I did have 1 working but prefered the CF->IDE adapter because then
noone would hotplug my rootfs by mistake.

Also make sure to mount the CF readonly. Both to not wear down the
flash unneccessarily and to be fully resistant to sudden power loss.


//Peter