IRQ-Tables once again

Stefan Reinauer stepan at
Thu Jan 22 14:21:00 CET 2004

* Li-Ta Lo <ollie at> [040122 17:22]:
> > good. things seem to work now. Except that the secondary bus of the 
> > 8151 gets set to 0, where it seems that in our case this should be 2
> > (the AGP device is visible on bus 2) Don't think this matters though
> Did you just dump the IRQ table from normal BIOS and put it in
> LinuxBIOS ?

> That is the same problem we found here. The normal BIOS tries to make
> the secondary bus of 8151 as bus 0. It also tries to hide the bridge
> from IRQ and/or MP table.

My assumption that the secondary bus is 0 on the 8151 comes from reading
the SECONDARY_BUS register while creating the mptable. 

This happens before the irq table is used for the first time.

Some  pirq tables I've looked at showed the complete device tree of 
the machine, including the 2 cpus and all the bridges. We could probably
generate a lot of this information automatically already.
For getting the slots described right we need an additional slot
command/tag in the config mechanism. 
Then we could just walk over all north/southbridges and generate both
an irq table and an mptable from the device tree.


     Stefan Reinauer, SUSE LINUX AG
Teamleader Architecture Development

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