See also Documentation/blockdev/paride.txt.
pci=option[,option...] [PCI] various PCI subsystem options:
+ earlydump [X86] dump PCI config space before the kernel
+ changes anything
off [X86] don't probe for the PCI bus
bios [X86-32] force use of PCI BIOS, don't access
the hardware directly. Use this if your machine