Help needed to understand code

steven james pyro at linuxlabs.com
Fri Mar 7 07:36:01 CET 2003


Greetings,

Probably the first thing to understand is the overall flow of control.

On powerup, the reset vector at f000:fff0 jumps to the start of the
assembly code. The assembly code consists of a series of modular units
that the config files paste together using include directives. It just
starts at the beginning, and new pieces are tacked on as encountered in
the config files. The config files are invoked by directives like
northbridge and southbridge. The master config file is in the mainboard
directory and is invoked by the user's config file.  Most mainboard
directory have example user configs.

The c code is linked together seperatly and then compressed. The last part
of the asm code decompresses it into RAM and calls hardwaremain
(found in src/arch/<arch>/lib/hardwaremain.c currently, <arch> can be
alpha, i386 or ppc). The remainder of the C code is all invoked from
there.

G'day,
sjames

On Fri, 7 Mar 2003, Shubhangi Jadhav wrote:

> Hi,
> 
> 	I'm a LinuxBIOS newbie. I have downloaded the source code for the same and
> was trying to understand it. Looks too complicated to me.
> 	I'd started with the code for Intel440gx mainboard, but failed to
> understand how the northbridge and southbridge intialization routines are
> invoked.
> 	Can someone tell me how to go about understanding the code?
> 
> Thanks,
> Shubhangi
> 
> 
> 
> _______________________________________________
> Linuxbios mailing list
> Linuxbios at clustermatic.org
> http://www.clustermatic.org/mailman/listinfo/linuxbios
> 

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