Porting Linux (mips) timer interrupts to newer kernel

[Eli]

Hi,
I would like to ask for assistance with Linux (mips cpu) timer
interrupt.
I'm trying to port Linux from 2.6.10 kernel to 2.6.23.
At the 2.6.10, we called to set_except_vector(0, dispatcher).
Any interrupt caught and forwarded by the dispatcher as required
(include the timer interrupts).

Now, on the 2.6.23 I could use a similar routine (plat_irq_dispatch)
to do the same and serve also the timer interrupts.
What disturbs me is the "plat_timer_setup" routine: I could see on
different platforms that this routine is used to
install timer interrupt handler for the timer IRQ.
I assumed that this routine will cause the timer inetrrupt to be
routed directly to the timer handler (instead of calling to
plat_irq_dispatch).
I tried to use it but upon timer IRQ the "plat_irq_dispatch" was
called.
Can you explain about the idea of "plat_irq_dispatch" (which calls to
"setup_irq")?
Can you advice what went wrong?

Thanks in advance,

Eli

[Eli]

Sorry, I meant -
Can you explain about the idea of "plat_timer_setup" (which calls to