[LinuxBIOS] Adding IGEL-316 mainboard
juergen127 at kreuzholzen.de
Mon May 14 10:51:25 CEST 2007
On Monday 14 May 2007 10:07, Luis Correia wrote:
> > Maybe we are able to detect the SPD EEPROM on *some* boards. But never on
> > all boards. There are too many individual incarnations how you can
> > connect the I2C lines to your CPU (thanks to popconserve for the
> > reference schematics!). Mainboard's physical behaviour (I believe) you
> > never can autodetect. So we might need a filestructure you can try to
> > autodetect things, or to hardcode most or all of the required settings.
> > And then call ram_init with this data. Any idea? The faked-SPD alone does
> > not help.
> Just to add up some extra info, on my NOVA4899 board there is an
> hardware monitor chip that has I2C connections to some pins on the
> SO-DIMM socket.
> I've failed to figure out where these lines are connected. The
> reference schematics show the I2C bus being connected to the superIO.
> But on my board they are not connected to either the CS5530 or the
> SuperIO chips. I'm lost here...
> My only hope is to reverse engineer the factory BIOS, which is not a
> task for the fain of heart :)
Boot your mainboard with your factory BIOS and dump the so called BC_*
registers and you are fine (a few registers at offset GX_BASE + 0x8400 up to
GX_BASE + 0x840f. GX_BASE is on most system at 0x40000000). If you do not
change your SDRAM, you can work with these values. Its much easier than to
reverse engineer the BIOS code...
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