Is the pci interrupt number fixed?

[caokai]

Hi,all:
  I have a mpc8245 board with an internel intel 82559er ethernet adapter
.
  I am tring to porting 2.4.17 linux(Montavista Linux 2.1) on this
board. I met a thing that I can't understand.Why my ethernet adapter can
only use a interrupt 18 (assign in arch/ppc/platforms/sandpoint_pci.c)?
Anything else interrupt number can't work on this board.Is it normal?
   Can sombody give me some advice?
regards
caokai


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