SMP linux

[Gin]

I've been stuck at this problem for a while. My linuxbios boots a
NON-SMP kernel ok but not the SMP one. 
The SMP kernel gets loaded and run. When it tries to access an IDE
drive, an IDE command timed out before anything returns(kernel
messages). My I/O APIC settings correspond to the MP table.

All ISA devices are mapped to the I/O IOAPIC at 0xFEC00000. But where do
we set this I/O APIC up? How does it know to route the IRQs to the local
APIC?

Another question is, does linuxbios setup the local APIC as Virtual Wire
mode that via I/O APIC?

My board is similar to Tyan/s2735, does anyone get this booted with a
SMP linux before??

many thinks,
gin