Jan Kok wrote:

> 
> - I'm looking for some consistent terminology to describe the various
> sections of the LinuxBIOS code, and some precise definitions of the terms
> (where the boundaries between the sections are).  I've seen stage 1, stage
> 2, stage 3, bootstrap, payload, IPL and SPL.  Any suggestions about what the
> preferred terms are, and what the definitions should be?
> 


IPL and SPL are terms invented by M-Systems and somewhat DiskOnChip
specific. IPL means Initial Program Loader and SPL means Secondary
Program Loader. We need these two Program Loaders due to some
limitation of DiskOnChip. DiskOnChip is made with NAND Flash which
does not support random access in contract to NOR Flash used in
traditional BIOS. In order to support BIOS, M-System adds a small
SRAM (512 or 1K Bytes) between the NAND Flash and System Bus. The
internal logic of DoC downloads the very first 1 or 2 pages of DoC
to the SRAM on power up. The code in this small area has to init
DRAM and copy other BIOS code from DoC to DRAM to execute. The code
in this small SRAM is called IPL, the other part is thus called SPL.

The stage 1, 2, 3 are rather generic and "older". Due to the primitive
enviroment BIOS have to live, BIOS programmer usually divide their
program into various stages as in the (special) case of DoC. Each
stage does it own specific job and/or load next stage and transfer
execution to the loaded "next stage".

> - What does DOM stand for?  Disk on Media (i.e. hard or floppy disk), in
> contrast to Disk on Chip?
> 


DOM stands for DiskOnModule. This is Flash disk with IDE controller
embedded thus is used exactly the same way as IDE HD.

> - What is the relationship of FreeBIOS to LinuxBIOS?  Has FreeBIOS
> (especially the SourceForge project) been assimilated by LinuxBIOS?
> 

Sort of.

Ollie

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