Fw: Re: Documentation [was: new FSF campaign ..]

Peter Stuge stuge-linuxbios at cdy.org
Tue Mar 1 05:05:01 CET 2005

On Tue, Mar 01, 2005 at 12:44:23PM +0100, Peter Karlsson wrote:
> LinuxBIOS (initialises hardware) -> payload (etherboot,OpenBIOS,
> FILO etc.) (-> operating system)?

Exactly right. But with the right flash memory on the mainboard you
can use the operating system (Linux) as payload directly.

> Ok, but that was just an example. Technical jargon explanation is
> still needed to get into linuxbios. For instance:
> http://www.clustermatic.org/pipermail/linuxbios/2003-March/002240.html
> This mail mentions SPD,VID,DID,I2C etc. Does everybody know what
> these mean? To get more people interested in linuxbios one has to
> lower the bars, and technical jargon is a major blocker (at least for
> me).

I'm not sure I agree that the bar must be lowered. Much of the
development going on in LinuxBIOS is _heavily_ technical and spans
across quite a few different architectures. It's not right or useful
to force developers to work and/or communicate below their
capabilities, and certainly not in an open source project. I would
hate it if someone tried to do that to me.

I do believe however, that all the technical prerequisite knowledge
should be listed, so that people can get up-to-speed on their own.
I'll try to work for this and I think that the wiki is a great forum.

> And yes, I do know what i2c is, and I think I know what spd is (ram
> speed?)

SPD is Serial Presence Detect, the name of an I2C bus between the
northbridge and all RAM modules. Each RAM module has an EEPROM with
more or less correct information about how memory initialization code
should set up the memory controller for correct size and optimal
performance. Quite frequently the information is busted. :(

> but vid & did does not ring a bell.

These are short for Vendor ID and Device ID. VID and DID (or PID,
Product ID) are id numbers assigned by organizations such as PCI-SIG
and USBIF to hardware manufacturers allowing software to identify
hardware in a reliable manner. The ids are stored inside the device,
whether it's PCI or USB. Also true for PCMCIA/CardBus.


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